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  • Angiosperms  (68)
  • healthy volunteers  (37)
  • hypertension  (28)
  • Springer  (130)
  • 1995-1999
  • 1980-1984  (130)
  • 1950-1954
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  • 1984  (130)
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  • Springer  (130)
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  • 1995-1999
  • 1980-1984  (130)
  • 1950-1954
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  • 1
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 309-313 
    ISSN: 1432-1041
    Schlagwort(e): clonidine ; hypertension ; therapeutic window ; steady state concentration ; pharmacokinetics ; cardiovascular effects
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Clonidine was given orally as monotherapy in increasing daily doses from 3.1 to 25.7 µg/kg to patients with essential hypertension (n=6). When a steady state concentration in plasma was reached at each dose level, the blood pressure (BP) and heart rate were measured during a dosage interval. Effect time — plasma concentration data were submitted to nonlinear regression analysis, which showed that the observed BP effects could be dissociated into depressor and pressor components. A window for the antihypertensive effect was established. At a plasma clonidine concentration of 0.65±0.07 ng/ml 50% of the maximal depressor effect was found, and it was only separated by a factor of 2 from the half maximal pure pressor concentration in plasma. No relationship between the change in heart rate and the plasma clonidine was observed. The findings strengthen the importance of close monitoring of clonidine therapy.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 331-334 
    ISSN: 1432-1041
    Schlagwort(e): metoprolol ; oxprenolol ; hypertension ; beta-blockers ; HDL-cholesterol ; intrinsic sympathomimetic activity ; cardioselectivity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The aim of the present study was to evaluate whether a reduction in HDL-cholesterol is peculiar to non cardioselective beta blockers or whether it is also produced by cardioselective beta1-blockers. 16 patients with primary arterial hypertension on a balanced isocaloric diet were given oxprenolol 120 to 240 mg/day or metoprolol 100 to 200 mg/day in a random cross-over study. No significant change was observed after either treatment in fasting blood glucose, serum total cholesterol and triglycerides. HDL-cholesterol concentration was significantly decreased on metoprolol, from 41 to 36 mg/dl (p〈0.05), while oxprenolol did not affect it at all. The difference might depend on intrinsic sympathomimetic activity which is possessed by oxprenolol and which metoprolol lacks.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 549-553 
    ISSN: 1432-1041
    Schlagwort(e): pafenolol ; hypertension ; antihypertensive therapy ; beta1-blocking agent ; exercise tests ; plasma levels
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Pafenolol, a new selective adrenergic beta1-blocking agent, has been tested for the first time in 6 hypertensive patients. After single oral doses of pafenolol 25 to 100 mg, there was a marked reduction in heart rate and systolic blood pressure during exercise tests. These effects were dose dependent. A significant positive correlation was found between the reduction in heart rate during exercise and the plasma level of pafenolol 5 hours after drug intake (correlation coefficient r=0.94). Side effects were mild and seemed to be dose dependent. It is concluded that this new beta1-blocking agent was effective in reducing blood pressure and was well tolerated.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 627-630 
    ISSN: 1432-1041
    Schlagwort(e): bupropion ; ethanol ; pharmacokinetic interaction ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary A study was performed to determine whether there is a pharmacokinetic interaction between alcohol and the novel antidepressant bupropion. In the first part 8 healthy male volunteers received single doses of 100 mg bupropion hydrochloride orally on 2 occasions accompanied by either ethanol in orange or plain orange drink according to a balanced cross over design. Plasma bupropion concentrations were determined by radioimmunoassay and kinetics analysed with the aid of NONLIN. Blood alcohol levels were assessed by breathalyser. The disposition of bupropion was adequately described by a 2 compartment model and kinetic parameters were not significantly altered by the presence of alcohol. In the second part of the study the same subjects received 40 ml ethanol in orange drink 3.5 h after ingestion of 100 mg bupropion or dummy tablet in a double blind cross over fashion. Bupropion did not affect alcohol kinetics. In contrast to many other psychotropic drugs there is no evidence for a kinetic interaction between bupropion and alcohol.
    Materialart: Digitale Medien
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  • 5
    ISSN: 1432-1041
    Schlagwort(e): etozolin ; ozolinone ; furosemide ; hypertension ; renin ; catecholamines ; chronic renal failure ; steady state kinetics ; plasma levels
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effect on urinary electrolyte excretion, renin release and plasma norepinephrine of single oral doses of 400 mg etozolin (E) and of 40 mg furosemide (F) were studied in hypertensive patients with normal (n=6) and impaired kidney function (n=6). E caused a marked saluresis up to 24 hours, showing its long duration of action. F, however, displayed a brief, brisk peak diuresis, followed by a rebound from the 4th to the 24th hours. The brisk peak diuresis induced by F was associated with pronounced release of renin, almost twice that induced by E. In chronic renal failure the renin release in relation to the magnitude of the diuresis was increased, i.e. the sensitivity of these patients to changes in water homeostasis was increased. E and F stimulated the sympathetic system to roughly the same extent. Patients with essential hypertension had higher plasma levels of norepinephrine than hypertensive patients with chronic renal failure. In addition, hypertensive patients with normal renal function (n=4) and varying degrees of renal impairment (n=11) were also given 400 mg daily for 2 weeks. Effects on blood pressure and electrolyte homeostasis were monitored, as well as the plasma kinetics of metabolite I, ozolinone. At the end of the 2 week treatment E had significantly lowered systolic (−12 mm Hg) and diastolic (−9 mm Hg) blood pressure, and had produced a significant loss of body weight, without altering plasma electrolytes or blood chemistry. There was no accumulation of the effective metabolite ozolinone under conditions of severe impairment of kidney function. It is concluded that E can effectively control high blood pressure in patients with normal and impaired kidney function. Its effective metabolite ozolinone did not accumulate in chronic renal failure.
    Materialart: Digitale Medien
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 397-405 
    ISSN: 1432-1041
    Schlagwort(e): indapamide ; hypertension ; cardiovascular reflexes ; diuretic effect ; blood pressure variability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Nine elderly and 11 young hypertensives underwent continuous ambulatory monitoring of blood pressure (BP), assessment of cardiovascular reflexes and M-mode echocardiography as hospital in-patients prior to treatment with once-daily indapamide (2.5 mg). They were followed as out-patients for 4 months during which time casual BP was measured at monthly intervals. The patients were then readmitted to hospital and studied using the same protocol under similar standardised conditions. The results showed that indapamide reduced casual and ambulatory BP in both young and elderly although the most marked effect was seen on systolic BP. Assessment of cardiovascular reflexes indicates that at least part of the hypotensive action of indapamide is due to a diuretic effect. Treatment with indapamide has comparable results on both young and elderly.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 315-323 
    ISSN: 1432-1041
    Schlagwort(e): captopril ; hypertension ; glomerular filtration ; para-aminohippuric acid ; renal function ; severe drug reaction ; nephrotic syndrome
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effect of captopril up to 450 mg/day on blood pressure and renal function were investigated during sustained treatment of 10 patients whose severe hypertension had not responded to previous therapy. All the patients were kept on diuretics and most of them on β-blockers, too. A control determination of glomerular filtration rate (GFR) and para-aminohippuric acid clearance (CPAH) was performed during the prior treatment. The effect of the addition (or substitution) of captopril were assessed after an average of 25 days (short-term) and 26 weeks (long-term). Short-term treatment produced a 15.5% decrease in mean blood pressure and interindividually variable effects on renal function. On average GFR was somewhat lower and CPAH slightly higher than the control values (not significant). This pattern is quite similar to the effects of most other antihypertensive drugs. On long-term therapy GFR rose by a mean of 9% (NS) and CPAH by 17% (p〈0.02). However, in a patient who developed a captopril-induced nephrotic syndrome, GFR dropped to 56% and CPAH to 50% of the control values. In another patient a transient rise in serum creatinine accompanied a severe drug reaction.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 635-637 
    ISSN: 1432-1041
    Schlagwort(e): theophylline ; inhalation ; saliva-serum distribution ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Six healthy volunteers received an iv infusion of 317 mg lysine theophylline (equivalent to 197 mg anhydrous theophylline) in order to calculate theophylline clearance by standard methods. They subsequently received a 20 minute inhalation of nebulised lysine theophylline. Serum and salivary theophylline concentrations were measured and all saliva was collected for the first hour. From these concentrations estimates were made of the distribution of theophylline into the blood and saliva with 40% to 94% identified in the blood. Very high salivary concentrations were reached during the inhalation phase with saliva: serum concentration ratios of between 60 and 1600.
    Materialart: Digitale Medien
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 115-117 
    ISSN: 1432-1041
    Schlagwort(e): benzodiazepine antagonist ; Ro 15-1788 ; healthy volunteers ; pharmacokinetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The pharmacokinetics of the selective benzodiazepine antagonist Ro 15-1788 has been studied in 6 healthy male volunteers following a single intravenous dose of 2.5 mg. The drug was only slightly bound to plasma proteins (40±8%, mean±SD). A negligible amount (〈0.2% of the dose) of unchanged drug was recovered in urine. Hepatic elimination was rapid, as shown by a short t1/2 of 0.9±0.2 h, and high total plasma and blood clearances of 691±216 ml/min and 716±199 ml/min, respectively. The fast decline of plasma levels from about 60 to 2 ng/ml accounts for the short-lasting reversal of benzodiazepine-induced sedation by Ro 15-1788.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 7-12 
    ISSN: 1432-1041
    Schlagwort(e): nitroglycerin ; plasma concentration ; transdermal administration ; bioavailability ; pharmacodynamics ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary In 6 healthy volunteers, intravenous infusions of nitroglycerin 4.8 and 10.6 µg/min yielded mean steady-state plasma concentrations of 0.5±0.02 and 0.82±0.04 ng/ml as determined by a gas chromatographic/mass spectrometric method. The plasma concentrations reached in the same subjects 17 h after application of Nitroderm TTS 5 and 10 with in vivo release rates of 3.7 and 5.7 µg/min were 0.28±0.01 and 0.37±0.01 ng/ml, respectively. Thus, 75% of the quantity of nitroglycerin released by the systems passed into the circulation. The inter-individual and intra-individual variations in plasma concentrations were similar for both modes of administration. The nitroglycerin-induced morphological changes in the fingerpulse wave were clearly dose-dependent, but it seems that this pharmacodynamic parameter is determined less by the plasma concentration than by the nitroglycerin content of the vascular wall.
    Materialart: Digitale Medien
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  • 11
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 371-373 
    ISSN: 1432-1041
    Schlagwort(e): disodium chromoglycate ; nasal airway resistance ; platelet activating factor ; healthy volunteers ; rhinomanometry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Thirteen healthy subjects participated in a double blind, randomized, cross-over investigation of whether or not intranasal disodium chromoglycate could block the change in nasal airway resistance induced by platelet activating factor (PAF). Placebo or active drug was given for 3 days before intranasal challenge with PAF. Nasal airway resistance before and at intervals after callenge was determined with a rhinomanometer. Pretreatment with disodium chromoglycate blocked the decrease in nasal airway resistance induced by PAF. This indicates an alternative mode of action of disodium chromoglycate in the treatment of allergic airway diseases.
    Materialart: Digitale Medien
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  • 12
    ISSN: 1432-1041
    Schlagwort(e): spironolactone ; canrenone ; metabolites ; pharmacokinetics ; single/multiple oral doses ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The pharmacokinetics of canrenone and ‘total metabolites’ after base hydrolysis was studied in eight young volunteers following single and multiple dose oral administration of spironolactone. The plasma levels of canrenone and ‘total metabolites’ were fitted to a two-compartment open model with a first-order absorption process. From our eight normal subjects studied, the harmonic mean of the distributive half-life (t1/2α) of canrenone was found to be 1.66 h, and the harmonic mean of the terminal elimination half-life (t1/2β) to be 22.6 h. Harmonic means of the distributive and elimination half-lives of ‘total metabolites’ after base hydrolysis were 2.48 h and 28.8 h respectively. The accumulation ratio of canrenone was 2.53, whereas that of ‘total metabolites’ was 1.89. Despite the fact that spironolactone has been shown to induce hepatic metabolism of other drugs, no evidence of autoinduction was noted in the present study, as plasma levels of canrenone and ‘total metabolites’ were found to obey a linear two-compartment model with reproducible absorption and disposition after single and multiple doses.
    Materialart: Digitale Medien
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  • 13
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 447-452 
    ISSN: 1432-1041
    Schlagwort(e): alaproclate ; antipyrine clearance ; serotonin reuptake inhibitor ; healthy volunteers ; antipyrine metabolism ; metabolite clearance ; alaproclate kinetics ; inhibition of drug metabolism
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Alaproclate, a selective serotonin reuptake inhibitor, presently undergoing clinical trial for the treatment of major depressive disorders, has been shown to inhibit hexobarbital metabolism in mice. In the present study the influence of oral alaproclate on the total plasma clearance of antipyrine and on the formation of its metabolites was investigated in 10 healthy volunteers. The peak level of alaproclate was reached after about 1.5 h, and after a distribution phase, its plasma elimination half-life was between 3.0 and 3.5 h. Antipyrine tests were performed before treatment, during the first four doses and after the seventh dose of alaproclate 200 mg/day. During treatment, total plasma antipyrine clearance and the clearance for production of all antipyrine metabolites were reduced by 30%, indicating non-selective inhibition of oxidative drug-metabolizing enzyme activity in man by alaproclate. After the last dose of alaproclate, antipyrine plasma clearance and the clearance to its metabolites returned to control values. In order to allow more detailed evaluation of the results, the time course of the clearances for production of metabolites was investigated. This revealed that the extent of inhibition of metabolite formation by alaproclate was dependent on the plasma alaproclate level, indicating a rapidly reversible inhibition.
    Materialart: Digitale Medien
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  • 14
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 471-475 
    ISSN: 1432-1041
    Schlagwort(e): acyclovir ; A515U ; 6-deoxyacyclovir ; pharmacokinetics ; prodrug ; antiviral chemotherapy ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary A515U (6-deoxyacyclovir) is an analogue of acyclovir devoid of antiviral activity in vitro but which is well absorbed and undergoes conversion to acyclovir after oral administration to rats. The tolerance and pharmacokinetics of various doses of A515U have been studied in 8 healthy volunteers. Single oral doses of 25, 50, 100, 200 and 400 mg A515U and 400 mg acyclovir for comparison were administered to the volunteers at weekly intervals. Concentrations of the parent drug and acyclovir were determined in plasma and urine. The prodrug was well tolerated and did not cause adverse reactions or changes in haematological or biochemical variables. It was well absorbed and conversion to acyclovir was rapid and extensive at all doses. Plasma concentrations of acyclovir achieved with 50 mg A515U orally were comparable to and less variable than those produced by 400 mg acyclovir. A515U was rapidly cleared with a short plasma elimination half life of approximately 0.5 h. The attainment of high plasma concentrations of acyclovir by oral administration of a prodrug may represent an important advance in antiviral chemotherapy.
    Materialart: Digitale Medien
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  • 15
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 505-507 
    ISSN: 1432-1041
    Schlagwort(e): benzodiazepine antagonist ; visual function ; intrinsic effect ; Ro 15-1788 ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Ro 15-1788 is a specific benzodiazepine antagonist, which has also been shown to have some agonist properties. Since benzodiazepine receptors are involved in the physiological mechanisms of vision, a possible intrinsic effect of Ro 15-1788 was sought in 6 healthy volunteers by study of psychophysical flicker thresholds, including critical fusion frequency and low frequency modulation threshold, and pattern reversal visual evoked response, using double blind cross-over methodology. In each session 2 tablets of Ro 15-1788 30 mg were administered. Using a two factorial univariate analysis of variancé, no change was detected in any of the parameters studied.
    Materialart: Digitale Medien
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  • 16
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 535-538 
    ISSN: 1432-1041
    Schlagwort(e): pindolol ; healthy volunteers ; heart rate ; intrinsic sympathomimetic activity ; diurnal heart rate ; nocturnal heart rate ; rebound effect
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effect on heart rate of pindolol 5, 15 and 30 mg/day, a beta-adrenoreceptor blocker possessing intrinsic sympathomimetic activity, administered to 8 healthy volunteers for 14 days was studied. Heart rate was continuously recorded over 24 h during placebo treatment before each sequence, every 2 days during treatment, and then on the 15th, 17th and 18th days. Pindolol in the three doses used had no significant effect on mean heart rate over 24 h. It tended to lower mean diurnal heart rate non-significantly between noon and 6 p.m. Pindolol raised nocturnal heart rate between midnight and 6 a.m. to a comparable extent at all the doses used. Sympathetic tone is at its lowest during that period, which makes it possible to detect the intrinsic sympathomimetic activity of pindolol. After cessation of treatment, a rebound effect was observed, cardioacceleration being most marked after 30 mg/day.
    Materialart: Digitale Medien
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  • 17
    ISSN: 1432-1041
    Schlagwort(e): zetidoline ; prolactin ; aldosterone ; dopamine ; healthy volunteers ; pharmacodynamic effects
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The neuroendocrinological effects of acute oral administration of 20 mg zetidoline, a new antipsychotic drug with antidopaminergic properties, were evaluated in 8 healthy volunteers, by a double-blind, crossover comparison with placebo. Zetidoline significantly increased serum prolactin (p〈0.01 at 1–3 h; p〈0.05 at 4–6 h). No significant change was observed in blood levels of aldosterone, renin, cortisol, growth hormone and electrolytes, or in blood pressure and heart rate. The data suggest that the drug increases prolactin through blockade of dopaminergic receptors. The lack of change in the aldosterone levels may be evidence against the hypothesis of dopaminergic control of aldosterone secretion.
    Materialart: Digitale Medien
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  • 18
    ISSN: 1432-1041
    Schlagwort(e): beta-blocking drugs ; insulin sensitivity ; pancreatic beta-cell function ; hypertension ; propranolol ; atenolol ; insulin secretion ; plasma GIP
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effects of two beta-blocking drugs on endogenous insulin secretion and insulin sensitivity were investigated in a double blind cross-over study in 13 hypertensive patients. The patients were randomly allocated to each of three 2-week treatment periods with propranolol 80 mg b.i.d., atenolol 50 mg b.i.d. and placebo b.i.d. Endogenous insulin secretion was assessed by measuring serum insulin and C-peptide before and 6 min after iv administration of glucagon; insulin sensitivity was determined by measuring insulin binding to erythrocytes, and as the glucose disappearance rate (KITT) after i.v. insulin. Fasting concentrations of serum free fatty acids (S-FFA) and plasma gastric inhibitory polypeptide (P-GIP) were also recorded during the three study periods. Both propranolol and atenolol reduced blood pressure, heart rate and S-FFA concentrations compared to placebo, and all patients showed measurable plasma concentrations of propranolol and atenolol. The results can be considered representative, therefore, of clinical beta-blockade. The two drugs did not significantly influence the fasting blood glucose level. There was an increase in fasting and glucagon-stimulated serum C-peptide concentration during propranolol therapy compared with placebo (p=0.037 and p=0.030, respectively), although this was not reflected by a significant change in serum insulin. Propranolol and atenolol did not significantly influence insulin binding to erythrocytes, but they clearly reduced the glucose disappearance rate KITT was compared to placebo (p=0.0036 and p=0.0003, respectively). The findings support the view that beta-blocking drugs can influence glucose metabolism by mechanisms other than inhibition of endogenous insulin secretion.
    Materialart: Digitale Medien
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  • 19
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 39-42 
    ISSN: 1432-1041
    Schlagwort(e): acetylator phenotype ; hydralazine response ; hypertension ; blood pressure control ; lupus syndrome
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The role of acetylator phenotype in determining the response to hydralazine when it was added to diuretic and β-blocker at doses not exceeding 200 mg daily was examined in 57 hypertensive patients. 81% of rapid acetylators needed 200 mg hydralazine daily compared to 38% of slow acetylators (p〈0.01). Despite higher doses of hydralazine the blood pressure was controlled in only 27% of rapid acetylators compared to 65% of slow acetylators (p〈0.02). The relation of acetylator phenotype to blood pressure response was statistically independent of initial blood pressure, age, sex, body weight and serum creatinine (p〈0.005). Current recommendations on hydralazine dosage are unsatisfactory for the 40% of hypertensive patients who are rapid acetylators. We suggest measurement of the acetylator phenotype in patients who respond incompletely to 200 mg hydralazine daily. About 70% of these patients will be rapid acetylators in whom the dose of hydralazine can be increased safely.
    Materialart: Digitale Medien
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  • 20
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 463-470 
    ISSN: 1432-1041
    Schlagwort(e): dihydroergotamine ; 8′-hydroxy-dihydroergotamine ; plasma metabolites ; bioavailability ; receptor affinity ; healthy volunteers ; liver microsomal incubates
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The plasma concentrations and urinary excretion of dihydroergotamine and its metabolites have been measured after a single oral administration of 3 mg tritium-labelled drug to 6 male volunteers. The plasma level of non-volatile radioactivity declined biphasically with α- and β-phase half-lives of 2.1 h and 32.3 h, respectively. The peak plasma concentration was reached within 3.2h. Urinary excretion of total non-volatile radioactivity was low, amounting to 1.0% of the dose. The parent drug and four metabolites could be quantitated in urine and plasma samples. Metabolite 4 (8′-hydroxy-dihydroergotamine) was isolated from incubates of rat and monkey liver microsomal preparations. In human liver microsomal incubates, metabolite 4 was shown to be the primary metabolite of dihydroergotamine. In receptor binding studies performed with mammalian brain preparations, metabolite 4 had IC50-values at 6 monoaminergic binding sites similar to those of dihydroergotamine. Thus, it appears that the active principle consists at least of dihydroergotamine and its 8′-hydroxy derivative. As the concentration of metabolite 4 exceeded 5–7 times that of dihydroergotamine in urine and plasma, the bioavailability of dihydroergotamine should be reevaluated, taking into account the plasma concentrations of the parent drug and of its acitve metabolite, 8′-hydroxydihydroergotamine.
    Materialart: Digitale Medien
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  • 21
    ISSN: 1432-1041
    Schlagwort(e): Tobanum® ; beta-blocker ; chloranolol ; hypertension ; angina pectoris ; arrhythmia ; detection methods
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The incidence of side-effects on administration of chloranolol (Tobanum®), a beta-adrenergic receptor blocking drug, to 2066 patients with hypertension, angina pectoris or arrhythmias was measured by three different methods. In 600 patients in an efficacy trial (Group 1) both spontaneously reported complaints and objective signs were tabulated. A side effect — directed method, utilising a questionnaire containing a list of possible side-effects was also used, with the questionnaire being completed by the physician. 35 questions referred to anticipated and other side-effects. The trial was performed in two groups: in 537 patients a placebo was also given (Group 2), and in another set of 929 patients (Group 3) the questionnaire inquiry was performed uncontrolled, without placebo. All three groups were comparable in their distribution of sexes, ages and diagnoses, the mean daily dose of chloranolol its use alone or in combination, and in a similar duration of treatment. 55% of all patients received chloranolol therapy for a period of more than 3 months. The ratio of in- and outpatients was 1:5. The side-effect incidence was independent of the age and sex of the patients and of the dose of chloranolol. The incidence was also unaffected whether chloranolol was used alone or in combination. The number of side-effects differed markedly between the three groups, their ratio was 1:10:24 in Groups 1, 2 and 3. Two-thirds of the side-effects subsided spontaneously within 1 month of their onset. The duration of the side-effects varied according to their character: cardiorespiratory side-effects were of the shortest duration and those affecting the central nervous system were the most enduring. The appreciable differences in incidence could be attributed to the methods of collection of the data. It has been stated that placebo controlled trials using a detailed questionnaire are the most suitable for estimating the incidence of side-effects; recording side-effects spontaneously reported by patients are insufficiently sensitive, and uncontrolled trials using a questionnaire have been shown to be too sensitive. The revealed incidence of side effects leading to interruption of treatment is less affected by the method chosen. In 100 patients (4.8%) therapy had to be suspended because of the side-effects of chloranolol (Group 1: 1%, Group 2: 6.20%, Group 3: 6.6%). Comparison of the incidence of cessation of therapy due to side-effects did not show an appreciable difference between the various beta-adrenergic receptor blocking agents, including chloranolol.
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  • 22
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 191-196 
    ISSN: 1432-1041
    Schlagwort(e): pizotifen 5-hydroxyindoleacetic acid ; homovanillic acid ; urinary excretion ; healthy volunteers ; migraine prevention
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary A single dose of 0.5 mg pizotifen or a placebo was administered to 10 healthy male volunteers in a double blind cross-over trial. 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) in hourly urine samples were determined by liquid chromatography with amperometric detection. The 5-HIAA levels were strongly correlated with the HVA levels in control samples (r=0.95, p〈0.001). Pizotifen produced a significant increase in the urinary 5-HIAA/HVA ratio over the 3 hours following absorption of the drug (+0.21, +0.18, +0.19, p〈0.05). The increase demonstrates an interaction between pizotifen and 5-HT metabolism, which may be involved in its antimigraine effect.
    Materialart: Digitale Medien
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  • 23
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 483-489 
    ISSN: 1432-1041
    Schlagwort(e): radiosensitiser ; pharmacokinetics ; healthy volunteers ; tumour patients ; Ro 03-8799
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary A new hypoxic cell radiosensitiser, Ro 03-8799 has been administered intravenously to human volunteers and its kinetic parameters derived from plasma and urine data. Good penetration of drug into tumour tissue is found, consistent with its large volume of distribution. The plasma clearance of this compound is rapid due to high metabolic and renal clearances. These parameters combine to produce an elimination half-life of 5.6 h, approximately half that of misonidazole, a well studied radiosensitiser. It is hoped that this decrease in total body exposure will also reduce the cumulative toxicity seen when misonidazole is administered repeatedly.
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  • 24
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 501-503 
    ISSN: 1432-1041
    Schlagwort(e): valpromide ; valproic acid ; pharmacokinetics ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The pharmacokinetics of valpromide, a primary amide of valproic acid, was investigated in 6 healthy, adult male volunteers, each of whom was given 900 mg as a marketed, enteric-coated tablet and a solution. Valpromide was biotransformed to valproic acid after the administration of the tablet and the solution with a bioavailability of 0.79±0.24 and 0.77±0.12, respectively, relative to a marketed tablet of valproic acid. The absorption of valpromide was not rate-limited by dissolution. As a solid, non-hygroscopic, neutral prodrug of valproic acid, valpromide may be a good alternative to valproic acid and sodium valproate.
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  • 25
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 1-6 
    ISSN: 1432-1041
    Schlagwort(e): hypertension ; beta-blockers ; propranolol ; metoprolol ; labetalol ; exercise ; heart rate ; blood pressure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary In a double blind, within patient investigation of twenty-four patients (nineteen males and five females) with a mean age of 46.3 years (SD 10.9 years) with mild to moderate essential hypertension a comparison between equipotent beta-blocking doses of propranolol, metoprolol and labetalol was carried out. Blood pressure and pulse rate were measured in lying, sitting and standing positions and before, during and after isometric and dynamic exercise. Peak expiratory flow was recorded before and during dynamic exercise. All the active treatments were better than placebo in reducing blood pressure and heart rate. Comparing the effects of treatment, labetalol lowered sitting diastolic pressure significantly more than propranolol and standing diastolic pressure than both propranolol and metoprolol. Metoprolol and propranolol were more effective in reducing heart rate. Propranolol significantly reduced peak flow rate compared to labetalol. During the exercise, both isometric and dynamic, the heart rate and the blood pressure, both systolic and diastolic, of the treated patients were lower than those on placebo. There was little difference between the drugs in the influence on blood pressure, but metoprolol and propranolol were significantly more effective than labetalol in lowering the heart rate.
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  • 26
    ISSN: 1432-1041
    Schlagwort(e): alpha-methyldopa ; propranolol ; hypertension ; side effects ; blood pressure control
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary A multicentre study of 6–10 weeks duration was performed in 60 ambulant hypertensive patients aged over 60 years to compare the efficacy of methyldopa and propranolol with particular reference to the occurrence of cold extremities and sleep disturbances. Blood pressure was effectively controlled by both drugs being reduced from a mean of 180/108 mmHg to 161/93 with methyldopa and 180/108 to 162/94 with propranolol. More patients treated with methyldopa (74%) achieved the target diastolic blood pressure of 95 mmHg or below compared with those treated with propranolol (58%). Side effects were more frequent in the propranolol group necessitating the withdrawal of four patients from the study. Only one patient on methyldopa was withdrawn. The incidence of cold extremities was significantly greater with propranolol. The occurrence of sleep disturbances was similar in both groups. In this group of elderly patients methyldopa was better tolerated than propranolol.
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  • 27
    ISSN: 1432-1041
    Schlagwort(e): trimethoprim ; concentration ; urinary excretion ; healthy volunteers ; steady state ; pharmacokinetics ; serum creatinine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The steady state pharmacokinetics of trimethoprim was determined after 300 mg orally once daily to 6 healty volunteers for 9 days. The microbiological assay of plasma level was unreliable at trimethoprim concentrations 〉4 µg/ml, so results from an HPLC-assay are given. Steady state was present after 3 days. The plasma concentration peaked 1 to 4 h (mean 2.0 h) after the dose at a mean of 6.0 µg/ml (range 3.1–9.5 µg/ml); the minimum value was 1.5 µg/ml (range 0.6–2.9 µg/ml). The mean AUCss was 77 µg/ml · h and the mean plasma clearancess was 67 and 74 ml/min on Days 8 and 9. Renal clearance was about 60% of the plasma clearance. The average plasma half life was 10.6 h (range 8.7–15.3 h). Thus, there was considerable interindividual variation in all pharmacokinetic parameters. 72 h after the last dose trimethoprim was detectable in plasma in only 1 of the 6 subjects. The minimum urinary concentration of trimethoprim during treatment was always well above (range 22 to 220 µg/ml) the MIC values for most urinary tract pathogens. Therefore, a daily dose of 300 mg trimethoprim results in a therapeutic concentration in urine at steady state that lasts throughout the dosing interval and in most subjects probably lasts also for a further 24 h. Trimethoprim administration raised mean serum creatinine from 67 to 97 µmol/l, probably due to competitive inhibition of the tubular secretion of creatinine.
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  • 28
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 543-547 
    ISSN: 1432-1041
    Schlagwort(e): indapamide ; hypertension ; glomerular filtration ; arginine vasopressin ; free water clearance ; blood pressure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Renal plasma flow (RPF), glomerular filtration rate (GFR), arginine vasopressin in plasma (AVP), free water clearance ( $${\text{C}}_{{\text{H}}_{\text{2}} {\text{O}}}$$ ) and blood pressure (BP) were determined in 11 patients with essential hypertension at the end of 3 consecutive periods of observation each of 6 of weeks duration; indapamide 2.5 mg daily was given in period 2 and placebo in periods 1 and 3. RPF and GFR were reduced by 9% and BP by 9%/14% supine and 14%/12% standing during indapamide treatment. Changes in renal haemodynamics were not correlated with those in BP. AVP was not significantly altered by indapamide and was not correlated with BP. Indapamide reduced $${\text{C}}_{{\text{H}}_{\text{2}} {\text{O}}}$$ possibly due to the reduction in GFR. It is concluded that indapamide evidently induces redistribution of the cardiac output, with enhanced muscle blood flow and reduced renal perfussion, and that AVP does not seem to be involved in blood pressure regulation in mild to moderate essential hypertension under basal conditions.
    Materialart: Digitale Medien
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  • 29
    ISSN: 1432-1041
    Schlagwort(e): beta-blockers ; hypertension ; ISA ; CS ; cold extremities
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Patients with essential hypertension were interviewed prior to entering therapeutic studies in general practice. Patients' age, sex and details of antihypertensive therapy (if any) were noted, as were their spontaneously reported symptoms. Complaints of cold extremities were highest in those taking a beta-blocker (4.1%). Those untreated or taking other therapies complained less often. Those patients taking a beta-blocker with ISA complained less often (3.1%) of cold extremities than those taking a beta-blocker without ISA (5.2%).
    Materialart: Digitale Medien
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  • 30
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 67-74 
    ISSN: 1432-1041
    Schlagwort(e): acetylsalicylic acid ; platelet function ; salicylate ; controlled release formulation ; single dosing ; continuous dosing ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The extent to which a controlled release acetylsalicylic acid (ASA) formulation inhibited platelet function has been evaluated in single and chronic dosing studies. In the single dose study, the platelet inhibitory effect of the controlled release formulation was compared with that of an equivalent dose of soluble ASA and an equimolar dose of sodium salicylate (SA). In the chronic dosing study, ASA dose-response curves for platelet function, including cyclooxygenase activity, were determined for various doses (20–1300 mg) of the controlled release (enteric coated pellets) ASA formulation taken by volunteers daily for one week. Platelet function was assessed by the degree of inhibition of aggregation for several aggregating agents, and the degree of inhibition of activity of platelet cyclooxygenase quantified by the estimation of malondialdehyde (MDA) production. Plasma ASA and SA concentrations were also determined in each study. The controlled release product inhibited platelet function to the same extent as an equimolar dose of soluble ASA, but did so with much lower and sometimes undetectable peak systemic plasma ASA concentrations. SA, the direct metabolite of aspirin, did not have any effect on platelet function. The ASA dose-platelet function response curves obtained from chronic dosing with the controlled release formulation appeared to be similar to those reported previously for the soluble product. The inhibition of platelet function appeared to be unrelated to plasma ASA concentrations.
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  • 31
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 13-17 
    ISSN: 1432-1041
    Schlagwort(e): nifedipine ; hypertension ; blood pressure decrease ; drug combination
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The medication of patients receiving hydralazine, captopril and minoxidil was replaced by a new galenical form, long-acting nifedipine. An additional decrease in blood pressure was observed in most of the patients. Renal function was maintained in all of them. Adverse reactions may be reduced by the use of long-acting nifedipine, which would permit a reduction in the dosage of captopril and minoxidil.
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  • 32
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 23-27 
    ISSN: 1432-1041
    Schlagwort(e): hypertension ; alpha2-adrenoceptors ; blood pressure ; clonidine ; guanfacine ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The time courses of the changes in plasma growth hormone and noradrenaline concentrations in response to 15 min infusions of clonidine 0.2 mgs and guanfacine 2 mgs, were studied in six normal volunteers, in a double-blind, randomised, crossover study. Plasma noradrenaline fell within 15 min of the commencement of drug administration, by 36±14% after clonidine (p〈0.05) and by 32±11% (p〈0.05) after guanfacine. Plasma growth hormone was not significantly elevated until the 30th minute to 12.0±4.7 lU/ml (p〈0.05) after clonidine and 14.7±11.5 lU/ml (p〈0.05) after guanfacine, having been undetectable prior to both drugs. The reduction in plasma noradrenaline by these α2-adrenergic agonists, prior to activation of central adrenoceptors as detected by changes in plasma growth hormone, is evidence for a peripheral component in their sympatholytic effect.
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  • 33
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 75-80 
    ISSN: 1432-1041
    Schlagwort(e): bupropion ; alcohol interaction ; healthy volunteers ; performance ; autonomic functions
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effects of bupropion and ethanol were examined alone and in combination in a placebo controlled, double-blind, crossover study in 12 healthy volunteers. Results were subjected to analysis of variance and differences ofp〈0.05 taken as significant. In the main study using the Wilkinson auditory vigilance test, no active treatment or combination of treatments produced significant change compared with placebo. However, when compared with bupropion 100 mg, vigilance was significantly impaired by 32 ml alcohol alone though not when combined with bupropion. No significant changes in reaction time or short term memory occurred. Visual analogue scales indicated that the subjects were mentally slower after alcohol 32 ml than after placebo. Combination of bupropion 100 mg with alcohol 32 ml abolished this difference. A similar pattern occurred with group ratings indicating mental sedation. Subjects were clearly able to differentiate between the 16 ml and 32 ml doses of alcohol when assessing their degree of inebriation. Combination of bupropion with alcohol made no difference to the ratings of inebriation. The top dose of alcohol tended to increase energy in the low frequency EEG bands. Combination of the top alcohol dose with bupropion, however, produced a significant reversal with lowered energy in the 4–7.5 Hz band. Combination of bupropion with alcohol failed to change the blood alcohol concentration achieved.
    Materialart: Digitale Medien
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  • 34
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 119-121 
    ISSN: 1432-1041
    Schlagwort(e): S-adenosyl-L-methionine ; pharmacokinetics ; protein binding ; dose-dependent kinetics ; healthy volunteers ; urinary excretion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary S-Adenosyl-L-methionine (AdoMet) kinetics was studied in 6 male subjects given 100 and 500 mg i. v. Drug concentrations in plasma and urine were assayed using a radioenzymatic method. Pharmacokinetic parameters were estimated according to an open two-compartment model. The apparent volumes of distribution after the 100 and 500 mg doses were 407±27 and 443±36 ml/kg (mean±SEM), terminal half-lives 81±8 and 101±7 min and body clearances 3.7±0.5 and 3.1±0.2 ml/min per kg. Urinary excretion was 34±3 and 40±2% of the administered dose. The results demonstrate that drug disposition occurs more via metabolism than via renal excretion, and it is not dependent on the administered dose. Binding of AdoMet to serum proteins is negligible.
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  • 35
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 7-12 
    ISSN: 1432-1041
    Schlagwort(e): nitroglycerin ; plasma concentration ; transdermal administration ; bioavailability ; pharmacodynamics ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary In 6 healthy volunteers, intravenous infusions of nitroglycerin 4.8 and 10.6 µg/min yielded mean steady-state plasma concentrations of 0.5±0.02 and 0.82±0.04 ng/ml as determined by a gas chromatographic/mass spectrometric method. The plasma concentrations reached in the same subjects 17 h after application of Nitroderm TTS 5 and 10 with in vivo release rates of 3.7 and 5.7 µg/min were 0.28±0.01 and 0.37±0.01 ng/ml, respectively. Thus, 75% of the quantity of nitroglycerin released by the systems passed into the circulation. The inter-individual and intra-individual variations in plasma concentrations were similar for both modes of administration. The nitroglycerin-induced morphological changes in the fingerpulse wave were clearly dose-dependent, but it seems that this pharmacodynamic parameter is determined less by the plasma concentration than by the nitroglycerin content of the vascular wall.
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  • 36
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 147-152 
    ISSN: 1432-1041
    Schlagwort(e): moxonidine ; clonidine ; hypertension ; double-blind crossover ; side-effects ; withdrawal
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The antihypertensive effect of moxonidine·HCl·H2O (MOX) was compared with that of clonidine·HCl (CLON) in a randomized double-blind crossover study in 20 hypertensive outpatients (BP range 154–178/96–108 mmHg). After 2 weeks without antihypertensive medication, either MOX 0.2 mg daily or CLON 0.2 mg daily was given and the dose was titrated until the diastolic blood pressure fell below 90 mmHg. The first treatment period was continued for 2 weeks and, after crossover without a wash-out period, it was followed by the second treatment for a further 2 weeks. Within the first 4 days of administration 0.2–0.4 mg of either agent caused a significant decrease in BP (p〈0.001) from a mean of 166/100 mmHg to 149/86 mmHg after CLON (approx. −10/−14%), and 163/99 mmHg to 146/84 mmHg after MOX (approx. −10/−15%). No significant difference in the fall in BP or pulse rate was detected between the two drugs. In the mean daily dose of 0.3 mg both drugs showed the same antihypertensive activity, but on CLON a higher incidence of side effects (p=0.003) was noted, and after discontinuation of therapy a more rapid rise in BP (systolic BP p〈0.01, diastolic BP p〈0.02) was found. 17 patients on CLON complained of side effects, especially tiredness and dry mouth, whilst only 6 patients on MOX were affected (p=0.003).
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  • 37
    ISSN: 1432-1041
    Schlagwort(e): guanfacine ; hydrallazine ; hypertension ; sympathetic nervous activity ; plasma renin activity ; cardiac and systemic haemodynamics ; blood pressure ; limb blood flow ; limb vascular resistance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effect of guanfacine and hydrallazine on cardiovascular haemodynamics and on sympathetic nervous activity has been studied in 16 patients with essential hypertension. Two groups of patients were investigated: in Group A guanfacine brought the blood pressure back to normal (diastolic blood pressure ⩽90 mmHg), and in Group B diastolic blood pressure was 〉 90 mmHg and required the addition of hydrallazine. Guanfacine significantly decreased heart rate, plasma renin activity and urinary excretion of noradrenaline, without altering cardiac contractility. In Group B, guanfacine 2 to 6 mg/day produced a significant decrease in blood pressure from 178.7/112.4 to 164.4/102.9 mmHg and in heart rate from 77.1 to 62.7 beats/min after 4 weeks of treatment. Guanfacine did not significantly alter preejection period, cardiac output or total peripheral resistance. Hydrallazine 50 to 300 mg/day caused a further reduction in blood pressure from 164.4/102.9 to 150.7/90.2 mmHg and an increase in heart rate from 62.7 to 72.1 beats/min. Limb blood flow was increased from 4.55 to 5.93 ml/100 g/min and limb vascular resistance was decreased from 39.55 to 23.6 mmHg 100 g·min/ml. Hydrallazine also caused a slight increase in plasma renin activity and urinary excretion of noradrenaline. It is concluded that guanfacine is a useful agent to block a hydrallazine-induced increase in sympathetic nervous activity.
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  • 38
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 407-414 
    ISSN: 1432-1041
    Schlagwort(e): piretanide ; hypertension ; triamterene ; double blind comparison ; potassium ; magnesium ; side-effects ; serum electrolytes ; serum parameters
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary In a randomized, double blind, parallel group study in out patients with mild to moderate essential hypertension the effects of piretanide on serum electrolytes and on blood pressure were compared with those of triamterene alone and the combination piretanide + triamterene. 136 patients entered the study; 18 patients did not fulfill the inclusion criteria (RRdiast was below 95 mmHg or above 120 mmHg) at the end of the placebo period, 6 dropped out due to side effects, and 1 due to lack of efficacy. Data from 1 patient were not evaluated because the patient did not come regularly for checkups. The results for 110 patients were analyzed. Piretanide 6 mg b.d. and piretanide 6 mg + triamterene 50 mg b.d. produced a significant reduction both in supine and erect blood pressure, which was evident at 2 weeks and which increased over the ensuing 12 week trial period. A mean maximal fall of 16.5% was noted in the piretanide group and 15% in the piretanide + triamterene group. Triamterene alone (50 mg b.d.) also reduced diastolic and systolic blood pressures but the reduction was significantly less (diastolic blood pressure) than in both the piretanide groups, and it showed a more rapid return to pretreatment level during a placebo washout phase at the end of the study. A reduction in standing diastolic blood pressure below 95 mmHg was attained in 84% of patients in the piretanide group, 82% in the piretanide + triamterene group and in only 58% of the triamterene group. There were no significant changes within groups nor differences between the three groups in serum potassium or magnesium. 7 patients were withdrawn from the study because of side-effects due to too marked a clinical action (polyuria, orthostatic disorders and hypotension), one from the piretanide group, and the others in the piretanide + triamterene group. One patient in the triamterene group left the study prematurely due to the lack of effect.
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  • 39
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 453-458 
    ISSN: 1432-1041
    Schlagwort(e): dipyrone ; metabolism ; metabolite pharmacokinetics ; acetylation polymorphism ; healthy volunteers ; dapsone phenotyping
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The pharmacokinetics of the dipyrone metabolites 4-methylaminoantipyrine (MAA), 4-aminoantipyrine (AA), 4-formylaminoantipyrine (FAA) and 4-acetylaminoantipyrine (AAA) were evaluated following the administration of a single oral 1.0 g dose of dipyrone to 23 healthy volunteers. Twelve were slow and 11 were rapid acetylators as previously determined by dapsone phenotyping. For MAA and FAA the mean peak plasma concentrations were 10.5±2.8 µg/ml and 2.1±0.8 µg/ml and the half-lives were 3.3±1.0 and 10.1±1.8 h, respectively. No significant difference was found between rapid and slow acetylators in MAA and FAA kinetics. For AA, the mean peak plasma concentrations were 2.7±0.6 and 1.6±0.7 µg/ml (p〈0.01), the peak times 6.7±2.1 and 3.1±1.1 h (p〈0.01) and the half-lives were 5.5±1.0 and 3.8±1.2 h in slow and rapid acetylators, respectively. For AAA, the mean peak plasma concentrations were 1.6±0.4 and 4.4±1.1 µg/ml (p〈0.01) and the peak time 16.1±5.1 and 10.0±2.6 h (p〈0.01) in slow and rapid acetylators, respectively. There was no difference in the elimination half-life between the two groups (10.6±2.2 h). Thus, it has been demonstrated that the AAA/AA ratio is an indicator of the acetylation phenotype, as it is closely correlated with that determined by dapsone (r=0.895, p〈0.0005).
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  • 40
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 495-497 
    ISSN: 1432-1041
    Schlagwort(e): ranitidine ; aldosterone secretion ; sodium depletion ; drug interference ; plasma renin activity ; biochemical parameters ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effect of a 3-day oral course of ranitidine on plasma aldosterone level has been studied in 6 normotensive volunteers maintained in a state of sodium depletion. A significant fall in plasma aldosterone (p〈0.05–0.02), in both the overnight recumbency levels and in the levels obtained during a two hour period of ambulation was observed. The change took place in the absence of variation in plasma renin activity and potassium. Plasma cortisol and prolactin levels were lower after ranitidine at the beginning of the test but their values were not significantly different after ambulation during ranitidine therapy. Ranitidine appears to interfere with aldosterone secretion in vivo.
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  • 41
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 529-534 
    ISSN: 1432-1041
    Schlagwort(e): beta-adrenoceptor blocking agents ; hypertension ; adverse reactions ; atenolol ; bopindolol ; pindolol
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The efficacy of once-daily bopindolol, a nonselectiveβ-adrenoceptor blocking agent with partial agonist activity, and of pindolol and atenolol in the treatment of essential hypertension has been compared. 369 patients were investigated in a double-blind parallel-group study. The treatment period was 10 weeks. Blood pressure normalisation (diastolic BP equal to or less than 90 mmHg) was to be achieved by a stepwise increase in the dose of the test drugs, and, if required, by addition of a diuretic. Normalisation of blood pressure was achieved in 71 to 76% of the subjects, with no significant differences between bopindolol, pindolol, and atenolol. Special attention was given to evaluation of side effects by using two methods for registration of all adverse events during the study. A low incidence of drug-induced side effects was observed, with no significant difference between bopindolol, pindolol, and atenolol. There was no evidence of unsuspected adverse reactions due to bopindolol.
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  • 42
    ISSN: 1432-1041
    Schlagwort(e): cimotaxone ; MAO inhibitor ; plasma prolactin ; circadian rhythm ; healthy volunteers ; hypothalamic MAO ; prolactin secretion ; metabolism ; pharmacokinetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Prolactin (PRL) secretion is stimulated by serotonin (5-HT) and inhibited by dopamine (DA). 5-HT is generally recognized as a substrate for type A monoamine oxidase (MAO), whereas DA is considered as a substrate for either A or B, or both forms of MAO, depending on the species and tissues used. The effect of cimoxatone, a reversible, selective MAO-A inhibitor, on diurnal variation in plasma PRL level was investigated in healthy adults after a single 40 mg oral dose, as an indirect approach to investigating whether DA is preferentially a substrate for Type A or B MAO in man. The circadian rhythm in PRL, stress conditions and diet were taken into account in the present study, which was placebo-controlled. There was a slight but significant reduction in circulating PRL in the six subjects, which persisted for at least 9 h after cimoxatone. However, the duration of the decrease in plasma PRL was shorter than the inhibition of MAO-A. The results are not inconsistent with the presence of both forms of MAO in the human hypothalamus and with DA as a substrate for both forms in this region, if it is assumed that the hypothalamic concentrations of the drug during the period 0–9 hours was sufficiently high to inhibit DA deamination by both forms of MAO.
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  • 43
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 129-131 
    ISSN: 1432-1041
    Schlagwort(e): aprindine ; antiarrhythmic agent ; healthy volunteers ; plasma level ; oral administration ; pharmacokinetics ; urinary excretion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The disposition of aprindine following a single oral dose can best be described by a two-compartment open model. The mean plasma half-life (t1/2β) increased from 8.0±2.1 h (SD) after a 25 mg dose to 9.4±2.9 h after 50 mg and to 15.8±2.6 h after 100 mg, with a decrease in total plasma clearance (Cl/F) and volume of distribution at steady state (Vdss/F) and during β-phase (Vdβ/F). The area under plasma concentration-time curve (AUC), maximum plasma concentration (Cmax) and the amount of unchanged aprindine excreted in the urine increased in a non-linear fashion with the increase in dose. The t1/2β after multiple oral doses showed a 3-fold increase over the single dose value. These results indicate that aprindine shows dose-dependent non-linear kinetics.
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  • 44
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 157-162 
    ISSN: 1432-1041
    Schlagwort(e): hypertension ; hydrochlorothiazide ; atenolol ; side effects ; therapeutic efficacy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary After screening a local population in the northern part of The Netherlands for hypertension, 119 patients with a diastolic pressure (DP) between 95 and 120 mmHg were randomised and treated either with 50 mg hydrochlorothiazide (n=59) or 100 mg atenolol (n=60). After 1 month of treatment 6 patients in the hydrochlorothiazide group and 24 patients in the atenolol group had reached a DP⩽90 mmHg (p〈0.001). 43 of the 50 non-responders to hydrochlorothiazide were switched to atenolol and 30 of the 35 non-responders to atenolol were changed to hydrochlorothiazide. One month after the switch 19 patients in the atenolol group and 2 patients in the hydrochlorothiazide group had reached a DP⩽90 mmHg (p〈0.001). After 6 months of treatment 32 of the 43 atenolol responders and 7 of the 8 hydrochlorothiazide responders were still receiving the same medication, as their DP was still⩽90 mmHg. Non-responders to either medication were given the combination (n=46). 21 patients now became normotensive as did a further 10 after increasing the dose of atenolol to 200 mg. Thus, in all 70 patients had a blood pressure ⩽90 mmHg after treatment for 4 months. Both drugs induced a significant reduction in the total of number of complaints after 1 month of treatment. They did not differ from each other. The reduction was seen both in responders and non-responders and persisted during treatment for 6 months. It is concluded that in terms of short-term efficacy the cardioselective, hydrophilic beta adrenoceptor-blocking drug atenolol is preferable to hydrochlorothiazide in the treatment of uncomplicated hypertension.
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  • 45
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 603-608 
    ISSN: 1432-1041
    Schlagwort(e): pinacidil ; hypertension ; pinacidil pyridine-N-oxide ; urinary excretion ; protein binding ; pharmacokinetics ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Preliminary investigation in 3 healthy volunteers suggested that intravenous pinacidil in a dose of 0.2 mg/kg had a potent but well-tolerated hypotensive action in the supine position. Facial flushing, uncomfortable chest sensation and distressing postural hypotension occurred at serum concentrations above 300 ng/ml. Pinacidil, 0.2 mg/kg, was given intravenously over 4 min to 15 healthy volunteers in the supine position. Maximum fall in mean arterial pressure (MAP) was 15.7±6.0 mmHg. Maximum rise in heart rate was 23.8±6.6 beats/min. Pinacidil serum distribution half-life ( $${\text{T}}_{{\raise0.7ex\hbox{${\text{1}}$} \!\mathord{\left/ {\vphantom {{\text{1}} {{\text{2}}\alpha }}}\right.\kern-\nulldelimiterspace}\!\lower0.7ex\hbox{${{\text{2}}\alpha }$}}}$$ ) was 13.4±8.5 min and elimination half-life ( $${\text{T}}_{{\raise0.7ex\hbox{${\text{1}}$} \!\mathord{\left/ {\vphantom {{\text{1}} {{\text{2}}\beta }}}\right.\kern-\nulldelimiterspace}\!\lower0.7ex\hbox{${{\text{2}}\beta }$}}}$$ ) was 2.13±0.49 h. The apparent volume of distribution (Vdβ) was 90.3±13.21 and total body clearance was 31.1±9.61/h. Pinacidil was approximately 40% bound to plasma protein over the concentration range 40–400 ng/ml. Urinary excretion of unchanged pinacidil accounted for 5.7 ± 1.3% of the administered dose over 24 hours and urinary excretion of the major metabolite, pinacidil pyridine-N-oxide, was 31.6±9.2% of the administered dose. It was concluded that intravenous pinacidil is a potent vasodilator hypotensive compound, with a duration of action between 1.5 and 2 h.
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  • 46
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 661-661 
    ISSN: 1432-1041
    Schlagwort(e): endralazine ; hypertension ; elimination half-liefe ; compartment model
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Materialart: Digitale Medien
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  • 47
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 26 (1984), S. 761-767 
    ISSN: 1432-1041
    Schlagwort(e): drug absorption ; intoxication ; activated charcoal ; disopyramide ; indomethacin ; trimethoprim ; healthy volunteers ; adsorption capacity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The efficacy of various charcoal-to-drug ratios for the absorption of drugs was studied in 6 healthy volunteers and in vitro at two pHs. Disopyramide 200 mg, indomethacin 50 mg and trimethoprim 200 mg were ingested on an empty stomach with 100 ml water. After 5 min the subjects ingested a charcoal suspension in 300 ml — 2.5 g, 10 g, 25 g or 50 g of Norit A, or 10 g of PX-21, or water 300 ml only. Increasing the dose of activated charcoal from 2.5 g to 50 g reduced the gastrointestinal absorption of disopyramide and indomethacin from 30–40% to 3–5%, and that of trimethoprim from 10% to 1% of the respective controls. Disopyramide and trimethoprim were best adsorbed by charcoal in vitro at neutral and indomethacin at acid pH, but saturation of the adsorption capacity was apparent at charcoal-to-drug ratios less than 7.5. Combining the in vitro and in vivo results it can be concluded that the dose of activated charcoal to be given in acute intoxication should be as large as possible, because the drug history is often unknown.
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  • 48
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 75-80 
    ISSN: 1432-1041
    Schlagwort(e): bupropion ; alcohol interaction ; healthy volunteers ; performance ; autonomic functions
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effects of bupropion and ethanol were examined alone and in combination in a placebo controlled, double-blind, crossover study in 12 healthy volunteers. Results were subjected to analysis of variance and differences ofp〈0.05 taken as significant. In the main study using the Wilkinson auditory vigilance test, no active treatment or combination of treatments produced significant change compared with placebo. However, when compared with bupropion 100 mg, vigilance was significantly impaired by 32 ml alcohol alone though not when combined with bupropion. No significant changes in reaction time or short term memory occurred. Visual analogue scales indicated that the subjects were mentally slower after alcohol 32 ml than after placebo. Combination of bupropion 100 mg with alcohol 32 ml abolished this difference. A similar pattern occurred with group ratings indicating mental sedation. Subjects were clearly able to differentiate between the 16 ml and 32 ml doses of alcohol when assessing their degree of inebriation. Combination of bupropion with alcohol made no difference to the ratings of inebriation. The top dose of alcohol tended to increase energy in the low frequency EEG bands. Combination of the top alcohol dose with bupropion, however, produced a significant reversal with lowered energy in the 4–7.5 Hz band. Combination of bupropion with alcohol failed to change the blood alcohol concentration achieved.
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  • 49
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 13-17 
    ISSN: 1432-1041
    Schlagwort(e): nifedipine ; hypertension ; blood pressure decrease ; drug combination
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The medication of patients receiving hydralazine, captopril and minoxidil was replaced by a new galenical form, long-acting nifedipine. An additional decrease in blood pressure was observed in most of the patients. Renal function was maintained in all of them. Adverse reactions may be reduced by the use of long-acting nifedipine, which would permit a reduction in the dosage of captopril and minoxidil.
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  • 50
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 23-27 
    ISSN: 1432-1041
    Schlagwort(e): hypertension ; alpha2-adrenoceptors ; blood pressure ; clonidine ; guanfacine ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The time courses of the changes in plasma growth hormone and noradrenaline concentrations in response to 15 min infusions of clonidine 0.2 mgs and guanfacine 2 mgs, were studied in six normal volunteers, in a double-blind, randomised, crossover study. Plasma noradrenaline fell within 15 min of the commencement of drug administration, by 36±14% after clonidine (p〈0.05) and by 32±11% (p〈0.05) after guanfacine. Plasma growth hormone was not significantly elevated until the 30th minute to 12.0±4.7 lU/ml (p〈0.05) after clonidine and 14.7±11.5 lU/ml (p〈0.05) after guanfacine, having been undetectable prior to both drugs. The reduction in plasma noradrenaline by these α2-adrenergic agonists, prior to activation of central adrenoceptors as detected by changes in plasma growth hormone, is evidence for a peripheral component in their sympatholytic effect.
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  • 51
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 119-121 
    ISSN: 1432-1041
    Schlagwort(e): S-adenosyl-L-methionine ; pharmacokinetics ; protein binding ; dose-dependent kinetics ; healthy volunteers ; urinary excretion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary S-Adenosyl-L-methionine (AdoMet) kinetics was studied in 6 male subjects given 100 and 500 mg i. v. Drug concentrations in plasma and urine were assayed using a radioenzymatic method. Pharmacokinetic parameters were estimated according to an open two-compartment model. The apparent volumes of distribution after the 100 and 500 mg doses were 407±27 and 443±36 ml/kg (mean±SEM), terminal half-lives 81±8 and 101±7 min and body clearances 3.7±0.5 and 3.1±0.2 ml/min per kg. Urinary excretion was 34±3 and 40±2% of the administered dose. The results demonstrate that drug disposition occurs more via metabolism than via renal excretion, and it is not dependent on the administered dose. Binding of AdoMet to serum proteins is negligible.
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  • 52
    ISSN: 1432-1041
    Schlagwort(e): beta-blockers ; hypertension ; ISA ; CS ; cold extremities
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Patients with essential hypertension were interviewed prior to entering therapeutic studies in general practice. Patients’ age, sex and details of antihypertensive therapy (if any) were noted, as were their spontaneously reported symptoms. Complaints of cold extremities were highest in those taking a beta-blocker (4.1%). Those untreated or taking other therapies complained less often. Those patients taking a beta-blocker with ISA complained less often (3.1%) of cold extremities than those taking a beta-blocker without ISA (5.2%).
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  • 53
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 67-74 
    ISSN: 1432-1041
    Schlagwort(e): acetylsalicylic acid ; platelet function ; salicylate ; controlled release formulation ; single dosing ; continuous dosing ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The extent to which a controlled release acetylsalicylic acid (ASA) formulation inhibited platelet function has been evaluated in single and chronic dosing studies. In the single dose study, the platelet inhibitory effect of the controlled release formulation was compared with that of an equivalent dose of soluble ASA and an equimolar dose of sodium salicylate (SA). In the chronic dosing study, ASA dose-response curves for platelet function, including cyclooxygenase activity, were determined for various doses (20–1300 mg) of the controlled release (enteric coated pellets) ASA formulation taken by volunteers daily for one week. Platelet function was assessed by the degree of inhibition of aggregation for several aggregating agents, and the degree of inhibition of activity of platelet cyclooxygenase quantified by the estimation of malondialdehyde (MDA) production. Plasma ASA and SA concentrations were also determined in each study. The controlled release product inhibited platelet function to the same extent as an equimolar dose of soluble ASA, but did so with much lower and sometimes undetectable peak systemic plasma ASA concentrations. SA, the direct metabolite of aspirin, did not have any effect on platelet function. The ASA dose-platelet function response curves obtained from chronic dosing with the controlled release formulation appeared to be similar to those reported previously for the soluble product. The inhibition of platelet function appeared to be unrelated to plasma ASA concentrations.
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  • 54
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 115-117 
    ISSN: 1432-1041
    Schlagwort(e): benzodiazepine antagonist ; Ro 15-1788 ; healthy volunteers ; pharmacokinetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The pharmacokinetics of the selective benzodiazepine antagonist Ro 15-1788 has been studied in 6 healthy male volunteers following a single intravenous dose of 2.5 mg. The drug was only slightly bound to plasma proteins (40±8%, mean±SD). A negligible amount (〈0.2% of the dose) of unchanged drug was recovered in urine. Hepatic elimination was rapid, as shown by a short t1/2 of 0.9±0.2 h, and high total plasma and blood clearances of 691±216 ml/min and 716±199 ml/min, respectively. The fast decline of plasma levels from about 60 to 2 ng/ml accounts for the short-lasting reversal of benzodiazepine-induced sedation by Ro 15-1788.
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  • 55
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 335-339 
    ISSN: 1432-1041
    Schlagwort(e): transdihydrolisuride ; dopamine agonist ; pharmacokinetics ; pharmacodynamics ; prolactin levels ; side-effects ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Plasma levels and urinary excretion of the dopamine agonist, transdihydrolisuride (TDHL), were measured by radioimmunoassay in healthy male volunteers given TDHL 50 µg i.v. and oral doses of 200, 400 and 800 µg. Plasma prolactin was also measured by radioimmunoassay. Following i.v. injection, the concentration of TDHL declined with a half-life of 37±19 min. The total clearance was 38±27 ml/min/kg and the apparent volume of distribution was 1.3±0.4 l/kg. The bioavailability of oral TDHL was proportional to the dose; after 200, 400 and 800 µg the bioavailability was 20±25%, 31±24% and 48±26%. TDHL was almost totally metabolized and less than 0.5% of the dose was excreted unchanged in urine in 24 h. Plasma prolactin levels were depressed by 66±15%, 75±11% and 80±7% after TDHL 200 µg, 400 µg and 800 µg. The effect lasted for more than 12 h after the lowest dose and for more than 24 h after 400 and 800 µg. Side effects, mainly nausea and headache, only occurred at the two highest dose levels.
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  • 56
    ISSN: 1432-1041
    Schlagwort(e): molsidomine ; vasodilators ; pharmacokinetics ; pharmacodynamics ; dose-response relationship ; haemodynamics ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary In 12 healthy male volunteers, molsidomine 1, 2 and 4 mg i.v. increased resting heart rate and decreased systolic blood pressure, the latter still being affected after 8 hours. After single oral doses of 1 and 2 mg, systolic pressure tended to be reduced for 90 minutes and exercise heart rate tended to be increased. After oral treatment with 2 mg molsidomine three times daily for 1 week, the pharmacokinetic parameters and the effects on heart rate and blood pressure after the final dose were not different from those after the first dose. The terminal half-life was independent of dose and route of administration. Clearance and distribution volume were not dose-dependent. The bioavailability of a 2 mg oral dose of molsidomine was 44%. Inter-individual variation in heart rate, blood pressure and pharmacokinetics was observed.
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  • 57
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 287-289 
    ISSN: 1432-1041
    Schlagwort(e): pinacidil ; hypertension ; vasodilator ; patients ; side-effects
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary A new vasodilator drug, pinacidil, N″-cyano-N-4-pyridyl-N′-1, 2,2-trimethylpropylguanidine, was studied in an open trial in 15 patients with moderate to severe hypertension. Four patients received pinacidil monotherapy, and in 11 patients it was used with a diuretic or a beta-blocker. In all but one patient normotension was achieved with a mean daily pinacidil dose of 46.7 mg b.i.d. (range 20–100 mg). Side effects were few and were action-related. There was no evidence of early toxicity. Pinacidil is a promising new antihypertensive vasodilator, which deserves further clinical evaluation.
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  • 58
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 303-306 
    ISSN: 1432-1041
    Schlagwort(e): frusemide ; renal function ; ageing ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The effect of IV frusemide was studied in six healthy young (mean age 26.5 years, range 21–33) and six healthy old (mean age 72.8 years, range 66–80) volunteers. A 24-h urine collection before frusemide showed no difference in volume and sodium excretion, although the old excreted less potassium. Creatinine clearance was significantly reduced in the older subjects. After frusemide, 20 mg IV, the pattern of sodium and water excretion over a 5-h period was different in the two groups. The peak effect was greater in the young and occurred within the first 30 min, but was delayed to between 30 and 60 min in the old. Thus in the young the time for 50% of the total sodium and water to be excreted was half that in the old. This delay in sodium and water excretion was related to baseline creatinine clearance. However, the total water, sodium and potassium excreted in the 5 h after frusemide did not differ in the two groups. These results suggest that the renal effects of frusemide are different in healthy elderly subjects as compared to the young. The delayed and reduced peak response is consistent with fewer nephrons in the elderly kidney.
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  • 59
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 319-324 
    ISSN: 1432-1041
    Schlagwort(e): theophylline ; enprofylline ; terbutaline ; haemodynamic response ; adenosine antagonism ; healthy volunteers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The haemodynamic response to two xanthines, enprofylline and theophylline, was studied in 6 healthy male volunteers at rest, during exercise and in combination with the beta2-agonist, terbutaline. At rest the haemodynamic effects of both xanthines were small and were qualitatively different from each other. While theophylline exerted a “pressor” response, enprofylline seemed to have arterial dilating ability. During exercise both xanthines as compared to placebo were associated with a higher heart rate and in general with increased systolic blood pressure. In combination with terbutaline enprofylline and theophylline both increased systolic blood pressure more than placebo, i. e. they augmented the positive inotropic effect of terbutaline. The systolic blood pressure was higher after theophylline than enprofylline despite their equipotent bronchodilator activity. This may reflect different inotropic effects of the xanthines as well as a difference in their influence on the response to adenosine.
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  • 60
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 27 (1984), S. 325-328 
    ISSN: 1432-1041
    Schlagwort(e): theophylline ; sustained release ; pharmacokinetics ; chronic administration ; healthy volunteers ; plasma levels ; GCMS assay ; stable isotope technique
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The pharmacokinetics of a new sustained-release preparation of theophylline (Dilatrane à Action Prolongée capsules filled with homogenous microgranules) has been after its studied administration to 7 healthy volunteers at 8 p.m. in order to achieve therapeutic levels at night and in the morning. In separate trials the test dose of 500 or 600 mg was administered for 7 days, once daily at 8 p.m. Plasma theophylline levels were measured by capillary gas chromatography with a mass specific detector after pentylation, using internal standards labelled with stable isotopes (15N-1,3 and 13C-2 theophylline). The new sustained-release preparation showed a monophasic regular absorption phase with very low interindividual variability. After administration, the plasma level stayed within 80% of the peak levels for 8.5±1.5 h. There was a good correlation between the dose and the steady state plasma level (r=0.9587; p〈0.05). This preparation can be chronically administered once daily day at 8 p.m. in order to achieve a therapeutic level during the night and the morning, and to provide sufficient protection during the nycterohemeral period, with a once dose a day schedule.
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  • 61
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 59-66 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Araceae ; Hapaline ; Hapale ; Phymatarum ; Bucephalandra ; Flora of Borneo ; East Malaysia ; Sarawak
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract On the basis of newly collected and cultivated material full descriptions and illustrations are presented forHapaline appendiculata Ridl. andPhymatarum borneense M. Hotta.
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  • 62
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 67-71 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Scrophulariaceae ; Veronica fridericae spec. nova ; V. acrotheca ; V. farinosa ; V. armena ; V. multifida ; V. jacquinii ; V. caucasica ; V. filifolia ; V. oltensis ; Flora of Turkey
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Veronica fridericae spec. nova, described from the type locality in the S.E. Turkish province Van, is related toV. acrotheca andV. farinosa, both endemic to W. Iran. All 8 perennial species with pinnatifid leaves in S.W. Asia are presented in a key.
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  • 63
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 149-150 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Campanulaceae ; Campanula schimaniana spec. nova ; Flora of Afghanistan and of Pakistan
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Campanula schimaniana is a new species of sect.Campanula subsect.Rupestres, distributed in the westernmost mountains affected by monsoon.
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  • 64
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 151-153 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Compositae ; Asteraceae-Heliantheae ; Calea ; Chromosome numbers ; polyploidy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Chromosome numbers are reported for six taxa ofCalea, among them tetraploidC. septuplinervia, the only known polyploid inCalea s. str. The base chromosome number ofCalea is interpreted as x = 19.
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  • 65
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 155-163 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Leguminosae ; Fabaceae ; Caesalpinioideae ; Mimosoideae ; Faboideae ; Phaseolus coccineus ; Serological systematics ; seed proteins ; phytohaemagglutinin ; vicilin ; phaseolin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract An immunosystematical research was conducted on the seed proteins of 32 species ofFabaceae. By comparing all immunelectrophoretic patterns with the self reaction of a reference system (Phaseolus coccineus) all proteins detected have been identified and their distribution within the family has been analyzed. Half of the proteins identified inP. coccineus gave positive cross reactions with proteins present in all other species. Among this group are “protein I” and “phaseolin”. This result supports the homologization between phaseolin and vicilin. Among the other proteins, three are irregularly distributed throughout the family, and only three are restricted to a few taxa. This last group includes phytohaemagglutinin, which does not present any cross reaction outside the tribePhaseoleae.
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  • 66
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 209-220 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Triticum ; Elytrigia ; wheat ; Evolution ; genome ; karyotype
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The lengths of the A, B, and D genomes of common wheat,Triticum aestivum, were measured from the karyotype. Relative to the B genome, standardized as length 1.000, the lengths of the A and D genomes were 0.835 and 0.722, respectively. The lengths of the chromosome arms in the A and D genomes were then multiplied by the appropriate constants so that the total lengths of each genome also equalled 1.000. These calculations revealed that homoeologous chromosomes in wheat, with a few exceptions, have similar sizes and arm ratios. The arm lengths of the three homoeologues in each homoeologous group were then averaged. These average chromosomes turned out to be remarkably similar, in size and arm ratio, to their homoeologues in the E genome ofElytrigia elongata. This evidence and data on cross-compatibility and morphological characteristics suggested that the genusTriticum is a result of adaptive radiation from the perennial genusElytrigia, specifically from the complex of species possessing the E genome or one closely related to it.
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  • 67
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 307-314 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Geraniaceae ; Erodium ; Monsonia ; Geranium ; Taxonomic revision ; Flora of Egypt
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A key is provided for the 14Erodium species of the Egyptian flora. The important differential chracters of leaf, inflorescence, flower, and fruit are discussed and illustrated.
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  • 68
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 144 (1984), S. 315-320 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Fabaceae ; Lupinus palaestinus ; L. pilosus ; Breeding system ; insect induced self pollination
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Significant increase of pod production occurs inLupinus palaestinus Boiss. andL. pilosus Murr. following insect visits. The cause of this increase is investigated through (1) examination of the biology of pollination, (2) examination of pod production under various pollination conditions, (3) examination of cross pollination by genetical markers. All data strongly suggest that “Insect Induced Self Pollination” is the main factor in the increase of pod production of these species in nature.
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  • 69
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 1-13 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Triticum aestivum ; Aegilops longissima ; Cytogenetics ; homoeologous relationships ; chromosome substitutions ; translocations
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The relationships of three wheat-Aegilops longissima chromosome addition lines A, C, and D with homoeologous wheat chromosomes were studied in PMC meiosis. Substitutions of alien chromosome A for wheat chromosome 6 B, chromosome C for 1 B and chromosome D for 4 B were obtained. The production of 4 BS/C and 7 BS/D chromosome translocations indicated cytogenetic relationships of C partially to homoeologous wheat chromosomes of group 1 and 4, and D partially to homoeologous wheat chromosomes of group 4 and 7.
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  • 70
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 15-28 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Gramineae ; Hordeum spontaneum ; Wild gene pool ; factor analysis ; numerical taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Samples from 11 populations of wild barley,Hordeum spontaneum, from Israel, were examined for morphological variation in a “common garden” plot design. Earliness traits had the highest between population variation of all traits studied. No relationship was found between dimensions of leaves and size of seeds.—Using numerical taxonomy methods, four races were found, which correspond to the geographical and environmental range of the species in Israel. It is concluded thatH. spontaneum shows a well developed tendency toward formation of highly adaptive races rather than exhibiting clinical variation.
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  • 71
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Annonaceae ; Porcelia goyazensis ; Annona reticulata ; Winteraceae ; Drimys brasiliensis ; Giemsa C-banding ; structural heterozygosity ; karyotype evolution in tropical woody plants
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract InPorcelia goyazensis (2n = 18) Giemsa C-banding patterns differ from those ofAnnona reticulata (2n = 14) and reveal structural heterozygosity. The amplitude of karyological variation in theAnnonaceae is greater than expected for a “primitive” woody family. In a comparison with other tropical angiosperm groups, the highly differentiated karyotype ofDrimys brasiliensis (2n = 86) is interpreted as being the end-point of numerous karyological changes.
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  • 72
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 55-77 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Acanthaceae ; Bignoniaceae ; Bombacaceae ; Caesalpiniaceae ; Caryocaraceae ; Chrysobalanaceae ; Fabaceae ; Lobeliaceae ; Lythraceae ; Malvaceae ; Marcgraviaceae ; Mimosaceae ; Musaceae ; Onagraceae ; Orchidaceae ; Passifloraceae ; Proteaceae ; Rubiaceae ; Solanaceae ; Tiliaceae ; Zingiberaceae ; Flower nectar ; amino acids ; sugars ; evolutionary significance ; pollination biology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Individual amino acids and sugars from flower nectar of 32 plant species with different pollination systems were quantified and compared. Data show that there is no correlation between sugar and amino acid concentration. Furthermore there is no correlation between composition and concentration of amino acids and evolutionary advancement, nor any direct relation with pollination systems. However, higher sugar concentrations are often linked with more advanced morphological characters. Nectars from pierced or damaged flowers or nectars contaminated with pollen exhibit modifications and increases in amino acid composition. The presence of proline probably indicates such pollen contamination. Most pollinating animals depend on flower nectar in their energetic requirements, yet innumerable alternative amino acid and protein sources exist. Future research has to consider the relationship between nutritional requirements of pollinating animals and dependence on flower nectars.
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  • 73
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 135-153 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Asteraceae ; Senecio vulgaris ; S. vernalis ; Autotetraploidy ; self-compatibility ; annual weeds
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Senecio vulgaris L. (2n = 40) is suggested to be of autotetraploid origin fromS. vernalis Waldst. & Kit. (2n = 20). This conclusion is based on results obtained from experimental hybridisations and cytological observations, and the consideration of morphological affinities, patterns of geographical distribution and hybrid formation under natural conditions. The morphological differences between the two species are related to a difference in the breeding system. WhilstS. vernalis is self-incompatible,S. vulgaris is self-compatible and strongly self-pollinating. Equally, other self-pollinating taxa traditionally associated withS. vulgaris are shown to have evolved independently from outbreeding relatives. Within a narrow frame of relationship, annual weeds have evolved in different cytotaxonomic circumstances.
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  • 74
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 165-168 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Solanaceae ; Datura innoxia ; Haploidy ; diploidy ; triploidy ; tetraploidy ; hexaploidy ; amino acid composition
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract In haploid, diploid, triploid, tetraploid and hexaploid cytotypes of the scopalamine-yieldingDatura innoxia, the amino acid profiles were studied. The results suggest that the amino acid composition is influenced quantitatively by increasing ploidy levels, but in an irregular way.
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  • 75
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 183-191 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Saxifragales ; Cunoniales ; Brunelliaceae ; Brunellia comocladiifolia ; B. mexicana ; Theales ; Caryocaraceae ; Caryocar brasiliense ; C. microcarpum ; C. villosum ; Karyosystematics ; paleopolyploidy ; tropical woody plants
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Chromosome numbers are polyploid, 2n = 28 inBrunellia comocladiifolia andB. mexicana, and 2n = 46 inCaryocar brasiliense, C. microcarpum andC. villosum. The chromosome are small in both genera, with a length of ca. 1,6-0,4µm. Interphase nuclei correspond to the prochromosomal and the chromocentric type, respectively. This is in conformance with the systematic placement ofBrunelliaceae intoCunoniales, and ofCaryocaraceae intoTheales. Brunellia exhibits affinities to various other orders ofRosidae (andHamamelididae), and is suggested to be primarily apetalous. On a comparative basis, the chromosome numbers found in both families are interpreted as paleopolyploid (4 x and 6 x). This apparently is in correspondence with their rather primitive features, systematic isolation, relatively depauperate status, and evidently great age.
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  • 76
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 193-201 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Ranunculaceae ; Aconitum ; Seed morphology ; seed coat SEM microcharacteristics ; taxonomic importance ; adaptative ecological significance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The seed coat morphology, investigated in taxa representative of the main European groups ofAconitum, are in good agreement with the current taxonomy of the genus. The seed coat microcharacteristics (warty epidermal cells) are very constant. There is a trend for the reduction of longitudinal wings on the edges concomitant with the development of ridges and transverse wings on the faces. Another morphological progression leads from smooth to rugulose and eventually to transverse wing-bearing seed faces. A working hypothesis suggests an ecological adaptative significance to these changes.
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  • 77
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 223-226 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Theaceae ; Camellia japonica ; Allozymes ; polyploidy ; origin of cultivars
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Electrophoretic examination of allozymes from 189Camellia japonica cultivars revealed some banding patterns not explainable by codominant diploid genetics. At several loci encoding dimeric enzymes, 5 and 6 banded patterns were observed in 7 cultivars. These patterns are interpreted as resulting from triploidy or aneuploidy, where three variant alleles code for products which are electrophoretically distinguishable and associate to form three homodimers and three heterodimers. The presence of allozyme multiplicity in these clones suggests a sexual rather than a somatic mode of triploid origin.
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  • 78
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 243-258 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Asteraceae ; Lactuceae ; Microseris ; Canalized numbers ; additive polygenes ; evolutionary genetics ; pappus parts ; leaf shape ; isoenzymes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract CrossingMicroseris pygmaea (10 pappus parts) withM. bigelovii (5 pappus parts) results in hybrids with variable pappus part numbers between 5 and 10. Previous work has shown that a system of four additively acting genes determines the average pappus part numbers of these hybrids. In hybrid B87 two genes have a 10-determining and a 5-determining allele each, two others a 5-determining and a null (inactive or missing) allele. Genetic linkage of one of the latter with the enzyme geneEsterase-1 and the leaf shape genespatulate leaves has been demonstrated. Here we demonstrate linkage between one of the two 10-determining genes and the enzyme locusEsterase- Y/B. The genotypes in the pappus part system of many specimens can now be fully determined. This is a major advance for the analysis of the evolution of this additive polygenic system.
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  • 79
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Caryophyllaceae ; Silene latifolia ; S. alba ; S. pratensis ; Geographic variation ; racial differentiation ; clines ; morphological variation ; flavone glycosylation genes ; principal components analysis ; cluster analysis ; Flora of Europe
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Morphological and biochemical data were analysed from 30 greenhouse-grown populations of EuropeanSilene latifolia. Six separate character sets (flavones, seed, pollen, capsules, male and female flower morphology) were used in the analyses. There was broad-scale congruence between trends of geographic variation in most character sets, with the populations being assigned to western (or southern and western) and eastern clusters. The eastern and western clusters abut along a transition zone that runs roughly from Belgium to the northern Balkans; this zone represents a region of relatively rapid change and contains populations intermediate between the eastern and western clusters. Variation in flower morphology was weak and discordant with variation in the other character sets. The origin and maintenance of the variation pattern is discussed in terms of migrational history and “hybrid zones”.
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  • 80
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 291-309 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Cruciferae ; Brassicaceae ; Biscutella variegata complex ; B. laevigata complex ; Chromosome numbers ; variation ; aneuploidy and polyploidy ; chromosomal imbalance ; protogyny ; inbreeders and outbreeders
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Chromosome counts were determined for 46 populations ofBiscutella representing 28 taxa. The genus was found to contain diploid taxa with 2n = 12, 16 and 18, tetraploid taxa with 2n = 36 and hexaploid taxa having 2n = 54.B. laevigata L. s. l. consists of diploid and tetraploid populations which are poorly differentiated morphologically. TetraploidB. laevigata s. l. and hexaploidB. variegata Boiss. & Reuter (s. l.) are characterized by chromosomal instability. The variation in chromosome numbers and the occurrence of polyploidy is discussed in relation to the taxonomy of the genus. An investigation of the breeding system showed that most of the annual species were self-compatible and partly inbreeding and most of the perennial species self-incompatible and, therefore, outbreeding, while one annual species,B. cichoriifolia Loisel., showed both systems.
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  • 81
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 1-11 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Liliaceae ; Hyacinthaceae ; Scilla peruviana ; Gene mapping ; restriction enzymes ; ribosomal RNA genes ; rRNA/DNA hybridization ; polyploidy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Scilla peruviana biotypes have different chromosome numbers due to changes in the nucleolar chromosomes and polyploidy. We have examined two diploid (2n = 15 and 2n = 16) and two tetraploid biotypes (2n = 28 and 2n = 32). From the results of rRNA/DNA filter hybridizations it appears that rDNA percentages of the diploid biotypes are, approximately, 2.2-fold higher than those of the tetraploid biotypes. To examine the rRNA gene structure we have utilizedSouthern blot hybridization after DNA digestions with three restriction enzymes: Eco RI, Hind III and Bam HI. From the band analysis of both single and double digestions it has been possible to reveal the presence, in the diploid biotypes, of three gene types, heterogeneous both for length and for nucleotide sequences in the external spacer. The three rRNA genes are 12 600, 12 700, and 12 800 base pairs long and they have a different position of the Hind III sites in the external spacer. On the other hand, a single gene type of 12 600 base pairs, identical to the first type of the diploid biotypes, surprisingly exists in the tetraploid biotypes. Considerations on the rRNA gene regulation and evolution are made.
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  • 82
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 13-30 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Rutaceae ; Chromosome number ; karyotaxonomy ; base number ; karyotype variation ; literature critique
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Detailed chromosome counts have been made in 61 species, belonging to 33 genera ofRutaceae. 30 of these species are reported here for the first time. For 18 species at least one previous publication gives a chromosome number differing from that reported here. Such discrepancies are, in most cases, due to errors in counting or identification of the material. By critically reviewing the literature on each particular case, it appears possible to eliminate most of the false data. On the basis of the present results, the base number x = 10 is proposed for the genusRuta.
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  • 83
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 47-55 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Annonaceae ; Chromosomes ; polyploidy ; karyosystematics ; cytotaxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Information and illustrations on somatic chromosomes, structure of interphase nuclei and hair development are presented for 9 genera and 14 species ofAnnonaceae. A few suggestions tend to improve the unsatisfactory current classification. The spectrum of polyploids found in the family ranges from neo- to meso- and paleopolyploids.
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  • 84
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 87-104 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Iridaceae ; Sisyrinchieae ; Tigridieae ; Trimezieae ; Basic numbers ; chromosome size ; karyotypes ; polyploidy ; karyotypic asymmetry ; bimodality ; DNA increase ; chromosome evolution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Although the South AmericanIridaceae are cytologically diverse, three tribes are distinguishable on the basis of karyotype morphology. TheSisyrinchieae andTrimezieae have variable basic numbers, ploidy levels and chromosome sizes, while theTigridieae are characterized by a relatively uniform basic number and bimodal karyotype. Changes in chromosome size within genera may suggest fluctuations in their DNA amount with latitude and altitude, particularly inSisyrinchium. The results are considered in terms of opportunities for more detailed research.
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  • 85
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 117-121 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Embryology ; megagametophyte ; antipodals proliferation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The structure of the grasses megagametophyte is considered to be characteristic enough as to deserve a particular place in the megagametophyte typology. Furthermore, it is compared with those of other Monocotyledonous families to point out embryological affinities.
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  • 86
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 105-116 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Myrtales ; Oliniaceae ; Olinia ; Embryology ; reproductive anatomy ; systematics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Two of the five species ofOliniaceae (Olinia emarginata andO. ventosa), a monotypic and problematic family of theMyrtales, were investigated embryologically.Oliniaceae clearly agree with otherMyrtales in their basic embryological characteristics, and are characterized further by having an ephemeral endothecium, a campylotropous ovule, and a thick, three-five-layered, outer integument. A combination of these three characteristic features is unknown elsewhere inMyrtales, so that embryological features do not support a close relationship with any other member of the order. Shared distinctive anther characteristics (i.e. ephemeral endothecium) suggest thatOliniaceae are derived from the common ancestor ofCrypteroniaceae s. str.,Rhynchocalycaceae, Alzateaceae, andPenaeaceae.
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  • 87
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 141-143 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Lamiaceae ; Salvia tuxtlensis spec. nova ; Flora of Mexico
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Salvia tuxtlensis, sp. n., is immediately recognized by its semipersistent bracts and yellow flowers. Its affinities are not clear. It is endemic to the Soteapan area in the Sierra de Los Tuxtlas, in Veracruz, Mexico.
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  • 88
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 123-139 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Boraginaceae ; Rochelia ; Rochelia disperma ; Gynoecial development ; fruit development ; pseudomonomery ; systematics ; evolutionary trends
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The ontogeny of the gynoecium ofRochelia disperma has been investigated by LM and SEM. From the floral apex only one carpel primordium arises abaxially and eventually shifts into a subterminal position. Neither an initial stadium of a second carpel nor an adaxial vascular strand in gynobase and style could be observed. InR. stylaris two vascular strands run through the style and two undifferentiated lobes in adaxial position may be regarded as rudimentary mericarps. Only from comparison with related taxa the conclusion can be drawn thatRochelia is really pseudomonomerous, more so inR. disperma than inR. stylaris. The primary gynoecial bulge splits up into three parts inR. disperma: style/stigma, nutlets with gynobase, and disc. While the mericarps originate in mostBoraginoideae from the symplicate region and the ascidiate one is restricted to the very basal parts, inR. disperma the ascidiate part extends and forms the nutlets. The hood-shaped mouth of the carpel (the plicate zone) is closed to a triangular slit in lateral position, the stigma. The nutlets are triangular with broad base and do not surround the adaxial part of the gynobase inR. disperma, R. persica, R. bungei, R. stylaris, andR. macrocalyx. In contrast,R. peduncularis, R. cardiosepala, andR. cancellata have nutlets clasping the gynobase; they may be more closely related than was assumed up to now. The glochids ofRochelia are fascicled unicellular hairs (with different shapes) and not emergences as in theCynoglosseae. There is an evolutionary trend towards fruit formation with only one mericarp, especially inR. disperma.
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  • 89
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 171-179 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Rosaceae ; Fragaria ; Restitution ; microsporogenesis ; polyploidy ; evolution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Double restitution has been observed cytologically for the first time in microsporogenesis of a F1 hybridFragaria virginiana ×F. chiloensis ♂. Restitution is probably due to irregularities affecting the spindle mechanism. Single or double restitution may depend upon the duration of the effect or upon the stage of meiosis affected. The occurrence of triades is indicative of a possible intracellular diversity. Although the reason which may cause restitution remains to be ascertained, maternal inheritance indicates an extrachromosomal cause.
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  • 90
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 181-195 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Myrtales ; Penaeaceae ; Penaea ; Saltera ; Embryology ; reproductive anatomy ; systematics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Two species ofPenaeaceae (Penaea mucronata andSaltera sarcocolla), a unique South African family ofMyrtales, were investigated embryologically.Penaeaceae clearly agrees with otherMyrtales in its basic embryological characteristics, and further is characterized by its highly specialized features: ephemeral endothecium, 16-nucleatePenaea-type embryo sac, and unique ovular form. A wider range of affinities of families includingPenaeaceae, Oliniaceae, Rhynchocalycaceae, Alzateaceae, andCrypteroniaceae sensu stricto, as well as a possible common divergence from an ancestral line leading toLythraceae and/orMelastomataceae, are discussed on embryological and other grounds.
    Materialart: Digitale Medien
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  • 91
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 197-214 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Cactaceae ; Epidermis ; parallelocytic stomata ; stomatal types ; classification ; survey
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The stomatal types (i.e. the arrangement of epidermal cells in the vicinity of a stomatal pore in superficial view) have been examined in more than 150 taxa ofCactaceae, mostly using documented material. Preparations have been made by mazerating pieces of tissue with modified Jeffrey's Solution and staining with chlore-zinc-jodine.—The examined members of the subfamilyCactoideae showed parallelocytic stomata with only minor deviations in a number of cases. Members of the subfamiliesPereskioideae andOpuntioideae show parallelocytic stomata on the leaves, but the stomatas of the stem represent a different type, which apparently is not yet described. It is termed opuntioid here. In most cases the stomata are superficial but a few taxa show markedly sunken or “hidden” stomata.—In taxa of the subfamiliesPereskioideae andOpuntioideae the stomata are generally oriented parallel to the stem axis with only minor deviations. The stomata of taxa of the subfamilyCactoideae do in general not show a particular orientation with the notable exception of a number of epiphytic genera from the tribeHylocereeae.—The results of these investigations in general coincide well with the generic classification of theCactaceae byHunt (1967). A few cases where stomatal characters suggest a differing classification merit further investigations.—Additionally, the possibilities to distinguish between paracytic and parallelocytic stomata are discussed and an amended definition for the latter is given.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 92
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 265-267 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Loranthaceae ; Phthirusa adunca ; Anther wall ; endothecial thickenings
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The thickenings in the anther wall ofPhthirusa adunca are confined to the endothecium. This observation resembles the previous report onP. pyrifolia.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 93
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 146 (1984), S. 225-248 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Scrophulariaceae ; Campanulaceae ; Canarina ; Isoplexis ; Bird pollination ; ornithophily ; Flora of Macaronesia ; Canary Islands
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract (1) On the Canary Islands and Madeira typical bird-flowers occur in at least twelve species of six genera, although true flower-birds are absent. This inconsistency is in part elucidated by field observations on exotic and wild plants of Tenerife. —(2) In the Botanical Garden of Orotava it could be observed that various ornithophilous plants, which were introduced there, were visited by indigenous birds for nectar and in one case (Orthostemon) for food tissue. Of the three bird species involved, an endemic race of Chiffchaff (Phylloscopus collybita) and resident Blackcaps (Sylvia atricapilla) exploit, and pollinate, flowers legitimously, while the Wild Canary (Serinus canaria) is predominantly a destructive nectar robber. —(3) The insular Chiffchaff also proved to be a regular pollinator in the wild, at least ofCanarina canariensis andIsoplexis canariensis, two ornithophilous paleoendemics. Ornithophily, thus, is naturally practised on the island, though by birds basically insectivorous. —(4) A list of Macaronesian plants bearing the more or less complete ornithophilous syndrome is presented, including newly recognizedTeucrium heterophyllum andScrophularia calliantha. —(5) On biogeographical and faunistic grounds it is presumed that the modern visitors of Canarian bird flowers are secondary rather than the original partners of the continental tertiary flora in which these plants originated. Palearctic immigrants, when becoming resident on the islands during and since the Pleistocene, adopted facultative nectar feeding, entering an “orphaned” food niche. Casual flower visits in Europe suggest a certain predisposition of the Chiffchaff and the Blackcap for the exploitation of flowers. — (6) The ability of unspecialized birds to acquire nectardrinking spontaneously and to pass this habit on to their offspring, is demonstrated by a population of Tree Sparrows (Passer montanus) which have visited ornithophilousKniphofia (Liliaceae) in Berlin for several years.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 94
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 147 (1984), S. 1-27 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Gramineae ; Dispersal ; hygroscopic movements ; trypanocarpy ; diaspore ecology ; cerrado vegetation ; Flora of Brazil
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract 28 grass species from one hectare of cerrado vegetation in Botucatu, State of São Paulo, were studied with regard to the morphology and dispersal of their fruits. 13 species have dispersal units with smooth surfaces which are predominantly dispersed by big herbivorous mammals or birds which swallow them together with their food, e.g., during grazing (accidental endozoochory). On the other hand, smaller animals, including birds, also feed directly on the grains; some of them may escape trituration and digestion or may be even stored (synzoochory). 11 species are principally epizoochorous: 8 of these are ± exclusively adapted to epizoochory, adhering to the animals by scabrid awns or sharply pointed calli, while the rest behave as epizoochores and anemochores. 4 other species are predominantly anemochorous with their dispersal units bearing soft hairs, sometimes together with very small scabrid awns; in a wet state they also can adhere to animals (occasional epizoochory). Beside this, most grass fruits can behave as passive ballists, as passing animals, wind and rain may cause their dispersal units to fall to the ground (passive autochory). — Among the 28 species, 12 have dispersal units which are awned. In 7 of them the awns are spirally twisted; the base of the dispersal unit runs out into a sharply pointed callus and has harpoone-like hairs. These awns show hygroscopical movements which may lead to a drilling of the basal part of the dispersal unit into the sandy cerrado soil. This trypanocarpy is important for establishment but without function for dispersal.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 95
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 147 (1984), S. 55-61 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Bombacaceae ; Malvaceae ; Hampea nutricia ; Seed morphology and anatomy ; aril
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The mature seeds ofHampea nutricia are glabrous, ovoid, arillate and dark tan in colour. Longitudinal streaks on the seed surface correspond to the underlying integumentary vascular strands. Testa and tegmen are derived from the outer and inner integuments, respectively. The outer epidermis of the tegmen forms a palisade-like macrosclereid layer, the inner epidermis a fringe layer. The endosperm is single-layered and also fills the space between the two cotyledons. The embryo is nearly straight, gland-dotted; it has asymmetrical and folded cotyledons, and gossypol ducts. Systematic position ofHampea is discussed and its placement inMalvaceae is supported.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 96
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 147 (1984), S. 63-78 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Exine morphology ; origin of sporophytic self-incompatibility ; palynology ; pollen wall
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract In angiosperm pollen the reticulate-perforate exine sculpturing is associated with sporophytic self-incompatibility (S.S.I.) and imperforate and microperforate exine sculpturing is associated with gametophytic self-incompatibility. The earliest unequivocal angiosperm pollen conforms to exine morphology of pollen from plants with S.S.I. The orgin of S.S.I. is hypothesized to have coincided with the appearance of what is now the earliest recognizable angiosperm pollen. Other angiosperm characteristics correlated with S.I., functional stigmatic areas, large showy flowers (or aggregated inflorescences), and passive seed dispersal, provide some insight into the biological aspects of the earliest angiosperms.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 97
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 147 (1984), S. 79-90 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Onagraceae ; Oenothera hookeri ; Oe. suaveolens ; Megasporogenesis ; inheritance of callose pattern and polarity of embryo sac development ; embryology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The pattern of callose formation in meiotic cell walls and the order of megaspore degeneration and polarity during embryo sac development are investigated in F2-plants ofOe. hookeri ×suaveolens and the reciprocal cross. All investigated characters are variable between the ovules in the same ovary. Plants differ in the frequency of the types of callose pattern and polarity of the embryo sacs. In segregating progenies different combinations of both characters are found. The genetic basis of the polarity phenomena during the embryo sac development is discussed. In our material no correlation can be seen between the callose pattern in the surrounding wall of the meiotic cell and the development of polarity in the later stages.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 98
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 147 (1984), S. 103-118 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Limonium ; Plumbaginaceae ; Numerical taxonomy ; variation ; agamospermy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A taxometric analysis ofLimonium species in Western Europe has provided evidence for the subgeneric groupings proposed by other authors. A cluster analysis suggests that the origin of sexual and agamospermous species has taken place separately. Sexual and agamospermous species are usually clustered separately. The lack of a sexual process in many agamospermous species, as indicated by the distribution of incompatibility morphs and by very low pollen fertility, suggests that the evolution of sexual and agamospermous taxa has been by different processes. It is suggested that following the origin of agamospermous species or species groups by hybridisation, subsequent evolution in the agamospermous taxa has occurred by asexual means. Evidence from the distribution of pollen/stigma incompatibility morphs, especially the existence of self-compatible agamospermous species supports this hypothesis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 99
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 147 (1984), S. 91-102 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Onagraceae ; Clarkia xantiana ; Electrophoresis ; isozymes ; phylogenetic models
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Electrophoretic variation in isozymes coded by 40 loci was examined in two self-pollinating populations, one with white and the other with pink flowering plants, and four outcrossing populations ofClarkia xantiana (Onagraceae) native to California. The study was carried out to test theMoore & Lewis (1965) hypothesis that the pink selfer originated from the sympatric outcrossing population and then gave rise to the white selfer. The hypothesis could be rejected if one or the other selfer was more similar genetically to an allopatric population than to the sympatric one. Both selfers were monomorphic at all loci whereas the outcrossing populations were polymorphic at nearly half of them. The two selfers had the same genes at 32 loci but had different ones at eight loci. The pink selfer was not more similar to the allopatric populations than to the sympatric one, consistent with theMoore & Lewis model. The evidence also supported their proposal that the white selfer originated from the pink one and not independently. The electrophoretic evidence was valuable because it permitted qualitative comparisons (presence versus absence of particular alleles) between the selfer and the several outcrossing populations; such analysis was not previously possible because the latter populations are morphologically and cytologically similar.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 100
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 147 (1984), S. 119-123 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Melastomataceae ; Nodal and petiolar vascularization ; common gap and split laterals ; flank bridge ; cortical bundles
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The nodal anatomy inMelastomataceae is variable. The (two times) unilacunar one trace type is wide-spread. In addition, species ofHeterocentron and ofTribouchina exhibit one pair of common gaps with split laterals. Others possess a distinct “flank bridge” of vascular tissue. Species with internodes quadrangular and four-winged in transsect exhibit up to five concentric cortical bundles per wing; they are involved in both petiolar vascularization and formation of flank bridges.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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