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  • Osteoporosis
  • Springer  (33)
  • Blackwell Publishing Ltd
  • De Gruyter
  • MDPI Publishing
  • National Academy of Sciences
  • 1980-1984  (28)
  • 1965-1969  (5)
  • 1935-1939
Collection
Publisher
  • Springer  (33)
  • Blackwell Publishing Ltd
  • De Gruyter
  • MDPI Publishing
  • National Academy of Sciences
Years
Year
  • 1
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    Calcified tissue international 36 (1984), S. S129 
    ISSN: 1432-0827
    Keywords: Bone mass ; Exercise ; Aging women ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Physical activity is an important stimulus in the prevention of bone involution. Bilateral bone mineral mass and width of the radius, ulna, and humerus were measured by single photon absorptiometry on 200 women between the ages of 35 and 65 over a 3–4 year period. Two groups were formed: 80 in a control group and 120 in a physical activity group exercising 45 min/day, 3 days/week. The control and physical activity groups were similar in age, height, weight, and level of physical fitness at the beginning of the study. The control group lost bone mineral mass at a rate similar to that of the general population. The left radius bone mineral declined 2.44% per year. Similar rates of decline were observed in the other bones measured. The physical activity group increased in fitness by 13% in the first year of the study. The bone mineral mass of the exercise group declined the first year and then increased; thereby the bone mineral data for the exercise group was analyzed in two sets. During the first year of the program, a decline of 3.77% in bone mineral mass of the left radius, a significantly greater loss than that of the control group, was observed. Decline rates were similar in the other bones measured. In the second and third years, bone mineral mass of the left radius increased by 1.39% per year, and the rate of change was significantly different from that of the control group. There were similar increases in the other bones measured. The data from this study support the importance of physical activity in the prevention of bone mineral loss in the aging female.
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  • 2
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    Calcified tissue international 36 (1984), S. 302-307 
    ISSN: 1432-0827
    Keywords: Metabolism ; pH ; Fluorosis ; Osteoporosis ; Toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The influence of gastric acidity on the absorption of intragastrically administered fluoride was investigated in rats. Intact animals were pretreated with atropine or cimetidine to reduce gastric acid secretion or were given fluoride in NaHCO3 to reduce the acidity of the gastric contents. Compared with pentagastrin-treated animals or animals that received fluoride in 0.1 N HCl, their rate of fluoride absorption was markedly reduced as judged by lower plasma fluoride concentrations and areas under the time-plasma concentration curves, especially during the first hour after dosing. In crossover studies with the stomachs isolatedin situ, fluoride absorption was at least 50% faster from a pH 2.1 buffer compared with its absorption from a pH 7.1 buffer. The findings are consistent with the hypothesis that fluoride is absorbed from the gastric lumen principally as the undissociated molecule, HF. The results may contribute to a more complete understanding of acute fluoride toxicity, the development of dental fluorosis and, perhaps, the use of fluoride in the treatment of osteoporosis.
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  • 3
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    Calcified tissue international 36 (1984), S. 431-434 
    ISSN: 1432-0827
    Keywords: Bendroflumethiazide ; Hydrochlorothiazide ; Calcium hydroxyapatite ; Hydrolysis ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Inhibition of dissolution of calcium hydroxyapatite in the presence of bendroflumethiazide, Centyl®, and of hydrochlorothiazide has been investigated. The former compound has a pronounced larger inhibitory effect than the latter. The trifluormethyl group in bendroflumethiazide has been shown to hydrolyze, with the release of fluoride and hydrogen ions, presumably forming a carboxylic acid. The inhibitory effect of hydrolyzed bendroflumethiazide is found to be similar to the effect of a potassium fluoride solution with the same fluoride ion concentration, as measured by a fluoride selective ion electrode.
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  • 4
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Renal osteodystrophy ; Fractures ; Bones and bone disease ; Absorptiometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Dual-photon absorptiometry (153Gd) was used to measure bone mineral of the total body and major anatomical areas. Patients with osteoporosis (♂=11, ♀=18) and with renal osteodystrophy (n=17) were significantly below (20%) normal females (n=72) and males (n=13) at most sites. In the osteoporotic patients, but not the renal patients, there was preferential osteopenia of the spine. Bone loss in all anatomical areas became evident after the menopause with an annual loss rate of about 0.7%.
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  • 5
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    Calcified tissue international 36 (1984), S. S56 
    ISSN: 1432-0827
    Keywords: Mechanical strain ; Bone remodeling ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Mechanical function has always been acknowledged to have a significant, continuing but hitherto unquantified influence on bone remodeling. The structural objective of this relationship is presumably to ensure that, at each location throughout the skeleton, there is sufficient bone tissue, appropriately placed, to withstand functional load-bearing without damage. The architectural modifications necessary to achieve and maintain this structural competence are made by the coordinated remodeling activity of populations of osteoblasts and osteoclasts. The specific structure-function objectives at each location remain undefined, as are the mechanisms by which tissue loading is transduced into cellular control. The remodeling responses following a variety of experimental alterations in bones' strain environment are presented. Their significance to the process of remodeling control is discussed, and a scheme for the interaction of mechanical and hormonal influences proposed.
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  • 6
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    Calcified tissue international 36 (1984), S. 341-343 
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Coherence Therapy ; Histomorphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Five patients suffering from osteoporosis were subjected to from three to eight cycles of a form of Coherence Therapy for Osteoporosis (1) used at this center. Assessment of the patients' trabecular bone remodeling activity as measured by histomorphometric analyses of trans-iliac crest bone biopsies showed a marked improvement.
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  • 7
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    Calcified tissue international 36 (1984), S. 725-728 
    ISSN: 1432-0827
    Keywords: Race ; Osteoporosis ; Calcitonin ; Katacalcin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Profound racial differences exist in the incidence of osteoporosis, particularly in women. To investigate possible underlying reasons for this, we have measured the circulating levels of calcitonin (iCT), a bone-protecting hormone, and its flanking peptide, katacalcin (iKC), in black Gambian and white British populations. Whilst sex differences in both peptides were observed, with males having higher levels than females, the most striking finding was that white women have the lowest iCT levels. This important observation may explain, at least in part, why osteoporosis is particularly a disease of white, postmenopausal women.
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  • 8
    ISSN: 1432-0827
    Keywords: Fracture ; (Glucocorticoid ; 1,25(OH)2D3 ; Osteoporosis ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A closed tibial fracture, which was controlled by an intramedullary stainless steel pin, was created in 16 rabbits. Eight rabbits were treated with 75 ng of 1,25(OH)2D3 daily as subcutaneous (s.c.) injections. After three weeks, the fractured tibia resisted a force of 101,7±21.0 Newtons in the control group and 57.3±8.0 Newtons in animals given 1,25(OH)2D3 (m±SE,P〈0.05). In another group of eight rabbits, the left hindleg was immobilized in a plastic splint. Four rabbits were given 75 ng of 1,25(OH)2D3/day s.c. and the effect of immobilization was studied on the calcaneus. Bone ash/cm3 of the calcaneus on the immobilized side was decreased by 11±2% in control rabbits and by 20±2% in the group treated with 1,25(OH)2D3 indicating a more advanced immobilization osteoporosis (m±SE,P〈0.05), which was also demonstrated by studies of bone density. Eighteen rabbits were used in a study of the effects of 1,25(OH)2D3 on the development of prednisolone osteoporosis. The dose of prednisolone was 2.5 mg per day, given by the oral route. After four months, the density of the femur was 1.53±0.02 g/cm2 in control rabbits and 1.42±0.01 in prednisolonetreated animals (P〈0.01). In rabbits additionally given 1,25(OH)2D3, the mean value for bone density was further lowered (n.s.). It appears that 1,25(OH)2D3 exaggerates disuse osteoporosis and prednisolone osteoporosis and impairs fracture healing in rabbits. These results differ from what has been shown earlier with 1,25(OH)2D3 treatment in the rat.
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  • 9
    ISSN: 1432-0827
    Keywords: 99mTc-pyrophosphate ; Bone metabolism ; Osteoporosis ; Osteomalacia ; Hyperparathyroidism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The retention of99mTc-labeled pyrophosphate (PPi) at 24 h was measured in 235 patients, 119 of whom had a normal bone metabolism. The mean retention in the group of normal subjects is 52% of the injected dose. Reproducibility of the measurement in a given person is 5.5% coefficient of variation (CV). The value depends strongly on sex (higher in males) and age (higher with increasing age, especially in cortical bone). Retention increases slowly with the decrease in glomerular filtration rate (GFR) between 50 and 120 ml/min; it rises very rapidly with values below 50 ml/min. The slowing down of the GFR with age does not account for the increase in PPi retention with age. When expressed as a percentage of the expected value for sex and age, retention is frequently low in osteoporosis (P〈.001), more so when urinary hydroxyproline is low; it is normal or high in osteomalacia, and in some cases rises after vitamin D treatment is started; it is high in hyperparathyroidism (P〈.01). The PPi retention is correlated with bone calcium accretion rate, alkaline phosphatase level, and above all, the urinary hydroxyproline level. The lower the bone mineralization (Ca/hydroxyproline ratio in biopsy), the higher the retention value. We conclude that the PPi retention is an index of bone metabolism when GFR is higher than 50 ml/min. It allows for classification of metabolic bone diseases according to the bone turnover rate. It has the advantage over the usual biologic examinations in that it affords better observation of highly localized bone disorders and can be used in combination with a morphologic record, the bone scintigraphy.
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  • 10
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    Calcified tissue international 35 (1983), S. 148-152 
    ISSN: 1432-0827
    Keywords: Bone ; Computed tomography ; Densitometry ; Osteoporosis ; Osteomalacia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The linear attenuation coefficient (μ in cm1) of trabecular bone was modeled for different conditions of bone and marrow composition in order to assess their influence on computed tomography (CT) quantitation. A large relative change (10% of TBV at 15% TBV) of bone concentration resulted in small changes of μ: 2.3% at 60 keV, 3.4% at 44 keV, 5.2% at 29 keV. Relative changes of trabecular bone volume (TBV) on the order of 3% could be detectedin vivo by CT were it not for errors of relocation and for compositional influences on accuracy. The μ (and density) depended critically not only on amounts of bone substance and marrow but on their compositions. Normal variation in the composition of bone substance produced an uncertainty in μ equivalent to 0.5 to 1% TBV. Increases of yellow marrow produced a decrease of μ which could be mistaken for a decrease of bone concentration. The biological variation (90% confidence limit) of marrow composition gives an uncertainty at 15% TBV of about 2.4% TBV at 60 keV, 1.7% at 44 keV, and 1.3% at 29 keV. These correspond to relative uncertainities of 16, 11, and 9% respectively. These factors help explain the large accuracy errors (30%) observed in all studies of trabecular bone where single-energy CT was used. Marrow composition also can affect precision of bone measurement. Systematic shifts of red and yellow marrow could mask biological changes such as those occurring with aging or treatment.
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  • 11
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    Calcified tissue international 35 (1983), S. 410-417 
    ISSN: 1432-0827
    Keywords: Bone remodeling ; Histomorphometry ; Corticosteroid therapy ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary We have compared the mean wall thickness (MWT) and active formation periods (sigmaf(A)) of trabecular bone packets in iliac crest biopsies from 20 patients (7 male, 13 female) with corticosteroid-induced osteoporosis (CS-OP) and 20 age- and sex-matched controls. The trabecular bone volume (TBV) of the CS-OP patients (9.6%±2.2% [SD]) was significantly reduced compared to controls (19.3%±5.1%). The MWT of CS-OP patients (32.7±4.3 µm) was also significantly lower than the control value (48.0±6.2 µm). There was a positive correlation between MWT and TBV in both groups. The mineralization rate (M) of the CS-OP patients (0.54±0.25 µm/day) was within the normal range, and since there was no increase in osteoid seam thickness, so therefore was the osteoblastic appositional rate (OAR). The active formation period of trabecular bone packets (sigmaf(A)=MWT/M) was significantly lower in the CS-OP patients (55.9 ± 14.4 days) than in the control group (68.1 ± 9.4 days). MWT and sigmaf(A) both decreased with age in the control group, whereas in the CS-OP group they were independent of age. We conclude that corticosteroid therapy results in a reduction of the MWT of trabecular bone packets and, consequently, of TBV. In these patients, where the OAR was normal, the reduction in MWT was apparently caused by a shortening of the lifespan of the active osteoblastic population at the basic multicellular unit (BMU) level.
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  • 12
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    Calcified tissue international 35 (1983), S. 5-8 
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Quantitative bone histology ; Bone metabolism ; Developmental bone disease ; Growth disorder
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A previously healthy 12-year-old boy developed pain on walking and x-rays showed osteoporosis. Over the next 2 years deterioration occurred, the condition became extremely severe, and he was confined to a wheelchair. After 5 years, marked kyphoscoliosis and pigeon chest deformity were present and little increase in height occurred. A wheelchair accident at the age of 17 resulted in several major long bone fractures. Iliac crest biopsies were taken at ages 15 and 17, and subjected to quantitative histology. A histochemical technique for osteoclast recognition by acid phosphatase activity showed resorption parameters to be normal. Double tetracycline labeling and histochemical identification of osteoblasts showed no abnormality of endosteal bone formation. Because of “coupling” of endosteal formation and resorption, these measurements might primarily reflect bone turnover. Failure of periosteal bone formation as shown by failure of radial growth of long bones and of epiphyseal growth was clearly evident. It is likely that osteoporosis developed in this patient due to a reduction in bone formation of unknown etiology rather than by increased bone resorption.
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  • 13
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    Calcified tissue international 35 (1983), S. 392-393 
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Infrared ; Bone mineral ; Bone resorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary An infrared and x-ray diffraction study of osteoporotic and normal, archaeological Eskimo bones. Osteoporotic bone apatite is greater in crystal size and/or perfection and lower in CO3 than normal bone apatite.
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  • 14
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    Calcified tissue international 35 (1983), S. 29-31 
    ISSN: 1432-0827
    Keywords: Mast cells ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Because mast cell proliferation has been reported in disorders of abnormal bone remodeling, we quantitated the number of mast cells in undecalcified section of iliac crest bone from 16 untreated women with postmenopausal osteoporosis and contrasted the findings to values from 10 normal women and 12 normal men. The mean number of marrow mast cells was greater in normal women than men (1.17 vs 0.40 cells per mm2,P〈0.05). Compared to the normal women, osteoporotic women had a greater number of mast cells in the marrow (3.38 vs 1.17 cells per mm2,P〈0.01). However, there was no statistically significant correlation between the number of marrow mast cells and either the patient's age or the severity of the bone lesions, as assessed by histomorphometry. Our findings confirm the association between increased numbers of mast cells and postmenopausal osteoporosis.
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  • 15
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    Calcified tissue international 35 (1983), S. 107-110 
    ISSN: 1432-0827
    Keywords: Calcium ; Glucocorticoid ; Vitamin D ; Osteoporosis ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Eighty-eight adult male Sprague-Dawley rats were given a diet with either (a) 0.5% Ca and 0.6% P or (b) 0.01% Ca and 0.6% P. Osteopenia was created by adding prednisolone to the diet. The prophylactic effect of oral 1,25(OH)2D3 on the osteopenia was studied. It was found that prednisolone osteopenia in the rat was associated with defective Ca absorption. By giving an oral dose of 1,25(OH)2D3, it was possible to maintain normal Ca absorption during prednisolone treatment and to prevent the bone loss. No significant hypercalcemia or any kidney calcifications were seen. These results are in contrast to earlier findings, in which subcutaneous administration of 1,25(OH)2D3 failed to prevent prednisolone osteopenia because of its tendency to increase bone resorption.
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  • 16
    ISSN: 1432-0827
    Keywords: Bone resonant frequency ; Osteoporosis ; Osteomalacia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A new computerized apparatus was constructed to measure the resonant frequency of human ulnain vivo with high sensitivity and reproducibility. Experimental studies using aluminum bar and dried human bone revealed the importance of the ulna being positioned parallel to the radius, approximately 90 degree flexion of the elbow joint, and minimal muscle activity in order to demonstrate maximum resonant frequency of ulna. Measurement of bone resonance in monkeysin vivo and after removal of the bonein vitro showed good agreement. Product of F (maximum resonant frequency in Hz) and L (ulnar length in cm), FL, indicating the speed of propagation of sound wave through the ulna, showed a significant positive correlation with bone mineral content/bone width (BM/BW) measured by Norland-Cameron apparatus and age-bound decline in both sexes. Patients with osteomalacia and primary hyperparathyroid bone disease tended to have higher FL values than expected from BM/BW. Two-dimensional display of FL and BM/BW thus appears to be useful in distinguishing osteoporosis from osteomalacia better than the use of BM/BW alone.
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  • 17
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Histomorphometry ; Microradiography ; Osteodensitometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Quantitative histomorphometric and microradiographic analysis of iliac crest bone biopsy specimens of 10 unselected and untreated postmenopausal women with osteoporosis was performed and the results were correlated with the values measured by osteodensitometry on the right forearm. No positive correlation between histomorphometry or microradiography and osteodensitometry was observed. Moreover, the data of various histomorphometric parameters and those of the bone mineral content measured by microradiography revealed a significant negative correlation when compared to the values obtained by osteodensitometry. Our results suggest, that evaluation of one skeletal site is not necessarily representative of the entire skeleton in patients with postmenopausal osteoporosis.
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  • 18
    ISSN: 1432-0827
    Keywords: Photon absorptiometry ; Cortical bone density ; Bone index ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary An improved version of a previously described photon absorptiometry method for measuring the bone mineral content of the femoral shaft is presented. The study included 267 healthy persons, who served as control subjects, and 31 osteoporotic and 3 osteomalacic female patients. A monoenergetic source of241Am was used and a fully automatic apparatus designed. The examinations were recorded with an independent microcomputer and secondarily processed by the nuclear unit central computer. The guidelines of Cameron and West were used to perform various calculations from the initial absorption curve, and the clinical usefulness of these was tested. On the one hand, cortical bone density (CBD) and bone linear attenuation coefficient (BLAC) were found adequately to differentiate between osteoporotics and controls, but we defined a discriminative function (F) which allowed even better separation between the two groups. On the other hand, bone index (BI) was found to be the best parameter to follow an individual patient during therapy. These results underline the usefulness of these calculations for detecting and monitoring the progress of pathological states.
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  • 19
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    Calcified tissue international 34 (1982), S. 547-552 
    ISSN: 1432-0827
    Keywords: Rats ; Osteoporosis ; Anorganic ; Femur ; Castrate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The study describes the SEM appearances of endosteal and periosteal surfaces of anorganic femoral diaphyses from 16-month-old normal and castrate male rats. Different types of surfaces could be recognized in both groups. Percentage areas occupied by each surface type were analyzed with a Ladd Data Analyzing Digitizer. Endosteal surfaces were composed of significantly more (P〈0.05) incompletely mineralized, forming surface and significantly less (P〈0.05) completely mineralized, resting surface in castrates than in controls. Both endosteal and periosteal surfaces from experimental bone demonstrated significantly more (P〈0.05) osteoblast lucunae than did control surfaces, and vascular canal entrances were significantly wider (P〈0.001) on castrate endosteal surfaces than on control endosteal surfaces. There was a greater proportion of small nodule forming surface/large nodule forming surface in castrate endosteal bone than in control, and a greater proportion prolonged resting surface/fibrous resting surface in control periosteal bone than in castrate. The results indicate that, when viewed in the SEM, anorganic endosteal and periosteal bone surfaces from femoral diaphyses of old castrate male rats demonstrate appearances characteristic of changes in bone turnover that occur with osteoporosis.
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  • 20
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    Calcified tissue international 34 (1982), S. 519-522 
    ISSN: 1432-0827
    Keywords: Turner's syndrome ; Ovarian dysgenesis ; Osteoporosis ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The bone mineral status of 17 girls with Turner's syndrome was evaluated by single photon absorptiometry. Bone mineral content (BMC) was 25.4% below that predicted by normalization for age, sex, height, weight, and bone width. Only 25% of this demineralization could be attributed to delayed skeletal maturation. Bones of girls who received estrogen replacement therapy were less demineralized than those of the others. The bone mineral deficit became less pronounced with advancing age. It could not be determined if the apparent effect of estrogens was related to age or if the apparent improvement with age was really due to an effect of estrogen treatment. For 8 subjects followed longitudinally there was no significant change in the BMC deficit.
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  • 21
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    Calcified tissue international 34 (1982), S. 510-514 
    ISSN: 1432-0827
    Keywords: Rats ; Osteopenia of oophorectomy ; 1,25-Dihydroxyvitamin D3 ; Parathyroid hormone ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The effect of ovarian insufficiency on calcium metabolism has been thought to involve an increased bone resorptive effect of parathyroid hormone and possible impaired synthesis of 1,25-dihydroxyvitamin D3. In the present study a rat model allowing for controlled serum levels of parathyroid hormone and 1,25-dihydroxyvitamin D3 was used. Oophorectomy in this species is associated with increased serum levels of 1,25-dihydroxyvitamin D3 and decreased bone mass. Although thyroparathyroidectomy increased bone mass, an increased sensitivity of bone to parathyroid hormone in oophorectomized rats was not observed. Thus the development of the osteopenia did not seem to be related to increased parathyroid hormone sensitivity or to reduced levels of 1,25-dihydroxyvitamin D3. Exogenous 1,25-dihydroxyvitamin D3 increased bone mass in oophorectomized as well as intact rats. Intestinal calcium transport was increased by moderate doses of 1,25-dihydroxyvitamin D3. Intestinal calcium transport was also reduced by thyroparathyroidectomy and increased by the administration of parathyroid extract. A tendency for increased accumulation of 1,25-dihydroxyvitamin D3 in blood in oophorectomized rats has been noted. It is suggested that the tendency to hypercalcemia in ovarian-insufficient females given 1-hydroxylated vitamin D compounds may be related to a diminished metabolism of 1,25-dihydroxyvitamin D3.
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  • 22
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Immobilization ; Rats ; Vitamin D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The therapeutic effects of vitamin D analogs, 1,24(R)-dihydroxycholecalciferol [1,24(R)(OH)2D3], 1,24(S)-dihydroxycholecalciferol [1,24(S)(OH)2D3], and 1,25-dihydroxycholecalciferol [1,25(OH)2D3] on immobilization osteoporosis were studied in rats. The right hind limb was immobilized through application of a plaster cast following the section of the sciatic nerve. The left hind limb was intact. Vitamin D analogs were orally administered for 6 weeks at dose levels of 0.02 and 0.10µg/kg/day, respectively. The mean lengths of the immobilized femurs were not significantly different from those of the intact femurs in all the experimental groups. In the immobilized femur of animals treated with 1,24(R)(OH)2D3, 0.10µg/kg, dry and ash weights were heavier and calcium and phosphorus contents greater than those in the nontreated group. Furthermore, the amount of calcified bone mass and the cortical thickness of the femurs of the immobilized limb in 1,24(R)(OH)2D3-treated animals were greater than those in the nontreated animals. Treatment with 1,25(OH)2D3 at 0.10µg/kg caused an increase of the bone mass in both immobilized and intact femurs when compared with those of the control group. It was concluded that the administration of 1,24(R)(OH)2D3 diminished the effect of immobilization in the development of osteoporosis without any side effects.
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  • 23
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    Calcified tissue international 33 (1981), S. 455-457 
    ISSN: 1432-0827
    Keywords: Bone ; Osteoporosis ; Diabetes mellitus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The bone mineral status of fifty-one children with diabetes mellitus was studied by single photon absorptiometry. The mean bone mineral content was 13% below values predicted by age, sex, height, and weight. Those children whose diabetes was one year or less in duration were as osteopenic as those whose diabetes was of longer duration. The demineralized children received a higher daily insulin dose than the others. No association was noted between the degree of skeletal demineralization and sex, statural growth, renal function, and serum calcium and phosphorus. No significant changes in bone mineral content were noted longitudinally.
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  • 24
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    Calcified tissue international 33 (1981), S. 365-368 
    ISSN: 1432-0827
    Keywords: Absorptiometry ; Osteoporosis ; Spinal bone ; Bone mineral content ; Neutron activation ; Calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Dual-photon absorptiometry using153Gd (44 and 100 keV) was used to measure the bone mineral content (BMC) of the trunk and of the total body (TBBM) in 7 volunteers with no overt bone disease. These values were compared to those obtained with partial-body neutron activation of calcium (trunk Ca). The trunk Ca seemed to represent best a 60 × 30 cm area; the correlation coefficient with the corresponding BMC in that area was 0.97 (SEE ⋍ 7%). Trunk Ca was also highly correlated with TBBM (r=0.96; SEE=8%) and with radius BMC (r=0.92; SEE=11%), but the correlations with the BMC of smaller subareas of the trunk were lower (r⋍0.9; SEE ∼ 12%). The BMC of the lumbar spine was only moderately correlated with trunk Ca, radius BMC and TBBM (r ∼ 0.82; SEE ∼ 18%), and only slightly more associated with trunk BMC (r ∼ 0.88; SEE ∼ 14%). The BMC of the combined lumbar-thoracic spine showed higher correlations with trunk Ca, radius BMC and TBBM (r ∼ 0.87; SEE ∼ 13%), and trunk BMC (r=0.93; SEE ∼ 10%). An accurate and sensitive measure of spinal status requires a direct measurement of that area.
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  • 25
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    Calcified tissue international 33 (1981), S. 199-204 
    ISSN: 1432-0827
    Keywords: Bone remodeling ; Histomorphometry ; Trabecular bone ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The mean wall thickness (MWT) and duration of formation periods (sigmaf) of trabecular bone packets have been measured in iliac crest biopsies following double tetracycline labeling from 9 women having primary osteoporosis, with vertebral crush fractures and reduced trabecular bone volume (TBV), and 9 age- and sex-matched controls. The MWT of the osteoporotic biopsies was significantly less than that of the controls and was negatively correlated with age in the latter. There was also a positive correlation between MWT and TBV in the controls but not in the osteoporotics. Sigmaf, in days, showed a tendency to decline with age in the control biopsies and was further decreased in the osteoporotic patients. These results suggest that a major contribution to the negative skeletal balance existing in both primary osteoporosis and physiological osteopenia is a decrease in bone formation, caused by a reduction in the life span of the osteoblastic population at the basic multicellular unit (BMU) level.
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  • 26
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    Calcified tissue international 33 (1981), S. 575-581 
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Vitamin D ; Bone mineral ; Estrogen ; Aging ; Thiazide ; Fluoride ; Calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Bone mineral content (BMC) was measured by125I photon absorptiometry every 3 months in 264 normal females (45–54 years) over a 2-year period together with serum samples for calcium, phosphate, magnesium, creatinine, alkaline phosphatases, potassium, and protein. A 48-h urinary calcium and creatinine measurement was obtained. The subjects were divided into 7 treatment groups and 3 placebo groups. Five of the treatments (thiazide, vitamin D3, fluoride + vitamin D3, fluoride, and 1αD3) were ineffective at the doses used; the annual loss of compact bone was 1.5–2.2% (-X=1.8%), similar to the loss seen with placebos. Estrogen and estrogen + thiazide, in contrast, produced a 1.34% annual increase of BMC. The subjects were divided into groups with low, medium, and high initial BMC. Also, individual regressions for bone change were calculated and the subjects were divided into groups of responders, maintainers, and losers (annual change of 〉0%, 0 to −1%, and 〉−1%, respectively). The initial BMC status did not consistently affect bone or biochemical responses to the therapeutic agents. Estrogen was effective even in subjects with high BMC, whereas the other agents did not inhibit bone loss even in subjects with low initial BMC. Virtually all subjects responded to estrogen positively; in contrast we could not identify a subset of “responders” with any of the other treatments. Time since menopause appeared to influence the bone changes, although it was not a significant effect given the sample size. Bone loss in groups not treated with estrogens was 2%/year at 20 months after menopause with a decline to 1.3%/year at 45 months post-menopause. There was no apparent decline in the bone response to estrogen during the first 4 years after menopause, and in fact bone response tended to increase with time.
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  • 27
    ISSN: 1432-0827
    Keywords: Paraplegia ; Bone mineral ; Bone blood flow ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The mechanism of bone loss after a spinal cord section with paraplegia is still largely unknown. The purpose of this study was to investigate in paraplegic rats the rate and distribution of bone loss, changes in bone calcium metabolism, and bone blood flow. Female Sprague-Dawley rats aged 100–120 days were rendered paraplegic by sectioning the spinal cord at the 11th dorsal vertebra. By comparison with their sham-operated controls (SO controls), we found a diminished bone calcium content in the tibia and femur (paralyzed region) and in the humerus (supralesional region) of the paraplegic animals. In the femur bone calcium loss was present within a week and at 12 weeks had reached 22%; in the tibia it started at about 2 weeks and at 12 weeks had reached 15%; in the humerus it started at about 5 weeks and reached 7.5%. It was not uniform and was greatest in the metaphyseal-epiphyseal regions on either side of the femorotibial joint. The blood flow in femur and tibia was measured by the technique of arteriolar blockade of 15 µm microspheres. It was continuously higher in the paraplegic animals than in the SO controls, from 1 to 12 weeks. In both groups, paraplegics and controls, the bone blood flow was unequally distributed in the two bones; it was greatest in the same metaphyseal-epiphyseal regions contiguous to the femorotibial joint. The 72 h45Ca clearance by the femur and tibia was lower in the paraplegic animals, indicating that bone deposition had slowed down and perhaps that resorption had occurred. The fact that the site of maximum bone calcium loss and the site where the blood flow was greatest are the same suggests a close relationship between the increased blood flow and demineralization, whether it be causal or not.
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  • 28
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    Calcified tissue international 32 (1980), S. 77-82 
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Castration ; Density ; Femur ; Rats
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Forty young (23-day-old) and thirty old (1-year-old) male rats were castrated and sacrificed with controls at intervals up to 18 months of age. No differences were observed between femurs or mandibles of rats castrated at 23 days and those of controls. Year-old castrate rats developed femoral osteoporosis after 2 months, which became more pronounced 4 months after castration. This was characterized by reductions in femoral density, dry weight, dry weight per unit length, and ash weight, and by the appearance of resorption cavities in diaphyseal walls and a sparsity of trabeculae in metaphyses and epiphyses of castrate femurs. These results indicate that the year-old castrate male rat may be a valuable experimental model for studies of the treatment of osteoporosis.
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  • 29
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    Calcified tissue international 4 (1969), S. 94-100 
    ISSN: 1432-0827
    Keywords: Acid ; Base equilibrium ; Acidosis ; Bone ; Resorption ; Metabolism ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'administration chronique de chlorure d ammonium à des rats adultes normaux, soumis à un régime contenant un taux approprié de vitamine D, provoque une ostéoporose. Celle-ci est provoquée par une perte de substance d'os et de minéral osseux, associée à l'augmentation de la résorption osseuse.
    Abstract: Zusammenfassung Chronische Verabreichung von Ammoniumchlorid an normale ausgewachsene männliche Ratten, die eine entsprechende Vitamin-D-haltige Diät erhalten, verursacht die Entwicklung einer Osteoporose. Die Osteoporose entsteht auf Grund eines Verlustes von Knochensubstanz und Knochenmineral, in Begleitung einer erhöhten Knochenresorption.
    Notes: Abstract Excessive administration of ammonium chloride to normal adult male rats receiving a diet adequate in vitamin D caused the development of osteoporosis. The osteoporosis was due to loss of bone substance and bone mineral associated with increased bone resorption.
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    Calcified tissue international 4 (1969), S. 185-187 
    ISSN: 1432-0827
    Keywords: Cartilage ; Trauma ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La masse du mineral osseux du bout distal femoral a été mesuré dans 54 cas de rupture du cartilage semilunair médial 0–5 années après l'intervention chirurgique. La masse du mineral osseux était diminué. La masse du mineral osseux n'avait aucune tendance de restauration pendant le temps d'observation.
    Abstract: Zusammenfassung In 54 Fällen von medialen Meniscusschäden wurde die Skeletmasse in dem distalen Femurende gemessen 0–5 Jahre nach der Fortnehmung des geschädigten Meniscus. Die Skeletmasse war signifikant vermindert. Im Laufe der Zeit zeigte sich keine Tendenz zur Erhöhung der Skeletmasse.
    Notes: Abstract In 54 cases of ruptured medial semilunar cartilages of the knee joint the bone mineral mass in the distal end of the femur was measured 0–5 years following removal of the injured cartilage. The bone mineral mass was significantly decreased. There was no tendency of restoration of the bone mass with time.
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  • 31
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    Calcified tissue international 4 (1969), S. 245-256 
    ISSN: 1432-0827
    Keywords: Bone ; Densitometry ; X-ray ; Diet ; Calcium ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'ingestion quotidienne de calcium of été déterminée en interrogeant 398 individus, âgés de 15 à 90 ans. Le rapport entre l'ingestion de calcium et la minéralisation vertébrale, mesurée par densitométrie radiographique quantitative, est fiable mais cependant significatif. Chez 53 personnes, atteintes d'ostéoporose, comparées à un nombre égal d'individus, d'âges similaires, les valeurs de la minéralisation vertébrale sont 60 pour cent plus faibles que celles du groupe témoin. L'ingestion totale moyenne de calcium est plus faible de 21 per cent chez les ostéoporotiques. Chez les sujets, à ingestion unique de calcium, les patients du groupe témoin ingèrent preque le double de calcium que le groupe des ostéoporotiques. Une diminution moyenne de l'ingestion calcique est notée avec l'âge. Il semble qu'il existe une diminution de l'absorption calcique avec l'âge, l'ostéoporose ou les deux, ainsi qu'un besoin plus grand en calcium chez les sujets âgés pour assurer l'équilibre en calcium. Indépendamment de l'homéostase calcique, un équilibre négatif en calcium augmente la résorption osseuse, et diminue l'ostéogenèse. De nombreux facteurs interviennent dans l'étiologie et la pathogénie de l'ostéoporose: les résultats de cette étude indique que la présence de calcium alimentaire est l'un de ces facteurs.
    Abstract: Zusammenfassung Die tägliche Calciumeinnahme wurde anhand einer Befragung von 398 Personen im Alter von 15–90 Jahren geschätzt. Die Korrelation der Calciumeinnahme und der Mineralisation der Wirbelsäule, wie sie röntgenologisch durch quantitative Messung der Dichte festgestellt wurde, war niedrig, aber durchwegs signifikant. Bei 53 Osteoporose-Patienten, die mit 53 Kontrollpersonen gleichen Alters verglichen wurden, waren die Mineralisationswerte der Wirbelsäule um 60% niedriger als jene der Kontrollgruppe, und die durchschnittlich geschätzte Gesamt-Calciumeinnahme der Osteoporotiker war um 21% tiefer. Von den Exploranden, die Angaben über eine gleichmäßige Calciumaufnahme machten, nahmen die Kontrollpersonen beinahe doppelt so viel Calcium ein als diejenigen mit Osteoporose. Im Durchschnitt wurde eine Verminderung der Calciumeinnahme mit fortschreitendem Alter festgestellt. Es ergibt sich deutlich, daß die Calciumabsorption mit dem Alter, bei Osteoporose oder in der Kombination dieser beiden Faktoren abnimmt, und daß eine größere Calciumeinnahme bei älteren Personen nötig wäre, um eine positive Calciumbilanz aufrechtzuerhalten. Ungeachtet der Komplexität der Calciumhomöostase, kann eine negative Calciumbilanz schließlich dazu führen, daß mehr Knochen resorbiert als gebildet wird. Demzufolge sollte bei erkanntem Bedürfnis eine adäquate Calciumeinnahme gesichert sein. Es ist eine Tatsache, daß viele Faktoren an der Ätiologie und Pathogenese der Osteoporose beteiligt sind; die Resultate dieses Berichtes unterstützen die Wahrscheinlichkeit, daß das Calciumangebot in der Nahrung einer dieser Faktoren ist.
    Notes: Abstract Lifetime daily calcium intake was estimated through interview of 398 individuals from 15 to 90 years of age. The correlation of calcium intake with vertebral mineralization as determined by quantitative radiographic densitometry was low but persistently significant. In 53 persons with osteoporosis matched by age with 53 individuals from the control group, vertebral mineralization values were 60% lower than those of the control group, and the mean estimated total calcium intake in osteoporotics was 21% lower. In those persons reporting a single lifetime calcium intake, the control patients ingested almost twice as much calcium as those with osteoporosis. A mean decrease in calcium intake with advancing years has been shown. Evidence points to a decrease in calcium absorption with age, osteoporosis, or both, as well as a greater need for calcium intake in the elderly to maintain a positive calcium balance. Regardless of the intricacies of calcium homeostasis, a negative calcium balance leads eventually to greater bone resorption than formation, hence the rationality of insuring an adequate calcium intake with recognized nutritional needs. Evidence suggests that many factors are involved in the etiology and pathogenesis of osteoporosis; the data in this report support the likelihood that availability of calcium in the diet is one of them.
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    Calcified tissue international 4 (1969), S. 147-161 
    ISSN: 1432-0827
    Keywords: Cancellous bone ; Trabeculae ; Osteoporosis ; Remodelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une étude de l'épaisseur et de l'espacement des structures osseuses dans l'os d'aspect réticulé du crête iliaque. Les specimens provenant de 67 sujets normaux, ages de 20 à 90 ans, furent enfoncés dans methacrylate et tranches preparés par meulage. L'age croissant est accompagné d'une augmentation de l'espacement entre les structures osseuses, mais pas d'une reduction signifiante de leur épaisseur. Les structures osseuses les plus minces paraissent subir le plus grand remondellage, jugant par l'importance de surfaces de formation et de résorption.
    Abstract: Zusammenfassung Die Dicke der Trabekel und die Weite der Markzwischenräume des Hüftbeinkammes wurden bestimmt. Das in Methacrylat eingebettete Material, welches von 67 Normalpersonen im Alter von 20–90 Jahren stammte, wurde geschnitten und untersucht. Bei zunehmendem Alter vergrößert sich der Raum zwischen den Trabekeln, ohne daß jedoch deren Dicke signifikant vermindert wird. Gemessen am Umfang der Bildungs- und Resorptionsoberfläche scheinen die dünnsten Trabekel dem größten Knochenumbau unterworfen zu sein.
    Notes: Abstract A study of the thickness and spacing of bony structures in the cancellous bone of the iliac crest. Ground sections of methacrylate-embedded material from 67 normal subjects, from 20 to 90 years of age, were examined. Increasing age is accompanied by an increase in the spacing between the bony structures, but not by any significant reduction in their thickness. The thinnest bony structures appear to be undergoing the most remodelling, as judged by the extent of formation and resorption surfaces.
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  • 33
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    Calcified tissue international 2 (1968), S. 20-29 
    ISSN: 1432-0827
    Keywords: Bone Atrophy ; Bone Resorption ; Calcium ; Collagen ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Atrophie osseuse d'immobilisation était induite par section de la plexus brachial et/ou désarticulation de la coude. Après 9 bis 12 semaines de désuétude huméri intactes furent examinés par rayons X et leur qualités physiques déterminés. Les humérientiers furent isolés, dégraissés, desséchés au poids constant, et leur teneur en cendre d'os et collagène déterminés. Huit des 10 huméri immobilisés monstrérent radiodensité diminué. La jambe inusitée monstra perte parallèle en poids sec et poids sans gras (−23.2%), en collagène (−25.3%), et en cendre d'os (−26.1%) en comparaison de la jambe normale. Les données monstrèrent que la portion plus grande du tissu osseux perdu en atrophie osseuse d'immobilisation est remplacée par de l'eau, du gras, et des autres matériels organiques inconnus plutôt que par tissu fibreux, et que collagène est perdu en proportion du minéral. La perte proportionellement plus grande du collagène et de la cendre d'os que du poids sec et poids san gras semble dû à une augmentation du matériel organique, non-collagéne, non-lipide, kprobablement protéine.
    Abstract: Zusammenfassung Immobilisations-Knochenatrophie wurde in 10 erwachsenen Hunden herbeigeführt durch Brachialplexusschnitt und/oder Ellenbogenexartikulation. Nach 9–12 Wochen der Immobilisation wurden die intakten Humeri unter Röntgenstrahlen untersucht und ihre physischen Eigenschaften bestimmt. Derintakte Humerus wurde isoliert, entfettet, zu konstantem Gewicht getrocknet und der Knochenaschengehalt und Kollagengehalt bestimmt. Acht der 10 experimentellen (immobilisierten) Humeri demonstrierte Beweis von verringerter Röntgendichte. Die immobilisierte Extremität zeigte ähnlichen Verlust in trockenem, fettfreiem Gewicht (−23,2%) in Kollagen (−25.3%) und Knochenasche (−26,1%) im Vergleich zur normalen Extremität. Die Date deuten an, daß der Hauptanteil des Verlustes des Knochengewebes (bei Immobilisations-Knochenatrophie) von Wasser, Fett und anderen unidentifizierten organischen Substanzen ersetzt wird, als von Faserngewebe und daß Kollagen und Knochenasche im gleichen Verhältnis verloren gehen. Der größere, proportionale Verlust an Kollagen und Knochenasche, eher als der Verlust an fettfreiem Gewicht, scheint in der Zunahme an nicht kollagener, nicht lipoider, organischer Substanz, vermutlich Protein, zu liegen.
    Notes: Abstract Disuse bone atrophy was induced in 10 adult dogs by means of brachial plexus section and/or elbow disarticulation. After 9 to 12 weeks of disuse intact humeri were examined by X-ray, and their physical properties determined. Thewhole humeri were isolated, defatted, dried to constant weight, and their mineral and collagen content determined. Eight out of 10 experimental (non-used) humeri demonstrated evidence of decreased radiodensity. The non-used limb demonstrated parallel loss in dry, fat-free weight (−23.2%), in collagen (−25.3%), and in mineral (−26.1%), as compared to the normal limb. The data indicated that the major portion of the lost bone tissue in disuse osteoporosis is replaced by water, fat, and other unidentified organic materials rather than fibrous tissue, and that collagen is lost in equal proportion to mineral. The proportionatelly greater loss of collagen and mineral than of dry, fat-free weight appears to be due to an increase of non-collagenous, non-lipid organic material, presumably protein.
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