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W. J. RUSSELL 《Anaesthesia》1983,38(11):1062-1065
In a double-blind controlled trial of male patients undergoing transurethral resection of the prostate, oral lorazepam was assessed against a placebo. The same anaesthetist performed all spinal blocks and made all assessments. The patients who received lorazepam had substantial amnesia for the operation and were drowsier, but remained cooperative during the procedure. Patient anxiety as assessed by the anaesthetist and as recalled by the patient was decreased, although anxiety assessment by linear analogue was the same for both groups. Lorazepam significantly increased the patient acceptability of spinal anaesthesia. 相似文献
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D. F. GUILLARD-CUMMING D. J. BEARD D. L. DOUGLAS S. K. JOHNSON P. J. LAWSON-MATTHEW R. G. G. RUSSELL J. A. KANIS 《Clinical endocrinology》1985,22(4):559-566
We have studied several biochemical indices of bone turnover and vitamin D metabolism in 32 untreated patients with Paget's disease and in 32 age-matched control subjects. patients with Paget's disease, as expected, were characterized by high bone turnover, as judged by alkaline phosphatase and urinary excretion of hydorxyproline. Serum values of 24,25-dihydroxyvitamin D3 (24,25(OH)2D3) and the ratio of 24,25(OH)2D3 to 25-OHD were significantly lower in patients than in control subjects. Serum concentrations of 1,25(OH)2D3 were normal in Paget's disease. The distribution of values for 24,25(OH)2D3 was log normal. On the basis of the normal range computed from control subjects, patients were divided into those with low or normal values for 24,25(OH)2D3. Disease activity, as judged by biochemical indices was significantly higher in the patients with the lower values of 24,25(OH)2D3. We conclude that Paget's disease is characterized by low circulating concentrations of 24,25(OH)2D3, particularly in patients with more extensive or severe disease. 相似文献
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Spermiogenesis and spermiation in a monotreme mammal, the platypus, Ornithorhynchus anatinus 总被引:1,自引:0,他引:1
Spermatogenesis in the platypus ( Ornithorhynchus anatinus ) is of considerable biological interest as the structure of its gametes more closely resemble that of reptiles and birds than marsupial or eutherian mammals. The ultrastructure of 16 steps of spermatid development is described and provides a basis for determining the kinetics of spermatogenesis. Steps 1–3 correspond to the Golgi phase of spermatid development, steps 4–8 correspond to the cap phase, steps 9–12 are the acrosomal phase, and steps 13–16 are the maturation phase. Acrosomal development follows the reptilian model and no acrosomal granule is formed. Most other features of spermiogenesis are similar to processes in reptiles and birds. However, some are unique to mammals. For example, a thin, lateral margin of the acrosome of platypus sperm expands over the nucleus as in other mammals, and more than in reptiles and birds. Also, a tubulobulbar complex develops around the spermatid head, a feature which appears to be unique to mammals. Further, during spermiation the residual body is released from the caudal end of the nucleus of platypus sperm leaving a cytoplasmic droplet located at the proximal end of the middle piece as in marsupial and eutherian mammals. Other features of spermiogenesis in platypus appear to be unique to monotremes. For example, nuclear condensation involves the formation of a layer of chromatin granules under the nucleolemma, and development of the fibrous sheath of the principal piece starts much later in the platypus than in birds or eutherian mammals. 相似文献
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