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91.
Bone mineral density in patients with prostatic cancer treated with orchidectomy and with estrogens 总被引:7,自引:0,他引:7
Bone mineral density (BMD) and bone mineral content (BMC) were measured in the femoral neck area, trochanteric area and Wards triangle, and in the distal radius of the left forearm before and after 1 year of endocrine treatment in 27 patients with prostatic cancer. Eleven of the patients were treated with orchidectomy and 16 with combined oral and intramuscular estrogens. The patients were free from metastases during the entire observation period. In the orchidectomized patients, BMD and BMC of the distal radius decreased significantly following treatment, whereas no changes were observed in the estrogen-treated patients. These preliminary results demonstrate that estrogens may protect bone in male subjects also and may merit further investigations on larger groups of patients. 相似文献
92.
Several areas related to the use of telescopes in low vision are reviewed. These include: contrast sensitivity function; eccentric viewing through a telescope; field of view; telescope used in reverse; and IOL-spectacle lens telescopic systems. Experimental data are included to support selected clinical observations routinely made by low vision clinicians. 相似文献
93.
M. S. Levine A. M. Adinolfi R. S. Fisher C. D. Hull D. Guthrie N. A. Buchwald 《Brain research》1988,440(2):267-279
These studies provide information on the changes in the ultrastructure in the caudate nucleus of aged cats. The major findings was that there was a decrease in the density of synapses in caudate neuropil. This decrease occurred in animals after 3 years of age and remained relatively constant in older animals. In conjunction with this change a population of unusually long synapses also occurred. These larger synaptic appositions were associated with enlarged spine heads. The caudate also showed a number of qualitative ultrastructural alterations. Many neurons contained accumulations of lipofuscin or lipopigment granules in aged animals. These inclusions occurred in both soma and dendrites of neurons and all types of glial cells. A unique configuration of collapsed agranular cisterns also was observed in aged animals. The present results indicate that decreases in synaptic density may by one morphological event underlying functional alterations observed in caudate neurons in aged cats. 相似文献
94.
Agents for prevention or treatment of osteoporosis must now be tested in a large animal species that exhibits bone remodeling.
Ovariectomized, nonhuman primates provide one such model, and they consistently develop osteopenia accompanied by high bone
turnover rates. The goal of this study was to further characterize this model, and particularly to determine the effect of
ovariectomy on bone strength in vertebrae and femoral necks. Longitudinal evaluations of spinal bone mass and serum markers
of bone turnover were performed in 19 sham-ovariectomized (SHAM) and 18 ovariectomized (OVX), domestically reared cynomolgus
monkeys, aged >9 years. OVX monkeys lost bone relative to both baseline values and SHAM controls. Serum markers of bone turnover
were increased by OVX. After 72 weeks, both vertebral bone compressive strength and femoral neck breaking strength were significantly
decreased in OVX animals compared with SHAM. Ovariectomized cynomolgus monkeys, like postmenopausal women, develop accelerated
bone loss, increased bone turnover, and reduced bone strength, and provide a suitable large animal model for efficacy studies
with agents for prevention or treatment of osteoporosis.
Received: 24 June 1996 / Accepted: 3 September 1996 相似文献
95.
控制性降压在临床麻醉中的应用进展 总被引:6,自引:0,他引:6
控制性低血压是指在某些手术麻醉期间,用药物等方法降低血压,以达到减少手术野出血,便于手术操作的一种方法,通常采用血管扩张剂,钙通道阻断剂及麻醉来控制血压,现就这一领域的研究进展作一综述。 相似文献
96.
本研究以豚鼠皮层听觉诱发电位反应阈为指标,采用自体或群体对照方法,观察0.1Hz极低频磁场对豚鼠听力的影响。结果表明,豚鼠经50mT(毫特)、4h,100mT、48h及10mT、4周暴露后,听阈降低;50mT、48h,20mT、4周暴露后听阈无明显变化。提示0.1Hz极低频磁场对豚鼠听敏度无不利的影响,在某些暴露条件下,听敏度尚有改善。 相似文献
97.
Purpose: Following the widespread adoption of energy-dependent rare earth intensifying screens this study investigates the relevance of two conventions (the 10 kVp and kVp-to-the-4th-power rules) commonly used to calculate the kVp/mAs relationship.Methods: A stepwedge was exposed at standard kVp and mAs setting. The kVp was then increased in increments of 5 kVp, and appropriate mAs values were determined using a densitometer. These values were then compared with approximations from the rules previously mentioned.Results: Wide discrepancies are reported between appropriate and approximated values with the latter overestimating exposure by a factor of two.Discussion: Traditional theorems used to estimate the kVp/mAs relationship should no longer be used in modern imaging departments. Each film screen combination should be evaluated individually to ensure appropriate exposure settings. 相似文献
98.
长跑运动对老年人尺桡骨密度影响的观察 总被引:1,自引:1,他引:0
本文对63名老年长跑运动员及非运动老年人的尺桡骨骨密度进行了测定。结果表明,男性运动组尺、桡骨骨密度及风桡骨骨密度均值比非运动组显著升高,男性运动年限>10年组桡骨骨密度、尺桡骨骨密度均值明显高于运动年限≤10年组,而女性运动组尺桡骨骨密度及尺桡骨骨密度均值与非运动组相比无明显差异。提示,坚持长跑锻炼在预防老年性骨质疏松症中,对男性作用明显,而对女性作用不显著。 相似文献
99.
用统计学方法对14年来(1977~1990年)我校6746名新生(13492只眼)的视力状况进行分析。结果表明;新生正常视力逐年减少,视力不良率相应上升(P<0.001)。城市学生的视力比农村学生差,男生的视力优于女生(P<0.001)。17~19岁组的视力明显低于其他年龄组(P<0.001)。高考分数线升高与正常视力者减少呈明显负相关;而与视力不良者增加呈正相关(P<0.001,<0.05)。本文认为近距离用眼持续时间过长及环境视域小等是引起视力不良的主要原因。 相似文献
100.
H. H. LUTTROPP R. THOMASSON S. DAHM J. PERSSON O. WERNER 《Acta anaesthesiologica Scandinavica》1994,38(2):121-125
Xenon is a more potent anesthetic than nitrous oxide, and gives more profound analgesia. This investigation was performed to assess the potential of xenon for becoming an anesthetic inspite of its high manufacturing cost. Seven ASA I—-II patients undergoing cholecystectomy (n = 4), hernia repair (n = 2), or mammoplasty (n=l) were studied. Denitrogenation by 15–20 min of oxygen breathing under propofol anesthesia was followed by fentanyl–supplemented xenon anesthesia administered via an automatic minimal flow system which held the oxygen concentration at 30%. Xenon anesthesia lasted 76–228 min and 8–14 1 of xenon (ATPD) was used, of which 5.6–8.1 1 was expended during the first 15 min. Anesthesia appeared to be satisfactory, and the patients woke up rapidly after xenon was discontinued. The automatic system made minimal flow xenon anesthesia easy to administer, but nitrogen accumulation is still a problem. Assuming a xenon price of 10 US $ per litre, the average cost for xenon was about 65 US $ for the first 15 min and then about 25 USS for each subsequent hour of anesthesia. 相似文献