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141.
Reabsorptive action of collagen fibers of the liver   总被引:35,自引:0,他引:35  
  相似文献   
142.
Twenty-one patients, under 6 years of age, with root avulsion of the brachial plexus were treated from 1975 to 1987. Among them, 9 had root avulsion of the upper trunk, 2 root avulsion of the lower trunk with middle trunk broken, and 10 root avulsion of the whole brachial plexus. Follow-up of 16 patients showed excellent results in 2 patients, good in 11, fair in 1 and poor in 2. It is suggested that good results can be obtained if multi-paired nerve transfer is adopted in treatment. We conclude that owing to anatomical and physiological characteristics of the respiratory system in children, it is harmful to perform phrenic nerve transfer concomitantly with intercostal nerve transfer. Advisably, two-stage operation is required, otherwise dyspnea and pneumonia are liable to occur. In addition, the time of the operation could be extended to 4-5 years after injury in children, but best results are obtained if the operation is performed within 1 year.
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143.
 Within a number of physiological preparations, the effects of alcohol and cocaine in combination are reported to be greater than the effects of either drug given alone. Little has been reported, however, on the behavioral effects of the interaction. The present study investigated this issue by assessing the effects of cocaine and alcohol (alone and in combination) on schedule-controlled responding. Specifically, rats were trained to respond on an FR20 schedule for a water reinforcer. They were then administered cumulative doses of cocaine or alcohol. Following this, subjects were administered ineffective doses of alcohol prior to further dose-response assessments with cocaine and with ineffective doses of cocaine prior to further dose-response assessments with alcohol. Cocaine and alcohol alone produced dose-related decreases in responding. Furthermore, the dose-response function for cocaine was shifted to the left by alcohol and the dose-response function for alcohol was shifted to the left by cocaine. An isobolographic analysis revealed that the interaction between cocaine and alcohol was additive in nature. The possible bases for the interaction (e.g., changes in cocaine pharmacokinetics by alcohol and the formation of cocaethylene following co-administration of cocaine and alcohol) were discussed. Received: 22 February 1996 / Final version: 23 August 1996  相似文献   
144.
目的:研究依那普利(Ena)对豚鼠乳头状肌电生理特性,哇巴因诱发的延迟后除极(DAD)和触发电活动(TA)的直接作用方法与结果,采用标准玻璃微电极技术记录豚鼠乳头状肌动作电位,Ena呈浓度依赖性增加静息膜电位(RP)和动作电位幅度(APA),而对0期最大除极,超射,和动作电位时程无明显影响Ena10μmol.L^-1则可明显抑制哇巴因0.5μmol.L^-1则可明显抑制哇巴因0.5μmol.L^-  相似文献   
145.
本文观察分析了13例特发性甲状旁腺功能低下患者、查PTH6例。患者血清中除有本病低血钙、高血磷的固有特征外,其它微量元素也有改变,如血清镁值减低。这与文献[1]的报道相符。碱性磷酸酶2例明显升高。磷廓清率S例降低。肾小管磷重吸收率5例升高。放免甲功:抗甲状腺微粒体2例升高。T细胞亚群1例低于正常值。本病有家族性,与遗传有关。  相似文献   
146.
147.
There is little agreement about the methodology of clinical trials of antipsychotic drugs in patients with negative symptoms. A literature review revealed wide variation in experimental design, rating scales and study duration. This reflects differing views as to the definition and response to treatment of negative symptoms. Some degree of standardization would improve comparability of studies and aid the development of new compounds. Patients included in such studies should have displayed negative symptoms for at least 6 months. Depressive symptoms, positive schizophrenic symptoms and extrapyramidal signs may all influence or be confused with negative symptoms and may respond to treatment; they should be at a low level at baseline and should be measured during the study period. Studies should last at least 8 weeks. Several scales are available for measuring negative symptoms and are reviewed; a global impression score should be used additionally.  相似文献   
148.
The Authors are reviewing their experience of Obstructive Uropathies diagnosed and treated surgically in neonates, the last 8 years in their Institution. 67 cases were reviewed, in which 37 presented with ureteropelvic junction obstruction (UPJ). 13 with posterior urethral valves, 11 with primary megaureter and 6 with ureterocele. Prenatal ultrasonography allowed the diagnosis to be made in two third of the patients. UPJ is the most common obstructive uropathy observed. Posterior urethral valves the most severe because of high pulmonary and renal (dysplasia) complication rate. Surgery, when indicated, has no more complications to be expected than in general population, if oriented prophylactic measures are taken in the early peri- and postoperative period.  相似文献   
149.
Liver fibrosis was induced in rats by repeated peritoneal injections of carbon tetrachloride (CCl4) over a period of 2-11 weeks. Serum procollagen III peptide (SPIIINP), prolidase (SP) and alanine aminotransferase (SALT) levels were monitored during the period of induction. The extent of fibrosis was semi-quantitatively estimated after collagen staining, and the anti-fibrotic effects of 16,16-dimethyl prostaglandin E2 (DMPGE2), colchicine, and zinc sulphate were studied. SPIIINP and SP were increased the first 2 weeks after CCl4 administration and peaked at 6 weeks. Alterations in SPIIINP and SP correlated well to the semi-quantitative histological score of liver sections during the first 6 weeks, and SP was positively related to SPIIINP throughout the whole induction period. DMPGE2 decreased SPIIINP, SP and SALT significantly in addition to a markedly decreased formation of liver collagens. Colchicine had a similar but less dramatic effect, whereas zinc sulphate only reduced SPIIINP without influencing liver damage. In conclusion SPIIINP seems to be a valuable indicator of liver fibrogenesis, and SP may play a limited role in indicating accelerated collagen metabolism in the liver. DMPGE2 obviously inhibited the production of collagens induced by CCl4. Colchicine also had an apparent effect on liver fibrosis, whereas zinc sulphate merely seemed to postpone it.  相似文献   
150.
常才  朱关珍 《生殖与避孕》1994,14(3):193-197
本研究采用先进的三维超声成像技术及多普勒技术对正常育龄妇女月经周期中心血管功能进行研究。结果:月经周期中HR、BP无变化;血清E2是周期性变化,排卵前达高峰。SV、CO、EF在排卵前期升高达峰值,显著高于月经期和黄体期;SVR排卵前期最低,而Ved、Ves无变化。Vmax、A、E在内源性E2高峰时明显加快,而E/A比值无明显变化。结果提示:月经周期中随内源性E2的周期性变化,心脏功能也发生周期性变化。E2高峰时,心输出量、心搏量和射血分数达最高。外周阻力最低,心脏内血流速度加快。  相似文献   
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