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11.
The presence of cytochrome P-45011 beta in rat brain was studied by immunohistochemistry using polyclonal rabbit antibodies raised against purified bovine adrenocortical P-45011 beta, which is involved in the steroid 11 beta-hydroxylation and glucocorticoid formation. The results showed that cytochrome P-45011 beta immunoreactivity is selectively localized to the tracts of myelinated fibers throughout the brain. The specificity of immunohistochemical stainings with P-45011 beta antibodies was established by control tests including nonimmune rabbit immunoglobulin Gs and P-45011 beta antibodies absorbed with purified antigen. Western immunoblots of homogenates from different brain areas with P-45011 beta antibodies, together with biochemical enzymatic assays for cytochrome P-45011 beta monooxygenase activity in these homogenates, confirmed the selective localization of this enzyme observed with immunohistochemistry. Cytochrome P-45011 beta and 11 beta-hydroxylase activity were detected in a homogenate from the cortical white matter (brain area rich in myelinated fibers) as in that from the rat adrenal, but were not detectable in a homogenate from the cerebral cortex (brain area poor in myelinated fibers). Furthermore, quantitation of the P-45011 beta bands on the immunoblots by the areal density revealed that the cortical white matter contains approximately 1.4 pmol of cytochrome P-45011 beta/mg of tissue protein, the value of which was about one sixth of the corresponding value estimated in the rat adrenal. This relatively high content of cytochrome P-45011 beta was also reflected in a relatively high level of 11 beta-hydroxylase activity measured in a homogenate of this brain area by biochemical enzymatic assays using [4-14C]-11-deoxycorticosterone.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
12.
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM.  相似文献   
13.
新疆医科大学为全国第二家中西医合并院校.在新疆进行中西医合校,实属时势所使,事在必行.强弱相合,处于弱势的中医学院只有坚持相对独立,才能保证于合校后发扬中医药特色、办好中医药教育.中西医合校,给原本弱小的新疆高等中医药教育事业的发展带来了诸多可供凭借和利用的积极因素,同时也存在不少负面影响.新疆医科大学在实践中认清了中西医同校的优势与缺憾,采取扶持和爱护中医的策略,不断尝试规避冲突、化解矛盾、趋利祛弊、务期和谐,终喜事业有成,使高等中医药教育得以在新疆生存,并越过低谷,走上健康发展之路.  相似文献   
14.
Coating and doping with zinc have been used to modify LiNi0.5Mn1.5O4 powders prepared at 700 and 800 °C. As previously found in the literature, surface treatment with zinc leads to a net improvement of the electrochemical performance of the 5-V electrode in lithium cells. X-ray diffraction reveals the occurrence of surface ZnO, which disappears after heating at 500 °C. This indicates that ZnO forms a coating, although zinc can also be incorporated in the LiNi0.5Mn1.5O4 framework. The electrochemical oxidation of both bare LiNi0.5Mn1.5O4 and zinc treated products has been followed by ex situ X-ray diffraction of charged electrodes. For both materials a decrease in the cubic unit cell parameter and the formation of two cubic phases during lithium extraction has been found. Lattice contraction is significantly larger in the sample modified with zinc. EIS measurements give direct evidence of the better stabilization of the electrode surface in the coated material.  相似文献   
15.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
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17.
调查了十九世纪汉译西洋医学著作在日本的出版和流传情况,有9种汉译西洋医学著作曾在日本出版,其中6种曾多次再版,7种有和训或和译本,这些著作曾在日本医生中广泛流传,促进了西洋医学在日本的传播和普及,对日本医学从传统医学向现代医学的转变起过一定的作用。本文还分析了汉译西洋医学著作能够在日本广泛流传的原因  相似文献   
18.
目的:探讨数学障碍儿童的工作记忆状况。方法:采用智力测睑、成就测验、教师提名、学业成绩相结合的综合标准甑选数学障碍儿童,在长沙市三所小学随机选取4~6年级共12个班,从中抽取24名数学障碍儿童和24名学习正常儿童。采用工作记忆成套测验对2组被试进行评估。结果:数学障碍组除空间排序、空间后退以及数字划销3个分测验外,在工作记忆成套测验其它各分测验及各维度上的成绩均显著低于学习正常组(P〈0.001~0.05)。结论:数学障碍儿童工作记忆存在普遍缺陷。  相似文献   
19.
为探讨特异性血管紧张素Ⅱ受体 1阻断剂氯沙坦调节高血压血管重塑与细胞外信号调节激酶的关系 ,本文采用两肾一夹型高血压大鼠为动物模型 ,术后第 2、4、6周测血压 ,6周后处死大鼠称心脏重量 ,取胸主动脉和肠系膜动脉作形态学观察和计算机图像分析 ,免疫印迹方法检测主动脉中磷酸化细胞外信号调节激酶及总细胞外信号调节激酶的表达。结果发现 ,与假手术对照组相比 ,模型组大鼠血压和心脏与体重之比分别增加 5 0 %和 48%(P均 <0 .0 1) ,主动脉和肠系膜动脉的内径与中膜厚度之比明显减少 (分别为 7.10± 0 .5 9比 9.2 4± 1.17,6.0 0± 0 .89比 8.96± 1.2 3 ) ,中膜厚度明显增加 (分别为 119.47± 10 .77μm比 91.5 5± 14.45 μm ,49.60± 1.0 4μm比 3 7.0 1± 4.85 μm ,P均 <0 .0 5 ) ,主动脉中磷酸化细胞外信号调节激酶的表达显著增强 ;氯沙坦治疗后 ,血压、心脏与体重之比分别下降到 13 2± 9mmHg、0 .3 2± 0 .0 3 (P均 <0 .0 5 ) ,主动脉和肠系膜动脉的内径与中膜厚度之比明显增加 ,中膜厚度明显减小 ,并下调主动脉中磷酸化细胞外信号调节激酶的表达。提示氯沙坦可明显改善两肾一夹型高血压大鼠的血管重塑 ,这种调节可能是通过细胞外信号调节激酶信号途经发挥作用的  相似文献   
20.
目的探讨及早鉴别用免疫学方法筛选cDNA文库得到的阳性克隆是否真实可靠的方法.方法将阳性噬菌体克隆与宿主菌按一定的比例诱导培养后,取沉淀做SDS-PAGE后行W estern b lot;同时取出一个阳性克隆进行亚克隆,直至3次亚克隆均为全部阳性.结果3次亚克隆均为全部阳性的噬菌体克隆,在W estern b lot鉴定中也呈阳性反应.结论可用W estern b lot方法来鉴别用免疫学方法筛选cDNA文库得到的阳性克隆是否真实可靠.  相似文献   
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