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171.
本文从下丘脑、大脑皮层、海马等脑区去甲肾上腺素(NA)的含量,其合成酶与降解酶的活性、NA受体数目等多环节的测定来分析肾上腺素能神经递质系统在老化脑中的变化。实验结果表明衰老过程下丘脑、大脑皮层内NA合成酶活性没变化,NA含量明显增高,下丘脑内α_1受体数目显著减少。上述结果提示这些脑区肾上腺素能神经的活动有可能减弱。同时,海马内单胺氧化酶B(MAO B)活性明显增加,说明海马神经元外组织有增生的可能。泰文并讨论了这些变化与老年记忆、行为与神经内分泌等脑功能衰退的关系。 相似文献
172.
本文用免疫荧光法与 Giemsa 氏法检测明显沙眼患者,两法阳性率相差无几。但在临床肉眼观察认为正常时,其阳性率分别为24.77%及11.58%(P<0.05),差异有显著意义,表明免疫荧光法检测早期沙眼较 Giemsa 氏法敏感。临床认为正常眼,经实验室检查25.56%为阳性,说明开展沙眼的实验室诊断是必要的。 相似文献
173.
抗人生长激素免疫血清的制备和鉴定 总被引:1,自引:1,他引:0
Using small dosage of human growth hormone to immunize rabbit or guinea pig, it is able to induce anti-hGH antibody formation with high titre and high affinity that could be applied to hGH RIA. In the present study five rabbits and three guinea pigs were immunized with 125-200 micrograms and 250-285 micrograms per animal of hGH respectively, followed by boosters of 10-20 or 160-250 micrograms of hGH at 2-4 week intervals for 6 or 3 months. Blood was drown 1-2 weeks before each booster for determination of antibody formation. Antibody titre and affinity were successively observed and specificity of antibody was determined for the final bleeding. It was shown that titres of immune sera from guinea pigs were much higher than those of rabbit immune sera, but vice versa for antibody affinity. This might be due to larger immunogen dose used for guinea pigs than for rabbits. Fourteen different peptide hormones were tested in reference to cross-immunoreactivity to anti-hGH antibody. It could be demonstrated that the major cross-reactive hormones are hFSH and hLH, and hTSH also reacts to rabbit anti-hGH immune sera at a lesser degree. These cross reactivities are obviously owing to the molecular homogeneities between hGH and these hormones especially of their alpha-subunits. 相似文献
174.
王周 《公共卫生与预防医学》2007,18(4):129-130
为了解少数民族女大学生对生理卫生常识及艾滋病(AIDS)相关知识的掌握情况,中央民委于2007年3月对所属7大民族院校的2006级新生(女)进行了问卷调查,为探索少数民族院校健康教育模式提供科学依据,现报告如下。1对象与方法1.1对象2007年3月调查中南民族大学2006级(新生)女大学生2 相似文献
175.
176.
Different characteristic damages of the SGC-7901 gastric adenocarcinoma cells were studied by electron microscopy 1, 36, 72, 96 and 120 hours after heating and radiation in vitro. The visible damages, such as the enlarged mitochondria, increase of lysosomes and perichromatin granules could be shown 1 hour after heating (43 degrees C for 30 min) but no visible damages of the cells were shown until 36 hours following radiation (500 rad). In order to study the ultrastructural changes of the gastric cancer cells in mitosis after heating and radiation, we have used the new method of ultrastructural research in selecting and observing the M cell in vitro and found loosened structure of chromosome and disappearance of microtubules 1 hour following hyperthermia. At the same time, no apparent abnormalities of the mitotic cells were observed after radiation. It is the chief cause of division delay in heat injured cells. However, the chromosomes and microtubules of the new mitotic cells could recover 36 hours after heating (43 degrees C for 30 min). After radiation, the giant cells and abnormal morphologic changes of cells gradually increase and the living cells decrease. Unexpectedly, the division of a few giant cells is observed 72 hours after heating and radiation. 相似文献
177.
178.
Zhou Zhong-yuan周中源 Zhao Wei-bin赵蔚斌 Fu Xin-xiang傅信祥Shanghai Fourth People''s Hospital Shanghai 《中华医学杂志(英文版)》1987,100(2):118-121
Plasma testosterone and estradiol are determined
in 72 patients with abnormal high density lipoprotein.
cholesterol (HDL-C) and high density lipoprotein
cholesterol/total cholesterol (H/T) ratio values, and
in 72 randomly chosen males with normal HDLC
and H/T values. The results showed that plasma
testosterone levels in the groups with abnormal
HDL-C and H/T were obviously lower than those
in the controls. Statistically significant differences
were found in all the abnormal groups in comparison
with the controls (P0.20).
Testosterone levels lowered further with increasing
age in the groups with abnormal HDL-C and H/T.,
the most obvious drops were in the groups around
56 years of age (P<0.005). The data indicate that
male hormone deficiency may reduce HDL-C and
H.'T and facilitate the process of atherosclero_is.
Therefore, it seems rational to treat such patients
with male sex hormone preparations or to use the
traditional Chinese medicines which strengthen Yang
(maleness) in a new attempt to treat and prevent
CHD. 相似文献
179.
Christian J Streck Paxton V Dickson Catherine Y C Ng Junfang Zhou John T Gray Amit C Nathwani Andrew M Davidoff 《Clinical cancer research》2005,11(16):6020-6029
PURPOSE: Type I IFNs (IFN-alpha/beta) have shown significant antitumor activity in preclinical models but limited efficacy and significant toxicity in clinical trials. We hypothesized that the antitumor activity of type I IFNs could be enhanced by chronic, low-dose systemic delivery and sought to test this in murine neuroblastoma models. EXPERIMENTAL DESIGN: Continuous liver-generated expression of human IFN-beta (hINF-beta) was achieved through a gene therapy-mediated approach using adeno-associated virus vectors encoding hIFN-beta (AAV hINF-beta). Orthotopic localized retroperitoneal and disseminated models of neuroblastoma were established using three different xenografts. Immunohistochemical analysis and ELISA were used to evaluate the antiangiogenic effect of therapy. RESULTS: The development of both localized orthotopic (retroperitoneal) and disseminated neuroblastoma was prevented in all mice expressing hINF-beta. Continued growth of established retroperitoneal tumors, treated with AAV hINF-beta as monotherapy, was significantly restricted, and survival for mice with established, disseminated disease was significantly prolonged following administration of AAV hINF-beta. Analysis of treated tumors revealed a significant antiangiogenic effect. Mean intratumoral vessel density was diminished and expression of the angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor were both decreased. Finally, combination therapy in which AAV hIFN-beta was used together with low-dose cyclophosphamide resulted in regression of both established retroperitoneal and disseminated disease. CONCLUSIONS: AAV-mediated delivery of hIFN-beta when used as monotherapy was able to restrict neuroblastoma growth due in part to inhibition of angiogenesis. When used in combination with conventional chemotherapy, AAV hIFN-beta was able to effect complete tumor regression. 相似文献
180.