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991.
The immunohistochemical occurrence of the high affinity neurotrophin (NT) receptors trkA, trkB, and trkC is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. Immunoreactive neuronal perikarya and processes were observed in all specimens examined, where they appeared unevenly distributed in the cerebellar cortical layers and deep nuclei, and showed regional differences among cerebellar lobules and folia. The trk receptor-antibodies, tested by Western blot on human cerebellum homogenates, revealed multiple immunoreactive bands for trkA and single bands for trkB and trkC. The results obtained show the tissue localization of the trk receptor-like immunoreactivity in the human cerebellum from prenatal to adult age. The analysis for codistribution of the receptors with the relevant ligand and among the receptors in discrete cortical and deep nuclei tissue fields shows a wide variety of conditions, from a good similarity in terms of type and density of labeled structures, to a lack of correspondence, and suggests the possibility of colocalization of trk receptors with the relevant neurotrophin and among them in the cerebellar cortex. These results sustain the concept that the neurotrophin trophic system participates in the development, differentiation, and maintenance of the human cerebellar connectivity and support the possibility of a multifactorial trophic support for the neurotrophins through target-derived and local mechanisms.  相似文献   
992.
生物化学与细胞生物学课程整合的探讨   总被引:8,自引:0,他引:8  
为了适应新世纪教学内容和课程体系改革的要求,我校借鉴美国哈佛大学医学院的经验,将生物化学与细胞生物学两门课程整合为“细胞的化学与生物学”。整合后在减少两个学科间重复内容、增加学科间联系、减少学时、早期接触临床、培养学生分析解决问题的能力、创新能力等方面有了很大改进,为这两门课程的改革开辟了新途径。  相似文献   
993.
This paper examines delinquency as it relates to family influences.  相似文献   
994.
以史为鉴,直面SARS   总被引:1,自引:1,他引:0  
回顾影响我国古代疫病流行的各种因素,直接面对这次SARS危机,可以引出以下思考:①要尽快有效地战胜一种传染力极强的疫病,必须是一种政府行为,必须有一个有高度取信于民,而又敢于负责,务实高效的政府来统一领导。②应该珍惜安定团结的政治局面,努力发展生产,只有拥有了可靠的物质保障,才能有经得起风浪的能力。③合理控制人口、规划大城市的建设规模,是有效防疫的必要措施,这项工作做不好,很大程度上增加了防疫工作的难度,本次发生在我国大城市的SARS爆发流行值得警惕。  相似文献   
995.
陕西省2000~2002年麻疹流行病学分析及控制策略探讨   总被引:33,自引:3,他引:30  
为了解陕西省麻疹流行状况 ,以加速控制麻疹 ,对陕西省 2 0 0 0~ 2 0 0 2年麻疹发病资料进行流行病学分析。结果显示 :陕西省 2 0 0 0~ 2 0 0 2年麻疹年平均发病率比 1997~ 1999年上升了 6 5 7%。病例分布广泛 ,流行模式为爆发和散发并存 ,局部麻疹爆发影响着全省的麻疹发病水平。 3~ 6月为麻疹高发季节 ,0~ 2岁和 6~ 8岁为麻疹高发年龄组。对麻疹病例的免疫史分析表明 ,2 5 %的麻疹病例未接种麻疹疫苗 (MV) ,2 4 %的病例免疫史不详。报告病例的年龄和免疫史状况说明 ,MV的初种和复种需加强 ,同时要在全省范围开展一定年龄组儿童的MV强化免疫 ,调整现行MV的免疫程序 ,健全麻疹监测系统。  相似文献   
996.
某医科大学中老年教职工健康状况分析   总被引:6,自引:0,他引:6  
对1004名50岁以上中老年教职工进行健康检查。结果:健康者仅占11.25%,而88.75%的中老年教职工至少患有1例次疾病,最多患有5例次疾病,总例次患病率为186.95%,男女例次患病率分别为187.24%和186.62%,男女间无差异。前5位疾病的顺位是:心血管疾病、呼吸系疾病、脑血管疾病、消化系统病、泌尿生殖疾病。  相似文献   
997.
998.
文章对33例中老年肺尖和锁骨下区慢性结核作平片和肺尖断层对照分析。结果表明:断层对该部位慢性结核多形态病灶检出率和病情判断明显优于平片。着重对空洞、结核球和合并肺癌断层影像研究。肯定断层诊断价值。  相似文献   
999.
A lymph node metastasis in the neck or parotid region from an unknown primary melanoma is an uncommon occurrence. Out of a total of 300 patients with head and neck melanoma treated at the Netherlands Cancer Institute between 1976 and 1992, 17 (5.7%) presented in this way. The most common site for metastatic lymph nodes (18 nodes in 17 patients) was level V (n= 7), followed by the parotid region (n= 4), level II (n= 4), level III (n= 2), and level IV (n= 7). Two patients had local excision of the neck node metastasis only, while the remaining 15 patients underwent more extensive surgical treatment. The 5-year disease-specific survival rate in this group was 48%, with a median survival of 36 months, which is more or less similar to the prognosis of stage II melanoma of the head and neck with a known, surgically treated primary tumour. No relation was found between disease-free interval and sex, the number of positive lymph nodes or the duration of symptoms.  相似文献   
1000.
Summary Insulin binding to trophoblast plasma membranes and the placental glycogen content were measured in twelve healthy women, in eleven well-controlled gestational diabetic women who were treated either with diet alone (n=4) or with insulin (n=7) and in 18 women with well-controlled overt diabetes mellitus (six White B; four White C; eight White D). The competitive binding assay was carried out with 22 concentrations of unlabelled insulin. Binding data were analysed by a non-linear direct model fitting procedure assuming one non-cooperative binding site. Maximum specific binding was unchanged in the total collective of gestational diabetic women, but was decreased by 30% in those treated with diet (6.2±2.2%) and increased by 90% in insulin-treated women (16.4±10.2%) as compared to the control subjects (8.7±2.5%). The diet-treated women had only 40% as many and those treated with insulin had more than twice as many receptors compared to control subjects on a per mg protein basis and if expressed per total placenta. In patients with overt diabetes mellitus maximum specific binding (18.5±10.6 %) was higher (p<0.05) due to more receptors compared to control subjects but was similar to the insulin-treated gestational diabetic patients. Maximum specific binding and receptor concentrations did not correlate linearly with maternal plasma insulin levels. Receptor affinities were virtually similar in all groups (1.8·109 l/mol). The placental glycogen content was reduced (p<0.05) to about 80% of that of control subjects in the diet-treated collective, whereas it was unchanged compared to control subjects in the insulin-treated gestational diabetic women despite a 40% increase (p<0.001) of the maternal-to-cord serum glucose ratio. In overt diabetic patients the maternal-to-cord serum glucose ratio and the placental glycogen content were higher (p<0.05) than in the control subjects. We conclude that trophoblast plasma membranes from gestational diabetic women treated with diet alone express less and those from women treated with insulin express more insulin receptors than those from a healthy control group in vitro. These differences could not have been disclosed without consideration of the mode of treatment. Trophoblast plasma membranes from overt diabetic women have more insulin receptors than those from healthy control subjects.  相似文献   
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