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41.
电针肾俞、膈俞、百会穴对拟血管性痴呆学习记忆障碍小鼠水迷宫实验的影响 总被引:9,自引:1,他引:8
目的 观察电针肾俞、膈俞、百会穴对拟血管性痴呆小鼠学习记忆障碍的影响。方法 复制脑缺血再灌注拟血管性痴呆小鼠模型 ,并电针肾俞、膈俞、百会穴 ,分别于术后 7天、15天、30天 ,与药物喜德镇对照 ,采用水迷宫法 ,记录游全程时间、错误次数。结果 造模导致了小鼠学习与记忆能力下降 ,表现为游全程时间延长 ,错误次数增加 ,且随着观察时间的延长 ,这种改变逐渐加重。电针和喜德镇均可使模型小鼠的游全程时间缩短 ,错误次数减少 ,但电针组于 7天和 30天时 ,成绩显著优于药物组。结论 电针肾俞、膈俞、百会穴对模型小鼠学习与记忆能力下降有改善和提高作用 相似文献
42.
At the turn of the last century, side by side with the infiltration of religious culture from Western countries, western medicine spread into Yantai. The religious force, headed by American Presbyterian Mission, carried out charitable activities in the process of preaching and laid down the foundation for western medicine rooted in Yantai by establishing schools, education and training followers. They cultivated local physicians by first setting up clinics which had later transformed into hospitals. These are their major measures for building bases for spreading Christianity by foreigners. The Temple Hill Hospital set up by the American physician Oscar F. Hills in Yantai was a successful example of mutual promotion of missionary and medical activities which pushed forward the spreading and development of western medicine in Yantai. 相似文献
43.
44.
GABA(A) receptors mediate inhibition of T cell responses 总被引:4,自引:0,他引:4
We describe the presence of functional GABA(A) receptors on T cells. GABA inhibited anti-CD3 and antigen-specific T cell proliferation in vitro in a dose-dependent manner that was 1) mimicked by the GABA(A) receptor agonist muscimol (but not the GABA(B) receptor agonist baclofen), 2) blocked by GABA(A) receptor antagonists and a GABA(A) receptor Cl- channel blocker (picrotoxin) and 3) enhanced by pentobarbital. These data suggest that GABA(A) receptors mediate this immune inhibition and that these receptors can be modulated in a similar fashion to their neuronal counterparts. Finally, GABA inhibited DTH responses in vivo. Thus, pharmacological modulation of GABA(A) receptors may provide new approaches to modulate T cell responses in inflammation and autoimmune disease. 相似文献
45.
46.
Protein kinase C has been implicated as a cellular target for Pb2+ toxicity. We have previously proposed that Pb2+ modulates PKC activity by interacting with multiple sites within the enzyme. In order to further characterize the Pb-PKC interactions we compared the effects of Pb2+ on the CA-dependent and -independent protein kinase C isozymes using recombinant human PKC-alpha, PKC-epsilon, and PKC-zeta as well as the catalytic fragment of bovine brain protein kinase C, the PKC-M. The results demonstrate that, whereas at pM concentrations Pb2+ activates PKC-alpha half maximally (KAct approximately 2 pM), it has no effect on PKC-epsilon, PKC-zeta, or PKC-M activities. The activation of PKC-alpha by Pb2+ is additive with Ca2+ in a manner indicating interaction with half of the calcium activation sites. In the micromolar range of concentrations, Pb2+ inhibits all PKCs with estimated K0.5 of 1.0, 2.3, 28, and 93 microM for PKC-M, PKC-alpha, PKC-epsilon, and PKC-zeta, respectively. Examination of Pb2+ effects on PKC-M kinetics indicates a mixed type inhibition with respect to ATP and noncompetitive inhibition with respect to histone. Taken together with the results of our previous study (Tomsig and Suszkiw, J. Neurochem. 64, 2667-2673, 1995) and the evidence for the existence of two Ca2+ coordination sites Ca1 and Ca2 within the C2 domain (Shao et al., Science [Washington, D.C.] 273, 248-251, 1996), the results of the current study provide further support for a multisite Pb-PKC interaction scheme wherein lead (1) partially activates the enzyme through pM-affinity interactions with the Ca1 site and inhibits the divalent cation-dependent activity through nM-affinity interactions with Ca2 site in the C2 domain and (2) inhibits the constitutive kinase activity through microM-affinity interactions with the catalytic domain. The concentration dependence of the differential effects of Pb2+ on the calcium-dependent and -independent PKCs underscores the importance of the C2 motif as a high affinity molecular target for Pb2+. 相似文献
47.
The natural history of classic mucinous cystic neoplasms of the pancreas has been previously defined. In this report, an unusual variant of a pancreatic mucinous cystic neoplasm, termed "mucinous pancreatic duct ectasia of latent malignancy," is described. The lesion is characterized by massive dilatation of the main pancreatic duct and its tributaries. Histologically, the ducts are lined by epithelium, which is indistinguishable from the classic mucinous cystic neoplasms. Until the natural history of classic mucinous cystic neoplasm is better documented, resection appears to be the treatment of choice. 相似文献
48.
目的探讨维甲酸(retinoic acids,RA)对鼻咽癌细胞株HNE1生长及表型的作用,同时观察维甲酸诱导鼻咽癌细胞株HNE1后细胞角蛋白基因13(cytokeratin 13,CK13)表达情况。方法应用细胞培养的方法观察维甲酸诱导鼻咽癌细胞株HNE1细胞的生长状况,利用Northern杂交技术分析维甲酸诱导鼻咽癌细胞株HNE1后CK13基因的表达。结果维甲酸能显著抑制鼻咽癌细胞的生长,抑制的强度取决于维甲酸的浓度和诱导持续时间,当维甲酸的浓度为1×10-4 M/L时,前4天下降约50%,第5天开始细胞停止增殖,细胞数逐渐减少,细胞逐渐老化死亡。维甲酸处理后的鼻咽癌细胞从典型的多边形变成扁平、细长,类似纤维细胞的形态。维甲酸诱导后的鼻咽癌细胞中CK13基因的表达明显上调,且与维甲酸的浓度有关。结论维甲酸能促进鼻咽癌细胞的分化,可能是通过上调CK13基因的表达而实现的。 相似文献
49.
喉癌组织恶性度与颈淋巴结转移关系 总被引:2,自引:0,他引:2
采用五因素评点法对40例喉鳞癌进行组织学和临床方面的研究。结果表明,组织恶性度与T分期无相关性,浸润方式弥散及恶性度高(评分≥11)的肿瘤发生颈淋巴结转移率显著高于有完整肿瘤边界者及恶性度低(评分≤10)者。提示喉癌组织恶性度在预测颈淋巴结转移上有实用价值,可临导临床治疗方案的选择。 相似文献
50.
妊娠期糖尿病患者高密度脂蛋白糖基化与妊高征发病的关系 总被引:1,自引:0,他引:1
目的:了解妊娠期糖尿病孕妇体内高密度脂蛋白(HDL)糖化程度及受体代谢途径情况,探讨其与妊高征发病的关系。方法:用荧光法测定妊娠期糖尿病患者糖化血红蛋白,≤8.0%为组Ⅰ,共32例、>8.0%为组Ⅱ,共34例,并测定正常妊娠组36例及正常非妊娠组32例HDL糖化值。用酶联免疫受体法观察HDL与培养的人胚肺成纤维细胞表面受体特异结合情况。结果:妊娠期糖尿病患者组Ⅰ、组ⅡHDL糖化值明显高于正常妊娠组和正常非妊娠组(P<0.01)。其细胞结合、摄入和降解糖化HDL均较正常妊娠组和正常非妊娠组升高,使细胞内总胆固醇含量升高(P<0.01)。结论:妊娠期糖尿病患者HDL糖化值含量的变化及脂质沉积,可能是妊高征小动脉痉挛的原因之一。 相似文献