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51.
52.
抑郁症的基础与认知激活脑SPECT显像 总被引:17,自引:6,他引:11
目的通过抑郁症患者基础和认知激活局部脑血流(rCBF)灌注显像的半定量分析,评估抑郁症患者的脑血流灌注异常。方法选择27例未经抗抑郁治疗、ICD10分类为中度抑郁发作伴躯体症状的患者,15例年龄匹配的健康人作正常对照。27例患者中21例、15例健康人中13例行双日法基础与认知激活脑rCBF显像;另6例患者及2例健康人仅行基础脑SPECT显像。认知激活采用Wisconsin卡片分类试验。半定量分析在横断面图像7~11帧上进行,将各ROI的平均计数与同侧小脑的最高计数相除,得到各ROI的rCBF比值。结果抑郁症左额叶和左颞叶的基础rCBF值均为0720,明显低于对照组(0764和0750,P<005);左额、左颞、左顶叶的认知激活rCBF值分别为0719、0690及0701,明显低于对照组(0782、0752和0766,P<001和P<005)。结论①抑郁症患者存在左额叶、左颞叶的局部血流低灌注。②额叶、颞叶皮层低灌注可能是引起抑郁症认知障碍、心境低落的原因。③Wisconsin卡片分类试验认知激活脑SPECT显像有助于提高抑郁症的诊断准确性 相似文献
53.
A relatively nonhygroscopic crystalline form of the glycopeptide, N-acetylmuramyl-L--aminobu-tyryl-D-isoglutamine (I), containing approximately one molecule of water was prepared from amorphous material. The crystalline material, consisting of a mixture of the and anomers, exhibited better physical and chemical stability than the lyophilized amorphous material. The /-anomer ratios of I in both the crystalline and the amorphous state were approximately equal but different from that in solution. 相似文献
54.
Allele-specific differential expression of a common adiponectin gene polymorphism related to obesity 总被引:14,自引:0,他引:14
Yang WS Tsou PL Lee WJ Tseng DL Chen CL Peng CC Lee KC Chen MJ Huang CJ Tai TY Chuang LM 《Journal of molecular medicine (Berlin, Germany)》2003,81(7):428-434
Adiponectin gene polymorphisms have recently been reported to be associated with obesity, insulin sensitivity, and the risk of type 2 diabetes. We examined a T94G polymorphism of the adiponectin gene in 245 ostensibly normal nondiabetic subjects. The G allele frequency was lower among subjects with higher BMI (> or =27) than in those with lower BMI. BMI was inversely correlated with the dose of G allele. Multivariate linear regression analyses showed that the adiponectin genotypes were significantly related to BMI after adjusting for age and gender. The dose of the G allele was associated with a reduction of approximately 1.12 kg/m(2) in BMI. We further found that the relative mRNA levels of G allele were consistently higher than those of T allele in the omental adipose tissue from 21 heterozygous subjects. Finally, we observed that the expression levels of adiponectin affected insulin-stimulated glucose uptake in differentiated 3T3-L1 adipocytes. In conclusion, the allele-specific differential expression of this common polymorphism could be responsible for its biological effects observed in this and the other studies. 相似文献
55.
不同全麻药对小鼠周围神经电生理的影响 总被引:4,自引:0,他引:4
目的:探讨全麻药对小鼠周围运动神经和感觉神经的影响。方法:将50只小鼠分为5组,分别是用α-氯醛糖、戊巴比妥钠、氨基甲酸乙酯、水合氯醛、氯胺酮进行腹腔麻醉后,测定坐骨神经感觉神经动作电位(SNAP)和腓肠肌复合肌肉动作电位(CMAP),并比较其潜伏期、波幅、传导速度。结果:氯胺酮组的SNAP和CMAP的传导速度都最快,而α-氯醛糖组的SNAP的潜伏期、波幅、传导速度都最差。结论:在实验性研究或临床应用周围神经电生理检测时,选用氯胺酮或戊巴比妥钠麻醉较为理想。 相似文献
56.
Cell extract-derived differentiation of embryonic stem cells 总被引:1,自引:0,他引:1
Various means have been used to encourage the differentiation of embryonic stem cells (ESCs) toward specific lineages, including growth factor administration, genetic modification, and coculture with relevant cells/tissues. Cell extract-based reprogramming has recently been used to derive mature cells from nonrelated phenotypes. In this communication, we tested whether this in vitro reprogramming approach can be used to direct ESC differentiation. Permeabilized murine ESCs exposed to extracts of murine type II pneumocytes showed increased expression of surfactant protein C and its corresponding mRNA, reflecting enhanced differentiation of pneumocytes. Subsequent differentiation to a type I phenotype was demonstrated by expression of aquaporin 5. Pneumocyte formation occurred quicker than with growth factor-induced differentiation. Our findings establish that ESCs can be differentiated in vitro using cellular extracts. This model provides a tool for analysis of the key factors involved in the differentiation of ESCs to type II pneumocytes. 相似文献
57.
孕鼠被动吸烟对子代学习记忆功能及海马神经生长因子含量的影响 总被引:5,自引:0,他引:5
目的 探讨孕鼠被动吸烟对子代学习记忆功能的影响及其机制。方法 采用反映学习记忆功能的水迷宫法测试大鼠神经行为的改变,IRMA法测定大鼠海马神经生长因子的含量变化。结果 孕期被动吸烟使仔鼠学习记忆能力下降,海马神经生长因子含量明显降低。结论 孕期被动吸烟降低仔鼠学习记忆功能与海马神经生长因子代谢的失调有关。 相似文献
58.
Yu Wen-Gong; Yamamoto Noriniko; Takenaka Hiroshi; Mu Jie; Tai Xu-Guang; Zou Jian-Ping; Ogowa Makoto; Tsutsui Tateki; Wijesuriya Rishani; Yoshida Ryotaro; Herrmann Steven; Fujiwara Hiromi; Hamaoka Toshiyuki 《International immunology》1996,8(6):855-865
The present studnt Investigates the molecular by which IFN-produced as a result of in vitroIL-12 addministration exertsits anty-tumor,rIL-12 was administered three or five times intomice bearing CDA1M fibrosarcoma, OV-HM ovarian carcinoma orMCH-1-A1 fibosarcoma. This regimen induced complete regressionof CSA1M and OV-HM tumors but only transient growth inhibitionof MCH-1-A1 tumors. The anty-tumor effects of Il-12 were associatatedwith enhanced induction of IFN-becouse these effects were abrogatedby pretreatment of hosts with anti-IFN- antibody.Exposure inin vitro of the three types of tumor cells to rIFN- resultedin moderate to potent inhibition of tumor cell growth.IFNstimulatedthe expression of mRNAs for an inducible type of NO synthasa(INOS)in CSA1M cells and indoleamine 2,3-dioxygenasa (IDO),an enzyme capable of degrading tryptophan, in OV-HM cells ,but induced only marginal levels of these mRNAs in MCH-I-ALcells. In association withiNOS gene expression, INF--stimulatedCSA1M cells produced a large amount of NO which functioned toinhibit their own growth in vitro. Although OV-HM and MCH-1-A1cells did not produce NO, they also exhibited NO susceptibility.Whereasthe tumor masses from IL-12-treated CSA1M-bearing mice inducedhigher levels of INOS (for CSA1M) or IDO and iNOS (for OV-HM)mRNAs,the MCH-1-A1 tumor mass expressed lower levels of iNOS mRNAalone.Moreover, massive infiltration of CD4+and CD8+ T cellsand Mac-1+ cells was seen only in the CSA1M and OV-HM tumors.Thus, these results indicate that IFN- produced after IL-12treatment induces the expression of various genes with potentialto modulate tumor cells and growth by acting directly on tumorecells or stimulating tumor-infiltrating lymphold cells and thatthe effectiveness of IL12 therapy is assoiated with the operation if these mechanisms. 相似文献
59.
Normal human B lymphocytes and mononuclear cells respond to the mitogenic and cytokine-stimulatory activities of Borrelia burgdorferi and its lipoprotein OspA. 总被引:1,自引:10,他引:1 下载免费PDF全文
Borrelia burgdorferi produces potent cell-activating molecules capable of stimulating polyclonal proliferation and immunoglobulin production by murine B lymphocytes and cytokine production by a variety of cell types. These stimulatory molecules function in infected mice, resulting in elevated levels of circulating immunoglobulins and serum interleukin-6. We have recently demonstrated that the purified outer surface lipoproteins OspA and OspB possess these properties. To assess their possible involvement in human disease, we determined whether cells from normal human donors could respond to these activities. Normal human B lymphocytes but not T lymphocytes proliferated when incubated with either sonicated B. burgdorferi or purified OspA. Sonicated B. burgdorferi was efficient at stimulating immunoglobulin M production by human mononuclear cell cultures; however, purified OspA was relatively inactive. Both sonicated B. burgdorferi and purified OspA stimulated production of high levels of interleukin-6 by mononuclear cells. These findings extend our observations with the mouse model and suggest that the stimulatory lipoproteins could indeed be involved in the symptoms and pathologies of human infection with B. burgdorferi. 相似文献
60.
蒙古族、回族和汉族的发旋调查 总被引:2,自引:0,他引:2
对蒙古族、回族和汉族共6098例发旋进行了观察,结果:蒙古族单旋出现率高于回族和汉族,而双旋则低于这两个民族,差异极其显著(P<0.01)。三个民族男性双旋均高于本民族女性(P<0.01)。双旋的组合除文献报道的四种类型外,还有四种组合方式。 相似文献