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61.
62.
While IL-12 administration induces tumor regression through stimulating T cells in tumor-bearing mice, this IL-12 effect is observed in some but not all tumor models. The present study aimed to compare IL-12 responsiveness of T cells from tumor-bearing mice in IL-12-responsive (CSA1M and OV-HM) and -unresponsive (Meth A) tumor models. Tumor regression in IL-12-responsive tumor models required the participation of T cells, but not of NK1.1(+) cells. Because a NK1.1(+) cell population was the major producer of IFN-gamma, comparable levels of IFN-gamma production were induced in IL-12-responsive and -unresponsive tumor-bearing mice. This indicates that the amount of IFN-gamma produced in tumor-bearing individuals does not correlate with the anti-tumor efficacy of IL-12. In contrast, IL-12 responsiveness of T cells differed between the responsive and unresponsive models: purified T cells from CSA1M/OV-HM-bearing or Meth A-bearing mice exhibited high or low IL-12 responsiveness respectively, when evaluated by the amounts of IFN-gamma produced in response to IL-12. T cells from CSA1M- or OV-HM-bearing but not from Meth A-bearing mice exhibited enhanced levels of mRNA for the IL-12 receptor (IL-12R). These results indicate that a fundamental difference exists in IL-12 responsiveness of T cells between IL-12-responsive and -unresponsive tumor models, and that such a difference is associated with the expression of IL-12R on T cells.  相似文献   
63.
Voltage-gated Ca(2+) channels (VGCCs) are important in regulating a variety of cellular functions in neurons. It remains poorly understood how VGCCs with different functions are sorted within neurons. Here we show that the t-complex testis-expressed 1 (tctex1) protein, a light-chain subunit of the dynein motor complex, interacts directly and selectively with N- and P/Q-type Ca(2+) channels, but not L-type Ca(2+) channels. The interaction is insensitive to Ca(2+). Overexpression in hippocampal neurons of a channel fragment containing the binding domain for tctex1 significantly decreases the surface expression of endogenous N- and P/Q-type Ca(2+) channels but not L-type Ca(2+) channels, as determined by immunostaining. Furthermore, disruption of the tctex1-Ca(2+) channel interaction significantly reduces the Ca(2+) current density in hippocampal neurons. These results underscore the importance of the specific tctex1-channel interaction in determining sorting and trafficking of neuronal Ca(2+) channels with different functionalities.  相似文献   
64.
Dopamine plays important roles in the regulation of central nervous system (CNS) development and functions. In vertebrates, two families of dopamine receptors, collectively known as dopamine D1 and D2 receptors, have been identified. Recently, dopamine receptors have been targeted by pharmacological and therapeutic studies of neurological disorders, such as Parkinson's disease. Here, we report a study on the molecular characterization of dopamine D1 receptor in zebrafish (Danio rerio). We cloned the full-length cDNA of a zebrafish dopamine D1 receptor, designated as drd1. The sequence of drd1 shares high homology to the sequences of dopamine D1 receptors in mammalian, amphibian, and other fish species. drd1 is expressed in the CNS. The first drd1 expression was observed at approximately 30 hours postfertilization, at which time the expression was seen in the developing diencephalon and hindbrain. In developing retinas, the expression of drd1 was detected in the inner nuclear layer with the exception of the marginal zones. In adult retinas, drd1 expression was detected in most cell types in the inner and outer nuclear layers as well as ganglion cell layer. Differential expression of drd1 in developing and adult retinas may play various roles in regulating visual system functions.  相似文献   
65.
The ospC genes of 20 southern Borrelia strains were sequenced. The strains consisted of B. burgdorferi sensu stricto, B. andersonii, B. bissettii, one undescribed genospecies, MI-8, and one probably new Borrelia species, TXW-1. A high degree of similarity exists between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Lateral transfers of the ospC gene probably occurred between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Internal gene recombination appears to occur among them. The highest degree of genetic diversity among them was observed in the two variable domains (V1 and V2), semivariable domain (SV), and the species-specific epitopes (between amino acids 28 and 31). Differences in ospC sequences among southern strains reflect diversity at the strain and genospecies levels. MI-8, which was recognized as an undescribed genospecies in our previous reports, remains distinguishable in our current analysis of ospC genes and is distinct from B. burgdorferi sensu stricto. Interestingly, another undescribed southern isolate, TXW-1, was not amplified under various PCR conditions. Compared to European B. burgdorferi sensu stricto strains, American B. burgdorferi sensu stricto strains show greater genetic heterogeneity. Southern B. burgdorferi sensu stricto, B. andersonii, and B. bissettii isolates were intermixed with each other in the phylogenetic trees. In the derived trees in our work, at least one southeastern strain of B. burgdorferi, MI-2, most closely aligns with a so-called invasive cluster that possesses many proven human-invasive strains. Transmission experiments show that MI-2 and the strains in this group of southern spirochetes are able to infect mice and hamsters and that the typical vector of Lyme disease, Ixodes scapularis, can acquire the spirochetes from infected mammals. Currently, strain MI-2 appears to be the only southern isolate among the 20 we analyzed that clusters with an OspC invasive group and thus might be invasive for humans.  相似文献   
66.
67.
新洁尔灭对小白鼠抗早孕的病理组织学观察   总被引:3,自引:0,他引:3  
本文报告用不同剂量的新洁尔灭和同体积生理盐水注入怀孕5天小白鼠的宫腔内,3天后杀死,观察其蜕膜、胚泡、宫内膜腺体和卵巢黄体病理学改变。实验表明:对照组无改变。实验组小白鼠的蜕膜细胞全部退变坏死。病变随着给药量的递增而渐趋严重;同时胚泡亦有退变和坏死。提示:新洁尔灭对早期妊娠小白鼠是有抗早孕效果的。根据实验结果,我们认为新洁尔灭对小白鼠抗早孕的机制,很可能是一个综合因素,有直接的,也有间接的。作者强调在抗早孕机制诸因素中,蜕膜退变坏死是一个重要的因素。  相似文献   
68.
The concept and taxonomy of periodic psychosis still remains in controversy for the past 100 years. In China, it was first reported by Ji, and thereafter various rinds of terminology and views were given by different authors. In the presentation, clinical investigation and follow up were carried out in 62 cases. In many of these cases, the so-called "periodic psychosis" or "phasophrenia" was early clinical features of schizophrenia or manic-depression. In those cases with apparent symptoms and signs of diencephalic function, differential diagnosis should be carried out from organic brain syndrome. In a small number of cases, their clinical manifestations, conforming to previous diagnostic criteria, might be an uncommon syndrome. It was concluded by the authors that until now periodic could be considered only as a clinical syndrome rather than a disease entity.  相似文献   
69.
单纯性肥胖症瘦素水平的临床意义   总被引:2,自引:0,他引:2  
目的 :探讨单纯性肥胖症血清瘦素 (Leptin)及其临床意义。方法 :用ELISA法检测 48例单纯性肥胖症 (体重指数≥ 2 5 )和 40例健康对照者的血清Leptin水平。结果 :肥胖症组血清瘦素水平明显高于健康对照组 (P <0 .0 0 1) ,女性几乎较男性高 2倍以上。瘦素与BMI及脂肪含量呈正相关 (相关系数r分别为男性r =0 .36 ,0 .33 ,P <0 .0 5 ;女性r =0 .90 ,0 .87,P <0 .0 5 )。结论 :单纯性肥胖症血清瘦素水平升高 ,提示瘦素抵抗存在 ,可能在肥胖的发生发展中起重要作用  相似文献   
70.
目的 研究心肌梗塞(MI)后心室胶原生化改建与心脏肾素-血管紧张素系统(RAS)的关系。方法 采用放射免疫等方法动态观测了大鼠MI后3、15及42天左、右心室胶原含量、总量和血管紧张素Ⅱ(AngⅡ)含量以及血浆AngⅡ含量的变化,结果 血浆AngⅡ含量仅在MI后3天有一过性升高;MI鼠左、右心室AngⅡ含量以及血浆AngⅡ含量的变化。结果 血浆AngⅡ含量仅在MI后3天有一过性升高;MI鼠左、右心室AngⅡ含量于3天时就明显升高,此后一直保持在3天时水平,MI后左、右心室胶原基质均发生了生化改建,除右心室胶原生化建建稍滞后于其AngⅡ的变化外,左、右心室的胶原生化改建与其心肌AngⅡ的变化形式基本一致。结论 MI后心脏RAS被明显激活;心肌AngⅡ在心肌胶原生化改建的过程中可能起着重要的作用。而且其作用不依赖于循环RAS。  相似文献   
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