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101.
白细胞介素—2新的功能位点及其中枢镇痛作用 总被引:2,自引:0,他引:2
白细胞介素-2(IL-2)不仅是重要的免疫调节因子,而且还具有重要的中枢调节作用。本实验以钾离子透入引起大鼠甩尾反应为指标,发现侧脑室注射IL—2能显著提高动物痛阈,并能被纳洛酮所阻断,表示IL-2的中枢镇痛作用可能与阿片受体有关。利用基因定位突变技术获得的无免疫活性IL-2实查体仍具有中枢镇痛作用,表明IL—2分子上发挥镇痛和免疫调节作用的功能位点是相互独立的。纳洛酮能够阻断IL—2的中枢镇痛作用,而不能影响IL—2增殖CTLL-2细胞的作用,提示IL-2发挥镇痛和免疫调节作用可能通过不同的受体途径。IL-2分子中第45位Tyr残基突变为Val后,虽仍保留了免疫活性,但丧失了镇痛功能,表示45位Tyr残基是IL—2发挥中枢镇痛功能的关键残基之一。我们推测IL—2的镇痛功能位点可能在IL—2分子中第45位Tyr残基附近区域。 相似文献
102.
Tissue and cell homogenates were prepared for PG and LDH study from 20 samples of histologically proven gastric cancer (GC), 6 samples of gastric cancer xenografts (THPGC-1) of different passages (GCXG) and cultured cells of 3 different gastric cancer cell lines (GCCL). Normal gastric mucosa (NGM) was also obtained from the resected stomach far distant from the primary tumor and histologically tumor free. The results indicated that the expression of PG isoenzymes was low or absent and the PG activities were significantly decreased in GC, GCXG and GCCL as compared to NGM. The activity of LDH was also significantly increased in GC, GCXG and GCCL. In addition, there was a change in isoenzyme pattern in GC and GCXG in which isoenzyme type M was observed whereas isoenzyme type H was preponderent in NGM. The results show that the human gastric cancer xenograft, THPGC-1, has biological properties very similar to those of the primary tumor suggesting that THPGC-1 is a reliable model for the study of the molecular biology of human gastric cancer. 相似文献
103.
104.
目的:提高X线对肺静脉异常连接的诊断准确性,为手术治疗提供可靠的依据。材料与方法:回顾性分析了11例肺静脉异常连接的X线胸片和病理生理改变,男3例,女8例,年龄8—34岁。从血液动力学变化分析了“8”字征,镰刀综合征等X线典型征象。结果:11例中完全性肺静脉异常连接4例,部分性7例。按部位分心上型6例;心内型4例;心下型1例。肺静脉异常连接或多或少合并房间隔缺损,法鲁氏三联症,以及右肺和肺动脉发育不全。结论:肺静脉异常连接的X线征象十分复杂而多变,因此,术前的仔细观察和精心判别对于手术治疗是非常重要的。 相似文献
105.
阳江高本底地区居民健康流行病学调查数据库与统计分析方法 总被引:1,自引:0,他引:1
目的 研究应用计算机数据库技术及先进统计分析方法,对阳江高本底地区10多万人20余年的健康随访研究资料和剂量学调查资料进行储存、管理和分析。方法 通过调研和比较分析,确定采用Foxbase系列数据库管理系统按专题建立数据库,借助于ID号实现记录连接;一般统计分析由SAS完成;交叉分组人年列表由Epicure中的Datab完成;癌症相对危险分析用AMFIT程序。结果 建立了40MB的各专题研究库,主要包括:10余万人的人口学数据库(1979~1995)、1.2万人的死因数据库(1979~1995)和526个村庄6783户、5273人的剂量数据库。提出了动态群组研究资料(1979~1986)与固定群组研究资料(1987~1995)的合并方法:首选方法是建立假想的基于记录连接的以1979年为起点的(固定)群组。另一方法是将不同阶段群组研究的人年表分层直接相加。计算了每个成员基于卧室内、起居室内、室外村平均剂量率与性别-年龄别居留因子的累积剂量。完成了以性别、atainedage、随访年代及剂量交叉分组的人年列表,对癌症死亡资料(1979~1990)进行了危险分析。结论 应用计算机数据库管理系统与统计分析技术使阳江高本底地区研 相似文献
106.
Good regulation of acupuncture in simple obesity patients with stomach-intestine excessive heat type 下载免费PDF全文
In order to investigate the regulatory effect of acupuncture on obesity patients with the Stomach-Intestine Excessive Heat Type, the pre-acupunctureal and post-acupunctural obesity index and biochemical indices of 718 simple obesity patients with Stomach-Intestine Excessive Heat Type were observed. It was showed that the marked weight loss effect was achieved in the cases by acupuncture, and the biochemical indices improved. It suggests that acupuncture had a optimal regulatory effect on the function of nerve, endocrine, digestion and energy metabolism. 相似文献
107.
108.
M K Sun 《Journal of the autonomic nervous system》1992,38(3):209-217
Electrical stimulation of the prefrontal cortex in anaesthetised, paralysed rats evokes transient hypotension. In this study we have endeavoured to determine whether this evoked response is mediated by the spinal cord-projecting vasomotor neurones of the rostroventrolateral medulla (RVL). The responses of RVL-spinal vasomotor neurones to electrical stimulation of the prefrontal cortex caused a period of inhibition of the neuronal activity in the majority of cases (11 out of 13 neurones tested, 85%) and a short period of excitation in the remaining 2 neurones (15%). The prefrontal cortex-evoked inhibition of RVL-spinal vasomotor neurones was eliminated by iontophoretic application of bicuculline, a GABAa receptor antagonist, to the RVL-spinal vasomotor neurones. Microinjection of 50 nl of bicuculline methiodide into the same area of the RVL where the neurones have been identified converted the prefrontal-evoked hypotension into a vasopressor response. These findings indicate that the hypotension evoked by stimulating the prefrontal cortex is mediated by GABAergic inhibition of the RVL-spinal vasomotor neurones. 相似文献
109.
Protein kinase C (PKC) is a family of at least seven closely related molecules (isozymes) that vary in terms of their requirements for activation and their distribution among cells of the brain. A striking example of this differential distribution is seen in the cerebellum, where Purkinje cells express PKC-I, an isozyme that is strongly activated by both phorbol ester (PE), and low doses of cis-unsaturated fatty acid (c-UFA), while granule cells predominantly express PKC-II, an isozyme that is strongly activated by PE but not c-UFA. Both Purkinje and granule cells have large, easily recorded voltage-gated K currents. These currents are attenuated by PKC activators in several other varieties of neuron. We hypothesized that the effects of these two PKC activators would be predicted by the distribution of the relevant PKC isozyme, and that the delayed outward rectifier current, IK, would be attenuated by both PE and c-UFA in Purkinje cells, but only by PE in granule cells. This hypothesis was confirmed in perforated-patch recordings. The attenuation produced by both activators could be blocked by application of a specific PKC inhibitor, RO-31-8220, and could not be mimicked by inert forms of PE or c-UFA. To our knowledge, this study represents the first report of an electrophysiological correlate of PKC isozyme distribution. 相似文献
110.
TPA (12-O-tetradecanoylphorbol-13-acetate), a potent tumor promoter, has been shown to stimulate or inhibit cell growth depending on the cell type investigated. We recently found that RT101 cells, a transformed mouse JB6 epidermal cell line, acquired a greater growth inhibition response to TPA during conventional subcultivation. The growth of low-passage RT101 cells was slightly inhibited by TPA in monolayer culture but stimulated in soft agar. In contrast, the growth of high-passage cells was greatly inhibited by TPA in both monolayer culture and in soft agar. Inhibition was dose dependent, directly correlated with protein kinase C-activating activities of tumor promoters, and was found to be reversible. TPA-treated high-passage cells were greatly reduced in volume, showed extensive abnormal mitoses, and were more susceptible to detachment. High-passage cells were also found to be less tumorigenic as indicated by in vivo tumorigenicity assay in nude mice. TPA treatment rendered cells still less tumorigenic in the case of both cell lines. The mechanism for acquisition of increased sensitivity to TPA of RT101 cells during subculture was investigated; it involved nonrandom DNA damage and detachment of nonviable cells. The results suggest the possibility that early-passage RT101 cells contained two subpopulations, one TPA-sensitive and one TPA-resistant population. Conventional subcultivation may have selected for the former subpopulation. The sensitive subpopulation may have been irreversibly inhibited as a result of TPA-induced cell killing, possibly apoptosis. 相似文献