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81.
目的:探讨大鼠中脑导水管周围灰质(PAG)内内源性强啡肽对神经降压素(NT)镇痛作用的影响。方法:以钾离子透入法引起大鼠甩尾反应的电流强度(mA)为痛行为反应的指标,观察向PAG内注入NT,抗神经降压素血清和抗强啡肽A1-13血清对动物痛阈的影响。结果:PAG内注入NT后,大鼠痛阈明显升高;注入抗神经降压素血清后,大鼠痛阈则明显降低,而注入抗强啡肽血清后,对NT的镇痛效应无显著影响,结论:PAG内NT在痛觉调制中发挥着重要的作用,且其作用不依赖于PAG内的内源性强啡肽。 相似文献
82.
Purpose. In a continuation of our search for novel antifungal compounds from higher plants, the standard extract of the bark of Pithecellobium racemosum was found to have good activity against important AIDS-related opportunistic yeasts.
Methods. The extract was subjected to bioguided fractionation using silica gel column chromatography which led to purification of triterpene glycosides. The structures of these compounds were determined by a combination of spectroscopic (IR, NMR, HRMS) and chemical methods.
Results. Compound 1 is a new glycoside, 3-O[-L-arabinopyranosyl (1 -2)][-L arabinopyranosyl (1 -6)]2-acetoamido-2-deoxy--D-gluco-pyranosyl oleanolic acid and Compound 2 was identified as the known compound 3-O-[-L-arabinopyranosyl (l-2)]-L-arabinopyranosyl (1-6)] 2-acetamido-2-deoxy--D-glucopyranosyl echinocystic acid.
Conclusions. Compound 1 is a new glycoside, 3-O-[-L-arabinopyranosyl (1-2)]-L-arabinopyranosyl (l-6)]-2-acetoamido-2-deoxy--D-glucopyranosyl oleanolic acid and exhibits moderate antifungal activity against T. mentogrophytes, C. albicans and S. cerevisiae with MIC values of 6.25, 12.5 and 12.5 g/ml respectively. 相似文献
83.
Nicola J Jordan Malcolm L Watson Robert J Williams Alan G Roach Teizo Yoshimura John Westwick 《British journal of pharmacology》1997,122(4):749-757
- The production of chemokines by vascular smooth muscle cells (SMC) is implicated in the pathogenesis of atherosclerosis, although the factors regulating chemokine production by these cells are incompletely characterized.
- We describe the differential stimulation of interleukin-(IL)-8, monocyte chemoattractant protein (MCP)-1 and regulated on activation normal T-cell expressed and secreted (RANTES) synthesis following treatment of human vascular SMC with IL-1α or tumour necrosis factor α (TNFα). Under basal conditions, cultured SMC release very low amounts of IL-8, MCP-1 and RANTES as assessed by specific ELISA. Concentration-response studies with IL-1α or TNFα revealed that each stimulus induced a similar amount of MCP-1. In contrast approximately three fold more IL-8 was induced by IL-1α than by TNFα whereas significant RANTES production was induced only by TNFα. These findings point to a divergence in the regulation of synthesis of the different chemokines in response to IL-1α or TNFα stimulation.
- The T-cell derived cytokines IL-10 and IL-13 were also found to have differential effects on chemokine production by SMC. IL-13, but not IL-10, significantly enhanced IL-8 and MCP-1 release in response to IL-1α or TNFα. This increase in chemokine release appeared to be accounted for by increased mRNA expression.
- These findings provide support for the concept that smooth muscle cells can have an active role in a local immune response via the production of chemokines which can be selectively modulated by T-cell derived cytokines.
84.
Chromosome 11q13 markers and D-type cyclins in breast cancer 总被引:7,自引:0,他引:7
Gordon Peters Vera Fantl Rosalind Smith Sharon Brookes Clive Dickson 《Breast cancer research and treatment》1995,33(2):125-135
Summary One in six primary human breast cancers has DNA amplification centered on the cyclin D1 gene (CCND1) on chromosome 11q13. This genetic abnormality is preferentially associated with estrogen-receptor positive tumors and may define a sub-class of patients with an adverse prognosis. AlthoughCCND1 has the credentials of a cellular oncogene, being a target for chromosomal translocation and retroviral integration, the 11q13 amplicon encompasses several other markers andCCND1 is not the only candidate for the key gene on the amplified DNA. To assess their relative importance, we have constructed a physical map of the amplified DNA and compared the extent and frequency of amplification across the region. Since it is likely that the gene providing the selective force for amplification will be expressed at elevated levels, we have also examined expression of both RNA and protein. By these criteria, cyclin D1 remains the strongest candidate for the key oncogene on the amplicon and we are currently investigating the functional consequences of its over-expression.Presented by Gordon Peters at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer. 相似文献
85.
C. Pestoni M. V. Lareu M. S. Rodríguez I. Muñoz F. Barros A. Carracedo 《International journal of legal medicine》1995,107(6):283-290
The 5 tetranucleotide short tandem repeats, HUMTHOI, HUMVWA31/A, HUMF13A1, HUMFES/FPS and HUMLPL were studied using different electrophoretic methods and PCR amplification conditions in order to optimize the typing conditions. A genetic population study in the population of Galicia was carried out and the allele and genotype frequencies are given. Compliance with the Hardy-Weinberg equilibrium was tested using different statistical parameters, with clear advantages resulting in favor of using the exact test (Guo-Thompson method) instead of conventional chi-square methods. Some statistical parameters of forensic interest (PD, CE, h) were also calculated. There were no mutations found in a total of 73 paternal meioses and 101 maternal meioses. Abnormal electrophoretic mobility was found in the AT-rich STR HUMF13AI under non-denaturing conditions and, therefore, the use of denaturing conditions is absolutely necessary. No "stutter" bands were found, although double peaks in the HUMFES/FPS system were observed in some samples. The advantage of using automated sequencers with fluorescent technology is also reported. 相似文献
86.
云南拉祜族六个基因座的遗传多态性研究 总被引:3,自引:0,他引:3
目的:了解云南拉祜族6 个短串联重复序列基因座遗传多态性分布。方法:应用复合扩增技术对CSF1PO、TPOX、TH01 、F13A01、FESFPS和vWA等6 个STR基因座进行分析,采用高分辨率的聚丙烯酰胺凝胶电泳分离、银染法显影技术,对云南拉祜族上述6 个STR基因座进行遗传多态性调查。结果:CSF1PO基因座,观察到8 个等位基因,20 个基因型;TPOX 基因座,观察到5 个等位基因,14 个基因型;TH01 基因座,观察到6 个等位基因,17 个基因型;F13A01 基因座,观察到6 个等位基因,13 个基因型;FESFPS基因座,观察到7 个等位基因,15 个基因型;vWA基因座,观察到7 个等位基因,17 个基因型。结论:上述6 个短串联重复序列基因座基因频率分布与Hardy Weinberg 平衡吻合良好。 相似文献
87.
T. Reybrouck A. Amery R. Fagard L. Billiet 《European journal of clinical pharmacology》1977,12(5):333-339
Summary The effect of chronic beta blockade on the haemodynamic response to graded exercise was studied in 18 hypertensive patients treated with bunitrolol, which has partial agonist activity. The patients first received a placebo for 5 to 12 days, then bunitrolol 30 mg daily for one week and subsequently the dose was doubled weekly as necessary upto 240 mg daily. At rest haemodynamic changes after beta blockade were only minor; heart rate decreased by 8% and no significant change was observed in stroke index, cardiac index, (a-v)O2 difference and VO2. The hypotensive effect was not significant and no significant change in mean pulmonary arterial and wedge pressure was observed. Maximal exercise capacity remained unchanged, because of haemodynamic responses. The maximal exercise heart rate was reduced by 25% during beta blockade, which was compensated by a 34% elevation in stroke index, whereas maximal cardiac index and (a-v)O2 difference remained unchanged. There was no consistent change in mean pulmonary artery pressure during maximal exercise, but the mean brachial artery pressure fell by 12%. 相似文献
88.
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
89.
T.W.‐M. Fan A.N. Lane E. Chekmenev R.J. Wittebort R.M. Higashi 《Chemical biology & drug design》2004,63(3):253-264
Abstract: Soil humic substances (HS) are heterologous, polydispersive, and multi‐functional organometallic macromolecules ubiquitous in soils and sediments. They are key players in the maintenance of the belowground ecosystems and in the bioavailability of both organic and inorganic contaminants. It is widely assumed that the peptidic substructures of HS are readily degraded and therefore do not contribute significantly to interactions with contaminants such as toxic metals. To investigate the turnover of humified peptides, laboratory soil aging experiments were conducted with 13C‐glucose or 15N‐nitrate for 8.5 months. Evidence for random‐coil peptidic structures in the labeled HS was obtained from 2‐D nuclear magnetic resonance (NMR), pyrolysis gas chromatography‐mass spectrometry (pyro‐GC‐MS), and circular dichroism data. Interaction of metals with the peptidic carbonyls of labeled HS was rationalized from the solid‐state NMR data. Detailed 13C and 15N labeling patterns of amino acid residues in the acid hydrolysates of HS acquired from NMR and GC‐MS revealed two pools of peptides, i.e. one extant (unlabeled) and the other, newly humified with little isotopic scrambling (fully labeled). The persistence of pre‐existing peptidic structures indicates their resistance to degradation while the presence of fully labeled peptidic amino acids suggests wholesale incorporation of newly synthesized peptides into HS. These findings are contrary to the general notion that humified peptides are readily degraded. 相似文献
90.
雷公藤多甙对狼疮性肾炎患者血浆IL-13含量的影响 总被引:5,自引:0,他引:5
目的 探讨雷公藤多甙 (TW )对狼疮性肾炎 (LN)患者血浆白介素 - 13(IL - 13)含量的影响及治疗价值。方法 分别将激素诱导缓解治疗后的LN患者 ,按其活动指标分为活动期和非活动期 2组 ,活动期患者加用TW治疗 ,观察治疗 3个月后血浆IL - 13水平的变化和肾炎的缓解情况。结果 血浆IL - 13水平明显下降 ,尿蛋白减少 ,狼疮活动性免疫指标、血尿和肾功能改善。结论 TW可抑制血浆IL - 13的产生 ,对控制LN的活动有一定的治疗价值。 相似文献