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51.
Anthonie J. van Essen Coen J. F. Schoots Richard A. van Lingen Marian J. E. Mourits Joep H. A. M. Tuerlings Bieke Leegte 《American journal of medical genetics. Part A》1993,47(1):85-88
We report on the clinical and pathologic findings in a girl with isochromosome 18q (46, XX,i(18q)) who had combined manifestations of monosomy 18p and trisomy 18q. Major congenital anomalies included premaxillary agenesis, alobar holoprosenphaly, double Outlet right ventricle, DiGeorge anomaly and streak ovaries. The clinical spectrum in i(18q) is very broad. © 1993 Wiley-Liss, Inc. 相似文献
52.
Régine Ramdine Anne-Marie Galzin Salomon Z. Langer 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(4):386-395
Summary In superfused rat hypothalamic slices prelabelled with [3H]-noradrenaline, the 2-adrenoceptor agonist UK 14304 inhibited in a concentration-dependent manner the electrically-evoked release of tritium. This inhibition was antagonized by the 2-adrenoceptor blocking agent idazoxan, which by itself increased the electrically-evoked tritium overflow. Exposure to forskolin, an adenylate cyclase activator, increased the electrically-evoked release of [3H]-noradrenaline. In the presence of forskolin (1 mol/l), both the inhibitory effect of UK 14304 and the increasing effect of idazoxan on the electrically-evoked release of [3H]-noradrenaline were less pronounced than in the absence of the adenylate cyclase activator. Exposure to forskolin and to the phosphodiesterase inhibitor 3-isobutyl-l-methylxanthine shifted to the right the concentration-effect curve for UK 14304 in a similar manner as that observed in the presence of forskolin alone. Exposure to phorbol-12,13-dibutyrate (0.01–10 mol/l), a drug which activates protein kinase C, increased the electrically-evoked release of [3H]-noradrenaline. In the presence of phorbol-12,13-dibutyrate (0.1 and 1 mol/l), the concentration effect curve for UK 14304 on tritium overflow was significantly shifted to the right. The increasing effect of idazoxan on tritium overflow was significantly less pronounced in the presence of 1 mol/l phorbol-12,13-dibutyrate.In superfused rat hypothalamic slices prelabelled with [3H]-5-hydroxytryptamine, the 2-adrenoceptor agonist UK 14304 significantly inhibited the electrically-evoked release of tritium. Exposure to forskolin increased in a concentration-dependent manner [3H]-5-hydroxytryptamine overflow, but did not modify the UK 14304-mediated inhibition. Exposure to 3-isobutyl-1-methylxanthine enhanced the electrically-evoked release of [3H]-5-hydroxytryptamine. In the presence of both forskolin (1 mol/l) and 3-isobutyl-l-methylxanthine (1 mmol/l), the concentration-response curve for UK 14304 was significantly shifted to the right. Exposure to phorbol-12,13-dibutyrate (0.01–10 mol/l) enhanced in a concentration-dependent manner the electrically-evoked overflow of [3H]-5-hydroxytryptamine. In the presence of phorbol-12,13-dibutyrate (0.1 and 1 mol/l), UK 14304 was significantly less potent to inhibit tritium release than in the absence of the protein kinase C activator.It is concluded that both cyclic AMP and phosphoinositide turnover are involved in the modulation of noradrenaline and 5-hydroxytryptamine release by presynaptic 2-adrenoceptors in rat hypothalamic slices. However, these interactions do not represent definitive proof for a cause-effect relationship for the second messengers mediating the 2-adrenoceptor induced inhibition of transmitter release either as autoreceptor or as heteroreceptor.Send offprint requests to S. Z. Langer at the above address 相似文献
53.
《Immunity》2020,52(6):1075-1087.e8
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54.
目的观察双重组RGD肽水蛭素对大鼠冠脉微循环障碍的疗效 ,并探讨其作用机理。方法健康雄性SD大鼠共62只 ,随机分为正常对照组 (n=6)、安慰剂组 (n=18)以及RGD肽水蛭素治疗组(n=36) ,后者根据所用RGD肽水蛭素剂量进一步分为1mg/kg和5mg/kg体质量2个亚组 ,每组各18只。RGD肽水蛭素于建模当日采用腹腔注射的方法给药 ,以注射生理盐水做为安慰剂。分别采用病理切片、超声心动图和彩色微粒子测量技术 ,观察各组大鼠心肌内微血栓和微梗死形成 ,以及心功能和心肌局部血流量变化的情况 ;采用免疫组化和RT -PCR的方法观察心肌组织内IL -18蛋白及mRNA的表达。结果与安慰剂组相比 ,1mg/kg/d及5mg/kg/d的RGD肽水蛭素可显著减少大鼠心肌内微栓塞数量以及局部梗死面积 (P<0.01) ,同时大鼠心功能LVEF和心肌局部血流量也明显得到改善 ;RGD肽水蛭素也显著下调大鼠心肌组织内IL -18蛋白和mRNA的表达 (P<0.05)。结论RGD肽水蛭素能明显改善大鼠因微栓塞所致的冠脉微循环障碍 ,可作为治疗冠脉微循环障碍的重要药物。其中抑制IL -18的分泌表达 ,可能是RGD肽水蛭素抗炎改善冠脉微循环的重要机制之一。 相似文献
55.
Decreased prefrontal 5-HT2A receptor binding in subjects at enhanced risk for schizophrenia 总被引:4,自引:0,他引:4
Hurlemann R Boy C Meyer PT Scherk H Wagner M Herzog H Coenen HH Vogeley K Falkai P Zilles K Maier W Bauer A 《Anatomy and embryology》2005,210(5-6):519-523
The brain serotonin-2A receptor (5-HT2AR) has been implicated in both the pathology of schizophrenia and the therapeutic action of atypical antipsychotics. However,
little is known about the 5-HT2AR status before the onset of schizophrenia and before the exposure to antipsychotics. We used [18F] altanserin and positron emission tomography (PET) in a pilot study of 6 individuals suspected to be at elevated risk for
schizophrenia and seven age-matched controls to test the hypothesis that regional 5-HT2AR binding is altered in the prodromal stages of schizophrenia. Distribution volume ratios (DVRs) as a proxy for 5-HT2AR availability were significantly reduced in prefrontal cortex regions of at-risk subjects, implicating early abnormalities
of serotonergic neurotransmission that antecede the onset of schizophrenia. 相似文献
56.
Krásná E Kolesár L Slavcev A Valhová S Kronosová B Jaresová M Stríz I 《Inflammation》2005,29(1):33-37
IL-18 is a multifunctional cytokine that augments both innate and acquired immunity and potentiates Th1 and Th2 reactions.
We studied the expression of IL-18 receptor (IL-18R) on renal and respiratory epithelial cell lines. Both cell lines upregulated
IL-18R mRNA and IL-18R membrane expression in response to TNF alpha and other proinflammatory cytokines. The function of IL-18R
was confirmed by induction of IL-8 release from epithelial cells in response to recombinant IL-18. Epithelial cells may represent
an important target for IL-18, mainly under inflammatory conditions associated with TNF alpha release. 相似文献
57.
58.
59.
PET/CT在肿瘤疾病中的初步应用 总被引:2,自引:0,他引:2
目的回顾性探讨PET/CT对肿瘤的诊断价值。方法肿瘤病人200例,其中未治疗病人71例,已治疗病人129例。经静脉注射^18F-FDG 45min后,进行PET/CT扫描。结果未治疗病人71例中,PET/CT准确诊断有68例(95.7%),阴性3例,发现肿瘤转移54例,其中广泛转移30例。已治疗组129例中,提示肿瘤复发或/伴转移96例,其余33例在手术/放疗/化疗等治疗后未见肿瘤复发。结论PET/CT具有对病变部位进行精确定位和定性的优势,大大提高了诊断的准确率。对于肿瘤的早期诊断和分期、指导制定治疗方案、判断肿瘤有无复发与坏死及预后的估计均有重要的临床意义。 相似文献
60.
牛IL-18基因的克隆及遗传进化分析 总被引:3,自引:0,他引:3
目的:克隆牛白细胞介素18(IL-18)全基因,并对其进行序列分析。方法:从ConA刺激培养的牛外周血淋巴细胞提取总RNA,利用巢式RT-PCR方法扩增出牛IL-18全长cDNA,将其克隆到pMDl8-T载体上,测序后进行序列分析。结果:成功地克隆到了牛IL-18全基因,序列分析表明,实验中所克隆到的牛IL-18序列与GeneBank所登录的牛IL-18核苷酸序列及其推导氨酸序列同源性分别是99.5%和99%。与人、猕猴、野猪、山羊属、马等核苷酸序列及其推导氨基酸序列同源性分别在84.9%-99.5%和74.9%~99%之间,研究结果在国内还未见报道。结论:成功地从牛外周血中克隆到了牛IL-18的基因,其全长为598bp。 相似文献