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61.
Geun-Shik Lee Hoe-Jin Kim Yong-Woo Jung Kyung-Chul Choi Eui-Bae Jeung 《Toxicological sciences》2005,84(2):270-277
It has been demonstrated in our previous studies that Calbindin-D9k (CaBP-9k) is a potent biomarker for screening estrogen-like chemicals in the rat model. Although treatments with 17beta-estradiol (E2) and endocrine disrupting compounds resulted in the up-regulation of uterine CaBP-9k, the mechanism of CaBP-9k induction by these compounds through two subtypes of estrogen receptors (ERalpha and ERbeta) is unclear. Thus, in the present study, immature rats were treated with propyl pyrazole triol (PPT, an ERalpha-selective ligand), diarylpropionitrile (DPN, an ERbeta-selective ligand), E2, or dimethyl sulfoxide (DMSO, a vehicle control) for three days in order to clarify which subtype of ER is involved in the uterine CaBP-9k induction. Following injection with these ER ligands, uterine CaBP-9k expression was analyzed by Northern blot and immunoblot assays. Uterine CaBP-9k expression is mainly mediated by PPT in a dose- and time-dependent manner in immature rats, whereas no significant alteration of the uterine CaBP-9k gene was observed after DPN treatment. In addition, an estrogenicity of PPT in inducing CaBP-9k expression was completely blocked by the anti-estrogen ICI 182,780, implying that uterine CaBP-9k is solely induced by ERalpha. A single treatment with PPT rapidly increased the protein levels of ERalpha and PR, an E2-mediated gene, in these tissues. Taken together, these results indicate that uterine CaBP-9k is induced by E2 and endocrine disrupting chemicals via the ERalpha pathway, but not ERbeta, in the uterus of immature rats. 相似文献
62.
63.
三级医院病人就诊流向探讨 总被引:4,自引:0,他引:4
研究通过对包括专科医院在内的多家三级医院住院病人资料的分析,将疾病种类按ICD-9编码分为19类,研究各类疾病应往低级别医院分流的比例。结果表明:各大类疾病的分流比例不同,分流比例较高的主要是常见病和多发病,总的分流比大约在60%左右。 相似文献
64.
目的:研究无精子症和严重少精子症患者染色体畸变及Y染色体(Yql1区)无精子症因子(azoospermic factor,AZF)缺失情况,建立Y染色体微缺失的临床筛查方法。方法:对134例患者(无精子症97例,严重少精子症37例)经染色体核型分析及AZF、区三个位点8对引物PCR扩增,检测染色体畸变和Y染色体微缺失率。结果:134例中染色体核型异常9例,占6.72%。AZF缺失18例,缺失率为13.43%。无精子症和严重少精子症AZF、缺失率分别为14.43%、10.81%。结论:染色体畸变和Y染色体微缺失是导致无精子症和严重少精子症的主要原因之一。无精子症缺失率高于严重少精子症患者。AZF区三个位点8对引物PCR扩增可作为Y染色体微缺失的临床筛查方法。 相似文献
65.
尿激酶溶栓对大鼠局灶性脑缺血基质金属蛋白酶-9表达的影响 总被引:1,自引:1,他引:0
目的研究大鼠局灶性脑缺血后应用尿激酶(urokinase,UK)溶栓对基质金属蛋白酶-9(Matrix metalloproteinase-9,MMP-9)表达的影响,探讨MMP-9在UK溶栓引起的再灌注损伤及出血性转化中的作用。方法将实验动物随机分成3组进行研究(1)UK溶栓组;(2)缺血对照组;(3)假手术组。分别用免疫组织化学方法分析3组缺血后24hMMP-9的表达,对比研究两组MMP-9表达的差异性。结果缺血后24h前两组均有MMP-9的表达,但是UK溶栓组表达的程度明显高于缺血对照组;假手术组无MMP-9的表达。结论(1)缺血能导致MMP- 9的表达。(2)UK溶栓引起MMP-9表达的上调。 相似文献
66.
T-cell infiltration was detected by immunohistochemistry in only 2 of 10 sural nerve biopsies from patients with Guillain-Barré syndrome (GBS). The number of endoneurial macrophages, identified by the monoclonal antibody MAC 387, was increased, compared with the number in 10 cases of axonal neuropathy. Macrophage-associated demyelination was identified in 7 and axonal degeneration in 8 cases. Cytomegalovirus (CMV) genome was not detected with the polymerase chain reaction. 相似文献
67.
StudyontheRelationshipbetweenCytogeneticsandPhenotypicEffectinTurner'sSyndromeHUXiaofeng(胡晓峰);ZHUBaosheng(朱宝生);LINHanhua(林汉华)... 相似文献
68.
A deficiency of total energy or of one or more essential nutrients, including vitamins A, B6, B12, C, and E, folic acid, zinc, iron, copper, selenium, essential amino acids and essential fatty acids, will impair immune function and increase susceptibility of the host to infectious pathogens. This is most likely because these nutrients are involved in the molecular and cellular responses to challenge of the immune system. Providing these nutrients to deficient individuals restores immune function and improves resistance to infection. Thus, appropriate nutrition is required in order for the host to maintain adequate immune defences towards bacteria, viruses, fungi, parasites and tumour celîs. Although the intakes of several nutrients which result in greatest enhancement of immune function appear to be greater than recommended intakes, excess intake of certain nutrients also impairs immune responses. Some nutrients (e.g. glutamine, arginine) may become limiting in critical illness and there is mounting evidence that provision of these will aid patient recovery. 相似文献
69.
Gerlof D. Valk Arnoud C. Kappelle Aimée M. L. Tjon-A-Tsien Bert Bravenboer Karel Bakker Robert P. J. Michels Cees M. Groenhout Frederik W. Bertelsmann 《Journal of neurology》1996,243(3):257-263
The efficacy of the neurotrophic peptide ORG 2766 in diabetic patients with polyneuropathy was evaluated in a double-blind, placebo-controlled, multicentre trial. One hundred and twenty four patients were randomised in five groups to receive 0.1, 0.4, 2 or 5 mg ORG 2766 or placebo, once daily, administered subcutaneously 52 weeks. Thermal discrimination thresholds (TDT) and vibration perception thresholds (VPT), motor and sensory nerve conduction velocity, Hoffmann reflex, heart rate variation during deep breathing and heart rate response after standing up, neurological examination score and neuropathic symptom score were determined at baseline and after 17, 34 and 52 weeks of treatment. Of the nerve function indices studied, at week 52 the TDTwarmth of the hand in the ORG 2766 0.1, 0.4 and 5 mg groups and the TDTcold of the foot in the ORG 2766 0.1 and 0.4 mg groups significantly improved compared with placebo. Further significant improvement as compared with placebo was observed in the paraesthesia score at week 34 and week 52 in the ORG 2766 2 mg group. Only at week 34 had both the heartbeat variation during deep breathing and the VPT of the foot in the ORG 2766 0.1 mg group improved significantly, compared with placebo. No further statistically significant differences were observed at time for the other measures. No adverse reactions were observed. The only recorded drug-induced side effect was pain at the injection site. Taking all measures of efficacy into account, the statistically significant results observed did not show consistency within each measure. Therefore, it is concluded that ORG 2766, in contrast to earlier reports, is not effective in treating diabetic polyneuropathy. 相似文献
70.
Molecular identification of a small supernumerary marker chromosome by in situ hybridization: diagnosis of an isochromosome 18p with probe L1.84 总被引:1,自引:0,他引:1
A dysmorphic child was found by cytogenetic analysis to have an extra small marker chromosome. The marker chromosome was shown to possess a chromosome 18 centromere by in situ hybridization, and probably represents an isochromosome 18p. Centromere specific probes should be of value in identifying extra small marker chromosomes, and thereby provide better understanding of the clinical significance of these. 相似文献