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Excess NO generation plays a major role in the hypotension and systemic vasodilatation characteristic of sepsis. Yet the kidney response to sepsis is characterized by vasoconstriction resulting in renal dysfunction. We have examined the roles of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) on the renal effects of lipopolysaccharide administration by comparing the effects of specific iNOS inhibition, -N6-(1-iminoethyl)lysine (L-NIL), and 2,4-diamino6-hydroxy-pyrimidine vs. nonspecific NOS inhibitors (nitro- -arginine-methylester). cGMP responses to carbamylcholine (CCh) (stimulated, basal) and sodium nitroprusside in isolated glomeruli were used as indices of eNOS and guanylate cyclase (GC) activity, respectively. LPS significantly decreased blood pressure and GFR (112+/-4 vs. 83+/-4 mmHg; 2.66+/-0.29 vs. 0. 96+/-0.22 ml/min, P < 0.05) and inhibited the cGMP response to CCh. GC activity was reciprocally increased. L-NIL and 2, 4-diamino-6-hydroxy-pyrimidine administration prevented the decrease in GFR (2.71+/-0.28 and 3.16+/-0.18 ml/min, respectively), restored the normal response to CCh, and GC activity was normalized. In vitro application of L-NIL also restored CCh responses in LPS glomeruli. Neuronal NOS inhibitors verified that CCh responses reflected eNOS activity. L-NAME, a nonspecific inhibitor, worsened GFR (0.41+/-0.15 ml/min), a reduction that was functional and not related to glomerular thrombosis, and eliminated the CCh response. No differences were observed in eNOS mRNA expression among the experimental groups. Selective iNOS inhibition prevents reductions in GFR, whereas nonselective inhibition of NOS further decreases GFR. These findings suggest that the decrease in GFR after LPS is due to local inhibition of eNOS by iNOS, possibly via NO autoinhibition.  相似文献   
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Quality of Life Research - To identify and evaluate methods for assessing pediatric patient-reported outcome (PRO) data quality at the individual level. We conducted a systematic literature review...  相似文献   
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Hepatoid adenocarcinoma of the stomach is an uncommon subtype of gastric cancer remarkably similar to hepatocellular carcinoma in histopathological analysis. It is also commonly associated with high serum alfa-fetoprotein and a poorer prognosis, despite the emergence of new therapeutic options. In recent years, next generation sequencing (NGS) technology has made it possible to identify and describe the genes and molecular alterations common to gastric cancer thereby contributing to the advancement of targeted therapies. A 62-year-old patient, with no prior risk factor for hepatocellular carcinoma (HCC), presented to the emergency room with dysphagia for solids, abdominal pain and weight loss of about 3 kilograms over 3 months. Histopathological analysis presented with disparities regarding HER2 and programmed death-ligand 1 (PD-L1) status in the primary and metastatic sites. We describe a case of a de novo metastatic, human epidermal growth factor receptor 2 (HER2) positive esophagogastric junction hepatoid adenocarcinoma. Although this is a rare subgroup of gastric cancer, treatment strategies were based in recent studies in immunotherapy and guided therapy, taking into consideration the molecular findings from the patient’s tumor NGS analysis. Data about HER2 and PDL1 heterogeneity were also reviewed. Despite the aggressiveness and rarity of this histology, the patient had a good response to treatment.  相似文献   
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王晓华  闫冰冰 《医学争鸣》2005,26(8):723-723
1 临床资料 2000-03/2004-06阴道松弛症女性30例,年龄24~44岁,其中24~30岁12例,占40%;31~40岁10例,占33.3%;41~44岁8例,占26.7%.术前检查阴道容三指以上,自诉因阴道松弛性生活时快感不足,均排除子宫脱垂、阴道炎及阴道肿瘤等疾病.手术在月经完全干净3 d后,采用硬膜外麻醉或局部麻醉下进行.患者取膀胱截石位,于阴道口外6点处设计出一弧形切口,左右宽度3~7 cm具体视阴道松弛程度而定,沿设计线在阴道黏膜下注射盐酸肾上腺素盐水以利止血和分离,切开并剥离阴道后壁黏膜,暴露黏膜下肌肉,以可吸收缝线拉拢缝合阴道黏膜下左右侧阴道括约肌及肛提肌等,从阴道深处开始缝合,缝到阴道口附近处.缝合后阴道容二指松.阴道后壁黏膜不切除,阴道黏膜下肌肉左右对叠缝合后阴道黏膜自然向上膨隆形成一皱襞.阴道外的横弧形切口因黏膜下肌肉左右拉拢缝合,变成竖形切口以丝线间断缝合.术后静滴抗生素3 d,每天以碘伏清洗切口1次,7 d拆线,2 mo内禁止性生活.术后随访3~6 mo,自诉性快感明显增强22例,改善8例.  相似文献   
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We have previously localized a cervical cancer tumor suppressor gene to a 300 kb interval of 11q13. Analysis of candidate genes revealed loss of expression of cystatin E/M, a lysosomal cysteine protease inhibitor, in 6 cervical cancer cell lines and 9 of 11 primary cervical tumors. Examination of the three exons in four cervical cancer cell lines, 19 primary tumors, and 21 normal controls revealed homozygous deletion of exon 1 sequences in one tumor. Point mutations were observed in six other tumors. Two tumors contained mutations at the consensus binding sites for cathepsin L, a lysosomal protease overexpressed in cervical cancer. Introduction of these two point mutations using site directed mutagenesis resulted in reduced binding of mutated cystatin E/M to cathepsin L. Although mutations were not observed in any cell lines, four cell lines and 12 of 18 tumors contained promoter hypermethylation. Reexpression of cystatin E/M was observed after 5'aza 2-deoxycytidiene and/or Trichostatin A treatment of cervical cancer cell lines, HeLa and SiHa, confirming promoter hypermethylation. Ectopic expression of cystatin E/M in these two cell lines resulted in growth suppression. There was also suppression of soft agar colony formation by HeLa cells expressing the cystatin E/M gene. Reexpression of cystatin E/M resulted in decreased intracellular and extracellular expression of cathepsin L. Overexpression of cathepsin L resulted in increased cell growth which was inhibited by the reintroduction of cystatin E/M. We conclude, therefore, that cystatin E/M is a cervical cancer suppressor gene and that the gene is inactivated by somatic mutations and promoter hypermethylation.  相似文献   
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