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排序方式: 共有689条查询结果,搜索用时 15 毫秒
1.
目的:研究CD10蛋白在结直肠癌组织中的表达及其与结直肠癌的各临床病理指标之间的关系,探讨其在结直肠癌发生、发展中的作用。方法:收集78例结直肠癌组织标本及22例癌旁正常组织样本,运用免疫组化EliVision法检测CD10蛋白的表达,并采用卡方检验分析其表达强度及分布比例与结直肠癌临床病理指标的关系。结果:CD10蛋白在结直肠癌组织和正常结肠黏膜组织中的阳性表达率分别为46.2%(36/78)和0,差异有统计学意义(P < 0.01)。结直肠癌组织中CD10蛋白表达比例与各临床病理指标均无明显相关(P > 0.05)。结直肠癌组织中CD10蛋白表达强度与患者性别、年龄、肿瘤部位、分化程度、浸润深度无明显相关(P > 0.05),而与肿瘤的临床分期、有无脉管侵犯及淋巴结转移有关(P < 0.05),中晚期结直肠癌CD10蛋白表达强度高于早期肿瘤(P=0.033),周围淋巴结转移阳性的结直肠癌CD10蛋白表达强度高于淋巴结阴性病例(P=0.023),存在脉管受侵犯的结直肠癌CD10蛋白表达强度高于无脉管受侵病例(P=0.004)。结论:CD10蛋白在结直肠癌组织中呈高表达,且表达强度与肿瘤的临床分期、有无脉管侵犯及淋巴结转移有关,可能有促进结直肠癌发展和浸润转移的作用。  相似文献   
2.
Microsurgical vasoepididymostomy (MVE) is recommended as a first‐line option for treatment of epididymal obstructive azoospermia (EOA). However, early indicators for predicting patency and natural pregnancy are unclear. Our aim was to explore the early predictive value of seminal plasma neutral alpha‐glucosidase (NAG) activity for patency and natural pregnancy after MVE. Eighty‐four patients with EOA who underwent MVE were enrolled in this study. The post‐operative patency and natural pregnancy rates were 60.71% and 33.33% respectively. The presence of motile epididymal spermatozoa at the anastomosis site and NAG activity measured at the first month after MVE were early and independent predictors of patency and natural pregnancy. The areas under the receiver operating characteristic curves (AUCs) of NAG activity for prediction of patency and natural pregnancy were 0.78 (95% confidence interval [CI]: 0.68–0.88) and 0.82 (95% CI: 0.73–0.92). The best cut‐off values of NAG activity for predicting patency and pregnancy were 15.9 and 17.0 m IU/ejaculate respectively. In conclusion, NAG activity measured at the first month after MVE is an early and independent predictor of patency and natural pregnancy.  相似文献   
3.
Perioperative medical management is challenging due to the rising complexity of patients presenting for surgical procedures. A key part of preoperative optimization is appropriate management of long-term medications, yet guidelines and consensus statements for perioperative medication management are lacking. Available resources utilize the recommendations derived from individual studies and do not include a multidisciplinary focus or formal consensus. The Society for Perioperative Assessment and Quality Improvement (SPAQI) identified a lack of authoritative clinical guidance as an opportunity to utilize its multidisciplinary membership to improve evidence-based perioperative care. SPAQI seeks to provide guidance on perioperative medication management that synthesizes available literature with expert consensus. The aim of this Consensus Statement is to provide practical guidance on the preoperative management of endocrine, hormonal, and urologic medications. A panel of experts with anesthesiology, perioperative medicine, hospital medicine, general internal medicine, and medical specialty experience was drawn together and identified the common medications in each of these categories. The authors then utilized a modified Delphi approach to critically review the literature and generate consensus recommendations.  相似文献   
4.
5.
The objective was to develop a laboratory procedure to validate American Urological Association (AUA) Guideline on vasectomy success when nonmotile spermatozoa are found in the post-vasectomy ejaculate. The neutral α-glucosidase (NAG) an epididymal protein assay modified to determine the activity at 30 and 90 min of incubation from 24 pre- and 47 post-vasectomy ejaculates. The difference between the two points in the relative activity was calculated and if the difference was nonsignificant will confirm vasectomy success. The mean differences in the relative NAG activity were significantly different in pre- and post-vasectomy ejaculates, respectively. The mean differences in the relative NAG activity were similar in post-vasectomy ejaculates with and without nonmotile spermatozoa. No difference in relative NAG activity in post-vasectomy ejaculates between two time points of incubation may be a reliable method to confirm occlusion of the vas deferens. It also validates the recommendation by AUA Guideline on vasectomy success in the presence of few nonmotile spermatozoa.  相似文献   
6.
目的:观察乳腺癌细胞系MCF7细胞中,钙激活中性蛋白酶2(calpain-2)对整合素(integrin)β4水解的影响。方法:利用"短发夹"RNA(shRNA)和微小RNA(mirRNA)技术结合的calpain-2基因沉默(gene silencing)慢病毒质粒(GIPZ lentiviral shRNAmir)转染乳腺癌细胞株MCF7,嘌呤霉素筛选稳定沉默calpain-2基因的细胞株,细胞株传4代,用荧光显微镜观察转染效率,用蛋白质印迹(Western blot)实验检测calpain-2基因沉默效率及integrinβ4水解的情况。结果:嘌呤霉素筛选、细胞传4代,荧光显微镜下观察显示转染和筛选后,EGFP表达阳性的MCF7细胞的比例分别达到(95.6±2.6)%(空shRNAmir载体)、(97.1±1.7)%(Calpain-2 shRNAmir1)和(97.7±0.2)%(Calpain-2 shRNAmir 2),差异无统计学意义(P>0.05);Western blot结果显示,基因沉默的MCF7细胞中calpain-2的表达被明显抑制,相对于空shRNAmir载体转染的MCF7细胞,差异有统计学意义(P<0.01),calpain-2的表达下调到21.5%(Calpain-2 shRNAmir 1)和18.8%(Calpain-2 shRNAmir 2),空shRNAmir载体转染的MCF7细胞中calpain-2的表达与未转染的MCF7细胞比较,差异无统计学意义(P>0.05);比较calpain-2基因沉默和空shRNAmir载体转染的MCF7细胞,发现integrinβ4均被水解,水解片段的分子量主要有200 k D、130和95 k D;calpain-2基因沉默后,calpain-2基因沉默MCF7细胞中200 k D的水解片段比空shRNAmir载体转染的MCF7细胞减少(P<0.01)。结论:在乳腺癌细胞MCF7中,calpain-2可能参与integrinβ4的200 k D片段的形成,从而参与调整integrinβ4的构象变化。  相似文献   
7.
Aflatoxins, a group of extremely toxic mycotoxins produced by Aspergillus flavus, A. parasiticus and A. nomius, can occur as natural contaminants of certain agricultural commodities, particularly maize. These toxins have been shown to be hepatotoxic, carcinogenic, mutagenic and cause severe human and animal diseases. The effectiveness of neutral electrolyzed oxidizing water (NEW) on aflatoxin detoxification was investigated in HepG2 cells using several validation methodologies such as the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, the induction of lipid peroxidation, the oxidative damage by means of glutathione modulation, the Ames test and the alkaline Comet assay. Our results showed that, after the aflatoxin-contaminated maize containing 360 ng/g was soaked in NEW (60 mg/L available chlorine, pH 7.01) during 15 min at room temperature, the aflatoxin content did not decrease as confirmed by the immunoaffinity column and ultra performance liquid chromatography methods. Aflatoxin fluorescence strength of detoxified samples was similar to untreated samples. However, aflatoxin-associated cytotoxicity and genotoxicity effects were markedly reduced upon treatment. According to these results, NEW can be effectively used to detoxify aflatoxin-contaminated maize.  相似文献   
8.
Cypermethrin is a synthetic pyrethroid insecticide used worldwide in agriculture, home pest control, disease vector control, and food safety. It accumulates in soil. Therefore, traces of cypermethrin may frequently appear in vegetables grown in contaminated soil. There is a push now to develop biomarkers as early warning indicators of environmental pollution. In this study, DNA damage (tail DNA%, tail length, and olive tail moment), the micronucleus, neutral red retention (NRR) time, and pinocytic adherence ability of coelomocytes were investigated in Pheretima peguana earthworms exposed to cypermethrin in filter paper tests. The NRR time of earthworm coelomocytes decreased significantly at a concentration of 3.5 × 10?3 µg · cm?2 (1/100 LC50) after 48 h exposure, with a highly negative correlation with cypermethrin concentration. Pinocytic adherence ability of coelomocytes also declined significantly at a cypermethrin concentration of 3.5 × 10?2 µg · cm?2 (1/10 LC50). The DNA damage to earthworm coelomocytes (tail DNA%, tail length, and olive tail moment) increased considerably at the highest concentration (3.5 × 10?1 µg · cm?2) although the correlation between tail DNA% and cypermethrin concentration was low. Thus, physiological biomarkers were more sensitive than the genotoxic effects in earthworms exposed to commercial cypermethrin. Although a suite of earthworm biomarkers could be used to evaluate cypermethrin terrestrial pollution, the NRR test is easier to conduct and a more sensitive indicator. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 597–606, 2015.  相似文献   
9.
Summary Rats with streptozotocin-induced chronic diabetes mellitus develop a glomerulopathy functionally manifested by proteinuria. The ability of the glomerular capillary wall to retard filtration of macromolecules was examined in 5 chronically diabetic Munich-Wistar rats exhibiting excessive proteinuria (39±7mg/24h, mean±SEM) and 5 age-matched normal Munich-Wistar rats without increased proteinuria (4.7±0.2 mg/24 h). Urinary albumin excretion was not increased in the diabetic rats (2.0±0.6 mg/24h vs 1.6±0.3 mg/24h) suggesting that the normal net electronegative charge of the glomerular capillary wall was not altered. Fractional clearances of macromolecular neutral dextrans were similar in diabetic and normal rats throughout a wide range of molecular size (18–42 Å). Glomerular filtration rate was the same in the two groups of rats (2.77±0.16ml/min in diabetics and 2.72±0.11ml/ min in normals) suggesting that renal haemodynamic factors did not influence fractional clearances of neutral dextrans in diabetic rats. We conclude that the proteinuria exhibited by these chronically diabetic rats is not attributable to alterations of size-selective properties of the glomerular capillary wall, such as increases in the size or the number of pores.  相似文献   
10.
To study the effect of ammonia administration on amino acids and indoleamines in cerebrospinal fluid (CSF) and on amino acids, insulin, and glucagon in plasma in humans with liver cirrhosis, we performed seven ammonia tolerance tests on six patients with stable liver cirrhosis. The grade of encephalopathy was determined by psychometric tests. Only one of the patients had pronounced encephalopathy. The other patients had no or only slight encephalopathy. The plasma concentrations of valine, leucine, isoleucine, phenylalanine, tyrosine, and methionine decreased after the ammonia load, whereas no changes were found in the plasma concentrations of glucagon and insulin. In CSF the concentrations of glutamine, aromatic amino acids, and indoleamines increased only in the patient who had pronounced encephalopathy, whereas no changes were found in the other patients. The effect of an ammonia load on the concentrations of neutral amino acids in CSF in patients with pronounced encephalopathy remains to be demonstrated.  相似文献   
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