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81.
We describe a case of indolent vascular prosthesis infection due to Propionibacterium acnes. The microorganism was identified only by amplification and sequencing of 16S rDNA, while standard cultures remained negative. This observation underscores the usefulness of molecular techniques for the diagnosis of infection caused by fastidious microorganisms.  相似文献   
82.
Renin- angiotensin system( RAS) candidat-ing gene,such as angiotensinogen( Ag T) as wellas angiotensin- converting enzyme( ACE) genepolymorphism were thought to have positive association with various cardiovasculardiseases.In1 992 ,Jeunemaitre[1] detected a microsatellitepolymorphism in the region of the an-giotensinogen gene which has linked to occur-rence of essential hypertension.Further analysisled to detection of several mutations in the cod-ing region of angiotensinogen gene[2 ] . Ma…  相似文献   
83.
BackgroundPatients undergoing esophagectomy often receive jejunostomy tubes (j-tubes) for nutritional supplementation. We hypothesized that j-tubes are associated with increased post-esophagectomy readmissions.Study designWe identified esophagectomies for malignancy with (EWJ) or without (EWOJ) j-tubes using the 2010–2015 Nationwide Readmissions Database. Outcomes include readmission, inpatient mortality, and complications. Outcomes were compared before and after propensity score matching (PSM).ResultsOf 22,429 patients undergoing esophagectomy, 16,829 (75.0%) received j-tubes. Patients were similar in age and gender but EWJ were more likely to receive chemotherapy (24.2% vs. 15.1%, p < 0.01). EWJ was associated with decreased 180-day inpatient mortality (HR 0.72 [0.52–0.99]) but not with higher readmissions at 30- (15.2% vs. 14.0%, p = 0.16; HR 0.9 [0.77–1.05]) or 180 days (25.2% vs. 24.3%, p = 0.37; HR 0.94 [0.79–1.10]) or increased complications (p = 0.37). These results were confirmed in the PSM cohort.ConclusionJ-tubes placed in the setting of esophagectomy do not increase inpatient readmissions or mortality.  相似文献   
84.
IntroductionThe effectiveness of transanal decompression tube (TDT) to prevent anastomotic leakage after rectal surgery has been widely accepted in recent years. However, a rare complication of intestinal perforation due to TDT has been also reported.Presentation of caseA 88-year-old woman underwent laparoscopic low anterior resection for rectal cancer. An abdominal drainage tube adjacent to the colorectal anastomosis and a TDT were placed. The patient experienced abdominal pain, nausea and elevated inflammatory markers on postoperative day 6. Enema and computed tomography demonstrated colonic perforation due to the TDT, and emergency laparotomy was performed. Perforation of the anterior sigmoid colon located at the proximal side of the colorectal anastomosis was seen, and the TDT was exposed to the abdominal cavity. Therefore, primary closure of the perforation site, peritoneal lavage, drainage tube placement and transverse colostomy was performed.DiscussionIn our case, TDT seemed to compress the anterior wall of the colon and lead to perforation. The looseness of the remaining oral intestinal tract depressed in the pelvis was compressed by the TDT.ConclusionTDTs should be very carefully placed to avoid complication. The length and looseness of the oral intestine and the relationship between the TDT to be inserted might be important.  相似文献   
85.
86.
目的研究喉癌中表皮生长因子受体(EGFR)基因的扩增、表达,探讨其在喉癌发生、发展中的作用及临床意义。方法采用差异PCR(differential PCR)方法检测40例喉鳞状细胞癌及配对癌旁正常组织中EGFR基因的扩增(即基因拷贝数增加);应用RT-PCR方法检测EGFR mRNA水平;应用SPSS13.0软件对数据进行统计学分析。结果喉癌组织中有13例(占32.5%)EGFR基因拷贝数增加,癌旁对照组中则未检测到(χ2=15.537,P<0.005);喉癌组织中EGFR mRNA平均积分光密度为872.356±62.340,癌旁对照组为346.425±57.380(t=5.959,P<0.001);喉癌组织分化程度越低,病理分期越晚,EGFR基因扩增和mRNA表达水平越高(P<0.05)。结论喉癌中EGFR基因在DNA水平上的扩增是EGFR mRNA过表达的原因之一,EGFR的扩增和过表达在喉癌的发生、进展中发挥一定作用。  相似文献   
87.
BACKGROUND: Detection and quantification of adenovirus (ADV) in peripheral blood specimens has become an increasingly important tool in the management of immunosuppressed patients. Investigators have described the use of whole blood (WB), peripheral blood mononuclear cells (PBMC), serum and plasma but no studies have compared the utility of these different sample types for use in a clinical diagnostic assay. OBJECTIVES: To determine the optimal blood compartment for quantitative real-time measurement of adenovirus in peripheral blood specimens. STUDY DESIGN: WB, PBMC, and plasma representing 338 samples from 148 patients were tested for ADV by quantitative real-time PCR (qrt-PCR) and the results compared for concordance of both qualitative sensitivity and viral load among positive specimens. RESULTS: There was no significant difference in qualitative sensitivity among the three tested specimen types. Quantitative values of WB and plasma were similar and tended to be greater than those found in PBMC samples. Comparison of consecutive positive samples within individual patients showed that viral loads tracked similarly over time, irrespective of the sample type tested. CONCLUSION: While WB and plasma do not offer a significant increase in sensitivity over PBMC, they may offer benefits in terms of reduced processing costs and laboratory turn around time.  相似文献   
88.
Summary The contours of pressure and flow of a pulse wave arriving at the entrance of a collapsed segment of an elastic tube can be described by application of the basic laws of reflection. The collapsed segment acts like a valve. It is opened by the pressure of the pulse wave when the pressure within the tube becomes higher than the collapse pressure, i.e. the pressure exerted on the segment from outside. This opening of the collapsed segment suddenly changes the sign of the pulse wave reflection from positive to negative; thus a typical contour change of the pulse proximal to the segment is observed. The most obvious effect is a reduction of the pulse pressure. The extent of this reduction is a function of the collapse pressure.A typical example of this phenomenon can be observed in an artery proximal to the segment which is collapsed due to the pressure exerted by an inflated Riva-Rocci cuff. The effect is explained by the assumption that the sign of reflection changes when the pressure of the pulse wave crosses the level of the cuff pressure. This explanation is supported by the results of model experiments.  相似文献   
89.
孕妇血清标记物在中孕筛查中的应用   总被引:4,自引:0,他引:4  
目的 :通过对孕妇血清标记物甲胎蛋白 (AFP)和人绒毛膜促性腺激素 ( β -HCG )测定来筛选缺陷儿。 方法 :用放射免疫法对 6 2例孕 14~ 2 3周妊娠妇女上述标记物连测 3次 ,每次隔 12~ 14d ,以两次异常为高危个体。每例筛查者跟踪至胎儿出生后。结果 :在筛查中发现了 1例先天愚型和 1例无脑儿。结论 :上述两种血清标记物可以作为神经管缺陷和先天愚型筛查的一项常规方法  相似文献   
90.
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