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BackgroundDamage to the renal microvasculature is a hallmark of renal ischemia-reperfusion injury (IRI)–mediated AKI. The miR-17∼92 miRNA cluster (encoding miR-17, -18a, -19a, -20a, -19b-1, and -92a-1) regulates angiogenesis in multiple settings, but no definitive role in renal endothelium during AKI pathogenesis has been established.MethodsAntibodies bound to magnetic beads were utilized to selectively enrich for renal endothelial cells from mice. Endothelial-specific miR-17∼92 knockout (miR-17∼92endo−/−) mice were generated and given renal IRI. Mice were monitored for the development of AKI using serum chemistries and histology and for renal blood flow using magnetic resonance imaging (MRI) and laser Doppler imaging. Mice were treated with miRNA mimics during renal IRI, and therapeutic efficacies were evaluated.ResultsmiR-17, -18a, -20a, -19b, and pri–miR-17∼92 are dynamically regulated in renal endothelial cells after renal IRI. miR-17∼92endo−/− exacerbates renal IRI in male and female mice. Specifically, miR-17∼92endo−/− promotes renal tubular injury, reduces renal blood flow, promotes microvascular rarefaction, increases renal oxidative stress, and promotes macrophage infiltration to injured kidneys. The potent antiangiogenic factor thrombospondin 1 (TSP1) is highly expressed in renal endothelium in miR-17∼92endo−/− after renal IRI and is a target of miR-18a and miR-19a/b. miR-17∼92 is critical in the angiogenic response after renal IRI, which treatment with miR-18a and miR-19b mimics can mitigate.ConclusionsThese data suggest that endothelial-derived miR-17∼92 stimulates a reparative response in damaged renal vasculature during renal IRI by regulating angiogenic pathways.  相似文献   
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Objective ToinvestigatetheexpressionofmRNAofα1 adrenoceptorinhepatictissuesofcirrhoticpatientswithportalhypertension Methods Semi quantitativereversetranscriptionandpolymerasechainreaction (RT PCR)wereusedin 12hepaticvirusB relatedcirrhoticpatientswithport…  相似文献   
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COMPLICATIONS IN LAPAROSCOPIC GYNECOLOGIC SURGERY   总被引:3,自引:0,他引:3  
Objective. To investigate retrospectively the complications and associated factors of gynecological laparescopies.Methods. 1769 laparoscopic surgeries were carried out from January 1994 to October 1999 at our department. The procedures included 1421 surgeries of ovary and tube, 52 myomectomies and 296 cases of laproscopic-assisted vaginal hysterectomy (LAVH). A total of 312 patients had a history of prior laparotomy (17.6%). Results. Complications occured in 34 cases, the overall complication rate was 1.92%. Unintended laparotomies occured in 6 cases(0.34% ). 12 complications were associated with insertion of Veress needle or trocar and creation of pneumoperitoneum, including 5 severe emphysema and 7 vascular injuries, this figure represents 35.3% of all complications of this series. Five intraopemtive complications (14.7 % ) occured during the laparescopic surgery (3 severe bleedings, one bladder injury and one skin bum of leg caused by damaged electrode plate), laparotomy was re-quired in four of these cases. Seventeen complications occured during postoperative stage: 2 intraperitoneal hemor-rhages needing laparotomy, 2 bowel injuries, 4 nerve paresis and 9 febrile morbidities. Cordusions. Operative gynecologic laparoscopy is associated with acceptable morbidity rate, but can not be over-looked. Complication rate seems to be higher in advanced procedures such as LAVH.  相似文献   
25.
目的:观察4种苍蝇毒饵的灭蝇效果。方法:在0.343m~3的测试柜内观察苍蝇的LT_(50)及24h死亡率。结果:蝇蟑宁和韩1号毒饵的半数死时间最短,分别为1.10和1.79h,24h死亡率最高分别为98.43%和91.41%,两者差异无显著性。结论:蝇蟑宁毒饵灭效最好,具有推广应用价值。  相似文献   
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The clinical urologist often is faced with the referral of a patient with urinary incontinence refractory to conservative measures. Given the broad spectrum of causes of urinary incontinence, the clinician must base evaluation and therapeutic management on current principles of urinary tract pathophysiology. This article organizes the pertinent diagnostic considerations that must be addressed in guiding the clinician to the appropriate surgical treatment option.  相似文献   
28.
结肠、直肠癌术前区域动脉灌注化疗的临床病理观察   总被引:32,自引:1,他引:31  
Gu J  Ma Z  Ye Y  Xue W  Qu J  Zhao Y  Yu Y  Leng X  Zhu X 《中华外科杂志》1999,37(6):333-335,I021
目的 探讨结直肠癌术前区域动脉灌注化疗对临床病理特征的影响及其可行性。方法 对30例结、直肠癌患者以Seldinger方法插管、行选择性区域动脉并行灌注化疗。结果 所有病例病理检查均发现沿血管周围的癌细胞发生核固缩、碎裂,胞浆凝固、坏死、细胞间质水肿、纤维增生、炎细胞浸因和出现内膜增生、血管炎及血栓形成。结论订前选择性区域动脉灌注化疗要明显发迹结直肠癌患者的组织学形态,并使患者临床症状改善,对结直  相似文献   
29.
OBJECTIVE: To describe epidemiological features of HIV prevalence among female commercial sex workers (CSWs) in Cambodia, a cross-sectional study using a questionnaire study and serological tests was carried out from December 1997 to January 1998. We report the main results of the analyses of serological tests in this article. METHODS: Two hundred ninety six CSWs working in Sisophon and Poi Pet, located in northwest Cambodia, Bantey Mean Chey province, were recruited for interview based on a questionnaire on sexual behavior, and serological tests. The blood samples were examined for HIV antibody, Chlamydia trachomatis IgG antibody, TPHA, Hepatitis B surface antigen, and Hepatitis B surface antibody. The relationship between HIV and the other STD's was analyzed by using logistic regression analysis. RESULTS: The HIV seroprevalence rate was 43.9% (130 out of 296). The seropositive rate of Chlamydia trachomatis IgG antibody (C.T.-IgG-Ab) was 73.3% (217 out of 296). Logistic regression analysis showed a significant association between C.T.-IgG-Ab positive and HIV prevalence. (Odds Ratio: 5.33; 95% Confidence Interval, 2.82-10.07). CONCLUSIONS: This study suggests that the existence of Chlamydia trachomatis is closely related with HIV prevalence among CSWs in Cambodia. Other STDs may also increase susceptibility to male-to-female sexual transmission of HIV. This suggests that appropriate prevention against STDs will be needed for the control of HIV prevalence in Cambodia.  相似文献   
30.
According to our supposition that "humoral mechanism" plays an important role in the pathogenesis of portal hypertension due to cirrhosis, antagonists to some of humoral substances would lower the portal pressure in cirrhotic patients. Wedged hepatic venous pressure (WHVP) was used as an indicator for changes of portal pressure. Cimetidine was given intravenously to 8 cirrhotic patients, in whom an average lowering of 0.72 kPa (7.3 cm H2O) of WHVP was observed subsequently. This change was of clinical significance as compared with the previous results of splenorenal shunting operations.
  相似文献   
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