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71.
失眠的评价     
失眠的定义失眠分为急性和慢性失眠.急性失眠通常持续时间不超过2 w,与应激状态有关,例如上班、搬家、婚姻或亲人朋友的去世等.而慢性失眠则是失眠持续超过3 w以上,或者不充足睡眠伴随着日间睡意和抑郁,且持续时间不少于1个月.  相似文献   
72.
对QT离散度实质的探讨   总被引:2,自引:0,他引:2  
为探讨QT离散度(QTd)的真实意义,观察139例急性心肌梗死(AMI,AMI组)及109例正常人(对照组)的最长QT间期(QTmax)、校正QTmax(QTcmax)及QTd的变化。结果:①AMI组的QTmax、QTcmax和QTd均显著高于对照组(分别为422.60±30.51msvs382.46±23.40ms、460.21±28.96msvs388.51±20.15ms、59.80±28.40msvs39.43±12.21ms,P均<0.001)。②AMI组中发生严重室性心律失常(VA)患者(114例)的QTmax、QTcmax、QTd与无VA的患者(25例)相比,均有显著差异(分别为448.58±33.40msvs416.10±35.30ms、481.43±35.17msvs439.60±27.10ms、66.90±20.72msvs48.32±23.61ms,P均<0.001)。认为AMI时QTd系T向量环在不同导联上的“投影”差异所引起的,其异常的本质是QT间期延长  相似文献   
73.
Transfusion practice in central Virginia   总被引:4,自引:0,他引:4  
SS Cook  ; J Epps 《Transfusion》1991,31(4):355-360
  相似文献   
74.
BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH), caused by somatic mutation of hematopoietic cells, is associated with complement-mediated hemolysis and a hypercoagulable state. Thrombotic complications in this disease are associated with reduced survival. We report a patient with PNH complicated by intracranial venous thrombosis and Budd-Chiari syndrome, who was managed with transjugular intrahepatic portosystemic shunt. CASE PRESENTATION: A 26-year-old man presented with thrombosis of the superior sagittal and right sigmoid sinuses. Initial investigations did not reveal any underlying cause. Nine months later, he developed hepatic venous thrombosis. At this time, Ham test was positive. Flow cytometry confirmed the diagnosis of PNH. The patient was treated with transjugular intrahepatic portosystemic shunt; one episode of stent blockage one month later was managed successfully with balloon dilatation and restenting. CONCLUSION: PNH should be considered in patients with unexplained venous thrombosis. Thrombosis in these patients needs to be managed with prolonged anticoagulation. For Budd-Chiari syndrome in patients with underlying PNH, transjugular intrahepatic portosystemic shunt may be a good option but caution is needed to prevent stent occlusion.  相似文献   
75.

Objectives

The aim of this study was to evaluate the HIV‐1 RNA pooled nucleic acid amplification testing (NAAT) strategy to screen pregnant women in the ‘window period’ of acute HIV infection (AHI) in rural South Africa.

Methods

In 2007 and 2008, 750 consecutive pregnant women on their first antenatal care visit to a primary health care clinic were tested anonymously for HIV infection. HIV‐1 RNA pooled NAAT was performed on HIV antibody‐negative samples. All positive pools were tested individually and positive samples were classified as incident cases to calculate HIV incidence.

Results

The overall HIV prevalence was 37.3% [95% confidence interval (CI) 34.3–41.3]. Of the 467 HIV antibody‐negative samples, four (0.9%) were HIV‐1 RNA‐positive. The mean viral load in the four samples was 386 260 HIV‐1 RNA copies/mL (range 64 200–1 228 130). The HIV incidence was 11.2% per year (95% CI 0.3–22.1) and all women with AHI were ≤21 years of age.

Conclusions

Identifying AHI in pregnancy is important for health interventions to reduce perinatal and heterosexual transmission of HIV, and to estimate HIV incidence for epidemiological surveillance.  相似文献   
76.
77.
78.
促红细胞生成素对实验性肾性贫血的作用   总被引:1,自引:0,他引:1  
促红细胞生成素(erythropoietin,EPO)是由肾细胞分泌的一种糖蛋白激素。从人胚肾细胞中诱导,经生物化学方法分离、提纯得到此品。本试验用5/6肾切除的方法造成大鼠慢性肾衰性(CRF)贫血,研究不同剂量EPO对CRF贫血的作用。结果表明EPO有显著的促进红细胞生成,改善CRF贫血状态,使其接近或达到正常水平,最佳剂量为1000 U/kg,并可预防实验性贫血,对正常鼠未见明显作用。  相似文献   
79.
BACKGROUND & AIMS: After partial hepatectomy, liver regeneration occurs with the return of hepatocyte mass to normal, Limited data exist regarding the renewal of the biliary tree after partial hepatectomy. This study tested the hypothesis that, after partial hepatectomy, the biliary tree regenerates by proliferation of the remaining cholangiocytes, leading to an increase in secretin-induced ductal bile secretion. METHODS: After 70% partial hepatectomy, cholangiocyte proliferation was assessed in situ by morphometric analysis and In vitro by measurement of 3H-thymidine incorporation. Ductal secretion was estimated by measurement of secretin receptor gene expression and adenosine 3',5'-cyclic monophosphate (cAMP) levels in vitro and by the effect of secretin on ductal bile secretion in vivo. RESULTS: DNA synthesis was undetectable in control cholangiocytes, increased and peaked at day 3 after partial hepatectomy, and returned to normal by day 28. Morphometric analysis showed regrowth of the biliary tree beginning at day 1 with restoration by day 10. The expression of secretin receptor gene and secretin-induced cAMP levels and secretin- induced bicarbonate-rich choleresis increased during the period of bile duct renewal. CONCLUSIONS: After partial hepatectomy, the increase in secretin-induced ductal bile secretion observed during bile duct renewal results from proliferation of remaining cholangiocytes. (Gastroenterology 1996 Dec;111(6):1633-44)  相似文献   
80.
Laparoscopic cholecystectomy is the gold standard for gallbladder removal and the most common laparoscopic procedure worldwide. With the advent of laparoscopic surgery and its continuous development, the focus has shifted to ‘scarless’ surgery. In recent times, the innovative technique of single-incision laparoscopic surgery (SILS) has been applied in gallbladder removal and even more complex biliopancreatic procedures to further minimize the invasiveness of the surgery. Newer developments in laparoscopic equipments and instrumentation have helped to further evolve this field of minimally invasive surgery. Literature search was performed using the following online search engines: Google, Medline, PubMed, Cochrane, and the online Springer link library. The terms used for the search were as follows: SILS, LESS, single-incision laparoscopic surgery, single-port laparoscopic surgery, SILS cholecystectomy, and SILS pancreatic surgery. Articles that matched the search criteria were selected and extensively reviewed. Moreover, pertinent information on instrumentation and technology for SILS and LESS was obtained by accessing websites of manufacturers. Although SILS represents the search for an essentially scarless surgery, there is still not a widespread use and uniformity of this procedure. SILS is performed either by single- or multiple-port technique. In the present article, we present a review of the potential benefits, limitations, and risks of SILS in biliary and pancreatic diseases. There are many studies showing benefits in cholecystectomy. A few case reports have also emerged about its feasibility in procedures such as cystogastrostomy and limited pancreatic resection. Further research and development of this technique is needed to arrive at a tangible conclusion about the perceived benefits of SILS. Randomized studies to compare SILS with traditional laparoscopy are essential.  相似文献   
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