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BACKGROUND: Normal endothelial function depends on nitric oxide (NO) release by endothelial cells. Asymmetric dimethylarginine (ADMA), by competing with L-arginine, inhibits NO production and may lead to endothelial dysfunction and atherosclerotic development. Our aim was to ascertain the association between ADMA and coronary artery calcification (CAC), a marker of atherosclerotic coronary disease burden. DESIGN: A nested case-control study within the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, an observational study among young adults residing in four US cities. METHODS: Participants were 263 white and black male and female cases with the presence of CAC and 263 sex and race-matched controls without evidence of CAC by computed tomography, 33-47 years old in 2000-2001. RESULTS: The median level (range) of ADMA was significantly higher in cases (0.55; 0.20-2.22 micromol/l) than in controls (0.53; 0.32-1.30 micromol/l; P=0.03). In conditional logistic regression adjusting for age, field center, educational attainment, smoking status, alcohol consumption, body mass index, waist circumference, hypertension, diabetes, low-density lipoprotein and high-density lipoprotein-cholesterol, triglycerides, renal function and C-reactive protein, the highest tertile of ADMA, compared with the lowest tertile, was associated with 1.80 (95% confidence interval 1.03-3.15) increased odds of the presence of any CAC. By linear regression, a significant independent relationship was also found between ADMA and the degree of CAC. CONCLUSION: These results support a role for ADMA as a biochemical marker of CAC.  相似文献   
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The aim of this work was to evaluate NMR cerebellar abnormalities in children with severe acute ataxia. Among 8 consecutively observed children, NMR performed in 6 during the acute phase was pathological in 4, demonstrating hyperintense signal in the T2-weighed sequences of dentate nuclei (2 cases, associated in 1 with hyperintense signal in the medium cerebellar peduncle) or of the cerebellar cortex associated with cerebellar swelling (2 cases). NMR performed in 7 cases after at least 1 month of evolution showed cerebellar atrophy in 4 cases. After 1 to 6 years of clinical follow-up, 4/8 children had clinical sequellae, including 3 of the 4 children with initially abnormal NMR. Conversely, the 2 patients with initially normal NMR had a good clinical recovery. NMR during the acute phase gives informations on prognosis in patients with severe acute ataxia.  相似文献   
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Monoclonal antibodies against the alkaline phosphatase of Pseudomonas aeruginosa were produced from spleen cells of BALB/c mice primed with purified alkaline phosphatase of P. aeruginosa ATCC 10145 and SP20/Ag-14 myeloma cells. The eight stable clones established produced antibodies that reacted by enzyme-linked immunosorbent and indirect immunofluorescence assays with all bacterial strains of P. aeruginosa, including the 17 serotypes and two nontypable strains. Three of the clones cross-reacted only with some Pseudomonas species of the rRNA homology group I defined by N. J. Palleroni (in N. R. Krieg and J. G. Holt, ed., Bergey's Manual of Systematic Bacteriology, 8th ed., p. 140-218, 1984). The other clones also interacted with other species, including Pseudomonas acidovorans and Xanthomonas maltophilia. Because other species of the genera Aeromonas and Acinetobacter and species of the family Enterobacteriaceae were not detected by these monoclonal antibodies, the antibodies could be used as reagents for routine detection of P. aeruginosa in clinical specimens. Interactions of the antibodies with other Pseudomonas species such as P. fluorescens and P. stutzeri are not important, since these species are susceptible to the same antipseudomonal agents.  相似文献   
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Direct-acting antiviral (DAA) therapy has transformed the management of human immunodeficiency virus (HIV) and hepatitis C (HCV) coinfected patients with advanced liver disease. STOP-Coinfection was a multicenter prospective and retrospective, open-label study using sofosbuvir-based DAA therapy to treat HIV/HCV-coinfected participants pre– or post–liver transplant (LT). Sixty-eight participants with end-stage liver disease (Child-Turcotte-Pugh score ≥7 and Model for End-Stage Liver Disease score 6–29) were enrolled, 26 had hepatocellular carcinoma. Forty-two participants were treated pre–LT and 26 post–LT. All participants completed therapy without need for dose reduction or transfusion; eight required two or more courses of therapy. Ninety-three percent achieved a sustained virologic response and DAA therapy was well tolerated. Despite HCV cure, 12 end-stage liver disease participants required subsequent LT, 7 for decompensated liver disease. Thirteen participants died, 10 with decompensated liver disease pre–LT and three post–LT. Overall, transplant free survival was 42.8% at 4 years and post–LT survival was 87.9% at 5 years. We conclude that sofosbuvir-based DAA therapy is safe and highly effective in HCV-HIV patients with decompensated liver disease and post–LT, with post–LT survival rates comparable to other indications. This removes one of the last barriers to liver transplantation in this challenging cohort of recipients.  相似文献   
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A case-control study design was used to examine whether habitual physical activity prior to the final menstrual period (FMP) was associated with reduced risk of vasomotor and other symptoms during the perimenopausal period. Both cases and controls were identified through a screening interview with randomly selected women members, ages 48-52, of a large health maintenance organization. Cases (n = 82) were defined as women 3-12 months past their FMP who reported regularly having hot flashes or night sweats at least once a day or night during the 3 months following their FMP. Controls (n = 89) were of the same biologic age with respect to the FMP but reported vasomotor symptoms less than once a week during the reference time period. Neither cases nor controls had a history of hormone replacement therapy (HRT), hysterectomy, or bilateral oophorectomy. Case-control status, habitual physical activity (including recreational, housework, child care, and occupational activity), and psychological and somatic symptoms were assessed by self-report. Participation in vigorous recreational activity during the year prior to the FMP was not associated with reduced risk of frequent vasomotor symptoms after the FMP (odds ratio [OR] = 1.03 for a 50-unit increase in activity score, 95% confidence interval [CI] = 0.97-1.1). This lack of relationship was observed in all domains of activity. Factors that were associated with decreased risk included higher body mass index (BMI) (weight in kg/(height in meters)2) (OR = 0.95 per 1 unit increase in BMI, 95% CI = 0.90-1.00) and higher education (having a college degree relative to less education) (OR = 0.56, 95% CI = 0.40-0.80). Physical activity was also unassociated with reduced risk of psychologic distress, depressive feelings, or somatic symptoms, but, relative to controls, having vasomotor symptoms (being a case) was strongly associated with increased risk of experiencing those symptoms (OR ranging from 1.83 for psychologic distress to 2.84 for depressive feelings). These findings suggest that regular physical activity before the FMP may not reduce the likelihood of experiencing symptoms during the perimenopause, although the small sample size may limit the inferences that can be drawn.  相似文献   
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We have previously reported an overexpression of Smad1 in follicular lymphoma (FL) cells, which are characterized by the t(14;18) bcl2/IgH translocation. Smad1 is commonly involved in bone morphogenetic protein but not in tumor-transforming growth factor beta (TGFbeta) signaling pathways. This study focuses on Smad1 signaling pathway in non-Hodgkin lymphoma cells including follicular or large-cell lymphoma cells. Our results support the notion that phosphorylation of Smad1 is mediated by TGFbeta present in the microenvironment and occurs in FL in vivo. Using an in vitro coculture system mimicking interactions between stroma cells and FL cells, we found that both the cell partners release TGFbeta at a sufficient concentration to activate Smad pathways in the malignant cells. This Smad1 activation involves TGFbetaRII but not ALK-1 receptors, and does not compete with the Smad2 pathway. Moreover, proliferation assays performed on lymphoma cells expressing wild-type or mutated Smad1, or in which endogenous Smad1 level was decreased by gene silencing, strongly supported that overexpression and activation of Smad1 modifies the biological response of lymphoma B cells to TGFbeta family members. This work opens new insights into aberrant Smad pathways and their pathophysiological role in FL and in other non-Hodgkin lymphomas.  相似文献   
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Laparoscopic liver resections: a feasibility study in 30 patients   总被引:76,自引:0,他引:76       下载免费PDF全文
OBJECTIVE: To assess the feasibility and safety of laparoscopic liver resections. SUMMARY BACKGROUND DATA: The use of the laparoscopic approach for liver resections has remained limited for technical reasons. Progress in laparoscopic procedures and the development of dedicated technology have made it possible to consider laparoscopic resection in selected patients. METHODS: A prospective study of laparoscopic liver resections was undertaken in patients with preoperative diagnoses including benign lesion, hepatocellular carcinoma with compensated cirrhosis, and metastasis of noncolorectal origin. Hepatic involvement had to be limited and located in the left or peripheral right segments (segments 2-6), and the tumor had to be 5 cm or smaller. Surgical technique included CO2 pneumoperitoneum and liver transection with a harmonic scalpel, with or without portal triad clamping or hepatic vein control. Portal pedicles and large hepatic veins were stapled. Resected specimens were placed in a bag and removed through a separate incision, without fragmentation. RESULTS: From May 1996 to December 1999, 30 of 159 (19%) liver resections were included. There were 18 benign lesions and 12 malignant tumors, including 8 hepatocellular carcinomas in cirrhotic patients. Mean tumor size was 4.25 cm. There were two conversions to laparotomy (6.6%). The resections included 1 left hepatectomy, 8 bisegmentectomies (2 and 3), 9 segmentectomies, and 11 atypical resections. Mean blood loss was 300 mL. Mean surgical time was 214 minutes. There were no deaths. Complications occurred in six patients (20%). Only one cirrhotic patient developed postoperative ascites. No port-site metastases were observed in patients with malignant disease. CONCLUSION: Laparoscopic resections are feasible and safe in selected patients with left-sided and right-peripheral lesions requiring limited resection. Young patients with benign disease clearly benefit from avoiding a major abdominal incision, and cirrhotic patients may have a reduced complication rate.  相似文献   
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