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401.
OBJECTIVE: To compare two modem mesh-based "tension free" hernioplasties, laparoscopic repair and mesh plug technique. DESIGN: Prospective, non-randomised study. SETTING: Two major medical centres, Greece. SUBJECTS: 471 patients with 543 inguinal hernias. INTERVENTION: Patients entering the study were treated in two major medical centres either by laparoscopic repair under general anaesthesia (n = 237) in hospital A, or by insertion of a mesh plug under monitored local, epidural, or spinal anaesthesia (n = 234) in hospital B. Patients with known bilateral inguinal hernias, femoral hernias, and those with both inguinal hernias and cholelithiasis were encouraged to undergo laparoscopic repair. MAIN OUTCOME MEASURES: Operative time, hospital mortality, morbidity and length of stay, costs, time to return to work, and recurrence rate. RESULTS: The median operative time for laparoscopic repair was significantly longer (57 compared with 33 minutes, p < 0.001). Laparoscopic repair was more costly (1,200 US dollars compared with 500), and technically more demanding than insertion of a mesh plug. The median postoperative hospital stay, consumption of narcotic analgesics, and return to full work and heavy activities were similar in the two groups, whereas light activities were started earlier after plug repair [5.4 (2.4) compared with 3.4 (1.5) hours, p < 0.0001]. There were 6 recurrences in the laparoscopic group and 1 in the plug group. CONCLUSIONS: Mesh plug insertion is faster, cheaper, technically easier, does not require general anaesthesia, and is suitable to be done by surgeons as part of their general practice without special instruments and by junior surgeons. Plug repair resulted in fewer short or long term complications and reduced the recurrence rate.  相似文献   
402.
1 对象和方法1.1 对象  1986 - 0 6 /1998- 12共行胃镜检查 2 40 0 0人次 ,发现 型早期胃癌本组 11(男 9,女 2 )例 ,年龄 40~ 71(平均5 2 .3)岁 ,上胀隐痛 6例 ,腹胀 3例 ,纳差 ,乏力 2例 ,伴黑便 2例 .1.2 方法 按常规进行胃镜检查 .手术前于外院及本院共行胃镜检查 19次 ,除 1次因故未取活检外 ,其余 18次均于疑诊部位取活检 2~ 10块 ,11例中有 6例系 1次确诊 ,3例经 2次胃镜检查及活检确诊 ,1例经 3次胃镜检查及活检确诊 ,1例 b型早期胃癌共经 4次胃镜检查 ,3次活检方得以确诊 .2 结果 胃窦部 5例 ,胃角 2例 ,胃体小弯 3例 ,…  相似文献   
403.
The hippocampus and frontal lobes both contribute to episodic memory performance. In the present study, the authors evaluated the relative contributions of hippocampus, frontal lobes, anterior temporal cortex, and posterior cortex to memory performance in neurodegenerative patients and normal older controls. Subjects (n=42) were studied with structural MRI and a memory paradigm that measured delayed recall, semantic clustering during recall, recognition discriminability, and recognition response bias. Data were analyzed with multiple regression. Consistent with the authors' hypotheses, hippocampal volumes were the best predictor of delayed recall and recognition discriminability, whereas frontal volumes were the best predictor of semantic clustering and response bias. Smaller frontal volumes were associated with less semantic clustering during recall and a more liberal response bias. Results indicate that hippocampal and frontal contributions to episodic memory can be dissociated, with the hippocampus more important for memory accuracy, and frontal structures more important for strategic processing and decision making.  相似文献   
404.
BACKGROUND & AIMS: Helicobacter pylori uniquely colonizes the human stomach and produces gastric mucosal inflammation. High-output nitric oxide production by inducible nitric oxide synthase (iNOS) is associated with immune activation and tissue injury. Because mononuclear cells comprise a major part of the cellular inflammatory response to H. pylori infection, the ability of H. pylori to induce iNOS in macrophages was assessed. METHODS: H. pylori preparations were added to RAW 264.7 murine macrophages, and iNOS expression was assessed by Northern blot analysis, enzyme activity assay, and NO2- release. RESULTS: Both whole H. pylori and French press lysates induced concentration-dependent NO2- production, with peak levels 20-fold above control. These findings were paralleled by marked increases in iNOS messenger RNA and enzyme activity levels. iNOS expression was synergistically increased with interferon gamma, indicating that the H. pylori effect can be amplified by other macrophage-activating factors. Studies of lipopolysaccharide (LPS) content and polymyxin B inhibition of LPS suggested that the H. pylori effect was attributable to both LPS- dependent and -independent mechanisms. CONCLUSIONS: iNOS expression in macrophages is activated by highly stable H. pylori products and may play an important role in the pathogenesis of H. pylori-associated gastric mucosal disease. (Gastroenterology 1996 Dec;111(6):1524-33)  相似文献   
405.
Butyrate analogues have been shown to increase fetal hemoglobin (HbF) production in vitro and in vivo. Sodium phenylbutyrate (SPB), an oral agent used to treat individuals with urea-cycle disorders, has been shown to increase HbF in nonanemic individuals and in individuals with sickle cell disease. We have treated eleven patients with homozygous beta thalassemia (three transfusion dependent) and one sickle-beta- thalassemia patient with 20 g/d (forty 500-mg tablets) of SPB for 41 to 460 days. All patients showed an increase in the percent of F reticulocytes associated with treatment, but only four patients responded by increasing their Hb levels by greater than 1 g/dL (mean increase, 2.1 g/dL; range, 1.2 to 2.8 g/dL). None of the transfusion- dependent thalassemia subjects responded. Increase in Hb was associated with an increase in red blood cell number (mean increase, 0.62 x 10(12)/L), and mean corpuscular volume (mean increase, 6 fL). Changes in percent HbF, absolute HbF levels, or alpha- to non-alpha-globin ratios as measured by levels of mRNA and globin protein in peripheral blood did not correlate with response to treatment. Response to treatment was not associated with the type of beta-globin mutation, but baseline erythropoietin levels of greater than 120 mU/mL was seen in all responders and only two of eight nonresponders to SPB. Compliance with treatment was greater than 90% as measured by pill counts. Side effects of the drug included weight gain and/or edema caused by increase salt load in 2/12, transient epigastric discomfort in 7/12, and abnormal body odor in 3/12 subjects. Two splenectomized patients who were not on prophylactic antibiotics developed sepsis while on treatment. We conclude that SPB increases Hb in some patients with thalassemia, but the precise mechanism of action is unknown.  相似文献   
406.
ObjectiveTo assess changes in the quality of primary care in two megacities following the introduction of health system reforms in China.MethodsWe conducted multistage stratified random face-to-face surveys of patients visiting community health centres in Shanghai in 2011 and 2013, and Shenzhen in 2012 and 2013. Quality of primary care was measured using an assessment tool. Difference-in-difference analyses based on multiple linear regressions were used to compare the changes over time, after controlling for potential confounders.FindingsMost (2721) of the 3214 participants used a community health centre as their regular source of care and were included in our analyses. The mean total scores for quality of primary care were similar for Shanghai and Shenzhen at baseline. In Shenzhen, the mean total scores for all participants and those on low incomes had worsened by 0.922 (95% CI: 0.629 to 1.215) and 1.203 (95% CI: 0.397 to 2.009), respectively. In Shanghai, however, there were improvements in the mean total scores which included increases in the scores for first-contact utilization, continuity, coordination of information and comprehensiveness.ConclusionThe quality of primary care improved in Shanghai but not in Shenzhen. This may be because, in Shanghai, beneficial long-term relationships between patients and general practitioners were supported by capitation payments and the provision of services tailored to the local health priorities.  相似文献   
407.
408.
The inhibition mechanism of a polysaccharide anticoagulant, depolymerized holothurian glycosaminoglycan (DHG), was examined by analyzing its effects on the clotting time of human plasma depleted of antithrombin III (ATIII), of heparin cofactor II (HCII), or of both heparin cofactors. The effect exerted by this agent on the activation of prothrombin and factor X in purified human components were also examined and all effects were compared with those of other glycosaminoglycans (GAGs). The capacity of DHG to prolong activated partial thromboplastin time was not reduced in ATIII-depleted, HCII- depleted, HCII-depleted, or ATIII- and HCII-depleted plasma, whereas its capacity to prolong prothrombin time and thrombin clotting time was reduced in HCII-depleted plasma. DHG inhibited the amidolytic activity of thrombin in the presence of HCII with a second order rate constant of 1.2 x 10(8) (mol/L)-1 min-1. These results indicated that DHG has two different inhibitory activities, one being an HCII-dependent thrombin inhibition and the other an ATIII- and HCII-independent inhibition of the coagulation cascade. The heparin cofactors- independent inhibitory activity of DHG was investigated in the activation of prothrombin by factor Xa and in the activation of factor X by tissue factor-factor VIIa complex or by factor IXa. DHG significantly inhibited the activation of factor X by factor IXa in the presence of factor VIIIa, but not in the absence of factor VIIIa. The interaction between DHG and factors IXa, VIIIa, and X was investigated with a DHG-cellulofine column, on which DHG had strong affinity for factors IXa and VIIIa. These findings show that the heparin cofactors- independent inhibition exhibited by DHG was caused by inhibition of the interaction of factor X with the intrinsic factor Xase complex, probably by binding to the factor IXa-factor VIIIa complex.  相似文献   
409.
Binding of urokinase-type plasminogen activator (uPA) to its glycosylphosphatidylinositol-anchored receptor (uPAR) initiates signal transduction, adhesion, and migration in certain cell types. To determine whether some of these activities may be mediated by associations between the uPA/uPAR complex and other cell surface proteins, we studied the binding of complexes composed of recombinant, soluble uPA receptor (suPAR) and single chain uPA (scuPA) to a cell line (LM-TK- fibroblasts) that does not express glycosylphosphatidylinositol (GPI)-anchored proteins to eliminate potential competition by endogenous uPA receptors. scuPA induced the binding of suPAR to LM-TK- cells. Binding of labeled suPAR/scuPA was inhibited by unlabeled complex, but not by scuPA or suPAR added separately, indicating cellular binding sites had been formed that are not present in either component. Binding of the complex was inhibited by low molecular weight uPA (LMW-uPA) indicating exposure of an epitope found normally in the isolated B chain of two chain uPA (tcuPA), but hidden in soluble scuPA. Binding of LMW-uPA was independent of its catalytic site and was associated with retention of its enzymatic activity. Additional cell binding epitopes were generated within suPAR itself by the aminoterminal fragment of scuPA, which itself does not bind to LM-TK- cells. When scuPA bound to suPAR, a binding site for alpha 2-macroglobulin receptor/LDL receptor-related protein (alpha 2 MR/LRP) was lost, while binding sites for cell-associated vitronectin and thrombospondin were induced. In accord with this, the internalization and degradation of cell-associated tcuPA and tcuPA-PAI- 1 complexes proceeded less efficiently in the presence of suPAR. Further, little degradation of suPAR was detected, suggesting that cell- bound complex dissociated during the initial stages of endocytosis. Thus, the interaction of scuPA with its receptor causes multiple functional changes within the complex including the dis-appearance of an epitope in scuPA involved in its clearance from the cell surface and the generation of novel epitopes that promote its binding to proteins involved in cell adhesion and signal transduction.  相似文献   
410.
Basilar artery fenestration aneurysms are very rare and endovascular management of large and complex aneurysms is extremely challenging. Most of these type of cases are managed with stent assisted coiling, dual flow diverters (FD) and single FD with additional coiling of aneurysm and occlusion of one of the vertebral artery. Here, we report a case of large complex basilar artery fenestration aneurysm successfully treated with single FD using novel technique called “crossing flow diverter technique” without any additional coiling of aneurysm or occlusion of vertebral artery. Using this technique cost of procedure and procedural complexity inherent with other above mentioned techniques can be significantly reduced.  相似文献   
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