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BACKGROUND: The Internet has become a popular source of medical information for patients. Authors of health-related web pages are not required to adhere to any standard for medical content or accuracy. The goal of the present study was to assess the type, quality, and reliability of information about carpal tunnel syndrome that is available on the Internet. METHODS: The search phrase "carpal tunnel syndrome" was entered into five commonly used World Wide Web search engines. The search results then were given as an ordered list of universal resource locators, or web-site addresses. The top (first) fifty web sites from each of the five searches were combined to create a master roster of 250 web-site addresses. These web sites then were evaluated for authorship and content, and an informational value score ranging from 0 to 100 points was assigned to each. RESULTS: Thirty-three percent of the sites sold commercial products for the evaluation or treatment of carpal tunnel syndrome. An additional 30 percent were commercial web sites that did not sell products. Only 23 percent of the sites were authored by a physician or an academic organization. Fewer than half of the sites offered conventional information. Twenty-three percent of the sites offered unconventional or misleading information. The mean informational value of the web sites was 28.4 of a possible 100 points. CONCLUSIONS: The information about carpal tunnel syndrome on the Internet is of limited quality and poor informational value. The public and the medical communities need to be aware of these limitations so that the quality of medical information available on the World Wide Web can be improved.  相似文献   
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Insulin and glucose delivery (muscle perfusion) can modulate insulin-mediated glucose uptake. This study was undertaken to determine 1) to what extent insulin sensitivity modulates the effect of perfusion on glucose uptake and 2) whether this effect is achieved via capillary recruitment. We measured glucose disposal rates (GDRs) and leg muscle glucose uptake (LGU) in subjects exhibiting a wide range of insulin sensitivity, after 4 h of steady-state (SS) euglycemic hyperinsulinemia (>6,000 pmol/l) and subsequently after raising the rate of leg blood flow (LBF) 2-fold with a superimposed intrafemoral artery infusion of methacholine chloride (Mch), an endothelium-dependent vasodilator. LBF was determined by thermodilution: LGU = arteriovenous glucose difference (AVGdelta) x LBF. As a result of the 114+/-12% increase in LBF induced by Mch, the AVGdelta decreased 32+/-4%, and overall rates of LGU increased 40+/-5% (P < 0.05). We found a positive relationship between the Mch-modulated increase in LGU and insulin sensitivity (GDR) (r = 0.60, P < 0.02), suggesting that the most insulin-sensitive subjects had the greatest enhancement of LGU in response to augmentation of muscle perfusion. In separate groups of subjects, we also examined the relationship between muscle perfusion rate and glucose extraction (AVGdelta). Perfusion was either pharmacologically enhanced with Mch or reduced by intra-arterial infusion of the nitric oxide inhibitor N(G)-monomethyl-L-arginine during SS euglycemic hyperinsulinemia. Over the range of LBF, changes in AVGdelta were smaller than expected based on the noncapillary recruitment model of Renkin. Together, the data indicate that 1) muscle perfusion becomes more rate limiting to glucose uptake as insulin sensitivity increases and 2) insulin-mediated increments in muscle perfusion are accompanied by capillary recruitment. Thus, insulin-stimulated glucose uptake displays both permeability- and perfusion-limited glucose exchange properties.  相似文献   
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1. When care is taken to produce a peritonitis, which in itself is almost uniformly fatal, drainage of the thoracic duct in dogs has no favorable influence upon the course or result of the peritonitis. 2. Under the conditions of my experiments the thoracic duct did not serve in any important way as a drainage tract for bacterial contamination of the peritoneal cavity.  相似文献   
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This study compares different immunosuppressive regimens in the treatment of the lupus-like nephritis of NZB/W mice. Groups of 5-month-old female NZB/W mice were given azathioprine, cyclophosphamide and methylprednisolone in all one-, two- and three-drug regimens, each drug in the relatively low dose of 1.5 mg/kg/day. Treatment for 3 months with one or two drugs resulted in modest suppression of NZB/W disease. Mice receiving all three drugs had significantly less proteinuria, lower titers of anti-DNA antibody and less severe, histologically evident renal involvement than mice treated with one or two drugs. Survival at 1 year was 10% for untreated controls, 44% for one-drug-treated, 37% for two-drug-treated and 86% for the three-drug-treated mice. The survival for the three-drug regimen was significantly longer than any other group (P < 0.01). The three-drug regimen was synergistic, since mice treated with each drug at three times the dose had significantly more proteinuria after 3 months of treatment and lowered 1 year survival (33%). The beneficial effects of triple-drug therapy were attained without increased toxicity. This study represents the first controlled evaluation of single versus combination therapy in a model of autoimmune disease. Based on these results, a controlled evaluation of triple-drug therapy in human systemic lupus erythematosus appears warranted.  相似文献   
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Thirty-seven patients with criteria for systemic lupus erythematosus (SLE) and 18 normal controls were studied for their spontaneous background IgM antibody plaque-forming cell number to specific chemical haptens. Active SLE patients had significantly more plaque-forming cells in their peripheral blood to a total of five chemical determinants than did patients with inactive disease or controls. This increased number of plaque forming-cells correlated with depressed serum C3 levels by Spearman rank-order analysis. The finding of elevated numbers of spontaneous IgM plaque-forming cells to defined chemical haptens supports the concept that active SLE demonstrates a generalized increase in B-cell activity toward a variety of antigens.  相似文献   
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