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41.
Children who work in agriculture suffer more than 23,000 injuries and 300 fatalities on American farms every year. Using survey data collected from a random sample of working teens (ages 14 to 17) in North Carolina, the authors analyze the farm-based hazard exposure and injury experiences of teens who work on farms. The group of farmworking teens (N = 141) is 72 percent male, has a mean age of 16.6 years, and is, on average, in the 10th grade. The data show that teens working on farms in North Carolina are exposed to significant safety hazards throughout their farmworking careers. A majority of the respondents in this group of farmworkers reported exposure to tractors, large animals, all-terrain vehicles, farm trucks, and rotary mowers, and more than one-third reported exposure to pesticides and tobacco harvesters. Common reported injuries include insect stings, cuts, burns, and falls. The researchers find that gender, age, and farmwork experiences are related to variations in types of hazards to which teens are exposed and in the types of injuries they suffer. These variables also are related to the overall complexity of the teens' farmwork experiences and the burden of injury endured by teens.  相似文献   
42.
A community hospital experience of 238 instances of carcinoma of the pancreas during a 23 year period has been reviewed to see if there has been any change in survival, hospital stay, morbidity and operative strategy during the two decades included in this study as a result of improved diagnostic modalities and perioperative management. The results of this review indicate an increasing incidence of carcinoma of the pancreas in the second half of the study but also document a large number of patients whose diagnosis has been unsuspected until autopsy. The mortality for palliative bypass procedures dropped significantly in the second half of the study and provided a mean survival time of 7.6 months for this group of patients, approximately twice that of patients explored without palliation. Resectional procedures showed a very significant drop in mortality rate in the second half of the study and were used more extensively. Mean survival time of patients undergoing resectional procedures was 18.3 months with two prolonged survivors out of 22 patients. Significant operative morbidity remains a major problem and the chief cause of protracted postoperative stay and did not diminish in the second half of this study. Complications were primarily technical in nature. With this in mind, consideration should be given to concentrating the experience in pancreatic resectional operations in the hands of a limited number of surgeons within any given community.  相似文献   
43.
Obstruction of a Bjork-Shiley mitral valve prosthesis occurred in a 41 year old woman due to pannus tissue growing over the valve and impairing disc opening. The unusual intermittent nature of the obstruction was clearly demonstrated by Doppler ultrasound. The pannus was excised and the valve prosthesis replaced successfully with a Carpentier-Edwards xenograft.  相似文献   
44.
In 82 patients who underwent gastroduodenoscopy, acute and chronic gastric mucosal inflammation was scored for severity, and systemic humoral immune responses to Helicobacter pylori antigens were assessed by enzyme-linked immunosorbent assays. On the basis of culture, gastric histology, and serologic evaluation, 33 patients were classified as H. pylori infected and 36 were classified as uninfected. Thirteen patients had negative cultures and stains but were seropositive and were analyzed separately from the other two groups. Specific serum immunoglobulin G (IgG) subclass responses to H. pylori whole-cell antigens and specific IgG responses to the 54-kDa heat shock protein homolog (Hp54K) and vacuolating cytotoxin were significantly greater in infected than in uninfected patients as were specific IgA responses to whole-cell antigens and cytotoxin (P < 0.001). Among the H. pylori-infected persons, serum IgG responses to Hp54K and to the vacuolating cytotoxin were correlated with acute mucosal inflammatory scores. In contrast, serum IgA responses to whole-cell sonicate and to vacuolating cytotoxin were inversely related to chronic inflammatory scores. By multivariant regression analysis, only specific serum IgG responses to Hp54K correlated with severity of inflammation (both acute and chronic; P < 0.001); these responses may be markers of inflammation or these antibodies could play a direct role in the pathogenesis of H. pylori-induced inflammation.  相似文献   
45.
Recent advances have been made in the treatment of pancreas cancer. Specialized pancreas centres have reported an increasing rate of resections with reduced postoperative mortality. On account of the highly aggressive nature of pancreas cancer, there is a great challenge in identifying effective therapy concepts for advanced stages of the cancer as well as for the development of resection-associated measures. As large-scale, randomised, controlled studies are lacking, the additive therapy concepts after resection do not have a sufficiently scientific basis. The ESPAC-1 study, which included 600 patients, surpassed all previous studies on adjuvant therapy for pancreas cancer. This study has shown,for example, that the most promising adjuvant chemotherapy with 5-fluorouracil and folic acid leads to an equal if not better result than the multimodal regimen. This regimen can be superseded with the use of Gemcitabine, which will be evaluated in the ESPAC-3 study that includes 990 patients from various European countries including Germany, as well as from Canada and Australia. Participation in the large, phase-3 study therefore plays a key role in the continued development of the management of pancreas cancer.  相似文献   
46.
The impact of multiple donor and recipient variables on functional survival of 307 cadaveric pancreas allografts transplanted in 253 recipients at the authors' institution between July 25, 1978 and September 4, 1990 was determined using the Cox proportional hazards regression model. Relative risk of graft loss was calculated for all cases as well as for technically successful (TS) ones. Factors with an impact in descending order of significance for TS cases were immunosuppression (RR = 3.9 for double-drug versus triple-drug maintenance, p less than 0.0001); recipient category (RR = 2.4 for pancreas alone versus simultaneous pancreas/kidney, p = 0.009); retransplantation (RR = 1.8 for retransplants versus primary grafts, p = 0.007); donor hyperglycemia (RR = 1.7 for blood glucose greater than or equal to 200 versus less than 200 mg/dL, p = 0.02); human leukocyte antigen (HLA) matching (RR = 2.1 for poor versus a good match, p = 0.04). A logistic regression analysis also was performed to determine which factors predisposed to technical failure; none were identified. To make the model as relevant as possible to their current program, the authors analyzed only the bladder-drained cases (n = 221; 1984 to 1990). All patients received triple therapy. Recipient category, retransplantation, donor hyperglycemia, and degree of HLA matching remained as significant risk factors. Construction of estimated survival curves showed that the results of retransplantation were significantly improved, and the penalty incurred by using hyperglycemic donors was partially ameliorated by using well-matched donors. Because preservation times up to 30 hours did not exert an adverse effect on outcome, an argument is made to share pancreata between centers to achieve good matches.  相似文献   
47.
Kupffer cells are exposed directly to a number of factors in the portal circulation that can modify or regulate their responses to septic stimuli. The gut represents a potential source of a number of these factors including endotoxin, lymphokines, and prostaglandins. We examined Kupffer cells from germfree rats and germfree rats exposed to endotoxin or bacteria via their GI tracts to determine the importance of the intestinal flora in maintaining or modulating Kupffer cell responses. Kupffer cells from germfree animals were reduced in numbers and failed to respond to LPS in Kupffer cell: hepatocyte coculture. When germfree rats were exposed to bacterial endotoxin or bacteria via the gastrointestinal tract their Kupffer cells increased in numbers to normal and the cells responded to LPS in culture. Intestinal overgrowth with Escherichia coli for 2 days activated the Kupffer cells and significantly increased Kupffer cell sensitivity to LPS. These data suggest that the environment of the gastrointestinal tract is important for normal Kupffer cell responses and that intestinal bacterial overgrowth can modify Kupffer cell responses to septic stimuli.  相似文献   
48.
49.
Helicobacter pylori is a spiral, gram-negative bacterium which causes chronic gastritis and plays a critical role in peptic ulcer disease, gastric carcinoma, and gastric lymphoma. H. pylori expresses significant urease activity which is an essential virulence factor. Since a significant fraction of urease activity is located on the surface of the bacterium, the urease molecule is a logical choice as an antigen for a vaccine; currently recombinant urease apoenzyme is being tested as a vaccine in phase II clinical trials. We have recently demonstrated that urease and HspB (a homolog of the GroEL heat shock protein) become associated with the surface of H. pylori in vitro in a novel manner: these cytoplasmic proteins are released by bacterial autolysis and become adsorbed to the surface of intact bacteria, reflecting the unique characteristics of the outer membrane. To determine if similar mechanisms are operative in vivo, we determined the ultrastructural locations of urease and HspB within bacteria present in human gastric biopsies. Our results demonstrate that both urease and HspB are located within the cytoplasm of all bacteria examined in human gastric biopsies. Interestingly, a significant proportion of the bacteria examined also possessed variable amounts of surface-associated urease and HspB antigen (from 5 to 50% of the total antigenic material), indicating that in vivo, H. pylori has surface characteristics which enable it to adsorb cytoplasmic proteins. This is consistent with our altruistic autolysis model in which H. pylori uses genetically programmed bacterial autolysis to release urease and other cytoplasmic proteins which are subsequently adsorbed onto the surface of neighboring viable bacteria. These observations have important implications regarding pathogenesis and development of vaccines for H. pylori.  相似文献   
50.
A number of 7-benzoylbenzofuran-5-ylacetic acids and 7-benzoylbenzothiophene-5-ylacetic acids were synthesized. The compounds were generally only 1/2 to 3 times as potent as phenylbutazone in the rat paw edema antiinflammatory assay. However, they show greater activity as analgetic agents. The most active compound is 7-[4-(methylthio)-benzoyl]benzofuran-5-ylacetic acid (5g) having 57 times the potency of aspirin in the mouse writhing analgetic assay. This compound caused virtually no gastric ulceration in rats at doses of up to 90 mg/kg.  相似文献   
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