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The present study was conducted to elucidate the effects of tirilazad mesylate (U-74006F), a potent inhibitor of lipid peroxidation, on vessel diameter, capillary perfusion, and contractile function of rat cremaster muscle during a 90-minute reperfusion period that followed 4 hours of warm ischemia. Two groups of 32 animals were treated with either 3 mg/kg U-74006F or the vehicle (citrate buffer) alone 30 minutes before ischemia, 90 minutes after ischemia, and immediately before reperfusion. With use of intravital videomicroscopy, the internal luminal diameters of preselected vessels were measured prior to ischemia and during reperfusion. The area that filled with fluorescein was determined at 15-minute intervals for as long as 90 minutes of reperfusion, and contractile function was examined in vitro in an organ bath at that point. In the U-74006F group, after 90 minutes of reperfusion the vessel diameters returned completely to baseline and the diameters of all three categories of vessels at every time point from 10 to 90 minutes of reperfusion had significantly more rapid recovery than the controls. Although some evidence of more rapid fluorescence was noted in the U-74006F group, the two groups did not differ significantly at any time period of reperfusion. In response to tetanic stimulation, the muscles treated with U-74006F had a significantly greater contractile force at all stimulation frequencies than the control muscles. Our findings indicate that pretreatment with U-74006F can effectively decrease the rise of vascular resistance and preserve the contractile function of skeletal muscle during early reperfusion, thereby attenuating ischemia-reperfusion injury.  相似文献   
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OBJECTIVE: To analyse the effect of hospital experience on mortality after subtotal pancreaticoduodenectomy in the Netherlands. DESIGN: Retrospective evaluation. METHOD: Information on hospital mortality and pancreatic resection in 1994 and 1995 in the Netherlands was obtained from the National Medical Register. Subanalysis was carried out of surgical mortality by age and hospital experience. RESULTS: Approximately 50% of the pancreaticoduodenectomies in the Netherlands were performed in hospitals with limited experience (< 5 procedures per year). Hospital mortality was higher in small-volume hospitals than in hospitals with experience (> 25 procedures per year): in 1994 17.2 and 0% and in 1995 14.6 and 2.9%, respectively (p < 0.05). Mortality was higher in patients older than 70 years compared with patients younger than 55 (p < 0.05). CONCLUSION: There was a correlation between mortality after pancreaticoduodenectomy and hospital experience. Therefore these procedures should be performed in centres with experience.  相似文献   
45.
In this paper the case for subsidies for solar energy to counter inefficient pricing practices of electric utilities, hidden subsidies to non-solar fuels and tax law biases are examined. The conclusion reached for two of three regions in the USA in the case of solar energy replacing electricity for hot water heating is that, far from offsetting biases against solar energy, current subsidies reinforce pre-existing biases in favour of the use of solar energy systems.  相似文献   
46.
This study investigated (a) attitudes toward service use among wife caregivers of frail older veterans; and (b) the relationship between those attitudes and service utilization by the wives. The study focused on three sets of attitudinal variables: attitudes towards various kinds of dependencies; individual and family ethos concerning service use; and perceptions of responsibility for care. Respondents were 80 wife caregivers of frail older (age 55+) veterans at a Department of Veterans Affairs Medical Center in a Midwestern state. Most caregivers agreed that it is acceptable to get help with the physical care of the husband and to get help themselves for the emotional strains caused by caregiving. Acceptability of a wife's getting help with the physical care of her husband was a positive predictor of number of services ever used and frequency of in-home service use. Wives' view that help from outside agencies should be used only as a last resort was the strongest and most consistent negative predictor of both number of services ever used and frequency of service use.  相似文献   
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BACKGROUND: Interhospital differences in blood transfusion practice during coronary artery bypass graft (CABG) surgery have been noted, but the underlying issues have not been identified. STUDY DESIGN AND METHODS: Records of 3217 consecutive CABG cases in five university teaching hospitals in 1992 and 1993 were stratified by hospital, type of revascularization conduit, patients' sex, and other factors. Statistical methods were used to compare patient characteristics, transfusion outcomes, and hospital outcomes. RESULTS: Forward two-step logistic regression using patient likelihood of red cell transfusion factors in the first step and the specific hospital in the second step revealed a significant effect of hospital on the delta odds ratios for red cell transfusion. This finding was confirmed by analyses of a highly stratified subset of cases, males in diagnosis-related group 107 (primary cases of coronary bypass without coronary catheterization) who underwent revascularization with venous and internal mammary artery grafts, revealing variations among hospitals from 109 to 457 units of red cells transfused per hundred cases. Corresponding variations in transfusions of all blood components were from 324 to 1019 units by hospital. Variation in red cell transfusion practice among surgeons in the same hospital was not responsible for these interhospital differences. CONCLUSION: The effect of the specific hospital on transfusion practice is attributed to institutional differences that, through reasons of training or hierarchy, become ingrained in hospitals.  相似文献   
48.
The appropriate use of blood transfusions remains variable among health-care institutions and patient populations. Transfusion practices are discussed in this article in relation to medical practice guidelines and utilization review. Specific transfusion practices in the settings of intensive care, orthopedic surgery, and open heart surgery are reviewed. A new, promising approach to improving transfusion outcomes is the use of transfusion algorithms. Transfusion algorithms may prove especially useful if they incorporate point-of-care testing that is both physiologic and patient-specific for transfusion decisions. Transfusion algorithms are discussed and data presented for cardiac surgical adults.  相似文献   
49.
BACKGROUND: Epidemiologic studies are necessary to determine the prevalence of allergic diseases. This varies widely depending on allergen preparations and patients studied. OBJECTIVE: To investigate the prevalence of atopic disease, skin test reactivity, total and specific IgE to common allergens, and other variables in a sample of students from Málaga, southern Spain. METHODS: Three hundred sixty-five students (age 17.9 +/- 1.18) were interviewed by an allergist. Skin prick tests were performed with Dermatophagoides pteronyssinus, Artemisia vulgaris, Plantago lanceolata, Chenopodium album, Olea europaea, Phleum pratense, Parietaria judaica, Cynodon dactylon, Alternaria tenuis, and cat dander. Total and specific IgE to D. pteronyssinus, Olea, and Parietaria were determined. RESULTS: Of all subjects studied, 19.9% suffered from rhinoconjunctivitis, 4.1% rhinoconjunctivitis plus asthma, 3.1% asthma alone, and 0.8% atopic dermatitis; 46.4% had a positive skin test to at least one allergen (28.2% to D. pteronyssinus, 20.4% to Olea, 13.8% to Phleum); and 43% had total IgE > 100 kU/L and 44.7% a family history of atopy. Allergic symptoms were strongly associated with skin test positivities and family allergic history. Patients with asthma or skin prick test positive had higher total IgE values than others (P < .01). There was a significant correlation between specific IgE values and wheal size in skin test. CONCLUSIONS: Our findings confirm the high prevalence of atopic diseases, and the close relationship of skin tests reactivity (or presence of specific IgE) to allergens with symptoms of asthma and rhinitis. The presence of a family history of allergic diseases influences the development of positive skin tests and atopic illness. Dermatophagoides pteronyssinus and pollen of Olea europaea were found to be the most common allergens.  相似文献   
50.
Recent advancements in laparoscopic surgery have made laparoscopic splenectomy possible. We retrospectively compared the outcomes of laparoscopic versus open splenectomy in patients with idiopathic thrombocytopenic purpura (ITP) or beta-thalassemia. From July 1993 to July 1997, 52 patients (ITP, 43 cases; beta-thalassemia, 9 cases) underwent either laparoscopic (30 patients, 9 men, 21 women; average age, 36.9 years) or conventional open splenectomy (22 patients, 5 men, 17 women; average age, 34.3 years). The two groups were similar in terms of sex, age, diagnosis, duration of disease, preoperative platelet count, and spleen size. The mean surgical time, estimated amount of blood loss, duration of postoperative recovery, analgesic usage, and complications were compared between the two groups. Laparoscopic splenectomy was successful in 29 (97%) of the 30 patients. The mean surgical time in the laparoscopy group was longer than in the open splenectomy group (190.6 vs 113.9 minutes, p < 0.01). The laparoscopy group had earlier postoperative oral intake (15.2 vs 52.6 hours, p < 0.01), less usage of analgesics (meperidine 50 mg/unit, 1.1 vs 2.8 units, p < 0.01) and a shorter postoperative hospital stay (4.1 vs 6.8 days, p < 0.01). The estimated blood loss, incidence of accessory spleen, surgical complication rate, and recurrence rate of thrombocytopenia were similar in the two groups. Our findings show that laparoscopic splenectomy in patients with ITP or beta-thalassemia is as safe as the open approach. While laparoscopy required a longer surgical time, the recovery period was shorter, analgesic use was less, and physical discomfort was less severe.  相似文献   
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