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51.
When should treatment of acute experimental pancreatitis be started?   总被引:7,自引:0,他引:7  
Sodium taurocholate pancreatitis in the rat is a frequently used experimental model for evaluating therapeutical regimes in this disease. It is, however, uncertain when treatment should be started, as the early phase of this experimental model and thus the time when the pancreatitis really develops is unknown. Serum and pancreatic enzymes, as well as pancreatic morphology, were therefore studied 5, 30, and 60 min after induction of sodium taurocholate pancreatitis. It was found that increase in serum enzymes and decrease in pancreatic enzymes and morphological changes characteristic for acute pancreatitis develop as early as 5 and 30 min after induction of pancreatitis. Thus, therapy in this model may be started shortly after induction of acute pancreatitis.  相似文献   
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This study compares the thermal transfer and rewarming characteristics of heated aerosol inhalation (HAI) alone and combined with peritoneal lavage (PEL) or pleural lavage (PLL). Closed-system PEL and PLL are equally efficient at rewarming hypothermic dogs and do so at a rate approximating 6 degrees C/h/m2. Cardiovascular responses to PEL and PLL were similar. Serum electrolytes, protein, Hct, and arterial blood gases were comparable and little changed when compared in prehypothermia and postrewarming periods. HAI alone provides little heat for rewarming; more heat is realized from endogenous metabolism. Nevertheless, HAI's ease of use and possible selective cardiac rewarming characteristics argue for its inclusion with other methods of active rewarming. The use of PEL or PLL is governed by clinical circumstances.  相似文献   
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55.
The main mechanism of possible cardioprotection by estrogens appears to be a direct effect on the vasculature, resulting in an improvement of endothelial function and inhibition of atherogenesis. Numerous observational and experimental studies have demonstrated a positive correlation between estrogens and various biochemical markers surrogating direct vascular effects. In general, most markers are influenced in a similar way by oral and transdermal hormone therapy, although oral therapy may have a faster and more pronounced effect. The main difference between oral and transdermal administration may be confined to markers that are mainly or exclusively produced in the liver. Clinical studies demonstrate that progestogen addition can have an impact on the beneficial estrogen-induced changes of biochemical markers. Concerning the effects of tibolone, inconsistent data have been found. Overall, tibolone-induced beneficial changes on the various biochemical markers appear to be less marked compared with those of hormone therapy. The few data available on the direct effects of androgens on the vascular wall indicate a less favorable action of androgens on biochemical markers than of estrogens. The practical relevance of marker measurements is currently under discussion. Although evidence strongly supports some of these markers as predictors of acute events, it remains to be established whether modifying circulating levels of these markers will influence outcomes.  相似文献   
56.
The authors report on the relationship of early adolescent substance use (up to the time of the 16th birthday) to educational-vocational performance in the early adulthood of 612 African-American urban subjects. Voluminous prospective data were available on the behavior, test performance, and families of 612 urban African-American subjects, from birth up to 7 years of age. Scarcer prospective data were available for school performance during later years of school. Control variables were derived from these data to determine the amount of variance in each dependent educational-vocational outcome variable that was accounted for, independently of the amount of variance accounted for by early substance use. (American Journal on Addictions 1994; 3:325–336)  相似文献   
57.
Background Nowadays, liver resection is a routine operative procedure in surgical centers, and strategies must be aimed at avoiding additional risk factors. Extrahepatic isolation of portal vein, hepatic artery and hepatic duct, as well as lymphadenectomy of the liver hilum are generally accepted steps of liver resection, even for metastatic and benign indications. Our primary aim was to analyze the feasibility, blood loss, blood transfusion requirements, incidence of complications, and outcome using the approach for intrahepatic devascularization leaving the extrahepatic hilus untouched. Materials and methods Thirty-eight consecutive patients with resection for metastases and benign liver tumors were selected. After hilar examination, the extrahepatic structures remain intact, and during parenchyma dissection, the whole right or left or the appropriate bi-segmental pedicle is isolated intrahepatically and then transected using a stapler device. Results The used technique was feasible in all cases, and no intra- or postoperative surgical complications were observed. To date, no tumor recurrence was found in the hilum during the follow-up period. Conclusion The intrahepatic pedicle stapling technique appears to be feasible and safe in liver resection. Hilar dissection can, thus, be avoided in liver metastasis and benign liver tumors.  相似文献   
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Fluoroscopy is the most common tool for the intraoperative control of long-bone fracture reduction. Limitations of this technology include high radiation exposure for the patient and the surgical team, limited visual field, distorted images, and cumbersome verification of image updating. Fluoroscopy-based navigation systems partially address these limitations by allowing fluoroscopic images to be used for real-time surgical localization and instrument tracking. Existing fluoroscopy-based navigation systems are still limited as far as the virtual representation of true surgical reality is concerned. This article, for the first time, presents a reality-enhanced virtual fluoroscopy with radiation-free updates of in situ surgical fluoroscopic images to control metaphyseal fracture reduction. A virtual fluoroscopy is created using the projection properties of the fluoroscope; it allows the display of detailed three-dimensional (3D) geometric models of surgical tools and implants superimposed on the X-ray images. Starting from multiple registered fluoroscopy images, a virtual 3D cylinder model for each principal bone fragment is constructed. This spatial cylinder model not only supplies a 3D image of the fracture, but also allows effective fragment projection recovery from the fluoroscopic images and enables radiation-free updates of in situ surgical fluoroscopic images by non-linear interpolation and warping algorithms. Initial clinical experience was gained during four tibia fracture fixations that were treated by LISS (Less Invasive Stabilization System) osteosynthesis. In the cases operated on, after primary image acquisition, the image intensifier was replaced by the virtual reality system. In all cases, the procedure including fracture reduction and LISS osteosynthesis was performed entirely in virtual reality. A significant disadvantage was the unfamiliar operation of this prototype software and the need for an additional operator for the navigation system.  相似文献   
60.
Myocarditis is a major cause of end-stage heart failure and is responsible for up to 10% of cases of idiopathic dilated cardiomyopathy (IDC). Worldwide, approximately 45% of all heart transplants are performed for IDC and up to 8% for myocarditis. Early reports suggested that survival after transplantation for myocarditis was poor and patients had an increased risk of rejection. More recently, larger case series suggest that overall survival after transplantation for myocarditis is similar to survival after transplantation for other causes. However, certain disorders, including cardiac sarcoidosis and giant cell myocarditis (GCM), require heightened surveillance for post-transplantation disease recurrence. We present the case of a 42-year-old man with recurrence of GCM 8 years after transplantation and review the literature on the role of cardiac transplantation for patients with myocarditis.  相似文献   
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