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41.
Occult cardiac lymphoma presenting with cardiac tamponade   总被引:1,自引:0,他引:1  
Subxiphoid pericardiostomy is the procedure of choice for treatment of a pericardial effusion with tamponade. We report a case in which this procedure not only failed to reveal the presence of an occult malignancy, but also resulted in a recurrent symptomatic effusion.  相似文献   
42.
One hundred seventeen consecutive patients undergoing repeat percutaneous transluminal coronary angioplasty (PTCA) were studied to assess procedural success and recurrent restenosis rates. Clinical, anatomic and procedural variables were examined as predictors of recurrent restenosis using stepwise logistic regression analysis. Primary success was achieved in 114 patients (97.5%). One patient (0.8%) died after acute occlusion. No other in-hospital complications were encountered. After a mean follow-up interval of 218 +/- 160 days, 72 of 114 successfully dilated patients (63%) remained angina free. There were no late deaths. Three patients (2.6%) experienced a late myocardial infarction. Follow-up arteriography was performed in 100 patients (88%), of whom 32% had recurrent restenosis (greater than 50% luminal diameter narrowing). On univariate analysis, the presence of 3 clinical variables at repeat PTCA was associated with significantly higher recurrent restenosis rates compared with their absence, that is, unstable angina (48 vs 20%, p = 0.003), diabetes (61 vs 26%, p = 0.003) and hypertension (46 vs 18%, p = 0.003). Patients with recurrent restenosis had a shorter interval between first and second PTCA compared with those who remained patent (136 +/- 116 vs 214 +/- 163 days, p = 0.018). Multivariate analysis confirmed unstable angina, diabetes and hypertension as independent predictors of recurrent restenosis. Repeat PTCA may be performed for restenosis with a high likelihood of success and low incidence of complications. The rate of recurrent restenosis is similar to that reported for initial angioplasty. Patients with unstable angina, diabetes and hypertension appear to be at higher risk for recurrent restenosis.  相似文献   
43.
Two hundred and thirteen patients were studied in a double-blind trial of cimetidine versus placebo in the treatment of acute upper gastrointestinal haemorrhage. One hundred and six patients were randomly allocated to receive cimetidine and 107 to receive placebo. There was no significant reduction in transfusion requirements, incidence of further haemorrhage, length of stay in hospital, or mortality in the treated group. There was no subgroup of patients with acute upper gastrointestinal bleeding which appeared to benefit from treatment with cimetidine.  相似文献   
44.
Recommendations for the clinical use of probiotics were published after a Yale University Workshop in 2005. A similar workshop was held in 2007, and the recommendations were updated and extended into other areas. The recommendations are graded into an "A," "B," "C" or no category based on the expert's opinion and review by the workshop participants. An "A" recommendation is made for acute childhood diarrhea, prevention of antibiotic-associated diarrhea, preventing and maintaining remission in pouchitis, and in an immune response for the treatment and prevention of atopic eczema associated with cow's milk allergy. The group maintained several "B" recommendations in other areas of treating inflammatory bowel disease and irritable bowel syndrome. Although there are significant studies in the "B" group, most "B" recommendations did not reach an "A" level because of some negative studies or a limited number of studies. Many reports in the "C" recommendations were significant but fell short of receiving stronger ratings because of the size of reported patient studies, and also the factors that limited categories to the "B" rating.  相似文献   
45.
Many patients admitted to hospital with heart failure have preserved left ventricular (LV) systolic function. The incidence of isolated diastolic dysfunction as a cause of such admission remains unclear. We aimed to examine diastolic function in unselected admissions from the community with heart failure using the European Study Group on Diastolic Heart Failure (ESGDHF) Doppler-echocardiographic indices of diastolic dysfunction. Primary heart failure was confirmed in 210 of 309 sequential admissions with suspected heart failure. Doppler echocardiography was used to assess left ventricular ejection fraction, wall thickness and parameters of diastolic function including E:A ratio, E-wave deceleration time and isovolumic relaxation time. Of 210 patients studied (118 female), ejection fraction was <45% in 111, leaving a population of 99 with preserved systolic function. We excluded those with significant valvular disease, leaving 56 patients (mean age=77 years) with an ejection fraction >45% and no other relevant abnormality. Twenty were in atrial fibrillation. E-wave deceleration time was >280 ms in 42%. E:A was reversed in 30 of 36 patients in sinus rhythm, but only seven met the ESGDHF criterion of E:A<0.5. Isovolumic relaxation time was >105 ms in 38%. Wall thickness was increased in 75% of cases. The ESGDHF Doppler-echocardiographic criteria for diastolic heart failure were fulfilled in 43%. In clinically confirmed heart failure, 27% of patients had preserved systolic function and no significant valvular disease. Only 43% of this group had confirmed diastolic heart failure by these ESGDHF criteria. The pathophysiological basis of the syndrome in the remaining 57% remains unclear.  相似文献   
46.
47.
Dietary modification is central to obesity treatment. Weight loss diets are available that include various permutations of energy restriction, macronutrients, foods, and dietary intake patterns. Caloric restriction is the common pathway for weight reduction, but different diets may induce weight loss by varied additional mechanisms, including by facilitating dietary adherence. This narrative Review of meta-analyses and select clinical trials found that lower-calorie diets, compared with higher-calorie regimens, reliably induced larger short-term (<6 months) weight losses, with deterioration of this benefit over the long term (>12 months). Few significant long-term differences in weight loss were observed for diets of varying macronutrient composition, although some regimens were found to have short-term advantages (e.g., low carbohydrate versus low fat). Progress in improving dietary adherence, which is critical to both short- and long-term weight loss, could result from greater efforts to identify behavioral and metabolic phenotypes among dieters.  相似文献   
48.
49.
Epithelial–mesenchymal transition (EMT) is thought to be an important, possibly essential, component of the process of tumor dissemination and metastasis. About 20%–30% of Hras mutant mouse skin carcinomas induced by chemical initiation/promotion protocols have undergone EMT. Reduced exposure to TPA-induced chronic inflammation causes a dramatic reduction in classical papillomas and squamous cell carcinomas (SCCs), but the mice still develop highly invasive carcinomas with EMT properties, reduced levels of Hras and Egfr signaling, and frequent Ink4/Arf deletions. Deletion of Hras from the mouse germline also leads to a strong reduction in squamous tumor development, but tumors now acquire activating Kras mutations and exhibit more aggressive metastatic properties. We propose that invasive carcinomas can arise by different genetic and biological routes dependent on exposure to chronic inflammation and possibly from different target cell populations within the skin. Our data have implications for the use of inhibitors of inflammation or of Ras/Egfr pathway signaling for prevention or treatment of invasive cancers.  相似文献   
50.
Fifteen patients presented during a four-year period with a pseudothrombophlebitis syndrome, subsequently confirmed arthrographically as being due to popliteal cyst rupture. Initially the majority of patients (73%) were erroneously diagnosed as having calf vein thrombosis, and were anticoagulated for periods of three to ten days. Clinical differentiation from venous thrombosis was usually impossible. Contrast arthrography was the definitive diagnostic investigation, revealing popliteal cysts in all patients, and an active synovial leak into the calf in 13 cases (87%). The mean delay in performing arthrography was 5.3 days, the procedure usually being performed after normal contrast venography. Doppler and isotope venography yielded misleading or equivocal results (42%) delaying diagnosis, and prolonging periods of potentially dangerous anticoagulation. We suggest that the marked overlap in the emergency presentation of popliteal cyst rupture and calf vein thrombosis mandates the aggressive use of arthrography combined with venography in all patients presenting with a painful swollen leg.  相似文献   
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