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Background  

Whereas testicular metastases are in themselves a rare entity, testicular secondaries from an appendiceal carcinoma have not yet been described. The case also illustrates the diagnostic dilemma of a tumour presenting as epididymo-orchitis.  相似文献   
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Nineteen patients in acute left ventricular power failure following acute myocardial infarction were given support with intraaortic balloon pumping and underwent cardiac catheterization. Hemodynamic response to disastolic augmentation, results of left ventriculography, and observations of selective coronary arteriography were evaluated to determine which patients could survive without operation, which would require operation to survive, and which could be predicted not to survive operation. Of ten patients who underwent operation, three were long-term survivors. Two patients predicted to have a good prognosis without surgery did survive. Of three patients who had been determined to require operation but not undergo it, two died in the hospital and one a month later. The four patients whose conditions were considered inoperable died in the hospital. The results indicate that current methods of predicting the need for corrective surgery are relatively accurate and that the rate of survival in surgically treated patients may be increased.  相似文献   
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Thirty-six patients with variant angins pectoris (VAP) were analyzed to investigate whether the mechanism underlying dysrhythmia is related to coronary occlusion or reperfusion. Fifteen of the 36 patients demonstrated dysrhythmias (42%). Twelve of 15 patients (80%) experienced dysrhythmia prior to the acme of ST-segment elevation (occlusive dysrhythmia), and those of tachyarrhythmia type were characterized by the presence of ventricular premature beats initially isolated, increasing in frequency, and preceding the more malignant forms of dysrhythmias, such as ventricular tachycardia or ventricular fibrillation. The occlusive dysrhythmias included ventricular dysrhythmia (ventricular premature beats, ventricular tachycardia, slow ventricular tachycardia, ventricular fibrillation) in eight patients and conduction abnormalities (second- and third-degree AV block, left posterior fascicular block) in four patients. Thirteen episodes of VAP were fully recorded electrocardiographically. The average time to onset of dysrhythmia, after the beginning of ST-segment elevation, was 4.94 minutes ± 1.52. The duration of the episodes without dysrhythmia was 0.86 minute ± 0.53. The “reperfusion dysrhythmia” occurred in three patients (20%) and was characterized by the appearance of isolated couplets of ventricular premature beats, ventricular tachycardia, or ventricular fibrillation without prodromal ectopic activity. The dysrhythmia occurred in one patient during the resolution of ST-segment elevation and in two patients within seconds of ST-segment normalization. We conclude that the occlusive related dysrhythmias are the most important mechanism in VAP. They are dependent on the duration of the ischemic episode.  相似文献   
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OBJECTIVES: To investigate the relationship of specific nutrients and food items with oral precancerous lesions among tobacco users.
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day-1 ( P < 0.05). Ascorbic acid appeared to be protective against leukoplakia with the halving of risk in the two highest quartiles of intake (versus the lowest quartile: OR = 0.46 and 0.44, respectively; P < 0.10). A protective effect of tomato consumption was observed in leukoplakia and a suggestion of a protective effect of wheat in OSF.
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions.  相似文献   
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RATIONALE AND OBJECTIVES: The purpose of this study was to determine relative rates of missed diagnoses for radiologists as a measure of competence in interpreting chest radiographs. MATERIALS AND METHODS: Cases involving differing interpretations of chest radiographs were collected from January 1994 through December 1999 by faculty (chest and nonchest radiology specialists) in an academic radiology department. A quarterly peer-review process designated cases months after the fact, and anonymously, as no miss or as class I (nondiagnosable), class II (very difficult diagnosis), class III (should be diagnosed most of time), or class IV (should almost always be diagnosed) missed diagnoses. The rates and classes of missed diagnoses were compared among chest faculty and for the nonchest radiology specialists as a group. RESULTS: Chest radiologists read 184,977 studies, and nonchest radiologists read 300,684 studies. Of these, 243 missed diagnoses were classified (classes I and II, 184 cases; class III, 50; and class IV, nine). No difference was detected in the rate of class III and IV misses among chest faculty, but nonchest faculty had significantly more class III (P = .022) and class IV misses (P = .016). CONCLUSION: Random sampling of differing interpretations can yield a relative rate of missed diagnoses for radiologists. No difference was detected in clinically important misses (ie, classes III and IV) among chest radiologists, but a statistically significantly higher rate of seemingly obvious misdiagnoses was found for nonchest specialty radiologists. Potential biases may have influenced this analysis, including disease prevalence, sampling, clinical factors, observer variability, and truth-in-diagnosis.  相似文献   
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