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A semi-quantitative right coronary artery score (RCA score) was derived from the ratio of the number of the major left ventricular branches of the right coronary artery to the total of the right coronary and left circumflex arteries, to stratify the extent of perfusion in patients with right coronary artery dominance. Thirty-seven patients with one-vessel coronary disease involving a dominant right coronary artery proximal to the left ventricular branches were selected for study. Thallium scintigraphy was performed after right intracoronary injection in 11 patients, and 26 patients underwent conventional stress thallium scintigraphy (24 exercise thallium and two dipyridamole thallium scintigraphy). Thallium scores of perfusion region size after right intracoronary thallium injection and perfusion defect size in stress thallium studies were quantitated from planar thallium images. Both the RCA score and the regional thallium scores spanned over a wide range. The RCA score (range 0.23-0.85) correlated best with the posterior (70 degrees left anterior oblique view) plus lateral segment (40 degrees left anterior oblique view) thallium score (r = 0.88 and 0.53 for intracoronary and stress thallium studies respectively). It also correlated with the summed thallium scores in the posterior, lateral, apical and inferior segments (r = 0.73 and 0.54 respectively) but not with thallium scores in the apex or inferior segment alone. The proposed RCA score quantitates the variable posterolateral perfusion territory of the right coronary artery, and could stratify the area of myocardium at risk from coronary stenosis in the majority of patients with right coronary dominance.  相似文献   
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We recently diagnosed subcutaneous fat necrosis in a newborn female infant using fine needle aspiration cytology. The neonate had perinatal asphyxia and her mother a difficult labor, but otherwise the neonate was well developed and healthy and within a few days developed well-defined areas of subcutaneous induration all over. On cytologic examination of the aspirated material, many necrotizing fat cells were found with refractile, needle-shaped crystals arranged in a sheaflike or starburst pattern. Subcutaneous fat necrosis of the newborn is uncommon today, and although the histologic findings from excised tissue are known, this appears to be the first case in which the diagnosis was possible from a sample of fine needle aspirate.  相似文献   
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OBJECTIVES: Our purpose was to determine those factors affecting the route of delivery decisions and the effect of delivery route on maternal and newborn outcomes with the macrosomic fetus. Do higher cesarean rates result in improved newborn outcomes? STUDY DESIGN: A 10-year (1985 to 1994) retrospective data set was used to analyze patients with newborns weighing > or = 4536 and 4000 to 4535 gm at two Green Bay hospitals. Patients with newborns weighing 2500 to 3999 gm were similarly analyzed for comparison purposes. Individual and obstetrician group cesarean rates and newborn and maternal outcomes were identified. RESULTS: Cesarean birth rates for the fetus weighing > 4000 gm were low and varied from 12.8% in the low obstetrician cesarean rate group to 24.0% in the high group. Higher obstetrician group cesarean rates did not result in improved newborn outcomes. Newborn morbidity and mortality were very low but significantly higher for cesarean birth newborns. Maternal complications were fairly low with cesarean birth and rare after vaginal delivery. CONCLUSION: Patients with a suspected macrosomic fetus should be given the same opportunity to achieve a vaginal delivery as patients with smaller fetuses.  相似文献   
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HISTORY AND CLINICAL FINDINGS: A 53-year-old patient had a prosthetic valve (St. Jude Medical 25) 9 years ago because of a Staphylococcus aureus endocarditis with severe aortic regurgitation. An initially mild, progressively more severe, aortic regurgitation then developed as a result of an empty paravalvular abscess cavity, requiring another valve replacement. Fever started on the 3rd postoperative day and persisted despite combined treatment with beta-lactam antibiotics and aminoglycoside. INVESTIGATIONS: At first no infectious focus could be identified radiologically or by echocardiography. But transoesophageal echocardiography revealed vegetations in the old abscess cavity. Several blood cultures were negative, while serological tests gave markedly raised antibody titers against Coxiella burnetii. DIAGNOSIS, TREATMENT AND COURSE: Assuming Coxiella burnetii endocarditis the patient was given doxycycline, 2 x 100 mg daily and cotrimoxazole, 1 x 960 mg daily. The fever subsided and the vegetations had disappeared after four weeks. Because of the high risk of recurrence the antibiotic treatment was to be continued for two years. CONCLUSION: Coxiella burnetii should be considered as a possible cause of fever of unknown origin, especially in patients with existing or operated cardiac valvar defects, when endocarditic vegetations have been demonstrated and several blood cultures have been negative.  相似文献   
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