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991.
This study was undertaken to determine the relative effects of morphine and halothane anesthesia on coronary blood flow. Right heart bypass was instituted in 20 dogs by draining the vena cava blood into a cardiotomy reservoir and returning it to the main pulmonary artery. Coronary sinus drainage was measured by a right ventricular cannula. Group I (10 dogs) was sequentially given 0.5, 1, 1.5, 2.0, and 2.5% halothane. Group II (10 dogs) was given 1, 2, 3, 4, and 5 mg per kilogram of morphine intravenously. Arterial pressure, coronary sinus blood flow, cardiac output, arterial pH, Pco2, and Po2 were determined and repeated at each dose level of anesthesia and compared to the control values.Morphine significantly increased coronary flow at 3, 4, and 5 mg/kg without pressure adjustment and at 2 mg/kg after pressure adjustment. Coronary flow with halothane was unchanged from control values except for a decrease at 2.5%. Coronary flow was significantly greater with 3, 4, and 5 mg/kg of morphine than with 1.0 and 1.5% halothane.  相似文献   
992.
Myocardial imaging using technetium 99m stannous pyrophosphate (99mTc-PYP) has been utilized preoperatively and three to five days postoperatively to detect myocardial infarction in 48 patients undergoing aortocoronary bypass grafting, including 7 having valve replacement (5 aortic, 2 mitral) in addition to revascularization. In the total group of patients operated on there were 3 deaths (6%). Preoperatively, 26 patients had unstable angina and 10 had severe left main coronary artery disease. Eleven of the 48 (23%) were women. ECG and enzyme-proved infarctions occurred in 6 of the 48 patients (12%), but the addition of 99mTc-PYP myocardial imaging demonstrated scintigraphic evidence of infarction in 15 patients (31%), including 2 who died in the operating room. The 99mTc-PYP myocardial imaging technique, which has proved safe, simple, and relatively inexpensive in these patients, suggests that the incidence of infarction after coronary bypass operations is somewhat higher than has been previously recognized from just ECG and enzyme changes. This technique also has been of value in helping to exclude myocardial infarction in difficult clinical situations such as postoperative arrhythmias and the postpericardiotomy syndrome.  相似文献   
993.
One hundred fifty-four patients with renovascular injuries were analyzed to gain insight into the mortality, morbidity and indications for immediate nephrectomy versus arterial revascularization. Arterial revascularization is seldom indicated in patients with a normal contralateral kidney who have multiple associated injuries, hilar injuries, long segmental arterial injuries or prolonged renal ischemia. An attempt at renal artery revascularization is justified with bilateral injuries, when only one kidney is present or when a solitary artery injury can be repaired by simple lateral arteriorrhaphy.  相似文献   
994.
The activity of interferons was tested in ultraviolet light-induced skin tumors in mice. After the tumors were well established, they were injected and measured daily for 19 days. Mouse virus type (IF-alpha + IF-beta) and immune (IF-gamma) interferons were injected intralesionally into three groups of test animals and compared with a fourth group which received mock interferon (control). When used separately, virus type and immune interferons did not affect tumor growth; however, we observed regression in tumor size when the two interferons were used in combination.  相似文献   
995.
996.
Twenty-seven reported cases of pericardial diaphragmatic hernia are reviewed and another case is added. This entity may be congenital or traumatic in origin, the latter being more frequent at a ratio of 2:1. All patients except one were male and the mean age at diagnosis was 40 years. The patients were usually symptomatic, the most frequent complaints being of cardiac or respiratory origin. Pneumoperitoneum may be diagnostic although chest roentgenograms and contrast studies may suggest the diagnosis. Computed axial tomography and echocardiography may prove useful in the future. We believe the anterior abdominal approach is preferable to the transthoracic approach in reducing the hernia and repairing the defect because it affords better exposure and easier accessibility to other intraabdominal disease and can easily be converted into a median sternotomy if needed. The stomach and transverse colon became herniated most frequently and in only three cases was a sac found. The defect involves the central leaflet of the diaphragm and primary repair generally results in a good prognosis.  相似文献   
997.
The charts of 26 patients who were referred with a presumptive diagnosis of neoplasms and who were ultimately found to have only tuberculosis were reviewed. Twenty-one patients (81 percent) were born in the United States, and only three patients had a history of exposure to tuberculosis. Most patients had few symptoms, and the average duration of symptoms was 2.8 ± 1.5 months. Classic symptoms of tuberculosis, like fever, hemoptysis, and weight loss, were uncommon. Chest roentgenographic abnormalities were present in 62 percent of the patients. Although some of the patients had undergone nondiagnostic biopsy procedures before referral, none had had skin tests for tuberculosis. Underlying conditions were found in eight patients, and alcoholism was the most common. Laboratory abnormalities were rare with the exception of increased platelet counts, which were found in eight patients. The most common form of tuberculosis was pulmonary (14 patients) followed by lymphadenitis (nine patients). Tuberculosis remains an elusive disease even in countries with advanced medical technology. In some cases, its presentation may suggest the presence of malignancy.  相似文献   
998.
999.
1000.
Twenty-one infants from six to 52 days of age (mean 23.3 days) with osteomyelitis were studied between 1965 and 1977. The etiologic agents were group B streptococcus (8), staphylococcus aureus (6), gramnegative bacilli (4), Streptococcus pneumoniae (1), and unknown (2). Patients with group B streptococcal osteomyelitis were characterized by an uncomplicated neonatal course, single bone involvement with a predilection for involvement of the proximal humerus, and lack of inflammatory signs. In contrast, patients with osteomyelitis due to other organisms frequently had had manipulative procedures predisposing to infection and were more likely to have multiple bone involvement, fever, and leukocytosis at the time of diagnosis. Functional impairment was detected in only one of 17 patients evaluated a mean of 36 months after diagnosis.  相似文献   
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