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61.
Angiographic studies of the bronchial and other systemic thoracic arteries were requested by referring physicians in 21 patients, in 18 cases because of hemoptysis. Selective catheterization was carried out in 18 of the 21, and in an additional two patients the bronchial arteries were identified by thoracic aortography. Five examples of effective therapeutic embolization are discussed. Bronchial angiography and embolization appear to be of value in the diagnosis and treatment of hemoptysis.  相似文献   
62.
CONTEXT: We devised a risk appraisal function to assess the hazard of heart failure in persons who are predisposed by coronary disease, hypertension, or valvular heart disease. OBJECTIVE: To provide general practitioners and internists with a cost-effective method to select people at high risk who are likely to have impaired left ventricular systolic function and may therefore require further evaluation and aggressive preventive measures. METHODS: The routinely measured risk factors used in constructing the heart failure profile include age, electrocardiographic left ventricular hypertrophy, cardiomegaly on chest x-ray film, heart rate, systolic blood pressure, vital capacity, diabetes mellitus, evidence of myocardial infarction, and valvular disease or hypertension. Based on 486 heart failure cases during 38 years of follow-up, 4-year probabilities of failure were computed using the pooled logistic regression model for each sex; a simple point score system was employed. A multivariate profile was also produced without the vital capacity or chest x-ray film because these may not be readily available in some clinical settings. RESULTS: Using the risk factors that make up the multivariate risk formulation-derived from ordinary office procedures-the probability of developing heart failure can be estimated and compared with the average risk for persons of the same age and sex. Using this risk profile, 60% of events in men and 73% in women occurred in subjects in the top quintile of multivariate risk. CONCLUSIONS: Using this multivariate risk formulation, it is possible to identify high-risk candidates for heart failure who are likely to have a substantial yield of positive findings when tested for objective evidence of presymptomatic left ventricular dysfunction. The risk profile may also identify candidates who are at high risk for heart failure because of multiple, marginal risk factor abnormalities that might otherwise be overlooked.  相似文献   
63.
An open, multicenter trial of adult myelography was carried out at six centers in 117 patients with iohexol (Omnipaque) 240 mg I/ml and 300 mg I/ml to determine whether there was a difference in visualization or side-effects when a lumbar or cervical approach was used to visualize the areas where disease was suspected. One hundred and thirteen myelograms were analysable. In over 85% of the myelograms with a lumbar approach, visualization of the area injected was excellent or good. Just over half of these were obtained with the intention of visualizing primarily the cervical area, and in 93% of these visualization was good or excellent at that site. In 100% of the cervically injected myelograms, visualization was excellent in the cervical area. Areas more distant from the injections were well visualized in the majority of patients. There was no significant difference overall in visualization with either of the two concentrations of iohexol used. There were 59 side-effects, mostly mild in nature; 40 of them occurred in 50 patients receiving the higher concentration and 19 in 63 patients receiving the lower concentration. The most common side-effect was headache (23 patients). Nystagmus was the only severe side-effect and occurred in only one patient having cervical myelography. The patient made a complete recovery within 36 hours.  相似文献   
64.
65.
Intraspinal cysts: a classification and literature review   总被引:7,自引:0,他引:7  
Advances in radiologic technology have allowed the identification of a variety of cystic lesions of spinal nerve roots. Failure to appreciate the different characteristics of these cysts has led to a confusion in terminology, with different terms often being used to describe the same lesion. In an attempt at clarification, the literature is reviewed and a simplified classification of spinal cysts presented. The distinguishing features of each type of cyst, its investigation, and appropriate treatment are discussed.  相似文献   
66.
Representative chemicals from the long chain alcohols category have been extensively tested to define their toxicological hazard properties. These chemicals show low acute and repeat dose toxicity with high-dose effects (if any) related to minimal liver toxicity. These chemicals do not show evidence of activity in genetic toxicity tests or to the reproductive system or the developing organism. These chemicals also are not sensitizers. Irritation is dependant on chain length; generally, alcohols in the range C6–C11 are considered as irritant, intermediate chain lengths (C12–C16) alcohols are considered to be mild irritants and chain lengths of C18 and above are considered non-irritants. These chemicals are broadly used across the consumer products industry with highest per person consumer exposures resulting from use in personal care products. Margins of exposure adequate for the protection of human health are documented for the uses of these chemicals.  相似文献   
67.
68.
Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816–2373) to 1384 (874–2345) ml (median and range; P<0·05), where the impedance did not change significantly from 140 (92–181) ohms. The volume of the operated leg increased more [from 1129 (824–2373) to 1600 (1090–2837) ml], and the decrease in electrical impedance was also pronounced [137 (125–169) to 83 (69–104) ohms (P<0·001)]. Tissue injury after surgery was indicated by an increase in total creatine kinase (n = 17) and MB isoenzyme of creatine kinase (n = 8) (P<0·05). Myoglobin (n = 8) had increased already during surgery (P<0·05), whereas there was no significant change in the plasma concentration of troponin I (n = 8). In conclusion, tissue injury was reflected by increases in muscle enzymes in plasma. We found an inverse correlation between lower leg electrical impedance and volume, but the deviation in electrical impedance was approximately twice that of the leg volume. Electrical impedance appears to be a useful method for the evaluation of lower leg oedema after distal bypass surgery.  相似文献   
69.
Fourteen patients received 5-iodo-2(1)-deoxyuridine (IdUrd) before surgery for placement of a hepatic arterial catheter. Biopsy specimens were obtained at the time of surgery and incorporation of IdUrd into deoxyribonucleic acid (DNA) in tumor and normal hepatic tissue was measured by HPLC and used as an index of drug selectivity. Over a 3-day intravenous infusion of IdUrd at 1000 mg/m2/day, substitution for thymidine in tumor DNA averaged 3.1%. Normal hepatic DNA contained less than 1% substitution by IdUrd. Arterial delivery of IdUrd increased levels in DNA, whereas modulation with fluorodeoxyuridine produced mixed results. In six patients, flow cytometric analysis showed that the tumor contained a median of 32% of tumor cells that had incorporated IdUrd in 3 days, corresponding to a potential doubling time of only 10 days. Thymidylate synthetase activity in tumors was 20-fold greater than in normal liver tissue, whereas thymidine kinase activity was twofold greater in tumors. These pharmacologic studies encourage further clinical trials of IdUrd as a cytotoxic agent or radiosensitizer.  相似文献   
70.
Bulletin of Environmental Contamination and Toxicology - The herbicide atrazine is heavily applied in the U.S. Midwest to control broadleaf weeds. It enters local streams and rivers through runoff...  相似文献   
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