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991.
Airway responsiveness to histamine, substance P, methacholine and bilateral electrical vagal stimulation was assessed in capsaicin-treated and control guinea pigs. In animals treated with capsaicin (50 mg/kg s.c.) 7 days before experiments, airway responsiveness to histamine, substance P and vagal stimulation was significantly reduced but responsiveness to methacholine was unchanged. The findings suggest that histamine and substance P, but not methacholine, require capsaicin-sensitive sensory afferent nerves for part of their actions.  相似文献   
992.
The effect of caffeine consumption on mortality was evaluated in a historical cohort study of 10,064 diagnosed hypertensive individuals participating in the Hypertension Detection and Follow-up Program from 1973 to 1979. Total caffeine intake level from beverages (coffee and tea) and certain medications, was estimated at the 1-year visit. No evidence was found supporting an association between increased level of caffeine consumption and increased all-cause mortality or cardiovascular disease mortality during the following 4 years. Cigarette smoking was significantly associated with mortality; the association being more pronounced among non- and low-caffeine consumers for all-cause mortality and among non-caffeine consumers for all cardiovascular mortality except cerebrovascular mortality.  相似文献   
993.
Using the Farnsworth-Munsell 100-hue test, investigations were carried out in 14 patients with subtoxic to toxic serum concentrations of digoxin (greater than 2.0 ng/ml) and 13 patients with subtoxic to toxic serum concentrations of digitoxin (greater than 30 ng/ml), in order to detect color vision deficiencies related to serum levels of digitalis. As compared to the control group (n = 24) the total error scores were significantly increased for both glycosides and all serum level ranges. No evidence was found indicating that digoxin and digitoxin influence color vision differently. The FM 100-hue test indicated definite improvements in the digoxin group within one day of discontinuing the glycosides, while the digitoxin group only started to normalize a week later. The results are discussed, taking the different pharmacokinetics of the two digitalis glycosides into account.  相似文献   
994.
Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.  相似文献   
995.
996.
997.
Long lasting occupational exposure to asbestos dust may cause skin corns, benign pleural effusion, hyaline plaques of the parietal pleura, diffuse thickening of the pulmonary pleura, and asbestosis, i.e. diffuse interstitial pulmonary fibrosis. Malignant disorders include lung cancer and mesothelioma of the pleura, peritoneum and pericardium. In general, many years elapse from first exposure to the appearance of symptoms. Almost all these diseases are the result of dusty working conditions more than 20 years ago. In spite of the fact that the general public is invariably exposed to small amounts of the material, asbestos is not a public health problem. Even living in a building containing sprayed asbestos is calculated to produce a lifetime risk of death which is negligible. There is no evidence to indicate that ingested asbestos fibres represent a major health problem.  相似文献   
998.
We evaluated the effect of glycated albumin on phenytoin protein binding in 36 elderly (age range 63-94 yrs) patients with type II diabetes mellitus (DM) under diet management. Serum was spiked with 15 mg/L phenytoin and incubated. A serum ultrafiltrate was obtained from each sample for determining total and free phenytoin concentrations. Glycated hemoglobin was determined by boronate-affinity chromatography, and glycated albumin was separated from nonglycated fractions with boronate-agarose gel. Glycated hemoglobin in the study group ranged from 4.3-14.6% (mean 7.8 +/- SD 2.1%) and glycated albumin ranged from 3.7-12.5% (7.4 +/- SD 2.6%). We observed no correlation between glycated albumin and the percentage of free phenytoin (r2 = -0.14; p = 0.419). The concentration of nonglycated albumin ranged from 0.66-4.28 g/dl (mean 3.45 +/- 0.67 g/dl) and was calculated from measured total and glycated albumin concentrations. A correlation between the free fraction of phenytoin and nonglycated albumin was not demonstrated (r2 = 0.22, p = 0.22). In addition, a correlation was not observed between total glycated albumin and the free fraction of phenytoin (r2 = -0.095; p = 0.58). We conclude that elderly patients with type II DM under diet control do not have significant alterations in phenytoin protein binding. The use of total serum phenytoin levels therefore appears appropriate for determining phenytoin dosages in elderly patients with well controlled type II DM.  相似文献   
999.
F W Eigler  N Rohm 《Der Chirurg》1990,61(3):149-154
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1000.
G F Coppa  K Eng 《Surgery》1988,104(5):853-858
During a 24-month period, 350 patients were prospectively studied in an effort to determine the perioperative factors in the development of infections after colon and rectal resections. All patients received standard mechanical bowel preparation; perioperative parenteral cefoxitin (group A) or preoperative oral neomycin and erythromycin, in addition to perioperative cefoxitin (Group B), were also given. Both groups were comparable with respect to age, sex, associated diseases, and primary diagnosis. Wound infections developed in nine of 169 (5%) group B patients and in 15 of 141 (11%) group A patients. Stratification by type of operative procedure revealed that the rectal resections involved the highest rate of infection in group A (22%) and in group B (11%). In patients requiring intraperitoneal colon resection, the rates of wound sepsis were similar (3% in both groups). Analysis of length of operation revealed that in operations lasting 215 minutes or more the infection rate was 12%; in those lasting less than 215 minutes the rate was 4%. Patients with rectal resection and operative times of 215 minutes or more had a wound infection rate of 19% compared to 2% (p less than 0.05) in those with shorter nonrectal operations. Group B patients with the longer rectal operations had lower infection rates (11%) than group A patients (27%), while there was no difference among those who had shorter operations. Intra-abdominal abscesses (p less than 0.01) and anastomotic dehiscence (p less than 0.05) were also significantly reduced in group B patients. Postoperative wound infection is associated with length of operation and location of colon resection and can be significantly lowered by a combination of oral and parenteral antibiotics.  相似文献   
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