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81.
Eleven men and 50 women with severe hypothyroidism were studied. All patients had a serum PBI less than 3.0 mug/100 ml, 131I 24 hours uptake less than 13% and a a photomotogram contraction and half relaxation time of 380 msec or more. Before exercise the mean +/- SE heart rate was 68.39 +/- 3.26/min, the PR interval 17.08 +/- 0.37 csec, the QRS voltage (sum of the QRS amplitude in leads I, II and III) 16.44 +/- 0.89 mm (10mm = 1.0 mV) and the T wave amplitude 0.06 +/- 0.15 mm. A significant correlation (p less than 0.05) existed between the PBI values and the QRS voltage. Following exercise there was a significant acceleration of the heart rate (+ 23.39/min, p less than 0.001), shortening of the PR interval (-0.66 csec, p less than 0.02) and T wave elevation (+ 0.40 mm, p less than 0.001). ST segment changes were not observed in any case. Replacement treatment in 7 cases resulted in a significant change in the resting heart rate (+ 11.86/min. p less than 0.025), PR interval (-3.28 mm, p less than 0.025) and T wave height (+ 2.50 mm, p less than 0.01). These findings suggest that exercise may be used in the differentiation between hypothyroidism and coronary heart disease. The theoretical importance of these findings is also discussed. An increase in cardiac energy demands during exercise may be the cause for some of the ECG changes observed on exertion.  相似文献   
82.
Tartrazine (FD&C Yellow No. 5) and other allowed certified color additives may have an exacerbating effect in chronic urticaria and asthma sufferers. In the individual patient the only way to determine their relevance is to administer test doses. By altering doses, timing and substances and by interspacing controls a battery of tests has been developed. Methods of testing for sensitization to food additives and analgesics are described.  相似文献   
83.
All of 16 infants with neonatal meningitis treated during a 30-month period were found to have accompanying ventriculitis at the time of the initial ventricular puncture. Fifteen of these infants were caused by gramm-negative organisms. All infants received antibiotics systemically and intraventricularly via an implanted ventriculostomy reservoir or by direct ventricular injection. Antibiotic concentrations within the ventricular fluid were monitored during chemotherapy; the complications encountered during treatment are discussed. Fifteen infants survived the infection; of these, seven infants were normal at follow-up examinations. In our experience intraventricular chemotherapy as an adjunct to systemic administration of antibiotics has greatly reduced the mortality rate in neonatal meningitis.  相似文献   
84.
A reduction of red cell SA in patients following acute myocardial infarction is reported and the effects of SA-depleted red cells on cardiac index and alveolar capillary blood flow in the dog are described. The mean red cell SA in 26 patients following acute myocardial infarction was 0.021 +/- 0.001 compared with a mean of 0.031 +/- 0.002 mumol./0.1 ml RBC in 12 normal subjects (p less than 0.01). In five dogs injected with neuraminidase, an enzyme which removes SA from the red cell membrane, a 43% decrease in mean cardiac index from 2.3 +/- 0.22 to 1.3 +/- 0.16 (p less than 0.01) occurred. In films of the pulmonary microcircuation the mean widths of typical alveolar capillary beds decreased 42.6% +/- 5% (p less than 0.01). In three other dogs, autotransfusion with SA-depleted stored blood resulted in a 25% decrease in mean cardiac index from 2.0 +/- 0.21 to 1.5 +/- 0.21 (p less than 0.2), and a 21.7% +/- 0.9% (p less than 0.01) decrease in mean widths of typical alveolar capillary beds. We conclude that a reduction of red cell SA follows acute myocardial infarction and that SA-depleted red cells decrease cardiac index and alveolar capillary blood flow in the dogs.  相似文献   
85.
The effects of feeding diest containing either cholesterol (0.24% w/w) or cholestyramine (2.5% w/w) and of fasting on sterol synthesis in the liver, ileum, and lung of both male and female guinea pigs have been studied by measuring the incorporation by tissue slices of 14C-labeled acetate into total digitoninpredipitable sterols. Cholesterol feeding significantly decreased (P less than 0.05) sterol synthesis in the liver, ileum, and lung of the males and in the ileum of females. Cholestyramine feeding stimulated the rate of hepatic sterol synthesis 13-fold but did not significantly affect sterologenesis in the ileum. Sterol synthesis in the lung was significantly increased (P less than 0.05) but to a much lesser extent than in the liver. Fatty acid synthesis in the liver, ileum, and lung was not significantly affected by either cholesterol or cholestyramine feeding. In guinea pigs fasted for 24 hr, sterol synthesis was inhibited in all three tissues, the most pronounced effect occurring in the liver. Only in the lung was fatty acid synthesis significantly decreased (P less than 0.001) by fasting. Cholesterol feeding resulted in increased concentrations of cholesterol in the plasma and liver. Cholestyramine feeding reduced plasma cholesterol concentration by 81% in females and by 64% in males. However, it did not significantly change the tissue cholesterol concentrations. Fasting resulted in a significant increase (P less than 0.05) in plasma cholesterol concentration but did not effect the concentration of cholesterol in the tissues. It was concluded that in the normal guinea pig, the feedback inhibition produced by both cholesterol and also possibly by bile acids suppresses sterol synthesis in the liver to very low rates compared to those in the small intestine, where sterologenesis is not only less sensitive to the cholesterol negative feedback system than that in the liver, but also is not subject to regulation by the bile acid negative feedback system.  相似文献   
86.
Two cases of perforated diverticula of the terminal ileum are presented with a discussion of the literature. Primary resection is the treatment of choice. Asymptomatic diverticula discovered on routine contrast studies should not be managed surgically.  相似文献   
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