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991.
992.
993.
Chronic nonspecific diarrhea (CNSD) is the most common cause of prolonged diarrhea without failure to thrive. Although it is most commonly seen from ages 6 to 36 months, CNSD may persist until 54 months of age. Forty-four patients with this syndrome had complete dietary histories, and were divided into four groups on the basis of their intakes and responses to its modification. Each of the four groups had significantly less fat in their diet at the time of presentation than did ten non-CNSD patients (P less than .005) presenting similarly. In three of the groups, daily fat consumption was increased, irrespective of the adequacy of their initial intakes. In all 38 patients in these groups, this dietary modification was associated with the resolution of symptoms. The fourth group, with initially normal dietary fat ingestion, did not respond to dietary therapy. The overall success rate of the regimen in this patient population was 82%. Carbohydrate, fiber, and caloric contents of the diets did not appear to play as significant a role as fat intake.  相似文献   
994.
Four infants are reported who manifested severe alimentary bleeding associated with evidence of massive acute hookworm infestation. The need to remember this parasite as a possible cause of melaena in infants in areas where it is endemic is stressed, as treatment is simple and effective.  相似文献   
995.
996.
Diurnal variation of plasma aldosterone and cortisol concentration in man was studied in 13 anephric subjects and 7 normal subjects. All subjects were ambulatory and active throughout the study except during an 8-hour sleep period. Six anephric subjects received Kayexalate (sodium polystyrene sulfonate) during the studies to prevent potassium accumulation and increase in plasma potassium concentration. Diurnal variation of plasma aldosterone concentration with peak and nadir concentrations at 12:00 noon and 12:00 midnight respectively was demonstrated in the studies on normal subjects. Changes in plasma aldosterone concentration were not significantly correlated with changes in plasma concentration but were highly correlated with changes in PRA (P less than 0.001). There was a highly significant correlation between plasma aldosterone and potassium concentration in the anephric subjects studied without Kayexalate administration (P less than 0.001). In the anephric subjects who received Kayexalate, plasma aldosterone and potassium concentration remained stable, and no correlation could be demonstrated. No diurnal variation of plasma aldosterone concentration could be demonstrated in either group of anephric subjects, whereas plasma cortisol concentration varied as in the studies on normal subjects. Conclusion. Diurnal variation of plasma aldosterone concentration is dependent on continued stimulation by the renin-angiotensin system. Loss of this stimulation has no demonstrable effect on the diurnal variation of plasma cortisol concentration.  相似文献   
997.
998.
An epidemiological survey of 411 patients over a period of five and a half years is analysed. There were no yearly trends but there was a slight increase in the number of female burns during the survey. There were 293 males, 71.3 per cent and 118 females, 28.7 per cent. The majority of the burns occurred in the younger age groups and reflect the cause of the injury. Approximately one-half of the injuries were burns of less than 10 per cent and three-quarters were of less than 20 per cent. The most extensive burns were caused by petrol and clothes fires. Predisposing conditions were present in 23.8 per cent of the patients, with alcohol abuse figuring prominently. Epilepsy was present in 2.7 per cent of the patients. The major predisposing conditions, causes and complications of the burn injuries are discussed. Burn infection occurred in 18.2 per cent of the patients and septicaemia in 3.5 per cent. There was a mortality rate of 8.3 per cent and the average length of hospital stay was 22.9 days. While these burns are mainly preventable it is difficult to see how this can be fully achieved.  相似文献   
999.
Doppler ultrasound was used to study 120 legs of 106 patients with suspected deep vein thrombosis (DVT) or pulmonary embolism. Venography was subsequently performed in all. DVT was confirmed by venography in 44 legs and was confined to the calf in 10 of these. Ultrasound detected three calf thromboses and 29 out of 34 more extensive thromboses. Of five undetected thrombi that were proximal to the calf one was associated with partial occlusion and four with extensive collateral circulation. Of the 76 limbs without venographic evidence of thrombosis 21 were thought to have DVT by ultrasound; 18 of these false-positive results could be attributed to external compression of veins, two to excessive tenderness precluding adequate examination; and in one no explanation was found. This test gives more accurate results than judging by clinical signs alone, but users must be aware of its limitations and, particularly, the causes of false-positive and false-negative results.  相似文献   
1000.
Neurones in the substantia nigra of the rat, anaesthetized with urethane, are inhibited both by electrical stimulation of the ipsilateral caudate nucleus and by iontophoretically applied gamma-aminobutyric acid (GABA). Iontophoretically applied picrotoxin reversibly blocks both of these inhibitory responses. These results are consistent with the hypothesis that GABA is the transmitter released by the inhibitory striato-nigral pathway.  相似文献   
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