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G K Pande V M Reddy P Kar P Sahni M Berry B N Tandon S Nundy 《BMJ (Clinical research ed.)》1987,295(6606):1115-1117
Between 1976 and 1984, 136 patients with portal hypertension due to extrahepatic obstruction were operated on. Twenty two patients had emergency and 114 elective operations. The operative mortality was 9% and 1%, respectively. Altogether 117 patients (86%) were followed up for from two to 10 years: 17 rebled, none developed encephalopathy or sepsis after splenectomy, and 90% and 75% were alive at five and 10 years respectively. Unlike endoscopic sclerotherapy and treatment with propranolol, operative treatment of variceal bleeding can usually be completed during one admission and carries a low mortality and a fairly low morbidity. Operation seems to be the best form of treatment for poor patients living far from medical facilities in developing countries and may be the treatment of choice in developed countries as well. 相似文献
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Methyl mercury uptake in free cells and different immobilizates of the cyanobacteriumNostoc calcicola has been examined. The general growth of the immobilized cyanobacterial cells could be negatively correlated with methyl mercury uptake. Alginate spheres proved most efficient in terms of uptake rate (0.48 nmol mg protein–1 min–1, 10 min) and total bioaccumulation (10.71 nmol mg protein–1, 1 h) with a bioconcentration factor of 3.3×103. Alginate biofilms showed a faster methyl mercury accumulation rate (0.83 nmol mg protein–1 min–1, 10 min) with a saturation of 10.28 nmol mg protein–1 reached within only 30 min (bioconcentration factor, 3.1×103). Foam preparations with a slow initial uptake approximated biofilms but were characterized by a lower bioconcentration factor (2.8×103). Free cells, in comparison, maintained the initial slow rate of uptake (0.62 nmol mg protein–1 min–1, 10 min), saturating at 30 min (8.81 nmol mg protein–1), and the resultant lowest bioconcentration factor (2.7×103). Cell ageing (30 days) brought a drastic reduction (3-fold) in organomercury uptake by free cells while alginate spheres maintained the same potential. Foam preparations of the same age showed a significant improvement in methyl mercury uptake followed by only a marginal decline in alginate biofilms. Data are discussed in the light of the physiological efficiency and longevity of immobilized cells. 相似文献
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The effect of prostacyclin and colchicine on the fundic gastric mucosa of adult female Wistar rats was investigated in stress (immobilization) and indomethacin induced ulcer models. Under prostacyclin treatment the ulcer index decreased significantly in both ulcer models. This effect was inhibited by colchicine. The nuclear volume of fundic epithelial cells increased significantly after application of either type of ulcerogenic stimulus. Prostacyclin did not influence the nuclear volume changes in stress ulcer, while it prevented this phenomenon in indomethacin-induced ulceration. Following colchicine treatment the nuclear volume decreased in both ulcer models. After combined prostacyclin and colchicine treatment the nuclear shrinkage remained unaltered in stress ulcer, while in indomethacin ulcer the nuclear volume decreasing effect of the separately administered drugs disappeared after combined treatment. The latter phenomenon was interpreted as an antagonistic interaction between prostacyclin and colchicine. 相似文献
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Summary Lipase activity is localized mainly in the cytoplasm of the epithelial cells of all the rat prostatic lobes, and in periacinar stroma of the dorsal prostate; lateral lobe has little enzyme activity. Progesterone (1 and 2.5 mg) causes an increase in lipase activity in the acinar epithelia, periacinar and interfollicular stroma, blood vessels and the mast cells of the ventral prostate. A low dose of estrogen (0.1 g) markedly stimulates and a high dose (5 g) virtually obliterates the activity of the enzyme in the prostatic complex. Following cessation of progesterone therapy the enzyme activity is augmented still further, but near normalization is seen after withdrawal of estrogen. When the two steroids are given conjointly, an estrogenic pattern of morphology is the feature; at the same time there is some suggestion of an antagonism between the two hormones with respect to their effect on the enzyme. Thyroidectomy causes an increase in lipase activity of the complex which is not normalized after thyroxine therapy.Communication no. 1398. Part IX in the series Prostate and endocrines. 相似文献
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1. d-Glucuronolactone reductase, l-gulonolactone oxidase, uronolactonase, dehydroascorbatase, l-gulonate dehydrogenase and l-gulonate decarboxylase have been measured in the tissues of rats fed on diets containing variable amounts of protein. Rats fed on a protein-free or a 2% casein diet for 15 days showed a marked decline in the activities of d-glucuronolactone reductase, l-gulonolactone oxidase, uronolactonase and dehydroascorbatase in the liver, and no change in l-gulonate dehydrogenase and l-gulonate decarboxylase activities in the kidney when compared with rats fed on diets containing 9%, 18% or 25% casein. Giving diets containing 60% or 88% casein to rats did not appreciably alter the activities of uronolactonase, dehydroascorbatase, l-gulonate dehydrogenase and l-gulonate decarboxylase, but inhibited considerably the activities of d-glucuronolactone reductase and l-gulonolactone oxidase in the liver, resulting in decreased synthesis of ascorbic acid. 2. Rats fed on a 25% casein diet showed maximal weight gain, higher tissue reserve of ascorbic acid and higher urinary excretion of both ascorbic acid and glucuronic acid when compared with rats fed on diets containing lower or higher amounts of protein. 相似文献
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