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991.
Studies were performed to evaluate the effect of unilateral nephrectomy on glycerol-induced acute renal failure in the rat. Normal rats were subjected to either sham uninephrectomy (n = 43) or right uninephrectomy (n = 53). The functional compensation of the remaining kidney was followed after 1 and 2 weeks. Fourteen days after the operation, acute renal failure was induced by injection of 50% glycerol solution to both groups. Uninephrectomised rats developed a lesser degree of renal failure compared to sham-operated rats. Forty-eight hours after glycerol injection, PCr of uninephrectomised rats was 260 +/- 22 mumol/l compared with 338 +/- 26 in sham-operated rats (P less than 0.0125) and CCr in uninephrectomised rats was greater (0.10 +/- 0.01 ml/min vs 0.07 +/- 0.01; P less than 0.025) in sham rats. Uninephrectomised rats had significantly greater recovery of CCr compared to sham rats at 24 h (20.1% +/- 2.3 vs 13.1% +/- 2.2, P less than 0.025) and at 48 h (32.1% +/- 3.3 vs 19.2% +/- 3.3, P less than 0.005) after glycerol injection. FENa was significantly less in uninephrectomised rats: 0.96 +/- 0.16% vs 2.25 +/- 0.05% (P less than 0.025) in sham rats 24 h post glycerol. Urinary excretion of K+ was greater in rats following uninephrectomy compared to sham rats both after 24 h and 48 h post glycerol (P less than 0.01), accompanied by lower plasma potassium (P less than 0.05). A correlation coefficient (r) of 0.793 was observed between urinary potassium excretion rate and percentage recovery of CCr.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
Laparoscopic cholecystectomy (LC) using electrocoagulation was successfully performed in 56 out of 58 selected patients. Cholangiography was performed in 53 patients. Six patients had common duct stones; five were unsuspected preoperatively. After the gallbladder was removed, three patients underwent open common duct exploration. In another five cases, anatomical anomalies were discovered. Cholangiography performed via the cystic duct before any structures are divided can prevent the most serious complication--common duct injury. Cholangiography should be attempted on all patients undergoing LC.  相似文献   
993.
Early changes in the morphology of the gastric mucosa after the skin had been burned were studied using a standardised model in rats. A full thickness burn was inflicted by exposing about 20% of the total body surface area to hot water (99 degrees C) for 10 s. Intragastric acidity was kept at pH 1.0 or pH 7.4 in six experimental groups of eight rats. Rats were subjected to burns with the stomach irrigated at pH 1.0 or pH 7.4. Parallel groups received fluid replacement with a solution of human albumin, and two uninjured groups served as controls. Lesions of the gastric mucosa were measured by planimetry of photographs, and light microscopy was used for histological examination. At an intragastric pH of 1.0, the burned rats developed mucosal erosions covering an average of 13% of the total glandular mucosa; the remaining groups had only minimal mucosal lesions. Erosions of the gastric mucosa after the skin had been burned could be prevented in two ways--either by establishing an alkaline (pH 7.4) milieu in the gastric lumen, or by replacing sufficient fluid to maintain aortic blood pressure at the pre-experiment level. Fluid replacement prevented mucosal erosions even if the intragastric pH was kept at 1.0. Thus both luminal acidity and local tissue blood flow are possible mechanisms for gastric epithelial damage following burns of the skin.  相似文献   
994.
This study reports our experience in 6 cases of acute idiopathic scrotal oedema. Although children were the primary targets, this pathologic condition was also encountered in adults. Specific diagnosis of acute idiopathic scrotal oedema, opposed to other causes of scrotal swelling, is based on history, an objective examination, velocimetric Doppler exam and echography. Correct diagnosis is important in order to avoid unnecessary surgery. We are inclined to consider acute idiopathic scrotal oedema as an allergic disorder and recommend a follow-up within two days.  相似文献   
995.
Despite standards of living and life expectancy amongst the highest in Europe, Switzerland exhibits fairly substantial social inequities in health. As regards male mortality by socio-economic group, these differentials are both marked and independent of cause of death. There is a wealth of information on morbidity and disability supporting the hypothesis that people in lower socio-economic groups tend to age faster and suffer more at younger ages. It is similarly evident that infants of low class mothers, particularly those unwed, underprivileged immigrant, are at excess risk. The Swiss results are of political and scientific interest in that they suggest that the average wealth of a community does not determine health differentials.  相似文献   
996.
997.
An 80-year-old man was evaluated for an epibulbar tumor on a phthisical eye. The initial biopsy diagnosis of the epibulbar tumor was poorly differentiated neoplasm. Exenteration of the phthisical eye and orbital contents showed an extensive pleomorphic adenocarcinoma of the nonpigmented epithelium of the ciliary body with extraocular extension. There was evidence of hyaluronic acid secretion and immunohistochemical staining was strong for vimentin, focal for epithelial membrane antigen and S-100 protein, and weak for neuron-specific-enolase. Electron microscopy demonstrated desmosomes between tumor cells, areas of thick, multilaminar basement membrane production surrounding individual tumor cells, and occasional intracytoplasmic intermediate filaments.  相似文献   
998.
999.
Sodium saccharin, at high doses in the diet, has been reported to cause hyperplasia of the forestomach (squamous portion of stomach), at the limiting ridge in F344 rats, in addition to its potential to induce proliferative effects on the urinary bladder epithelium. We have characterized this hyperplasia of the squamous epithelium of the forestomach at the limiting ridge in F344 and Sprague-Dawley rats given various doses of sodium saccharin for 4 to 95 wk. With increasing doses of sodium saccharin, the limiting ridge of the forestomach showed dose-related morphological changes: basal-cell hyperplasia, early papillary hyperplasia with basal-cell hyperplasia and papillary hyperplasia. Calcium saccharin in Prolab diet caused hyperplasia of the forestomach at the limiting ridge, similar to that caused by sodium saccharin. The severity of hyperplasia was influenced by the type of diet and by the strain of rats. AIN-76A diet without added sodium saccharin caused basal-cell hyperplasia in F344 rats, whereas Prolab, Purina and NIH-07 diets without added sodium saccharin had little or no effect on the forestomach. The effect of AIN-76A diet alone persisted through 95 wk of feeding without any evidence of tumour formation. In Sprague-Dawley rats, which appeared more sensitive to effects on the forestomach than F344 rats, Prolab 3200 and Purina diets without sodium saccharin caused basal-cell hyperplasia in more than half of the treated rats. The forestomach hyperplasia associated with AIN-76A or saccharin administration appears to be mild, limited in extent to the limiting ridge, and not associated with carcinogenesis.  相似文献   
1000.
We studied the spatial frequency characteristics in the upper and lower hemiretina using pattern reversal VECPs. The subjects were 56 normal volunteers ranging in age from 14 to 69 years old. The latency of the first major positive component (P100) of VECPs was measured using checker board pattern stimuli under varying conditions of spatial frequency (112', 56', 28', 14', 7'). For the upper hemiretinal stimuli, the P100 peak latency vs spatial frequencies curve reached minimum at 56' approximately 28' and increased at both lower and higher frequencies. For the lower hemiretinal stimuli, this curve shifted towards lower frequencies. The results suggested that the spatial frequency characteristics between the upper and lower hemiretina were different.  相似文献   
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