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In 570 patients with sporadic primary hyperparathyroidism, the age, sex, symptoms, and preoperative serum calcium values were related to the histopathologic diagnoses, operative findings, and the extent and outcome of parathyroid surgery. Renal stone formation was especially prevalent in younger patients with slight hypercalcemia and parathyroid chief cell hyperplasia, whereas neuromuscular and psychiatric disturbances were overrepresented among older women with higher serum calcium values. Serum calcium concentration was inversely correlated to the proportional incidence of chief cell hyperplasia and positively correlated to the glandular weight of both adenomas and hyperplasias. Glandular size was markedly irregular in chief cell hyperplasia, with increased gland weights of no more than two glands in 78% of patients. During follow-up, for as long as 27 years, normocalcemia was obtained in 91% of patients with adenomas, with failures mainly depending on difficulties in identifying the parathyroid glands. The rate of normocalcemia was lower (80%) among patients with hyperplasia, but an inability to visualize the glands was not a major cause of failure. In patients with hyperplasia with asymmetric and more markedly enlarged glands, it appeared sufficient to remove only the enlarged glands, whereas the findings advocated a subtotal 3- to 3.5-gland resection in patients with more symmetrically or less enlarged hyperplastic glands.  相似文献   
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BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks.  相似文献   
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Organophosphate compounds are cholinesterase inhibitors widely used in agriculture, industry, household products, and even as chemical weapons. Their major mechanism of acute toxic action is the inhibition of acetylcholinesterase, which is responsible for the degradation of the neurotransmitter acetylcholine. An organophosphorus ester-induced chronic neurotoxicity (OPICN) syndrome has been proposed. The OPICN syndrome could result from both long-term exposure to subclinical doses of OPs and after acute poisoning. Development of animal models for the cognitive decline are required and could later help to elucidate the mechanisms involved in this long-term effect on the central nervous system. Previously, we have found performance decrements in a four-trial repeated acquisition spatial task in a water maze. The present study includes two experiments to extend the long-term behavioral effects observed. Rats were injected either once or twice with chlorpyrifos (CPF) and then tested months after in a two-trial repeated acquisition task in a water maze. Our results confirm and extend the long-term behavioral effects of subcutaneous administration of CPF. The two treatments used produced performance decrements that suggest functional central nervous system alterations.  相似文献   
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A retrospective study of 232 bladder tumours with minimum follow-up 5 years is presented. The carcinoma was superficial in 66%, muscle-invasive in 31% and could not be staged in 3%. Primary treatment was mainly transurethral resection for superficial tumour, but was cystectomy or radiotherapy in 22 of 29 T1 G3. Of the superficial tumours, 71% recurred. Progression to higher T stage occurred in 15% of Ta and 29% of T1 tumours, and half of these patients died of bladder cancer. The corrected 5-year survival rates in grades 1, 2A, 2B and 3-4 were 96, 84, 64 and 43%, and in stages Ta, T1, T2 and T3 they were 94, 69, 40 and 31%. All patients with T4 tumour died within 4 years. Among the 45 patients with 40 Gy irradiation + cystectomy, the corrected 5-year survival rate was 83% in superficial and 64% in muscle-invasive tumours, and among the 38 with radical radiotherapy the rates in T1-3 were 46, 36 and 13%. Transurethral resection was successful in most Ta cases. Most T1 tumours were, like T2-4, of higher grade than Ta. Prognosis was worse in T1 than in Ta. After progression to muscle-invasive disease, even during close follow-up the outlook was poor, as poor as for patients with primary muscle-invasive disease.  相似文献   
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