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排序方式: 共有2550条查询结果,搜索用时 31 毫秒
961.
962.
BACKGROUND: Chronic idiopathic intestinal pseudo-obstruction, a syndrome of ineffectual motility due to a primary disorder of enteric nerve or muscle, is rare. AIMS: To determine the clinical spectrum, underlying pathologies, response to treatments, and prognosis in a consecutive unselected group of patients. METHODS: Cross sectional study of all patients with clinical and radiological features of intestinal obstruction in the absence of organic obstruction, associated with dilated small intestine (with or without dilated large intestine), being actively managed in one tertiary referral centre at one time. RESULTS: Twenty patients (11 men and nine women, median age 43 years, range 22-67) fulfilled the diagnostic criteria. Median age at onset of symptoms was 17 years (range two weeks to 59 years). Two patients had an autosomally dominant inherited visceral myopathy. Major presenting symptoms were pain (80%), vomiting (75%), constipation (40%), and diarrhoea (20%). Eighteen patients required abdominal surgery, and a further patient had a full thickness rectal biopsy. The mean time interval from symptom onset to first operation was 5.8 years. Histology showed visceral myopathy in 13, visceral neuropathy in three, and was indeterminate in three. In the one other patient small bowel motility studies were suggestive of neuropathy. Two patients died within two years of symptom onset, one from generalised thrombosis and the other from an inflammatory myopathy. Of the remaining 18 patients, eight were nutritionally independent of supplements, two had gastrostomy or jejunostomy feeds, and eight were receiving home parenteral nutrition. Five patients were opiate dependent, only one patient had benefited from prokinetic drug therapy, and five patients required formal psychological intervention and support. CONCLUSIONS: In a referral setting visceral myopathy is the most common diagnosis in this heterogeneous syndrome, the course of the illness is usually prolonged, and prokinetic drug therapies are not usually helpful. Ongoing management problems include pain relief and nutritional support. 相似文献
963.
Glucose transport activity ([3H]D-glucose uptake) in liver sinusoidal membrane vesicles (SMVs) from hyperthyroid rats was significantly higher than that from euthyroid controls (2.1-times increase in V(max) with K(m) unchanged at approximately 18 mM), associated with increased GLUT2 expression. In contrast, glucose transport V(max) into SMVs from hypothyroid rats was reduced to 0.75-times that of euthyroid controls, associated with a reduced GLUT2 abundance. GLUT1 expression in SMVs was unaffected by changes in thyroid status. GLUT2, but not GLUT1 abundance on the blood-facing membrane of liver cells is sensitive to changes in thyroid status and these changes in transporter expression directly correlate (r = 0.96) with altered glucose transport activity. 相似文献
964.
965.
PJ Coleman GM McQuillan LA Moyer SB Lambert HS Margolis 《Canadian Metallurgical Quarterly》1998,178(4):954-959
Recurrence is a common sequela of Clostridium difficile-associated diarrhea (CDD) and may increase morbidity, costs, and treatment-related antimicrobial resistance. Because recurrent CDD (RCDD) frequently occurs very soon after an initial episode, our goal was to determine the risk factors for early RCDD (occurring < or = 45 days after the initial episode). We conducted a case-control study, comparing 13 patients with early RCDD (case patients) with 46 patients who had only one CDD episode (control patients) at Centre Hospitalier Angrignon (Québec) during January 1993 through November 1994. Risk factors for early RCDD included a history of chronic renal insufficiency, a white blood cell count of > or = 15 x 10(3)/mm3, and community-acquired diarrhea with the first CDD episode. For seven of eight case patients, C. difficile strains from the first and second CDD episodes were identical, suggesting that relapse is more common than reinfection. These results suggest that treatments should be directed at preventing relapses in patients at high risk for early RCDD. 相似文献
966.
967.
968.
YL Chang HS Sohn KC Chan CD Berdanier JL Hargrove 《Canadian Metallurgical Quarterly》1997,127(7):1279-1283
The influence of dietary protein on blood coagulation tests was evaluated in BHE/cdb rats. Three experiments were conducted in order to compare effects of diets with low (8 g/100 g diet) or high (38 g/100 g diet) protein, to establish values for coagulation tests at intermediate (12-30 g/100 g diet) concentrations of dietary protein, and to compare feeding identical quantities of diets with 8 g protein/100 g diet vs. 18 g protein/100 g diet. After 4 wk of feeding the semipurified diets, bleeding time exceeded 15 min in the groups fed low protein diets, compared to a range of 3-6 min for the groups fed high protein diets. Several in vitro tests of coagulation were abnormal in the rats fed low protein diets. For example, prothrombin time averaged 27 +/- 8 s in rats fed 8 g protein/100 g diet plus beef tallow, but 17 +/- 1 s in rats fed 38 g protein/100 g diet plus tallow. The coagulation deficit in rats fed low protein was not affected by fat source (tallow vs. menhaden oil), but fibrinogen was elevated in rats fed diets with menhaden oil. Conversely, no differences in coagulation tests were observed among rats fed 12-30 g protein/100 g diet. Bleeding times ranged from 7 to 9 min, and prothrombin time was 17-18 s. Significant differences in plasma fibrinogen concentration and prothrombin time were observed in rats fed 8 vs. 18 g protein/100 g diet at a fixed rate of 6 g/100 g body weight. Platelet and blood cell numbers were unaffected by dietary protein. The evidence for multiple deficits in the coagulation system suggests that hepatic function in BHE/cdb rats may become impaired when the rats are fed low protein diets of the composition used here. 相似文献
969.
FJ van Spronsen Y Thomasse GP Smit JV Leonard PT Clayton V Fidler R Berger HS Heymans 《Canadian Metallurgical Quarterly》1994,20(5):1187-1191
Hereditary tyrosinemia type I (McKusick 27670) is a heterogeneous disease with poor prognosis, yet there are few reports of the long-term prognosis. It is therefore difficult to decide on the treatment for individual patients. We have conducted an international survey of patients with tyrosinemia type I and examined the probability of survival on dietary treatment and the causes of death in 108 patients with tyrosinemia type I. The survival after the onset of symptoms varied with the age at onset; the earlier the symptoms developed the poorer the outlook. Liver failure and recurrent bleeding (67%), hepatocellular carcinoma (17%) and the porphyria-like syndrome with respiratory failure (10%) were the most common causes of death. The 1- and 2-yr survival probability after the onset of symptoms in patients in whom symptoms developed before 2 mo, between 2 and 6 mo and after 6 mo were 38%/29%, 74%/74% and 96%/96%, respectively. On the basis of these survival rates, a new classification--which is important with respect to choices in treatment--is proposed: very early (onset of symptoms < 2 mo), early (2 to 6 mo) and late presenting form (> 6 mo). 相似文献
970.
HA Tissot van Patot JA Leusink J Roodenburg BM de Jongh HS Lau S de Boer A de Boer 《Canadian Metallurgical Quarterly》1996,18(5):171-177
BACKGROUND: Selective decontamination of the digestive tract (SDD) with non-absorbable antibiotics was extensively used at intensive care units (ICU) in Europe to prevent nosocomial infections in critically ill patients. After three recent meta-analyses in which it was demonstrated that SDD did not influence hospital stay and mortality in these patients several ICU's decided to stop the routine use of SDD. OBJECTIVE: To examine the effects of the cessation of SDD on nosocomial infections, mortality and hospital stay at an ICU in post-operative patients. DESIGN: Retro- and prospective follow-up. PATIENTS: Post-operative patients with mechanical ventilation (MV) for > or = 5 days at an ICU were included. The retrospective group (SDD group) comprised of 138 patients (mean age 66, range 10-91; 78% male) and the prospective group (non-SDD group) of 142 patients (mean age 67 range 18-85; 65% male). The SDD regime consisted of colistin, tobramycin and amphotericin B. Cessation of the SDD was accompanied by a shortening of the routine intravenous cefuroxime prophylaxis. RESULTS: There was a nonsignificant increase from an average 21 to 23 days ICU stay in the non-SDD group when compared with the SDD group (p > 0.05). Of the 280 patients 97 (35%) died on the ICU. The risk of death was lower in the non-SDD group (adjusted hazard ratio 0.7 with 95% Cl 0.5-1.1). There was a trend towards an increase in infections as a cause of death in the non-SDD group (38% of the ceased patients versus 20% in the SDD group) (p > 0.05). The incidence of respiratory tract infection (per 1000 person days) was 80 (95% Cl 48-113) in the non-SDD group versus 19 (95% Cl 8-22) in the SDD group (adjusted hazard ratio 4.5 (95% Cl 2.9-7.1)). CONCLUSION: The cessation of the routine application of SDD in post-operative patients mechanically ventilated for 5 days or more did nod adversely affect survival nor increased length of stay at the ICU. There may have been a shift to infections as a cause of death after cessation of SDD. 相似文献