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Summary. α-interferon (α-IFN) has been used to treat chronic non-A non-B hepatitis in thalassaemic patients with response rates from 45% to 83%. Unfortunately, treatment with α-IFN is associated with side-effects which have a negative effect on the quality of life of the patient. Therefore it would be useful if we could distinguish in advance those patients who would benefit from such therapy from those who would not. In the present study we found that the modification of lymphocyte subsets 20 h after the administration of the first dose of α-IFN revealed that relative numbers of T helper lymphocytes (CD4+) increased in three non-responding patients and decreased in five responding patients, whereas those of T suppressor lymphocytes (CD8+), and natural killer cells (CD57+. CD16+) decreased in non-responding patients and increased in responding patients. Therefore analysis of the lymphocyte subsets CD4, CD8, CD57 and CD16 before and 20 h after the administration of α-IFN can be used to predict the clinical response to treatment with α-IFN.  相似文献   
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OBJECTIVES: IgM memory B cells that are responsible for the protection against infections by encapsulated bacteria, require the spleen for their generation and/or survival. Since the association between inflammatory bowel disease and functional hyposplenism is well described, our aim was to verify whether IgM memory B cells mirror the reduced splenic function in Crohn's disease and ulcerative colitis patients. METHODS: Peripheral blood samples were obtained from 32 Crohn's disease and 29 ulcerative colitis patients, 33 healthy controls, and 27 splenectomized patients. Perendoscopic intestinal biopsies were also collected from 15 of 32 Crohn's disease patients, 14 of 29 ulcerative colitis patients and 13 of 33 control subjects. Counting of erythrocytes with membrane abnormalities (pitted red cells) was used as an indicator of splenic function and flow cytometry was performed to analyze both peripheral and mucosal B cells. RESULTS: Twelve of 32 Crohn's disease patients and 13 of 29 ulcerative colitis patients had pitted red cell values >4% and were considered to be hyposplenic. In inflammatory bowel disease patients circulating IgM memory B cells were significantly lower than in control subjects. We observed a significant inverse correlation between the frequency of circulating IgM memory B cell and the pitted red cell values in inflammatory bowel disease patients with hyposplenism. To exclude the possibility that the reduction of circulating IgM memory B cells reflected their recruitment in the inflamed bowel mucosa, lamina propria B-cell populations were also characterized. We found that the frequency of IgM memory B cells was similar in the blood and in the lamina propria of the same patient. CONCLUSIONS: Our findings show that peripheral IgM memory B cells are reduced in inflammatory bowel disease patients and this defect seems to be related to the impairment of splenic function.  相似文献   
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Morbid obesity is associated with cholesterol gallstone formation, a risk compounded by rapid weight loss. Laparoscopic gastric banding allows for a measured rate of weight loss, but the subsequent risk for developing gallstones is unknown. METHOD: Twenty-six normal-weight volunteers (body mass index [BMI] less than 30) were compared with 14 morbidly obese patients (BMI greater than 40). Gallbladder volumes were measured ultrasonographically, after fasting and following stimulation with intravenous cholecystokinin-octapeptide (CCK-8) RESULTS: Preoperatively, fasting gallbladder volume and residual volume after CCK stimulation were both two times greater in the obese group (P<0.02 versus controls). Per cent gallbladder emptying was not different. Gallbladder refilling was four times higher in the obese patients (P<0.01). By six weeks postoperatively, the obese patients lost 1.4+/-0.1% body weight per week. Gallbladder emptying decreased 18.4% (80.3+/-3.9% to 65.5+/-6.9%; P<0.05); residual volume rose one-third (not significant), and refilling fell 60.5% (0.43+/-0.09 to 0.26+/-0.04 mL/min; P=0.07). Three patients with weight losses of greater than 1.7% per week developed gallstones; gallbladder emptying fell outside the 95 percentile. By six months, weight loss slowed to 0.5+/-0.1% per week; gallbladder motility improved modestly. No further stones developed. CONCLUSION: Rapid weight loss following laparoscopic gastric banding impairs gallbladder emptying and when pronounced, gallstones form by six weeks postoperatively. The accompanying reduction in gallbladder emptying, increased gallbladder residual volume and decreased refilling promote gallbladder stasis and hence stone formation.  相似文献   
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PURPOSE: This study was designed to test the hypothesis that the extent of anal sphincter muscle injury as graded at endosonography correlates with the degree of functional impairment. METHODS: Three hundred and thirty adults presenting for evaluation of fecal incontinence were recruited. Ultrasound was performed with a 7.5-MHz radial rotating axial endoprobe in the left lateral position. Anal sphincter muscle tears were graded on the basis of the degree of circumferential involvement (< or >25 percent) and by an assessment of the superoinferior longitudinal extent of an external anal sphincter tear. Muscles that demonstrated multiple tears, poor visualization, or fragmentation were classed as fragmented. Sphincter injuries were correlated with basal and squeeze pressures at manometry, pudendal nerve terminal latencies, and the severity of symptoms using the Parks-Browning clinical score. RESULTS: Patients with an intact external anal sphincter had a higher squeeze pressure (mean, 162.6 cm H(2)O) than those with a partial- (mean, 125.7 cm H(2)O) or full-length tear (mean, 124.9 cm H(2)O; P < 0.0001). There was no significant difference in squeeze pressure between those with partial- vs. full-length external anal sphincter tears nor between circumference tears < or >25 percent. Basal pressure was significantly lower in those with a full-length external anal sphincter tear (47.8 cm H(2)O) vs. an intact external anal sphincter (65.7 cm H(2)O; P < 0.001). The basal pressure in those with an intact internal anal sphincter was not significantly different from those with clearly defined internal anal sphincter tears, and the degree of circumferential involvement was also not important in this regard. However, those with a fragmented internal anal sphincter had a significantly lower basal pressure than other subgroups of internal anal sphincter injuries (P < 0.001). There was no association between external or internal anal sphincter status and the mean pudendal nerve terminal motor latency, suggesting the patient groups were neurologically similar. There was no significant association between external or internal anal sphincter status and the severity of reported symptoms. CONCLUSION: Correlations between the presence or absence of muscle tears and reduced manometric function have been identified. Further grading of tears was of less importance. No relationship between muscle injuries and the severity of clinical symptoms could be elicited.  相似文献   
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Recurrent neurally mediated syncope represents a common clinical event and a therapeutic challenge. Recently tilt training has been proposed for the treatment of recurrent neurally mediated syncope. To evaluate the efficacy of tilt training in preventing tilt-induced syncope and its feasibility, this controlled, randomized study was undertaken. Sixty-eight consenting patients (25 males and 43 females, mean age 40 +/- 19) with recurrent neurally mediated syncope and 2 consecutive positive nitroglycerin-potentiated head-up tilt tests were randomized to tilt training (35 patients) or no treatment (controls, 33 patients). The tilt training programme consisted of daily 30-min sessions of upright standing against a vertical wall 6 days a week for at least 3 weeks, until a reevaluation tilt test (3 patients of both groups dropped out). On this third head-up tilt test, 19 (59%) of 32 tilt trained patients and 18 (60%) of 30 controls still had a positive test. Treated patients performed a mean number of 15 +/- 7 sessions (median 16) and only 11 patients (34%) did all the programmed sessions. Only 1 patient (3%) discontinued treatment because of intolerance, while all other patients did not perform tilt training adequately, because of poor compliance. Thus, in our study tilt training was not effective in reducing tilt testing positivity rate in patients with neurally mediated syncope. Because of poor compliance, tilt training appears to be a feasible treatment only for highly motivated patients, but not for the majority of patients with recurrent neurally mediated syncope.  相似文献   
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