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81.
82.
Objectives : To determine the efficacy of antimicrobial treatment in non-dysenteric persistent diarrhoea in a community setting. Methods : In this double-blind field trial, 156 children aged 4 36 months with persistent diarrhoea not associated with Giardia lamblia infestation seeking treatment in a community outpatient clinic, were randomized to receive a combination of nalidixic acid and metronidazole, metronidazole alone, or placebo for 7 days. Results : In comparison with placebo, metronidazole treatment did not result in a significant reduction in the mean post-enrolment diarrhoeal duration and stool frequency, increase in the proportion of patients recovered by days 3, 5 and 7 of treatment, and increase in weight gain at days 7 and 14. Comparing the combination of nalidixic acid and metronidazole with metronidazole alone, 17.5% more children treated with the combination recovered by day 3 of treatment ( p = 0.08) and the mean stool frequency ascertained on day 7 for the previous 24 h was 26.8% less in them ( p = 0.05). The weight gains at days 7 and 14 were similar in the two groups. Conclusions : These findings indicate that metronidazole offers no therapeutic benefit in persistent diarrhoea not associated with Giardia lamblia and nalidixic acid has only a modest clinical benefit, which is not substantial enough to warrant its routine use.  相似文献   
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84.

Background

Haemorrhage after Cardio Pulmonary Bypass (CPB) Surgery is a well recognised complication that leads to significant morbidity and mortality. The incidence varies between 5-25% depending upon the clinical situation. Several factors are implicated as causative but none have been precisely proved.

Methods

Our study was an attempt to evaluate the haemostatic defect with particular reference to platelet function abnormalities during cardio pulmonary bypass surgery, in order to reduce the morbidity and mortality associated with post CPB haemorrhage. Flow cytometric evaluation of different platelet glycoproteins like GPIb/IX, GPIIb/IIIa and GMP-140 was done.

Results

The marker expression showed deregulation during surgery which returned to base after bypass was terminated. In contrast, the cases with bleeding showed significant variation. P-Selectin (GMP 140) expression decreased progressively till 3rd post-operative day showing lack of activation of platelets in cases of severe bleeding.

Conclusion

Longer duration of CPB initiates plasmin generation through heparin, which raises the PAI-1-tPA complex and thereby down regulating the functions of platelets. This suggests a link between duration of CPB, bleeding, platelet dysfunction and fibrinolysis. Hence serial estimations of the levels of GMP-140 and tPA can predict severe bleeding.Key Words: CardioPulmonary Bypass, Platelet dysfunction, flowcytometry, platelet glycoproteins, haemorrhage  相似文献   
85.
Background. Impedance cardiography (ICG) has been used extensivelyto estimate stroke volume (SV) and cardiac output (CO) fromchanges of thoracic electrical bioimpedance (TEB). However,studies comparing ICG with reference methods have questionedthe reliability of this approach. Electrical velocimetry (EV)provides a new algorithm to calculate CO from variations inTEB. As the transoesophageal Doppler echocardiographic quantificationof CO (TOE–CO) has emerged as a reliable method, the purposeof this study was to determine the limits of agreement betweenCO estimations using EV (EV–CO) and TOE–CO. Methods. Standard ECG electrodes were used for non-invasiveEV–CO measurements. These were placed on 37 patients scheduledfor coronary artery surgery necessitating transoesophageal echocardiographymonitoring. Simultaneous EV–CO and TOE–CO measurementswere recorded after induction of anaesthesia. EV–CO wascalculated using the Bernstein–Osypka equation. TOE–COwas measured across the aortic valve using continuous-wave Dopplerechocardiography and a triangular orifice model. Results. A significant high correlation was found between theTOE–CO and the EV–CO measurements (r2=0.86). Datawere related linearly. The slope of the line (1.10 (SE 0.07))was not significantly different from unity, and the point atwhich it intersected the ordinate (–0.46 (0.32) litremin–1) was not significantly different from zero. Bland–Altmananalysis revealed a bias of 0.18 litre min–1 with narrowlimits of agreement (–0.99 to 1.36 litre min–1). Conclusions. The agreement between EV–CO and TOE–COis clinically acceptable, and these two techniques can be usedinterchangeably.   相似文献   
86.
AIM: Due to several bad results of studies, titanium is no longer used as an implant material in cemented total hip arthroplasty. This study attempts figure out by means of a meta-analysis if the material titanium itself was responsible for the bad results of some studies or if specific implant characteristics contributed to implant failure, independent of titanium. METHOD: Studies between 1960 and July 2002 were analysed concerning failure rates of cemented titanium total hip arthroplasties regarding their specific implant characteristics. RESULTS: Specific implant characteristics such as roughness of the surface and geometrical features led to significantly different failure rates. Stems of titanium with a dull surface and a wide proximal geometry could achieve such good results as those of the cobalt-chromium stems published in the study results of Malchau. CONCLUSION: Titanium is justified as a cementable material in total hip arthroplasty. By respecting specific implant characteristics, very good failure rates can be achieved. The high failure rates, published in several studies, are based upon implant characteristics which are not suitable for cementing techniques and not upon the implant material titanium itself.  相似文献   
87.
88.
BACKGROUND: Immunosuppressive treatment initiated at an early stage in patients with idiopathic membranous nephropathy (iMN) improves renal survival. Treatment should ideally be restricted to high-risk patients. AIM: To evaluate the efficacy of a restrictive immunosuppressive treatment strategy for patients with iMN. DESIGN: Prospective cohort study evaluating a predefined treatment protocol. METHODS: From 1988, we adopted a restrictive treatment strategy: immunosuppressive treatment, mainly consisting of cyclophosphamide and steroids, was advised only in patients with renal insufficiency or severe intolerable nephrotic syndrome. We evaluated this strategy in a large patient cohort. To exclude any bias, we included all adult patients with iMN biopsied in the study period with a serum creatinine (Scr) < 135 micromol/l, a proteinuria > or = 3.0 g/day and/or a serum albumin (Salb) < or = 30 g/l at the time of biopsy. Analysis was according to the intention-to-treat principle. RESULTS: We studied 69 patients. At the time of biopsy, mean age was 51 years, Scr 90 micromol/l, Salb 23 g/l and proteinuria 6.7 g/day. Average follow-up was 5.5 years. Thus far 33 (48%) patients have received immunosuppressive therapy, mainly because of renal insufficiency (n = 24). Status at the end of follow-up was: complete remission n = 22 (32%), partial remission n = 24 (35%), nephrotic syndrome n = 15 (22%), persistent proteinuria n = 1 (1.4%), ESRD n = 6 (8.7%), death n = 1 (1.4%; due to bladder carcinoma after cyclophosphamide therapy). Patient survival was 100% at 5 and 7 years. Renal survival was 94% at 5 years and 88% at 7 years. DISCUSSION: In patients with iMN, a restrictive treatment policy assures a favourable prognosis, while preventing exposure to immunosuppressive therapy in >50% of the patients.  相似文献   
89.
90.
INTRODUCTION: We present prospective medium-term results of the modular revision prostheses "MRP-TITANIUM". MATERIAL AND METHODS: 45 patients (n = 48 prostheses) were evaluated. The mean follow-up was 4.7 years (min.-max.: 1.0-9.0 years). Pre- and postoperatively the Harris hip score (differentiated to Paprosky I-III) was examined. 66.67 % of the cases had extensive bony defects (> or = Paprosky II b). By means of X-ray examinations, the stability of the prostheses, periprosthetic bone remodelling, the presence of radiolucent lines as well as bone defect regeneration were assessed postoperatively. RESULTS: The mean Harris hip score improved from 25.6 preoperative to 71.4 postoperative (p < or = 0.05). In 44 cases the X-ray showed stable fixation without secondary migration. In one case the stem (stand time 2.36 years) was revised due to secondary migration (> or = 5 mm). The survival rate (Kaplan-Meier) was 97 %. Bone transplantation with consecutive defect regeneration was (n = 30) complete in all cases. In six cases (12.5 %) a postoperative dislocation occurred with subsequent successful closed reposition four times (8.3 %). In two cases (4.2 %) an open reposition was done with correction of the antetorsion angle of the prostheses. CONCLUSION: The "MRP-TITANIUM modular revision prostheses" has proved to be reliable in cases of revision surgery with extensive bony defects. The failure rate was 2.1 % for 48 prospectively examined prostheses.  相似文献   
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