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31.
Orthotopic liver transplantation was performed in 20 pigs. Serum total bile acids (STBA) were determined and their profile compared with standard early function parameters: total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactic acid. In phase I, the STBA level was 32.89 +/- 1.29 mumol/l. In phase II, STBA accumulated to 84.46 +/- 15.25 mumol/l (p less than 0.01), followed by hepatic clearance in phase III (63.61 +/- 9.71 mumol/1; NS). Between phase III and 6- and 12-hour samples, STBA decreased progressively, reaching values of 33.63 +/- 7.05 mumol/l at 24 h. AST was elevated in phases I, II, III, and at 6, 12 and 24 h (p less than 0.001), as was ALT (but with insignificant differences). Thus, STBA and their profile appear to be earlier and more specific indicators of early graft function than conventional parameters.  相似文献   
32.
BACKGROUND: In 1998, the UK government issued precautionary advice that pregnant or breast-feeding women with a family history of atopy, may wish to avoid eating peanuts during pregnancy and lactation. This study aimed to assess the compliance with this recommendation and investigate its impact upon peanut sensitization. METHODS: A total of 858 children born immediately after the advice were followed for 2 years and assessed for peanut sensitization. A standardized questionnaire was used to ascertain history of atopy and maternal exposure to peanuts during pregnancy. Following parental consent children were skin prick tested to assess sensitization to peanuts. RESULTS: Sixty-five per cent of mothers had avoided peanuts during pregnancy. Forty-two per cent of the mothers had heard about the government advice, and half modified their diet as a consequence. Neither maternal nor family history of atopy had any significant effect on peanut consumption. Parity did play a role, and mothers having their first child were twice as likely to change their diet (P<0.001). Mothers of 77% of the children sensitized to peanuts had avoided peanuts during pregnancy. In this cohort study maternal consumption of peanut during pregnancy was not associated with peanut sensitization in the infant. CONCLUSIONS: The majority of mothers in this cohort avoided peanut consumption during pregnancy. It is likely that either the government advice is misunderstood by mothers, or that those who communicate the advice have not fully explained who it is targeted at.  相似文献   
33.
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months  相似文献   
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35.
OBJECTIVES: Assessment of morphological characteristics of lymphnodes studied ex-corpore by echoendoscopy--shape, sharpness of limits, echogenicity and dimensions--to categorize them either as metastatic or non-metastatic. MATERIAL AND METHODS: Fifty-four lymphnodes were studied. They were identified and studied by echoendoscopy in fresh surgical specimens of oesophagus, stomach and rectum. Eight nodal characteristics were evaluated. The data obtained were studied by multivariate analysis using the logistical estimate method in two different statistical models. RESULTS: In model 1, logistical estimate demonstrated that well-defined limits (WDL) of the lymphnodes and the association of hypoechogenicity and round shape were the most significant variables suggesting the presence of invasion. In model 2, the most significant variables were WDL, round shape and association of round shape with WDL. The first model had a high sensitivity of 93.1% and specificity of 68% whereas the second model had a greater specificity of 84%, with a slight fall in sensitivity. CONCLUSION: These models might have an application to clinical practice particularly in the pre-operative assessment of patients with oesophageal carcinoma, gastric carcinoma or rectal carcinoma.  相似文献   
36.
BACKGROUND: Aerobic exercise training has been associated with beneficial effects on the cardiovascular system, improving arterial compliance, possibly related to a positive impact on the endothelium. The effects of competitive aerobic exercise are not so well documented. This prompted us to evaluate the possible modulation of arterial properties in a group of athletes and their response to the aging process. METHODS: 423 healthy males were enrolled in a cross-sectional study, 212 of whom were competitive athletes and 211 were controls. All underwent carotid-femoral pulse wave velocity (PWV) evaluation, and casual blood pressure and other relevant anthropometric data were evaluated. RESULTS: To control the effects of age, each group was divided into two subgroups with an age cut-point of 20 years. PWV was 6.3 +/- 0.9 m/s (athletes) vs. 7.0 +/- 1.0 m/s (controls) for ages <20 years, and 7.6 +/- 1.2 m/s (athletes) vs. 8.1 +/- 0.9 m/s (controls) for ages >20 years, with statistically significant differences in both comparisons. A linear regression model with logarithmic tendency analysis with age as the independent determinant of PWV revealed a different progression of age-related deterioration of aortic compliance between the two groups (athletes and controls). CONCLUSIONS: Our data documented better compliance indices in competition athletes compared with controls, which may reflect optimization of endothelial function. This improvement was age-dependent, being less pronounced as the athletes grow older, which could be due partially to sustained stretching effects on the arterial walls in long-term competitors.  相似文献   
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38.
All 253 children receiving neurosurgical intervention for hydrocephalus (HCP) at a single British Neurosurgical Unit over a decade were investigated by retrospective case note review. Referral rates and mean age at presentation remained stable throughout, as did proportions of children presenting due to myelomeningocoele or meningitis. Comparing the first and second halves of the decade, the predominant aetiologies (intraventricular haemorrhage [IVH] at <1 year and brain tumour at 1-16 years) reduced from comprising half (70/129) of all cases to just over one-third (43/124). Other significant changes included a 45% reduction in neonatal IVH and a 179% increase in rare miscellaneous disorders. Outcome after 4 years of follow-up for all patients showed 44.4% without deficit, 11.9% with non-cognitive neurological deficits only, 11.5% with cognitive impairment only, 13.5% with both cognitive and neurological impairments, and 15.5% mortality.  相似文献   
39.
Atraumetic Restorative Treatment (ART) has been adopted around the world to avoid unnecessary extractions, especially in non-industrialized countries The development of specific glass ionomer cements marketed for the ART technique has contributed to the technical success rate. In this study. Ketac-Molara (3M ESPE. Dental Medzn Germany) was used to restore 150 Class I cavities in 118 Brazilian public school children, aged from 7–12 years. At baseline and at subsequent recalls. CPI probes with a ball-end of 0.5 millimeters (mm) were used to assess loss of restorative material, and photographic color transparencies of restorations were made. After six months. 83 patients returned for follow-up examinations, with 71.8% of their restorations designated as acceptable. After three years. 49 patients with 57 ART-restorations were evaluated, with 21.0% of these restorations graded as acceptable Another 29.8% of their restorations had been replaced by more permanent materials. The main objective of the ART technique is tooth retention; this was achieved for 94.7% of the restored teeth in a high caries risk population who returned for recalls.  相似文献   
40.
The ability of the Lyme disease spirochete to attach to host components may contribute to its ability to infect diverse tissues. We present evidence that the Lyme disease spirochete expresses a lectin activity that promotes agglutination of erythrocytes and bacterial attachment to glycosaminoglycans. Among a diverse collection of 21 strains of Lyme disease spirochete, hemagglutinating activity was easily detected in all but 3 strains, and these three strains were noninfectious. The ability to agglutinate erythrocytes was associated with the ability of the spirochete to bind to the sulfated polysaccharide dextran sulfate and to mammalian cells. Soluble dextran sulfate was a potent inhibitor of both hemagglutination and attachment to mammalian cells, while dextran had no effect on either activity, suggesting that dextran sulfate may inhibit attachment by mimicking host cell glycosaminoglycans. Consistent with this, the spirochete bound to immobilized heparin, and soluble heparin inhibited bacterial adhesion to mammalian cells. The bacterium did not bind efficiently to Vero cells treated with heparinase or heparitinase or to mutant CHO cell lines that are deficient in proteoglycan synthesis. Sulfation of glycosaminoglycans was critical for efficient bacterial recognition, as Vero cells treated with an inhibitor of sulfation, or a mutant CHO cell line that produces undersulfated heparan sulfate, did not mediate maximal spirochetal binding. Binding of the spirochete to extracellular matrix also appeared to be dependent upon this attachment pathway. These findings suggest that a glycosaminoglycan-binding activity which can be detected by hemagglutination contributes to the attachment of the Lyme disease spirochete to host cells and matrix.  相似文献   
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