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31.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
32.
The capacity of chronically hemodialyzed patients to metabolize acetate during conventional hemodialysis was evaluated using a retrospective study in 219 patients dialyzed for up to ten years under similar dialysis conditions. For each patient, and using all available data, a regression line relating the changes of plasma total CO2 during dialysis as a function of the pre-dialysis value was calculated. The intercept of this function indicates the plasma concentration where the losses of bicarbonate in the dialysate is matched by the generation of bicarbonate arising from the metabolism of acetate. This value therefore represents an individual index of the capacity of each patient to metabolize acetate. A value for this index smaller than 18.0 mM was considered abnormal. It was shown that around 10% of chronically hemodialyzed patients are clearly unable to metabolize acetate optimally. This defect is not related to the duration of dialysis, body weight or quality of hemodialysis treatments but is strongly related to sex, 19 of the 22 "acetate intolerant" patients being women. In a prospective study, all the 60 patients of the same population undergoing active dialysis were studied, and this index identified 12 abnormal (11 women, 1 man) patients and 48 normal patients. Plasma acetate measured at the end their dialysis treatments were significantly higher in abnormal than in normal patients. It is concluded: that this index is useful to identify the patients unable to metabolize acetate optimally; that only around 10% of hemodialyzed patients present a severe problem when dialyzed against acetate and should be dialyzed against bicarbonate; that dialysis against acetate does not fully correct the metabolic acidosis even in "normal" patients.  相似文献   
33.
Advances in techniques of molecular biology have made possible the amplification of specific genes from single cells. This has a major clinical application in preimplantation diagnosis of monogenic disorders. However, the incidence of allele specific amplification failure (allele drop out) in heterozygous single cells can lead to misdiagnosis and the transfer of affected embryos. Few studies have been done to investigate the actual cause of allele drop out, although some investigators have succeeded in reducing but not eliminating it. Here we report the efficiency of amplifying both alleles in heterozygous cells lysed according to two different protocols. A total of 177 heterozygous cells from carriers of cystic fibrosis (CF) and haemoglobin C (HbC) were lysed using two different lysis buffers. Interestingly none of the cells that were lysed with sodium dodecyl sulphate/proteinase K showed any example of allele specific amplification failure whereas in those lysed by KOH/dithiothreitol it was present in 17.6 and 4.7% of the CF and HbC cells respectively. Our results suggest that the phenomenon of allele specific amplification failure is at least in part dependent on the lysis buffer used.   相似文献   
34.
Even 10 yr after the identification of the antiphospholipid syndrome (APS), renal involvement in the course of APS is still relatively unrecognized, and is probably underestimated. The association of anticardiolipin antibodies and/or lupus anticoagulant with the development of a vaso-occlusive process involving numerous organs is now confirmed. In a multicenter study, 16 cases of "primary" APS (PAPS) were found and followed for 5 yr or more, all with renal biopsy. In all 16 cases of PAPS, there was a vascular nephropathy characterized by small vessel vaso-occlusive lesions associated with fibrous intimal hyperplasia of interlobular arteries (12 patients), recanalizing thrombi in arteries and arterioles (six patients), and focal cortical atrophy (10 patients). In combination, these led to progressive destruction of the kidney, accelerated by acute glomerular and arteriolar microangiopathy in five patients. Focal cortical atrophy is a distinctive lesion, present in 10 biopsies, and likely represents the histologic and functional renal analogue to the multiple cerebral infarcts detected on imaging studies. The clinical hallmark of this vascular nephropathy in PAPS is systemic hypertension, only variably associated with renal insufficiency, proteinuria, or hematuria. The ensemble of histologic renal lesions defined in this study should aid in the separation of the lesions found in cases of secondary APS, especially systemic lupus erythematosus, into those lesions related to APS and those related to the underlying disease.  相似文献   
35.
In a simulated field trial Bacillus thuringiensis var israelensis (BTI) pellet formulation exhibited an enhanced efficacy with increasing dose. A dosage of 1.0 and 1.5 ppm was most effective under simulated field conditions. In field trials persistence of BTI pellet (1.0 ppm) was observed for 35 days in moderately polluted water collection as compared to 21 days in highly polluted water bodies.KEY WORDS: Bacillus thuringiensis, Malaria, Mosquito control  相似文献   
36.
Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections.

Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan‐Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates.

Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow‐up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T‐lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance.

Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T‐lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.  相似文献   

37.
The authors investigate the importance of physical symptoms as a correlate of depressive symptoms and suicidal thoughts in a large (N = 881) community-based sample of persons infected with human immunodeficiency virus. The study overcomes limitations of prior research by minimizing overlap in measures of affective and physical symptoms, studying a more diverse population, and including correlates such as measures of social support, function, employment, insurance coverage, and cognitive impairment in the analysis. The authors' data support the notion that in diagnosing depression in the medically ill, concern over isolating physical symptoms as either "affective" or "physical" may be exaggerated.  相似文献   
38.
In this paper we present two cases in which thyroid disorders were unexpectedly brought to view. The question we ponder is whether hidden thyroid dysfunction may be important in the cause, mechanism and manner of death, or just an incidental discovery during the post-mortem examination. A short literature review has been conducted in order to evaluate previously reported cases of thyroid pathology and sudden death. The significance of post-mortem evaluation of thyroid hormones (T3 and T4) will be considered briefly.  相似文献   
39.
EXACERBATIONS DURING PREGNANCY: Clinical and experimental data have clearly evidenced the influence of hormones on the course of systemic lupus erythematosus. In prospective studies of pregnant women, an exacerbation is observed in 57% to 60% of the cases. It can be severe in 10% of the cases and occur in the post partum in 7%. For most patients, the exacerbation is moderate and has no unfavorable effect on the outcome of pregnancy. In case of renal involvement, it is difficult to differentiate an intricated HELPP syndrome. MARKERS AND RISK FACTORS: Low complement and elevated anti-DNA levels are distinctive markers. Earlier renal involvement and hypertension are important prognostic factors, particularly when the lupus begins during pregnancy. However, when serum creatinine is lower than 100 mumol/l at pregnancy onset in patients in remission, pregnancy does not alter renal function. An association with antiphospholipid antibodies increases the risk for the fetus and the kidney function. TREATMENT: Optimal treatment remains to be defined. Commonly, patients are given aspirin, heparin in case of a history of thromboembolism, or both. The rate of success currently exceeds 70%. The risk of thromboembolism in the peri or post partum period requires anticoagulant treatment. Outside pregnancy: Ovulation induction raises two risks: triggering a lupus flare-up and thrombosis, particularly for patients with antiphospholipid antibodies. The influence of menopause and hormone replacement therapy remains poorly understood.  相似文献   
40.
A FREQUENT OCCURRENCE: Dermatological manifestations are frequently observed in patients with relapsing polychondritis. However, they have not been extensively studied as polychondritis is a rare disease and the reported dermatological manifestations appear to be nonspecific. A WIDE SPECTRUM: The most frequently observed manifestations are aphthosis with sometimes complex aphthosis, nodular papular or purpuric lesions. Neutrophilic dermatosis has been reported in isolated cases. Histologically, these lesions correspond to nonspecific inflammatory infiltrates, vasculitis or thrombosis. Various pathological findings are observed in nodular lesions. RELATED AND OVERLAP CONDITIONS: Similar dermatological manifestations occur in Beh?et's syndrome and in inflammatory bowel diseases. Patients with relapsing polychondritis and myelodysplasia very frequently have dermatological manifestations. Repeated blood cell determinations are therefore necessary in patients with relapsing polychondritis and dermatological manifestations.  相似文献   
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