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11.
Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.  相似文献   
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BACKGROUND: Metabolic evaluation in recurrent idiopathic calcium renal stone-formers (RCSF) was analysed with respect to the following questions: (1) do three 24-h urines provide more diagnostic accuracy in the metabolic evaluation of RCSF than 1 or 2 urines?; (2) does time after stone event influence the diagnostic yield?; (3) is urine composition at weekends different from that at mid-week?; (4) what are the prevalences of the most important risk factors (RF) of idiopathic calcium nephrolithiasis, i.e. low volume (LV), hypercalciuria (HC), hyperoxaluria (HO), hyperuricosuria (HU), hypocitraturia (Hypo-Cit), and hypomagnesiuria (Hypo-Mg)?; and (5) do male RCSF differ from females with respect to urinary RFs? METHODS: Seventy-five RCSF (59 men, 16 women) collected three 24-h urines (U1-3) while on free-choice diet. To account for possible variations in lifestyle and diet, U1 and U3 had to be collected midweek and U2 at a weekend. RESULTS: When considering all three urines together (U1 + U2 + U3), the number of RF abnormalities/patient was 2.8 +/- 0.1, higher than numbers of any combination of two urines or of any single urine (P = 0.0001 for all comparisons). The number of RF abnormalities also rose with time after stone event, from 0.8 +/- 0.1 (range 0-4) in U1 to 1.1 +/- 0.1 (range 0- 4) in U3 (P = 0.011 vs U1). Whereas all other RF did not change between collections, urine volume was lower in U2 (1793 +/- 90 ml) than in U1 (2071 +/- 97 ml, P = 0.0001 vs U2) and U3 (1946 +/- 97 ml, P = 0.046 vs U2). At least 1 abnormality was found in 85.3% of all RCSF, and multiple abnormalities occurred in 47%. The most frequent RF was HC (39%), followed by HO and LV (32% each), Hypo-Cit (29%), HU (23%) and Hypo-Mg (19%). Males more often had Hypo-Cit (P < 0.001) and Hypo-Mg (P < 0.01) than females, whereas HO was more frequent in female RCSF (P < 0.025 vs males). CONCLUSIONS: Diagnostic accuracy of metabolic evaluation in RCSF increases both with the number of urines collected and the time passing after a stone event. Urines collected at weekends differ from those of the week only by their lower volumes. Abnormalities of RF for calcium nephrolithiasis can be detected in 85.3% of RCSF, and HC is the most common RF both in male and female RCSF.   相似文献   
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Loss of muscle mass and altered body fat distribution (i.e. increased central fat stores in the presence of normal peripheral fat stores) have been reported in patients on hemodialysis (HD), when compared to normal volunteers. Whether treatment of end-stage renal disease (ESRD) with continuous ambulatory peritoneal dialysis (CAPD) would alter body composition in a different manner than HD is unknown. To answer this question, two groups (n = 11 each) of male patients with ESRD (matched for age, residual renal function, body weight and body height as well as physical activity) were studied. Muscle mass and body fat distribution were assessed using computed tomography. Mid-thigh muscle area, peripheral and central fat stores were similar between the two groups of dialysis patients. In both patient groups muscle mass and fat stores were independent of duration of dialysis, age, daily protein intake and residual renal function. In CAPD-patients mid-thigh muscle area was correlated with plasma albumin (r = 0.56, p < 0.05), while serum cholesterol level was correlated with mediastinal fat area (r = 0.81, p < 0.01). The present results indicate that both treatment modalities of ESRD (HD vs CAPD) result in similar changes of body composition. Despite continuous glucose loading in CAPD-patients, neither central nor peripheral fat stores are increased in these subjects compared with HD treated patients.  相似文献   
14.
One theory of the cause of connective tissue capsule formation around silicone mammary prostheses is based on an immunological interaction. In an in vitro pilot study, it is shown that intraluminal cyclosporine A, a potent T-lymphocyte-specific immunosuppressive agent, can diffuse slowly through the outer shell of a standard double-lumen silicone breast implant. Round silicone tissue expanders containing 50 mg of cyclosporine A were implanted subcutaneously in 10 rats. Ten animals served as controls. Evaluation was performed after three months. A significant decrease in collagen capsular thickness of 21.6 +/- 5.4 microns (mean +/- standard deviation was measured histomorphometrically in the treated group compared with 39.6 +/- 8.6 microns in the control group (p less than 0.001).  相似文献   
15.
During 1986 and 1987, 47 patients with renal cell carcinoma were evaluated preoperatively with CT, angiography and MRI. The preoperative tumor stage (T), lymph node metastases and venous involvement determined with the three methods were compared to the operative and histopathological findings. For T stage, angiography proved less accurate (54%) than CT (64%) or MRI (63%). MRI was found to be superior to CT in assessing lymph nodes, with an overall accuracy of 89% and sensitivity of 100% compared to 77 and 60%, respectively, of CT. For venous involvement CT was overall more accurate (74%) than angiography (65%) or MRI (63%). All three methods expressed a low sensitivity (between 31 and 41%) and a high specificity (between 95 and 100%) for detecting venous involvement. The minimal advantages of MRI compared to its high cost do not justify its routine use. CT remains the method of choice in staging preoperatively renal cell carcinoma.  相似文献   
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Variants of chronic myeloproliferative disorders (CMPD) were compared according to their clinical features and classified by bone marrow biopsy appearances. Subsequently, this classification was further evaluated using survival data and histological variables from iliac crest biopsy specimens of an additional 1391 patients, making a total of 2241 patients available for analysis of outcome. The patients were grouped again into three main classes: "typical"; "variant"; and "transformed". "Typical" comprised the "classic" groups. "Variant" included the less uniform myeloproliferative syndromes, distinguished also by more variable clinical features, a different prognosis, and a greater tendency to fibrotic and blastic transformation. "Transformed" defined the end stages of both "typical" and "variant" types. Ten subgroups were distinguished by different histology and prognosis. Particular prognostic importance was assigned to atypia and immaturity of haemopoiesis, predominance of individual haemopoietic cell line, number and anomalies of megakaryocytes and progressive fibrosis. It is suggested that the proposed subclassification would be helpful for studies of epidemiology and therapeutic trials by allowing more homogeneous groups to be recognised.  相似文献   
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Zusammenfassung Die relative Wirksamkeit von synthetischem Secretin (Wünsch) und reinem natürlichen Secretin ohne Zusatz von Cysteinhydrochlorid (Mutt) sowie von reinem natürlichem Secretin mit Zusatz von Cysteinhydrochlorid (G.I.H. Research Unit) wurde am Parameter der Volumen-und Bicarbonatsekretion des Pankreas bei 10 narkotisierten Bastardhunden geprüft. Die relative Wirksamkeit von synthetischem Secretin liegt — bezogen auf Gewichtsbasis — bei 100% gegenüber natürlichem (Mutt) (Parameter: Volumen- und Bicarbonatsekretion). Die biologische Aktivität von synthetischem Secretin beträgt ungefähr 3,58 klin. E/µg (Parameter: Volumensekretion) bzw. 3,88 klin. E/µg (Parameter: Bicarbonatsekretion) gegenüber dem Secretin mit Zusatz von Cysteinhydrochlorid (G.I.H. Research Unit). Natürliches Secretin (Mutt) hat eine biologische Aktivität gegenüber dem Secretin mit Zusatz von Cysteinhydrochlorid (G.I.H. Research Unit) von annähernd 3,52 klin. E/µg (Parameter: Volumensekretion) bzw. 3,48 klin. E/µg (Parameter: Bicarbonatsekretion).Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
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