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1.
Our purposes were to determine the incidence of BK viruria, viremia or nephropathy with tacrolimus (FK506) versus cyclosporine (CyA) and whether intensive monitoring and discontinuation of mycophenolate (MMF) or azathioprine (AZA), upon detection of BK viremia, could prevent BK nephropathy. We randomized 200 adult renal transplant recipients to FK506 (n = 134) or CyA (n = 66). Urine and blood were collected weekly for 16 weeks and at months 5, 6, 9 and 12 and analyzed for BK by polymerase chain reaction (PCR). By 1 year, 70 patients (35%) developed viruria and 23 (11.5%) viremia; neither were affected independently by FK506, CyA, MMF or AZA. Viruria was highest with FK506-MMF (46%) and lowest with CyA-MMF (13%), p = 0.005. Viruria >/= 9.5 log(10) copies/mL was associated with a 3-fold increased risk of viremia and a 13-fold increased risk of sustained viremia. After reduction of immunosuppression, viremia resolved in 95%, without increased acute rejection, allograft dysfunction or graft loss. No BK nephropathy was observed. Choice of calcineurin inhibitor or adjuvant immunosuppression, independently, did not affect BK viruria or viremia. Viruria was highest with FK506-MMF and lowest with CyA-MMF. Monitoring and preemptive withdrawal of immunosuppression were associated with resolution of viremia and absence of BK nephropathy without acute rejection or graft loss.  相似文献   
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Background Insular thyroid carcinoma was described as a tumor with aggressive behavior, and patients usually present themselves with an advanced tumor stage. Whether the insular component is an independent factor for poor prognosis remains unclear. Therefore, in the present study, we compared the survival of patients with advanced insular, follicular, and papillary thyroid cancer. Materials and methods The clinical behavior of tumors in three groups of patients with T4 thyroid carcinoma—8 patients with insular, 11 patients with follicular, and 21 patients with papillary thyroid carcinomas—was compared. Disease-free survival and disease-specific death were analyzed statistically. Cox regression analysis was used to evaluate the influence of histotype and other prognostic factors. Results At 3 years, survival was 37.5% (mean 26 months) among patients with insular thyroid carcinoma, 80% (mean 59 months) among those with follicular, and 89% (mean 126 months) among those with papillary thyroid carcinomas (p = 0.007). Disease-free survival in patients without initial distant metastasis was worst in patients with insular thyroid carcinoma (20%) compared to those with follicular (75%) and those with papillary thyroid carcinomas (71%). Conclusion Patients with advanced insular thyroid carcinoma have a poorer outcome in comparison to patients with similar advanced stage who have follicular or papillary thyroid carcinoma.  相似文献   
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During a phase III open study of depot leuprolide for stage D2 cancer of the prostate, we studied the effect of depot leuprolide on chronic leuprolide users. To determine whether there was a transient elevation of testosterone or luteinizing hormone (LH) 4-24 h and 3-5 days following the monthly injections, we monitored the changes of testosterone and LH before injection and 24 h post-injection in 10 patients who have been under depot leuprolide Rx for 24-36 weeks, and in 35 patients before injection and 3-5 days post-injection who have received depot leuprolide for 8-24 weeks prior to monitoring. Comparison of the data between pre-injection within 24 h and 3-5 days post-injection showed no significant changes of testosterone and LH values between these levels for either testosterone (P = 0.31) or LH (P = 0.45). We therefore conclude that there was no 'acute on chronic' effect of depot formulation in chronic users of depot leuprolide.  相似文献   
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Conventional tube cell culture has been recognised as the most sensitive technique available for human cytomegalovirus (HCMV) detection. Low-speed centrifugation of specimen inocula onto cell culture monolayers has been shown to increase the efficiency of infection with the AD 169 strain of HCMV. Therefore a centrifugal force of 900g for 1 hour at 37 degrees C was used to enhance the detection of HCMV cytopathic effect (CPE) in shell vials that contained circular coverslips with a monolayer of human embryonic lung (HEL) fibroblasts. Of 195 specimens, HCMV CPE was detected in 18 specimens (9.02%) on shell vial culture assay, whereas conventional tube cell culture was positive in only 13 specimens (6.6%). The shell vial culture assay was significantly more sensitive (P less than 0.05). Furthermore the development of the cytopathic effect on shell vial culture assay was significantly earlier (P less than 0.01) and more extensive. Urine samples were sonicated and the results obtained with immunofluorescence using human immune serum demonstrated that sonication increased both the intensity of fluorescence and number of fluorescent foci of HCMV-infected cells and also decreased the non-specific fluorescence of the background.  相似文献   
6.
The expression of major histocompatibility (MHC) antigens on guinea pig T cells was used as a functional marker for lymphocyte activation. Antigen-stimulated lymphocytes were recovered from guinea pigs responding to the contact sensitizer DNFB, and isolated T cells were then phenotyped using a new antiguinea pig monoclonal antibody, MSgp7. The level of expression of MHC class II, as defined by the monclonal antibody, MSgp8, was increased on T cells recovered 4 days after sensitization, as compared with unsensitized controls. The value of this experiment was extended by measuring MHC class II expression on T cells stimulated in vitro by the mitogen concanavalin A, where a clear increase in MSgp8 binding was also observed. Confirmation of the specificity of MSgp8 for guinea pig MHC class II antigens was achieved by studying the inhibitory capacity of this antibody on an MHC class II restricted mixed leucocyte reaction. The combination of antibodies MSgp7 and MSgp8 with flow cytometry could be applied to other guinea pig experimental models to quantitate the expression of MHC class II antigens on T cells to determine their putative value in disease manifestation.  相似文献   
7.
This report reviews the clinical and radiographic features of 40 patients who underwent visceral esophageal substitution with colon for benign or malignant lesions of the esophagus. The incidence and radiographic identification of complications are discussed. All patients were routinely examined with barium esophagrams on postoperative day 10. If an anastomotic leak was suspected clinically before this time, studies were performed using water-soluble iodinated contrast material. Follow-up barium esophagrams were obtained 1-96 months after operation (average, 60 months) in 24 patients. Eight patients (21%) demonstrated asymptomatic "jejunization" of the colonic mucosa with no attributable clinical manifestations; this finding resolved in 1-3 months, without sequelae, and has not been reported before. The spectrum of ischemic changes in the colonic segment included mucosal edema, spasm, ulceration, loss of haustration, and frank necrosis. Radiographically detectable early postoperative complications included anastomotic leak in six (three pharyngocolic, three cervical esophagocolic) and aspiration of barium into the tracheobronchial tree due to incoordinated swallowing in eight. Late postoperative complications included anastomotic narrowing (12) malfunctioning of the colon due to impaired emptying (five), recurrent aspiration pneumonia (three), small bowel obstruction (three), transhiatal herniation of small bowel through the diaphragmatic hiatus (one), and reflux into the retained bypassed esophagus (one).  相似文献   
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BACKGROUND: Previous studies in Pakistan have shown that ghee (clarified butter) is commonly applied to umbilical wounds of neonates, and have documented that such applications are a risk factor for neonatal tetanus (NNT). In-use contamination of ghee with Clostridium tetani has been demonstrated, but mechanisms underlying the risk of ghee have been incompletely evaluated epidemiologically. METHODS: Detailed information on ghee usage, including fuels used to heat it, was obtained from cases of NNT (n = 229) and their matched controls (n = 687) from a population-based study of NNT in Punjab Province, Pakistan. Design variables were created to evaluate the impact of different fuel sources on risk of ghee applications. RESULTS: Nearly one-third of all infants had ghee applied, and it was nearly always heated before application to umbilical wounds of newborns. After controlling for all factors found to be significantly associated with NNT in conditional logistic regression, only ghee that had always been heated with dried cow dung fuel was significantly associated with NNT. Topical antimicrobials and ghee were never applied together. CONCLUSIONS: Ghee applications to umbilical wounds, when heated with 'clean' fuels, appear to pose no increased risk of NNT, although handling practices undoubtedly result in hazardous microbial contamination. In contrast, ghee heated with dung fuel was significantly associated with NNT. The effective promotion of topical antimicrobials might help reduce ghee use, since the intended purpose of each is to enhance healing.  相似文献   
10.
Late presenting complete heart block after pediatric cardiac surgery is a rare complication and its management is well defined once the initial diagnosis in made timely and appropriately. In this report we described a child who underwent atrioventricular septal defect repair with a normal sinus rhythm during the postoperative period, as well as during the first 2 years of follow up.She subsequently developed complete heart block with bradycardia that required insertion of a pacemaker. Here we discuss this unusual late-presenting complication, possible risk factors, and management.  相似文献   
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