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941.
AIMS: To assess the relationship between neighbourhood deprivation and the rate of gestational diabetes mellitus (GDM) using routinely collected data from a clinical information system, in Plymouth, UK. METHODS: Between 1 January 1996 and 31 December 1997, 3933 women residing within the Plymouth Primary Care Trust (PCT) were screened for GDM using indices of neighbourhood deprivation and prevalence of GDM. Areas (n = 43) were classified according to the Townsend index, measuring material deprivation. Pregnant women with and without GDM were compared. RESULTS: The prevalence of GDM was 1.7%[95%, confidence interval (CI) 1.20, 2.11]. The prevalence of GDM ranged from 1.05% (95% CI 0.60, 1.70) in the most deprived to 2.10% (95%, CI 1.34, 3.13), in the least deprived neighbourhood. Crude rates decreased by 50%[relative prevalence (RP) (95% CI) 0.50 (0.27, 0.94); P = 0.06] amongst those living in the most-deprived compared with those living in the least-deprived areas. Using a stepwise binary logistic regression model, older age at delivery significantly increased the risk of developing GDM. [RP (95%, CI) 1.09, (1.04, 1.13)]. Townsend deprivation score had no significant independent association with GDM when other covariates were considered. CONCLUSION: These data suggest that the neighbourhood context in which women live has no impact on the risk of GDM. Diabet.  相似文献   
942.
OBJECTIVE: To assess the frequency of risk factors for rhabdomyolysis with simvastatin and atorvastatin in cases reported to the Australian Adverse Drug Reactions Advisory Committee (ADRAC). DESIGN: Reports meeting the definition of rhabdomyolysis were reviewed for risk factors including age > or = 70 years, dose > or = 40 mg, hepatic dysfunction, diabetes mellitus, hyperkalaemia, hypothyroidism and the use of concomitant interacting medications. RESULTS: Only one report associated with simvastatin and five reports associated with atorvastatin did not list any risk factors for rhabdomyolysis. Interacting medicines featured in 77% of reports of rhabdomyolysis associated with simvastatin and 44% of reports associated with atorvastatin. A comparison of the age profile for reports of atorvastatin- and simvastatin-associated rhabdomyolysis with that for all adverse drug reaction reports received, and for all reports of muscle disorders, suggested a trend towards an increasing risk of rhabdomyolysis with increasing age with simvastatin but not with atorvastatin. Similarly, comparing prescribed tablet strengths from Pharmaceutical Benefits Scheme data with the HMG-CoA reductase inhibitor ('statin') doses in reports of rhabdomyolysis suggested a dose-related risk with simvastatin, but a less increased risk with high-dose atorvastatin. CONCLUSION: Risk factors for rhabdomyolysis featured in nearly all of the reports of statin-associated rhabdomyolysis and the majority of reports listed multiple risk factors, although dependence on risk factors appeared to be stronger with simvastatin than atorvastatin. The multiplication of risk factors in patients taking simvastatin and atorvastatin should be minimised.  相似文献   
943.
PURPOSE: To evaluate the role of adjuvant interferon alfa after complete resection of locally extensive renal cell carcinoma. PATIENTS AND METHODS: A total of 283 eligible patients with pT3-4a and/or node-positive disease were randomly assigned after radical nephrectomy and lymphadenectomy to observation or to interferon alfa-NL (Wellferon, Burroughs-Wellcome, Research Park, NC) given daily for 5 days every 3 weeks for up to 12 cycles. Patients were stratified on the basis of pathologic stage. Patients remained on treatment until documented recurrence, excessive toxicity, or patient/physician preference deemed removal appropriate. RESULTS: At median follow-up of 10.4 years, median survival was 7.4 years in the observation arm and 5.1 year in the treatment arm (log-rank P =.09). Median recurrence-free survival was 3.0 years in the observation arm and 2.2 years in the interferon arm (P =.33). Performance status (P =.003), nodal status (N2 v N0, P <.0001), and tumor stage (P =.0002) were significant prognostic factors in multivariate analysis. A proportional hazards model examining the effects of treatment arm and time to recurrence on survival after recurrence among patients who recurred found that random assignment to interferon treatment (P =.009) and shorter time to recurrence (P <.0001) were independent predictors of shorter survival after recurrence. Although no lethal toxicities were observed, severe (grade 4) toxicities including neutropenia, myalgia, fatigue, depression, and other neurologic toxicities occurred in 11.4% of those randomly assigned to interferon treatment. CONCLUSION: Adjuvant treatment with interferon did not contribute to survival or relapse-free survival in this group of patients.  相似文献   
944.
945.
946.
For several genetic diseases two biological phenomena have been recognised as important: germline mosaicism; and different new mutation rates in males and females depending on mutation type. Both principles have been investigated separately and their influence on risk estimation in families has been exemplified in the literature. The aim of this paper is to present a general model that includes mosaicism and different new mutation rates. Mosaicism is introduced by defining additional alleles at the disease locus in combination with adapted segregation rules. Taking Duchenne muscular dystrophy as an example, we derive the conditions which have to be fulfilled for a population in mutation selection equilibrium. Our approach describes the model at the population level and not in individual subjects. This has the advantage of being able to use well known algorithms for the calculation of likelihoods in pedigrees, and to include additional diagnostic information such as marker genotypes and carrier deletion test results. We demonstrate the impact of the new model on a typical pedigree. In families where the patient is not available, the distinction between point mutations and deletions is important, since often molecular diagnostic tests for females can only screen for deletions. Negative deletion test results can now be included in the risk calculations.  相似文献   
947.
AIM: The present meta-analysis aims to compare short-term and long-term outcomes in patients undergoing laparoscopic or open subtotal colectomy for benign and malignant disease. METHODS: A literature search of Medline, Ovid, Embase and Cochrane databases was performed to identify studies published between 1992 and 2005, comparing laparoscopic (LSC) and open (OSC) subtotal colectomy. A random effect meta-analytical technique was used and sensitivity analysis performed on studies published since the beginning of 2000, higher quality papers, those reporting on more than 40 patients, and those studies reporting on adult cases or acute colitis. RESULTS: A total of eight studies satisfied the criteria for inclusion. These included outcomes on 336 patients, 143 (42.6%) of whom had undergone laparoscopic resection, with an overall conversion rate to open surgery of 5% (range 0-11.8%). Operative time was significantly longer in the laparoscopic group by 86.2 min (P < 0.001) and throughout subgroup analysis, although it was only in patients with acute colitis that this finding was without significant heterogeneity. Operative blood loss was less in the laparoscopic group by 57.5 millilitres in high quality and studies published since 2000, and 65.3 millilitres in those reporting on more than 40 patients. There was no significant difference in early or long-term complications between the groups. A statistically significant reduction in length of postoperative stay was observed in the laparoscopic groups by 2.9 days (P < 0.001). CONCLUSION: Laparoscopic subtotal colectomy was associated with longer operating times but a reduced length of stay compared to open surgery. Although short-term outcomes were equivalent in both groups, the suggested benefits in terms of reduced long-term obstructive complications were not supported by this meta-analysis.  相似文献   
948.
Three-dimensional (3D) PET acquisition has the potential to reduce image noise but the advantage of 3D PET for studies outside the brain has not been well established. To compare the performance of 2-dimensional (2D) and 3D acquisition for whole-body (18)F-FDG applications, a series of patient studies were performed using a lutetium oxyorthosilicate (LSO)-based tomograph. METHODS: Comparative 2D and 3D images were acquired for 27 oncology patients using an LSO-based tomograph. Data acquisition (350-650 keV, 6 ns) started 99 +/- 12 min (mean +/- SD) after injection of 624 +/- 76 MBq (18)F-FDG. Bias caused by tracer redistribution and decay was eliminated by acquiring dynamic data over a single-bed position using a protocol that alternated between septa-in and septa-out modes (2D, 3D, 2D, 3D, 2D, 3D). Frames were combined to form 8 statistically independent sinograms: four 2D replicates (105 s) and four 3D replicates (90 s). The different frame durations in 2D and 3D compensated for the different number of overlapping bed positions required for an 85-cm whole-body study. Images were reconstructed with either 2D or fully 3D ordered-subsets expectation maximization (2 iterations and 8 subsets; 2D 6-mm gaussian, 3D 5- and 6-mm gaussian). Image target-to-background ratio was assessed by dividing the lesion maximum by the mean within a neighboring background region. Image noise was assessed by applying background regions of interest to the replicate images and calculating the within-patient coefficient of variation. RESULTS: The difference in target-to-background ratio between the 2D and 3D images, when they were filtered with 6-mm and 5-mm gaussian filters, respectively, was not highly statistically significant (P = 0.16). The mean ratio of 3D to 2D image values was 0.94 with 95% limits of agreement of 0.63-1.41. The within-patient coefficients of variation for the 2D and 3D images were 13% +/- 15% and 9% +/- 10%, respectively (P = 0.0005). CONCLUSION: Under conditions of matched target to-to-background ratios, the 3D mode was found to produce images with significantly less variability than the 2D mode. These data provide support for the use of 3D acquisition with LSO detectors to reduce scan times in whole-body (18)F-FDG applications.  相似文献   
949.
950.
The term synovial sarcoma was first proposed for the histologically well defined entity by Knox in 1936. The name was proposed due to the fact that at least the cases reported in the early part showed some resemblance of the tumour to normal synovial tissue histologically. Thereafter, tumours have been diagnosed from areas without synovial tissue. The diagnosis of monophasic tumours can be difficult and immunostains appear to be a good diagnostic tool in those cases. The occurrence in the mandible is extremely rare. This is a case of synovial sarcoma arising in the condyle involving most of the ramus. The tumour was diagnosed as synovial sarcoma with predominant spindle cell component by correlation of histopathology with immunostains (cytokeratin, epithelial membrane antigen, actin and desmin). The patient has been treated with surgery and radiotherapy.  相似文献   
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