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1.
The incidence of asthma has been reported to be associated with obesity. An alternative analysis, of net change in prevalence, does not require exclusion of those with asthma at baseline. Follow-up data were obtained from 9,552 participants in the European Community Respiratory Health Survey and the Swiss cohort Study on Air Pollution and Lung Disease in Adults. Incidence of asthma was analysed by proportional hazards regression, and net changes in symptoms and asthma status by generalised estimating equations, by obesity group. Incidence and net change in ever having had asthma were greater in females than in males, and in participants who remained obese compared with those who were never obese (hazard ratio 2.00, 95% confidence interval 1.25-3.20; excess net change 2.8%, 0.4-5.3% per 10 yrs). The effect of being obese on net change in diagnosed asthma was greater in females than in males, but for net change in wheeze without a cold it was greater in males. The present results are consistent with asthma being more frequently diagnosed in females, especially obese females. These findings may help to explain the reports of a stronger association between asthma and obesity in females than in males.  相似文献   
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Ambient light affects pulse oximeters   总被引:1,自引:0,他引:1  
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Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by 9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n = 14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year, by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS) by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS) and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively (25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the first year. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
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OBJECTIVE: The aim of this study was to assess the quality of life and psychologic profile during radiation therapy for head and neck cancer. STUDY DESIGN AND SETTING: The University of Washington QoL instrument and the Hospital Anxiety and Depression Scale were administered to 202 patients at two or three time points during radiation therapy. RESULTS: A total of 118 (54.6%) patients completed the questionnaires at the beginning and at the end of the study. A mid-treatment dataset was also available for 67 (31.0%) patients. There was a statistically significant deterioration in composite QoL scores (P < 0.000) and a statistically significant increase in depression (P < 0.000). There was no difference in anxiety levels (P = 0.276). CONCLUSION: Patients undergoing radiation are increasingly depressed as treatment progresses, with worsening QoL during the treatment. SIGNIFICANCE: This study underlines the need for good psychologic support during radiation therapy in head and neck cancer.  相似文献   
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Posterior polymorphous corneal dystrophy (PPCD) is an autosomal dominant disorder characterized by corneal endothelial abnormalities, which can lead to blindness due to loss of corneal transparency and sometimes glaucoma. We mapped a new locus responsible for PPCD in a family in which we excluded the previously reported PPCD locus on 20q11, and the region containing COL8A2 on chromosome 1. Results of a 317-marker genome scan provided significant evidence of linkage of PPCD to markers on chromosome 10, with single-point LOD scores of 2.63, 1.63, and 3.19 for markers D10S208 (at (circumflex)theta = 0.03), D10S1780 (at (circumflex)theta = 0.00), and D10S578 (at (circumflex)theta = 0.06). A maximum multi-point LOD score of 4.35 was found at marker D10S1780. Affected family members shared a haplotype in an 8.55 cM critical interval that was bounded by markers D10S213 and D10S578. Our finding of another PPCD locus, PPCD3, on chromosome 10 indicates that PPCD is genetically heterogeneous. Guttae, a common corneal finding sometimes observed along with PPCD, were found among both affected and unaffected members of the proband's sib ship, but were absent in the younger generations of the family. Evaluation of phenotypic differences between family members sharing the same affected haplotype raises questions about whether differences in disease severity, including differences in response to surgical interventions, could be due to genetic background or other factors independent of the PPCD3 locus.  相似文献   
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Fifty-one cases of central, hyalin cartilage tumors of the long and flat bones were analyzed. Although Grade 2 and 3 chondrosarcomas could be diagnosed on the basis of cytologic features alone, low-grade chondrosarcoma could not be adequately differentiated from pure, benign enchondroma(s) by cytology alone. The tumors can be distinguished by a new histologic approach based on tissue patterns. The crucial enchondroma patterns consist of multiple nodules of hyalin cartilage separated by normal marrow in conjunction with partial to complete encompassing plates of lamellar bone that conform to the irregular shapes of the cartilage nodules. The chondrosarcomatous patterns consist of a single confluent mass of cartilage, which commonly permeates the marrow, "trapping" host lamellar bone on all sides, and which forms bands of fibrosis between the confluent peripheral cartilage lobules. Other less common patterns included cartilagenous infiltration of the Haversian systems or marrow fat and/or the development of a soft tissue mass. A central secondary chondrosarcoma is defined as one that shows the combination of both the enchondromatous and chondrosarcomatous patterns. All 18 of the pure enchondromas diagnosed by the methods proposed in this article behaved with strict benignity (i.e., without evidence of recurrence or metastasis with an average follow-up period of 7.2 years). The 33 primary and secondary chondrosarcomas diagnosed using the described patterns behaved with the predicted frequency of recurrence, metastasis, and patient demise.  相似文献   
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One of the early diamond crimped knitted polyester (Dacron) grafts was surgically excised after implantation for 25 years in the aorto-billiac position because of false aneurysm formation at the three anastomotic sites. The sutures were no longer visible. While the areas around the false aneurysm were poorly incorporated, the graft limbs were well encapsulated with some endothelial-like cells on the luminal surface. The integrity of the graft was well preserved despite mild fraying and the disruption of one stitch.  相似文献   
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