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101.
102.
OBJECTIVES: To examine the diagnostic performance of circulating oxidized low density lipoprotein levels as a biochemical risk marker of coronary heart disease. DESIGN AND METHODS: 361 patients with coronary artery disease and 710 healthy volunteers as normal controls were examined. Receiver-operating characteristics curve analysis in addition to statistical analysis (univariate, multivariate) were done to determine the usefulness of the assay. RESULTS: Patients with coronary artery disease showed significantly elevated circulating oxidized low density lipoprotein levels. Males less than 70 years of age showed a significant association between oxidized low density lipoprotein levels and coronary artery disease. Receiver-operating characteristics curve analysis showed superior performance (e.g., sensitivity, specificity) of oxidized low density lipoprotein as a diagnostic marker of coronary artery disease as compared against other lipid markers (total cholesterol, triglyceride, high density lipoprotein, lipoprotein (a), and total cholesterol to high density lipoprotein ratio) with optimal performance in younger males. CONCLUSIONS: Oxidized low density lipoprotein levels may be a promising biochemical risk marker of atherosclerotic disease, especially in young males.  相似文献   
103.
Objective: The air was to demonstrate paravaginal defects at DeLancey's levels I, II, and III by pelvic magnetic resonance imaging scanning in patients with symptomatic pelvice relaxation preoperatively and to demonstrate the disappearance of such defects after surgical repair.Study design: Magnetic resonance imaging scans of the pelvis were performed in 12 patients exhibiting cystourethroceles and symptomatic urinary stress incontinence.Results: Magnetic resonance imaging scans of bilateral fascial defects at the upper third of the vagina (level 1) were unremarkable except for the constant “chevron sign,” whereas the middle third of the vagina (level II) displayed the “saddlebags sign,” and the lower third of the vagina (level III) displayed the “mustache sign.” These defects disappeared postoperatively.Conclusions: Bilateral defects in the paracolpium at vaginal support levels I, II, and III may be found by magnetic resonance imaging scans before surgery in certain patients with symptomatic pelvic relaxation. Postoperative scans after paravaginal repair demonstrate the disappearance of these defects.  相似文献   
104.
BACKGROUND: Local control and survival following surgical treatment of rectal cancer have been improved by the introduction of total mesorectal excision (TME). The aim of this study was to determine the nationwide impact of the introduction and training of TME on recurrence and survival in rectal cancer. METHODS: Short- and long-term outcomes of a recently published trial of rectal cancer surgery (TME trial) were compared with results from an older trial (cancer recurrence and blood transfusion (CRAB) trial), in which conventional surgery was performed without quality control. Only patients who were operated on with curative intent and who did not receive neoadjuvant radiotherapy were studied. Differences in clinicopathological characteristics were corrected for by multivariate analysis. To ensure valid comparisons, only events that occurred within 2 years of operation were analysed with regard to long-term outcome. RESULTS: In the univariate analysis, a higher clinical anastomotic leak rate was found in patients following low anterior resection in the TME trial (P = 0.046), but this association was not significant in the multivariate analysis. The local recurrence rate decreased from 16 per cent in the CRAB trial to 9 per cent in the TME trial, and type of operation (conventional (CRAB trial) versus TME (TME trial)) was an independent predictor of local recurrence (P = 0.002). Type of operation was also an independent predictor of overall survival (P = 0.019); there was a higher survival rate in the TME trial. CONCLUSION: The introduction and training of TME has led to improved long-term outcome of patients with rectal cancer in the Netherlands.  相似文献   
105.
The incidence of adenocarcinoma of the cervix increased steadily in young women in the United States between the early 1970s and the mid-1980s. Despite this increase, little is known about the etiology of this cancer, although a role for risk factors for both squamous cell carcinoma of the cervix and endometrial adenocarcinoma has been suggested. Incident cases of adenocarcinoma of the cervix diagnosed in women born after 1935 (ages 42 to 56 at diagnosis) were identified from the Los Angeles (California) County Cancer Surveillance Program (LACCSP). Data from personal interviews with 195 cases and 386 controls (matched on age, race, and neighborhood) were analyzed. Compared with women in the highest categories of education and income, women in the lowest categories had a 2.5 and 3.1-fold elevated risk of adenocarcinoma of the cervix. Number of sexual partners, especially before age 20, was strongly predictive of risk (odds ratio = 5.6, 95 percent confidence interval = 1.4–22.0 for 10 or more compared with no partners before age 20). Smoking was not associated significantly with risk. Weight gain and long-term use of oral contraceptives increased risk, while long-term diaphragm use was protective. This study suggests that both sexual and hormonal factors are important etiologic factors for adenocarcinoma of the cervix.Drs Ursin, Pike, Preston-Martin, and Peters are with the Department of Preventive Medicine, University of Southern California School of Medicine, Los Angeles, CA, USA. Dr D'Ablaing, now deceased, was with the Department of Pathology at the University of Southern California School of Medicine. Address correspondence to Dr Ursin, Department of Preventive Medicine, University of Southern California Norris Comprehensive Cancer Center, 1441 Eastlake Ave., MS#44, P.O. Box 33800, Los Angeles, CA 90033-0800, USA. This study was supported by grants P01 CA1754 and CA 44401-05 from the US National Cancer Institute, and by the California Department of Health Services, through the California Public Health Foundation, as part of its statewide cancer reporting program, mandated by Health and Safety Code Sections 210 and 211.3. The ideas and opinions expressed herein are those of the authors, and no endorsement by the State of California Department of Health Services or the California Public Health Foundation is intended or should be inferred.  相似文献   
106.
Permanent low-activity iodine-125 implants for cerebral metastases   总被引:1,自引:0,他引:1  
Beginning in 1987, selected patients with metastatic braintumors were treated with permanent implants of low-activityradioactive iodine-125 (125I) seeds. These patients underwent craniotomy,gross total resection of the metastatic lesion, andplacement of the seeds. In general, criteria fortreatment included the presence of a recurrent tumorwith a volume too large to permit radiosurgery,and a Karnofsky Performance Score of 70 orhigher. Thirteen patients underwent 14 implant procedures; allreceived external whole-brain radiotherapy. Implant dose ranged from43 Gy to 132 Gy, with a meanof 83 Gy. Survival after implantation ranged from2 weeks to almost 9 years, with amedian of 9 months. Clinical and radiographic localcontrol was obtained in 9 patients. Two patientsdied of acute, postoperative complications within a monthof implantation, so no information regarding tumor controlis available for them. Late complications included abone flap infection in one patient and aCSF leak in another; both were treated withoutfurther sequelae.These results demonstrate that permanent 125I implants canresult in good survival and quality of life,and occasionally can yield long-term survival. Potentially, itis a cost-effective treatment in that a separateprocedure for stereotactic implantation or radiosurgery is notneeded, as is the case with the useof temporary high-activity seeds. The permanent implantation itselfadds less than 10 minutes to the craniotomy,and the risk of symptomatic radiation necrosis islow. We recommend consideration of this procedure inpatients harboring large, recurrent metastatic tumors that requirefurther surgery.  相似文献   
107.
Purpose: To determine the impact of whole pelvic irradiation on the risk of PSA failure in prostate cancer patients, at high predicted risk for lymph node involvement, receiving definitive radiotherapy.

Materials and Methods: Between October 1987 and December 1995, 506 patients with clinically localized prostate cancer were treated with definitive radiotherapy at UCSF and affiliated institutions. Treatment consisted of 4-field whole pelvic irradiation followed by a prostate-only boost, or prostate-only treatment (median follow-up was 35 months and 30 months, respectively). PSA failure was defined as: 1. a PSA value ≥ 1 ng/ml; or 2. a PSA value that rose ≥ 0.5 ng/ml in ≤ 1 year posttreatment on two consecutive measurements, with the first rise defined as the time of failure. The calculated risk of lymph node positivity (%rLN+) was defined as (iPSA) + 10(GS-6), and high risk was defined as %rLN+ ≥ 15%. Univariate and multivariate analyses were performed.

Results: A total of 201 high-risk patients were identified. High-risk patients who received whole pelvic irradiation had significantly improved freedom from PSA failure compared to those who received prostate-only treatment (median PFS = 34.3 months vs. 21.0 months; p = 0.0001). Potential confounding variables, including initial PSA, Gleason score, T stage, radiation dose, year of treatment, use of three-dimensional (3D) conformal techniques, and use of hormone therapy, did not account for the observed difference in time to PSA failure. Multivariate analysis revealed type of radiation treatment to be the most significant independent predictor of outcome.

Conclusion: Whole pelvic radiotherapy significantly improves the PSA failure-free survival in patients with a high calculated risk of lymph node positivity.  相似文献   

108.

Purpose

To evaluate the prevalence of excessive screen-based behaviors among Brazilian adolescents through a systematic review with meta-analysis.

Data source

Systematic review and meta-analysis were recorded in the International Prospective Register of Ongoing Systematic Reviews (PROSPERO-CRD 2017 CRD42017074432). This review included observational studies (cohort or cross-sectional) that evaluated the prevalence of excessive screen time (i.e. combinations involving different screen-based behaviors) or TV viewing (≥2 h/day or >2 h/day in front of screen) through indirect or direct methods in adolescents aged between 10 and 19 years. The research strategy included the following databases: MEDLINE, LILACS, SciELO and ADOLEC. The search strategy included terms for “screen time”, “Brazil”, and “prevalence”. Random effect models were used to estimate the prevalence of excessive screen time in different categories.

Data summary

Twenty-eight out of 775 studies identified in the search met the inclusion criteria. The prevalence of excessive screen time and TV viewing was 70.9% (95% CI: 65.5–76.1) and 58.8% (95% CI: 49.4–68.0), respectively. There was no difference between sexes in both analyses. The majority of studies included showed a low risk of bias.

Conclusions

The prevalence of excessive screen time and TV viewing was high among Brazilian adolescents. Intervention are needed to reduce the excessive screen time among adolescents.  相似文献   
109.
Infection due to enterohemorrhagic Escherichia coli (EHEC) has not been described in immunosuppressed patients. We recently saw a case of EHEC infection caused by a novel Shiga toxin II-producing Escherichia coli serotype (O121:H19) that caused hemorrhagic colitis in a patient with renal and cardiac transplants. The patient's signs, symptoms, and colon pathology were similar to reports of EHEC infection in immunocompetent patients. This case suggests that the immunosuppressed state may not alter the clinical presentation or histopathologic findings of this disorder. Assays for EHEC are not routinely done at most hospitals. Therefore, clinicians caring for transplant patients should be aware of the typical clinical presentation of EHEC infection, so that they can initiate appropriate laboratory investigation in suspected cases. Received: 27 December 1999 Accepted: 13 September 2000  相似文献   
110.
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