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91.
T L Nagel J A Stolk D W Alderman R Schoenborn M P Schweizer 《Magnetic resonance in medicine》1990,13(2):271-278
The crossover surface coil is constructed with two turns of copper foil using a unique transposition construction which incorporates an explicit center tap ground of the widened bottom layer. The coil reduces dielectric and inductive losses by effective shielding of electric fields and uniform distribution of magnetic fields for minimum Q losses upon loading of the coil. Flexible, copper foil construction permits easy conformation to tissues of interest, enhancing coil performance. Construction details of the crossover coil and Q data for coils of various sizes operating at a number of frequencies are given. 相似文献
92.
A modified Western blot (WB) that includes both shared (r21e) and unique recombinant envelope proteins from human T-lymphotropic virus (HTLV) type I (rgp46I) and type II (rgp46II) was compared to conventional HTLV serologic tests in 379 United States blood donors and individuals residing in diverse geographic regions, and the specimens were categorized as positive (n = 158), indeterminate (n = 158), or negative (n = 63) for HTLV infection. Of the 158 HTLV-I/II-positive specimens (66 requiring radioimmunoprecipitation assay [RIPA] for confirmation), 156 reacted concordantly with r21e, gag, and either rgp46I or rgp46II, thus eliminating the need for RIPA in all but two specimens and yielding a test sensitivity of 98.7 percent. Of the 158 indeterminate and 63 negative specimens, none reacted with r21e and rgp46I or rgp46II, yielding a test specificity of 100 percent. Furthermore, analysis of an additional 184 consecutive specimens from a retrovirology reference laboratory demonstrated that the modified WB correctly identified 27 of 28 HTLV-I specimens and all 13 HTLV-II specimens, with a test sensitivity of 97.6 percent. None of specimens that were indeterminate or nonreactive in conventional WB and/or RIPA and none of the screening enzyme immunoassay-negative specimens reacted with r21e and either rgp46I or rgp46II, for a test specificity of 100 percent. Thus, the modified WB appears to be highly sensitive and specific for simultaneous detection and discrimination of HTLV-I from HTLV-II and has the advantage of being a one-step assay that is easily performed in all types of laboratory settings and allows rapid, reliable, and standardized testing for HTLV-I/II infection. 相似文献
93.
Beulens JW Stolk RP van der Schouw YT Grobbee DE Hendriks HF Bots ML 《Diabetes care》2005,28(12):2933-2938
OBJECTIVE: This study aimed to investigate the relation between alcohol consumption and type 2 diabetes among older women. RESEARCH DESIGN AND METHODS: Between 1993 and 1997, 16,330 women aged 49-70 years and free from diabetes were enrolled in one of the Dutch Prospect-EPIC (European Prospective Study Into Cancer and Nutrition) cohorts and followed for 6.2 years (range 0.1-10.1). At enrollment, women filled in questionnaires and blood samples were collected. RESULTS: During follow-up, 760 cases of type 2 diabetes were documented. A linear inverse association (P = 0.007) between alcohol consumption and type 2 diabetes risk was observed, adjusting for potential confounders. Compared with abstainers, the hazard ratio for type 2 diabetes was 0.86 (95% CI 0.66-1.12) for women consuming 5-30 g alcohol per week, 0.66 (0.48-0.91) for 30-70 g per week, 0.91 (0.67-1.24) for 70-140 g per week, 0.64 (0.44-0.93) for 140-210 g per week, and 0.69 (0.47-1.02) for >210 g alcohol per week. Beverage type did not influence this association. Lifetime alcohol consumption was associated with type 2 diabetes in a U-shaped fashion. CONCLUSIONS: Our findings support the evidence of a decreased risk of type 2 diabetes with moderate alcohol consumption and expand this to a population of older women. 相似文献
94.
95.
96.
To determine the incidence of transfusion-associated human immunodeficiency virus (HIV) infection after routine screening of donated blood, a pilot study estimated the pretransfusion prevalence of HIV infection among blood product recipients in San Francisco. Among the 911 nonduplicate pretransfusion specimens from recipients without a clinical history of acquired immune deficiency syndrome (AIDS) or AIDS-related complex (ARC), the overall prevalence of antibody to HIV was 2.9 percent (5.2% among males and 0.6% among females; p = 0.00002). If recipients in specifically defined or possible high-risk groups (n = 348) were excluded, a seropositivity rate of 1.8 percent (10/563) was detected, with all the positives occurring in men (10/242, 4.1%) and none in women (0/321, 0%). This demonstrated prevalence of HIV infection among blood product recipients in San Francisco before transfusion was substantially higher than the known 0.02 to 0.04 percent prevalence in the donor population. Therefore, the population of women without known risk for AIDS is the best in which to assess the risk of HIV infection in patients who are currently receiving seronegative blood transfusions. 相似文献
97.
98.
Erkens JA Klungel OH Stolk RP Spoelstra JA Grobbee DE Leufkens HG 《Diabetes care》2001,24(8):1428-1432
OBJECTIVE: To investigate cardiovascular drug use and hospitalizations attributable to type 2 diabetes from 1 year before until 6 years after the start of oral antidiabetic therapy. RESEARCH DESIGN AND METHODS: In this cohort study, 2,584 patients with type 2 diabetes were selected from the PHARMO Record Linkage System, comprising pharmacy records and hospitalizations for all 320,000 residents of six Dutch cities. Patients with type 2 diabetes were identified as incident oral antidiabetic drug users between 1992 and 1997. Nondiabetic subjects were 1:1-matched for age, sex, pharmacy, and index date and received no insulin, oral antidiabetic drugs, or glucose-testing supplies. RESULTS: Patients with type 2 diabetes were more likely to use cardiovascular drugs (RR 1.28 [95% CI 1.23-1.34]) and to be hospitalized because of cardiovascular diseases (1.54 [1.33-1.78]) after the start of oral antidiabetic therapy than nondiabetic subjects. Differences between patients with type 2 diabetes and nondiabetic subjects lessened from 1 year before until 6 years after the start of oral antidiabetic therapy, reflected by decreasing attributable risks for diuretics, beta-blockers, calcium channel blockers, and cardiac and antithrombotic drugs. The difference in use of angiotensin-converting enzyme inhibitors and lipid-lowering drugs increased. Cardiovascular hospitalizations attributable to type 2 diabetes were approximately 50% in the years close to the start of oral antidiabetic treatment and decreased to approximately 33% in the following years. CONCLUSIONS: Although cardiovascular drug use and hospitalizations remained increased in patients with type 2 diabetes after the start of oral antidiabetic therapy, cardiovascular drug use attributable to type 2 diabetes decreased after the start of oral antidiabetic therapy, especially beta-blockers, whereas cardiovascular hospitalizations first decreased and then stabilized. 相似文献
99.
目的:观察胸腰段椎弓根CT测量在椎弓根螺钉内固定中的作用,寻找一种个体化椎弓根螺钉置入的方法。方法:选择1999-02/2006-03河北工程大学附属医院收治的T12和/或L1段骨折患者59例,行螺旋CT检查及图像三维重建,重建结束后,得到胸腰段标本的三维图像,通过旋转和切割进行图像处理并测量,模拟出T11~L2的椎弓根形态,根据CT测量椎弓根的实际投照点进行调整,即横断面上椎弓根轴线与矢状位上椎弓根轴线的交点,在确定进钉点时选择下关节突为参照物,选用合适直径的螺钉进行植钉,植入螺钉后,连接棒或板系统。结果:262个椎弓根行植钉术,242个完全在椎弓根内,仅有20个螺钉穿透椎弓根皮质。术后平均随访16.1个月,均无临床并发症的发生,Frankel平均增加1.4级。术后有2例患者出现断钉(3枚),1例患者出现断棒,所植入的螺钉与机体生物相容性好,无不良反应的发生。结论:利用三维CT测量的数据辅助,严格按照个体化的椎弓根的轴线方向植钉,在置钉时应考虑到螺钉本身直径的因素,可以提高植钉的成功率。 相似文献
100.
Health-related quality of life and treatment satisfaction in Dutch patients with type 2 diabetes 总被引:12,自引:0,他引:12
Redekop WK Koopmanschap MA Stolk RP Rutten GE Wolffenbuttel BH Niessen LW 《Diabetes care》2002,25(3):458-463
OBJECTIVE: To estimate the health-related quality of life (HRQOL) and treatment satisfaction for patients with type 2 diabetes in the Netherlands and to examine which patient characteristics are associated with quality of life and treatment satisfaction. RESEARCH DESIGN AND METHODS: For a sample of 1,348 type 2 diabetes patients, recruited by 29 general practitioners, we collected data regarding HRQOL. This study was performed as part of a larger European study (Cost of Diabetes in Europe - Type 2 [CODE-2]). We used a generic instrument (Euroqol 5D) to measure HRQOL. Treatment satisfaction was assessed using the Diabetes Treatment Satisfaction Questionnaire. RESULTS: Patients without complications had an HRQOL (0.74) only slightly lower than similarly aged persons in the general population. Insulin therapy, obesity, and complications were associated with a lower HRQOL, independent of age and sex. Although higher fasting blood glucose and HbA1c levels were negatively associated with HRQOL, these factors were not significant after adjustment for other factors using multivariate analysis. Overall treatment satisfaction was very high. Younger patients, patients using insulin, and patients with higher HbA1c levels were less satisfied with the treatment than other patients. CONCLUSIONS: Obesity and the presence of complications are important determinants of HRQOL in patients with type 2 diabetes. 相似文献