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41.
Sylvie Naar-King Kathryn Wright Jeffrey T Parsons Maureen Frey Thomas Templin Phebe Lam Debra Murphy 《AIDS education and prevention》2006,18(1):1-11
This study piloted a brief individual motivational intervention targeting multiple health risk behaviors in HIV-positive youth aged 16-25. Interviews about sexual behavior and substance use and viral load testing were obtained from 51 HIV-positive youth at baseline and post intervention. Youth were randomized to receive a four-session motivational enhancement intervention (N = 25) or to a wait-list control (N = 26). Of the eligible youth approached, 88% agreed to participate, and 80% percent of participants completed at least three of four sessions. The treatment group showed significantly greater reductions in unprotected sex acts and in viral load compared with controls. Although change scores for substance use were not significantly different between the two groups, paired t tests demonstrated that reductions in alcohol use and marijuana use were significant for the treatment group at the trend level. There were no significant differences in substance use from baseline to posttest for the control group. Findings demonstrate the potential of a brief motivational enhancement intervention to improve health risk behaviors in HIV-positive youth. Larger randomized clinical trials are warranted. Resources required for retention should not be underestimated. 相似文献
42.
The effects of progesterone treatment on bupivacaine arrhythmogenicity in beating rat heart myocyte cultures and on anesthetized rats were determined. After determining the bupivacaine AD50 (the concentration of bupivacaine that caused 50% of all beating rat heart myocyte cultures to become arrhythmic), we determined the effect of 1-hour progesterone HCl exposure on myocyte contractile rhythm. Each concentration of progesterone (6.25, 12.5, 25, and 50 micrograms/ml) caused a significant and concentration-dependent reduction in the AD50 for bupivacaine. Estradiol treatment also increased the arrhythmogenicity of bupivacaine in myocyte cultures, but was only one fourth as potent as progesterone. Neither progesterone nor estradiol effects on bupivacaine arrhythmogenicity were potentiated by epinephrine. Chronic progesterone pretreatment (5 mg/kg/day for 21 days) caused a significant increase in bupivacaine arrhythmogenicity in intact pentobarbital-anesthetized rats. There was a significant decrease in the time to onset of arrhythmia as compared with control nonprogesterone-treated rats (6.2 +/- 1.3 vs. 30.8 +/- 2.5 min, mean +/- SE). The results of this study indicate that progesterone can potentiate bupivacaine arrhythmogenicity both in vivo and in vitro. Potentiation of bupivacaine arrhythmia in myocyte cultures suggests that this effect is at least partly mediated at the myocyte level. 相似文献
43.
Rupak Mukherjee Preecha Laohakunakorn M. Charles Welzig Kathryn S. Cowart J. Philip Saul 《Journal of interventional cardiac electrophysiology》2003,9(3):309-315
Background: Radiofrequency (RF) lesion size in vitro is positively correlated with applied power and catheter tip temperature. However, the relation between RF lesion size, power, and tip temperature in vivo remains unclear. We hypothesized that due to flow, anatomy and tip contact effects in vivo, increased tip temperature would be inversely related to applied power and RF lesion size.
Methods: RF lesions were created on the endocardium of 16 pigs using 5, 6, and 7 Fr catheters. The ablation generator was set to achieve a temperature of 70°C. RF lesions were created in different regions of the heart so as to encompass a wide range of blood flow and catheter movement conditions. RF lesions were measured acutely (DIMEN, mm) and correlated with average power applied (POWER, W), and average tip temperature (TEMP, °C). The POWER and TEMP relation was also examined.
Results: For TEMPs below 55°C, the power output from the generator was typically maximized at 50 W. At TEMPs above 55°C, POWER decreased exponentially with increasing TEMP {POWER = 50 – exp(-((41-TEMP)/7)), r = 0.98, p < 0.05}. Further, DIMEN tended to be inversely related to TEMP (Slope: –0.07 ± 0.04, r = –0.15, p = 0.07); but, was positively related to POWER (Slope: 0.04 ± 0.02, r = 0.23, p < 0.05). These relations varied by tip size and estimated local blood flow characteristics.
Conclusion: In vivo, variable tissue contact and flow yield DIMEN-POWER-TEMP relations opposite to those found in vitro. These counterintuitive results suggest that maximum in vivo RF lesion size is achieved when power is maximized at tip temperatures between 50 and 60°C. 相似文献
44.
Adel M. Mansour Robert W. Frenck Jr. Toni Darville Isabelle A. Nakhla Thomas F. Wierzba Yehia Sultan Magdy I. Bassiouny Kathryn McCarthy Richard F. Jacobs 《Clinical and Vaccine Immunology : CVI》2005,12(2):363-365
Cerebrospinal fluid gamma interferon (IFN-γ) and interleukin-10 levels in 39 patients with tuberculous meningitis were serially measured. Cytokine levels did not predict intracranial granuloma (IG) development, but IFN-γ levels in the top quartile after 1 month of therapy were highly associated (odds ratio = 18) with detection of an IG by computed tomography scanning. 相似文献
45.
46.
Background
Persisting neck pain is common in society. It has been reported that the prevalence of neck pain in office workers is much higher than in the general population. The costs to the worker, employer and society associated with work-related neck pain are known to be considerable and are escalating. The factors that place office workers at greater risk of developing neck pain are not understood. The aim of this study is to investigate the incidence and risk factors of work-related neck pain in Australian office workers. 相似文献47.
48.
Perspectives on HIV/AIDS epidemiology and prevention from the Eighth International Conference on AIDS. 下载免费PDF全文
The Eighth International AIDS Symposium in Amsterdam, the Netherlands, provided updated scientific and programmatic information on the human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) to thousands of interested participants. As in the other scientific areas, the amount of information presented in epidemiology and prevention was overwhelming; however, the scientific progress described was steady but incremental. This commentary summarizes progress made in three selected areas that were highlighted during the meeting's scientific session and a fourth that received widespread media attention: (1) the epidemiology of HIV/AIDS in heterosexual women; (2) tuberculosis as an increasing opportunistic pathogen in HIV-infected persons; (3) prevention research, practice, and policy; and (4) preliminary reports of severe immunodeficiency in persons without evident HIV infection. In order to stem HIV transmission worldwide, a safe and effective vaccine is urgently needed. Currently, in the absence of such a vaccine, it is crucial for all of the world's communities to apply the best science-based prevention methods available. 相似文献
49.
Managing recurrent urinary catheter blockage: problems, promises, and practicalities. 总被引:2,自引:0,他引:2
Kathryn Getliffe 《Journal of wound, ostomy, and continence nursing》2003,30(3):146-151
Long-term urinary catheterization is rarely completely free of complications, and encrustation by mineral salts leading to catheter blockage is common in around 40% to 50% of long-term catheterized patients. Recurrent blockage is a problem, which is both distressing to patients and caregivers and costly to health services in terms of time and resources. This article addresses the causes of recurrent urinary catheter blockage, proactive approaches to care, and the evidence for use of catheter maintenance solutions to reduce buildup of mineral deposits. 相似文献
50.
This paper describes the ring-opening methathesis polymerization of homopolymers and copolymers of exo- and endo-2-cyanobicyclo[2.2.1]hept-5-ene (norbornenenitrile) in solution. Polymerization kinetics were followed via 1H NMR spectroscopy in real time while the final polymer microstructure was determined via 13C NMR. While pure endo monomer does not polymerize readily, it copolymerizes with exo monomer, rapidly and to high conversions. The structure of the copolymer appears to be quite similar to that of exo homopolymer. We conclude that exo monomer adds directly to either exo or endo, while endo-endo addition is sterically hindered. 相似文献