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82.
Archives of Sexual Behavior - Gender variance is a broad term used to describe gender non-conforming behaviors. Past studies have used the parental response to Child Behavior Checklist (CBCL) Item...  相似文献   
83.
Wound microbiology and associated approaches to wound management   总被引:20,自引:0,他引:20       下载免费PDF全文
The majority of dermal wounds are colonized with aerobic and anaerobic microorganisms that originate predominantly from mucosal surfaces such as those of the oral cavity and gut. The role and significance of microorganisms in wound healing has been debated for many years. While some experts consider the microbial density to be critical in predicting wound healing and infection, others consider the types of microorganisms to be of greater importance. However, these and other factors such as microbial synergy, the host immune response, and the quality of tissue must be considered collectively in assessing the probability of infection. Debate also exists regarding the value of wound sampling, the types of wounds that should be sampled, and the sampling technique required to generate the most meaningful data. In the laboratory, consideration must be given to the relevance of culturing polymicrobial specimens, the value in identifying one or more microorganisms, and the microorganisms that should be assayed for antibiotic susceptibility. Although appropriate systemic antibiotics are essential for the treatment of deteriorating, clinically infected wounds, debate exists regarding the relevance and use of antibiotics (systemic or topical) and antiseptics (topical) in the treatment of nonhealing wounds that have no clinical signs of infection. In providing a detailed analysis of wound microbiology, together with current opinion and controversies regarding wound assessment and treatment, this review has attempted to capture and address microbiological aspects that are critical to the successful management of microorganisms in wounds.  相似文献   
84.
The effects of measurement errors on relative risk regressions   总被引:8,自引:0,他引:8  
This paper concerns the effects of random error in numerical measurements of risk factors (covariates) in relative risk regressions. When not dependent on outcome (nondifferential), such error usually attenuates relative risk estimates (shifts them toward one) and leads to spuriously narrow confidence intervals. The presence of measurement error also reduces precision of estimates and power of significance tests. However, significance levels obtained by using the approximate measurements are usually valid and as powerful as possible given the measurement error. The attenuation in risk estimate depends not only on the size (variance) of the measurement error, but also on its distributional form, on whether it is dependent on the true level of the risk factor (whether it is of "Berkson" type), on the variance and distributional form of true levels of the risk factor, on the functional form of the regression (exponential or linear), and on the confounding variables included in the model. Error in measuring confounding variables leads to loss of control of confounding, leaving residual bias. Uncomplicated techniques of correcting the effects of measurement error in simple models in which distributions are assumed normal are available in the statistical literature. For these corrections, information on measurement error variance is required. Some approaches appropriate for more general models have been proposed, but these appear to be insufficiently developed for routine application.  相似文献   
85.
This national study was designed to gather baseline data about the reading activities of registered nurses. Questionnaires were administered by nurse continuing educators to subjects (N = 1406) at 44 sites in 25 states and the District of Columbia. In a week, the mean amount of time devoted to professional literature was four hours, 48 minutes (SD = 3.88) plus eight hours, 12 minutes (SD = 5.15) to general material. This translated to reading one hour and 51 minutes per day, slightly more than the average adult. Educational level, position, and memberships were the best predictors of how much time was spent reading job-related material that might lead to self-development and enhancement of nursing practice.  相似文献   
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The toxicities and oxidative stress-inducing actions of (−)-nicotine and smokeless tobacco extract (STE), containing equivalent amounts of nicotine, were studied. Toxicities were determined by colony formation assays using Chinese hamster ovary (CHO) cells. Results indicated that nicotine is less toxic than smokeless tobacco extract that contained the same amount of nicotine. The generation of reactive oxygen species, following treatment with smokeless tobacco extract and nicotine, was assessed by measurement of changes in glutathione (GSH) and malondialdehyde (MDA) levels. CHO cells (5 × 105 cells/5 ml media) were incubated with 4, 0.8, and 0.08 mg of nicotine and STE containing the same amounts of nicotine. All preparations of smokeless tobacco extract significantly decreased GSH levels and increased MDA generation. However, 0.08 mg of nicotine treatment did not result in a significant change in GSH level, and only 4 mg of nicotine were sufficient to increase MDA generation. Addition of free radical scavenging enzymes, superoxide dismutase (SOD) and catalase (CAT), and an intracellular GSH precursor, N-acetyl-L-cysteine (NAC), replenished the GSH levels in nicotine-treated cells. GSH levels in cells exposed to smokeless tobacco extract containing 4 and 0.8 mg nicotine remained significantly lower than the control with the addition of SOD and CAT. However, co-addition of NAC with smokeless tobacco extract preparations returned the GSH levels to the control level. Lactate dehydrogenase (LDH) activities were measured in the media to establish the membrane damage following exposure to smokeless tobacco extract and nicotine. Treatment of cells with 4 mg nicotine caused a significant increase in LDH activity, which was returned to control level in the presence of the antioxidant enzymes and NAC. Smokeless tobacco extract did not change the LDH activity. Received: 14 September 1998/Accepted: 24 February 1999  相似文献   
89.
The numbers of women of childbearing age in the US with HIV and AIDS from heterosexual transmission continues to rise. Behavioral interventions remain the best means of preventing transmission of HIV. Program planners often implement interventions to promote behavioral change in a wide range of settings such as family planning or sexually transmitted disease clinics, drug treatment facilities, or medical facilities that serve high risk and HIV positive women. Women recruited in different types of settings, however, may differ with respect to their experience with, attitudes toward, and willingness to use condoms and contraception. Such differences should be considered when tailoring interventions to the populations being served. We examined the readiness to use condoms and contraception among 3784 women in four cities recruited in three different types of settings: community, facilities not targeted to HIV positive women and medical facilities for HIV positive populations. Readiness to use condoms or contraception was measured using The Transtheoretical Model of Change. Women reported being in different stages along the continuum of condom and contraceptive use in the three settings. A greater proportion of women in the HIV-facility, 45%, had used condoms consistently for the previous 6 months compared to women in the other two settings (12% and 11%). Similarly, variation across settings was seen for contemplation of consistent contraceptive use to prevent unintended pregnancies. The variability in the distribution of condom and contraceptive use across settings underscores the importance of assessing the readiness for the behavior change and designing interventions that meet the specific needs of the populations being served.  相似文献   
90.
The size frequency distributions of diffuse, primitive and classic beta-amyloid (Abeta) deposits were studied in single sections of cortical tissue from patients with Alzheimer's disease (AD) and Down's syndrome (DS) and compared with those predicted by the log-normal model. In a sample of brain regions, these size distributions were compared with those obtained by serial reconstruction through the tissue and the data used to adjust the size distributions obtained in single sections. The adjusted size distributions of the diffuse, primitive and classic deposits deviated significantly from a log-normal model in AD and DS, the greatest deviations from the model being observed in AD. More Abeta deposits were observed close to the mean and fewer in the larger size classes than predicted by the model. Hence, the growth of Abeta deposits in AD and DS does not strictly follow the log-normal model, deposits growing to within a more restricted size range than predicted. However, Abeta deposits grow to a larger size in DS compared with AD which may reflect differences in the mechanism of Abeta formation.  相似文献   
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