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51.
青年学者常常在完成资料收集和分析之后对获得的结果充满了激情。然而,在开始写作论文时,这种热情常常锐减。事实也如此,国家级学术会议的论文数远高于最终发表的医学文献数。优秀的研究成果不能发表的原因2大多在于写作新手在开始写作时对写作的认识混乱和畏缩。一般产生畏缩的原因有2个:要么是研究者不知从何着手,要么是不知如何组织文章结构。不过,大部分放射学论文的写作均有规律可寻,在很大程度上是程式化的。本文试图介绍一种可应用于典型放射学论文的逐段写作法。如果初学者能够完成按照本文教授的18段写作,其论文将具有合理的结构,… 相似文献
52.
Background
Violence affects the lives of millions of women worldwide, in all socioeconomic classes. Violence and the fear of violence are emerging as important risk factor contributing to the vulnerability to human immunodeficiency virus (HIV) infection for women. The objective of the present cross sectional study is to compare the experiences of domestic violence between HIV-positive and HIV-negative married women seeking treatment in a tertiary care hospital.Methods
The study is conducted in a tertiary care hospital in Pune on a randomly selected 150 married women (75 HIV-positive and 75 HIV-negative). Informed consent was obtained from all the women and also a trained counsellor was present during the process of data collection. The data was collected by interview method by taking precautions as laid down in the World Health Organization's ethical and safety recommendations for research on domestic violence and using modified conflict tactics scale (CTS). The definition of violence followed is as per the Declaration on the Elimination of Violence against Women, adopted by the United Nations General Assembly in 1993.Results
The percentage of women reporting domestic violence is 44.7% (95% confidence interval [CI] = 36.84–52.68). The proportion of physical, emotional and sexual violence reported is 38% (95% CI = 30.49–45.96), 24% (95% CI = 17.67–31.31), and 14.7% (95% CI = 9.66–21.02), respectively. The odds of reporting violence of all forms is significantly higher among HIV-positive women than among HIV-negative women (P<0.05). Univariate and multivariate logistic regression is carried out to examine the possible predictors of domestic violence.Conclusion
The findings suggest high proportion of HIV-positive women report violence then HIV-negative women which must be addressed through multilevel prevention approaches. 相似文献53.
Marcia S. Driscoll Thomas M. Ludden Daniel T. Casto Louis C. Littlefield 《Journal of pharmacokinetics and pharmacodynamics》1989,17(2):141-168
Routine clinical pharmacokinetic data collected prospectively from pediatric patients receiving theophylline were analyzed using the NONMEM (nonlinear mixed effects model) digital computer program. A total of 314 measured serum theophylline concentrations (STCs) were obtained from 84 hospitalized patients ranging in age from 4 months to 15.2 years with the majority of patients between the ages of 1 and 8 years. Fifty-six percent were male. The race/ethnicity distribution was 71.4% Latin, 15.5% black, 11.9% Caucasian, and 1.2% (one subject) Pakistani. Of the total number of observed STCs, 16.2% reflected some degree of outpatient dosing. The pharmacokinetic model used was a one-compartment open model with either zero-order or first-order absorption and first-order elimination. Age was the most important determinant of theophylline clearance (Cl);weight was inferior to age and did not statistically improve the model (p>0.005when combined with age. Total Clincreased by 10%/year over the age range of 1 to 15 years of age. Black race and male gender were associated with higher Clvalues: for a given age, Clwas 34% higher for blacks than the reference population composed of the remaining patients, and Clfor males was 25% higher than that for females. The volume of distribution (Vdfor the population was estimated to be 0.62 L/kg. The interindividual variability in Cland Vdexpressed as coefficients of variation were 19 and 28%, respectively. The residual intraindividual error variance corresponded to a standard deviation of 2.8 g/ml. The STCs that represented some degree of outpatient dosing were 21 % lower than those reflecting only inpatient dosing. Alternate models that include weight as a determinant of theophylline clearance are also provided. The NONMEM method of determining population pharmacokinetics is well suited to the pediatric population since it does not require a large number of STCs per patient. In this study a mean of only 3.7 STCs per patient were utilized to provide information which should prove useful in the design and adjustment of theophylline dosage regimens in children. 相似文献
54.
PURPOSE: To determine whether metaphases arising at different times after mitogen stimulation of G0 lymphocytes differ in frequencies of X-ray-induced chromosome aberrations. MATERIALS AND METHODS: Human G0 lymphocytes from peripheral blood exposed to 0, 1.5 or 3.0 Gy X-rays were stimulated to divide with the mitogen phytohaemagglutinin (PHA). First-division metaphases were distinguished from second and third divisions by chromatid labelling with 5-bromodeoxvuridine (BUdR) and staining with Giemsa or DAPI. Cultures harvested 48, 70 and 94 h after mitogen stimulation were analysed for unstable aberrations on Giemsa-stained slides and for stable and unstable aberrations by fluorescence in situ hvbridization (FISH) with painting probes for chromosomes 1, 2 and 4. RESULTS: Frequencies of aberrations declined at the later culture periods, as expected on the basis of unstable aberrations being lost in mitotic division. Whe n scoring was restricted to firstdivision metaphases, however, aberration frequencies were higher in 94-h cultures than in 48-h cultures. CONCLUSIONS: Frequencies of radiation-induced chromosome aberrations in first-division metaphases increase with culture time after mitogen stimulation. Possible explanations for this finding are a delay of damaged cells in mitogenic response or progression through divisions and heterogeneity among lymphocytes in culture kinetics and radiosensitivity. The data argue against the common assumption that all first-division cells are equivalent as indicators of radiation-induced chromosome aberrations. 相似文献
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58.
Amelia E. Talley Kenneth J. Sher Andrew K. Littlefield 《Addiction (Abingdon, England)》2010,105(7):1235-1245
Aims The current study examined developmental changes in substance use behaviors (SUBS) based upon sexual orientation. The analyses also attempted to address a number of methodological limitations in the extant longitudinal literature (i.e. distinct operationalizations of sexual orientation, timing of sexual orientation assessment with respect to reports of SUBs, non‐linear growth). Participants Data were drawn from a longitudinal study of incoming first‐time college students at a large public university (n = 3720). Design After a paper‐and‐pencil assessment just prior to matriculation, participants completed a web‐based survey every fall and spring for 4 years (sub‐sample n = 2854). Findings Latent growth models revealed that sexual minorities demonstrated significant heterogeneity with regard to substance use trajectories. Initial levels and trajectories of the frequency of substance use for sexual minority individuals were distinct, generally, from their exclusively heterosexual peers. Methodologically, the timing of the assessment of sexual orientation influenced the results, and modeling non‐linear components indicated that sexual minorities are at risk for exponential increases in their frequency of certain SUBs over time (i.e. drunkenness; cannabis use). Conclusions Sexual minority and majority individuals exhibited differences in SUBs during emerging adulthood, especially when using self‐identification to define sexual orientation. Individuals who endorsed a sexual minority self‐identification at the onset of emerging adulthood, as opposed to 4 years later, evidenced exponential increases in rates of drunkenness and cannabis use. These results support that the timing of assessment is important and that some trajectories of sexual minority SUBs are non‐linear during this developmental period. 相似文献
59.
Gavidia-Payne S Littlefield L Hallgren M Jenkins P Coventry N 《The Australian and New Zealand journal of psychiatry》2003,37(2):204-211
OBJECTIVE: To assess the impact of inpatient intervention, provided by a child mental health unit in Victoria, Australia, on a number of key child and family variables. METHOD: Pre-post test design with a four-month follow up was applied to assess changes across time. Twenty-nine parents, 42 teachers, and 37 referrers provided reports on a series of child, parent, and family functioning measures. RESULTS: Significant improvements in child behaviour and functioning, parenting competency and efficacy, parenting practices, and reduced parental depression were observed over time. Changes in family functioning scores were not significant; however, univariate analysis indicated improvements in two individual subscales. CONCLUSIONS: There is a lack of studies of the outcome of inpatient interventions of children in psychiatric settings. However, as shown in the present study, improvements in functioning can be detected and obtained with short-term interventions that focus on both children and families. Methodological shortcomings (i.e. absence of comparison groups) and lack of specificity in intervention variables, however, are difficulties yet to be overcome in evaluation research of inpatient treatment. 相似文献
60.
Objective : To evaluate the efficacy of biliary‐enteric bypass in the palliation of malignant hilar biliary obstruction. Materials and Methods : Records of 19 patients from 1995 to 1998 were reviewed. There were 13 patients with cholangiocarcinoma and 6 patients with carcinoma of the gallbladder. Single biliary‐enteric bypass had been performed in 13 of the patients; the rest had more than one biliary‐enteric anastomosis. Results : The 30‐day mortality was 21% (4/19 patients). Bile leakage occurred in 2 patients, leading, in both, to fatality. Excluding the 30‐day mortality, the median survival of patients with carcinoma of the gallbladder and cholangiocarcinoma was 116 days (43–200) and 202 days (47–1207), respectively. The mean hospital stay was 31 days (13–59) and all patients were discharged with their symptoms relieved and a drop in bilirubin of at least two‐thirds their pre‐operative level. The late complication rate was 26.7% (4/15 patients). Conclusion : Biliary‐enteric bypass is effective in the palliation of symptoms of patients suffering from unresectable hilar biliary obstruction, although it carries considerable mortality and morbidity. Stenting, rather than surgery, should be considered for patients with unresectable gallbladder cancer. 相似文献