丹参主要居群的遗传关系及药材道地性的初步研究

目的 研究丹参主要居群的遗传关系及药材的道地性问题。方法 选择丹参主要产地样本44个（包括9个居群样本），进行RAPD分析，得到的扩增条带用NTSYS－pc和AMOVA软件进行数据处理。结果 （1）从100多个引物中选择出11个多态性强和重复性好的引物，扩增得到129条带；（2）不同居群内多态位点比率为20.9%－55.0%；（3）用UPGMA法得到所有样本的聚类图，可分为6个主要分支组和3个组外个体，其中四川中江居群的5个样本聚为一组，并与其他样本遗传距离较大；（4）按产地分组，遗传差异的80.44%存在于居群内，8.29%来自于组内居群间，11.27%的遗传差异来自于组间。结论 （1）丹参居群内遗传多样性十分丰富；（2）山东和河南的栽培居群栽培种源来自于当地野生居群，尚没有进行人工选择，丹参酮ⅡA等成分的减少的原因主要是栽培条件不理想；（3）地区间居群的遗传分化不均衡，四川中江和河北承德居群与其他居群距离较远；（4）丹参的道地性的确定应当依据现代的优质药材评价系统，山东和河南产的丹参也可主为是丹参的道地药材。     

The importance of the patient-clinician relationship in adherence to antiretroviral medication

The aim of the study was to assess dimensions of the patient-clinician relationship in relation to adherence with antiretroviral medication in a sample of HIV patients. This was a correlational evaluation, using a cross-sectional design. Thirty-eight HIV patients in two UK HIV units provided complete data. Analysis suggested that the elements of the patient-clinician relationship contributing to adherence with medication were the patient perception of being valued and respected by the clinician, the patients' ability to initiate discussions about the treatment, empowerment and level of trust placed in the nurse. The latter, and the time since starting antiretroviral treatment, were the only two variables that could predict adherence in a regression model, explaining 41% of the variance in adherence. Building trusted relationships with the patients and investing in educational and communication techniques to improve the therapeutic relationship could strongly contribute to HIV patients to maintaining high adherence rates.     

Gender specific activation patterns of trunk muscles during whole body tilt

Gender specific differences as evidenced in both anthropometric data and physical performance of healthy persons have been broadly demonstrated. Recently advancements in surface electromyography (SEMG) have shown possible differences in men’s and women’s muscle coordination patterns. However, quantitative information about gender related muscle co-ordination patterns are rare. This investigation was carried out to both verify if trunk muscle SEMG amplitude–force relationship differs between men and women and refine techniques of measurement and data analysis using SEMG. Thirty-one healthy volunteers (16 women, 15 men) were investigated during whole body tilt at angles from 5° to 90° (from quasi vertical to horizontal position). Subjects had to maintain body in body axis while their lower body was fixed and the upper body remained unsupported. SEMG was taken from five different trunk muscles of both sides simultaneously. At corresponding tilt angles women exhibited higher amplitude levels of their abdominal muscles in comparison to men, who were characterized by higher back muscle amplitudes. Abdominal muscles showed a non-linear SEMG amplitude–force relationship but differed between genders with more linearity in women. Back muscles showed a linear amplitude–force relationship with no differences between genders. Women were characterized by higher levels of co-contraction of all investigated muscles. The data are in accordance with histological investigations, which already proved specific fiber distribution patterns in both abdominal and back muscles and gender related differences in relative area of Type 1 fibers of back muscles. The observed differences in SEMG–force relationship for the abdominal muscles remain hypothetical because of lack of histological information.     

Aggression and the composition of conflicting pairs in green monkeys

Aggressive behavior was studied in green monkeys kept in two groups in corrals in the Adler Primate Center. Studies addressed the effects of the composition of conflicting pairs, the nature of the relationship, relatedness, and hierarchical relationships between antagonists on the intensity and structure of their aggressive interactions. The frequency of contact aggression was found to be essentially independent of the composition of the conflicting pairs. At the same time, the frequency of non-contact aggressive events was sensitive to such factors of the conflicting pairs as the gender assignments of antagonists, membership of one or another maternal line, quality of relationships, and social ranking. __________ Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 92, No. 8, pp. 984–989, August, 2006.     

Pulsed radio-frequency electromagnetic fields: dose-dependent effects on sleep, the sleep EEG and cognitive performance

To establish a dose-response relationship between the strength of electromagnetic fields (EMF) and previously reported effects on the brain, we investigated the influence of EMF exposure by varying the signal intensity in three experimental sessions. The head of 15 healthy male subjects was unilaterally exposed for 30 min prior to sleep to a pulse-modulated EMF (GSM handset like signal) with a 10 g-averaged peak spatial specific absorption rate of (1) 0.2 W kg(-1), (2) 5 W kg(-1), or (3) sham exposed in a double-blind, crossover design. During exposure, subjects performed two series of three computerized cognitive tasks, each presented in a fixed order [simple reaction time task, two-choice reaction time task (CRT), 1-, 2-, 3-back task]. Immediately after exposure, night-time sleep was polysomnographically recorded for 8 h. Sleep architecture was not affected by EMF exposure. Analysis of the sleep electroencephalogram (EEG) revealed a dose-dependent increase of power in the spindle frequency range in non-REM sleep. Reaction speed decelerated with increasing field intensity in the 1-back task, while accuracy in the CRT and N-back task were not affected in a dose-dependent manner. In summary, this study reveals first indications of a dose-response relationship between EMF field intensity and its effects on brain physiology as demonstrated by changes in the sleep EEG and in cognitive performance.     

Similarities and reciprocal influences in eating behavior within sibling pairs: a longitudinal study

The present study investigated similarities and reciprocal influences in emotional, external and restrained eating in adolescent siblings, and the moderating role of sex and quality of relationship. A total of 415 sibling pairs (aged 13-16 years) participated in this two-wave one-year longitudinal study. Analyses were conducted by means of Structural Equation Modeling. Cross-sectional findings demonstrated that siblings are moderately similar in their eating behavior. Longitudinal findings showed that the younger siblings exert a small influence on the emotional and external eating behavior of the older siblings. No support was found for the older siblings affecting the younger siblings in their eating behavior. Furthermore, no sex differences were found in the associations between sibling eating behaviors within and over time. However, we did find a moderating effect for the quality of the relationship concerning similarities in emotional eating. Future research focusing on various sociocultural influences on adolescents' eating behaviors should also include younger siblings.     

When, what and how South Australian pre-registration junior medical officers' career choices are made

OBJECTIVES: This study aimed to provide better understanding of how pre-registration junior medical officers (PJMOs) make their career choices by investigating when decisions are made, what factors impact on choices, and the role of experience in this process. METHODS: A third (n = 54) of PJMOs from the 2003 cohort at South Australian teaching hospitals participated in the current research. Inductive content analysis was used to discover themes in data gathered from semistructured interviews. RESULTS: Interviews revealed that although 26% (14/54) of participants had made their career decisions in their pre-registration year, 50% (27/54) had still to decide on a career choice. The factors identified as impacting on career choice were grouped into 5 main categories: job satisfaction; lifestyle; career path; training programme, and the wider environment. Depending on the demographic profile of the PJMO, different relative importance was assigned to these factors. The most important elements used to confirm or disconfirm PJMOs' potential career choices were the experiences they had of different specialty areas. DISCUSSION: This study allowed an in-depth exploration of the factors that affect the decision-making process of PJMOs. It also found that defined groups of PJMOs place different degrees of importance on these factors, which may have implications for medical workforce planning. It is clear that experience and role models are a crucial component of the career decision-making process. This has importance for specialties that are not incorporated into junior medical training.     

Exposure–response relationship between endotoxin exposure and lung function impairment in cotton textile workers

OBJECTIVES: Preventive workplace regulations are so far not based on an ubiquitously accepted threshold for airborne endotoxin in the bioaerosol. METHODS: In a cross-sectional study, 150 employees of a cotton spinning mill underwent lung function testing. Furthermore, in a random subset of 75 textile workers cross-shift lung function test and methacholine challenges were performed. Airborne current endotoxin exposure was classified as "low", "medium", and "high" (100-450 Endotoxin Units (EU)/m(3), respectively) based on endotoxin activity. RESULTS: The exposure-response relationship between current endotoxin exposure and prevalence of an obstructive ventilation pattern was significant (test for linear trend: P = 0.019); the adjusted odds ratio for high endotoxin exposure was 11.22 (95% confidence interval 1.03-121.17). Within individuals, FEV(1)/FVC% was significantly reduced after the shift (paired t test: P = 0.009) but not related to current endotoxin exposure. Twelve workers showed bronchial hyperresponsiveness (8.1% before and 12.2% after the work shift; Fisher's exact test: P = 0.021). CONCLUSION: The study among German cotton textile workers suggests an exposure-dependent effect of current endotoxin exposure on lung function impairment with significant effects above 450 EU/m(3).     

Adolescent cancer patients’ perceived quality of cancer care: The roles of patient engagement and supporting independence

Objectives

A lack of focus on variation in engagement among cancer populations of differing developmental stages led us to examine the associations between patient engagement, the patient-provider relationship, cognitive development, readiness to transition to adulthood (transitional readiness) and perceived quality of care.