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1.
Potentilla erecta (L.) is known for the high concentration of proanthocyanidin oligomers (PAs) in its underground parts. The use of its preparations as food supplements and the lack of chemical–analytical studies concerning with an efficient chromatographic separation procedure for these compounds led us to develop a strategy to profile PAs occurring in this species.  相似文献   
2.
OBJECTIVES: To examine the effect of black race and acute (negative life events) and chronic (lack of social support) psychological stress on the risk of herpes zoster in late life. DESIGN: A population-based, prospective cohort study. SETTING: Central North Carolina. PARTICIPANTS: Duke Established Populations for Epidemiological Studies of the Elderly, a stratified probability sample of community-dwelling persons more than 65 years of age. MEASUREMENTS: Interviewers administered a comprehensive health survey to the participants in 1986-1987 (P1, n = 4162), 1989-1990 (P2, n = 3336), and 1992-1994 (P3, n = 2568). Incident cases of zoster between P1 and P2 and P2 and P3 served as the dependent variable. Hypothesis-testing variables included race, negative life events, and five measures of social support. Control variables included age, sex, education, cancer, chronic diseases, basic ADLs, instrumental ADLs, depression, self-rated health, hospitalization, and cigarette smoking. Statistical analyses employed chi-square tests and proportional hazards model. RESULTS: At baseline, the sample had a mean age of 73.6 years and was 55% black, 45% white, and 65% female. There were 65 cases of zoster between P1 and P2 and 102 cases of zoster between P2 and P3. From P1 to P2, 1.4% of blacks and 3.4% of whites developed zoster (P < .001). From P2 to P3, 2.9% of blacks and 7.5% of whites developed zoster (P < .001). After controlling for the above variables, blacks were significantly less likely to develop zoster (adjusted risk ratio = 0.35; 95% confidence interval (CI), 0.24-0.51; P < .001). Negative life events increased the risk of zoster, but the result was borderline for statistical significance (adjusted RR = 1.38, 95% CI 0.96-1.97; P = .078). No measures of social support were significantly associated with zoster. CONCLUSION: Black race decreased the risk of zoster in late life significantly. Measures of stress were not significantly related to zoster, but study limitations preclude definitive conclusions. Future research should focus on these factors in larger samples and different populations.  相似文献   
3.
BACKGROUND: Sleepiness related car accidents are common in obstructive sleep apnoea syndrome (OSAS) patients. The objective measurements of sleepiness used in clinical setting quantify the tendency to fall asleep in quiet situations that are completely different from driving. METHODS: We studied 30 OSAS patients with subjective (subjective sleepiness scales) and objective (multiple sleep latency test, MSLT) sleepiness measurements, associated with driving simulation test (DST), previously validated in young healthy subjects. The results of subjective and objective sleepiness tests were compared with simulated driving performance in order to evaluate the suitability of our DST for measuring alertness. RESULTS: Subjective and objective sleepiness measurements were significantly correlated with driving performance on the simulator. The most significant correlates of sleepiness were the measures of the primary vehicle control task on the simulator: lane position variability and crash data. The comparison of DST and MSLT results suggested our driving simulated approach could be used to evaluate daytime sleepiness in the clinical setting of OSAS patients. CONCLUSIONS: Our DST is a suitable objective tool to detect sleepiness in OSAS patients, and could be useful in the clinical setting of sleep medicine and research.  相似文献   
4.
The pBR322 recombinant plasmids DNA products, which purified by phenol-extract and equilibrium centrifugation in CsCl-ethidium bromide gradients, have been shown as mainly spatial conformation of covalently closed circular DNA (i.e. cccDNA) by agarose gel electrophoresis for homogeneity detection. Laser Raman spectra in the region 450-1750 cm-1 have been obtained for the circular double-stranded plasmids DNA molecule in an aqueous solution, indicating not only contain those marker peaks of secondary structure as in conventional B-form of DNA, but also present both 854 and 1083 cm-1 diagnostic bands of reflecting the vibration state of deoxyribosyl phosphodiester backbone. The present analysis have demonstrated relationship between the superhelical state for cccDNA and the two conformational marker bands that can be considered as the tertiary structure marker on plasmids DNA. Because of markedly Raman hypochromicity of charecter band 1378cm-1 of dT in contrast to liear DNA molecule, as well as the carbonyl double bond vibration line of dT have shifted to higher wave number position, the base stacking analysis represent occurrence of both increase in staking reaction activity of dT, and injury of a number of the Hoogsteen hydrogen bond between dA and dT with exist supercoil structure in cccDNA.  相似文献   
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The purpose of this study was to investigate coming out to family and friends and their relationships to shame, internalized heterosexism, lesbian identity, and perceived social support in Chinese lesbians from 2 different cultural settings—Mainland China (N = 244) and Hong Kong (N = 234). Results of structural equation modeling showed that, in both samples, a sense of shame was related to internalized heterosexism and a devaluation of one’s lesbian identity, which in turn was related to a decreased likelihood of coming out to others. Shame was also associated with a reduced perception of support from friends, which seemed in turn to exacerbate internalized heterosexism among lesbians. Family support was generally unrelated to outness, except for outness to friends in the Hong Kong sample. Results are discussed in relation to the cultural stigma attached to same-sex orientation and the cultural practice of shaming that parents use to socialize children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Nutritional status in patients with neuroendocrine tumours (NETs), especially of gastroenteropancreatic origin, can be deeply affected by excessive production of gastrointestinal hormones, peptides, and amines, which can lead to malabsorption, diarrhoea, steatorrhea, and altered gastrointestinal motility. Besides, the surgical and/or medical management of NETs can lead to alteration of gastrointestinal secretory, motor, and absorptive functions, with both dietary and nutritional consequences. Indeed, disease-related malnutrition is a frequently encountered yet both underrecognized and understudied clinical phenomenon in patients with NETs, with substantial prognostic and socioeconomic consequences. Most of these conditions can be alleviated by a tailored nutritional approach, also with the aim of improving the efficacy of cancer treatments. In this setting, skilled nutritionists can play a fundamental role in the multidisciplinary health care team in NETs management and their presence should be recommended. The aim of this review is to provide dietary advices for each specific condition in patients with NETs, underlining the importance of a nutritional approach to treat malnutrition in this setting. Further, we will provide preliminary evidence coming from our data on the assessment of nutritional status in a single cohort of patients with NETs.  相似文献   
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Dr.Ben,你好。单位上原有一台掌上电脑(PPC),最近添置了一个蓝牙GPS接收模块,但通过蓝牙配对之后,使用导航地图存在问题。在网上看到很多朋友说要调整GPS模块的COM通讯端口,但是我怎样才能知道蓝牙模块在使用哪个COM端口?总不能一个一个试吧。  相似文献   
10.
Pizza 《微型计算机》2009,(21):56-59
一说到黑盒处理器,大家可能很快想到AMD PhenomII X4 955 BE、940BE这样的旗舰型号,但在此之前,一些入门级产品中同样存在口碑不错的黑盒产品,如Athlon X27750BE/7850BE等。但很可惜,入门级的黑核产品线很久都没有更新过了,这也让那些喜欢尝鲜但口袋不够富裕的AMD粉丝们等得望穿秋水……还好,大家的等待是值得的,  相似文献   
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