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931.
蓝雨  席丽艳  张军民 《菌物学报》2019,38(8):1223-1229
随着近年来银屑病的发病率逐步增加,关于银屑病病因的研究更加深入。除了遗传、免疫和环境等相关因素,微生物与银屑病的关系也备受关注。关于真菌感染与银屑病的相关性研究始于19世纪,认为糠秕马拉色菌可能是银屑病的致病因子,与银屑病的发生发展密切相关。随后也有研究指出白念珠菌通过超抗原等作用诱发或加重银屑病。但银屑病患者依据自身IL-17增高的特点可以起到一定抵抗微生物感染的作用,因此真菌感染与银屑病的关系暂无定论。随着近年来关于两者之间关系的研究逐渐增多,真菌感染仍是银屑病患者不可忽视的诱发或加重因素之一。明确真菌感染在银屑病患者体内的作用有助于更好地研究银屑病的发病机制以及改善预后。  相似文献   
932.
以小麦(Triticum aestivum L.)双端体3DL为细胞学标记,用具有phKL基因的小麦地方品种“开县罗汉麦”为受体连续回交,将促进小麦外源部分同源染色体西己对的phKL基因和Ph2基因缺失重组在一起获得了重组体phKL Ph2^-。这种重组体有正常的育性。与只有phKL基因的小麦材料相比,重组体与外源物种Aegilops variabilis Eig.或黑麦(Secale cereale L.)杂种的部分同源染色体配对水平显著增加,表明Ph2基因的缺失体与phKL基因可能存在加性效应。部分同源染色体配对水平的增加农现在棒状二价体、环状二价体和三价体的数量变多而单价体数量减少。单价体的减少主要足由于棒状二价体的增加所造成的。在小麦外源遗传转移中,运用重组体phKL Ph2^-可能比单纯应用Ph2缺铁或phKL基因材料更理想。当与具有phlb基因的材料比较时发现,重组体phKL Ph2^-与Ae,variabilis(或黑麦)杂种的部分同源染色体配对水平显著降低,这丰要是由环状二价体和多价体的减少造成的,但是棒状二价体数量表现增加(与Ae.variabilis杂种)或达到类似水平(与黑麦杂种),这一有趣的发现从表现型上证明了Ph1基因与Ph2或phKL基因在诱导部分同源染色体配对时的遗传作用机制存在差异。  相似文献   
933.
西双版纳热带雨林树种多样性的尺度效应   总被引:1,自引:0,他引:1  
兰国玉  朱华  曹敏 《西北植物学报》2012,32(7):1454-1458
基于西双版纳20hm2森林动态监测样地内直径≥1cm的树种资料,分析了该样地树种香农多样性指数和辛普森多样性指数及其方差和变异系数在7个取样尺度(5m×5m、10m×10m、20m×20m、25m×25m、50m×50m、100m×100m、200m×250m)的变化规律,结果表明:(1)香农指数-面积曲线在尺度100m×100m有一个峰值,而辛普森指数-面积曲线在尺度为20m×20m有一个峰值。(2)香农指数和辛普森指数的方差随尺度的增加而减小,其中香农指数的方差在尺度100m×100m上最小,辛普森指数在尺度20m×20m方差最小,表明香农多样性指数在100m×100m的尺度上所获得的多样性信息比较可靠,而辛普森指数在20m×20m的尺度上所获得信息比较可靠。(3)多样性指数的方差和变异系数远大于随机模型拟合的数值,说明样地内树种不是随机分布。  相似文献   
934.
The movements we make with our hands both reflect our mental processes and help to shape them. Our actions and gestures can affect our mental representations of actions and objects. In this paper, we explore the relationship between action, gesture and thought in both humans and non-human primates and discuss its role in the evolution of language. Human gesture (specifically representational gesture) may provide a unique link between action and mental representation. It is kinaesthetically close to action and is, at the same time, symbolic. Non-human primates use gesture frequently to communicate, and do so flexibly. However, their gestures mainly resemble incomplete actions and lack the representational elements that characterize much of human gesture. Differences in the mirror neuron system provide a potential explanation for non-human primates' lack of representational gestures; the monkey mirror system does not respond to representational gestures, while the human system does. In humans, gesture grounds mental representation in action, but there is no evidence for this link in other primates. We argue that gesture played an important role in the transition to symbolic thought and language in human evolution, following a cognitive leap that allowed gesture to incorporate representational elements.  相似文献   
935.
金银花是大宗药材,市场掺伪时有发生,但目前的检测方法不能满足快速准确的检测需求,因此亟需建立快精准的检测方法。为了确立高精准度和大通量的金银花掺伪鉴别检测方法,结合SNP标记及焦磷酸测序分型分析技术,对金银花及其常见伪品差异性SNP位点进行PCR扩增及焦磷酸测序分析。结果发现,运用焦磷酸测序技术对金银花和山银花的差异性SNP位点进行定量分析,能够对金银花真伪及掺伪量进行鉴定。该方法兼有PCR技术的灵敏性和焦磷酸测序技术的准确性,具有重复性好、自动化程度较高、易操作的特点,能在3小时之内完成金银花成分掺伪量的检测工作,并得出量化结果。  相似文献   
936.
为了分析远志皂苷与莲心碱对七氟烷诱发新生大鼠急性和远期认知功能损伤的改善作用及机制,将36只新生SD大鼠随机分为中药组(n=12)、模型组(n=12)和空白组(n=12),中药组、模型组暴露于2.5%七氟烷环境中麻醉诱导2 h·d-1,连续3 d,空白组暴露在不含七氟烷的相同环境中,中药组于麻醉前30 min腹腔注射远志皂苷与莲心碱1:1配伍溶液(30 mg·kg-1),模型组和空白组腹腔注射等量0.9%氯化钠溶液,比较各组大鼠血气指标、皮质脑电图结果、Morris水迷宫行为和血清皮质酮含量,并采用Western blot法检测海马Bcl2、Bax和Caspase?3表达水平。中药组大鼠皮质脑电图癫痫波总时长、平均时长以及数量均低于模型组(P<0.05);定位航行实验结果显示,中药组大鼠逃避潜伏期短于模型组(P<0.05);空间探索实验结果显示,中药组大鼠探索时间长于模型组(P<0.05);中药组大鼠血清皮质酮含量低于模型组(P<0.05);中药组大鼠海马组织Bcl2/Bax表达水平高于模型组(P<0.05),cleaved Caspase?3表达水平低于模型组(P<0.05)。结果表明,远志皂苷与莲心碱可改善七氟烷诱发新生大鼠急性和远期认知功能损伤,其机制可能与调控凋亡相关基因Bcl2、Bax和Caspase?3表达水平有关。  相似文献   
937.

Background

Age at sexual debut is a key behavioural indicator used in HIV behavioural surveillance. Early age at menarche may precipitate early sex through perceived readiness for sex, or through school drop-out, but this is rarely studied. We investigated trends and circumstances of sexual debut in relation to schooling and age at menarche.

Methods and Findings

A cross-sectional sexual behaviour survey was conducted on all individuals age 15–59 within a demographic surveillance site in Karonga District, Malawi. Time trends were assessed using birth cohorts. Survival analysis was used to estimate the median age at menarche, sexual debut and first marriage. The 25th centile was used to define “early” sex, and analyses of risk factors for early sex were restricted to those who had reached that age, and were done using logistic regression. Of the 8232 women and 7338 men resident in the area, 88% and 78%, respectively, were seen, and, 94% and 92% of these were interviewed. The median reported age at first sex was 17.5 for women and 18.8 for men. For women, ages at menarche, sexual debut and first marriage did not differ by birth cohort. For men, age at sexual debut and first marriage decreased slightly in later birth cohorts. For both men and women increased schooling was associated with later sexual debut and a longer delay between sexual debut and first marriage, but the associations were stronger for women. Earlier age at menarche was strongly associated with earlier sexual debut and marriage and lower schooling levels. In women early sexual debut (<16 years) was less likely in those with menarche at age 14–15 (odds ratio (OR) 0.31, 95%CI 0.26–0.36), and ≥16 (OR 0.04, 95%CI 0.02–0.05) compared to those with menarche at <14. The proportion of women who completed primary school was 46% in those with menarche at <14, 60% in those with menarche at 14–15 and 70% in those with menarche at ≥16. The association between age at menarche and schooling was partly explained by age at sexual debut. The association between age at menarche and early sex was not altered by adjusting for schooling.

Conclusions

Women with early menarche start sex and marry early, leading to school drop-out. It is important to find ways to support those who reach menarche early to access the same opportunities as other young women.  相似文献   
938.

Objectives

We tested the a priori hypothesis that self-perceived and real presences of risks for colorectal cancer (CRC) are associated with better knowledge of the symptoms and risk factors for CRC, respectively.

Methods

One territory-wide invitation for free CRC screening between 2008 to 2012 recruited asymptomatic screening participants aged 50–70 years in Hong Kong. They completed survey items on self-perceived and real presences of risks for CRC (advanced age, male gender, positive family history and smoking) as predictors, and knowledge of CRC symptoms and risk factors as outcome measures, respectively. Their associations were evaluated by binary logistic regression analyses.

Results

From 10,078 eligible participants (average age 59 years), the mean knowledge scores for symptoms and risk factors were 3.23 and 4.06, respectively (both score range 0–9). Male gender (adjusted odds ratio [AOR] = 1.34, 95% C.I. 1.20–1.50, p<0.01), self-perception as not having any risks for CRC (AOR = 1.12, 95% C.I. 1.01–1.24, p = 0.033) or uncertainty about having risks (AOR = 1.94, 95% C.I. 1.55–2.43, p<0.001), smoking (AOR 1.38, 95% C.I. 1.11–1.72, p = 0.004), and the absence of family history (AOR 0.61 to 0.78 for those with positive family history, p<0.001) were associated with poorer knowledge scores (≤4) of CRC symptoms. These factors remained significant for knowledge of risk factors.

Conclusions

Male and smokers were more likely to have poorer knowledge but family history of CRC was associated with better knowledge. Since screening of these higher risk individuals could lead to greater yield of colorectal neoplasm, educational interventions targeted to male smokers were recommended.  相似文献   
939.
刘利敏  郭晓东  江岚  李新颖  王玲  张慧  田宏  兰云 《生物磁学》2013,(24):4770-4772
摘要目的:探讨在特需病房护理工作中所面临的相关问题及相应的解决办法。方法:选取2010年11月至2012年11月在我院特需病房接受过“一切以病人为中心”的护理观念和人性化护理方式的1000例相关病症患者的临床资料,并对患者在护理过程中的护理方式的满意度评价等进行回顾性分析。结果:该护理方法得到了患者以及患者家属的一致好评。在我院接受特需病房护理的1000例患者中,有900例(90.00%)患者表示非常愿意接受该种护理方法。有950例(95.00%)患者的家属也十分赞同该护理方法。但仍有部分患者在护理过程中对人性化护理有更高的要求,这对于护理人员是一个重大的挑战;另外,特需病房护理人员的素质以及专业技能也存在不足;护理环境以及护理方法仍存在些许漏洞。结论:本着“一切以病人为中心”的原则,结合患者的相关病症及相应需求采用人性化的护理模式,与患者以及患者家属进行合理的沟通。在进行特需病房患者的护理过程中注重人性化对于患者的康复具有重要的意义。  相似文献   
940.
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