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91.
Francis M. Mumbanza Marijn Bauters Elizabeth Kearsley Pascal Boeckx Constantin A. Lubini Hans Verbeeck 《Biotropica》2020,52(4):651-663
Lianas are poorly characterized for central African forests. We quantify variation in liana composition, diversity and community structure in different forest types in the Yangambi Man and Biosphere Reserve, Democratic Republic of Congo. These attributes of liana assemblages were examined in 12 1-ha plots, randomly demarcated within regrowth forest, old growth monodominant forest, old growth mixed forest and old growth edge forest. Using a combination of multivariate and univariate community analyses, we visualize the patterns of these liana assemblage attributes and/or test for their significant differences across forest types. The combined 12 1-ha area contains 2,638 lianas (≥2 cm diameter) representing 105 species, 49 genera and 22 families. Liana species composition differed significantly across forest types. Taxonomic diversity was higher in old growth mixed forests compared to old growth monodominant and regrowth forests. Trait diversity was higher than expected in the regrowth forest as opposed to the rest of forest types. Similarly, the regrowth forest differed from the rest of forest types in the pattern of liana species ecological traits and diameter frequency distribution. The regrowth forest was also less densely populated in lianas and had lower liana total basal area than the rest of forest types. We speculate that the mechanism of liana competitive exclusion by dominant tree species is mainly responsible for the lower liana species diversity in monodominant compared to mixed forests. We attribute variation in liana community structure between regrowth and old growth forests mostly to short development time of size hierarchies. 相似文献
92.
Ying Ma Shun-Xian Wang Yun Liu Guo-Guang Peng Xiao-Ming Wang Bo Zhang Bi-Hua Wu Ju-Ming Yu 《Gene》2013
Objectives
Ischemic stroke is influenced by both environmental and genetic factors. The CD40/CD40L system is related to proinflammatory and prothrombogenic responses, which are involved in the pathophysiology of ischemic stroke. The aim of this study was to evaluate association between the CD40 -1C/T single nucleotide polymorphism (SNP) and ischemic stroke in a Chinese population.Methods
We conducted a case–control study including 286 ischemic stroke patients and 336 controls. CD40 -1C/T SNP was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing methods, and evaluated its relevance to ischemic stroke susceptibility.Results
Significantly increased ischemic stroke risk was found to be associated with the T allele of CD40 -1C/T (OR = 1.273, 95% CI = 1.016–1.594). The frequencies of CT and TT/CT genotypes of CD40 -1C/T in ischemic stroke patients were significantly higher than those of controls, respectively (for CT: OR = 2.350, 95% CI = 1.601–3.449; for TT/CT: OR = 2.148, 95% CI = 1.479–3.119). And, similar results were obtained after adjusting non-matched variables. We found that the frequency of carried T genotypes (TT and TT/CT) was significantly increased in patients with history of stroke compared with patients without (for TT: OR = 6.538, 95%CI = 1.655–25.833; for TT/CT: OR = 3.469, 95%CI = 1.031–11.670), respectively.Conclusions
The findings suggested that the CD40 -1C/T polymorphism might contribute to the susceptibility to ischemic stroke in the Chinese population, and might be associated with history of previous stroke. 相似文献93.
Marijana Popović Hadžija Marina Korolija Nikolina Jemin Iva Pavković Pajica Pavković Edita Pape Medvidović Mirko Hadžija 《Gene》2013
Genetic variants of IL-18 and IL-12B may be important in immunoregulatory abnormalities, observed in the patients with Type 1 diabetes mellitus (T1DM), that contribute to individual differences in response to a treatment. Therefore, we examined the significance of IL-18-137G/C, IL-18-607C/A, and IL-12B A/C polymorphisms in Croatians (187 patients, 236 controls), not only as factors that contribute to susceptibility to T1DM, but also as determinants of the clinical presentation of disease. 相似文献
94.
《Chronobiology international》2013,30(5):1124-1134
Using structural equation modeling, it can be shown that long weekly working hours and work on weekends, nights, and in shifts have detrimental effects on psychovegetative health. Employees' reported subjective work-life balance also decreases with increasing number of hours worked/week, days worked on weekends, or at nights, and with working shifts. A decrease in work-life balance in turn increases the risk of psychovegetative impairments (PVIs). Thus, long and unusual working hours increase the risk of psychovegetative health impairments both directly and indirectly, moderated by the subjective work-life balance. In fact, the indirect effects of working time on PVIs via the work-life balance seem to be stronger than the direct effects. Results of a cross-validation study of four independent and representative samples from Germany and the European Union (N?>?50,000) indicate high structural stability of these results and thus an increased validity and range for generalization. (Author correspondence: anna. wirtz@gawo-ev. de) 相似文献
95.
《Chronobiology international》2013,30(4):361-370
Several attributes of the work schedule can increase the risk of occupational injuries and accidents, health impairments, and reduced social participation. Although previous studies mainly focused on the effects of shiftwork and long working hours on employee health and safety, there is little evidence of a potential negative impact of working Sundays on the incidence of occupational accidents, health impairments, and work-life balance. A representative sample of employed workers in 31 member and associated states of the European Union (n?=?23,934) served as the database for a cross-sectional analysis. The sample was collected via face-to-face interviews in the year 2005. The association of the risks of occupational accidents, health impairments, and decreases in work-life balance with working Sundays was calculated using logistic regression models, controlling for potential confounders, such as shiftwork, workload, and demographic characteristics. The results indicated that working one or more Sundays/month was associated with increase both in the risk of reporting one or more health impairments (odds ratio [OR]: 1.17, 95% confidence interval [CI]: 1.06–1.29) and poorer work-life balance (OR: 1.15, 95% CI: 1.02–1.28). These effects remained after controlling for potentially confounding factors, such as other work schedule attributes, intensity of physical and mental workload, and individual characteristics. Furthermore, working Sundays was also related to increased risk of occupational accidents within the last year (OR: 1.34, 95% CI: 1.03–1.73). Controlling again for individual, workload, and working-time characteristics, a significant association with accident risk, however, remained only in work sectors with low a priori risk of occupational accidents (OR: 1.40, 95% CI: 1.02–1.91), although the increased risk could be observed for both medium and high a priori risk sectors working Sundays (without controlling for additional confounders). The results thus indicate that the detrimental effects of working Sundays on safety, health, and social well-being should be taken into account when designing work schedules. The potential hazards to employees' safety, health, and work-life balance, in particular, should be considered in discussions concerning extending work on Sundays in certain sectors, e.g., retail. (Author correspondence: awirtz@hsph. harvard. edu) 相似文献
96.
Si Yan Guangjin Hou Charles D. Schwieters Shubbir Ahmed John C. Williams Tatyana Polenova 《Journal of molecular biology》2013
Microtubules and their associated proteins play important roles in vesicle and organelle transport, cell motility and cell division. Perturbation of these processes by mutation typically gives rise to severe pathological conditions. In our efforts to obtain atomic information on microtubule-associated protein/microtubule interactions with the goal to understand mechanisms that might potentially assist in the development of treatments for these diseases, we have determined the three-dimensional structure of CAP-Gly (cytoskeleton-associated protein, glycine-rich) domain of mammalian dynactin by magic angle spinning NMR spectroscopy. We observe two conformations in the β2 strand encompassing residues T43-V44-A45, residues that are adjacent to the disease-associated mutation, G59S. Upon binding of CAP-Gly to microtubule plus-end tracking protein EB1, the CAP-Gly shifts to a single conformer. We find extensive chemical shift perturbations in several stretches of residues of CAP-Gly upon binding to EB1, from which we define accurately the CAP-Gly/EB1 binding interface. We also observe that the loop regions may exhibit unique flexibility, especially in the GKNDG motif, which participates in the microtubule binding. This study in conjunction with our previous reports suggests that conformational plasticity is an intrinsic property of CAP-Gly likely due to its unusually high loop content and may be required for its biological functions. 相似文献
97.
Kelly Swanson Christine Grieshop Elizabeth Flickinger H.-P. Healy K. A. Dawson N. R. Merchen 《Archives of animal nutrition》2013,67(4):309-318
The goal of this study was to examine whether supplemental fructooligosaccharides (FOS) plus mannanoligosaccharides (MOS) influenced immune function and ileal and fecal microbial populations of adult dogs. Eight adult dogs surgically fitted with ileal cannulas were used in a crossover design. Dogs were fed 200g of a dry, extruded, kibble diet twice daily. At each feeding, dogs were dosed with either 1g sucrose (placebo) or 2g FOS plus 1g MOS orally via gelatin capsule. Fecal, ileal, and blood samples were collected at the end of each 14-d period to measure microbial populations and immune characteristics. Treatment least squares means were compared using the GLM procedure of SAS. Supplementation of FOS plus MOS increased fecal bifidobacteria and fecal and ileal lactobacilli concentrations. Dogs fed FOS plus MOS also tended to have lower blood neutrophils and greater blood lymphocytes vs placebo. Serum, fecal, and ileal immunoglobulin concentrations were unchanged by treatment. Supplementation of FOS plus MOS beneficially altered indices of gut health by improving ileal and fecal microbial ecology. Supplementation of FOS plus MOS also altered immune function by causing a shift in blood immune cells. 相似文献
98.
目的:本文的目的是研究白癜风患者的求医行为及男女性别之间的差异,分析患者选择医疗机构的原因并指导他们正确就医.方法:我们对210例白癜风患者进行问卷调查分析.访谈问卷内容包括人口统计学特征、白癜风知识、求医行为及原因、疾病的发展及心理状态的调查等.结果:仅14.3%的患者对自身疾病的基本知识回答正确,并且患者主要通过医生获得疾病知识;81.0%的患者首诊时选择公立综合医院,医疗技术水平(占69.9%)是患者在首诊时选择医疗机构的主要考虑方面,50.5%的患者存在多处求医的现象;81 4%的患者存在不同程度的心理压力.结论:白癜风患者普遍存在多处求医及不良求医行为,公立医院是目前白癜风患者的主要流向;白癜风患者的认知程度、心理状态等不容乐观;我们应针对白癜风患者多次求医和乱求医的行为及其原因开展白癜风健康教育,正规医疗机构应通过改善服务质量、提高疗效、加强宣传等促进白癜风患者正确求医. 相似文献
99.
目的:了解部队男性官兵前列腺炎的发病情况及影响因素调查。方法:采用整群分层,随机抽样,对某高原部队300名男性官兵进行问卷调查,并对官兵的生殖系统、前列腺液等进行相关检查。结果:发现前列腺炎12人,多数为已婚的干部及入伍前有女朋友的战士。约66%官兵了解生殖健康概念及内容,与被调查者的学历、职务、是否来自城市等有关;对性传播疾病的病种及传播途径了解不够的官兵达20%。结论:部队官兵的生殖健康良好,少数有前列腺炎,最好定期进行生殖系统疾病筛查;部队官兵对生殖健康概念及内容了解尚可,但还应加强宣传教育。 相似文献
100.
Gladys N. Honein-AbouHaidar Nancy N. Baxter Rahim Moineddin David R. Urbach Linda Rabeneck Arlene S. Bierman 《Cancer epidemiology》2013,37(6):946-956
Background: Participation in screening tests for colorectal cancer (CRC) is generally low in Ontario, Canada. In addition, inequities in participation exist including lower participation among low-income individuals, males and individuals living in rural areas. In April 2008, Colon Cancer Check (CCC) program, the province-wide CRC screening program, was launched in Ontario. This study describes the trends and inequities in CRC screening participation three years before and three years after the CCC, and assesses the effect of the program on CRC screening participation, overall and among certain population groups. Methods: We used administrative data to identify cohorts of individuals eligible for CRC screening in fiscal years 2005–2011. We calculated the age-standardized percent of Fecal Occult Blood Test (FOBT) participation, large bowel endoscopy participation, and being ‘up-to-date’ with CRC screening tests. Results: From 2005 to 2011, FOBT participation increased from 7.6% to 14.8%, large bowel endoscopy participation from 3.4% to 5.7%, and ‘up-to-date’ with CRC screening from 27.2% to 41.3%. Before the launch of the CCC program, the quarterly increase in FOBT participation was 0.07% (p = 0.19), increased immediately after the launch (1.8%, p < 0.01), followed by a decline (?0.08%, p = 0.08), returning to its pre-program increase rate. We noted a significant decrease in FOBT participation every summer (?0.44%, p < 0.01). The CCC program had minimal effect on large bowel endoscopy participation. Before the launch of the CCC program, the quarterly increase in ‘up-to-date’ with CRC screening was 0.9% (p < 0.01), increased immediately after the launch (2.5%, p = 0.05), followed by a modest decline thereafter (?0.59%, p < 0.02). From 2005 to 2011, recent residents living in low-income neighborhoods were consistently and significantly less likely to have a FOBT and be ‘up-to-date’ with CRC screening than long-term residents living in high-income neighborhoods (2.9–4.5%; 14.7–17.3% respectively). Pre-CCC inequities in CRC participation persisted after the launch of the program. Conclusion: CRC testing was increasing in Ontario from 2005. An immediate increase in CRC testing, FOBT in particular, occurred after the launch of the CCC program, followed by a return to its pre-CCC increase rate thereafter. Future efforts are needed to improve screening participation and address inequities. 相似文献