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11.
New combinations for three species ofPolypleurum have been proposed. The Apinagia type of embryo sac is recorded for the first time in a species ofPolypleurum, P. filifolium. The Dicraea type of embryo sac found inP. dichotomum andP. munnarensis has been reinterpreted and renamed as the Polypleurum type. The embryo sac types met with in the family are discussed. The nucellar plasmodium organizes before the embryo sac attains maturity in all the three investigated species.  相似文献   
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ObjectiveTo describe the prevalence of Helicobacter pylori (H. pylori) infection in Latin Americaand the Caribbean (LAC), through systematic review and meta-analysis by age groups and gender.MethodsSystematic review and meta-analysis of the population-based observational epidemiological studies carried out in LAC, focused on the prevalence of H. pylori and published until March, 2018. The databases utilized in the search were MEDLINE, SCIELO andPUBMED. The prevalence described in the meta-analysis and 95% confidence intervals were estimated by the random effects model, and weighted by the size of the study.ResultsThe 22 selected studies were carried out in 14 countries of LAC, and included 24,178 individuals. The studies were conducted between 1987 and 2012, and all were representative of at least one city. The prevalence of H. pylori infection was 57.57% (CI95%:50.43;64.72) for all ages; in children and adolescents the prevalence was 48.36% (CI95%:38.03;58.70) and in adults 69.26%(CI95%:64.54;76.99). No differences were observed regarding sex.ConclusionPrevalence of H. pylori infection in LAC is high for all age groups. These data reinforce the necessity of actions towards the prevention and treatment of H. pylori infection for all age groups. Treating H pylori infection in young ages probably will reduce gastric cancer incidence in the future.  相似文献   
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目的对糖尿病患者肠道菌群特征及其相关性进行系统评价。方法检索知网、维普、万方、PubMed、Cochrane library、Embase等数据库关于糖尿病患者肠道菌群特征及其相关性的文献,同时追踪纳入文献的参考文献,时限为2009年3月至2019年3月,采用统一提取表,由两名研究者独立按照规定的纳入排除标准进行文献提取和方法学质量评估。最后采用RevMan 5.3软件进行Meta合并,Stata 12.0软件进行亚组分析与发表性偏倚识别。结果共纳入25篇研究,合计2 209例患者。Meta分析显示:(1)糖尿病患者菌群总量(SMD=-0.30,P=0.53)、乳杆菌数量(SMD=-0.79,P=0.20)下降,拟杆菌数量(SMD=1.43,P=0.12)、梭菌数量(SMD=0.28,P=0.40)增加,差异均无统计学意义,双歧杆菌数量(SMD=-1.82,P=0.02)下降,差异有统计学意义。(2)糖尿病患者菌群Shannon指数I~2=91%,r=-0.21[-0.32,0.09],P0.05;Chao1指数I~2=0%,r=-28.17[-40.85,-15.48],P0.05;均下降。(3)拟杆菌、双歧杆菌、梭菌与空腹血糖的相关性分别为:I~2=0%,r=-0.15[-0.27,-0.03];I~2=0%,r=-1.16[-1.42,0.91];I~2=0%,r=-0.28[-0.42,-0.14],均P0.05。而乳杆菌的相关性差异无统计学意义:I~2=47%,r=-0.00[-0.30,0.29],P=0.98。(4)乳杆菌和拟杆菌与炎症因子(TNF-α、IL-6)呈负相关,乳杆菌(r=-0.43;r=-0.60),P0.05;拟杆菌(r=-0.58;r=-0.58),P0.05,差异有统计学意义。结论糖尿病患者肠道菌群总量无明显变化,但有益菌含量和多样性下降,拟杆菌、双歧杆菌和梭菌含量与血糖水平呈负相关,而乳杆菌无相关,其结果还需要大样本、高质量的研究加以论证。  相似文献   
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Adherence to medication among individuals with chronic obstructive pulmonary disease (COPD) is suboptimal and has negative impacts on survival and health care costs. No systematic review has examined the effectiveness of interventions designed to improve medication adherence. Electronic databases Medline and Cochrane were searched using a combination of MeSH and keywords. Eligible studies were interventions with a primary or secondary aim to improve medication adherence among individuals with COPD published in English. Included studies were assessed for methodological quality using the Effective Practice and Organisation of Care (EPOC) criteria. Of the 1,186 papers identified, seven studies met inclusion criteria. Methodological quality of the studies was variable. Five studies identified effective interventions. Strategies included: brief counselling; monitoring and feedback about inhaler use through electronic medication delivery devices; and multi-component interventions consisting of self-management and care co-ordination delivered by pharmacists and primary care teams. Further research is needed to establish the most effective and cost effective interventions. Special attention should be given to increasing patient sample size and using a common measure of adherence to overcome methodological limitations. Interventions that involve caregivers and target the healthcare provider as well as the patient should be further explored.  相似文献   
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A variety of epidemiologic studies have focused on the association between macrophage migration inhibitory factor (MIF) gene − 173G/C polymorphism and inflammatory bowel disease (IBD). However, results in different studies have been inconsistent. In order to derive a more precise estimation of the associations, we performed this meta-analysis and systematic searches of electronic databases PubMed and Web of Science (up to April 30, 2013). Based on our search criteria, a total of seven eligible studies concerning the MIF − 173G/C polymorphism and IBD risk were included in the final meta-analysis, comprising 2162 IBD cases and 2134 controls. Significant association was found between MIF − 173G/C polymorphism and the risk of IBD when all studies were pooled into the meta-analysis (for C allele vs. G allele: OR = 1.25, 95% CI = 1.12–1.41, p = 0.000; for C/C vs. G/G: OR = 1.71, 95% CI = 1.23–2.39, p = 0.002; for C/C + G/C vs. G/G: OR = 1.24, 95% CI = 1.09–1.42, p = 0.002; for C/C vs. G/C + G/G: OR = 1.67, 95% CI = 1.20–2.33, p = 0.002). Heterogeneity and publication bias did not exist in the overall comparisons. The present meta-analysis suggests an association between the MIF − 173G/C polymorphism and IBD risk. However, due to few studies and the selection bias existed in some studies, the results should be interpreted with caution.  相似文献   
18.
Free energy calculated in simulations on the atomic level (Monte Carlo or Molecular Dynamics) has a systematic error, if the water shell surrounding a globular protein is finite. The error (“cluster error”) is equal to a difference of free energies obtained in simulations with an infinite and finite water shell. In this work a continuum dielectric model was used to estimate the “cluster error”. A multipole expansion of the estimate was performed for a water shell with a spherical outer boundary. The expansion has very simple form. Each term is a product of two functions, one of them depending only on the charge's conformation, and the other one only on dielectric properties of the system. There are two practical uses of the expansion. First, it may be used to estimate the “cluster error” in a simulation already made; second, it may be used to plan a simulation in such a way that the “cluster error” is minimal. Numerical values of the largest terms in the multipole expansion corresponding to a typical system in simulations of globular proteins are given.  相似文献   
19.
Most anthropogenic activities impacted on water quality and quantity, and further impacted on ecosystem services (ESs) in watershed are related to land use and climate changes those may cause losses of ecosystem functions. Effective information regarding ESs and their optimal priority conservation planning responded to land use and climate changes provide useful support for diverse stakeholders in ESs planning, management and policies. This study integrated the approach of spatially explicit ESs (water yield, inorganic nutrient, organic nutrient and sediment retentions) by using hydrology and material flow model (Soil and Water Assessment Tools, SWAT model) into systematic conservation of hydrological ESs according to land use and climate changes in Teshio watershed located in the north of Hokkaido, Japan. We investigated the spatial patterns and the hotspots of ESs changes to determine the spatial pattern of changes in systematic conservation optimal area of ES protection in terms of ESs protection targets. Under the land use and climate change scenarios, the forest land use significantly affected on the water yield, sediment, organic-Nitrogen (N) and organic-Phosphorous (P) retentions. The agricultural land (paddy and farmland fields) impacted on the inorganic-N and inorganic-P retentions. We applied the systematic conservation model (MARXAN model) to optimize the area for management of hydrological ESs satisfied the protection targets (30% and 50% of potential maximum ESs values among all scenarios) in all and individual ecosystem services, respectively. The simulated results indicated that the areas of spatial optimal ESs protection for all hydrological ESs were totally different from those for individual ESs. For bundles of ESs, the optimal priority conservation areas concentrated in southwest, north, and southeast of this watershed, which are related to land use, topography and climate driving factors. These places could guarantee ESs sustainability from both environmental protection and agricultural development standpoints. The priority conservation area turned more compact under climate change because the increased precipitation and temperature increased ESs amount. For individual ESs, the optimal priority conservation areas of water yield, sediment retention and organic nutrient retention were traded off against those of inorganic nutrient retention (lower Jaccard's indexes and negative correlations of selection times). Especially, the negative correlation of selection times increased as the conservation target increased from 30% to 50%. The proposed approach provided useful information for assessing the responses of ESs and systematic conservation optimal planning to the land use and climate changes. The systematic conservation optimal areas of hydrological ESs provided an effective trade-off tool between environmental protection (sediment and organic nutrient retentions) and economic development (water yield and inorganic nutrient retention).  相似文献   
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BackgroundRosacea is a chronic inflammatory disorder affecting millions of individuals worldwide. Diagnosis is based on signs and symptoms with management and treatment aimed to suppress inflammatory lesions, erythema, and telangiectasia. While many clinical trials of rosacea exist, the lack of consensus in outcome reporting across all trials poses a concern. Proper evaluation and comparison of treatment modalities is challenging. In order to address the inconsistencies present, this project aims to determine a core set of outcomes which should be evaluated in all clinical trials of rosacea.Methods/designThis project will utilize a methodology similar to previous core outcome set research. A long list of outcomes will be extracted over four phases: (1) systematic literature review, (2) patient interviews, (3) other published sources, and (4) stakeholder involvement. Potential outcomes will be examined by the Steering Committee to provide further insight. The Delphi process will then be performed to prioritize and condense the list of outcomes generated. Two homogenous groups of physicians and patients will participate in two consecutive rounds of Delphi surveys. A consensus meeting, composed of physicians, patients, and stakeholders, will be conducted after the Delphi exercise to further select outcomes, taking into account participant scores. By the end of the meeting, members will vote and decide on a final recommended set of core outcomes. For the duration of the study, we will be in collaboration with both the Core Outcome Measures in Effectiveness Trials (COMET) and Cochrane Skin Group - Core Outcome Set Initiative (CSG-COUSIN).DiscussionThis study aims to develop a core outcome set to guide assessment in clinical trials of rosacea. The end-goal is to improve the reliability and consistency of outcome reporting, thereby allowing sufficient evaluation of treatment effectiveness and patient satisfaction.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1554-3) contains supplementary material, which is available to authorized users.  相似文献   
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