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991.
目的:研究口服胃肠超声助显剂检测2型糖尿病患者胃半排空功能的临床价值。方法:选取2011年8月至2013年8月已被收治的符合标准的2型糖尿病患者共100例作为研究组,同时选取110例健康志愿者作为对照组,采用口服胃肠超声助显剂分别检测2组受试者胃半排空功能,记录分析两组受试者胃窦部面积减少一半的时间。结果:研究组的15min、30min、45min、60min、75min、90min的胃排空率均低于对照组,差异有统计学意义(P0.05)。研究组的胃半排空时间较对照组延长,差异有统计学意义(P0.05)。结论:口服胃肠超声助显剂可作为临床诊断2型糖尿病患者合并胃轻瘫的一种可靠的可反复的无创伤的检测手段。  相似文献   
992.
目的:探究阴道超声与宫腔镜对诊断子宫内膜病变的临床应用价值。方法:选取我院妇产科收治的子宫内膜病变患者153例,进行阴道超声及宫腔镜检测,观测患者病变类型以及病变部位,比较术后患者临床资料与术前阴道超声以及宫腔镜的检测结果,对阴道超声及宫腔镜的准确率、敏感性、阳性预测率以及阴性预测率等进行比较。结果:阴道超声检测内膜增生漏诊3例、内膜息肉误诊3例、粘膜下肌瘤误诊2例、内膜炎漏诊2例、内膜癌漏诊1例;宫腔镜检测内膜息肉误诊1例、黏膜下肌层误诊2例、内膜炎漏诊1例;与病理活检结果的符合率比较,宫腔镜的总符合率显著高于阴道超声,差异有统计学意义(P0.05)。宫腔镜检测子宫内膜病变的准确率、敏感性、阳性预测率及阴性预测率显著优于阴道超声,差异有统计学意义(P0.05)。结论:阴道超声和宫腔镜均可检测子宫内膜病变,前者操作简单、创伤小,后者操作复杂,但检出率、准确率及敏感度均较高,可减少临床误诊、漏诊的发生率。  相似文献   
993.

Introduction

Survival benefit from ICD implantation is relatively low in primary prevention patients. Better patient selection is important to maintain maximum survival benefit while reducing the number of unnecessary implants. Microvolt T-wave alternans (MTWA) is a promising risk marker. In this study, we aimed to evaluate the predictive value of MTWA in ICD patients.

Methods and results

This study was a substudy of the Twente ICD Cohort Study (TICS). Patients with ischaemic or non-ischaemic left ventricular dysfunction who received an ICD following current ESC guidelines were eligible for inclusion. Exercise-MTWA was performed and classified as non-negative or negative. The primary endpoint was the composite of mortality and appropriate shock therapy. Analysis was performed in 134 patients (81 % male, mean age 62 years, mean ejection fraction 26.5 %). MTWA was non-negative in 64 %. There was no relation between non-negative MTWA testing and mortality and/or appropriate shock therapy (all p-values >0.15). Due to clinical conditions, 24 % were ineligible for testing. These patients experienced the highest risk for mortality (p < 0.01).

Conclusion

Non-negative MTWA testing did not predict mortality and/or appropriate shock therapy. Furthermore, MTWA testing is not feasible in a large percentage of patients. These ineligible patients experience the highest risk for mortality.  相似文献   
994.
Majority of deaths due to communicable and non-communicable diseases occur in the low and middle-income nations (LMNs), mainly due to the lack of early diagnoses and timely treatments. In such a scenario, biomarkers serve as an indispensible resource that can be used as indicators of biological processes, specific disease conditions or response to therapeutic interventions. Evaluation, diagnosis and management of diseases in developing world by following/extrapolating the findings obtained on the basis of the research work involving only the populations from the developed countries, could often be highly misleading due to existence of diverse patterns of diseases in developing countries compared to the developed world. Biomarker candidates identified from high-throughput integrated omics technologies have promising potential; however, their actual clinical applications are found to be limited, primarily due to the challenges of disease heterogeneity and pre-analytical variability associated with the biomarker discovery pipeline. Additionally, in the developing world, economic crunches, lack of awareness and education, paucity of biorepositories, enormous diversities in socio-epidemiological background, ethnicity, lifestyle, diet, exposure to various environmental risk factors and infectious agents, and ethical and social issues also cumulatively hinder biomarker discovery ventures. Establishment of standard operating procedures, comprehensive data repositories and exchange of scientific findings are crucial for reducing the variability and fragmentation of data. This review highlights the challenges associated with the discovery, validation and translational phases of biomarker research in LMNs with some of their amenable solutions and future prospects. This article is part of a Special Issue entitled: Biomarkers: A Proteomic Challenge.  相似文献   
995.
Performing a well thought‐out proteomics data analysis can be a daunting task, especially for newcomers to the field. Even researchers experienced in the proteomics field can find it challenging to follow existing publication guidelines for MS‐based protein identification and characterization in detail. One of the primary goals of bioinformatics is to enable any researcher to interpret the vast amounts of data generated in modern biology, by providing user‐friendly and robust end‐user applications, clear documentation, and corresponding teaching materials. In that spirit, we here present an extensive tutorial for peptide and protein identification, available at http://compomics.com/bioinformatics‐for‐proteomics . The material is completely based on freely available and open‐source tools, and has already been used and refined at numerous international courses over the past 3 years. During this time, it has demonstrated its ability to allow even complete beginners to intuitively conduct advanced bioinformatics workflows, interpret the results, and understand their context. This tutorial is thus aimed at fully empowering users, by removing black boxes in the proteomics informatics pipeline.  相似文献   
996.
作物种质资源品质性状鉴定评价现状与展望   总被引:2,自引:0,他引:2  
作物种质资源品质性状鉴定评价是作物种质资源研究的重要方面,是深入挖掘、广泛利用作物种质资源的基础。本文对近年来作物种质资源品质性状鉴定评价情况进行了回顾,总结了鉴定评价工作取得的主要进展:完成了近20万份的作物种质资源(约占保存总数的50%)主要营养品质性状的初步鉴定评价;作物种质资源品质鉴定评价内容涉及面广、鉴定的品质性状变异性大、多样性丰富;提高了作物种质资源品质性状鉴定评价标准化程度。此外还介绍了国际上有关品质性状鉴定的发展趋势,并对未来国内作物种质资源品质性状鉴定评价提出了意见和建议。  相似文献   
997.

Introduction

Rheumatoid arthritis (RA) patients with structural progression are in most need of immediate treatment to maintain tissue integrity. The serum protein fingerprint, type I collagen degradation mediated by matrix metalloproteinases (MMP)-cleavage (C1M), is a biomarker of tissue destruction. We investigated whether baseline serum C1M levels could identify structural progressors and if the biomarker levels changed during anti-inflammatory treatment with tocilizumab (TCZ).

Methods

The LITHE-biomarker study (NCT00106535, n = 585) was a one-year phase III, double-blind, placebo (PBO)-controlled, parallel group study of TCZ 4 or 8 mg/kg every four weeks, in RA patients on stable doses of methotrexate (MTX). Spearman''s ranked correlation was used to assess the correlation between baseline C1M levels and structural progression at baseline and at weeks 24 and 52. Multivariate regression was performed for delta structural progression. Change in C1M levels were studied as a function of time and treatment.

Results

At baseline, C1M was significantly correlated to C-reactive protein (P <0.0001), visual analog scale pain (P <0.0001), disease activity score28-erythrocyte sedimentation rate (DAS28-ESR) (P <0.0001), joint space narrowing (JSN) (P = 0.0056) and modified total Sharp score (mTSS) (P = 0.0006). Baseline C1M was significantly correlated with delta-JSN at Week 24 (R2 = 0.09, P = 0.0001) and at Week 52 (R2 = 0.27, P <0.0001), and with delta-mTSS at 24 weeks (R2 = 0.006, P = 0.0015) and strongly at 52 weeks (R2 = 0.013, P <0.0001) in the PBO group. C1M levels were dose-dependently reduced in the TCZ + MTX group.

Conclusions

Baseline C1M levels correlated with worsening joint structure over one year. Serum C1M levels may enable identification of those RA patients that are in most need of aggressive treatment

Trial registration

ClinicalTrials.gov: NCT00106535  相似文献   
998.
目的:了解现阶段上海市产科和妇保专业人员对孕产妇常见心理行为问题的识别率及处理方法。方法:共有332例上海市产科和妇保专业人员完成了《孕产妇常见心理行为问题案例分析》。该问卷包括2个案例,第一个为产后抑郁症,第二个为精神分裂症。每个案例后设置了同样的3个相关问题,分别为最可能的诊断、需要补充的资料和最合适的处理。结果:调查对象中91.0%能够正确识别产后抑郁症;多数受访者(81.9%)能够意识到信息不够,需要补充选项所列全部资料,10.8%的受访者只关心孕产期相关因素;18.1%的受访者选择转入精神科专科机构接受住院治疗。调查对象中仅13.9%能够正确识别精神分裂症,高达69.9%的受访者将其误判为产后抑郁症;78.3%认为需要补充选项所列全部资料;有24.7%的受访者认为目前最合适的处理方法是转入精神科专科机构接受住院治疗。医生比护士和助产士对孕产妇常见心理行为问题的识别能力高,二级医院的识别率比三级医院高。结论:上海市产科和妇保专业人员对产后抑郁症的识别率较高,但对精神分裂症的识别率还有待提高,且对孕产妇心理行为问题的处理方式不够恰当。职业类型(医生、护士或助产士)和单位级别为识别率的影响因素。  相似文献   
999.
Abstract

The floristic composition and spatial structure of a West African riverine forest in north-western Benin were studied in order to identify vegetation zones and their arrangement and composition. Data were collected on five continuous belt transects and were analysed using multivariate methods. A total of 133 tree taxa from 34 plant families were identified, with Rubiaceae and Leguminosae-Papilionoideae as the most frequent families. Fifteen homogeneous transect sections were documented. Near-river sections were dominated by water-demanding species (Syzygium guineense, Garcinia ovalifolia, Berlinia grandiflora, Breonardia salicina) (=gallery forest), whereas uphill sections were characterised by savanna species (Terminalia laxiflora, Hymenocardia acida, Detarium microcarpum, Burkea africana) (= savanna). The shift from gallery forest to savanna was reflected by a floristic turnover and the different physiognomy of the vegetation, although diversity values for gallery forest and savanna were very similar. In the Principal Co-ordinates Analysis (PCoA), gallery forest and savanna sections did not overlap. Parallel sections at both sides of the river could be linked by isolines following the topography parallel to the river, resulting in a continuous gallery forest belt (width between 10 and 30 m) flanked by savanna. Tree species typical for gallery forests have wider areas of distribution than savanna species.  相似文献   
1000.
D. W. Goodall 《Plant biosystems》2013,147(6):1346-1354
Using a data base underpinned by probability considerations in which a variety of attributes, some of which may be quantitative, are recorded for a number of “operational taxonomic units” (OTUs), a key system is described by which an unnamed specimen may quickly be identified. The concept of “diagnostic power” is introduced, by which each attribute is evaluated in terms of its potential contribution to identifying the unnamed specimen. Besides coverage of different types of attributes and the introduction of “diagnostic power”, the system has the advantages of incorporating multiple values of an attribute for each OTU and offering short-cuts to identification.  相似文献   
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