首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   190篇
  免费   4篇
  国内免费   4篇
儿科学   13篇
妇产科学   2篇
基础医学   23篇
口腔科学   7篇
临床医学   14篇
内科学   35篇
皮肤病学   2篇
神经病学   4篇
特种医学   51篇
外科学   6篇
综合类   8篇
预防医学   8篇
眼科学   3篇
药学   20篇
肿瘤学   2篇
  2022年   1篇
  2021年   5篇
  2019年   4篇
  2018年   1篇
  2017年   1篇
  2016年   3篇
  2015年   4篇
  2014年   9篇
  2013年   6篇
  2012年   1篇
  2011年   1篇
  2010年   6篇
  2009年   3篇
  2008年   3篇
  2007年   4篇
  2006年   3篇
  2005年   9篇
  2004年   4篇
  2003年   3篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1999年   5篇
  1998年   14篇
  1997年   13篇
  1996年   16篇
  1995年   8篇
  1994年   8篇
  1993年   15篇
  1992年   3篇
  1991年   2篇
  1990年   3篇
  1989年   9篇
  1988年   5篇
  1987年   3篇
  1986年   2篇
  1985年   3篇
  1984年   2篇
  1983年   3篇
  1981年   1篇
  1980年   2篇
  1979年   1篇
  1977年   2篇
  1976年   2篇
排序方式: 共有198条查询结果,搜索用时 13 毫秒
11.
12.

Background

By 2025, it is estimated that approximately 1.8 million Australian adults (approximately 8.4% of the adult population) will have diabetes, with the majority having type 2 diabetes. Weight management via improved physical activity and diet is the cornerstone of type 2 diabetes management. However, the majority of weight loss trials in diabetes have evaluated short-term, intensive clinic-based interventions that, while producing short-term outcomes, have failed to address issues of maintenance and broad population reach. Telephone-delivered interventions have the potential to address these gaps.

Methods/Design

Using a two-arm randomised controlled design, this study will evaluate an 18-month, telephone-delivered, behavioural weight loss intervention focussing on physical activity, diet and behavioural therapy, versus usual care, with follow-up at 24 months. Three-hundred adult participants, aged 20-75 years, with type 2 diabetes, will be recruited from 10 general practices via electronic medical records search. The Social-Cognitive Theory driven intervention involves a six-month intensive phase (4 weekly calls and 11 fortnightly calls) and a 12-month maintenance phase (one call per month). Primary outcomes, assessed at 6, 18 and 24 months, are: weight loss, physical activity, and glycaemic control (HbA1c), with weight loss and physical activity also measured at 12 months. Incremental cost-effectiveness will also be examined. Study recruitment began in February 2009, with final data collection expected by February 2013.

Discussion

This is the first study to evaluate the telephone as the primary method of delivering a behavioural weight loss intervention in type 2 diabetes. The evaluation of maintenance outcomes (6 months following the end of intervention), the use of accelerometers to objectively measure physical activity, and the inclusion of a cost-effectiveness analysis will advance the science of broad reach approaches to weight control and health behaviour change, and will build the evidence base needed to advocate for the translation of this work into population health practice.

Trial Registration

ACTRN12608000203358  相似文献   
13.

Objective

To estimate the global cost of establishing and operating the educational and refractive care facilities required to provide care to all individuals who currently have vision impairment resulting from uncorrected refractive error (URE).

Methods

The global cost of correcting URE was estimated using data on the population, the prevalence of URE and the number of existing refractive care practitioners in individual countries, the cost of establishing and operating educational programmes for practitioners and the cost of establishing and operating refractive care facilities. The assumptions made ensured that costs were not underestimated and an upper limit to the costs was derived using the most expensive extreme for each assumption.

Findings

There were an estimated 158 million cases of distance vision impairment and 544 million cases of near vision impairment caused by URE worldwide in 2007. Approximately 47 000 additional full-time functional clinical refractionists and 18 000 ophthalmic dispensers would be required to provide refractive care services for these individuals. The global cost of educating the additional personnel and of establishing, maintaining and operating the refractive care facilities needed was estimated to be around 20 000 million United States dollars (US$) and the upper-limit cost was US$ 28 000 million. The estimated loss in global gross domestic product due to distance vision impairment caused by URE was US$ 202 000 million annually.

Conclusion

The cost of establishing and operating the educational and refractive care facilities required to deal with vision impairment resulting from URE was a small proportion of the global loss in productivity associated with that vision impairment.  相似文献   
14.
15.
Objective: To identify independent predictors of successful labor induction with oral or vaginal misoprostol.

Methods: Women enrolled in four previous randomized trials involving oral or vaginal misoprostol for cervical ripening and labor induction were included in the present cohort study, with dosing of 25–50?μg every 4 to 6?h vaginally (n?=?574) or 50?μg every 4?h orally (n?=?207). Multiple logistic regression was performed to identify factors independently associated with successful labor induction – defined as vaginal delivery within 12?h, vaginal delivery within 24?h and spontaneous vaginal delivery. Predictors of Cesarean birth and the need for only one dose of misoprostol were also identified. Variables included in the models were maternal age, weight, height, parity, gravidity, membrane status, route of misoprostol, gestational age, birth weight, and Bishop score and its individual components.

Results: Maternal age, height, weight, parity, birth weight, dilatation, effacement and cervical station were associated with vaginal delivery within 24?h of induction. Maternal age, height, weight, nulliparity, birth weight and route of misoprostol were associated with Cesarean birth, with oral misoprostol being associated with a lower rate of Cesarean birth. The need for only one dose of misoprostol was predicted by maternal height, weight, parity, gestational age, Bishop score and route of misoprostol.

Conclusion: Characteristics of the woman (height, weight, parity), the fetus (birth weight) and some of the individual components of the Bishop score, were associated with successful labor induction, with oral misoprostol being associated with a lower rate of Cesarean birth.  相似文献   
16.
目的:综述人脂肪组织来源干细胞的生物学特性及其在缺血性心脏病中的应用,分析不足,并在此基础上提出未来研究要解决的问题,以期为临床治疗提供依据。资料来源:应用计算机检索Blackwell、Elsevier、Pubmed数据库1980/2007期间脂肪源性干细胞与缺血性心脏病方面的文献,检索词为“bone mesenchymal stem cells,adipose derived stemcells,cardiomyocytes,ischemic heart disease”等。应用计算机检索中国期刊全文数据库1980/2007期间相关文献,检索词为“骨髓间充质干细胞,脂肪组织来源的干细胞,心肌细胞,缺血性心脏病”等。并手工查阅相关书籍。资料选择:对资料进行初步选择:①脂肪组织来源干细胞的生物学特性。②脂肪组织来源干细胞治疗缺血性心脏病。排除重复文献。资料提炼:共搜集到相关文章57篇,删除内容重复及与本文主题关系较远的文章,剩余41篇作为综述参考。资料综合:脂肪组织来源干细胞与同样起源于中胚层的骨髓基质细胞不仅具有非常相似的生物学特性,而且在细胞表面标志谱的表达方面也非常相近。并且脂肪组织来源广泛,取材方便,可获得的基质细胞数量大,易于培养扩增。有研究发现,脂肪组织来源干细胞体外培养不需要任何诱导便能分化成具有自律性的心肌细胞,使得脂肪组织来源干细胞治疗缺血性心脏病成为可能。结论:脂肪组织来源干细胞在取材和增殖方面较骨髓间充质干细胞有优势;脂肪组织来源干细胞能较好的诱导为心肌细胞,将为缺血性心脏病的治疗提供更广阔的前景。  相似文献   
17.
目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。 方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。 结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。 结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。  相似文献   
18.
很久以来都认为遗传成分参与2型糖尿病(T2DM)的发病,但是有关遗传学上的发现一直进展缓慢,这是由于遗传成分的复杂性。有关糖尿病相关的各种表型的研究的大量资料提示,所谓的“T2DM”可能是许多疾病的统称,由于它们具有通常相互重叠的多种基本发病机制。因此,对曾抱有期望的T2DM的遗传学基础的寻求已经证明是很艰难的。  相似文献   
19.
Vecchini  F; Patrene  KD; Boggs  SS 《Blood》1993,81(6):1489-1496
Mouse bone marrow (BM) was separated into low-density, lineage- negative, wheat germ agglutinin-positive (WGA+), Rhodamine-123 bright (Rhbright) or dim (Rhdim) cells to obtain populations that were highly enriched for committed progenitors (Rhbright cells) or for more primitive stem cells (Rhdim). When 2,500 Rhbright or Rhdim cells were seeded onto 6-week-old irradiated (20 Gy) long-term BM cultures (LTBMC), the nonadherent cell production from Rhbright cells was transient and ended after 5 weeks. Production from Rhdim cells did not begin until week 3, peaked at week 5, and ended at week 8, when the irradiated stroma seemed to fail. Termination of cell production from Rhdim cells did not occur in nonirradiated LTBMC from W41/Wv mice. During peak nonadherent cell production, 25% to 30% of the cells in the nonirradiated LTBMC from W41/Wv mice had donor cell markers. Two approaches were tested to try to enhance the proportion or number of donor cells. Addition of Origen-HGF at the time of seeding Rhdim cells caused a nonspecific increase in both host and donor cell production, but a specific increase in production of donor cells was obtained by seeding the cultures at 2 weeks rather than 6 weeks. Limiting dilution of Rhdim cells gave the same frequency of wells producing cells on both irradiated +/+ and nonirradiated W41/Wv or W/Wv cultures.  相似文献   
20.
Binding of mammalian spermatozoa to the zona pellucida and the induction of the acrosome reaction are prerequisites for successful oocyte fertilization. It has been postulated that xenobiotics that are released in the environment as well as exposure to pharmaceutical medications may be associated with reproductive problems in men and wildlife. Examining physiological and non-physiological effects of particular compounds on sperm functions requires high quality in-vitro test systems. We established a reliable combined in-vitro test system with bovine gametes and evaluated if aliquots of pooled post-thaw spermatozoa are suitable for examining essential sperm functions. Using cryopreserved semen, the PSA-FITC/Hoechst 33258 staining procedure was applicable to evaluate the acrosomal status and cell viability. In the bovine hemizona assay, hemizona indices revealed no differences between cryopreserved and fresh semen. Treatment of post-thaw bovine spermatozoa with progesterone (1 microM or bovine follicular fluid (20%) induced the acrosome reaction from 12% (untreated spermatozoa) to 25% (P < 0.001) and to 22% [corrected] (P < 0.01), respectively. Incubation of both compounds (1 microM progesterone and 20% follicular fluid) raised the percentage of acrosome-reacted spermatozoa to 30% (P < 0001). Our results demonstrate that cryopreserved semen can be integrated into an in-vitro screening model for reproductive toxicology testing. Pooled, cryopreserved bovine spermatozoa will thus permit reproducible experiments for clinical and basic science purposes and may also be applicable for the human system.   相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号