全文获取类型
收费全文 | 798篇 |
免费 | 69篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 1篇 |
妇产科学 | 1篇 |
基础医学 | 119篇 |
口腔科学 | 4篇 |
临床医学 | 55篇 |
内科学 | 58篇 |
皮肤病学 | 4篇 |
神经病学 | 21篇 |
特种医学 | 63篇 |
外科学 | 43篇 |
综合类 | 100篇 |
预防医学 | 122篇 |
眼科学 | 2篇 |
药学 | 194篇 |
中国医学 | 43篇 |
肿瘤学 | 57篇 |
出版年
2024年 | 2篇 |
2023年 | 14篇 |
2022年 | 29篇 |
2021年 | 28篇 |
2020年 | 38篇 |
2019年 | 26篇 |
2018年 | 34篇 |
2017年 | 25篇 |
2016年 | 23篇 |
2015年 | 32篇 |
2014年 | 69篇 |
2013年 | 71篇 |
2012年 | 50篇 |
2011年 | 62篇 |
2010年 | 62篇 |
2009年 | 31篇 |
2008年 | 48篇 |
2007年 | 42篇 |
2006年 | 32篇 |
2005年 | 17篇 |
2004年 | 15篇 |
2003年 | 20篇 |
2002年 | 14篇 |
2001年 | 7篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 10篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 7篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1976年 | 2篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有888条查询结果,搜索用时 15 毫秒
51.
目的:研究出绞股蓝提取物,为绞股蓝产品研发提供实验数据。方法:建立绞股蓝提取物的化学评价方法;优化绞股蓝提取物的提取工艺,用化学评价方法分别对绞股蓝的乙醇浓度、料液比、提取时间、提取次数4个单因素进行考察,以L 9(34)正交表设计优化工艺,筛选出最佳提取工艺。结果:经单因素考察和正交优化得到绞股蓝提取物制备工艺为料液比为1∶8的70%乙醇,加热回流提取3次,每次45 min,绞股蓝总皂苷含量为0.1025 mg/mL,提取率为10.25%。结论:建立的化学评价方法可评价绞股蓝提取物;制备工艺能为绞股蓝产品研发提供依据。 相似文献
52.
53.
54.
Rationale and design of the AdaptResponse trial: a prospective randomized study of cardiac resynchronization therapy with preferential adaptive left ventricular‐only pacing
下载免费PDF全文
![点击此处可从《European journal of heart failure》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Gerasimos Filippatos David Birnie Michael R. Gold Bart Gerritse Ahmad Hersi Sandra Jacobs Kengo Kusano Christophe Leclercq Wilfried Mullens Bruce L. Wilkoff 《European journal of heart failure》2017,19(7):950-957
The AdaptResponse trial is designed to test the hypothesis that preferential adaptive left ventricular‐only pacing with the AdaptivCRT® algorithm reduces the incidence of the combined endpoint of all‐cause mortality and intervention for heart failure (HF) decompensation, compared with conventional cardiac resynchronization therapy (CRT), among patients with a CRT indication, left bundle branch block (LBBB) and normal atrioventricular (AV) conduction. The AdaptResponse study is a prospective, randomized, controlled, single‐blinded, multicentre, clinical trial ( ClinicalTrials.gov Identifier: NCT02205359), conducted at up to 200 centres worldwide. Following enrolment and baseline assessment, eligible subjects will be implanted with a CRT system containing the AdaptivCRT algorithm, and randomized in a 1:1 fashion to either a treatment (‘AdaptivCRT’) or control (‘Conventional CRT’) group. The study is designed to observe a primary endpoint in 1100 patients (‘event‐driven’) and approximately 3000 patients will be randomized. The primary endpoint is the composite of all‐cause mortality and intervention for HF decompensation; secondary endpoints include all‐cause mortality, intervention for HF decompensation, clinical composite score (CCS) at 6 months, atrial fibrillation, quality of life measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ), health outcome measured by the EQ‐5D instrument, all‐cause readmission after a HF admission, and cost‐effectiveness. The AdaptResponse clinical trial is powered to assess clinical endpoints and is expected to provide definitive evidence on the incremental utility of AdaptivCRT‐enhanced CRT systems. 相似文献
55.
目的探索怎样的移植管-宿主动脉直径比和缝合角可以最大限度地提高冠状动脉搭桥术的成功率。方法借助ANSYS9.0对冠状动脉搭桥术进行模拟仿真,用响应面方法建立数学模型,利用优化理论寻找最优的移植管-宿主动脉直径比和缝合角,使影响手术成功率的主要因素-壁面切应力梯度最小。结果结果表明冠状动脉搭桥术中,大移植管-宿主动脉直径比和小缝合角的模型具有更好的血流动力特性。结论影响冠状动脉搭桥术成功率的因素很多,在现有条件下借助临床经验指导,选择尽可能大的移植管-宿主动脉直径比和尽可能小的缝合角的做法是可取的。 相似文献
56.
Kum O 《Medical & biological engineering & computing》2007,45(11):1053-1063
Customized cancer radiation treatment planning for each patient is very useful for both a patient and a doctor because it
provides the ability to deliver higher doses to a more accurately defined tumor and at the same time lower doses to organs
at risk and normal tissues. This can be realized by building an accurate planning simulation system to provide better treatment
strategies based on each patient’s tomographic data such as CT, MRI, PET, or SPECT. In this study, we develop a real-time
online client–server/client collaborative environment between the client (health care professionals or hospitals) and the
server/client under a secure network using telematics (the integrated use of telecommunications and medical informatics).
The implementation is based on a point-to-point communication scheme between client and server/client following the WYSIWIS
(what you see is what I see) paradigm. After uploading the patient tomographic data, the client is able to collaborate with
the server/client for treatment planning. Consequently, the level of health care services can be improved, specifically for
small radiotherapy clinics in rural/remote-country areas that do not possess much experience or equipment such as a treatment
planning simulator. The telematics service of the system can also be used to provide continued medical education in radiotherapy.
Moreover, the system is easy to use. A client can use the system if s/he is familiar with the WindowsTM operating system because it is designed and built based on a user-friendly concept. This system does not require the client
to continue hardware and software maintenance and updates. These are performed automatically by the server. 相似文献
57.
实时逆转录-聚合酶链反应绝对定量实验优化的研究 总被引:13,自引:0,他引:13
目的 探讨优化实验反应条件 ,使实时逆转录 聚合酶链反应 (RT PCR)绝对定量能获得准确可靠的结果。方法 建立质粒标准品作为外参照 ;以管家基因GAPDH作为内参照 ,并对Mg2 、引物与探针比例、Buffer等进行优化。结果 优化条件后 ,RT PCR反应的扩增效率接近了理论最佳值 ,并可使靶基因与管家基因扩增效率保持一致 ,保证了方法的稳定性和可靠性。结论 为了获得可靠、重复性好的实时RT PCR绝对定量结果 ,应对实验方法进行优化。 相似文献
58.
超声引导瘤内注射型卡铂-PLGA缓释微球制备工艺优化研究 总被引:2,自引:2,他引:2
目的探讨制备条件对微球粒径、表面形态和载药量的影响因素,确定制备超声引导瘤内注射型卡铂-PIGA缓释微球的最佳工艺条件。方法以O/O型乳化溶剂挥发法制备微球,采用单因素试验和拟水平均匀设计法优化制备工艺。结果制备微球的最佳条件是卡铂晶体粒径1~4μm,CBP/PIGA投料比为1:7,PLGA浓度为10%,内,外相体积比为1:8,span-80浓度为8%,搅拌速度为1400r/min,乳化和挥发时间分别是15min和4h;此条件所制备微球呈规则球形、表面光滑,粒径100—200μm的微球产出率达到65.4%,载药量为11.6%。结论优化卡铂-PLGA缓释微球的制备条件,可制备出符合瘤内注射要求的缓释微球。 相似文献
59.
Segmentation of carotid artery intima-media in longitudinal ultrasound images for measuring its thickness to predict cardiovascular diseases can be simplified as detecting two nearly parallel boundaries within a certain distance range, when plaque with irregular shapes is not considered. In this paper, we improve the implementation of two dynamic programming (DP) based approaches to parallel boundary detection, dual dynamic programming (DDP) and piecewise linear dual dynamic programming (PL-DDP). Then, a novel DP based approach, dual line detection (DLD), which translates the original 2-D curve position to a 4-D parameter space representing two line segments in a local image segment, is proposed to solve the problem while maintaining efficiency and rotation invariance. To apply the DLD to ultrasound intima-media segmentation, it is imbedded in a framework that employs an edge map obtained from multiplication of the responses of two edge detectors with different scales and a coupled snake model that simultaneously deforms the two contours for maintaining parallelism. The experimental results on synthetic images and carotid arteries of clinical ultrasound images indicate improved performance of the proposed DLD compared to DDP and PL-DDP, with respect to accuracy and efficiency. 相似文献
60.
《Heart rhythm》2021,18(9):1577-1585
- Download : Download high-res image (150KB)
- Download : Download full-size image