全文获取类型
收费全文 | 2763篇 |
免费 | 143篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 51篇 |
妇产科学 | 171篇 |
基础医学 | 467篇 |
口腔科学 | 17篇 |
临床医学 | 264篇 |
内科学 | 419篇 |
皮肤病学 | 18篇 |
神经病学 | 227篇 |
特种医学 | 84篇 |
外科学 | 112篇 |
综合类 | 429篇 |
预防医学 | 261篇 |
眼科学 | 27篇 |
药学 | 232篇 |
中国医学 | 88篇 |
肿瘤学 | 39篇 |
出版年
2024年 | 5篇 |
2023年 | 38篇 |
2022年 | 72篇 |
2021年 | 104篇 |
2020年 | 84篇 |
2019年 | 73篇 |
2018年 | 88篇 |
2017年 | 72篇 |
2016年 | 79篇 |
2015年 | 70篇 |
2014年 | 190篇 |
2013年 | 208篇 |
2012年 | 160篇 |
2011年 | 173篇 |
2010年 | 131篇 |
2009年 | 111篇 |
2008年 | 148篇 |
2007年 | 107篇 |
2006年 | 122篇 |
2005年 | 103篇 |
2004年 | 72篇 |
2003年 | 71篇 |
2002年 | 60篇 |
2001年 | 56篇 |
2000年 | 62篇 |
1999年 | 33篇 |
1998年 | 26篇 |
1997年 | 52篇 |
1996年 | 32篇 |
1995年 | 25篇 |
1994年 | 29篇 |
1993年 | 29篇 |
1992年 | 25篇 |
1991年 | 25篇 |
1990年 | 17篇 |
1989年 | 14篇 |
1988年 | 17篇 |
1987年 | 12篇 |
1986年 | 11篇 |
1985年 | 20篇 |
1984年 | 13篇 |
1983年 | 11篇 |
1982年 | 15篇 |
1981年 | 15篇 |
1980年 | 9篇 |
1979年 | 12篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1976年 | 10篇 |
1974年 | 5篇 |
排序方式: 共有2945条查询结果,搜索用时 15 毫秒
991.
为研究低温潮湿作业对女工月经机能的影响,我们对大连市水产行业从事低温潮湿作业的426名女工月经状况采取整群抽样方法进行了回顾性个案调查.以同行业常温下作业女工及部分勤杂工387名做对照.两组年龄、工龄及月经史、孕育史基本相同.结果表明:低温潮湿作业女工的月经异常发生率明显高于对照组.主要以经期延长、经血量过多,痛经及经前紧张症为主.接触低温潮湿作业工龄越短,月经异常发生率越高.其机理可能是低温潮湿环境刺激使丘脑下部一垂体一卵巢轴相互调节功能发生紊乱所致.随着工龄的增加,可产生一定的适应性.说明月经异常主要为功能性的.提示尤其要注意年轻、接触低温潮湿工龄短的女工的劳动保护. 相似文献
992.
Optical Recording of Neuronal Activity in the Insect Central Nervous System: Odorant Coding by the Antennal Lobes of Honeybees 总被引:1,自引:0,他引:1
Edmund E. Lieke 《The European journal of neuroscience》1993,5(1):49-55
Voltage-sensitive dyes and activity-dependent intrinsic optical signals were used to study the spatio-temporal activity in the antennal lobes of honeybees. The intrinsic signals are somewhat slower than the dye signals but show a 10-fold larger intensity change. These intrinsic signals consist of at least two components—one is wavelength-independent and the other strongly wavelength-dependent, with a maximum at ∼500 nm. Local inhibitory connections within the antennal lobes were examined by recording the activity elicited by an electrical stimulus to the antennal nerve of a slice preparation before and after applying picrotoxin to manipulate GABAergic inhibitory synapses. The inhibition starts with a delay of ∼10 ms after onset of the response and has at least two components. The spatial distribution of the inhibition is extremely inhomogeneous, with areas of small inhibition adjacent to areas of large inhibition. Thus inhibitory interactions in the antennal lobes are not evenly distributed among the glomerular organization. Stimulation of an in vivo preparation with an odour yields a spatially restricted activity. However, the spatial map appears highly dynamic in time because the size of the activated area is a function of the time during and after the stimulus. 相似文献
993.
基于Microsoft Windows98平台的网络睡眠监护系统,利用VTOOLSD开发生理信号采集卡虚拟设备驱动程序(VxD),在VxD中实现IRQ的虚拟化,钩挂中断处理程序,实时处理硬件中断,采集心电、脑电等多路生理信号。这样,可以充分发挥Win98的优势.使得网络睡眠监护系统能够满足家庭保健和社区医疗的需求。 相似文献
994.
M. D. B. Stephens 《Pharmacoepidemiology and drug safety》1994,3(2):91-103
There are many sources of asymptomatic abnormal liver function tests in clinical trials other than hepatotoxicity. It is, therefore, important to identify these sources by looking at the patient's past and present medical history for diseases or activities that may cause these abnormalities, study the degree and duration of the abnormality and the ratio of the different parameters to see whether they are consistent with the hypothesis that the drug is not hepatotoxic and that another cause is more likely. Diseases and activities that can cause these abnormalities are given and methods of analysis outlined. There is no good evidence that abnormal liver function tests are predictive of hepatotoxicity. 相似文献
995.
Computer interpretation of electrocardiograms is far from adequate. This paper highlights a particular type of computer error that is merely symbolic of the large number of errors the computer can make. In addition to computer errors in electrocardiography, it is likely that computer interpretation has diminished the ability of physicians to interpret electrocardiograms. 相似文献
996.
肿瘤相关糖蛋白-72特异性T细胞活化融合基因的分子克隆 总被引:2,自引:2,他引:0
目的:克隆正常人T细胞CD3ζ胞内区、跨膜区基因,将其与肿瘤相关抗原肿瘤相关糖蛋白-72(TAG-71)特异性单链抗体基因克隆入直核表达载体。方法:用逆录-聚合酶链反应(RT-PCR)法从正常人外周血T细胞扩增出CD3ζ胞内区、跨膜区基因;应用PCR法扩增抗TAG-72特异性单链抗体(scFv)基因;将该单链抗体与CD3ζ基因顺序克隆构建重组真核表达载体scFv-CD3ζ-pcDNA3.0并测序。结果:抗TAG-72 scFv cDNA片段为729bp,与已知的序列相符;CD3ζ胞内区、跨膜区的cDNA片段为306bp,与Gene Bank公布的序列一致。重组的表达载体经酶切琼脂糖电泳及测序加以证实。结论:成功构建了含抗肿瘤相关抗原TAG-72scFv及CD3ζ胞内区、跨膜区序列的重组表达载体scFv-CD3ζ-pcDNA3.0,为制备消化道肿瘤靶向性嵌合锚定T细胞奠定了实验基础。 相似文献
997.
目的 了解男性染色体异常核型对优生优育的影响。方法 对123例男性染色体异常核型进行细胞遗传学分析。结果 123例男性中60例(48.7%)为47,XXY,6例(4.9%)为47,xxy/46,xy;7例(5.2%)为大Y染色体;5例(4.5%)为46,xy,del(y)(q11);44例(35.8%)为常染色体异常;1例(0.8%)为46,xx男性综合症。结论 男性染色体异常严重影响人类的生育和婚姻质量,婚前对男性可疑患者进行染色体核型检查是必要的。 相似文献
998.
三地固冲汤治疗节育手术并发子宫异常出血的研究 总被引:1,自引:0,他引:1
本文通过动物实验和临床研究,证明了三地固冲汤对节育手术并发子宫异常出血有较好疗效,并探讨了其作用机理。临床研究表现本药能改善节育手术并发子宫异常出血的临床症状与体征,其临床有效率与对照组比较,两者之间有显著性差异(P<0.01,P<0.05,P<0.05)。动物实验结果表明:(1)三地固冲汤能明显缩短小鼠出、凝血时间。(2)三地固冲汤对具有正常兴奋性的离体大鼠子宫平滑肌具有抑制作用。(3)三地固冲汤对已受抑制的离体子宫平滑肌具有兴奋作用。 相似文献
999.
Joan M. Sullivan 《Journal for specialists in pediatric nursing》1997,2(1):21-28
purpose. To describe a maternal problem-solving process from new mothers' day-to-day experience of caring for and developing a relationship with their babies
design. Qualitative study using grounded theory approach
setting. Mothers' homes (n = 23) and workplaces (n = 2)
participants. 25 mothers of babies from 2 weeks to 7 months
main outcome measures. Semi-structured interviews
results. "Learning the Baby" was a major thinking process that emerged. Systematic thinking dominated mothers' problem-solving. Even after the babies were comforted, mothers were not certain their efforts alleviated the babies' problems, because they usually were not certain of the problem.
conclusions. Mothers' thinking directs their caregiving actions. The findings were related to previous problem-solving and women's thinking perspectives. Nurses must use planned and unplanned encounters effectively to collaborate with and teach mothers about baby behavior and health care. 相似文献
design.
design. Qualitative study using grounded theory approach
setting.
setting. Mothers' homes (n = 23) and workplaces (n = 2)
participants.
participants. 25 mothers of babies from 2 weeks to 7 months
main outcome measures.
main outcome measures. Semi-structured interviews
results.
results. "Learning the Baby" was a major thinking process that emerged. Systematic thinking dominated mothers' problem-solving. Even after the babies were comforted, mothers were not certain their efforts alleviated the babies' problems, because they usually were not certain of the problem.
conclusions.
conclusions. Mothers' thinking directs their caregiving actions. The findings were related to previous problem-solving and women's thinking perspectives. Nurses must use planned and unplanned encounters effectively to collaborate with and teach mothers about baby behavior and health care. 相似文献
1000.