全文获取类型
收费全文 | 930篇 |
免费 | 59篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 16篇 |
妇产科学 | 22篇 |
基础医学 | 116篇 |
口腔科学 | 6篇 |
临床医学 | 122篇 |
内科学 | 137篇 |
皮肤病学 | 40篇 |
神经病学 | 67篇 |
特种医学 | 76篇 |
外科学 | 82篇 |
综合类 | 8篇 |
预防医学 | 121篇 |
眼科学 | 8篇 |
药学 | 64篇 |
中国医学 | 6篇 |
肿瘤学 | 97篇 |
出版年
2023年 | 9篇 |
2022年 | 25篇 |
2021年 | 45篇 |
2020年 | 19篇 |
2019年 | 37篇 |
2018年 | 25篇 |
2017年 | 21篇 |
2016年 | 24篇 |
2015年 | 29篇 |
2014年 | 58篇 |
2013年 | 57篇 |
2012年 | 96篇 |
2011年 | 78篇 |
2010年 | 36篇 |
2009年 | 41篇 |
2008年 | 40篇 |
2007年 | 59篇 |
2006年 | 46篇 |
2005年 | 50篇 |
2004年 | 32篇 |
2003年 | 36篇 |
2002年 | 41篇 |
2001年 | 8篇 |
2000年 | 12篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1964年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有993条查询结果,搜索用时 15 毫秒
1.
C T Brighton E Okereke S R Pollack C C Clark 《Clinical orthopaedics and related research》1992,(285):255-262
Newborn rat calvarial bone cells were grown to confluence and subjected to a matrix of sine wave 60-kHz capacitively coupled electrical signals of various field strengths, pulse-burst patterns, and duty cycles. Both [3H] thymidine incorporation into DNA and alkaline phosphatase activity were evaluated in field strengths ranging from 0.0001 to 20 mV/cm, with pulse-burst patterns ranging from continuous to 5 milliseconds ON/495 milliseconds OFF, with daily duty cycles ranging from 0.25% to 25%. A significant increase in proliferation occurred in field strengths of 0.1, 1, and 20 mV/cm when the signal was applied continuously for six hours. Significant proliferation also occurred when the 20-mV/cm field was pulsed for six hours at 5 milliseconds ON/495 milliseconds OFF and at 5 milliseconds ON/245 milliseconds OFF. No change in alkaline phosphatase activity occurred in the 20-mV/cm field with any signal. At 1 mV/cm, there was a significant decrease in alkaline phosphatase activity in the continuous signal and in the 5 milliseconds ON/62 milliseconds OFF signal; in the lower fields evaluated, there was an actual decrease in alkaline phosphatase activity with some of the signals. The field strength plays a dominant role in determining the bone-cell's proliferative response, and to a lesser extent the alkaline phosphatase activity response, to a capacitively coupled electric field. The pulse configuration and the duty cycle are also important, but only if the proper field strength is being applied to the cell. 相似文献
2.
Because yoga practitioners think they are benefiting from their breath training we hypothesized that yoga respiration training (YRT) could modify the respiratory sensation. Yoga respiration (YR) ("ujjai") consisted of very slow, deep breaths (2-3 min(-1)) with sustained breath-hold after each inspiration and expiration. At inclusion in the study and after a 2-month YRT program, we determined in healthy subjects their eupneic ventilatory pattern and their capacity to discriminate external inspiratory resistive loads (respiratory sensation), digital tactile mechanical pressures (somesthetic sensation) and sound-pressure stimulations (auditory sensation). Data were compared to a gender-, age-, and weight-matched control group of healthy subjects who did not undergo the YRT program but were explored at the same epochs. After the 2-month YRT program, the respiratory sensation increased. Thus, both the exponent of the Steven's power law (Psi=kPhin) and the slope of the linear-linear plot between Psi and mouth pressure (Pm) were significantly higher, and the intercept with ordinate axis of the Psi versus Pm relationship was lower. After YRT, the peak Pm developed against inspiratory loads was significantly lower, reducing the load-induced activation of respiratory afferents. YRT induced long-lasting modifications of the ventilatory pattern with a significant lengthening of expiratory duration and a modest tidal volume increase. No significant changes in somesthetic and auditory sensations were noted. In the control group, the respiratory sensation was not modified during a 15-min period of yoga respiration, despite the peak Pm changes in response to added loads were then significantly reduced. These data suggest that training to yoga respiration selectively increases the respiratory sensation, perhaps through its persistent conditioning of the breathing pattern. 相似文献
3.
4.
5.
Cervical preparation with laminaria reduces complications with 2nd trimester dilation and evacuation. During a surgical abortion at 22 weeks, we could not remove laminaria manually or with ring forceps due to laminaria “dumbbelling” [1]. Without pushing laminaria into the uterus, we mechanically dilated the cervix and removed the incarcerated laminaria. 相似文献
6.
Melody R. Palmer Daniel S. Kim David R. Crosslin Ian B. Stanaway Elisabeth A. Rosenthal David S. Carrell David J. Cronkite Adam Gordon Xiaomeng Du Yatong K. Li Marc S. Williams Chunhua Weng Qiping Feng Rongling Li Sarah A. Pendergrass Hakon Hakonarson David Fasel Sunghwan Sohn Patrick Sleiman Samuel K. Handelman Elizabeth Speliotes Iftikhar J. Kullo Eric B. Larson Gail P. Jarvik 《Genetic epidemiology》2021,45(1):4-15
7.
Melody Okereke Nelson Ashinedu Ukor Yusuff Adebayo Adebisi Isaac Olushola Ogunkola Eseosa Favour Iyagbaye Greatman Adiela Owhor Don Eliseo Lucero‐Prisno 《The International journal of health planning and management》2021,36(1):13-17
The COVID‐19 pandemic continues to be a major public health threat globally and low‐ and middle‐income countries (LMICs) are not an exception. The impact of the COVID‐19 pandemic is far‐reaching on many areas including but not limited to global health security, economic and healthcare delivery with a potential impact on access to healthcare in LMICs. We evaluate the impact of the COVID‐19 pandemic on access to healthcare in LMICs, as well as plausible strategies that can be put in place to ensure that the delivery of healthcare is not halted. In order to mitigate the devastating effect of the COVID‐19 pandemic on the already weak health systems in LMICs, it is much necessary to reinforce and scale up interventions and proactive measures that will ensure that access to healthcare is not disrupted even in course of the pandemic. 相似文献
8.
Reece IJ Painvin GA Chandler LB Gentry BL Zeluff B Okereke OU Cooley DA Frazier OH 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》1984,11(1):32-37
Since July 1982, 18 patients have undergone orthotopic cardiac transplantation at the Texas Heart Institute with steroid and cyclosporine immunosuppression. There have been no deaths from infection despite 15 bacterial, 8 viral, 6 fungal and 1 protozoal infection episodes. With a total follow-up of 90 patient months (mean follow-up, 5.0 months; range 0.1 to 18 months), the incidence of infection is 33 episodes per 100 patient months (1.7 episodes per patient). Only 23 episodes (77%) required drug treatment. Compared to conventional immunosuppressive regimes, cyclosporine treatment is associated with a substantial reduction in the incidence and severity of infection in cardiac allograft recipients. 相似文献
9.
Frequency of the ATM IVS10-6T→G variant in Australian multiple-case breast cancer families 下载免费PDF全文
10.