全文获取类型
收费全文 | 392篇 |
免费 | 40篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 11篇 |
妇产科学 | 5篇 |
基础医学 | 78篇 |
口腔科学 | 4篇 |
临床医学 | 37篇 |
内科学 | 92篇 |
皮肤病学 | 7篇 |
神经病学 | 34篇 |
特种医学 | 63篇 |
外科学 | 28篇 |
综合类 | 5篇 |
预防医学 | 7篇 |
眼科学 | 8篇 |
药学 | 45篇 |
肿瘤学 | 18篇 |
出版年
2023年 | 5篇 |
2021年 | 4篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 6篇 |
2014年 | 9篇 |
2013年 | 13篇 |
2012年 | 6篇 |
2011年 | 15篇 |
2010年 | 11篇 |
2009年 | 15篇 |
2008年 | 14篇 |
2007年 | 24篇 |
2006年 | 14篇 |
2005年 | 11篇 |
2004年 | 10篇 |
2003年 | 10篇 |
2002年 | 6篇 |
2001年 | 10篇 |
2000年 | 8篇 |
1999年 | 8篇 |
1998年 | 18篇 |
1997年 | 12篇 |
1996年 | 9篇 |
1995年 | 11篇 |
1994年 | 13篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 13篇 |
1990年 | 7篇 |
1989年 | 11篇 |
1988年 | 7篇 |
1987年 | 12篇 |
1986年 | 14篇 |
1985年 | 6篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1978年 | 9篇 |
1977年 | 4篇 |
1976年 | 6篇 |
1975年 | 3篇 |
1970年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有443条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Rats with thalamic taste nuclei lesions were adapted to a 23 hr 50 min deprivation schedule and then presented with 0.125 percent saccharin followed by an injection of LiCl or saline. When retested with saccharin, animals with lesions showed a marked attenuation in taste aversion as compared to controls. 相似文献
5.
Anderson RA; Wallace AM; Kicman AT; Wu FC 《Human reproduction (Oxford, England)》1997,12(8):1657-1662
Administration of supraphysiological doses of testosterone to normal men
causes inhibition of spermatogenesis, but while most become azoospermic,
30-55% maintain a low rate of spermatogenesis. We have investigated whether
there are differences in endogenous androgen production, of testicular and
adrenal origin, which may be related to the degree of suppression of
spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m.
injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic,
while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a
specific testicular product, was reduced to <10% of pretreatment values,
with no differences between the groups. Similar results were obtained for
other markers of testicular steroidogenesis. Urinary and plasma adrenal
androgens were also reduced during TE treatment: a statistically
significant decrease in both (P < 0.001 and P < 0.05 respectively)
was seen in the azoospermic but not oligozoospermic responders. These
results suggest that testicular steroidogenesis is decreased to <10% by
the administration of supraphysiological doses of exogenous testosterone.
Differences in the degree of ongoing steroidogenesis in the testis do not
appear to account for incomplete suppression of spermatogenesis, thus
differences in androgen metabolism may underlie this heterogeneous
response. A small but significant reduction in secretion of adrenal
androgens was also detectable, the relevance of which is unclear.
相似文献
6.
Endogenous mouse mammary tumor virus DNA is distributed among multiple mouse chromosomes. 总被引:11,自引:0,他引:11
We have examined the distribution of endogenous mouse mammary tumor virus-specific DNA in the genome of A/HeJ mice by using molecular hybridization and restriction endonucleases to analyze DNA from mouse-hamster hybrid clones that segregate mouse chromosomes. We have found that MMTV sequences are located on at least three separate chromosomal pairs, including chromosome number four. 相似文献
7.
Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells. 相似文献
8.
Molecular cloning of several primary or passaged RadLV variants and their biological characterization has allowed us to propose a model of their emergence following X-ray irradiation of C57BL/6 mouse. 相似文献
9.
Judith K. Ockene Rashelle B. Hayes Linda C. Churchill Sybil L. Crawford Denise G. Jolicoeur David M. Murray Abigail B. Shoben Sean P. David Kristi J. Ferguson Kathryn N. Huggett Michael Adams Catherine A. Okuliar Robin L. Gross Pat F. BassIII Ruth B. Greenberg Frank T. Leone Kola S. Okuyemi David W. Rudy Jonathan B. Waugh Alan C. Geller 《Journal of general internal medicine》2016,31(2):172-181
Background
Early in medical education, physicians must develop competencies needed for tobacco dependence treatment.Objective
To assess the effect of a multi-modal tobacco dependence treatment curriculum on medical students’ counseling skills.Design
A group-randomized controlled trial (2010–2014) included ten U.S. medical schools that were randomized to receive either multi-modal tobacco treatment education (MME) or traditional tobacco treatment education (TE).Setting/Participants
Students from the classes of 2012 and 2014 at ten medical schools participated. Students from the class of 2012 (N?=?1345) completed objective structured clinical examinations (OSCEs), and 50 % (N?=?660) were randomly selected for pre-intervention evaluation. A total of 72.9 % of eligible students (N?=?1096) from the class of 2014 completed an OSCE and 69.7 % (N?=?1047) completed pre and post surveys.Interventions
The MME included a Web-based course, a role-play classroom demonstration, and a clerkship booster session. Clerkship preceptors in MME schools participated in an academic detailing module and were encouraged to be role models for third-year students.Measurements
The primary outcome was student tobacco treatment skills using the 5As measured by an objective structured clinical examination (OSCE) scored on a 33-item behavior checklist. Secondary outcomes were student self-reported skills for performing 5As and pharmacotherapy counseling.Results
Although the difference was not statistically significant, MME students completed more tobacco counseling behaviors on the OSCE checklist (mean 8.7 [SE 0.6] vs. mean?8.0 [SE 0.6], p?=?0.52) than TE students. Several of the individual Assist and Arrange items were significantly more likely to have been completed by MME students, including suggesting behavioral strategies (11.8 % vs. 4.5 %, p?<?0.001) and providing information regarding quitline (21.0 % vs. 3.8 %, p?<?0.001). MME students reported higher self-efficacy for Assist, Arrange, and Pharmacotherapy counseling items (ps?≤0.05).Limitations
Inclusion of only ten schools limits generalizability.Conclusions
Subsequent interventions should incorporate lessons learned from this first randomized controlled trial of a multi-modal longitudinal tobacco treatment curriculum in multiple U.S. medical schools.NIH Trial Registry Number: NCT0190561810.
Chiang Jannifer O. Azevedo Rafael S. Justino Maria C. A. Matos Haroldo J. Cabeça Hideraldo L. S. Silva Sandro P. Henriques Daniele F. Silva Eliana V. P. Andrade Gabriela S. S. Vasconcelos Pedro FC. Martins Lívia C. Azevedo Raimunda S. S. 《Journal of neurovirology》2021,27(4):626-630
Journal of NeuroVirology - We describe two neurological cases of Oropouche virus infection in northern Brazil, where the virus is endemic but neglected as a pathogen. This study reiterates the... 相似文献