全文获取类型
收费全文 | 4831篇 |
免费 | 406篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 38篇 |
儿科学 | 152篇 |
妇产科学 | 89篇 |
基础医学 | 658篇 |
口腔科学 | 193篇 |
临床医学 | 531篇 |
内科学 | 854篇 |
皮肤病学 | 76篇 |
神经病学 | 264篇 |
特种医学 | 362篇 |
外科学 | 633篇 |
综合类 | 111篇 |
一般理论 | 3篇 |
预防医学 | 398篇 |
眼科学 | 37篇 |
药学 | 273篇 |
1篇 | |
中国医学 | 10篇 |
肿瘤学 | 563篇 |
出版年
2021年 | 65篇 |
2020年 | 48篇 |
2019年 | 66篇 |
2018年 | 81篇 |
2017年 | 62篇 |
2016年 | 44篇 |
2015年 | 68篇 |
2014年 | 93篇 |
2013年 | 155篇 |
2012年 | 198篇 |
2011年 | 192篇 |
2010年 | 120篇 |
2009年 | 100篇 |
2008年 | 168篇 |
2007年 | 169篇 |
2006年 | 185篇 |
2005年 | 171篇 |
2004年 | 158篇 |
2003年 | 142篇 |
2002年 | 150篇 |
2001年 | 127篇 |
2000年 | 144篇 |
1999年 | 140篇 |
1998年 | 100篇 |
1997年 | 88篇 |
1996年 | 77篇 |
1995年 | 90篇 |
1994年 | 77篇 |
1993年 | 82篇 |
1992年 | 94篇 |
1991年 | 106篇 |
1990年 | 109篇 |
1989年 | 132篇 |
1988年 | 112篇 |
1987年 | 101篇 |
1986年 | 119篇 |
1985年 | 87篇 |
1984年 | 69篇 |
1983年 | 58篇 |
1982年 | 41篇 |
1981年 | 56篇 |
1980年 | 54篇 |
1979年 | 62篇 |
1978年 | 52篇 |
1976年 | 50篇 |
1975年 | 38篇 |
1973年 | 57篇 |
1972年 | 43篇 |
1971年 | 40篇 |
1967年 | 37篇 |
排序方式: 共有5246条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
Peter J. Morgan Lynda M. Williams Gary Davidson Wilfred Lawson Edward Howell 《Journal of neuroendocrinology》1989,1(1):1-4
The functional significance of the pars tuberalis (PT) of the mammalian adenohypophysis has remained an enigma (1, 2). One view of its function is that it acts as an auxiliary gland to support the endocrine role of the pars distalis (PD) (2), as it has been shown to contain immunocytochemically identifiable thyrotrophs and gonadotrophs (1). Many of the cells of the PT are, however, ultrastructurally unique suggesting an independent function for this tissue. Our recent demonstration that the PT of the rat is a major binding site for the ligand iodomelatonin lends further support to this idea (3). We have utilized the highly specific ligand [125 l]melatonin, and have demonstrated that it binds exclusively, with very high affinity, to the PT but not the PD of the adult sheep adenohypophysis. These findings support the conclusion that the PT has a distinct role in relation to melatonin action and seasonal reproduction. 相似文献
5.
6.
Respiratory symptoms and bronchial reactivity: identification of a syndrome and its relation to asthma 总被引:17,自引:0,他引:17
A K Mortagy J B Howell W E Waters 《British medical journal (Clinical research ed.)》1986,293(6546):525-529
Two postal questionnaire surveys were carried out among the adult population of Southampton aimed at clarifying the diagnostic criteria for asthma (study 1) and at testing the validity of symptoms so identified as diagnostic of bronchial hyper-reactivity (study 2). The questionnaires asked about respiratory symptoms and included three questions thought likely to disclose increased bronchial reactivity. Laboratory measurements on subsamples of respondents included spirometry and bronchial challenge with increasing doses of histamine till a concentration was reached provoking a fall of more than 20% (PC greater than 20) in forced expiratory volume in one second. In the first study no normal subject (that is, one who did not report shortness of breath or wheezing on the questionnaire) had a PC greater than 20 below 0.5 g/l. Of 51 subjects who reported shortness of breath or wheezing, or both, nine had a cluster of abnormalities consisting of one or more symptoms of bronchial irritability, nocturnal dyspnoea, and prolonged morning tightness together with PC greater than 20 values of 0.5 g/l or less. These symptoms in conjunction with a low PC greater than 20 were termed the bronchial irritability syndrome. In the second study bronchial challenge confirmed the close association of these symptoms with bronchial hyper-reactivity, all other subjects being less reactive to histamine. Only 27% of subjects with symptoms of the bronchial irritability syndrome had been diagnosed as asthmatic by their general practitioners. The bronchial irritability syndrome is a definable entity for epidemiological study and patient care. 相似文献
7.
Pharmacological interactions between serotonin and dopamine on behavior in the squirrel monkey 总被引:2,自引:1,他引:1
The behavioral effects of GBR 12909, a selective dopamine uptake inhibitor, were determined in squirrel monkeys trained to
respond under a fixed-interval (FI) schedule of stimulus termination and a second-order schedule of IV drug self-administration.
Intermediate doses of GBR 12909 increased FI response rate markedly, and the highest dose decreased response rate below control
values. The 5HT uptake inhibitors, alaproclate and fluoxetine, and the 5HT agonist, quipazine, attenuated the behavioral-stimulant
effects of GBR 12909, whereas the 5HT2A/2C antagonist, ritanserin, enhanced the behavioral-stimulant effects of the lowest dose. GBR 12909 reliably maintained self-administration,
and ritanserin increased response rate maintained by the highest dose. The dopamine agonist, quinpirole, increased FI response
rate in only one of three subjects, and ritanserin enhanced the behavioral-stimulant effects of quinpirole in that subject.
The dopamine agonist, apomorphine, only decreased FI response rate, and ritanserin did not alter its behavioral effects. The
pharmacological profile of GBR 12909 administered alone and in combination with selective 5HT drugs in the present study was
similar to that obtained previously with cocaine, further demonstrating that 5HT can reliably modulate the behavioral effects
of psychomotor stimulants with prominent dopaminergic actions.
Received: 9 July 1996 / Final version: 22 November 1996 相似文献
8.
A D Deitch V A Andreotti M A Strand L Howell R W deVere White 《The Journal of urology》1990,143(4):700-705
We describe a method to fix exfoliated bladder cells that is suitable for followup of bladder cancer patients by deoxyribonucleic acid flow cytometry. After fixation with room temperature methanol plus acetic acid (20:1, volume:volume) urine and bladder washing samples from these patients can be stored at room temperature for 3 to 7 days and then assessed reliably for the presence of aneuploidy and the percentage of hyperdiploid cells. For those with active transitional cell carcinoma diagnostic accuracy comparing fresh to fixed specimens was improved from 58 to 92% with urine and from 50 to 100% with washing samples. For patients with a history of transitional cell carcinoma who currently are free of disease the false positive rate remains unchanged after fixation. The procedure described is suitable for use in the outpatient clinic and should permit shipping of samples without refrigeration to a central flow cytometry facility for analysis. 相似文献
9.
10.
Toward a VA women’s health research agenda: Setting evidence-based priorities to improve the health and health care of women veterans 下载免费PDF全文
Elizabeth M. Yano Lori A. Bastian Susan M. Frayne Alexandra L. Howell Linda R. Lipson Geraldine McGlynn Paula P. Schnurr Margaret R. Seaver Ann M. Spungen Stephan D. Fihn 《Journal of general internal medicine》2006,21(3):S93-S101
The expansion of women in the military is reshaping the veteran population, with women now constituting the fastest growing segment of eligible VA health care users. In recognition of the changing demographics and special health care needs of women, the VA Office of Research & Development recently sponsored the first national VA Women’s Health Research Agenda-setting conference to map research priorities to the needs of women veterans and position VA as a national leader in Women’s Health Research. This paper summarizes the process and outcomes of this effort, outlining VA’s research priorities for biomedical, clinical, rehabilitation, and health services research. 相似文献