全文获取类型
收费全文 | 7520篇 |
免费 | 484篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 55篇 |
儿科学 | 122篇 |
妇产科学 | 124篇 |
基础医学 | 1119篇 |
口腔科学 | 92篇 |
临床医学 | 669篇 |
内科学 | 1550篇 |
皮肤病学 | 127篇 |
神经病学 | 1094篇 |
特种医学 | 574篇 |
外科学 | 907篇 |
综合类 | 79篇 |
一般理论 | 1篇 |
预防医学 | 477篇 |
眼科学 | 252篇 |
药学 | 425篇 |
中国医学 | 6篇 |
肿瘤学 | 357篇 |
出版年
2023年 | 68篇 |
2022年 | 91篇 |
2021年 | 184篇 |
2020年 | 101篇 |
2019年 | 136篇 |
2018年 | 150篇 |
2017年 | 139篇 |
2016年 | 178篇 |
2015年 | 177篇 |
2014年 | 242篇 |
2013年 | 295篇 |
2012年 | 499篇 |
2011年 | 483篇 |
2010年 | 291篇 |
2009年 | 236篇 |
2008年 | 431篇 |
2007年 | 433篇 |
2006年 | 401篇 |
2005年 | 386篇 |
2004年 | 366篇 |
2003年 | 307篇 |
2002年 | 331篇 |
2001年 | 161篇 |
2000年 | 144篇 |
1999年 | 147篇 |
1998年 | 97篇 |
1997年 | 82篇 |
1996年 | 59篇 |
1995年 | 43篇 |
1994年 | 43篇 |
1993年 | 44篇 |
1992年 | 92篇 |
1991年 | 94篇 |
1990年 | 86篇 |
1989年 | 79篇 |
1988年 | 67篇 |
1987年 | 57篇 |
1986年 | 58篇 |
1985年 | 66篇 |
1984年 | 50篇 |
1983年 | 38篇 |
1982年 | 32篇 |
1981年 | 21篇 |
1979年 | 43篇 |
1978年 | 26篇 |
1977年 | 20篇 |
1976年 | 19篇 |
1974年 | 20篇 |
1971年 | 20篇 |
1969年 | 22篇 |
排序方式: 共有8030条查询结果,搜索用时 15 毫秒
1.
Interneurons immunoreactive for vasoactive intestinal polypeptide (VIP) are integral elements of columnar organization patterns in the rat cerebral cortex. By application of the sensitive mirror technique, the co-localization of VIP with the classical inhibitory neurotransmitter γ-aminobutyric acid (GABA) and the acetylcholine-synthesizing enzyme, choline acetyltransferase (ChAT), was investigated in neocortical neurons. Furthermore, the frequency of co-localization of ChAT with GABA was determined. In a sample of 118 VIP-immunoreactive neurons, mostly from the primary somatosensory cortex, it was demonstrated that virtually all of them reveal immunoreactivity for GABA and, therefore, are to be GABAergic. Moreover, 34% of mostly bipolar, VIP-positive neurons contained ChAT and are, thus, supposedly cholinergic as well. Co-localization of VIP and ChAT varied according to cortical laminae. Finally, 88% of a total of 60 ChAT-immunoreactive neurons were also immunostained for GABA. It is concluded that almost all VIP-immunoreactive neurons and most of the cholinergic neurons in rat neocortex represent partly overlapping subpopulations of inhibitory interneurons utilizing GABA. 相似文献
2.
Dr. C. S. Freund 《European archives of psychiatry and clinical neuroscience》1889,20(2):371-416
Ohne ZusammenfassungSchluss aus Bd. XX. Heft 1.Zum Schlusse danke ich meinem lieben Collegen Herrn Dr. Lissauer für seine freundliche Unterstützung bei der mikroskopischen Untersuchung. 相似文献
3.
4.
5.
I. Kaare Tesdal Werner Jaschke Mathias Bühler Ralf Adamus Thomas Filser Eggert Holm Max Georgi 《Cardiovascular and interventional radiology》1997,20(1):29-37
Purpose To evaluate prospectively our experience with transjugular intrahepatic portosystemic shunt (TIPS) using four different metallic
stents.
Methods Between November 1991 and April 1995, 57 patients (41 men and 16 women; age 35–72 years, mean 54 years) underwent the TIPS
procedure. Techniques for portal vein localization before and during TIPS were fluoroscopy, computed tomography (CT) studies,
wedged hepatic venography, arterial portography, and ultrasound. After predilation we deployed balloon-expandable (n=48) and self-expanding (n=45) metallic stents. Fifteen patients underwent variceal embolization. Initial follow-up angiograms (mean 6.9 months, range
3–24 months) were obtained in 39 of these patients.
Results Fifty-three patients (93%) had successful TIPS placement. The mean decrease in portal pressure was 42.7%. Besides fluoroscopy,
the most helpful techniques for portal vein localization were venography and CT. Residual stenosis (n=1) and late shortening (n=4) of Wallstents resulted in shunt dysfunction. The technical problems encountered with the Palmaz stent resulted from its
lack of flexibility. We combined balloon-expandable and self-expanding stents in 12 patients. The 30-day and late follow-up
(mean 11.9 months) percutaneous reintervention rates were 11.3% and 64.2%, respectively. There were no clinically significant
complications related to the TIPS insertions.
Conclusion An ideal stent does not exist for TIPS, and the authors recommend combining a Palmaz stent with a flexible self-expanding
stent. 相似文献
6.
7.
In the treatment of massive hematuria after renal biopsy, selective percutaneous vaso-occlusion with detachable balloons is an effective alternative to urological surgery, as demonstrated in the case of a 39-year-old man. A review of the literature, which records success rate of more than 90% in nonmalignant renal hemorrhage, confirms the therapeutic value of the various parenchyma-sparing embolization techniques. 相似文献
8.
9.
The treatment of neoplasia with interleukin-2 (IL-2) can be complicated by neurological deficits resembling transient Ischemic attack and stroke. We investigated whether interleukin-2 contributes to the natural course of cerebrovascular ischemia and particularly to the pathogenesis of infection-associated stroke. Plasma levels of interleukin-2 were below the level of detectability in almost all measurements. Patients with and without previous infection (n = 11, 805 ±445 U/ml vs n = 19, 824 ± 501 U/ml) did not have significantly higher levels of soluble interleukin-2 receptors than control subjects with (n = 14, 667 ± 229 U/ml) or without vascular risk factors (n = 17, 567 ± 176 U/ml). Receptor levels increased in patients during the first week after stroke (n = 15, 1157 ± 1013, p < 0.02). Levels of soluble T8 antigen (sT8) were higher in patients (n – 26, 320 ± 112 U/ml) than in healthy control subjects (n = 15, 246 ± 92 U/ml; p < 0.05) and sT8 levels increased during the first week after stroke (p < 0.05). These results reflect an immunological response to the cerebral infarct; they do not indicate a general role of the IL-2 system in the pathogenesis of ischemic stroke with or without previous infection. 相似文献
10.
Ohne Zusammenfassung 相似文献