全文获取类型
收费全文 | 26708篇 |
免费 | 1418篇 |
国内免费 | 104篇 |
专业分类
耳鼻咽喉 | 413篇 |
儿科学 | 1125篇 |
妇产科学 | 895篇 |
基础医学 | 4272篇 |
口腔科学 | 600篇 |
临床医学 | 2212篇 |
内科学 | 5273篇 |
皮肤病学 | 541篇 |
神经病学 | 2605篇 |
特种医学 | 1233篇 |
外国民族医学 | 14篇 |
外科学 | 3790篇 |
综合类 | 135篇 |
一般理论 | 3篇 |
预防医学 | 1400篇 |
眼科学 | 501篇 |
药学 | 1425篇 |
中国医学 | 20篇 |
肿瘤学 | 1773篇 |
出版年
2022年 | 213篇 |
2021年 | 360篇 |
2020年 | 237篇 |
2019年 | 327篇 |
2018年 | 414篇 |
2017年 | 352篇 |
2016年 | 491篇 |
2015年 | 501篇 |
2014年 | 672篇 |
2013年 | 883篇 |
2012年 | 1193篇 |
2011年 | 1270篇 |
2010年 | 636篇 |
2009年 | 691篇 |
2008年 | 1153篇 |
2007年 | 1268篇 |
2006年 | 1156篇 |
2005年 | 1188篇 |
2004年 | 990篇 |
2003年 | 990篇 |
2002年 | 917篇 |
2001年 | 909篇 |
2000年 | 941篇 |
1999年 | 793篇 |
1998年 | 364篇 |
1997年 | 290篇 |
1996年 | 233篇 |
1995年 | 223篇 |
1994年 | 197篇 |
1993年 | 192篇 |
1992年 | 487篇 |
1991年 | 517篇 |
1990年 | 496篇 |
1989年 | 422篇 |
1988年 | 398篇 |
1987年 | 410篇 |
1986年 | 399篇 |
1985年 | 395篇 |
1984年 | 278篇 |
1983年 | 220篇 |
1982年 | 145篇 |
1981年 | 148篇 |
1979年 | 261篇 |
1978年 | 185篇 |
1977年 | 155篇 |
1976年 | 162篇 |
1975年 | 168篇 |
1974年 | 192篇 |
1973年 | 167篇 |
1972年 | 154篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Setting goals to maintain hope. 总被引:3,自引:0,他引:3
2.
3.
I Immonen K Friberg C Gr?nhagen-Riska E von Willebrand F Fyhrquist 《Acta ophthalmologica》1986,64(5):519-521
Angiotensin-converting enzyme (ACE) was studied immunohistochemically in conjunctival biopsies from 6 patients with systemic sarcoidosis, 4 patients with posterior non-sarcoid uveitis and in specimens from 4 patients with chalazion of the eyelid. Specimens with sarcoid granulomas showed intense ACE-positive immunoreactivity in epitheloid cells of the granuloma, whereas chalazion granulomas did not contain ACE-immunoreactivity. There was no difference in staining patterns between specimens without granulomas. Thus immunohistochemical staining for ACE may be of help in differentiating conjunctival granulomatous tissue of a chalazion from sarcoid granuloma. 相似文献
4.
Out of 24 patients with laryngeal papillomatosis 6 (5 female, 1 male) suffered from repeated relapses and underwent long-term treatment with alpha-IFN-therapy. Age at onset of the disease: 1 5/12-16 2/12 years. Duration of illness: 1-7 years, with several relapses were treated surgically and with laser-coagulation. Three out of 6 patients had a tracheal cannula and were cauterized by podophylline at 2-4 week intervals. IFN was given in dosages of 5-20 X 10(4) U/kg 2 or 3 times a week. IFN-dosage for each patient was determined using the induction kinetics of (2'-5')-oligo(A)synthetase (OAS) in the mononuclear cells of the circulating blood of patients with laryngeal papillomatosis. A continuous effect could be achieved by the dose of IFN determined in the described way always before OAS activity decreased to its initial level. All 6 patients responded favorably to the alpha-IFN-therapy. Two patients treated only with IFN showed remission without relapses. In 2 cases IFN was successfully used to prevent relapses after surgical treatment and laser-coagulation. In 2 patients with papillomatosis extending into the main bronchi the disease could only be brought to a standstill, i.e. it was not necessary to remove the papillomas. Two out of 3 patients with laryngeal papillomatosis could be decannulated. Long-term therapy following the above described principles is efficient and without significant side-effects. Three patients are in treatment for more than 3 10/12 years. 相似文献
5.
W. Ziegler D. von Cramon 《European archives of psychiatry and clinical neuroscience》1986,236(1):44-49
Summary This paper deals with a particular aspect of speech motor control in patients suffering from apraxia of speech. Three experiments are reported concerning the phase relations between individual speech gestures. These include the timing of laryngeal, velar and labial movements relative to lingual gestures.A total of 8 patients and 12 normal controls were examined using speech material which was designed according to appropriate phonetic paradigms. Evaluation was performed on the basis of speech signal parameters referring to the kinematics of inter-articulatory phasing. Deviations of the patient group were found in all three experiments. This suggests that disturbed phase relations of individual speech movements are a general feature of apraxic speech. It is further hypothesized that the described motor symptoms are the origin of a variety of phonemic errors. Support for this view is provided by appropriate examples which refer to the examined paradigms. By this argument, much of the disturbed phonemic structure of apraxic speech may be accounted for by timing deficits. 相似文献
6.
Humoral immune aberrations may occur in the cerebrospinal fluid (CSF) of patients with lymphoproliferative and other neoplastic diseases infiltrating the central nervous system (CNS). Such aberrations may be of diagnostic importance. We therefore studied CSF and serum from 47 patients with lymphoproliferative diseases and from 16 patients with various nonlymphoid neoplasias; 17 patients and 12 patients, respectively, had neoplastic CNS involvement. Elevated CSF IgM index and oligoclonal IgG bands in CSF and serum were commonly found, especially in patients with CNS involvement. Cerebrospinal fluid IgG and IgA indexes were usually normal. Increased CSF to serum albumin ratio, reflecting blood-brain barrier dysfunction, and increased CSF beta 2-microglobulin concentration were most common in patients with CNS involvement. The results indicate that neoplastic CNS disease should be borne in mind when CSF humoral immune aberrations are found. 相似文献
7.
8.
9.
F J von Baumgarten G Burkhard D Englert P Kraus H G Mertens G Müller-Berghaus H Przuntek 《European neurology》1987,27(3):149-154
Fibrinopeptide A (FPA), platelet-secreted protein, platelet factor 4 and beta-thromboglobulin were determined in the cerebrospinal fluid of patients who had suffered from subarachnoid hemorrhage and were treated with 6 g tranexamic acid or 4 million KIU aprotinin to prevent rebleeding. Platelet-secreted proteins and FPA were cleared from the cerebrospinal fluid within 3 days after bleeding. Their vasoactive and thrombotic capability is limited to the initiation period of vasospasm that usually comes to clinical observation 3-8 days after bleeding. Increased thrombotic activity of the cerebrospinal fluid, as reflected by high levels of FPA and platelet-secreted protein, seemed to promote the occurrence of neurological deficits. 相似文献
10.
Apolipoprotein E isoforms were determined in 139 unrelated patients with retinitis pigmentosa (RP). When compared to prevalence rates for the general population in Germany, an increased prevalence was observed for phenotypes E2/E2: 10.1 vs. 1.0% (p less than 0.001), E2/E3: 19.4 vs. 12.0% (p less than 0.05), and E2/E4: 5.8 vs. 1.5% (n.s.), while the prevalence appeared to be reduced for phenotypes E3/E3: 48.9 vs. 59.8% (n.s.) E3/E4: 13.7 vs. 22.9% (p less than 0.05), and E4/E4: 2.2 vs. 2.8% (n.s.). These findings suggest that genetically determined abnormalities of plasma lipoprotein metabolism may be associated with some forms of RP. 相似文献