全文获取类型
收费全文 | 19680篇 |
免费 | 1121篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 637篇 |
儿科学 | 1407篇 |
妇产科学 | 827篇 |
基础医学 | 1427篇 |
口腔科学 | 1076篇 |
临床医学 | 1631篇 |
内科学 | 3492篇 |
皮肤病学 | 570篇 |
神经病学 | 1502篇 |
特种医学 | 699篇 |
外科学 | 4501篇 |
综合类 | 138篇 |
一般理论 | 8篇 |
预防医学 | 653篇 |
眼科学 | 656篇 |
药学 | 1037篇 |
1篇 | |
中国医学 | 90篇 |
肿瘤学 | 512篇 |
出版年
2024年 | 31篇 |
2023年 | 292篇 |
2022年 | 211篇 |
2021年 | 454篇 |
2020年 | 344篇 |
2019年 | 409篇 |
2018年 | 826篇 |
2017年 | 667篇 |
2016年 | 834篇 |
2015年 | 658篇 |
2014年 | 977篇 |
2013年 | 1364篇 |
2012年 | 1406篇 |
2011年 | 1656篇 |
2010年 | 994篇 |
2009年 | 579篇 |
2008年 | 1032篇 |
2007年 | 1139篇 |
2006年 | 1087篇 |
2005年 | 1172篇 |
2004年 | 1019篇 |
2003年 | 922篇 |
2002年 | 902篇 |
2001年 | 455篇 |
2000年 | 517篇 |
1999年 | 319篇 |
1998年 | 135篇 |
1997年 | 85篇 |
1996年 | 61篇 |
1995年 | 40篇 |
1994年 | 32篇 |
1993年 | 19篇 |
1992年 | 27篇 |
1991年 | 22篇 |
1990年 | 18篇 |
1989年 | 9篇 |
1988年 | 12篇 |
1987年 | 11篇 |
1986年 | 5篇 |
1985年 | 6篇 |
1983年 | 8篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 12篇 |
1978年 | 13篇 |
1976年 | 9篇 |
1975年 | 5篇 |
1974年 | 13篇 |
1969年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
42.
T. V. Peker C. Pelin H. B. Turgut A. Anıl A. Sevim 《European archives of oto-rhino-laryngology》1998,255(8):391-395
Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons
during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was
studied on Anatolian skulls. In all, 363 male and 231 female skulls were studied. The most prevalent type of suprameatal spine
resembled a crest and was found in both sexes on the right (77.6%) and left (80%) sides. The absence of a suprameatal depression
was significantly higher in females (right 9.1%; left 8.7%) than in males (right 1.7%; left 2.5%). Suprameatal depressions
were mostly shallow in female subjects, but were mostly observed in males to be at a medium depth or deep.
Received: 5 January 1998 / Accepted: 19 March 1998 相似文献
43.
Bladder cancer is one of the malignancies encountered frequently in urological practice. Since the three main treatment modalities
(surgery, chemotherapy and radiotherapy) may be used alone or together, there are many treatment options. In this paper the
current approaches in the treatment of bladder tumours are reviewed and the policy in Marmara University Hospital is described. 相似文献
44.
Faruk İldan Erdal Çetinalp Hüseyin Bagdatoglu Bülent Boyar Ziya Uzuneyüpoglu Aşkin Karadayi 《Neurosurgical review》1995,18(2):135-138
The authors describe a case of giant fusiform aneurysm of the basilar artery presenting with ischemic symptoms. Angiography and CT revealed vertebro-basilar fusiform aneurysmal dilatation. Fusiform vertebro-basilar ancurysm is associated with various complications particularly brain stem infarction. Similar lesions in the literature are reviewed and the relationship between this clinical entity and cerebral ischemia, particularly brainstem infarction are discussed. 相似文献
45.
46.
Korkusuz P Ugur Y Aşan E Aktuna Keskil Z Uluoglu C 《Okajimas folia anatomica Japonica》2002,79(2-3):83-92
Probucol is a lipid-lowering agent with an antioxidant effect; however, its influence on the liver remains unclear. The effects of probucol on hyperlipidemic rabbit liver are investigated to add a structural data on its therapeutical profile. Local albino rabbits were divided into three groups. 1) Hyperlipidemic group: fed with 1% cholesterol (150 g/kg/day) enriched chow for 2 months. 2) Probucol treated group: group 1 + intraperitoneal probucol (10 mg/kg/day) administration for 15 days. 3) Control group fed with normal chow. The blood lipid profile was investigated biochemically. Liver samples were examined electronmicroscopically. Within the parenchymal cells of group 1, the amount of rough surfaced endoplasmic reticulum was increased, its cisterna was dilated displaying a moderately electron dense substance in it and showed close apposition with the condensed mitochondria. In group 2, smooth surfaced endoplasmic reticulum was in extensive amounts filling almost all of the cytoplasm, displayed a reticular, degenerated appearance and was in close relation with the condensed, degenerated mitochondria. Probucol may cause degenerative changes on the liver parenchyme at the subcellular level. It alters the structure of these cells mainly acting on the smooth surfaced endoplasmic reticulum and the mitochondria that are known to be involved in cellular detoxification. 相似文献
47.
In vitro comparisons of induction of perforin (PFP), granzyme B (GRB), production of cytokines, and cell-mediated cytotoxicity by interleukin-2 (IL-2), interleukin-15 (IL-15), or combinational IL-2/IL-15-induced lymphokine-activated killer cells were studied in this study. Whereas IL-2-induction was associated with a decrease in cultured cell population over a 7-day period, IL-15 alone or in combination with IL-2 resulted in significant increase including cytotoxic T lymphocytes and subsets of CD56+ lymphocytes, particularly cytokine-induced killer and cytolytic natural killer-T lymphocytes. The overall PFP, GRB, and tumor necrosis factor-alpha expression in different subtypes were also significantly higher with IL-15 alone or in combination with IL-2 induction with resultant superior cytotoxicity compared to IL-2 treatment. There was no significant advantage of addition of IL-2 over IL-15 induction. These results offer further information on the cytotoxic potency of these cytokines and their mechanisms of action implicating potential use of IL-15 as part of cytokine adoptive immunotherapy. 相似文献
48.
Osteoclast-like giant-cell neoplasms of the urinary tract are rare. They are composed of ovoid or spindle-shaped mononuclear cells with evenly spaced osteoclast-like giant cells. Terminology, histogenesis, and biologic behavior of these tumors remain controversial. Six cases of osteoclast-like giant-cell neoplasms of the urinary tract were identified from the consultation files of two of the authors. Patients were all male and elderly (range 65-82), with the exception of one 39-year-old male. In all, 3/6 tumors developed in the bladder and 3/6 in the renal pelvis. Size ranged from 5 to 11 cm. One bladder and three renal pelvis tumors were high stage (pT3) at time of presentation. Adjacent to the osteoclast-like giant-cell neoplasm in the same specimen, all patients had urothelial carcinoma in situ and/or high-grade papillary urothelial carcinoma. Multinucleated cells had identical morphological and immunohistochemical properties of osteoclasts; positive for CD-68, LCA, CD51 and CD54, and negative for cytokeratins and EMA. Varying percentages of mononuclear cells expressed alpha-smooth muscle actin (4/6), desmin (1/6), S-100 (4/6), LCA (2/6) and CD68 (6/6). However, mononuclear cells were also positive for epithelial markers in 4/6 tumors (cytokeratins AE-1/AE-3, Cam 5.2, CK7 and/or EMA). p53 stained mononuclear tumor cells in three cases, paralleling the staining on the accompanying urothelial carcinoma. Ki-67 stained mononuclear tumor cells, but not osteoclast-like giant cells. Follow-up data were available in five cases. One patient developed recurrence of noninvasive urothelial carcinoma and is still alive. Four patients were dead due to disease within 15 months, three with distant metastases. The intimate association of these tumors with urothelial carcinoma along with their immunohistochemical profile supports an epithelial origin for the mononuclear cells and non-neoplastic reactive histiocytic lineage for the osteoclast-like giant cells. 相似文献
49.
Genetic variants of homocysteine metabolizing enzymes and the risk of coronary artery disease 总被引:2,自引:0,他引:2
Janosíková B Pavlíková M Kocmanová D Vítová A Veselá K Krupková L Kahleová R Krijt J Kraml P Hyánek J Zvárová J Andel M Kozich V 《Molecular genetics and metabolism》2003,79(3):167-175
It is unresolved whether elevated homocysteine in coronary artery disease (CAD) is the cause of arteriosclerosis or its consequence. In contrast, genetic variants of enzymes that metabolize homocysteine cannot be altered by arteriosclerosis. Consequently, their association with CAD would permit to imply causality. We modeled by regression analysis the effect of 11 variants in the methionine cycle upon CAD manifestation in 591 controls and 278 CAD patients. Among the examined variants only the carriership for the c.844ins68 in the cystathionine beta-synthase (CBS) gene was associated with a significantly lowered risk of CAD (OR=0.56; 95% CI=0.35-0.90 in the univariable, and OR=0.41, 95% CI=0.19-0.89 for obese people in the multivariable analysis, respectively). Healthy carriers of the c.844ins68 variant exhibited, compared to the wild type controls, significantly higher postload ratios of blood S-adenosylmethionine to S-adenosylhomocysteine (61.4 vs. 54.9, p=0.001) and of plasma total cysteine to homocysteine (8.6 vs. 7.3, p=0.004). The changes in these metabolites are compatible with an improved methylation status and with enhanced activity of homocysteine transsulfuration. In conclusion, the coincidence of clinical and biochemical effects of a common c.844ins68 CBS variant supports the hypothesis that compounds relating to homocysteine metabolism may play role in the development and/or progression of CAD. 相似文献
50.