全文获取类型
收费全文 | 129852篇 |
免费 | 12768篇 |
国内免费 | 9006篇 |
专业分类
耳鼻咽喉 | 1039篇 |
儿科学 | 1703篇 |
妇产科学 | 979篇 |
基础医学 | 10847篇 |
口腔科学 | 2384篇 |
临床医学 | 15571篇 |
内科学 | 14411篇 |
皮肤病学 | 1196篇 |
神经病学 | 4822篇 |
特种医学 | 5282篇 |
外国民族医学 | 39篇 |
外科学 | 13215篇 |
综合类 | 30930篇 |
现状与发展 | 28篇 |
一般理论 | 16篇 |
预防医学 | 12476篇 |
眼科学 | 2228篇 |
药学 | 14951篇 |
170篇 | |
中国医学 | 11020篇 |
肿瘤学 | 8319篇 |
出版年
2024年 | 597篇 |
2023年 | 1830篇 |
2022年 | 4597篇 |
2021年 | 5691篇 |
2020年 | 4804篇 |
2019年 | 3307篇 |
2018年 | 3533篇 |
2017年 | 3922篇 |
2016年 | 3273篇 |
2015年 | 5558篇 |
2014年 | 7074篇 |
2013年 | 7870篇 |
2012年 | 11504篇 |
2011年 | 12417篇 |
2010年 | 9936篇 |
2009年 | 8363篇 |
2008年 | 9102篇 |
2007年 | 8847篇 |
2006年 | 8086篇 |
2005年 | 6911篇 |
2004年 | 4862篇 |
2003年 | 4122篇 |
2002年 | 3447篇 |
2001年 | 2916篇 |
2000年 | 2429篇 |
1999年 | 1478篇 |
1998年 | 828篇 |
1997年 | 795篇 |
1996年 | 634篇 |
1995年 | 571篇 |
1994年 | 431篇 |
1993年 | 304篇 |
1992年 | 262篇 |
1991年 | 208篇 |
1990年 | 201篇 |
1989年 | 195篇 |
1988年 | 148篇 |
1987年 | 139篇 |
1986年 | 105篇 |
1985年 | 101篇 |
1984年 | 55篇 |
1983年 | 33篇 |
1982年 | 33篇 |
1981年 | 25篇 |
1980年 | 15篇 |
1979年 | 17篇 |
1978年 | 7篇 |
1973年 | 5篇 |
1972年 | 6篇 |
1971年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
目的 探讨嗜酸性胃炎的CT表现.方法 4例嗜酸性胃炎均行CT检查并经实验室检查、胃镜和病理证实,其中2例又经手术病理证实.男女各2例,年龄25~42岁,平均32.7岁.结果 4例嗜酸性胃炎均显示胃壁弥漫性增厚,最厚约11~15 mm,边缘光滑,胃腔正常.2例合并腹水,1例合并回结肠套叠. 结论 CT可以显示胃壁弥漫性增厚,边缘光滑,结合实验室检查及胃镜和病理检查,可提示嗜酸性胃炎的可能. 相似文献
22.
Gerald S. Lipshutz Harish Mahanty Sandy Feng Ryutaro Hirose Peter G. Stock Sang-Mo Kang rew M. Posselt Chris E. Freise 《American journal of transplantation》2005,5(2):366-373
With the introduction of more potent immunosuppressive agents, rejection has decreased in simultaneous pancreas/kidney transplant (SPK) recipients. However, as a consequence, opportunistic infections have increased. The purpose of this report is to outline the course of SPK patients who developed polyomavirus-associated nephropathy (PVAN). A retrospective review of 146 consecutive SPK recipients from January 1, 1996 to December 31, 2002 was performed. Immunosuppression, rejection and development of PVAN were reviewed. Nine patients were identified. All received induction with either OKT3 or thymoglobulin. Immunosuppression included tacrolimus/cyclosporine, MMF/azathioprine and sirolimus/prednisone. Two patients were treated for kidney rejection prior to the diagnosis of PVAN. Time to diagnosis was an average of 359.3 days post-transplantation. Immunosuppression was decreased but five ultimately lost function. However, none developed pancreatic abnormalities as demonstrated by normal glucose and amylase. Two underwent renal retransplantation after PVAN diagnosis and both have normal kidney function. PVAN was the leading cause of renal loss in SPK patients in the first 2 years after transplantation and is a serious concern for SPK recipients. The pancreas, however, is spared from evidence of infection, and no pancreatic rejection occurred when immunosuppression was decreased. 相似文献
23.
24.
25.
克劳塞维茨《战争论》认为防御这种作战形式就其本身来说比进攻这种形式强。太极拳尤以老庄道家学说为宗,不强调进攻,而注重防御,两者有相似之处。 相似文献
26.
27.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献
28.
改良W形回肠代膀胱术的疗效观察(附36例报告) 总被引:5,自引:0,他引:5
目的 :探讨改良W形回肠代膀胱术的疗效。方法 :对 36例膀胱肿瘤患者行根治性膀胱切除、W形回肠代膀胱术 ,并对术式进行改进。结果 :36例手术时间平均 4 .2h。术后 31例随访 4~ 19个月 ,平均 10 .6个月 ,无严重并发症 ,均无瘤生存。患者一般于术后 3周自主可控性排尿 ,日间尿控率为 10 0 % ,术后 3、6、12个月夜间尿失禁发生率分别为 2 2 .5 %、11.1%及 6 .2 %。术后 6个月尿动力学检查膀胱容量 (36 0± 30 )ml,最大尿流率 (13.6± 2 .6 )ml/s,剩余尿量 (11.5± 5 .8)ml,充盈期膀胱压力明显低于尿道闭合压。新膀胱造影发现新膀胱呈球形 ,完全位于盆腔 ,未见输尿管反流。B超及IVU检查发现原上尿路积水 4例均明显减轻 ,其余未发现输尿管狭窄和上尿路积水征象。无高氯性酸中毒 ,肾功能正常。结论 :改良W形回肠代膀胱术手术时间短 ,操作简单 ,创伤轻 ,并发症少 ;新膀胱容量大 ,内压低 ,顺应性好 ,功能接近于正常膀胱 ,保持原位排尿 ,明显提高了患者术后生活质量 ,值得临床推广应用。 相似文献
29.
Three kinds of lectins (UEA-I, ConA, PNA) were used to study normal, dysplastic, neoplastic nasopharyngeal epithelium by lectin affinitive histochemical method. UEA-I (ulex europeus agglutinin-I) displayed membrane distribution in normal squamous epithelium, but most of nasopharyngeal carcinoma cells were negative. Notably, severe dysplastic epithelium (precancerous lesion) exhibited a strong membranous and cytoplasmic affinity, which contrasted sharply with the normal epithelium and carcinoma cells. The statistically significant difference in the content and distribution of lectin UEA-I in these three groups suggest that UEA-I is a hopeful marker for diagnosing precancerous lesion of the nasopharynx. However, PNA and ConA are of less diagnostic value.
相似文献
30.
目的 :观察血清保存方法对促甲状腺激素 (TSH)结果的影响。方法 :将甲状腺功能正常、异常患者共 10份血清 ,采用不同血清量、不同条件分组保存后测定 TSH。结果 :保存方法对 TSH结果有一定的影响。结论 :用于 TSH血清的保存量要多、要密封管口、低温保存。 相似文献