首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   228925篇
  免费   21092篇
  国内免费   10047篇
耳鼻咽喉   2887篇
儿科学   5163篇
妇产科学   5478篇
基础医学   36282篇
口腔科学   6287篇
临床医学   18832篇
内科学   27858篇
皮肤病学   5072篇
神经病学   11429篇
特种医学   7019篇
外国民族医学   159篇
外科学   21529篇
综合类   36229篇
现状与发展   61篇
预防医学   6828篇
眼科学   4041篇
药学   17124篇
  77篇
中国医学   6829篇
肿瘤学   40880篇
  2024年   505篇
  2023年   3317篇
  2022年   6198篇
  2021年   8583篇
  2020年   7436篇
  2019年   7052篇
  2018年   7124篇
  2017年   7695篇
  2016年   8289篇
  2015年   9250篇
  2014年   13812篇
  2013年   14709篇
  2012年   13063篇
  2011年   14559篇
  2010年   11925篇
  2009年   11640篇
  2008年   12073篇
  2007年   12391篇
  2006年   11321篇
  2005年   10283篇
  2004年   9038篇
  2003年   7771篇
  2002年   6562篇
  2001年   5718篇
  2000年   4709篇
  1999年   4230篇
  1998年   3866篇
  1997年   3558篇
  1996年   3154篇
  1995年   2789篇
  1994年   2445篇
  1993年   1976篇
  1992年   1618篇
  1991年   1487篇
  1990年   1155篇
  1989年   1085篇
  1988年   1020篇
  1987年   825篇
  1986年   730篇
  1985年   966篇
  1984年   859篇
  1983年   595篇
  1982年   648篇
  1981年   522篇
  1980年   421篇
  1979年   336篇
  1978年   231篇
  1977年   176篇
  1976年   141篇
  1975年   54篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
102.
103.
《Neuro-Chirurgie》2022,68(2):196-201
BackgroundTumor-to-tumor metastases are extremely rarely reported lesions, which usually involve an indolent lesion hosting a more aggressive neoplasm. We present an unusual initial manifestation of a previously unknown clear cell renal cell carcinoma as a tumor-to-tumor metastasis in a typical meningothelial meningioma.Case reportA 73-year old patient with transient left slight monoparesis was addressed to our Neurosurgical Department after being evaluated by his general practitioner and passing a cerebral MRI which revealed a right frontotemporal mass attached to the meninge. At presentation, no deficits were identified; therefore an elective surgery was proposed. Histological analysis revealed a typical meningothelial meningioma containing a metastatic clear cell renal cell carcinoma. Additional thoraco-abdominal computer tomography identified a 6 cm diameter lesion within the right kidney with radiological features highly suggestive of a primary clear cell renal cell carcinoma.ConclusionOur case highlights the need for a specialized neuropathological approach to clinical and imagistic indolent meningiomas, as they may require important differential diagnosis that can highly impact the treatment and follow-up of brain tumor patients.  相似文献   
104.
Urothelial cell carcinoma (UCC) of the bladder is one of the most common malignancies, causing considerable morbidity and mortality worldwide. It is unique among the epithelial carcinomas as two distinct pathways to tumourigenesis appear to exist: low grade, recurring papillary tumours usually contain oncogenic mutations in FGFR3 or HRAS whereas high grade, muscle invasive tumours with metastatic potential generally have defects in the pathways controlled by the tumour suppressors p53 and retinoblastoma. Over the last two decades, a number of transgenic mouse models of UCC, containing deletions or mutations of key tumour suppressor genes or oncogenes, have helped us understand the mechanisms behind tumour development. In this summary, I present my work investigating the role of the WNT signalling cascade in UCC.  相似文献   
105.
106.
107.
肿瘤的转移前微环境(pre-metastatic niche,PMN)特指原发肿瘤灶为肿瘤细胞远处播散和定植准备的微环境,此微环境的六个特征包括炎症、免疫抑制、血管生成/血管通透性、亲器官性、重编程和淋巴管生成。PMN形成的关键成分包括肿瘤源性分泌因子、细胞外囊泡(含外泌体)、骨髓源性细胞、免疫抑制细胞和宿主基质细胞等,其中,外泌体作为细胞间重要的信使,在肿瘤PMN的形成中具有重要作用。本综述就外泌体在肿瘤PMN形成中的作用进行探讨。  相似文献   
108.
109.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents.  相似文献   
110.
miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号