全文获取类型
收费全文 | 14737篇 |
免费 | 820篇 |
国内免费 | 106篇 |
专业分类
耳鼻咽喉 | 161篇 |
儿科学 | 343篇 |
妇产科学 | 182篇 |
基础医学 | 1742篇 |
口腔科学 | 314篇 |
临床医学 | 991篇 |
内科学 | 3958篇 |
皮肤病学 | 190篇 |
神经病学 | 935篇 |
特种医学 | 641篇 |
外科学 | 2602篇 |
综合类 | 106篇 |
一般理论 | 2篇 |
预防医学 | 443篇 |
眼科学 | 457篇 |
药学 | 753篇 |
中国医学 | 25篇 |
肿瘤学 | 1818篇 |
出版年
2023年 | 124篇 |
2022年 | 156篇 |
2021年 | 426篇 |
2020年 | 238篇 |
2019年 | 292篇 |
2018年 | 430篇 |
2017年 | 314篇 |
2016年 | 385篇 |
2015年 | 351篇 |
2014年 | 506篇 |
2013年 | 536篇 |
2012年 | 815篇 |
2011年 | 907篇 |
2010年 | 512篇 |
2009年 | 407篇 |
2008年 | 665篇 |
2007年 | 707篇 |
2006年 | 687篇 |
2005年 | 725篇 |
2004年 | 685篇 |
2003年 | 569篇 |
2002年 | 566篇 |
2001年 | 402篇 |
2000年 | 374篇 |
1999年 | 329篇 |
1998年 | 155篇 |
1997年 | 115篇 |
1996年 | 102篇 |
1995年 | 100篇 |
1994年 | 92篇 |
1993年 | 94篇 |
1992年 | 283篇 |
1991年 | 231篇 |
1990年 | 229篇 |
1989年 | 263篇 |
1988年 | 216篇 |
1987年 | 214篇 |
1986年 | 196篇 |
1985年 | 185篇 |
1984年 | 130篇 |
1983年 | 117篇 |
1980年 | 47篇 |
1979年 | 95篇 |
1978年 | 68篇 |
1977年 | 57篇 |
1975年 | 46篇 |
1973年 | 45篇 |
1971年 | 45篇 |
1970年 | 49篇 |
1968年 | 48篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Tumor tissue is composed of tumor cells and tumor stroma. Tumor stroma contains various immune cells and non-immune stromal cells, forming a complex tumor microenvironment which plays pivotal roles in regulating tumor growth. Recent successes in immunotherapies against tumors, including immune checkpoint inhibitors, have further raised interests in the immune microenvironment of liver carcinoma. The immune microenvironment of tumors is formed because of interactions among tumor cells, immune cells and non-immune stromal cells, including fibroblasts and endothelial cells. Different patterns of immune microenvironment are observed among different tumor subtypes, and their clinicopathological significance and intertumor/intratumor heterogeneity are being intensively studied. Here, we review the immune microenvironment of hepatocellular carcinoma, intrahepatic cholangiocarcinoma and liver metastasis of colorectal adenocarcinoma, focusing on its histopathological appearance, clinicopathological significance, and relationship with histological and molecular classifications. Understanding the comprehensive histopathological picture of a tumor immune microenvironment, in addition to molecular and genetic approaches, will further potentiate the effort for precision medicine in the era of tumor-targeting immunotherapy. 相似文献
2.
3.
4.
5.
6.
Takashi Murakami Naoto Sakamoto Akihito Nagahara 《Journal of gastroenterology and hepatology》2019,34(10):1685-1695
Sessile serrated adenoma/polyps (SSA/Ps) are early precursor lesions in the serrated neoplasia pathway, which results in BRAF‐mutated colorectal carcinomas with not only high levels of microsatellite instability but also microsatellite stable. SSA/Ps with advanced histology, including cytological dysplasia or minimally invasive carcinomas, are important lesions because SSA/Ps are considered major contributors to “interval cancers” and these lesions can rapidly become dysplastic or invasive carcinomas. Clinicopathologically, SSA/Ps with dysplasia or invasive carcinoma were associated with advanced age, female sex, and proximal colon. Although SSA/Ps with submucosal invasive carcinoma were smaller and invaded less deeply into the submucosal layer than conventional tubular adenomas with submucosal invasive carcinoma, SSA/Ps with submucosal invasive carcinoma frequently had a mucinous component and exhibited a higher potential for lymphatic invasion and lymph node metastasis. In an SSA/P series, endoscopic characteristics, including (semi)pedunculated morphology, double elevation, central depression, and reddishness, may help accurately diagnose SSA/Ps with advanced histology. Removal of SSA/Ps with dysplasia or invasive carcinoma was recommended. Endoscopic treatment such as endoscopic mucosal resection or endoscopic submucosal dissection is useful for those lesions. However, surgical resection with lymph node dissection might be indicated when SSA/Ps with invasive carcinoma are endoscopically suspected, because these have the high risk of lymph node metastasis. Greater awareness may promote further research into improving the detection, recognition, and complete resection rates of SSA/Ps with dysplasia or invasive carcinoma and reduce the interval cancer rates. 相似文献
7.
8.
9.
Kei Kamide Yoshihiro Kokubo Hironori Hanada Junko Nagura Jin Yang Shin Takiuchi Chihiro Tanaka Mariko Banno Yoshikazu Miwa Masayoshi Yoshii Tetsutaro Matayoshi Hisayo Yasuda Takeshi Horio Akira Okayama Hitonobu Tomoike Yuhei Kawano Toshiyuki Miyata 《Hypertension research》2006,29(4):243-252
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese. 相似文献
10.
Daisuke Kubota Chizuru Takishima Ken-ichi Ishii Takahiro Kawamura Tomoko Matsumoto Yasuhiro Itsui Eriko Okada Seishin Chin Shinya Oooka Kiichiro Tsuchiya Akihiro Araki Naoya Sakamoto Tatsuya Miyata Takanori Kanai Mamoru Watanabe 《Nihon Shokakibyo Gakkai zasshi》2006,103(9):1044-1049
A 23-year-old man was admitted for treatment of acute exacerbation of ileitis and perianal abscess caused by Crohn's disease. After incision and drainage of the abscess, coupled with antibiotic therapy, 6-mercaptopurine (6-MP) was commenced. His white blood cell (WBC) count on day 12 after initiation of 6-MP was not decreased. However, on day 24 he was re-admitted because of severe myelosuppression (WBC: 300/microl), which was complicated by the recurrence of the perianal abscess. Myelosuppression was prolonged and required the administration of granulocyte colony stimulating factor (G-CSF). G-CSF was continued for 17 days to achieve recovery of his WBC count to a normal level. 相似文献