全文获取类型
收费全文 | 33204篇 |
免费 | 1712篇 |
国内免费 | 223篇 |
学科分类
医药卫生 | 35139篇 |
出版年
2023年 | 175篇 |
2022年 | 112篇 |
2021年 | 662篇 |
2020年 | 390篇 |
2019年 | 491篇 |
2018年 | 708篇 |
2017年 | 550篇 |
2016年 | 695篇 |
2015年 | 692篇 |
2014年 | 1007篇 |
2013年 | 1087篇 |
2012年 | 1833篇 |
2011年 | 2097篇 |
2010年 | 1197篇 |
2009年 | 1037篇 |
2008年 | 1747篇 |
2007年 | 1965篇 |
2006年 | 1936篇 |
2005年 | 2084篇 |
2004年 | 2055篇 |
2003年 | 2043篇 |
2002年 | 1941篇 |
2001年 | 646篇 |
2000年 | 594篇 |
1999年 | 631篇 |
1998年 | 517篇 |
1997年 | 403篇 |
1996年 | 352篇 |
1995年 | 352篇 |
1994年 | 314篇 |
1993年 | 295篇 |
1992年 | 429篇 |
1991年 | 360篇 |
1990年 | 347篇 |
1989年 | 364篇 |
1988年 | 323篇 |
1987年 | 305篇 |
1986年 | 290篇 |
1985年 | 278篇 |
1984年 | 229篇 |
1983年 | 187篇 |
1982年 | 112篇 |
1981年 | 109篇 |
1980年 | 110篇 |
1979年 | 145篇 |
1978年 | 115篇 |
1977年 | 99篇 |
1975年 | 72篇 |
1974年 | 67篇 |
1972年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 31 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.
Hori Hiroki Ohta Asuka Matsui Honami Yano Kanako Morita-Tominaka Miyuki Linn Zayar Masumoto Daisuke Okumura Yosuke Okamura Satoshi Kurihara Kosuke Hayakawa Akira Rikiishi Takeshi Kobayashi Kyoko 《International journal of clinical oncology / Japan Society of Clinical Oncology》2022,27(1):245-252
International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change... 相似文献
3.
Toshihiro Yoshitake Akira Takeda Kensaku Ohki Yuko Inoue Takanori Yamawaki Saori Otsuka Minekatsu Akimoto Mitsuru Nemoto Yasuhito Shimakura Akio Sato 《The Journal of dermatology》2015,42(7):735-738
Finasteride is standard medical treatment for androgenetic alopecia; however, no large studies with 5 years or more of follow up have been performed in Japan. The authors followed Japanese men with androgenetic alopecia treated with finasteride for 5 years to evaluate long‐term treatment efficacy. Of 903 men treated with finasteride (1 mg/day), 801 patients were evaluated over 5 years by modified global photographic assessment. Although the proportion of improvement was high (99.4%), modified global photographic assessment scores after 5 years of treatment were lower in patients with more advanced disease as measured by the modified Norwood–Hamilton scale. After separating patients into “sufficient” and “insufficient” efficacy groups according to the modified global photographic assessment score after 5 years (scores ≥6 and <6, respectively), multivariate analysis showed that independent risk factors of insufficient efficacy were age at start of treatment of 40 years or more (P = 0.021) and classification on the modified Norwood–Hamilton scale (P < 0.001), whereas presence of stress at start of treatment was a negative predictor (P = 0.025). In conclusion, continuous finasteride treatment for 5 years improved androgenetic alopecia with sustained effect among Japanese. Younger age and less advanced disease at start of treatment were the key predictors of higher finasteride efficacy. 相似文献
4.
5.
6.
7.
Akira Mogi Toshiki Yajima Kenji Tomizawa Ryoichi Onozato Shigebumi Tanaka Hiroyuki Kuwano 《Annals of thoracic and cardiovascular surgery》2015,21(5):435-439
Purpose: Small pulmonary lesions that include ground-glass attenuation have been increasingly discovered because of progressive imaging diagnostic technologies. Despite the detection of such small lesions, sometimes it is quite difficult to localize them because of their size or considerable depth from the visceral pleura. In the present study, we examined the usefulness of computed tomography-guided lipiodol marking for thoracoscopic resection of impalpable pulmonary nodules.Methods: Fifty-six patients with an undiagnosed peripheral lesion(s) of the lung who had undergone preoperative computed tomography-guided lipiodol marking followed by video-assisted thoracoscopic surgery were studied.Results: All of the nodules were successfully marked by computed tomography-guided lipiodol marking, and all except for one case were localized by means of intraoperative fluoroscopy as clear spots. With regard to complications, pneumothorax occurred in 21 patients (37.5%), and only one patient required transient drainage. Although hemorrhaging in the lung parenchyma and hemosputum occurred in nine patients (16.1%) and one patient (1.8%), respectively, no patients were in serious condition. No intra- or postoperative mortality or morbidity was observed.Conclusion: Preoperative computed tomography-guided lipiodol marking of small or impalpable pulmonary nodules is a safe and useful procedure for thoracoscopic resection of the lung. 相似文献
8.
Journal of Neurology - 相似文献
9.
10.
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