全文获取类型
收费全文 | 8711篇 |
免费 | 373篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 100篇 |
妇产科学 | 121篇 |
基础医学 | 1121篇 |
口腔科学 | 360篇 |
临床医学 | 520篇 |
内科学 | 2433篇 |
皮肤病学 | 80篇 |
神经病学 | 504篇 |
特种医学 | 196篇 |
外科学 | 1510篇 |
综合类 | 64篇 |
预防医学 | 194篇 |
眼科学 | 139篇 |
药学 | 814篇 |
中国医学 | 27篇 |
肿瘤学 | 880篇 |
出版年
2022年 | 79篇 |
2021年 | 162篇 |
2020年 | 83篇 |
2019年 | 116篇 |
2018年 | 143篇 |
2017年 | 107篇 |
2016年 | 118篇 |
2015年 | 100篇 |
2014年 | 163篇 |
2013年 | 211篇 |
2012年 | 355篇 |
2011年 | 353篇 |
2010年 | 209篇 |
2009年 | 177篇 |
2008年 | 350篇 |
2007年 | 433篇 |
2006年 | 378篇 |
2005年 | 431篇 |
2004年 | 389篇 |
2003年 | 371篇 |
2002年 | 432篇 |
2001年 | 256篇 |
2000年 | 279篇 |
1999年 | 268篇 |
1998年 | 140篇 |
1997年 | 99篇 |
1996年 | 100篇 |
1995年 | 97篇 |
1994年 | 71篇 |
1993年 | 64篇 |
1992年 | 214篇 |
1991年 | 182篇 |
1990年 | 168篇 |
1989年 | 196篇 |
1988年 | 170篇 |
1987年 | 162篇 |
1986年 | 158篇 |
1985年 | 151篇 |
1984年 | 112篇 |
1983年 | 104篇 |
1982年 | 65篇 |
1981年 | 56篇 |
1979年 | 83篇 |
1978年 | 64篇 |
1977年 | 58篇 |
1976年 | 59篇 |
1974年 | 60篇 |
1973年 | 52篇 |
1972年 | 53篇 |
1969年 | 66篇 |
排序方式: 共有9134条查询结果,搜索用时 15 毫秒
31.
32.
J Nagata M Yamauchi K Terabe T Watanabe H Ichihara H Takagi N Nakashima 《Nihon Geka Gakkai zasshi》1987,88(4):489-492
Surgical experience of a rare case of malignant retroperitoneal cyst is reported. A 41-year-old female was admitted on Feb. 26, 1986, complaining of left lower abdominal tumor and mild abdominal pain. She underwent complete removal of an abdominal tumor located at the left flank lateral to the sigmoid colon on March 5. The tumor was well encapsulated, cystic and oval, 12 X 10 X 9 cm in size. Histologic feature of the tumor is classified as mucinous cystadenoma of low grade malignancy by WHO classification. 相似文献
33.
Vav3 modulates B cell receptor responses by regulating phosphoinositide 3-kinase activation. 总被引:7,自引:0,他引:7
Kazunori Inabe Masamichi Ishiai Andrew M Scharenberg Norman Freshney Julian Downward Tomohiro Kurosaki 《The Journal of experimental medicine》2002,195(2):189-200
To elucidate the mechanism(s) by which Vav3, a new member of the Vav family proteins, participates in B cell antigen receptor (BCR) signaling, we have generated a B cell line deficient in Vav3. Here we report that Vav3 influences phosphoinositide 3-kinase (PI3K) function through Rac1 in that phosphatidylinositol-3,4,5-trisphosphate (PIP3) generation was attenuated by loss of Vav3 or by expression of a dominant negative form of Rac1. The functional interaction between PI3K and Rac1 was also demonstrated by increased PI3K activity in the presence of GTP-bound Rac1. In addition, we show that defects of calcium mobilization and c-Jun NH2-terminal kinase (JNK) activation in Vav3-deficient cells are relieved by deletion of a PIP3 hydrolyzing enzyme, SH2 domain-containing inositol polyphosphate 5'-phosphatase (SHIP). Hence, our results suggest a role for Vav3 in regulating the B cell responses by promoting the sustained production of PIP3 and thereby calcium flux. 相似文献
34.
T Takagi T Yamaguchi T Mizoguchi T Amemiya 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1989,199(2-3):123-126
Metastasis directly to the optic nerve head without choroidal involvement is rare. We report a case of metastatic adenocarcinoma of the optic nerve head and retina with vitreous seeds which was observed in a 45-year-old Japanese male. The primary site of the lesion was clinically the upper lobe of the left lung. Tumor emboli were observed in the central retinal vein. Vitreous seeds appeared to have arisen from a necrotic area and papillary projections of the tumor. 相似文献
35.
A case of a bilateral pulmonary hernia of the lungs into the supraclavicular fossae is described. A man, aged 79, with severe chronic asthma and chronic bronchitis due to air pollution, complained of a cervical mass off and on for several years. The herniation was greater on the right side. It could be identified on physical examination by the presence of a soft painless supraclavicular bulge which was exaggerated by strain or cough. Radiologically this herniation could best be identified on lateral cervical roentgenogram. It is said that cervical lung hernia is a rare condition, but in our experience supraclavicular herniation of the lung is not unusual in cases of severe chronic obstructive lung disease. 相似文献
36.
Improvement of oxygen metabolic reserve after extracranial-intracranial bypass surgery in patients with severe haemodynamic insufficiency 总被引:8,自引:0,他引:8
Summary The effectiveness of extracranial-intracranial arterial bypass (EC-IC bypass) surgery on impaired haemodynamic status was studied in 12 patients with reduced regional cerebral perfusion pressure (rCPP) and elevated regional oxygen extraction fraction (rOEF) in the area distal to the symptomatic arterial lesion. Postoperative positron emission tomography (PET) study demonstrated a statistically significant decrease of rOEF in the operated hemispheres with disappearance of the pre-operative interhemispheric rOEF difference. Regional cerebral blood flow (rCBF) and regional cerebral oxygen metabolism (rCMRO2) were also increased in the operated hemispheres with disappearance of the pre-operative interhemispheric differences. Regional CBF/regional cerebral blood volume (rCBV) ratios of the symptomatic hemispheres were increased after surgery, but were still lower than in the contralateral hemispheres. We conclude that EC-IC bypass surgery improves impaired cerebral oxygen metabolic reserve. 相似文献
37.
38.
K Sando M Hoki R Nezu Y Takagi A Okada 《JPEN. Journal of parenteral and enteral nutrition》1992,16(1):54-58
Selenium (Se) is not routinely included in total parenteral nutrition (TPN) solution; thus, patients receiving long-term TPN may be at risk of Se deficiency, which may cause fatal cardiomyopathy. Platelet glutathione peroxidase (GSH-Px) activity, as well as Se levels and GSH-Px activity in plasma and erythrocytes during prolonged TPN, was measured in six patients with chronic gastrointestinal disease. During the time course of TPN, Se administration was discontinued for 12 weeks, and then resupplemented for another 12 weeks. Before the study period, all Se indices had been maintained within the normal range. After discontinuation of Se supplementation, a significant decrease in platelet GSH-Px activity was observed after 1 week (from 64 +/- 7 [mean +/- SD] to 39 +/- 5 U/g of protein). After resupplementation, it increased after 1 week (from 44 +/- 9 to 65 +/- 10 U/g of protein). Plasma Se indices significantly changed within 3 weeks after withdrawal and reintroduction of Se (Se: from 136 +/- 28 to 75 +/- 14 and from 61 +/- 22 to 125 +/- 33 micrograms/L; GSH-Px: from 236 +/- 50 to 140 +/- 36 and from 128 +/- 32 to 220 +/- 64 U/L). Erythrocyte Se indices showed no significant changes during the study period. The results demonstrate that platelet GSH-Px activity is the most sensitive index of Se status in TPN patients. 相似文献
39.
Comparison of p53 expression in proximal and distal gastric cancer: Histopathologic correlation and prognostic significance 总被引:2,自引:0,他引:2
Huihuan Tang MD Shuichi Hokita MD PhD Xiangming Che MD Masamichi Baba MD PhD Kuniaki Aridome MD PhD Fumio Kijima MD Gen Tanabe MD PhD Sonshin Takao MD PhD Dr. Takashi Aikou MD PhD 《Annals of surgical oncology》1997,4(6):470-474
Background: The overexpression of p53 has been found to be correlated with prognosis of some carcinomas, including gastric cancer, but
no studies have reported on its relationship to the location of gastric cancer. In the present study, we compared the p53
expression of proximal and distal gastric cancer concerning histopathology and prognosis.
Methods: A total of 170 tumors in the patients with proximal (80 cases) and distal (90 cases) gastric cancer were studied by immunohistochemical
methods.
Results: p53 immunopositivity was detected in 28.8% of all tumors. The p53-positive expression in proximal gastric cancer was higher
than in distal gastric cancer (38.8% vs. 20.0%, p<0.05). A 5-year survival analysis showed that there is no significant difference
between tumors that are p53 positive and p53 negative. No correlation was found between p53 expression and histopathology
of gastric cancer.
Conclusion: p53 nuclear staining is not useful as a prognostic indicator or as a parameter in gastric cancer. 相似文献
40.
Itsuo Yokoyama Tadamasa Yoneda Itaru Ichimura Shigehisa Kitagawa Yoshiki Okazaki Hiroshi Takagi 《Surgery today》1986,16(6):460-463
In seven patients undergoing right hemicolectomy for benign or malignant diseases, latero-lateral end anastomoses were made
using stapling devices, LS (linear stapler) and GIA (gastrointestinal anastomosis). As no complications directly related to
the anastomosis occurred, we conclude that anastomosis using stapling devices for right hemicolectomy is a safe and rapid
procedure. 相似文献