全文获取类型
收费全文 | 4925篇 |
免费 | 216篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 40篇 |
儿科学 | 95篇 |
妇产科学 | 95篇 |
基础医学 | 679篇 |
口腔科学 | 62篇 |
临床医学 | 326篇 |
内科学 | 1415篇 |
皮肤病学 | 106篇 |
神经病学 | 321篇 |
特种医学 | 159篇 |
外科学 | 796篇 |
综合类 | 15篇 |
预防医学 | 134篇 |
眼科学 | 88篇 |
药学 | 367篇 |
中国医学 | 5篇 |
肿瘤学 | 457篇 |
出版年
2023年 | 17篇 |
2022年 | 35篇 |
2021年 | 67篇 |
2020年 | 27篇 |
2019年 | 37篇 |
2018年 | 53篇 |
2017年 | 40篇 |
2016年 | 75篇 |
2015年 | 66篇 |
2014年 | 101篇 |
2013年 | 138篇 |
2012年 | 215篇 |
2011年 | 241篇 |
2010年 | 124篇 |
2009年 | 126篇 |
2008年 | 222篇 |
2007年 | 258篇 |
2006年 | 286篇 |
2005年 | 323篇 |
2004年 | 287篇 |
2003年 | 293篇 |
2002年 | 257篇 |
2001年 | 160篇 |
2000年 | 154篇 |
1999年 | 162篇 |
1998年 | 86篇 |
1997年 | 73篇 |
1996年 | 64篇 |
1995年 | 62篇 |
1994年 | 51篇 |
1993年 | 53篇 |
1992年 | 113篇 |
1991年 | 108篇 |
1990年 | 92篇 |
1989年 | 96篇 |
1988年 | 75篇 |
1987年 | 59篇 |
1986年 | 54篇 |
1985年 | 54篇 |
1984年 | 34篇 |
1983年 | 48篇 |
1982年 | 28篇 |
1981年 | 22篇 |
1980年 | 15篇 |
1979年 | 22篇 |
1976年 | 14篇 |
1975年 | 21篇 |
1970年 | 17篇 |
1969年 | 22篇 |
1968年 | 16篇 |
排序方式: 共有5160条查询结果,搜索用时 9 毫秒
91.
Shigeki Shichijo Kouichi Azuma Nobukazu Komatsu Masaaki Ito Yoshiaki Maeda Yuki Ishihara Kyogo Itoh 《Clinical cancer research》2004,10(17):5828-5836
PURPOSE: The purpose of this work was to provide a scientific basis for specific immunotherapy of colon cancer. EXPERIMENTAL DESIGN: This study focused on identification of colon tumor-associated antigens and HLA-A2-restricted and tumor-reactive cytotoxic T lymphocytes (CTLs) generated from tumor-infiltrating lymphocytes of a colon cancer patient. A gene expression cloning method was used to identify genes coding for tumor antigens. Fifty-six peptides with HLA-A2-binding motifs encoded by these proteins were examined for their ability to induce HLA-A2-restricted and tumor-reactive CTLs. RESULTS: We identified the following three genes coding for proliferation-related proteins: thymidylate synthase (TYMS), which is involved in chemoresistance (5-fluorouracil); 5'-aminoimidazole-4-carboxamide-1-beta-d-ribonucleotide transfolmylase/inosinicase (AICRT/I); and phosphoglycerate kinase 1 (PKG1), which was secreted by tumor cells and involved in the angiogenic process. TYMS was preferentially expressed in tumor cells, whereas AICRT/I and PKG1 were equally expressed in both cancer cells and normal tissues at the mRNA level. Among 56 peptides with HLA-A2-binding motifs encoded by these proteins, 8 peptides were recognized by the CTLs, and 5 of 8 peptides were also recognized by the CTL precursors without ex vivo activation in the peripheral blood of colon cancer patients. Furthermore, four of them (one each from TYMS and PKG1 and two from AICRT/1) possessed the ability to induce HLA-A2-restricted and peptide-specific CTLs cytotoxic to colon tumor cells in peripheral blood mononuclear cells of colon cancer patients. CONCLUSIONS: TYMS and PGK1, as well as their epitope peptides, might be appropriate target molecules for specific immunotherapy of HLA-A2(+) colon cancer patients because of the positive role of TYMS and PGK1 in chemoresistance (5-fluorouracil) and angiogenesis of tumor cells, respectively. 相似文献
92.
Inoue K Saito M Kanai T Kawata T Shigematsu N Uno T Isobe K Liu CH Ito H 《The American journal of Chinese medicine》2008,36(3):625-634
The honeybee product propolis and its extracts are known to have biological effects such as antibiotic, anti-viral, anti-inflammatory and anti-tumor activities. This study was designed to investigate whether water-soluble propolis (WSP) inhibits tumor growth. The tumor cell line used was mouse sarcoma 180 (S-180), and its growth was determined in vitro and in vivo with exposure to different concentrations of WSP. The effects of WSP on tumor cells in vitro were evaluated by measuring the intracellular uptake of 3H-thymidine. 3H-thymidine uptake was inhibited in accordance with the concentration of WSP. The minimum concentration of WSP necessary for 3H-thymidine uptake inhibition was 1.0 microg/ml and uptake was suppressed to 88% of the level in non-treated cells at this concentration. In an experiment using tumor-bearing mice, oral administration of WSP was begun 24 hours after transplantation of S-180 cells. WSP was administered to the mice 5 times, every other day for 10 days. The doses were 320 mg/kg (10 mg/mouse) or 960 mg/kg (30 mg/mouse) of body weight. All mice were sacrificed 10 days after transplantation, and tumor growth was evaluated. The orally administered WSP significantly inhibited the growth of transplanted tumors (p < 0.05). Furthermore, histological findings revealed a significant reduction in mitotic cells and tumor invasion of the muscular tissue at both dose-levels of WSP. 相似文献
93.
This review and case study report considers the evidence to indicate that the progress of wound healing is negatively affected by the presence of stressors and in circumstances where patients are in pain. It considers the relationship between perceptions of pain, stress and delayed wound healing with a specific focus on guidance for clinical practice. It is appreciated that although the literature has examined these issues in the management of acute wounds, demonstrating that psychological stress can have detrimental effects on the wound‐healing process, the evidence to support this link in relation to chronic wounds is limited. The review considers evidence indicating that punch biopsy wounds heal more slowly in subjects under stress on account of caring for family members with long‐term illnesses and also considers briefly the relationship between cortisol secretion in response to stress and the consequent influences on cytokine levels and the wound‐healing process. 相似文献
94.
Naohiro Iwata Mari Okazaki Meiyan Xuan Shinya Kamiuchi Hirokazu Matsuzaki Yasuhide Hibino 《Nutrients》2014,6(4):1554-1577
Diabetes mellitus is known to exacerbate cerebral ischemic injury. In the present study, we investigated antiapoptotic and anti-inflammatory effects of oral supplementation of ascorbic acid (AA) on cerebral injury caused by middle cerebral artery occlusion and reperfusion (MCAO/Re) in rats with streptozotocin-induced diabetes. We also evaluated the effects of AA on expression of sodium-dependent vitamin C transporter 2 (SVCT2) and glucose transporter 1 (GLUT1) after MCAO/Re in the brain. The diabetic state markedly aggravated MCAO/Re-induced cerebral damage, as assessed by infarct volume and edema. Pretreatment with AA (100 mg/kg, p.o.) for two weeks significantly suppressed the exacerbation of damage in the brain of diabetic rats. AA also suppressed the production of superoxide radical, activation of caspase-3, and expression of proinflammatory cytokines (tumor necrosis factor-α and interleukin-1β) in the ischemic penumbra. Immunohistochemical staining revealed that expression of SVCT2 was upregulated primarily in neurons and capillary endothelial cells after MCAO/Re in the nondiabetic cortex, accompanied by an increase in total AA (AA + dehydroascorbic acid) in the tissue, and that these responses were suppressed in the diabetic rats. AA supplementation to the diabetic rats restored these responses to the levels of the nondiabetic rats. Furthermore, AA markedly upregulated the basal expression of GLUT1 in endothelial cells of nondiabetic and diabetic cortex, which did not affect total AA levels in the cortex. These results suggest that daily intake of AA attenuates the exacerbation of cerebral ischemic injury in a diabetic state, which may be attributed to anti-apoptotic and anti-inflammatory effects via the improvement of augmented oxidative stress in the brain. AA supplementation may protect endothelial function against the exacerbated ischemic oxidative injury in the diabetic state and improve AA transport through SVCT2 in the cortex. 相似文献
95.
96.
97.
98.
99.
Inoue N Ohkusa T Nao T Lee JK Matsumoto T Hisamatsu Y Satoh T Yano M Yasui K Kodama I Matsuzaki M 《Journal of the American College of Cardiology》2004,44(4):914-922
OBJECTIVES: The aim of this study was to investigate the effects of rapid electrical stimulation (RES) of contraction on the expression of connexin (Cx)43 gap junction in neonatal rat cultured ventricular myocytes and the consequent changes of conduction properties. BACKGROUND: The expression and distribution of gap junctions in cardiac muscle can be changed readily under a variety of pathological conditions because of dynamic turnover of Cxs. The effects of RES of contraction on gap junction remodeling are not well understood. METHODS: Neonatal rat ventricular myocytes cultured for five days were subjected to RES (field stimulation) at 3.0 Hz for up to 120 min. RESULTS: Rapid electrical stimulation resulted in a significant upregulation of Cx43 (by approximately 1.5-fold in protein and by approximately 1.9-fold in messenger ribonucleic acid at 60 min). Immunoreactive signal of Cx43 was also increased. Angiotensin II (AngII) content was increased significantly by RES >15 min. Phosphorylated forms of extracellular signal-regulated protein kinase (ERK), c-Jun NH(2)-terminal kinases, and p38 mitogen-activated protein kinases (MAPKs) were all increased dramatically by RES with peaks at 5 - 60 min. Propagation of excitation was visualized by extracellular potential mapping by using a multiple electrode array system. Conduction velocity was increased significantly by RES for 60 to 90 min (25% - 27% increase). Treatment of myocytes with losartan (100 nmol/l) prevented most of these effects of RES; RES-induced upregulation of Cx43 was also prevented by specific inhibitors for ERK and p38 MAPKs. CONCLUSIONS: A short-term RES causes upregulation of Cx43 in cardiomyocytes and a concomitant increase of conduction velocity, mainly through an autocrine action of AngII to activate ERK and p38 MAPKs. 相似文献
100.
The interferon family stimulates the secretions of prolactin and interleukin-6 by the pituitary gland in vitro. 总被引:4,自引:0,他引:4
M Yamaguchi K Koike N Matsuzaki Y Yoshimoto T Taniguchi A Miyake O Tanizawa 《Journal of endocrinological investigation》1991,14(6):457-461
The effects of interferon-alpha, interferon-beta 1 and interferon-gamma on the secretions of prolactin (PRL) and interleukin-6 by primary cultured rat anterior pituitary cells were examined. These three interferons caused dose-dependent increases in PRL secretion within 30 min, and dose-dependent stimulation of interleukin-6 were weaker than the effects of interleukin-1 and tumor necrosis factor-alpha. These results suggest that interferons regulate PRL secretion from the pituitary gland, and that there may be a pathway in which interferons stimulate PRL secretion through interleukin-6 release. 相似文献