全文获取类型
收费全文 | 15168篇 |
免费 | 732篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 135篇 |
儿科学 | 410篇 |
妇产科学 | 187篇 |
基础医学 | 1918篇 |
口腔科学 | 431篇 |
临床医学 | 1114篇 |
内科学 | 3600篇 |
皮肤病学 | 186篇 |
神经病学 | 1056篇 |
特种医学 | 673篇 |
外科学 | 3242篇 |
综合类 | 66篇 |
一般理论 | 1篇 |
预防医学 | 470篇 |
眼科学 | 357篇 |
药学 | 866篇 |
中国医学 | 22篇 |
肿瘤学 | 1246篇 |
出版年
2023年 | 90篇 |
2022年 | 222篇 |
2021年 | 353篇 |
2020年 | 192篇 |
2019年 | 229篇 |
2018年 | 271篇 |
2017年 | 233篇 |
2016年 | 231篇 |
2015年 | 266篇 |
2014年 | 333篇 |
2013年 | 441篇 |
2012年 | 721篇 |
2011年 | 693篇 |
2010年 | 400篇 |
2009年 | 318篇 |
2008年 | 544篇 |
2007年 | 664篇 |
2006年 | 621篇 |
2005年 | 641篇 |
2004年 | 593篇 |
2003年 | 631篇 |
2002年 | 595篇 |
2001年 | 527篇 |
2000年 | 554篇 |
1999年 | 484篇 |
1998年 | 258篇 |
1997年 | 155篇 |
1996年 | 166篇 |
1995年 | 116篇 |
1994年 | 122篇 |
1993年 | 112篇 |
1992年 | 347篇 |
1991年 | 353篇 |
1990年 | 314篇 |
1989年 | 322篇 |
1988年 | 307篇 |
1987年 | 307篇 |
1986年 | 277篇 |
1985年 | 264篇 |
1984年 | 158篇 |
1983年 | 166篇 |
1982年 | 80篇 |
1979年 | 144篇 |
1978年 | 80篇 |
1977年 | 90篇 |
1975年 | 93篇 |
1974年 | 92篇 |
1973年 | 108篇 |
1972年 | 91篇 |
1971年 | 81篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Takaaki Ohmori Kazuyo Okada Ryo Tabei Keisuke Sugiura Shinji Nabeshima Hiroji Ohoka Masaki Okamoto 《Pathology international》1994,44(4):333-337
A case of primary seminal vesicle carcinoma is reported. The tumor was a CA125-producing adenocarcinoma consisting of fine papillary-tubular, intricate branching or anastomosing glandular structures and was composed of small cuboidal, but occasionally hobnailed, cells with mostly clear, but occasionally granular, cytoplasm. Some tumor cells showed evidence of secretion of seromucinous materials into the interpapillary and cystic space. lmmunohistochemically, almost half of the tumor cells expressed a positive reaction with anti-CAl25, a common serological marker for ovarian epithelial carcinomas; however, no tumor cells expressed any other serological tumor markers such as carcinoem-bryonic antigen, α-fetoprotein, human chorionic gonadotropin, prostatic specific acid phosphatase, or prostatic specific antigen. The patient showed a high level of serological CA125, which fluctuated parallel with the growth, removal and recurrence of the tumor. The morphological and immunohistochemical findings suggested a close relationship between the present tumor and clear cell carcinoma of the ovary, which is thought to be of a Müllerian-Wolfian duct origin. 相似文献
62.
Akagi M Inui K Nakajima S Shima M Nishigaki T Muramatsu T Kokubu C Tsukamoto H Sakai N Okada S 《Journal of human genetics》2000,45(1):60-62
Fanconi-Bickel syndrome (FBS), or glycogen storage disease type XI, is a rare autosomal recessive disorder characterized
by hepatorenal glycogen accumulation, Fanconi nephropathy, and impaired utilization of glucose and galactose. Recently, this
disease was elucidated to link mutations in the glucose transporter 2 (GLUT2) gene. Only three mutations in three FBS families have been reported. Therefore, it is important to elucidate mutations in
the GLUT2 gene in FBS by answering the question of whether the syndrome is a single gene disease. In this report, we describe two patients
in two unrelated families clinically diagnosed with FBS. No mutation in the entire protein coding region of the GLUT2 gene was detected in patient 1, which suggested that no mutation existed in the GLUT 2 gene, or that some mutations had affected the expression of the GLUT 2 gene. In patient 2, a novel homozygous nonsense mutation (W420X, Trp at codon 420 to stop codon) was detected. These results
support the correlation between GLTU2 gene mutation and FBS syndrome. However, many patients must be analyzed to determine whether other genes are involved in
FBS.
Received: July 16, 1999 / Accepted: September 3, 1999 相似文献
63.
Kobayashi K Kusakabe M Okada M Sakairi T Goto K Tsuchiya T Sugimoto J Sano F Mutai M 《Toxicologic pathology》2000,28(5):664-667
Hepatocellular carcinomas (HCCs) were induced in male Fischer 344 rats with dietary 3'-methyl-4-(dimethylamino)-azobenzene treatment and were classified into solid, glandular (well- or poorly differentiated), and trabecular types. Investigation of cell proliferation kinetics and immunohistochemical localization of transforming growth factor alpha (TGF-alpha) demonstrated all solid (n = 24) and poorly differentiated glandular type (n = 6) HCCs to have TGF-alpha-positive nuclei. Nuclear staining of TGF-alpha was also observed in 13 of 28 (46%) trabecular-type HCCs, whereas 12 (43%) exhibited cytoplasmic staining, and 3 (11%) were negative. As for well-differentiated glandular HCCs, 7 of 20 (35%) were positively stained in their nucleus, another 7 (35%) demonstrated antibody binding in the cytoplasm, and 6 (30%) were negative. The order for growth rate evaluated by bromodeoxyuridine (BrdU) labeling was solid (38.22%), poorly differentiated glandular (26.82%), trabecular (7.98%), and well-differentiated glandular (2.57%) types. For trabecular HCCs with nuclear, cytoplasmic, or negative TGF reactions, values were 13.39% (n = 13), 3.61% (n = 12), and 2.01% (n = 3), respectively. Likewise, BrdU-labeling indices for the counterpart groups of well-differentiated glandular type HCCs were 4.53, 1.91, and 1.29%, respectively. The results indicate that TGF-alpha expression might be linked to histopathological differentiation and cell proliferation in rat HCCs. 相似文献
64.
65.
Intra and extracellular localization of alpha-fetoprotein (AFP) has been studied by an indirect peroxidase labeled antibody method using 12 cases of human hepatocellular carcinoma (HCC). With light microscopic observation, positive immuno-staining for AFP was observed in 6 out of 12 cases and demonstrated as granular or diffuse deposits in the cytoplasm of neoplastic hepatocytes. In electron microscopic studies, 8 cases showed the positive immuno-staining for AFP in the neoplastic hepatocytes. Intracellular antigen was well circumscribed within certain cell organelles with the positive immuno-staining for AFP being observed in perinuclear space, cisternae of rough endoplasmic reticulum (RER), Golgi complexes, and secretory vesicles. In addition, the positive immuno-staining for AFP was observed in bile canaliculus-like space in most cases with increased levels of serum AFP and in some cases which showed normal levels of serum AFP. Furthermore, the positive immuno-staining for AFP was also observed in intercellular, Disse's-like and sinusoid-like spaces, and micropinocytotic and lysosome-like vesicles in the endothelial cells in a few cases which showed excessively high value of serum AFP. ACTA PATHOL. JPN. 37:915–928, 1987. 相似文献
66.
Torii K Kimura H Li X Okada T Imura T Furusaki F Ono T Yoshida H 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(3):207-212
Chronic hypoxia has been newly proposed as a common mechanism of tubulointerstitial fibrosis in the progression of various chronic inflammatory renal diseases, where PAI-1 plays an important role in the accumulation of extracellular matrix (ECM) through inhibition of plasmin-dependent ECM degradation. In the present study, we investigated the presence of PAI-1 in renal tubular cells by immunostaining renal biopsy samples. We also closely examined the effects of hypoxia and TNF-alpha on PAI-1 expression in cultured human proximal renal tubular cells (HRCs). Confluent cells growth-arrested in DMEM for 24h were exposed to hypoxia (1% O2) and/or TNF-alpha at 10 ng/ml for 24 hours. Amounts of PAI-1 protein and mRNA after stimulation were measured by ELISA and TaqMan quantitative PCR, respectively and compared to those in cells incubated under control conditions (18% O2 without TNF-alpha). HIF-1alpha was demonstrated by immunoblot analysis. In crescentic glomerulonephritis, clusters of proximal tubules were specifically stained for PAI-1. Treatment of 24 hours with hypoxia, TNF-alpha and their combination induced a 2.7-fold, a 1.8-fold, and a 4.6-fold increase in PAI-1 protein secretion, and produced a 3.6-fold, a 3.3-fold, and a 12.1-fold increase at the PAI-1 mRNA level, respectively. Immunoblot analysis revealed that hypoxia-inducible factor-1alpha (HIF-1alpha) was markedly accumulated in the nuclear fraction after 16-hours exposure of HPTECs to hypoxia but not to TNF-alpha. In conclusion, hypoxia induces PAI-1 expression via remarkable nuclear accumulation of HIF-1alpha in HRCs. TNF-alpha can enhance this hypoxia-induced PAI-1 expression. 相似文献
67.
Comparison of the inhibitory effects of glucocorticoids on the expression of eotaxin in airway epithelial cell line BEAS-2B] 总被引:2,自引:0,他引:2
Koushi Ieki Satoshi Matsukura Fumio Kokubu Masatsugu Kurokawa Mio Kawaguchi Hideki Kuga Shin Watanabe Shintaro Suzuki Miho Odaka Hiroko Takeuchi Robert P Schleimer Mitsuru Adachi 《Arerugī》2004,53(4):423-429
OBJECTIVE: Inhaled corticosteroids play a pivotal role in the treatment of asthma. To observe the mechanisms of glucocorticoids, we focused our study on the comparison of several glucocorticoids' effects on eotaxin expression in the airway epithelial cells. METHODS: Airway epithelial cell line BEAS-2B was cultured in vitro. Cells were preincubated with or without glucocorticoids (becromethasone dipropionate; BDP, budesonide; BUD, fluticasone propionate; FP) and stimulated with TNFalpha and/or IL-4. Protein levels of eotaxin in the supernatants of the cultured cells were determined by ELISA. RESULTS AND CONCLUSIONS: TNFalpha and IL-4 increased the levels of eotaxin in BEAS-2B cells. Combination of these cytokines synergistically upregulated the eotaxin expression as reported previously. Each glucocorticoid significantly inhibited the expression of eotaxin protein induced with TNFalpha and IL-4 and the compared efficacy was in order of FP>BUD>BDP. FP seemed most potent and the inhibitory effect was also observed with relatively low concentration such as 10 (-10)M. Taken together, the comparison of the potency of each glucocorticoid using airway epithelial cells may reflect the efficacy of these drugs in asthmatics. 相似文献
68.
The critical role of ocular-infiltrating macrophages in the development of choroidal neovascularization 总被引:9,自引:0,他引:9
Tsutsumi C Sonoda KH Egashira K Qiao H Hisatomi T Nakao S Ishibashi M Charo IF Sakamoto T Murata T Ishibashi T 《Journal of leukocyte biology》2003,74(1):25-32
Choroidal neovascularization (CNV) is directly related to visual loss in some eye diseases, such as age-related macular degeneration. Although several human histological studies have suggested the participation of macrophages in CNV formation, the precise mechanisms are still not fully understood. In this study, we elucidated the role of ocular-infiltrating macrophages in experimental CNV using CCR2 knockout (KO) mice, wild-type mice, and C57BL/6 (B6) mice. CCR2 is the receptor of monocyte chemoattractant protein-1, and the number of infiltrating macrophage and the area of CNV were significantly reduced in CCR2 KO mice. Enriched ocular-infiltrating macrophages from B6 mice actually showed angiogenic ability in a dorsal air sac assay. Moreover, their expression of class II, CD40, B7-1 and B7-2 molecules, and the mRNA for potential angiogenic factors, such as vascular endothelial growth factor, basic fibroblast growth factor, and tumor necrosis factor alpha, was also observed. Collectively, we conclude that ocular-infiltrating macrophages play an important role in CNV generation. 相似文献
69.
70.
Shinohara T Okada M Suzuki K Ohsuzu F Katayama M 《Journal of immunoassay & immunochemistry》2005,26(3):189-202
We have newly established 3 distinct murine monoclonal antibodies (MoAbs) against human soluble elastin by using chemically denatured immunogen isolated from human aorta; they are designated as HASG-2, HASG-30, and HASG-61-1. All of these MoAbs were highly reactive with soluble forms of native elastin in normal human serum. HASG-2 and HASG-61-1 MoAbs can recognize soluble bovine elastin as well as human antigen, but HASG-30 cannot. The sandwich enzyme-linked immunosorbent assay (ELISA) for human soluble elastin was developed with HASG-61-1 labeled with peroxidase and HASG-30 immobilized on the microplates. The circulating levels of soluble elastin in human healthy subjects (mean +/- SD; 42.9 +/- 19.9ng/mL; n = 85) could be measured with full accuracy and reproducibility, and gradually increased with aging. The positive correlation between the levels and ages was statistically significant (r = 0.581, p < 0.0001). In addition, we could also determine the concentration of tropoelastin secreted from cultured human dermal fibroblasts accurately by this ELISA. This simple assay can be utilized for the routine clinical laboratory screening of patients with arteriosclerotic vascular diseases or to accurately determine the concentrations of tropoelastin secreted from cultured human cells. 相似文献