全文获取类型
收费全文 | 4164篇 |
免费 | 254篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 130篇 |
妇产科学 | 42篇 |
基础医学 | 532篇 |
口腔科学 | 87篇 |
临床医学 | 294篇 |
内科学 | 1051篇 |
皮肤病学 | 72篇 |
神经病学 | 405篇 |
特种医学 | 127篇 |
外科学 | 621篇 |
综合类 | 33篇 |
预防医学 | 139篇 |
眼科学 | 44篇 |
药学 | 340篇 |
肿瘤学 | 494篇 |
出版年
2023年 | 16篇 |
2022年 | 45篇 |
2021年 | 68篇 |
2020年 | 35篇 |
2019年 | 49篇 |
2018年 | 58篇 |
2017年 | 47篇 |
2016年 | 54篇 |
2015年 | 53篇 |
2014年 | 52篇 |
2013年 | 87篇 |
2012年 | 141篇 |
2011年 | 191篇 |
2010年 | 94篇 |
2009年 | 80篇 |
2008年 | 163篇 |
2007年 | 152篇 |
2006年 | 172篇 |
2005年 | 184篇 |
2004年 | 190篇 |
2003年 | 174篇 |
2002年 | 189篇 |
2001年 | 151篇 |
2000年 | 152篇 |
1999年 | 165篇 |
1998年 | 66篇 |
1997年 | 50篇 |
1996年 | 37篇 |
1995年 | 40篇 |
1994年 | 23篇 |
1993年 | 32篇 |
1992年 | 130篇 |
1991年 | 130篇 |
1990年 | 135篇 |
1989年 | 141篇 |
1988年 | 152篇 |
1987年 | 96篇 |
1986年 | 88篇 |
1985年 | 80篇 |
1984年 | 74篇 |
1983年 | 42篇 |
1979年 | 59篇 |
1978年 | 27篇 |
1977年 | 36篇 |
1976年 | 22篇 |
1975年 | 20篇 |
1974年 | 17篇 |
1973年 | 21篇 |
1972年 | 20篇 |
1971年 | 19篇 |
排序方式: 共有4425条查询结果,搜索用时 15 毫秒
51.
Monoclonal antibodies against synthesized short peptides corresponding to human AA amyloid protein 总被引:1,自引:0,他引:1
T Yokota T Ishihara M Takahashi Y Yamashita H Kawano Y Fujinaga F Uchino N Hanai H Yoshida S Honda 《Acta pathologica japonica》1987,37(7):1135-1142
Monoclonal antibodies (McAbs) were raised against the synthesized short peptides corresponding to 37-47 residues in amino acid sequence of human AA protein. The McAbs reacted immunohistochemically to amyloid tissues from cow, mouse, swan, and human AA amyloidosis. We concluded that the McAbs were useful for identification of AA type amyloidosis of various species, and that the 37-47 residues were effective antigenic sites in AA protein. 相似文献
52.
Monocarboxylate transporter 1 (MCT1) plays a direct role in short-chain fatty acids absorption in caprine rumen 总被引:2,自引:0,他引:2
Doaa Kirat Junji Masuoka Hideaki Hayashi Hidetomo Iwano Hiroshi Yokota Hiroyuki Taniyama Seiyu Kato 《The Journal of physiology》2006,576(2):635-647
Despite the importance of short-chain fatty acids (SCFA) in maintaining the ruminant physiology, the mechanism of SCFA absorption is still not fully studied. The goal of this study was to elucidate the possible involvement of monocarboxylate transporter 1 (MCT1) in the mechanism of SCFA transport in the caprine rumen, and to delineate the precise cellular localization and the level of MCT1 protein along the entire caprine gastrointestinal tract. RT-PCR revealed the presence of mRNA encoding for MCT1 in all regions of the caprine gastrointestinal tract. Quantitative Western blot analysis showed that the level of MCT1 protein was in the order of rumen ≥ reticulum > omasum > caecum > proximal colon > distal colon > abomasum > small intestine. Immunohistochemistry and immunofluorescence confocal analyses revealed widespread immunoreactive positivities for MCT1 in the caprine stomach and large intestine. Amongst the stratified squamous epithelial cells of the forestomach, MCT1 was predominantly expressed on the cell boundaries of the stratum basale and stratum spinosum. Double-immunofluorescence confocal laser-scanning microscopy confirmed the co-localization of MCT1 with its ancillary protein, CD147 in the caprine gastrointestinal tract. In vivo and in vitro functional studies, under the influence of the MCT1 inhibitors, p -chloromercuribenzoate (pCMB) and p -chloromercuribenzoic acid (pCMBA), demonstrated significant inhibitory effect on acetate and propionate transport in the rumen. This study provides evidence, for the first time in ruminants, that MCT1 has a direct role in the transepithelial transport and efflux of the SCFA across the stratum spinosum and stratum basale of the forestomach toward the blood side. 相似文献
53.
Two regions of homozygous deletion clusters at chromosome band 9p21 in human lung cancer 总被引:5,自引:0,他引:5
Hamada K Kohno T Takahashi M Yamazaki M Yamazaki M Tashiro H Sugawara C Ohwada S Sekido Y Minna JD Yokota J 《Genes, chromosomes & cancer》2000,27(3):308-318
We examined 149 lung cancer cell lines for homozygous deletions using 24 DNA markers, which were mapped and ordered in chromosome band 9p21, to define the target regions for 9p21 deletions in human lung cancer. Homozygous deletions were detected in 39 (26%) cell lines and clustered at 2 independent regions. One was the region containing the p16/CDKN2A tumor suppressor gene, and this region was deleted in 32 (21%) cell lines. The other was the region containing D9S171, which is the locus approximately 3 Mb proximal to the CDKN2A locus. This region, designated as the D9S171 region, was deleted in 18 (12%) cell lines. Seven of the 18 cell lines had identical minimum deletions of a 17,036 bp sequence located 20 kb distal to the D9S171 locus. However, such a deletion was also observed in the corresponding B-lymphoblastoid cell line from 1 of the 7 cell lines and in 5 (16%) of 32 noncancerous tissues, suggesting that the deletion was a genetic polymorphism. By considering this polymorphism, 11 (7%) cell lines still had deletions at the D9S171 region. Two NSCLC cell lines showed deletions at the D9S171 region and retentions of the CDKN2A locus. Furthermore, an NSCLC cell line showed discontinuous deletions including either the CDKN2A or D9S171 locus. Therefore, the region surrounding the D9S171 locus was defined as another target region for the 9p21 deletions. It is possible that unknown tumor suppressor gene(s) are present in this chromosomal region. Genes Chromosomes Cancer 27:308-318, 2000. 相似文献
54.
Protective effect of human granulocyte colony-stimulating factor on microbial infection in neutropenic mice. 总被引:6,自引:8,他引:6 下载免费PDF全文
M Matsumoto S Matsubara T Matsuno M Tamura K Hattori H Nomura M Ono T Yokota 《Infection and immunity》1987,55(11):2715-2720
A purified human granulocyte colony-stimulating factor (hG-CSF) was studied for its protective effect on the induction of neutropenia and enhanced susceptibility to microbial infections in mice receiving cyclophosphamide (CPA). A severe reduction in peripheral blood neutrophils was induced 4 days after injection with 200 mg of CPA per kg although the level normalized rapidly thereafter. When mice were injected subcutaneously once a day with 2.5 micrograms of hG-CSF beginning on the day after CPA injection, the reduction was prevented markedly, even 4 days later. On the other hand, in mice receiving CPA 4 days prior to infection, a weakened resistance to intraperitoneal challenge with a strain of Pseudomonas aeruginosa was induced. This weakened resistance was dose-dependently restored to normal by four daily injections with hG-CSF. A daily dose of 1.0 microgram was required for complete restoration, although hG-CSF did not directly inhibit bacterial growth in vitro. In hG-CSF-treated mice, morphologically mature neutrophils migrated rapidly into the peritoneal cavities where bacteria were inoculated, followed by a rapid elimination of bacteria from the locality as compared with controls. In addition, the same treatment with hG-CSF was able to protect significantly against systemic infections caused by Serratia marcescens, Escherichia coli, Staphylococcus aureus, and Candida albicans. These data show the possibility that prophylactic therapy with hG-CSF may augment the resistance of immunocompromised patients to infections. 相似文献
55.
Yoshida T Iwamoto T Adachi K Yokota T Miyake Y Hamaguchi M 《International journal of molecular medicine》2005,15(2):269-275
M1 mouse myeloid leukemia cells exhibit growth arrest and differentiation to monocytes/macrophages in response to leukemia inhibitory factor (LIF) stimulation. Although recent studies have demonstrated that STAT3 plays a central role in this process, it is unknown whether STAT3 activation alone is sufficient. To address this issue, we have established M1/STAT3ER cells, where STAT3 is selectively activated by 4-hydroxytamoxifen (4HT). 4HT stimulation did not have any effect on growth and morphology of M1/ STAT3ER cells, and did not induce the down-regulation of mRNA of c-myc and c-myb, which is necessary for M1 cell differentiation. On the other hand, mRNA of jun-B, IRF1 and p19 was increased by 4HT. DNA precipitation assay indicated that both stimulation of LIF and 4HT similarly activated STAT3ER. Introduction of a constitutive active MAP kinase kinase (MEK1) into M1/STAT3ER cells did not induce differentiation either. Together, our present data suggest that signaling other than the activation of STAT3 and MEK1 may be necessary for M1 cell-growth arrest and differentiation, while a set of early genes of LIF are induced by only STAT3 activation. 相似文献
56.
57.
M Hayashi C Abe R T Nozawa T Yokota T Iso Y Shiokawa 《International journal of immunopharmacology》1986,8(3):299-304
Macrophages which play an important role in host resistance against infections are considered to be a target for various immunomodulators. In order to examine the effects of selected immunomodulators on macrophage function, the effects of N-(2-mercapto-2-methylpropanoyl)-L-cysteine (SA96), levamisole (LMS) and D-penicillamine (D-Pc) on the candidacidal activity of the normal peritoneal cells (PC) were investigated. In the in vitro studies, SA96 increased the candidacidal activity of PC 4-fold, while D-Pc and LMS treatments did not increase this activity. In the ex vivo studies, PC obtained from the mice pre-treated with SA96, D-Pc and LMS showed a high candidacidal activity. Elevated candidacidal activity was not due to changes of cell types of PC populations. These results suggest that D-Pc and LMS activate the function of macrophage in vivo and SA96 activates the function both in vitro and in vivo. 相似文献
58.
Tokuhiro Ishihara Yoshimi Yamashita Yoshiko Okuzono Tadaaki Yokota Mutsuo Takahashi Toshiaki Kamei Fumiya Uchino Noboru Matsumoto Shiro Miwa Hisaichi Fuji Takeshi Kozaki 《Ultrastructural pathology》1985,8(1):13-23
By light and electron microscopy, we observed foamy cells in the spleens from a patient with hemolytic anemia due to red cell adenosine deaminase (ADA) overproduction, a patient with rheumatoid arthritis (RA) treated with gold, and patients with idiopathic thrombocytopenic purpura (ITP)
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
59.
Tadaaki Yokota Yoshimi Yamashita Yoshiko Okuzono Mutsuo Takahashi Shigeyoshi Fujihara Shin'ichiro Akizuki Tokuhiro Ishihara Fumiya Uchino Takako Iwata 《Pathology international》1984,34(3):663-668
A case of malignant cystosarcoma phyllodes of the prostate is reported in a 45-year-old male. This tumor was composed of benign columnar or squamous cystic folds and sarcomatous stroma including rhabdomyomatous elements. The prostatic origin of the tumor was clearly proved by the unlabeled immunoperoxidase method. ACTA PATHOL. JPN. 34: 663–668, 1984. 相似文献
60.
Tissue factor pathway inhibitor can interact with platelets 总被引:3,自引:0,他引:3
Nishioka T Yokota M Hino M Tsuda I Tatsumi N 《Journal of immunological methods》2002,266(1-2):181-184
Tissue factor pathway inhibitor (TFPI) regulates the extrinsic pathway of blood coagulation. However, there is no report on interaction between TFPI and platelets other than that by Tsuji, who found that whole blood anticoagulated with TFPI exhibited remarkable decrease in platelet count. Our study revealed that washed platelets suspended in modified Tyrode's buffer (8 mM CaCl2) containing TFPI exhibit platelet aggregation. However, platelets aggregation was observed without TFPI, but its increase and intensity were slow and weak, compared to that in the presence of TFPI. This aggregation was inhibited by anti-CD41 (anti-GPIIb) antibody. This finding suggested that TFPI promotes platelet aggregation. 相似文献