全文获取类型
收费全文 | 4375篇 |
免费 | 252篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 25篇 |
儿科学 | 164篇 |
妇产科学 | 81篇 |
基础医学 | 581篇 |
口腔科学 | 82篇 |
临床医学 | 403篇 |
内科学 | 1025篇 |
皮肤病学 | 231篇 |
神经病学 | 222篇 |
特种医学 | 141篇 |
外科学 | 568篇 |
综合类 | 13篇 |
一般理论 | 1篇 |
预防医学 | 168篇 |
眼科学 | 106篇 |
药学 | 423篇 |
中国医学 | 8篇 |
肿瘤学 | 409篇 |
出版年
2024年 | 5篇 |
2023年 | 20篇 |
2022年 | 36篇 |
2021年 | 90篇 |
2020年 | 65篇 |
2019年 | 102篇 |
2018年 | 102篇 |
2017年 | 74篇 |
2016年 | 109篇 |
2015年 | 108篇 |
2014年 | 112篇 |
2013年 | 163篇 |
2012年 | 248篇 |
2011年 | 305篇 |
2010年 | 188篇 |
2009年 | 138篇 |
2008年 | 268篇 |
2007年 | 279篇 |
2006年 | 271篇 |
2005年 | 275篇 |
2004年 | 257篇 |
2003年 | 236篇 |
2002年 | 248篇 |
2001年 | 107篇 |
2000年 | 104篇 |
1999年 | 108篇 |
1998年 | 44篇 |
1997年 | 42篇 |
1996年 | 47篇 |
1995年 | 33篇 |
1994年 | 38篇 |
1993年 | 21篇 |
1992年 | 50篇 |
1991年 | 49篇 |
1990年 | 36篇 |
1989年 | 50篇 |
1988年 | 34篇 |
1987年 | 31篇 |
1986年 | 20篇 |
1985年 | 17篇 |
1984年 | 16篇 |
1983年 | 16篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1979年 | 10篇 |
1978年 | 9篇 |
1977年 | 8篇 |
1972年 | 6篇 |
1970年 | 7篇 |
1966年 | 5篇 |
排序方式: 共有4651条查询结果,搜索用时 26 毫秒
21.
M E Myles C Alack P M Manino E R Reish S Higaki K Maruyama A Mallakin A Azcuy S Barker F A Ragan H Thompson James M Hill 《Journal of ocular pharmacology and therapeutics》2003,19(2):121-133
The identification of factors involved in herpes virus latency and reactivation is critical to a better understanding of the mechanisms essential to viral neuroinvasiveness and neurovirulence. Recurrent episodes of ocular herpes infections cause irreversible corneal scarring and are the primary cause of loss of vision due to an infectious agent in industrialized countries. In this study, we examined the ability of nicotine, a compound known to be involved in stress-associated immunomodulation and recognized as one of the most frequently used addictive agents, to induce ocular shedding in rabbits latently infected with herpes simplex virus type 1 (HSV-1) strain McKrae. New Zealand white rabbits latently infected with HSV-1 at 3-4 weeks post-inoculation were randomly divided into two groups. The corneas of all rabbits were free of lesions as verified by slit lamp biomicroscopy. One group received nicotine by transdermal patch (21 mg/day) for 20 days and the other group served as the control. Reactivation data were obtained by detection of virus in tear film collected by ocular swabbing performed concurrently with the administration of nicotine. Compilation of data from three separate experiments demonstrated that 16.5% (258/1560) of the swabs taken from rabbits treated with nicotine were positive for virus, compared with 8.3% (53/639) of swabs taken from controls. Rabbits receiving nicotine exhibited a significantly (P < 0.0001) higher rate of ocular shedding than controls. The concentration of nicotine in the serum was determined at various times (0-24 hrs) after new patch replacement. Peak (average) serum level of nicotine was obtained 8 hours after patch replacement and exhibited a broad range of values (0.233 microg/mL-6.21 microg/mL). These results suggest that an initial systemic exposure to nicotine significantly increases HSV-1 reactivation. Further studies are needed to reveal any effects of nicotine dependency and nicotine withdrawal on herpesvirus reactivation. 相似文献
22.
Synchronous pulmonary atypical adenomatous hyperplasia and metastatic osteosarcoma in a young female
Ken Kodama Masahiko Higashiyama Koji Takami Naozumi Higaki Kazuyuki Oda Nobuhito Araki 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(7):357-359
A 17-year-old female underwent metastasectomy of three synchronous lesions in the bilateral lungs under the diagnosis of metastatic
osteosarcoma, however, one of them was found to be atypical adenomatous hyperplasia (AAH). Since AAH is very rare among young
people, a careful evaluation of high-resolution computed tomographic image is important in determining the operative indications
and procedures in patients with multiple metastatic tumors. 相似文献
23.
24.
M Kawata K Higaki S Sekiya H Takamizawa T Muramatsu K Okumura 《Clinical and experimental immunology》1983,51(2):401-406
Antibodies reactive with a murine teratocarcinoma cell line (F9) were detected by immunofluorescence staining in sera from patients bearing ovarian germ cell tumour. Immunochemical studies revealed that antibodies binding to the cell surface of F9 cells react with large glycopeptides which are known to be components of F9 antigens defined by murine anti-F9 antibodies. In addition, treatment of F9 cells with retinoic acid, which induces differentiation of embryonal carcinoma cells, distinctly reduced both the ability of these antibodies to stain F9 cells and the biosynthesis of large glycopeptides by the cells. These findings indicate that the large glycopeptides precipitable by the patients' antibodies are differentiation associated antigens on characteristic embryonic cells. 相似文献
25.
Aoyama K Ozaki Y Nakanishi T Ogasawara MS Ikuta K Aoki K Blomgren K Suzumori K 《American journal of reproductive immunology (New York, N.Y. : 1989)》2004,52(6):362-369
PROBLEM: The distribution and activation of mu-calpain and possible cleavage of integrin in human endometrial cells under hypoxic condition were investigated. METHOD OF STUDY: Human endometrial epithelial and stromal cells were subjected to hypoxia, and subsequently used for immunostaining and western blot analysis. RESULTS: The proform of mu-calpain was detected in the cytoplasm of normal cells, and displayed a substantial decrease after hypoxia. Conversely, the active form of mu-calpain was not detected in normal cells, but was abundant after hypoxia. The cytoplasmic domain of integrin beta3 was also detected in the cytoplasm of endometrial cells. Western blot analysis confirmed that both the proform of mu-calpain and the integrin beta3 cytoplasmic domain decreased during hypoxia. CONCLUSIONS: Mu-calpain is activated in human endometrial cells during hypoxia and that subsequent cleavage of the integrin beta3 cytoplasmic domain may give some adverse effects to the function of human endometrium. 相似文献
26.
Regulation of IgE receptor expression on human peripheral blood lymphocytes by lymphocytosis promoting factor (LPF), lectins and dexamethasone.
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
K M Kim M Tanaka T Yoshimura K Katamura M Mayumi H Mikawa 《Clinical and experimental immunology》1987,68(2):418-426
Using a monoclonal anti-human Fc epsilon R antibody (H107), we found that lymphocytosis promoting factor (LPF), phytohaemagglutinin (PHA-P) and Concanavalin A (Con A) could induce Fc epsilon R, detected by immunofluorescence study, on normal human peripheral blood lymphocytes without IgE. The number of Fc epsilon R bearing lymphocytes was increased by stimulation with 3, 10 and 10 micrograms/ml of LPF, PHA-P and Con A, respectively, from 6.0 +/- 3.0/1000 cells to 26.0 +/- 7.9, 54.0 +/- 6.7 and 24.8 +/- 7.1/1000 cells, respectively. Although the induction of Fc epsilon R occurred neither in the separated T-enriched fraction (TEF) nor the T-depleted fraction (TDF), it recovered when the two fractions were mixed. The cell free supernatants from TEF stimulated with LPF or PHA-P could increase Fc epsilon R(+) cells in TDF, whereas those from TDF failed to increase them in TEF. The results suggest that the induction of Fc epsilon R occurs mainly on B lymphocytes by the soluble factor(s) formed by T cells stimulated with LPF or PHA-P. The induction of Fc epsilon R by stimulants was completely inhibited by 10(-6) M dexamethasone. It was demonstrated that the effects of dexamethasone on lymphocytes were dual: one was on B cells to inhibit responsive increases of Fc epsilon R, and the other was on T cells to suppress the formation of the soluble factor(s) which induced Fc epsilon R on B cells. 相似文献
27.
H Kanagawa E Takai F Tsuda A Machida M Kojima A Ishijima T Tanaka H Okamoto Y Miyakawa M Mayumi 《Journal of medical virology》1992,37(4):288-293
Of sera from 1,878 Japanese blood donors who carried hepatitis B surface antigen (HBsAg), 420 were subtyped as adw (22.4%) and 1,443 as adr (76.8%); only 15 (0.8%) contained HBsAg of subtype ayw or ayr. Sera with HBsAg/adr had higher HBsAg titres than those with HBsAg/adw (geometric mean of haemagglutination titre: 10.1 +/- 2.4 vs. 9.7 +/- 2.4, p less than 0.01), and a higher prevalence of hepatitis B e antigen (24% vs. 13%, p less than 0.001). Carriers of HBsAg/adr progressively predominated over those of HBsAg/adw with increasing age. Of sera from 1,863 carriers of HBsAg/adw or HBsAg/adr, 182 (9.8%) contained HBsAg particles with both subtypic determinants in the w/r allele. The presence of w and r determinants on the same particles was ascertained by sandwiching them between monoclonal antibody with the specificity for w and that with the specificity for r. HBsAg particles of compound subtype (adwr) were found more often in sera with hepatitis B e antigen than those without it (145/403 [36.0%] vs. 37/1,460 [2.5%], p less than 0.001). Sera with HBsAg/adwr particles had HBsAg titres higher than those without them (12.4 +/- 1.9 vs. 9.7 +/- 2.3, p less than 0.001). HBsAg/adwr particles arise from phenotypic mixing of the S-gene product of wild-type virus and that of mutants with point mutations for subtypic changes. The results obtained indicated that HBV strains of subtype adr have a higher replicative activity than those of adw, and suggested that mutations in the S gene for subtypic changes would be associated with an active replication of hepatitis B virus. 相似文献
28.
Naoki Utoguchi Tetsushi Nakata Hsien Hung Cheng Kenji Ikeda Hiroo Makimoto Yu Mu Shinsaku Nakagawa Motomasa Kobayashi Isao Kitagawa Tadanori Mayumi 《Inflammation》1997,21(2):223-233
Leukocyte adhesion to vascular endothelial cells is an essential step in the development of inflammatory diseases. We have searched for inhibitors of leukocyte-endothelial cell adhesion that could be used as anti-inflammatory drugs and found that bruceine B (0.2 g/ml; 0.44 M) inhibited human neutrophil or T cell adhesion to tumor necrosis factor- (TNF) stimulated human umbilical vein endothelial cells (HUVEC). The inhibition of neutrophil adhesion to TNF-stimulated HUVEC by bruceine B was not derived from cytotoxic effects, as determined by measurement of the level of lactate dehydrogenase (LDH) activity in conditioned medium. The effect of bruceine B on neutrophil adhesion to HUVEC was not seen when the neutrophils were preincubated with bruceine B. However, inhibitory effects were evident when the HUVEC were preincubated with bruceine B. Bruceine B also inhibited neutrophil adhesion to lipopolysaccharide-stimulated HUVEC and T cell adhesion to TNF-stimulated HUVEC. These findings suggest that bruceine B may have anti-inflammatory activity. 相似文献
29.
30.
D2-40 antibody immunoreactivity in developing human brain, brain tumors and cultured neural cells. 总被引:1,自引:0,他引:1
Yasuhiro Nakamura Yonehiro Kanemura Tomiko Yamada Yasuo Sugita Koichi Higaki Munehiko Yamamoto Mitsuhiko Takahashi Mami Yamasaki 《Modern pathology》2006,19(7):974-985
D2-40 antibody is raised against an oncofetal antigen, the M2A antigen. It has been used as a marker for lymphatic endothelium as well as mesothelioma and cerebellar hemangioblastoma. We demonstrate here that positive D2-40 immunoreactivity was found in the developing cerebrum, particularly in the germinal matrix layer, immature ependyma, choroid plexus and meninges. In the developing cerebellum, positive D2-40 immunoreactivity was found in the external granular layer particularly of the outer portion and the Purkinje cell layer as well as meninges. Some brain tumors such as anaplastic ependymoma, some medulloblastomas, glioblastoma, pineal germinoma, craniopharyngioma, choroid plexus papilloma, choroid plexus carcinoma, and meningioma showed positive immunoreactivity with D2-40. Therefore, D2-40 antibody is considered a useful marker for research on developing brain and diagnosis of brain tumors, differentiation between choroid plexus carcinoma and metastatic carcinoma. In addition, on cultured human neural cells, D2-40 immunoreactivity was found in nestin-positive neural stem/progenitor cells and neuronal lineage cells. As D2-40 antibody recognizes cell surface antigen M2A, it might be a candidate cell surface marker for isolation of human neural stem cells/neuronal lineage cells in the fluorescence-activated cell sorting technique. 相似文献