全文获取类型
收费全文 | 21112篇 |
免费 | 1408篇 |
国内免费 | 158篇 |
专业分类
耳鼻咽喉 | 356篇 |
儿科学 | 354篇 |
妇产科学 | 409篇 |
基础医学 | 2810篇 |
口腔科学 | 511篇 |
临床医学 | 1899篇 |
内科学 | 4386篇 |
皮肤病学 | 595篇 |
神经病学 | 1352篇 |
特种医学 | 1135篇 |
外科学 | 2771篇 |
综合类 | 779篇 |
现状与发展 | 1篇 |
一般理论 | 14篇 |
预防医学 | 1084篇 |
眼科学 | 724篇 |
药学 | 1623篇 |
中国医学 | 170篇 |
肿瘤学 | 1705篇 |
出版年
2023年 | 204篇 |
2022年 | 435篇 |
2021年 | 774篇 |
2020年 | 445篇 |
2019年 | 548篇 |
2018年 | 708篇 |
2017年 | 514篇 |
2016年 | 623篇 |
2015年 | 822篇 |
2014年 | 1006篇 |
2013年 | 1076篇 |
2012年 | 1713篇 |
2011年 | 1661篇 |
2010年 | 930篇 |
2009年 | 835篇 |
2008年 | 1174篇 |
2007年 | 1150篇 |
2006年 | 1123篇 |
2005年 | 1065篇 |
2004年 | 840篇 |
2003年 | 691篇 |
2002年 | 568篇 |
2001年 | 526篇 |
2000年 | 512篇 |
1999年 | 406篇 |
1998年 | 132篇 |
1997年 | 110篇 |
1996年 | 76篇 |
1995年 | 86篇 |
1994年 | 82篇 |
1993年 | 64篇 |
1992年 | 155篇 |
1991年 | 167篇 |
1990年 | 137篇 |
1989年 | 130篇 |
1988年 | 116篇 |
1987年 | 133篇 |
1986年 | 106篇 |
1985年 | 94篇 |
1984年 | 73篇 |
1983年 | 69篇 |
1982年 | 36篇 |
1979年 | 60篇 |
1977年 | 39篇 |
1975年 | 38篇 |
1974年 | 39篇 |
1973年 | 36篇 |
1972年 | 37篇 |
1970年 | 35篇 |
1969年 | 40篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
HLA and Thyrotoxicosis (Graves' Disease) in Chinese 总被引:1,自引:0,他引:1
S. H. Chan P. P. B. Yeo K. F. Lui G. B. Wee K. T. Woo P. Lim J. S. Cheah 《Tissue antigens》1978,12(2):109-114
HLA locus A and B typing was performed on 86 Chinese thyrotoxicosis (Graves' Disease) patients and 238 normal Chinese subjects. The frequency of HLA-Bw46 (Sin 2) was found to be significantly higher among the patients than controls (X2 = 26.15, corrected P <.003, relative risk = 3.74). The risk associated with Bw46 was reflected in the Bw46 heterozygotes. The relative risks of the joint occurrence of Bw46/B40 and Bw46/B13 were 8.74 and 5.88 respectively. 相似文献
42.
Galactosylated PVDF membrane promotes hepatocyte attachment and functional maintenance 总被引:2,自引:0,他引:2
Lu HF Lim WS Wang J Tang ZQ Zhang PC Leong KW Chia SM Yu H Mao HQ 《Biomaterials》2003,24(27):4893-4903
One of the major challenges in BLAD design is to develop functional substrates suitable for hepatocyte attachment and functional maintenance. In the present study, we designed a poly(vinylidene difluoride) (PVDF) surface coated with galactose-tethered Pluronic polymer. The galactose-derived Pluronic F68 (F68-Gal) was adsorbed on PVDF membrane through hydrophobic-hydrophobic interaction between PVDF and the polypropylene oxide segment in Pluronic. The galactose density on the modified PVDF surface increased with the concentration of the F68-Gal solution, reaching 15.4 nmol galactosyl groups per cm2 when a 1 mg/ml of F68-Gal solution was used. The adsorbed F68-Gal remained relatively stable in culture medium. Rat hepatocytes attachment efficiency on F68-Gal modified PVDF membrane was similar to that on collagen-coated surface. The attached hepatocytes on PVDF/F68-Gal membrane self-assembled into multi-cellular spheroids after 1 day of culture. These attached hepatocytes in spheroids exhibited higher cell functions such as albumin synthesis and P450 1A1 detoxification function compared to unmodified PVDF membrane and collagen-coated surface. These results suggest the potential of this galactose-immobilized PVDF membrane as a suitable substrate for hepatocyte culture. 相似文献
43.
Lim DJ Rubenstein AE Evans DG Jacks T Seizinger BG Baser ME Beebe D Brackmann DE Chiocca EA Fehon RG Giovannini M Glazer R Gusella JF Gutmann DH Korf B Lieberman F Martuza R McClatchey AI Parry DM Pulst SM Ramesh V Ramsey WJ Ratner N Rutkowski JL Ruttledge M Weinstein DE 《Journal of neurogenetics》2000,14(2):63-106
44.
45.
Thomas Hoffman Anil K. Tripathi Young Lim Lee Elaine F. Lizzio Ezio Bonvini 《Inflammation》1992,16(6):571-585
Human monocytes released superoxide anion, prostaglandin E2, leukotriene B4, IL-1, and TNF when exposed to plastic surfaces coated with murine anti-CD3 monoclonal antibody, OKT 3. Stimulation of mediator release by OKT 3 was dependent on the amount of antibody immobilized onto wells of plastic tissue culture plates. Soluble antibody or antibody adsorbed to monocytes and reacted with an aggregating (cross-linking) second antibody failed to induce mediator release. Monocytes armed with OKT 3 formed rosettes with T cells in a fashion indistinguishable from that seen between monocytes and T cells sensitized with OKT 3. Monocytes with adsorbed OKT 3 antibodies released IL-1 and TNF- when exposed to unsensitized T cells, although increased superoxide release could not be detected. OKT 4a, a murine IgG2a antibody that reacts with a different T cell epitope (CD4), failed to induce cytokine release from monocytes when cross-linked by T cells or a CD4+ T cell line, even in the presence of IL-2 or IFN-. These data indicate that certain antibodies bound to Fc receptors (FcR) of monocytes may trigger monocyte function when reacting with cells bearing the appropriate target antigens. FcR-mediated signaling resulting in mediator release may be involved in initiating or regulating the immune response. Furthermore, systemically administered monoclonal antibodies may induce inflammatory responses and their attendant symptomatologies via their interaction with FcR-bearing inflammatory cells. 相似文献
46.
Syndrome of partial aniridia, cerebellar ataxia, and mental retardation--Gillespie syndrome 总被引:2,自引:0,他引:2
Here we describe a 5-year-old girl with Gillespie syndrome of cerebellar ataxia, partial aniridia, and mental retardation. The Gillespie syndrome probably is an autosomal recessive trait. 相似文献
47.
Amanita virosa induced toxic hepatitis: report of three cases 总被引:1,自引:0,他引:1
We report here three cases of Amanita virosa induced toxic hepatitis. Two of the three cases recovered but the other died 10 days after mushroom ingestion. Since the mortality of Amanita mushroom induced toxic hepatitis is very high, prompt diagnosis and aggressive therapeutic measures should be initiated as soon as possible. Our cases showed that the initial serum aminotransferase levels might not predict the clinical outcome of the patient, but that the prothrombin time (PT) seemed to be a more useful prognostic marker. Close monitoring of aminotransferase levels and PT as well as appropriate therapy are recommended. All three cases showed signs of proteinuria and we were able to characterize mixed tubular and glomerular type proteinuria at 3 or 4 days after ingestion in two cases. Among the previously reported Korean cases of suspected Amanita induced toxic hepatitis, most species could not be identified except for four cases of Amanita virosa. No cases of Amanita phalloides induced toxic hepatitis have been identified in Korea so far. 相似文献
48.
Mammalian transforming growth factor beta1 activated after ingestion by Anopheles stephensi modulates mosquito immunity 下载免费PDF全文
Luckhart S Crampton AL Zamora R Lieber MJ Dos Santos PC Peterson TM Emmith N Lim J Wink DA Vodovotz Y 《Infection and immunity》2003,71(6):3000-3009
During the process of bloodfeeding by Anopheles stephensi, mammalian latent transforming growth factor beta1 (TGF-beta1) is ingested and activated rapidly in the mosquito midgut. Activation may involve heme and nitric oxide (NO), agents released in the midgut during blood digestion and catalysis of L-arginine oxidation by A. stephensi NO synthase (AsNOS). Active TGF-beta1 persists in the mosquito midgut to extended times postingestion and is recognized by mosquito cells as a cytokine. In a manner analogous to the regulation of vertebrate inducible NO synthase and malaria parasite (Plasmodium) infection in mammals by TGF-beta1, TGF-beta1 regulates AsNOS expression and Plasmodium development in A. stephensi. Together, these observations indicate that, through conserved immunological cross talk, mammalian and mosquito immune systems interface with each other to influence the cycle of Plasmodium development. 相似文献
49.
Moo -Yeol Lee Hyo -Weon Bang In -Ja Lim Dae -Yong Uhm Sang -Don Rhee 《Pflügers Archiv : European journal of physiology》1994,429(1):150-152
Large conductance Ca2+-activated K+ channel was identified and studied in excised inside-out membrane patches of freshly dispersed smooth muscle cells from rabbit
gastric antrum. The current-voltage relationship of the single channel was linear from -80 to +80 mV of pipette voltage in
which single channel conductance was 249±17.8 pS (n=19) in symmetrical concentration of K+ (145mM) across the patch. Activity of the channel (NPo) depended not only on cytoplasmic calcium concentration but also on
membrane potential. MgATP increased NPo in a dose-dependent manner and Mg2+ was prerequisite for the effect. Okadaic acid (l00nM), inhibitor of protein phosphatases, increased NPo further in the presence
of MgATP. Therefore, it would be concluded that activity of the calcium-activated K+ channel in gastric smooth muscle cells was controlled by phosphorylation state of the channel protein and the state is further
modulated by membrane-delimited protein kinase and protein phosphatase activities. 相似文献
50.