全文获取类型
收费全文 | 12794篇 |
免费 | 1256篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 167篇 |
儿科学 | 520篇 |
妇产科学 | 262篇 |
基础医学 | 1901篇 |
口腔科学 | 203篇 |
临床医学 | 1765篇 |
内科学 | 1951篇 |
皮肤病学 | 132篇 |
神经病学 | 1300篇 |
特种医学 | 321篇 |
外科学 | 1686篇 |
综合类 | 343篇 |
一般理论 | 9篇 |
预防医学 | 1541篇 |
眼科学 | 296篇 |
药学 | 813篇 |
中国医学 | 39篇 |
肿瘤学 | 820篇 |
出版年
2022年 | 111篇 |
2021年 | 206篇 |
2020年 | 136篇 |
2019年 | 202篇 |
2018年 | 267篇 |
2017年 | 179篇 |
2016年 | 174篇 |
2015年 | 195篇 |
2014年 | 279篇 |
2013年 | 454篇 |
2012年 | 625篇 |
2011年 | 674篇 |
2010年 | 364篇 |
2009年 | 303篇 |
2008年 | 565篇 |
2007年 | 671篇 |
2006年 | 637篇 |
2005年 | 652篇 |
2004年 | 571篇 |
2003年 | 567篇 |
2002年 | 554篇 |
2001年 | 298篇 |
2000年 | 332篇 |
1999年 | 290篇 |
1998年 | 150篇 |
1997年 | 151篇 |
1996年 | 130篇 |
1995年 | 142篇 |
1994年 | 132篇 |
1992年 | 241篇 |
1991年 | 223篇 |
1990年 | 226篇 |
1989年 | 214篇 |
1988年 | 196篇 |
1987年 | 189篇 |
1986年 | 172篇 |
1985年 | 185篇 |
1984年 | 141篇 |
1983年 | 127篇 |
1982年 | 117篇 |
1981年 | 127篇 |
1980年 | 123篇 |
1979年 | 149篇 |
1978年 | 102篇 |
1976年 | 102篇 |
1975年 | 103篇 |
1974年 | 107篇 |
1973年 | 122篇 |
1972年 | 101篇 |
1971年 | 104篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
82.
83.
84.
C. William Cole 《Annals of surgery》1993,218(1):105-106
85.
The authors completed a retrospective chart review of the records of all patients identified with diagnoses of mania and schizoaffective disorder, manic type, who underwent electroconvulsive therapy between the years 1973 and 1986 at McLean Hospital. Ten of 18 manic patients (56%) and 3 of 9 schizoaffective patients (33%) experienced meaningful clinical benefit. The authors report the correlation of treatment and patient factors with outcome and review the literature on the convulsive therapy of mania. 相似文献
86.
Thomas R. Zastowny Ph.D. Anthony F. Lehman M.D. M.S.P.H. Robert E. Cole Ph.D. Catherine Kane Ph.D. 《The Psychiatric quarterly》1992,63(2):159-186
This paper reports a comparison of behavioral and supportive family treatment for family management of schizophrenia. The family project applied two psychoeducational approaches to a highly treatment resistant population of young adults afflicted with chronic mental illness. The study compares and contrasts the effects of behavioral and supportive family management programs on clinical outcomes. Clinical improvements were associated with both family interventions. Discussion is provided on the relevance of this work to the growing body of evidence concerning the efficacy of psychoeducational family intervention for the management of schizophrenia. 相似文献
87.
T J Borody P Cole S Noonan A Morgan J Lenne L Hyland S Brandl E G Borody L L George 《The Medical journal of Australia》1989,151(8):431-435
The role of Campylobacter pylori gastritis in dyspepsia could be clarified more readily if reliable eradication therapy were available. Antibiotic monotherapy and combined therapy with an antibiotic agent plus a bismuth compound have yielded poor long-term results. In this study, bismuth-tetracycline-metronidazole triple therapy has been used to eradicate C. pylori infection in 100 consecutive patients who were suffering from either a duodenal ulcer or non-ulcer dyspepsia. Examination of a follow-up endoscopic biopsy at eight weeks after treatment showed an eradication rate of C. pylori of 94%. Of 64 patients whose biopsy samples were free of C. pylori infection at eight weeks and who were available for reassessment, 60 (94%) patients had samples that remained free of C. pylori infection on examination of a repeat endoscopic biopsy at 12-37 months (mean, 19.3 months). It is concluded that "triple chemotherapy" can achieve long-term eradication of C. pylori infection effectively in the majority of treated patients and that the recurrence of duodenal ulcers thus may be diminished. 相似文献
88.
CD8: Adhesion Molecule, Co-Receptor and Immuno-Modulator 总被引:2,自引:0,他引:2
CD8 is a cell surface glycoprotein found in cytotoxic T lymphocytes, which are important components in cellular immunity, esp. in the immune response to cancer and chronic infections. There are two forms of CD8, either as an alphaalpha homodimer or alphabeta heterodimer. It acts as an "assistant" or co-receptor in the function of cytotoxic T cells where specific immunity is mediated by interaction of specific T cell receptor (alphabeta TCR) and its ligand peptide major histocompatibility complex (pMHC). CD8 also binds to pMHC but away from the interface of pMHC and TCR contact, thereof no influence on the specificity of this interaction. If the TCR and CD8 bind to the same pMHC at the same time, CD8 is defined as a co-receptor, functioning through its signalling via its cytoplasmic tyrosine phosphorylation pathway; if CD8 binds to pMHC independently of the TCR, it is defined as an adhesion molecule. At present, the co-receptor function theory is dominated in the field. Recent study has also shown that murine CD8 alphaalpha binds to TL antigen, an MHC homologue, therefore acts as an immuno-modulator. In this review, we discuss these current understandings of the three aspects of the CD8 functions and their structural basis. 相似文献
89.
Immunosuppressive properties of the Mycoplasma arthritidis T-cell mitogen in vivo: inhibition of proliferative responses to T-cell mitogens. 总被引:1,自引:2,他引:1
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We have previously shown that Mycoplasma arthritidis produces a soluble T-cell mitogen (MAM) which is active for most mouse strains that express the alpha chain of the I-E molecule (E alpha) encoded within the murine major histocompatibility complex. The lymphocytes from mice injected intravenously with the MAM exhibited a marked decrease in their ability to respond in vitro to MAM, to phytohemagglutinin, or to concanavalin A T-cell mitogens. Suppression could only be induced in MAM-responsive mouse strains and was most marked 1 to 4 days postinjection. Splenic and node cells and, to a lesser extent, thymic cells from MAM-injected mice could inhibit the ability of lymphocytes from normal mice to respond to MAM and lectin mitogens. A minimum of 2.5 x 10(4) viable cells was required for significant transfer of suppression, and no major histocompatibility complex restrictions were seen. Unlike concanavalin A-induced suppressor cells, which consist of a CD4-, CD8+ T-cell subset, suppressor cells induced by MAM were due to a CD4+ CD8- subset. We hypothesize that MAM may play a role in M. arthritidis-mediated disease by both its inflammatory and immunosuppressive properties. 相似文献
90.
Toxicity but not arthritogenicity of Mycoplasma arthritidis for mice associates with the haplotype expressed at the major histocompatibility complex. 总被引:3,自引:4,他引:3
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The use of inbred and congenic mouse strains established that toxicity and death induced by Mycoplasma arthritidis associates with the haplotype expressed at the murine major histocompatibility complex. Mice bearing H-2k and H-2d are susceptible, whereas those bearing H-2b are much more resistant. Mice susceptible to toxicity exhibited massive peritoneal adhesions and a decreased ability to clear organisms from the peripheral circulation. However, the severity of acute arthritis developing over a 3-month period was not statistically related to the haplotype expressed at the major histocompatibility complex. Lymphocyte activation in vitro by a soluble T-cell mitogen is also dependent on a similar haplotype expression. 相似文献