全文获取类型
收费全文 | 420篇 |
免费 | 34篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 31篇 |
妇产科学 | 9篇 |
基础医学 | 43篇 |
口腔科学 | 1篇 |
临床医学 | 64篇 |
内科学 | 81篇 |
皮肤病学 | 3篇 |
神经病学 | 38篇 |
特种医学 | 26篇 |
外科学 | 43篇 |
综合类 | 13篇 |
预防医学 | 42篇 |
眼科学 | 2篇 |
药学 | 50篇 |
肿瘤学 | 21篇 |
出版年
2024年 | 2篇 |
2022年 | 6篇 |
2021年 | 12篇 |
2020年 | 2篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 10篇 |
2015年 | 5篇 |
2014年 | 16篇 |
2013年 | 13篇 |
2012年 | 15篇 |
2011年 | 22篇 |
2010年 | 11篇 |
2009年 | 8篇 |
2008年 | 16篇 |
2007年 | 37篇 |
2006年 | 18篇 |
2005年 | 20篇 |
2004年 | 17篇 |
2003年 | 12篇 |
2002年 | 11篇 |
2001年 | 12篇 |
2000年 | 13篇 |
1999年 | 6篇 |
1998年 | 11篇 |
1997年 | 10篇 |
1996年 | 9篇 |
1995年 | 8篇 |
1994年 | 9篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1990年 | 11篇 |
1989年 | 9篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 9篇 |
1985年 | 10篇 |
1984年 | 8篇 |
1983年 | 3篇 |
1982年 | 9篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1977年 | 2篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1969年 | 3篇 |
1967年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有470条查询结果,搜索用时 31 毫秒
51.
52.
Golledge Jonathan; Karan Mirko; Moran Corey S.; Muller Juanita; Clancy Paula; Dear Anthony E.; Norman Paul E. 《European heart journal》2008,29(5):665-672
Aims: Diabetes increases the risk of atherothrombosis, but reducesthe risk of abdominal aortic aneurysm (AAA). The reason forthis difference is unknown. We examined the role of diabetesand glycation on AAA expansion and extracellular matrix–monocyteinteractions. Methods and results: We followed 198 patients (20 with diabetes) who had 30–45mm AAAs with yearly aortic ultrasound for 3 years. Diabeteswas independently associated with reduced AAA growth (β= –0.17, P = 0.01; OR for expansion above median 0.18,95% confidence interval 0.06–0.57). In vitro incubationof resting human monocytes with glycated bovine serum albuminor monomeric type I collagen increased matrix metalloproteinase(MMP) secretion. In contrast, exposure of activated monocytesto glycated type I collagen lattices induced a marked reductionin MMP and interleukin-6 secretion. This de-activating effectwas also demonstrated in cross-linked non-glycated collagenlattices, healthy decellularized aortic media, and decellularizedaortic media from diabetes patients with atherosclerosis. Incontrast, decellularized aortic media from patients with atherosclerosis,but no diabetes, induced increased MMP secretion. Conclusion: These findings confirm that the progression of AAA is slowerin patients with diabetes and suggest a mechanism by which theaortic media may be protected from degradation in these individuals. 相似文献
53.
Acute-on-chronic kidney disease will be familiar to many nephrologists. Hsu et al. quantify the risk of acute-on-chronic disease across the stages of preexisting chronic kidney disease. Their study demonstrates the valuable insights that large epidemiological studies can bring to the field of acute kidney injury. 相似文献
54.
55.
N-ethyl-N-nitrosourea (ENU) mutagenesis in mice has become a standard tool for (i) increasing the pool of mutants in many areas of biology, (ii) identifying novel genes involved in physiological processes and disease, and (iii) in assisting in assigning functions to genes. ENU is assumed to cause random mutations throughout the mouse genome, but this presumption has never been analyzed. This is a crucial point, especially for large-scale mutagenesis, as a bias would reflect a constraint on identifying possible genetic targets. There is a significant body of published data now available from both phenotype-driven and gene-driven ENU mutagenesis screens in the mouse that can be used to reveal the effectiveness and limitations of an ENU mutagenesis approach. Analysis of the published data is presented in this paper. As expected for a randomly acting mutagen, ENU-induced mutations identified in phenotype-driven screens were in genes that had higher coding sequence length and higher exon number than the average for the mouse genome. Unexpectedly, the data showed that ENU-induced mutations were more likely to be found in genes that had a higher G + C content and neighboring base analysis revealed that the identified ENU mutations were more often directly flanked by G or C nucleotides. ENU mutations from phenotype-driven and gene-driven screens were dominantly A:T to T:A transversions or A:T to G:C transitions. Knowledge of the spectrum of mutations that ENU elicits will assist in positional cloning of ENU-induced mutations by allowing prioritization of candidate genes based on some of their inherent features. 相似文献
56.
57.
D. N. Bateman J. W. Dear R. Carroll J. Pettie T. Yamamoto M. E. M. O. Elamin 《Clinical toxicology (Philadelphia, Pa.)》2014,52(8):868-872
Background. On 3 September 2012, the licensed indication for acetylcysteine was changed in the United Kingdom (UK) so that all patients with a plasma paracetamol concentration above a “100 mg/L” (4 h post ingestion) nomogram treatment line after an acute paracetamol (acetaminophen) overdose should be treated. This is a lower threshold than that used in the United States, Canada, Australia, and New Zealand. Here we report the impact of this change in the UK on the management of patients with acute overdose in different paracetamol concentration ranges. Methods. This is a cohort study, consisting of a retrospective analysis conducted on prospectively collected audit data in three UK hospitals. Following appropriate ethical and data protection authority approval, data for patients presenting within 24 h of an acute timed single paracetamol overdose were extracted. Numbers of admissions and use of antidote in relation to different paracetamol concentration bands (< 100 mg/L; 100–149 mg/L; 150–199 mg/L; and ≥ 200 mg/L at 4 h) were analyzed for one-year periods before and after the change. Results. Comparing the year before with the year after the change, there was no change in the numbers of patients presenting to hospital within 24 h of acute timed paracetamol overdose (1246 before and 1251 after), but more patients were admitted (759 before and 849 after) and treated with acetylcysteine (389 before and 539 after). Of the 150 additional patients treated with acetylcysteine in the year following the change, 114 (76%, 95% CI: 68.4–82.6) were in the 100–149 group and 9 (6.0%, 95% CI: 2.8–11.1) in the 150–199 group. Conclusions. Changes to national guidelines for managing paracetamol poisoning in the UK have increased the numbers of patients with acute overdose treated with acetylcysteine, with most additional treatments occurring in patients in the 100–149 mg/L dose range, a group at low risk of hepatotoxicity and higher risk of adverse reactions. 相似文献
58.
Gamma (immune) interferon production by leukocytes from a patient with a TG cell proliferative disease 总被引:7,自引:0,他引:7
We report a patient with a disease characterized by proliferation of T cells with Fc receptors for IgG (TG). However, unlike lymphoid cells from normal individuals or from patients with other lymphoid malignancies, the patient's lymphocytes spontaneously produced gamma interferon (IFN-gamma) in vitro. The peripheral lymphocytes consisted of 95% TG cells, which exhibited the morphological characteristics of T- cell chronic lymphocytic leukemia (CLL) and were normal on cytochemical and chromosome analysis. The majority of TG cells were OKT3+, OKT8+, and OKT4-, 3A1-. These cells failed to express suppressor cell activity and displayed depressed levels of natural killer activity, but mediated antibody-dependent cell-mediated cytotoxicity. The spontaneous production of IFN-gamma by human peripheral lymphoid cells as demonstrated in this study may serve as a probe for studying the relationship between IFN-gamma and the proliferation of human T-cell subsets. 相似文献
59.
Human erythrocyte antigens: II. The In(Lu) gene regulates expression of an antigen on an 80-kilodalton protein of human erythrocytes 总被引:3,自引:0,他引:3
We have previously shown that a murine monoclonal antibody (A3D8) identifies a human erythrocyte protein antigen whose expression is regulated by the Lutheran inhibitor [In(Lu)] gene. In the present study, we demonstrated by immunoprecipitation and Western blot techniques that the antigen defined by A3D8 was on an 80-kD erythrocyte membrane protein. A second 170-kD protein was coprecipitated with the 80-kD protein but failed to show antigen activity by Western blot analysis. The 170-kD protein, when analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis in two dimensions, was composed of 50- and 30-kD disulfide-linked subunits. In(Lu) Lu[a-b-) erythrocytes differed from Lu(a+b+) or Lu(a-b+) erythrocytes in that In(Lu) deoxycholate erythrocyte membrane extracts contained trace amounts of immunoprecipitable 80-kD protein compared with detergent-solubilized erythrocyte membrane extracts prepared from Lu(a+b+) or Lu(a-b+) subjects. 相似文献
60.
GG Alvarez BF Burns M Desjardins SR Salahudeen F AlRashidi DW Cameron 《Canadian respiratory journal》2006,13(8):441-444
Blastomyces dermatitidis is a dimorphic fungus endemic to northwestern Ontario, Manitoba and some parts of the United States. The fungus is also endemic to parts of Africa. Pulmonary and extrapulmonary findings of a 24-year-old African man who presented with weight loss, dry cough and chronic pneumonia not resolving with antibiotic treatment are presented. The unusual occurrence of pulmonary blastomycosis associated with skin lesions and a moderate pleural effusion is reported. 相似文献