全文获取类型
收费全文 | 19946篇 |
免费 | 1875篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 260篇 |
儿科学 | 711篇 |
妇产科学 | 526篇 |
基础医学 | 2959篇 |
口腔科学 | 376篇 |
临床医学 | 2293篇 |
内科学 | 3902篇 |
皮肤病学 | 216篇 |
神经病学 | 1509篇 |
特种医学 | 978篇 |
外国民族医学 | 3篇 |
外科学 | 2467篇 |
综合类 | 516篇 |
一般理论 | 25篇 |
预防医学 | 2078篇 |
眼科学 | 265篇 |
药学 | 1583篇 |
2篇 | |
中国医学 | 13篇 |
肿瘤学 | 1160篇 |
出版年
2021年 | 277篇 |
2019年 | 273篇 |
2018年 | 289篇 |
2017年 | 208篇 |
2016年 | 241篇 |
2015年 | 297篇 |
2014年 | 423篇 |
2013年 | 615篇 |
2012年 | 839篇 |
2011年 | 932篇 |
2010年 | 503篇 |
2009年 | 429篇 |
2008年 | 765篇 |
2007年 | 795篇 |
2006年 | 803篇 |
2005年 | 806篇 |
2004年 | 727篇 |
2003年 | 672篇 |
2002年 | 678篇 |
2001年 | 602篇 |
2000年 | 645篇 |
1999年 | 533篇 |
1998年 | 277篇 |
1997年 | 223篇 |
1996年 | 252篇 |
1995年 | 254篇 |
1994年 | 220篇 |
1993年 | 211篇 |
1992年 | 497篇 |
1991年 | 488篇 |
1990年 | 465篇 |
1989年 | 445篇 |
1988年 | 415篇 |
1987年 | 436篇 |
1986年 | 446篇 |
1985年 | 432篇 |
1984年 | 326篇 |
1983年 | 278篇 |
1982年 | 216篇 |
1981年 | 182篇 |
1980年 | 170篇 |
1979年 | 313篇 |
1978年 | 238篇 |
1977年 | 214篇 |
1976年 | 176篇 |
1975年 | 186篇 |
1974年 | 180篇 |
1973年 | 189篇 |
1972年 | 167篇 |
1971年 | 163篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
Claire-Jehanne Dubouloz Diane Laporte Martha Hall Brenda Ashe C Douglas Smith 《The American journal of occupational therapy》2004,58(4):398-407
The purpose of this qualitative study was to examine the process of transformation of personal beliefs, values, feelings, and knowledge (meaning perspectives) underlying occupational change in a small group of clients with rheumatoid arthritis during home-based rehabilitation. A grounded theory approach used to collect and analyze data concurrently included: (1) a sample of five adult clients diagnosed with rheumatoid arthritis in occupational therapy, (2) data collection through 28 semi-directed interviews, and (3) data analysis using the constant comparison method. The study identified meaning perspectives of these clients with rheumatoid arthritis and explored the transformation of perspectives related to the modification of occupational performance. The study suggests that the exploration of meaning perspective transformation by clients and therapists could be a potential part of rehabilitation intervention. 相似文献
23.
A series of 5-alkyl-5-phenylbarbituric acid analogues were shown to be potent hypolipidemic agents in rats and mice at 20 mg/kg/day. This dose is lower than that required for hypolipidemic activity for clofibrate and nicotinic acid derivatives in rodents and man. These new derivatives reduced both serum cholesterol and triglyceride levels in rodents by either the oral or intraperitoneal route of administration. Previous studies have demonstrated that similar heterocyclic compounds, i.e. cyclic imides, glutarimides and hydantoins are potent hypolipidemic agents in rodents. The barbituric acid derivatives probably interfered with de novo synthesis of cholesterol and fatty acids in the early steps since the agents inhibit the activities of ATP-dependent citrate lyase and acetyl-CoA synthetase. Triglyceride synthesis may be blocked since the agents inhibited the rate limiting enzyme, sn-glycerol-3-phosphate-acyl-transferase. Rat tissue lipids especially cholesterol and triglycerides were reduced after 14 days treatment. Fecal lipids were increased in cholesterol and phospholipid content by selected compounds. The rat serum lipoprotein after 14 days drug administration showed reduced VLDL-cholesterol and HDL-triglyceride contents. The modulation of the lipid content of the serum lipoproteins by the barbituric acids suggest that these agents may be helpful in treating clinical hyperlipidemic disease states. 相似文献
24.
James K. Hartsfield Bryan D. Hall Arthur W. Grix Boris G. Kousseff Jose F. Salazar Scott M. W. Haufe 《American journal of medical genetics. Part A》1993,45(5):552-557
We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc. 相似文献
25.
26.
Amrik Sahota Min Yang Sujuan Gao Siu L. Hui Olusegun Baiyewu Oyewusi Gureje Steven Oluwole Adesola Ogunniyi Kathleen S. Hall Hugh C. Hendrie 《Annals of neurology》1997,42(4):659-661
As a part of our ongoing study on Alzheimer's disease (AD) in elderly African Americans, we obtained clinical assessment and apolipoprotein E (ApoE) genotype data on 288 individuals (including 60 with AD). The ApoE σ4 allele frequency was significantly increased in AD patients compared with controls. The age-adjusted odds ratio (OR) for AD in σ4 homozygotes was 4.83 (95% confidence interval [CI], 1.71–13.64) compared with the σ3/σ3 genotype, but the OR for AD with the σ3/σ4 genotype did not reach significance (1.20; 95% CI, 0.58–2.45). These findings suggest that the association between ApoE σ4 and AD is weaker in African Americans than in whites. 相似文献
27.
Treatment of dyskeratosis congenita with Granulocyte Colony-Stimulating Factor and Erythropoietin 总被引:1,自引:0,他引:1
Blanche P. Alter Frank H. Gardner & Robert E. Hall 《British journal of haematology》1997,97(2):309-311
Aplastic anaemia is both frequent and difficult to manage in patients with dyskeratosis congenita (DC). We recently treated a 23-year-old male for a year with granulocyte colony-stimulating factor (G-CSF) and erythropoietin (Ep), with an excellent neutrophil response, and a transient effect on haemoglobin levels. G-CSF alone or combined with other cytokines may provide at least a partial effect in pancytopenic patients with DC. 相似文献
28.
Urinary tract injuries during obstetric intervention 总被引:11,自引:0,他引:11
Dhanasekaran Rajasekar Supervisory Senior House Officer Marion Hall Consultant 《BJOG : an international journal of obstetrics and gynaecology》1997,104(6):731-734
A retrospective case record review of obstetric urinary tract injury in the Grampian region from 1976 to 1993 identified 16 cases of bladder injury (0.1 per 1000 deliveries, 1.4 per 1000 caesarean sections and four cases of ureteric injury (0.03 per 1000 deliveries, 0.27 per 1000 caesarean sections). Diagnosis of bladder injury was immediate, but of ureteric injury often delayed. Although the injury rates are lower than previously reported and previously reported risk factors not confirmed, this audit has resulted in guidelines for junior staff, compliance with which will be monitored, and every case of urinary tract injury will be reviewed. 相似文献
29.
OXA-14, another extended-spectrum variant of OXA-10 (PSE-2) beta-lactamase from Pseudomonas aeruginosa. 下载免费PDF全文
Pseudomonas aeruginosa 455, isolated in Ankara, Turkey, produced a pI 6.2 beta-lactamase determined by plasmid pMLH53 and resisted all beta-lactams except carbapenems. This beta-lactamase, named OXA-14, corresponded to OXA-10 (PSE-2) except that aspartate replaced glycine at position 157 and thus is intermediate between OXA-10 and OXA-11, which has aspartate at position 157 and a further substitution at position 143. 相似文献
30.
Bo-Lennart Johansson Ulla Berg Ulla Freyschuss Kerstin Hall Staffan Troell 《Pediatric nephrology (Berlin, Germany)》1990,4(6):589-592
The influence of metabolic control (HbA1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients. 相似文献