全文获取类型
收费全文 | 17828篇 |
免费 | 1285篇 |
国内免费 | 67篇 |
专业分类
耳鼻咽喉 | 127篇 |
儿科学 | 547篇 |
妇产科学 | 537篇 |
基础医学 | 2475篇 |
口腔科学 | 291篇 |
临床医学 | 2033篇 |
内科学 | 3368篇 |
皮肤病学 | 478篇 |
神经病学 | 1798篇 |
特种医学 | 492篇 |
外科学 | 1875篇 |
综合类 | 113篇 |
一般理论 | 7篇 |
预防医学 | 1951篇 |
眼科学 | 423篇 |
药学 | 1054篇 |
1篇 | |
中国医学 | 19篇 |
肿瘤学 | 1591篇 |
出版年
2024年 | 25篇 |
2023年 | 234篇 |
2022年 | 355篇 |
2021年 | 686篇 |
2020年 | 465篇 |
2019年 | 582篇 |
2018年 | 757篇 |
2017年 | 509篇 |
2016年 | 604篇 |
2015年 | 669篇 |
2014年 | 824篇 |
2013年 | 1109篇 |
2012年 | 1630篇 |
2011年 | 1600篇 |
2010年 | 811篇 |
2009年 | 759篇 |
2008年 | 1162篇 |
2007年 | 1175篇 |
2006年 | 1025篇 |
2005年 | 947篇 |
2004年 | 825篇 |
2003年 | 752篇 |
2002年 | 713篇 |
2001年 | 86篇 |
2000年 | 50篇 |
1999年 | 76篇 |
1998年 | 106篇 |
1997年 | 101篇 |
1996年 | 62篇 |
1995年 | 52篇 |
1994年 | 49篇 |
1993年 | 56篇 |
1992年 | 39篇 |
1991年 | 24篇 |
1990年 | 21篇 |
1989年 | 19篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 18篇 |
1985年 | 16篇 |
1984年 | 18篇 |
1983年 | 16篇 |
1982年 | 23篇 |
1981年 | 12篇 |
1980年 | 10篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1977年 | 9篇 |
1971年 | 8篇 |
1967年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
Marc L. Copersino Christina S. Meade George E. Bigelow Robert K. Brooner 《Journal of substance abuse treatment》2010
This study compares the frequencies of retrospective self-reported HIV high-risk drug use and sexual behaviors in 127 out-of-treatment injection drug users using the HIV Risk Questionnaire (HRQ) across two administration methods: (a) a brief standard quantity–frequency approach covering the past 30 days and (b) a lengthier timeline follow-back (TLFB) procedure for improving recall. The two procedures produced similar frequencies of risk behavior across most items (80%) and good intra- and interclass correlation coefficients. The TLFB, however, resulted in higher frequencies for two risk behavior questions—sharing of any drug injection equipment and having any type of unprotected sex. The TLFB is a well-established procedure for retrospective assessment of HIV risk behavior and a good choice when precision in measuring these behaviors is a primary focus of the work. In contrast, the brief HRQ-Standard interview procedure appears to be a reasonable choice for clinical, research, and health-related surveys where the primary focus is broader than HIV risk behavior. 相似文献
102.
Cvirn G Cimenti C Kutschera J Ferstl U Wagner T Muntean W Jurgens G Gallistl S Koestenberger M 《European journal of pediatrics》2007,166(5):427-431
In the present study, we comparatively evaluated the anticoagulant efficacy of the new direct thrombin inhibitor melagatran
in cord vs. adult plasma. In contrast to heparin, melagatran does not require antithrombin as a cofactor. Thus, anticoagulant
treatment with melagatran is of special interest in neonatal patients, whose plasma is relatively deficient in antithrombin.
We evaluated the anticoagulant action of increasing amounts of melagatran (0.1–2.0 μmol/l) in both cord and adult plasma by
means of calibrated automated thrombography (CAT) with respect to the lag time until the onset of thrombin formation, time
to thrombin peak maximum (TTP), endogenous thrombin potential (ETP), and thrombin peak height. Melagatran exhibited approximately
the same ability to prolong lag times or TTPs in both cord and adult plasma. Similar concentrations (IC50) of melagatran were required to double the lag times (0.44±0.04 μmol/l vs. 0.52±0.05 μmol/l) or to double the TTPs (0.91±0.08 μmol/l
vs. 1.06±0.09 μmol/l) in cord vs. adult plasma. Melagatran exhibited a higher ability to suppress ETPs or thrombin peak heights
in cord vs. adult plasma. Markedly lower concentrations (IC50) of melagatran were required to suppress ETPs (0.27±0.03 μmol/l vs. 0.70±0.06 μmol/l) or thrombin peak heights by 50% (0.29±0.03 μmol/l
vs. 0.53±0.04 μmol/l) in cord vs. adult plasma. We conclude that our results suggest a higher ability of melagatran to suppress
thrombin formation in cord vs. adult plasma. Thus, lower amounts of melagatran might be required in neonates undergoing antithrombotic
therapy. 相似文献
103.
Tyl RW Myers CB Marr MC Fail PA Seely JC Brine DR Barter RA Butala JH 《Reproductive toxicology (Elmsford, N.Y.)》2004,18(2):241-264
Butyl benzyl phthalate (BBP) was administered in the diet at 0, 750, 3750, and 11,250 ppm ad libitum to 30 rats per sex per dose for two offspring generations, one litter/breeding pair/generation, through weaning of F2 litters. Adult F0 systemic toxicity and adult F1 systemic and reproductive toxicity were present at 11,250 ppm (750 mg/kg per day). At 11,250 ppm, there were reduced F1 and F2 male anogenital distance (AGD) and body weights/litter during lactation, delayed acquisition of puberty in F1 males and females, retention of nipples and areolae in F1 and F2 males, and male reproductive system malformations. At 3750 ppm (250 mg/kg per day), only reduced F1 and F2 offspring male AGD was present. There were no effects on parents or offspring at 750 ppm (50 mg/kg per day). The F1 parental systemic and reproductive toxicity no observable adverse effect level (NOAEL) was 3750 ppm. The offspring toxicity NOAEL was 3750 ppm. The offspring toxicity no observable effect level (NOEL) was 750 ppm, based on the presence of reduced AGD in F1 and F2 males at birth at 3750 ppm, but no effects on reproductive development, structures, or functions. 相似文献
104.
105.
David J Browning Christina M Fraser Michelle E Powers 《Ophthalmic surgery, lasers & imaging》2006,37(5):399-405
BACKGROUND AND OBJECTIVE: To provide a tool for analyzing optical coherence tomography data in patients with diabetic macular edema. PATIENTS AND METHODS: Retrospective series of 206 patients with diabetic macular edema involving at least one eye and receiving focal laser photocoagulation, intravitreal triamcinolone acetonide injection, or vitrectomy, membrane peeling, and intravitreal triamcinolone acetonide injection, and of untreated fellow eyes without diabetic macular edema. Main outcome measures included foveal subfield mean thickness and thickening relative to normal (microns), total macular volume and its increase relative to normal (mm3), visual acuity (Snellen decimal), and intraocular pressure (mm Hg). RESULTS: The authors demonstrate a graphical display of data based on a spreadsheet template for the longitudinal management of diabetic macular edema. Complex relationships of ocular response and interventions are concisely displayed. CONCLUSION: A graphical display of optical coherence tomography, visual acuity, and intraocular pressure data is a practical aid in the management of diabetic macular edema. 相似文献
106.
Diagnostic and management challenges from childhood,puberty through to transition in severe insulin resistance due to insulin receptor mutations 下载免费PDF全文
Two Caucasian girls, both of normal weight and body mass indices, were diagnosed with type A insulin resistance (IR) in childhood. Case 1 presented with premature adrenarche aged 7 years, then by age 12 years had hirsutism, acne, acanthosis nigricans, and asymptomatic diabetes. Subsequent investigation revealed raised adiponectin (15.3 mg/L) and heterozygous p.Pro1205Leu mutation in the INSR gene encoding the insulin receptor. She experienced postprandial hypoglycaemia on metformin; acarbose was trialled and discontinued aged 16 years, as she became normoglycaemic. Hirsutism was treated with topical eflornithine, oral spironolactone and flutamide, and laser therapy. Unfortunately, diabetes reemerged in young adulthood with obesity. Case 2: during an emergency admission for acute abdominal pain aged 11 years, hyperglycaemia was noted which led to further investigation. An oral glucose tolerance test showed diabetes and ultrasound showed polycystic ovaries. Further investigations revealed raised adiponectin (18 mg/L) and compound heterozygous mutations in the INSR gene: p.Pro1263Ala and p.Ser748Leu (latter probable normal variant). She was treated with metformin and experienced postprandial hypoglycaemia. Symptoms of hyperandrogenism were controlled by flutamide. She maintained a healthy weight and reassessment at young adulthood showed resolution of diabetes. Type A IR may present in childhood with overlapping features of common endocrine entities such as premature adrenarche and polycystic ovarian syndrome. Patients with abnormal glucose tolerance yet normal weight merit screening with adiponectin; raised adiponectin levels prompt insulin receptor mutational analysis. Postprandial hypoglycaemia is characteristic. Management includes optimization of glycaemic control with oral hypoglycaemic agents and maintenance of healthy weight, and controlling the effects of hyperandrogenism. 相似文献
107.
108.
109.
110.
A 51-year-old woman presented with a large abdominopelvic mass suspicious on preoperative imaging for ovarian malignancy. At laparotomy, a large cystic mass was found originating from the uterus and adherent to the proximal ileum. Pathologic evaluation confirmed the diagnosis of cystic leiomyoma. 相似文献