全文获取类型
收费全文 | 1781篇 |
免费 | 114篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 43篇 |
妇产科学 | 40篇 |
基础医学 | 240篇 |
口腔科学 | 32篇 |
临床医学 | 320篇 |
内科学 | 351篇 |
皮肤病学 | 17篇 |
神经病学 | 148篇 |
特种医学 | 28篇 |
外科学 | 184篇 |
综合类 | 19篇 |
一般理论 | 7篇 |
预防医学 | 217篇 |
眼科学 | 27篇 |
药学 | 122篇 |
中国医学 | 1篇 |
肿瘤学 | 76篇 |
出版年
2023年 | 17篇 |
2022年 | 12篇 |
2021年 | 37篇 |
2020年 | 25篇 |
2019年 | 51篇 |
2018年 | 46篇 |
2017年 | 31篇 |
2016年 | 33篇 |
2015年 | 36篇 |
2014年 | 61篇 |
2013年 | 97篇 |
2012年 | 141篇 |
2011年 | 156篇 |
2010年 | 85篇 |
2009年 | 73篇 |
2008年 | 112篇 |
2007年 | 136篇 |
2006年 | 97篇 |
2005年 | 107篇 |
2004年 | 111篇 |
2003年 | 101篇 |
2002年 | 111篇 |
2001年 | 18篇 |
2000年 | 19篇 |
1999年 | 17篇 |
1998年 | 16篇 |
1997年 | 13篇 |
1996年 | 15篇 |
1995年 | 21篇 |
1994年 | 10篇 |
1993年 | 10篇 |
1992年 | 13篇 |
1991年 | 7篇 |
1990年 | 9篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1968年 | 1篇 |
1965年 | 1篇 |
1962年 | 1篇 |
1907年 | 1篇 |
排序方式: 共有1900条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
John Leeton Lesley Freemann Catriona King Therese Brady Lain Cameron Jayne Harman 《Journal of assisted reproduction and genetics》1988,5(1):22-24
A fertile woman suffering from mild dystrophia myotonica had undergone sterilization because of the 50% genetic risk of this disease developing in her offspring. In her second treatment cycle on the donor oocyte program, four anonymously donated oocytes were inseminated with frozen-thawed sperm of her husband. Three embryos were obtained and two surviving embryos were deep-frozen at the eight-cell stage and kept in storage for 9 months. These embryos were successfully thawed and transferred to the recipient 97 hr after the onset of her luteinizing hormone surge. A normal singleton pregnancy developed and a healthy male infant was delivered by cesarean section at 36 weeks of gestation. 相似文献
65.
The Donation of Oocytes to Known Recipients 总被引:2,自引:0,他引:2
John Leeton MGO FRACS FRACOG Jayne Harman SRN 《The Australian & New Zealand journal of obstetrics & gynaecology》1987,27(3):248-250
The supply of donated oocytes from an in vitro fertilization programme has always been inadequate, especially following the successful cryopreservation of human embryos. There have been no previous reports of women donating their oocytes to known recipients. All of 7 women who donated all their oocytes to known recipients responded to a posted questionnaire. No differences in social characteristics between this group and another group of infertile women treated on an in vitro fertilization programme, who donated some of their excess oocytes anonymously were noted, except that the known donor group had a relatively high average parity, i.e. 3. No differences in attitudes towards donating oocytes were noted between these groups except that the known donor group felt a significantly greater connection towards the potential child. 相似文献
66.
A survey of acute trusts' nurse cadet schemes in England showed a wide variety in entry requirements and qualifications offered. Most schemes offered successful students a place on a nurse training scheme. Legal issues surrounding 16-year-olds working in hospitals need to be clarified. Standardisation of entry requirements and course qualifications is required. At present, a student could complete a cadet course in one part of the country and not be eligible for nurse training elsewhere. 相似文献
67.
68.
McDonald HA Chu KL Bianchi BR McKenna DG Briggs CA Burgard EC Lynch KJ Faltynek C Cartmell J Jarvis MF 《European journal of pharmacology》2002,435(2-3):135-142
In this study, the receptor desensitizing effects of diadenosine polyphosphates at recombinant human P2X3 (hP2X3) receptors were examined. Administration of Ap3A, Ap4A, Ap5A or Ap6A inhibited the hP2X3 receptor-mediated response to a subsequent application of 3 muM alphabeta-methyleneATP (alphabeta-meATP), in a concentration-dependent manner, with IC50 values 2707, 42, 59 and 46 nM, respectively. These agonists did not desensitize alphabeta-meATP responses mediated by the slowly desensitizing heteromeric human P2X2/3 receptor. hP2X3 receptor desensitization was reversible and was not observed following the increase in intracellular Ca2+ levels produced by carbachol. A similar pattern of desensitization evoked by Ap5A was also observed using electrophysiological recordings of Xenopus oocytes expressing hP2X3 receptors. These data demonstrate that diadenosine polyphosphates, found endogenously in the central nervous system, can readily desensitize hP2X3 receptors at nanomolar concentrations that are 10-fold lower than are required to produce agonist-induced receptor activation. Thus, P2X3 receptor desensitization by diadenosine polyphosphates may provide an important modulatory mechanism of P2X3 receptor activation in vivo. 相似文献
69.
The endothelin antagonist BQ123 reduces pulmonary vascular resistance after surgical intervention for congenital heart disease 总被引:12,自引:0,他引:12
Schulze-Neick I Li J Reader JA Shekerdemian L Redington AN Penny DJ 《The Journal of thoracic and cardiovascular surgery》2002,124(3):435-441
OBJECTIVE: Postoperative pulmonary hypertension in children after surgical intervention for congenital heart disease has been attributed to failure of the pulmonary endothelium to provide adequate vasodilation. Although we have shown that the impaired vasodilatory component attributable to the l-arginine-nitric oxide pathway is almost completely reversible, a nonrestorable component persists, implying an additional vasoconstrictive mechanism in postoperative pulmonary endothelial dysfunction. In this study of children after surgical intervention for congenital heart disease, we measured endothelin-1 levels and used BQ123, a selective endothelin-A receptor antagonist, together with inhaled nitric oxide to discriminate dysfunctional pulmonary endothelial vasodilation from endothelin-mediated pulmonary vasoconstriction. METHODS: All children were examined early after surgical intervention in the intensive care unit. Pulmonary vascular resistance (with respiratory mass spectrometry), as well as arterial and venous endothelin-1 levels (measured by means of a quantitative enzyme-linked immunosorbent assay), were determined in 7 children (age range, 3.3-13.7 months; median age, 6.3 months) with intracardiac shunting defects at baseline and during ventilation with a fraction of inspired oxygen of 0.65, with additional BQ123 (0.1 mg/kg infused over 20 minutes), and with inhaled nitric oxide (20 ppm). RESULTS: Pulmonary vascular resistance decreased from 7.7 +/- 3.4 at baseline to 6.1 +/- 2.8 Woods units. m(-2) (P =.022) at a fraction of inspired oxygen of 0.65 and to 4.7 +/- 2.7 Woods units. m(-2) (P =.013) during BQ123 infusion. Inhaled nitric oxide had no further effect on pulmonary vascular resistance. Left atrial endothelin-1 levels (1.35-5.12 pg/mL; mean, 2.4 pg/mL) correlated significantly with the decrease in pulmonary vascular resistance in response to BQ123 infusion (r(2) = 0.89, P =.003). CONCLUSION: Postoperative elevation of pulmonary vascular resistance in children after surgical intervention for congenital heart disease is responsive to endothelin-A blockade with BQ123. Increased levels of endothelin-1 predict the response to this therapy, which might become an important addition to the clinical armamentarium in postoperative pulmonary hypertensive disease. 相似文献
70.
Determinants of outcome in ANCA-associated glomerulonephritis: a prospective clinico-histopathological analysis of 96 patients 总被引:8,自引:0,他引:8
Hauer HA Bajema IM Van Houwelingen HC Ferrario F Noël LH Waldherr R Jayne DR Rasmussen N Bruijn JA Hagen EC;European Vasculitis Study Group 《Kidney international》2002,62(5):1732-1742
BACKGROUND: The predictive value of clinical and renal histological features for renal outcome in patients with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis was investigated in a prospective analysis of 96 patients with ANCA-associated vasculitis, and moderate renal involvement (creatinine <500 micromol/L). METHODS: The extent of 39 histological features in 96 biopsies (performed at entry in a clinical trial) was scored by two independent observers, according to a standardized protocol. Age, gender, diagnosis, glomerular filtration rate at entry (GFR0), ANCA-specificity, proteinuria, and treatment of these 96 patients were also taken into account. Treatment was standardized and started after the biopsy was performed. End-points included renal function at 18 months (GFR18), GFR18 corrected for GFR0 (CORGFR18), and the occurrence of relapse or death. RESULTS: Parameters that most strongly correlated with GFR18 were GFR0 (r = 0.67), interstitial fibrosis (r = -0.45), glomerulosclerosis (r = -0.37), and tubular atrophy (r = -0.36). Parameters that most strongly correlated with CORGFR18 were segmental (r = 0.45) and cellular (r = 0.30) crescents, and fibrinoid necrosis (r = 0.46). None of the clinical and histological features predicted the occurrence of relapse or death. By applying a stepwise linear multiple regression analysis, we designed a formula for the estimation of renal function at 18 months: GFR18 (mL/min) = 17 + 0.71 x GFR0 (mL/min) + 0.34 x fibrinoid necrosis (%) + 0.33 x segmental crescents (%), (r2 = 0.60; standard deviation = 19 mL/min). Our results were independent of diagnosis, ANCA-specificity, and treatment limb. CONCLUSIONS: These data suggest that in ANCA-associated glomerulonephritis, GFR0 and predominantly chronic renal lesions are potent predictors of GFR18. Active lesions are associated with renal function recovery and may be reversible. The formula for the estimation of GFR18 shows that a combination of GFR0 and renal histology is a better predictor for GFR18 than GFR0 only. 相似文献