全文获取类型
收费全文 | 1307篇 |
免费 | 88篇 |
国内免费 | 81篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 47篇 |
妇产科学 | 19篇 |
基础医学 | 160篇 |
口腔科学 | 20篇 |
临床医学 | 195篇 |
内科学 | 245篇 |
皮肤病学 | 23篇 |
神经病学 | 23篇 |
特种医学 | 329篇 |
外科学 | 117篇 |
综合类 | 27篇 |
预防医学 | 64篇 |
眼科学 | 45篇 |
药学 | 106篇 |
肿瘤学 | 48篇 |
出版年
2023年 | 7篇 |
2021年 | 10篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 16篇 |
2017年 | 9篇 |
2016年 | 13篇 |
2015年 | 16篇 |
2014年 | 18篇 |
2013年 | 29篇 |
2012年 | 29篇 |
2011年 | 29篇 |
2010年 | 29篇 |
2009年 | 40篇 |
2008年 | 30篇 |
2007年 | 76篇 |
2006年 | 17篇 |
2005年 | 34篇 |
2004年 | 26篇 |
2003年 | 32篇 |
2002年 | 24篇 |
2001年 | 25篇 |
2000年 | 27篇 |
1999年 | 30篇 |
1998年 | 73篇 |
1997年 | 76篇 |
1996年 | 56篇 |
1995年 | 63篇 |
1994年 | 40篇 |
1993年 | 41篇 |
1992年 | 36篇 |
1991年 | 39篇 |
1990年 | 45篇 |
1989年 | 55篇 |
1988年 | 46篇 |
1987年 | 37篇 |
1986年 | 40篇 |
1985年 | 61篇 |
1984年 | 28篇 |
1983年 | 20篇 |
1982年 | 28篇 |
1981年 | 15篇 |
1980年 | 28篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1977年 | 23篇 |
1976年 | 17篇 |
1975年 | 11篇 |
1966年 | 2篇 |
1944年 | 1篇 |
排序方式: 共有1476条查询结果,搜索用时 15 毫秒
51.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
52.
The magnetic resonance (MR) relaxation rates of protons were compared in the myelinated and nonmyelinated nerves of the garfish. The long, large olfactory nerve of the garfish, as an easily accessible source of nonmyelinated axons, is uniquely suited for such a comparison. The T1 and T2 measurements revealed distinct and consistent differences between nonmyelinated olfactory nerves and myelinated optic and oculomotor nerves. Comparisons between water content, lipid content, and relaxation rates indicated that the differences in MR properties represent complex differences in the distribution and physical environment of the constituent lipid and water protons. 相似文献
53.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献
54.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
55.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population. 相似文献
56.
Surface shield: device to reduce personnel radiation exposure 总被引:2,自引:0,他引:2
Young AT; Morin RL; Hunter DW; Nelson KL; Cardella JF; Castaneda-Zuniga WR; Amplatz K 《Radiology》1986,159(3):801-803
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed. 相似文献
57.
Urine-compatible polymer for long-term ureteral stenting 总被引:1,自引:0,他引:1
Internal double-J ureteral stents were designed from a urine-compatible polymer (C-Flex), and 35 stents were placed in patients. The overall patency rate for the stents was 80%, with most stent failures occurring before 2 months; the follow-up period ranged from 2 to 16 months, with a mean follow-up for all stents of 5.0 months. Stents were considered patent at last follow-up only if they had been in place for at least 2 months. No migration or fracture of the stents occurred. Physical properties of urine-exposed stents were compared with those of virgin tubing and tubing exposed for 1 year to shelf conditions. Stent patency was optimized by increasing urine flow by increasing the patient's voluntary oral intake, administering prophylactic oral antibiotics, and avoiding placement of stents into grossly bloody or infected collecting systems. 相似文献
58.
Based on the dissection of 30 hemi-mandibles, the authors report a study of the inferior alveolar artery in its intraosseous course. On morphologic considerations they propose a classification of the collaterals into two groups: the principal collaterals destined for the teeth and the bony alveolar tissue and the secondary collaterals destined for the sheath and the nerve as well as the bony tissue around the canal. Loss of the teeth and absorption of the alveolar bone modify the caliber of the inferior alveolar arterial axis, the distribution of its collaterals and possibly its mode of termination. These facts suggest a consideration of the vascularization of the mandible in terms of four sectors. They arrive at practical conclusions that may be drawn from this study in stomatology. 相似文献
59.
In this case, a male patient presented with a clinically and radiographieally unstable slipped capital femoral epiphysis (SCFE) as well as slipped calcaneal epiphysis years. Subsequent thorough at the age of 23 work-up revealed that he had some features of rickets and labo- ratory test demonstrated he had hypophos- phatemia (2.3mg/dl), normocalcemia, normal vi- tamin D metabolite levels, and secondary hy- perparathyroidism. 相似文献
60.
ER Brown KA Charles SA Hoare RL Rye DI Jodrell RE Aird R Vora U Prabhakar M Nakada RE Corringham M DeWitte C Sturgeon D Propper FR Balkwill JF Smyth 《Annals of oncology》2008,19(7):1340-1346
BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response. 相似文献