全文获取类型
收费全文 | 3659篇 |
免费 | 391篇 |
国内免费 | 208篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 60篇 |
妇产科学 | 22篇 |
基础医学 | 590篇 |
口腔科学 | 34篇 |
临床医学 | 484篇 |
内科学 | 685篇 |
皮肤病学 | 73篇 |
神经病学 | 267篇 |
特种医学 | 128篇 |
外国民族医学 | 1篇 |
外科学 | 405篇 |
综合类 | 326篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 290篇 |
眼科学 | 103篇 |
药学 | 284篇 |
中国医学 | 131篇 |
肿瘤学 | 353篇 |
出版年
2024年 | 7篇 |
2023年 | 81篇 |
2022年 | 168篇 |
2021年 | 166篇 |
2020年 | 129篇 |
2019年 | 136篇 |
2018年 | 127篇 |
2017年 | 100篇 |
2016年 | 113篇 |
2015年 | 159篇 |
2014年 | 180篇 |
2013年 | 162篇 |
2012年 | 253篇 |
2011年 | 283篇 |
2010年 | 165篇 |
2009年 | 181篇 |
2008年 | 226篇 |
2007年 | 208篇 |
2006年 | 225篇 |
2005年 | 185篇 |
2004年 | 115篇 |
2003年 | 120篇 |
2002年 | 102篇 |
2001年 | 73篇 |
2000年 | 53篇 |
1999年 | 68篇 |
1998年 | 58篇 |
1997年 | 40篇 |
1996年 | 43篇 |
1995年 | 38篇 |
1994年 | 22篇 |
1993年 | 17篇 |
1992年 | 41篇 |
1991年 | 18篇 |
1990年 | 31篇 |
1989年 | 27篇 |
1988年 | 22篇 |
1987年 | 19篇 |
1986年 | 15篇 |
1985年 | 19篇 |
1984年 | 8篇 |
1983年 | 10篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1966年 | 2篇 |
排序方式: 共有4258条查询结果,搜索用时 36 毫秒
41.
Nguyen Minh Hai Nguyen Dang Dung Dinh Cong Pho Vu Tung Son Vu Ngoc Hoan Phan Tan Dan Bui Dang The Anh La Huong Giang Pham Ngoc Hung 《Vaccine》2021,39(7):1140-1147
BackgroundROTAVAC® is derived from human 116E rotavirus (RV) neonatal strain. In this study, we evaluated the immunogenicity, safety and reactogenicity of ROTAVAC® in Vietnam.MethodWe conducted a phase IV clinical trial in healthy infants aged 6–8 weeks using the complete regimen of ROTAVAC® with three doses. Serum anti-RV IgA was measured by enzyme-linked immunosorbent assay to assess the geometric mean concentration in infants who received the complete regimen of the vaccine.ResultsA total of 360 participants were enrolled in this clinical trial. The mean age ± standard deviation at enrollment was 6.9 ± 0.6 weeks. The anti-RV IgA titer was 4.01 ± 3.74 mg/ml pre-vaccination and substantially increased to 29.27 ± 80.64 mg/ml post-vaccination. The value of logIgA significantly increased (p = 0.003) from 0.28 ± 0.79 to 1.03 ± 0.54. The proportion of participants with equal to and greater than 3-fold and 4-fold shifts in pre- to post-vaccination antibody titer (IgA) were 55.4% and 48.3%, respectively. No adverse events or serious adverse events were recorded immediately within 30 min after the administration of each dose. The most common adverse events within 14 days after each visit were fever, unusual crying and irritability. Other adverse events occurred at a low rate, and no case of intussusception was noted.ConclusionsThe complete regimen of ROTAVAC® demonstrated an immunological response with clinically acceptable safety profile. Post-completion of this study, ROTAVAC® is now a WHO-prequalified vaccine and available in Vietnam. 相似文献
42.
目的研发一种专用于防旋型股骨近端髓内钉置入时的三维导航器。方法选取颈干角为(135±5)°,并且股骨大转子顶点基本与股骨头中心等高的人体股骨骨骼的干标本32例,其中左侧16例,右侧16例。通过股骨头中心、平行于股骨干、垂直于股骨干与股骨颈所在的平面用钢锯将股骨标本的股骨头进行截骨;在股骨大粗隆顶端开口向股骨近端髓腔内插入PFNA主钉,主钉钉尾与股骨头中心点在同一高度上。在本课题所研发的股骨近端髓内钉三维导航器的导引下向股骨头颈部打入动力钉导引针,测量动力钉导引针在股骨头截骨面上的出针点与经股骨头中心点直线的垂直距离作为偏离值。结果利用本课题所研制的三维立体导航器在32例股骨骨骼的干标本上置入导引针,其中14例偏离值为0(占43.75%),最大偏离值为2mm,仅3例(占9.375%),平均误差只有0.69mm。结论本课题所研制的导航器结构简单,操作简便,定位精确,值得进一步在临床上研究应用。 相似文献
43.
L X Dang D A Pearlman P A Kollman 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(12):4630-4634
We have carried out free energy perturbation calculations on DNA double-stranded hexanucleotides. The sequence d(CGCGCG)2 has been "mutated" into d(CGTGCG).d(CGCACG) with the oligonucleotide in the A, B, and Z structural forms, both in vacuo and in aqueous solution. In addition, model free energy calculations have been carried out in which the electrostatic charges of the H-bonding groups of the bases in the major and minor grooves of the DNA are reduced to zero as a way of assessing the relative solvation effects of these groups in the different structural forms of DNA. Finally, energy component analyses have been carried out to assess the relative roles of different intranucleotide interactions on the B----Z equilibrium as a function of base sequence. In vacuo, the free energy for changing a G.C to an A.T base pair is largest in the Z conformation; in the A and B conformations, the free energy cost is approximately 2 kcal/mol lower (1 cal = 4.184 J). The results are similar when the simulations are run in explicit solvent: the change costs 3 kcal/mol more in the Z conformation than in the B form. These results are consistent with experimental data, where it is clear that A.T sequences are significantly more "Z-phobic" than G.C sequences. The calculations indicate that both intranucleotide and solvation interactions contribute to this Z-phobicity. 相似文献
44.
45.
46.
E R Guinto A Vindigni Y M Ayala Q D Dang E Di Cera 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(24):11185-11189
Residues energetically linked to the allosteric transition of thrombin from its anticoagulant slow form to the procoagulant fast form have been identified by site-directed mutagenesis. The energetics of recognition by the two forms of the enzyme were probed by using a synthetic chromogenic substrate, fibrinogen, and hirudin. The thrombin residues E39, W60d, E192, D221, and D222 are linked to the slow-->fast transition and are part of an "allosteric core" through which events originating at the Na+ binding loop propagate to other regions of the enzyme. The thrombin residues Y76, W96, W148, and R173 lie at the periphery of the allosteric core, affect recognition of fibrinogen and hirudin to the same extent in both forms, and are not linked to the slow-->fast transition. 相似文献
47.
48.
49.
目的 探讨CT征象、GCS评分、瞳孔变化、手术时机、血压、年龄、血糖、血白细胞计数和并发症对96例急性硬膜下血肿手术患者预后因素的影响。方法 对我科96例急性硬膜下血肿手术患者预后影响因素进行回顾性分析。结果 按COS标准,恢复良好46.9%,中度残疾9.4%,重度残疾6.3%,持续性植物生存5.2%,死亡32.2%。结论 CT征象、GCS评分、瞳孔变化、手术时机、血压、年龄、血糖、血白细胞和并发症是评价急性硬膜下血肿预后的可靠指标。及时、正确清除血肿,标准去骨瓣减压,维持正常血压,控制血糖和防治并发症,能有效改善急性硬膜下血肿患者预后,也是降低患者死残率的最有效措施。 相似文献
50.
Phase II study of denileukin diftitox for relapsed/refractory B-Cell non-Hodgkin's lymphoma. 总被引:1,自引:0,他引:1
Nam H Dang Fredrick B Hagemeister Barbara Pro Peter McLaughlin Jorge E Romaguera Dan Jones Barry Samuels Felipe Samaniego Anas Younes Michael Wang Andre Goy Maria A Rodriguez Pamela L Walker Yolanda Arredondo Ann T Tong Luis Fayad 《Journal of clinical oncology》2004,22(20):4095-4102
PURPOSE: Denileukin diftitox is a fusion protein combining diphtheria toxin and interleukin-2 (IL-2) that targets tumor cells expressing the IL-2 receptor. Its efficacy has been shown in CD25+ cutaneous T-cell lymphoma, but not in B-cell non-Hodgkin's lymphoma (NHL). A phase II study was performed to evaluate the efficacy and tolerability of denileukin diftitox for relapsed or refractory B-cell NHL. PATIENTS AND METHODS: Patients with relapsed or refractory B-cell NHL were eligible. Tumor CD25 expression was determined by immunohistochemistry or flow cytometry. Denileukin diftitox was administered intravenously at a dose of 18 microg/kg once daily for 5 days every 3 weeks, up to eight cycles. RESULTS: Of the 45 patients assessable for response, 32 (71%) were refractory to the last chemotherapy treatment, and all were previously treated with rituximab. Three complete responses (6.7%) and eight partial responses (17.8%) were observed, for an overall response rate of 24.5%. Nine patients (20%) had stable disease. Objective response rates were similar in CD25+ (22%) and CD25- histologies (29%), as were stable disease rates (22% and 18%, respectively). For responding patients, the median time to treatment failure was 7 months, with a median follow-up in survivors of 18 months (range, 9 to 28 months), and the projected progression-free survival at 20 months was 24% (95% CI, 0% to 60%). Most toxicities were low-grade and transient. CONCLUSION: Denileukin diftitox seems to be effective in relapsed or refractory, CD25+ and CD25- B-cell NHL and is well-tolerated at the dosage evaluated. Evaluation of denileukin diftitox in combination with other agents may be warranted. 相似文献