全文获取类型
收费全文 | 8760篇 |
免费 | 614篇 |
国内免费 | 467篇 |
专业分类
耳鼻咽喉 | 50篇 |
儿科学 | 116篇 |
妇产科学 | 115篇 |
基础医学 | 835篇 |
口腔科学 | 292篇 |
临床医学 | 1078篇 |
内科学 | 1283篇 |
皮肤病学 | 89篇 |
神经病学 | 207篇 |
特种医学 | 289篇 |
外科学 | 1156篇 |
综合类 | 1861篇 |
现状与发展 | 1篇 |
一般理论 | 5篇 |
预防医学 | 625篇 |
眼科学 | 373篇 |
药学 | 692篇 |
33篇 | |
中国医学 | 622篇 |
肿瘤学 | 119篇 |
出版年
2024年 | 75篇 |
2023年 | 312篇 |
2022年 | 478篇 |
2021年 | 561篇 |
2020年 | 423篇 |
2019年 | 284篇 |
2018年 | 222篇 |
2017年 | 216篇 |
2016年 | 206篇 |
2015年 | 231篇 |
2014年 | 443篇 |
2013年 | 631篇 |
2012年 | 447篇 |
2011年 | 564篇 |
2010年 | 439篇 |
2009年 | 471篇 |
2008年 | 419篇 |
2007年 | 426篇 |
2006年 | 415篇 |
2005年 | 384篇 |
2004年 | 288篇 |
2003年 | 252篇 |
2002年 | 236篇 |
2001年 | 163篇 |
2000年 | 155篇 |
1999年 | 112篇 |
1998年 | 113篇 |
1997年 | 113篇 |
1996年 | 69篇 |
1995年 | 60篇 |
1994年 | 75篇 |
1993年 | 53篇 |
1992年 | 47篇 |
1991年 | 52篇 |
1990年 | 50篇 |
1989年 | 41篇 |
1988年 | 31篇 |
1987年 | 36篇 |
1986年 | 35篇 |
1985年 | 34篇 |
1984年 | 23篇 |
1983年 | 8篇 |
1982年 | 26篇 |
1981年 | 25篇 |
1980年 | 25篇 |
1979年 | 28篇 |
1978年 | 21篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1973年 | 4篇 |
排序方式: 共有9841条查询结果,搜索用时 31 毫秒
41.
Kenzi Takamura 《Ecotoxicology (London, England)》1995,4(4):245-257
The effect of the surfactant LAS was investigated on chironomid emergence using six outdoor artificial channels. The concentrations of LAS were mostly between 1 and 2 mgl-1 in the three treated channels. Chironomus yoshimatsui, Cricotopus tamapullus, Eukiefferiella coerescens, Eukiefferiella sp. and Thienemanniella majuscula were the major chironomids obtained with emergence traps. The number of midges trapped did not differ significantly between the treatment and the control for either of the species. On the other hand, the ratios of midges failing to emerge to the total midges trapped was significantly higher in the treatment than in the control for all of the species. The results show that chironomids emergence is difficult as a result of LAS treatment probably due to the lowered surface tension. 相似文献
42.
Mohammad H. Ebrahimzadeh MD Mohammad T. Rajabi MD 《The Journal of foot and ankle surgery》2007,46(6):429-433
Long-term clinical and functional outcomes for patients undergoing foot and ankle amputations are not well documented. We attempted to document long-term outcomes for patients who required lower extremity amputations as a result of wounds suffered during wartime. For this study, 27 Iranian soldiers who had wounds requiring amputation of the foot and ankle were selected for follow-up. The participants' wartime medical records were reviewed, a clinical examination was performed, and each participant completed a questionnaire. Postamputation follow-up averaged 17.5 years. The most prevalent (66.6%) cause of injury was a land mine. The prevalences of different clinical symptoms reported by the amputees at the time of the last follow-up were as follows: 11 (40.7%) with phantom sensation, 6 (22.2%) with phantom pain, 12 (44.4%) with stump pain, 12 (44.4%) with back pain, 9 (33.3%) with contralateral knee pain, and 4 (14.8%) with ipsilateral knee pain; 20 (74%) reported treatment for psychological conditions. In regard to social conditions, 13 (48.1) were currently employed, or had been employed, for a number of years after the amputation; 26 (96%) had children, and all of the patients were married. The results of this observational study indicate that individuals have significant long-term pain and discomfort after war-related lower extremity amputation. Although all 27 (100%) of the amputees were able to maintain satisfactory family functioning, only 13 (48.1%) of the study participants were able to remain productively employed after undergoing amputation, and 20 (74%) reported long-term psychological problems in addition to their physical pain. 相似文献
43.
Atrial fibrillation (AF) is the most common cardiac arrhythmia among the elderly. Its incidence increases dramatically with increasing age and decreasing left ventrieular function, peaking in subjects with overt congestive heart failure, Because of the unsatisfactory efficacy and possible serious side effects of clinically available anti-AF drugs for AF patients with sick sinus syndrome, pacing techniques have recently been applied in the treatment of AF. The cardiac pacemaker Vitatron 相似文献
44.
45.
46.
角蛋白人工腱膜预防全椎板切除术后硬脊膜黏连 总被引:2,自引:1,他引:1
[目的]探讨角蛋白(keratinsubstance,KS)人工腱膜材料用于预防全椎板切除术后硬脊膜黏连的效果。[方法]Wistar大白鼠60只,随机分3组,每组20只,咬除T。:全椎板,造成2rnrnX8rnlffl大小的椎板缺损,加入不同处理因素,A组:空白对照组;B组:人工腱膜组;C组:白体腱膜组。术后2、4、8,12周处死动物,各时间点大体观察采用Rydell瘢痕黏连程度评级标准评分。完整取出T。:节段,包括椎旁肌。经HE染色后,镜下组织学观察采用改良Nussbaum标准行评分。同时切取2,4、8、12周人工腱膜组硬膜外瘢痕组织进行透射电镜观察。所测数据行Kruskal—Wallis秩和检验,取a〈0.05作为统计显著差异的标准。[结果]KS人工腱膜材料无毒性和排异反应:A组的Rydell评分,改良Nussbaum评分高于B、C组(P〈0.05),B组C组比较无差别(P〉0.05)。B、C组与对照组比较,均能够明显减少椎板切除术后的硬膜外瘢痕形成。[结论]硬膜外瘢痕黏连主要来自硬膜后方的血肿和成纤维细胞(fibroblast,FB)的增殖。KS人工腱膜具有良好的组织相容性,无局部及全身的不良反应,具有良好物理屏障作用。将l(S人工腱膜放置在椎板缺损处,能够有效的防止纤维组织侵入椎管,预防硬膜外瘢痕黏连。在动物实验中,KS人工腱膜能够安全有效的预防椎板切除术后硬膜外瘢痕黏连。 相似文献
47.
目的 观察亚低温(33℃)对大鼠短暂性脑缺血后神经元的保护作用。方法 32只DS大鼠分为假手术组、常温缺血组和即刻亚低温组,采用尼氏体亚甲蓝特殊染色观察存活神经元、原位细胞凋亡检测法(TUNEL染色)检测及电镜观察脑缺血后大鼠CA1区神经元凋亡情况。结果 与假手术组相比,常温缺血组海马CA1区存活的锥体细胞数目减少(P<0.01);与常温缺血组相比,亚低温缺血组海马CA1区存活的锥体细胞数目明显增多(P<0.01)。亚低温缺血组大鼠海马CA1区TUNEL染色阳性细胞数目明显少于常温缺血组(P<0.01)。结论 脑缺血后迟发性神经元死亡很可能通过凋亡途径,亚低温对缺血后神经元的保护作用与减少神经元凋亡有关。 相似文献
48.
健康人格是个体身心顺利发展的重要保证,是大学生适应社会、充分发挥自己能力的心理基础。而目前许多高等医药院校在大学生健康人格培养方面,普遍重视不够。本文从学校、教师、失学生自身三个角度,试探索出一套适合高等医药院校大学生健康人格建立和发展的培养模式,以期为对以后的心理健康教育工作有一定的启发和指导作用。 相似文献
49.
目的探讨人工髓核置换治疗腰椎间盘突出症临床应用的初步效果. 方法自2002年5月~2003年8月行单个人工髓核假体(PDN)置换术治疗腰椎间盘突出症26例. 结果所有病例均获随访,平均时间10.5(3~18)个月.临床疗效评价:优18例,良4例,尚可2例.1例发生椎间隙感染,保守治疗后好转;1例术后2月出现假体移位、症状复发,行再次手术更换假体后治愈. 结论人工髓核假体置换治疗腰椎间盘突出症能恢复椎间隙高度,操作简单,创伤小,恢复快,近期疗效满意,远期疗效仍需进一步观察. 相似文献
50.
Neural classifier construction using regularization, pruning and test error estimation 总被引:1,自引:0,他引:1
Mads Hintz-Madsen Lars Kai Hansen Jan Larsen Morten With Pedersen Michael Larsen 《Neural networks》1998,11(9):1659-1670
In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems. 相似文献