全文获取类型
收费全文 | 46189篇 |
免费 | 3819篇 |
国内免费 | 3043篇 |
专业分类
耳鼻咽喉 | 386篇 |
儿科学 | 727篇 |
妇产科学 | 740篇 |
基础医学 | 5689篇 |
口腔科学 | 722篇 |
临床医学 | 5980篇 |
内科学 | 7605篇 |
皮肤病学 | 603篇 |
神经病学 | 2881篇 |
特种医学 | 1412篇 |
外国民族医学 | 17篇 |
外科学 | 5207篇 |
综合类 | 6769篇 |
现状与发展 | 5篇 |
一般理论 | 7篇 |
预防医学 | 2747篇 |
眼科学 | 1271篇 |
药学 | 4502篇 |
31篇 | |
中国医学 | 1857篇 |
肿瘤学 | 3893篇 |
出版年
2024年 | 141篇 |
2023年 | 668篇 |
2022年 | 1712篇 |
2021年 | 2189篇 |
2020年 | 1595篇 |
2019年 | 1539篇 |
2018年 | 1597篇 |
2017年 | 1373篇 |
2016年 | 1281篇 |
2015年 | 1920篇 |
2014年 | 2394篇 |
2013年 | 2160篇 |
2012年 | 3366篇 |
2011年 | 3613篇 |
2010年 | 2110篇 |
2009年 | 1718篇 |
2008年 | 2554篇 |
2007年 | 2605篇 |
2006年 | 2436篇 |
2005年 | 2458篇 |
2004年 | 1729篇 |
2003年 | 1632篇 |
2002年 | 1336篇 |
2001年 | 1105篇 |
2000年 | 1124篇 |
1999年 | 1230篇 |
1998年 | 659篇 |
1997年 | 717篇 |
1996年 | 539篇 |
1995年 | 482篇 |
1994年 | 416篇 |
1993年 | 299篇 |
1992年 | 367篇 |
1991年 | 320篇 |
1990年 | 271篇 |
1989年 | 238篇 |
1988年 | 219篇 |
1987年 | 188篇 |
1986年 | 170篇 |
1985年 | 123篇 |
1984年 | 70篇 |
1983年 | 78篇 |
1982年 | 48篇 |
1981年 | 53篇 |
1980年 | 31篇 |
1979年 | 45篇 |
1978年 | 20篇 |
1977年 | 18篇 |
1974年 | 18篇 |
1973年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
J-L Chabernaud 《Archives de pédiatrie》2005,12(4):477-490
The need for resuscitation of a distressed newborn in delivery room is more and more easily predictable. The two principal reasons are improvement of obstetrical survey and best perinatal regionalisation. Perinatal asphyxia and premature labour, especially before 32 weeks of gestational age, are the more frequent situation needing resuscitation at birth. A good survey of pregnancy and labor, verification of availability and efficiency of care devices and material in the delivery room are essential. In all guidelines respiratory resuscitation is today the priority in the first minutes. Non invasive positive pressure ventilation and early use of exogenous surfactant are the recent advances for the care of very premature baby in delivery room. Having a neonatal ventilator and pulse oximetry monitoring is recommended and can improve results. For the pregnant woman and the baby, maternal transfer if no contra-indications exist and when it is possible, is preferred to postnatal transportation in case of very premature labor or high risk pregnancy. In all the other situations neonatal transport must be strictly organised and realised by well-trained pediatric team, with adapted material and in the best conditions for security and comfort. The goal is to prevent any rupture until arrival in the referring neonatal intensive car unit. 相似文献
44.
45.
有学者认为,所谓改革,就是在持续的摸索和尝试中不断调整步伐、不断自我修正的过程。医疗卫生领域的改革实践同样如此。 相似文献
46.
OBJECTIVE: Many patients with haemorrhoids are investigated because of the fear of missing colorectal cancer (CRC). The aim of this study was to determine whether a primarily clinical approach regarding the need for investigation was safe and did not miss patients with CRC. PATIENTS AND METHODS: Data was collected prospectively on 589 consecutive patients with the principle diagnosis of haemorrhoids at first clinic visit. All had clinical assessment including rigid sigmoidoscopy and were treated by phenol injection or banding. They were categorized for (1) no review unless symptoms persisted -'One Stop SOS' (2) outpatient review or (3) investigation. To check for the development of CRC they were contacted by postal questionnaire or telephone interview with a minimum of one year from diagnosis and treatment. All 589 patients were cross-referenced with the Pathology database and the Hospital Information Services System. RESULTS: Four hundred and sixty-nine (80%) answered the questionnaire; 352 patients (60% of the total group) fell in the 'one stop SOS' outpatient category; 95 (16%) patients were followed up to review response to treatment for large haemorrhoids; 105 (18%) were investigated with barium enema (12%), flexible sigmoidoscopy (4%), colonoscopy (1%) and miscellaneous (1%); 37 (6%) patients were either given a haemorrhoidectomy date or referred on with a different diagnosis. No patients selected for 'one-stop' treatment developed CRC. Five (0.8%) patients were diagnosed with CRC after appropriate investigation was instituted for suspicious symptoms. One patient with distal transverse colon cancer had a delayed diagnosis as she was investigated initially by flexible sigmoidoscopy. CONCLUSION: Most patients with the primary diagnosis of symptomatic haemorrhoids do not need investigation. 相似文献
47.
The acquisition of new food allergy after orthotopic liver transplantation is now a well described phenomenon, mainly reported in children. The etiology of this phenomenon is at present unclear, but has been ascribed by some to tacrolimus treatment. Here we report a case of liver transplant acquired food allergy (LTAFA) in a child who received a split liver graft. The case is remarkable for the absence of new food allergy in the adult recipient of the same graft. This suggests that host-specific factors play an important role in the development of food allergy after liver transplantation, and emphasizes the predisposition that children have toward this phenomenon. Possible mechanisms underlying the development of food allergy after liver transplantation are discussed. In conclusion, tacrolimus treatment alone cannot account for LTAFA. Host factors such as the maturity of immune regulatory mechanisms are likely to play a critical role in the development of new food allergy after a liver transplant. 相似文献
48.
49.
50.
Ⅰ、Ⅲ型前胶原基因第2外显子核酶对靶RNA的体外切割活性的研究 总被引:5,自引:0,他引:5
目的 体外研究锤头型α1Ⅰ型及Ⅲ型前胶原基因第2外显子片段核酶对各自靶RNA分子的切割活性及反应条件。同时观察两反义核酶对瘢痕中成纤维细胞胶原合成的影响。方法 将含α1Ⅰ型及Ⅲ型前胶原基因第2外显子片段的重组质粒(pT-Ⅰ、pT-Ⅲ),经体外^32P标记转录后形成产物靶RNA。同时将含特异性核酶基因的重组质粒(pT-gⅠ、pT-gⅢ)进行非标记的体外转录,产物(核酶)与各自的^32P-靶RNA按不同的条件混和反应,电泳后放射自显影观察结果。将构建好的核酶以脂质体包裹后导入培养的成纤维细胞内,采用图像分析法观察核酶对成纤维细胞Ⅰ型、Ⅲ型胶原蛋白mRNA合成的影响。结果 两种核酶在37℃、42℃均能有效切割各自的靶RNA,对Mg^2 浓度的要求范围较宽(10~20mmol/L);反应温度从65℃逐渐降至并维持在37℃的条件下核酶切割活性显提高。Ⅰ、Ⅲ型胶原蛋白mRNA的表达明显降低,胶原蛋白生成降低,胶原生成明显受抑制。结论 针对α1Ⅰ型及Ⅲ型前胶原基因第2外显子片段的核酶能有效地在体外对靶RNA进行切割并能有效地抑制瘢痕中成纤维细胞胶原的合成。 相似文献