全文获取类型
收费全文 | 97261篇 |
免费 | 6557篇 |
国内免费 | 1150篇 |
专业分类
耳鼻咽喉 | 795篇 |
儿科学 | 2723篇 |
妇产科学 | 2467篇 |
基础医学 | 12317篇 |
口腔科学 | 1900篇 |
临床医学 | 9282篇 |
内科学 | 21705篇 |
皮肤病学 | 1660篇 |
神经病学 | 10366篇 |
特种医学 | 2944篇 |
外国民族医学 | 2篇 |
外科学 | 11045篇 |
综合类 | 2488篇 |
现状与发展 | 1篇 |
一般理论 | 63篇 |
预防医学 | 8278篇 |
眼科学 | 1328篇 |
药学 | 7102篇 |
8篇 | |
中国医学 | 1061篇 |
肿瘤学 | 7433篇 |
出版年
2024年 | 138篇 |
2023年 | 1115篇 |
2022年 | 2263篇 |
2021年 | 3951篇 |
2020年 | 2436篇 |
2019年 | 3062篇 |
2018年 | 3470篇 |
2017年 | 2475篇 |
2016年 | 2709篇 |
2015年 | 3183篇 |
2014年 | 4003篇 |
2013年 | 5032篇 |
2012年 | 7415篇 |
2011年 | 7484篇 |
2010年 | 4051篇 |
2009年 | 3629篇 |
2008年 | 5735篇 |
2007年 | 5695篇 |
2006年 | 5344篇 |
2005年 | 4983篇 |
2004年 | 4474篇 |
2003年 | 3932篇 |
2002年 | 3447篇 |
2001年 | 1639篇 |
2000年 | 1510篇 |
1999年 | 1462篇 |
1998年 | 830篇 |
1997年 | 611篇 |
1996年 | 588篇 |
1995年 | 463篇 |
1994年 | 392篇 |
1993年 | 344篇 |
1992年 | 752篇 |
1991年 | 640篇 |
1990年 | 606篇 |
1989年 | 611篇 |
1988年 | 509篇 |
1987年 | 461篇 |
1986年 | 445篇 |
1985年 | 350篇 |
1984年 | 310篇 |
1983年 | 259篇 |
1982年 | 157篇 |
1981年 | 141篇 |
1979年 | 230篇 |
1978年 | 144篇 |
1977年 | 135篇 |
1974年 | 127篇 |
1973年 | 133篇 |
1972年 | 130篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
P L Di Patre 《Medical hypotheses》1991,34(2):165-170
A theory is presented here in the attempt to explain why Alzheimer's disease (AD) primarily affects areas of the human brain that have been acquired recently in phylogenesis. Disturbances in cytoskeletal function are proposed to play a fundamental role in triggering the sequence of pathologic events leading to the occurrence of AD-related histopathological markers and to the degeneration and death of neurons. These deficits are supposed to occur more likely in neuronal populations that possess a high degree of plasticity, the substrate of memory functions, and that constitute, in fact, the phylogenetically new telencephalic regions of the human brain. 相似文献
62.
63.
Nutritional follow-up after total gastrectomy 总被引:1,自引:0,他引:1
64.
For the past 10 years the alfa-hydroxyacids and the bovine collagen injection have been used for peeling and the correction of multiple skin diseases. Until now, such progressive achievement has occurred in separate parallels just like the indications that have been held distinct. However, the studies carried out in order to clarify the mechanical action of the two substances have shown a common and fundamental denominator: the stimulation of synthesis of the new collagen in the patient's skin. On the basis of these results and the existence of common clinical indications of the use of glycolic acid and collagen, the authors have worked out a protocol involving a combined and contemporary application in progressive steps. They developed the rationales of such protocol and analyzed the results of its application on a number of carefully selected patients for a clinical comparison and on a sample of rats for a histological comparison. They have concluded that the contemporary use of glycolic acid and bovine collagen is a simple and safe method whose synergy action leads to more intense and long-lasting effects than the ones observed in the isolated application of the two substances. The authors have also obtained interesting and significant histological results. 相似文献
65.
Daily nutrient intake represents a modifiable determinant of nutritional status in chronic haemodialysis patients. 总被引:2,自引:0,他引:2
Vincenzo Bellizzi Biagio R Di Iorio Vincenzo Terracciano Roberto Minutolo Carmela Iodice Luca De Nicola Giuseppe Conte 《Nephrology, dialysis, transplantation》2003,18(9):1874-1881
BACKGROUND: In maintenance haemodialysis patients, daily food intake is changeable; however, its relationship with nutritional status is unexplored. This study aimed to evaluate the isolated, long-term effect of daily nutrient intake on nutritional status in haemodialysis patients. METHODS: We performed a prospective 1-year controlled study in 27 chronic haemodialysis patients, without recognized risk factors for malnutrition. Each day for 1 week, four times in the year, we measured protein nitrogen appearance, and assessed dietary protein (DPI) and energy (DEI) intake from dietary diaries. We compared the nutritional outcome of patients spontaneously reducing nutrient intake below the threshold of 0.8 g/kg body weight/day for DPI and 25 kcal/kg body weight/day for DEI during the week (LOW, n = 8), with controls at adequate nutrient intake (CON, n = 19). An interventional 6-month study was then carried out in LOW to verify the cause-effect relationship. RESULTS: All patients showed a day-by-day reduction of whole nutrient intake during interdialytic period, which was mostly relevant in the third interdialytic day (L3). During the 1-year study, even in the presence of adequate dialysis dose and normal inflammatory indexes, body weight (68.0 +/- 5.5 to 65.8 +/- 5.9 kg), serum albumin (3.96 +/- 0.07 to 3.66 +/- 0.06 g/dl) and creatinine (9.2 +/- 1.1 to 8.1 +/- 0.7 mg/dl) significantly decreased in LOW but not in CON. Diaries evidenced in LOW a reduced number of meals at L3 that was explained by the fear of excessive interdialytic weight gain. During the interventional study, daily DPI and DEI increased at L3; this was associated with a significant increment of body weight, and serum albumin and creatinine levels. CONCLUSIONS: In maintenance haemodialysis patients the persistent, marked reduction of daily nutrient intake, even if limited to a single day of the week, is an independent determinant of reversible impairment of nutritional status. 相似文献
66.
Ultrafiltration and solute transport during 60-min peritoneal dialyses of normal rabbits with intraperitoneal administration of phosphatidylcholine were compared to control values. The ultrafiltration rate of 0.27 mL/Kg/min did not increase when phosphatidylcholine was added. This agent had no effect on the ultrafiltration coefficient, sodium mass transport or solute clearances. Previously reported beneficial results with this agent could be due to repletion of a deficiency or an effect of the organic solvent. More studies of safety and efficacy of phosphatidylcholine are warranted before widespread clinical use. 相似文献
67.
68.
69.
70.
Sir, We are writing to provide some clarifications on the EditorialComment by Drüeke et al. [1]. We would have been happyto provide these very same clarifications had we been fairlyinvited to do so before the publication of the article. First of all, we would like to 相似文献