全文获取类型
收费全文 | 53569篇 |
免费 | 4565篇 |
国内免费 | 1646篇 |
专业分类
耳鼻咽喉 | 623篇 |
儿科学 | 648篇 |
妇产科学 | 1130篇 |
基础医学 | 8302篇 |
口腔科学 | 1451篇 |
临床医学 | 4493篇 |
内科学 | 10218篇 |
皮肤病学 | 1017篇 |
神经病学 | 3847篇 |
特种医学 | 1739篇 |
外国民族医学 | 6篇 |
外科学 | 7490篇 |
综合类 | 4198篇 |
现状与发展 | 1篇 |
一般理论 | 5篇 |
预防医学 | 3103篇 |
眼科学 | 1393篇 |
药学 | 4901篇 |
中国医学 | 825篇 |
肿瘤学 | 4390篇 |
出版年
2023年 | 204篇 |
2022年 | 264篇 |
2021年 | 569篇 |
2020年 | 374篇 |
2019年 | 661篇 |
2018年 | 1183篇 |
2017年 | 912篇 |
2016年 | 898篇 |
2015年 | 1010篇 |
2014年 | 1331篇 |
2013年 | 1642篇 |
2012年 | 2229篇 |
2011年 | 2154篇 |
2010年 | 1303篇 |
2009年 | 1282篇 |
2008年 | 1901篇 |
2007年 | 2025篇 |
2006年 | 1876篇 |
2005年 | 1553篇 |
2004年 | 1439篇 |
2003年 | 1464篇 |
2002年 | 1355篇 |
2001年 | 4722篇 |
2000年 | 4598篇 |
1999年 | 3932篇 |
1998年 | 1384篇 |
1997年 | 1012篇 |
1996年 | 625篇 |
1995年 | 510篇 |
1994年 | 463篇 |
1993年 | 421篇 |
1992年 | 1941篇 |
1991年 | 1692篇 |
1990年 | 1539篇 |
1989年 | 1496篇 |
1988年 | 1303篇 |
1987年 | 1204篇 |
1986年 | 1076篇 |
1985年 | 905篇 |
1984年 | 593篇 |
1983年 | 471篇 |
1982年 | 250篇 |
1981年 | 184篇 |
1980年 | 141篇 |
1979年 | 285篇 |
1978年 | 82篇 |
1974年 | 84篇 |
1973年 | 101篇 |
1972年 | 81篇 |
1970年 | 75篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
对17例人工绝育后曾行输卵管复通手术失败病例,进行再次显微输卵管复通手术,经随访二年以上,宫内妊娠率41.18%(7/17)。手术后成功率与输卵管吻合部位有关,峡部与壶腹部吻合效果最差。作者指出再次显微输卵管吻合手术对由于原吻合部位闭锁病例有一定的价值。但需慎重考虑如何提高初次吻合术质量、防止术后粘连是十分重要。 相似文献
73.
F X Pi-Sunyer 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):292-294
There are several possible determinants of obesity, including impaired thermogenesis and the differential utilization of fuels in different tissues. Whereas hypometabolism may initiate obesity in some people, once obese, individuals tend to manifest a higher resting metabolic rate because of their greater fat-free mass, exhibit an impaired thermic response to food, and expend more calories than lean individuals for equivalent amounts of activity. As a result, over a 24-h period, obese people generally expend more energy than lean people. A second determinant of obesity is related to fuel utilization and suggests that those predisposed to be obese may have an innate insulin resistance in muscle, leading to decreased uptake, oxidation, and storage of glucose in this tissue. As a result, the glucose is shunted to adipose tissue, where it is stored. With regard to treatment of obesity, emphasis on increased energy expenditure through the inclusion of reasonable amounts of activity is essential. However, this must always be combined with restraint in caloric intake. 相似文献
74.
75.
O Jegaden X Martin F Canton A Gelet J M Dubernard 《Journal des maladies vasculaires》1987,12(4):315-318
Sixteen patients underwent surgical treatment for severe renovascular hypertension with rapidly progressive renal failure. These patients were assessed preoperatively with the measurement of serum creatinine and blood-urea levels (means 271 +/- 204 mumol/l and 15.6 +/- 10.3 mmol/l respectively), and renal clearances. 5 patients underwent aorto-renal bypass (bilateral in one case) and 11 patients were treated by autotransplantation of the kidney. Operative mortality was 6.2%. Early results were assessed at 1 and 6 months postoperatively. Renal function was normal in 8 patients, improved in 5 (p less than 0.05), unchanged in 1 and worse in 1 by aorto-renal bypass thrombosis. At long-term with a minimum follow-up of 12 months (mean 31 +/- 12 months), the initial improvement in renal function remained steady in 12 patients whilst 1 patient has gone on to hemodialysis. At middle and long-term, 81% of the patients were normotensive without medication or had improved blood pressure (p less than 0.001). These good results confirm the reversibility of renal ischemic lesions and support an aggressive attitude towards the use of revascularization in the surgical treatment of such patients with renovascular hypertension and renal failure. 相似文献
76.
The cardiotoxic effects of hydralazine and prenalterol, given alone and in combination, were assessed in rats and rabbits. Acute myocardial necrosis was induced by a single administration of each drug alone in rats. However, the incidence and severity of lesions were markedly enhanced when both drugs were given in combination. Rats that received the same treatment for 10 consecutive days showed minimal or no acute necrosis, demonstrating the development of a resistance to further cardiotoxic effects of the drugs. Rabbits showed only minimal lesions when either drug was used alone and no enhancement of lesions when they were given in combination. From these data, it is concluded that the possibility of a cardiotoxic interaction exists when these drugs are used in combination and that the heavy rat (500-600 g) is a more sensitive model than the rabbit for studies of this nature. 相似文献
77.
78.
痔组织弹性纤维退变和血管生成的机制及其意义 总被引:13,自引:0,他引:13
目的研究痔组织弹性纤维的病理变化及微血管密度(MVD)和血管生成相关蛋白的表达与痔形成的关系。方法利用免疫组织化学染色技术(SP法),对比研究24例Ⅲ度痔患者的正常肛垫和痔两种组织内弹性纤维和MVD的变化,并检测一氧化氮合酶(NOS)的3种亚型、血管内皮生长因子(VEGF)和金属基质蛋白酶(MMP)2、MMP9在两种组织中表达的差异。结果痔组织存在显著的新生血管形成,痔组织与相对正常肛垫组织间的MVD计数、VEGF、MMP9表达差异存在统计学意义(P<0.05)。痔组织中iNOS明显增高,但与正常肛垫组织比较,不具备统计学意义;痔组织弹性纤维出现断裂、扭曲、变形、玻璃样变等异常,而正常肛垫组织中弹性纤维形态较规则、密集,断裂和变形少见。结论新生血管形成可能是痔的发病机制之一;MMP9对肛垫纤维支持结构的直接降解作用可能是痔形成和加重的一个重要机制;痔组织中iNOS表达增高还提示炎症因素和一氧化氮可能参与了痔的病理过程。 相似文献
79.
80.
Chai Ben-Fu柴本甫Shanghai Institute of Traunatology Orthopedics ShanghaiTang Xue-ming汤雪明Shanghai Second Medical College Shanghai 《中华医学杂志(英文版)》1986,99(2):126-132
Transmission electron microscopic investigation
of standardized fractures of radii in 50 rabbits re
vealed that fibroblasts took part in the formation of
bony callus. The osteogenetic role played by the
fibroblasts can be categorized into the following 5
aspects: a. Fibroblasts synthesize and secrete Type
collagen fibrils and induce deposition of calcium
salt crystals in the collagen fibrils. b. Fibroblasts
produce matrix vesicles in their surroundings. These
matrix vesicles become calcified and turn into floccu-
lent calcospherules which coalesce and fuse into bone
tissues. c. Fibroblasts harbor calcium granules in
their mitochondria, thus providing calcium for calci-
fication of the intercellular matrix and bone forma
tion between the cells. d. Fibroblasts can transform
directly into osteocytes; there is bone formation
around the fibroblasts, the bone tissues surround the
fibroblast in the form of bony lacuna, then the fibro-
blast in the lacuna transforms into osteocyte. e.
Fibroblasts can undergo degenerative changes leading
to decease and replacement by bone tissues. 相似文献