全文获取类型
收费全文 | 2894717篇 |
免费 | 243736篇 |
国内免费 | 12879篇 |
专业分类
耳鼻咽喉 | 39878篇 |
儿科学 | 91507篇 |
妇产科学 | 72858篇 |
基础医学 | 477222篇 |
口腔科学 | 77570篇 |
临床医学 | 259502篇 |
内科学 | 493065篇 |
皮肤病学 | 82379篇 |
神经病学 | 248760篇 |
特种医学 | 113191篇 |
外国民族医学 | 88篇 |
外科学 | 455592篇 |
综合类 | 88426篇 |
现状与发展 | 23篇 |
一般理论 | 2097篇 |
预防医学 | 248026篇 |
眼科学 | 66105篇 |
药学 | 195516篇 |
22篇 | |
中国医学 | 8540篇 |
肿瘤学 | 130965篇 |
出版年
2022年 | 22743篇 |
2021年 | 54356篇 |
2020年 | 34682篇 |
2019年 | 57609篇 |
2018年 | 69650篇 |
2017年 | 52956篇 |
2016年 | 58186篇 |
2015年 | 72892篇 |
2014年 | 106899篇 |
2013年 | 171852篇 |
2012年 | 74744篇 |
2011年 | 72884篇 |
2010年 | 112053篇 |
2009年 | 117570篇 |
2008年 | 60642篇 |
2007年 | 61500篇 |
2006年 | 73161篇 |
2005年 | 68921篇 |
2004年 | 71263篇 |
2003年 | 62578篇 |
2002年 | 52880篇 |
2001年 | 73937篇 |
2000年 | 66033篇 |
1999年 | 71552篇 |
1998年 | 61897篇 |
1997年 | 60390篇 |
1996年 | 58188篇 |
1995年 | 53676篇 |
1994年 | 47835篇 |
1993年 | 44797篇 |
1992年 | 47875篇 |
1991年 | 46237篇 |
1990年 | 43857篇 |
1989年 | 43854篇 |
1988年 | 40732篇 |
1987年 | 39915篇 |
1986年 | 37954篇 |
1985年 | 38845篇 |
1984年 | 38518篇 |
1983年 | 36067篇 |
1982年 | 38094篇 |
1981年 | 36341篇 |
1980年 | 34350篇 |
1979年 | 30915篇 |
1978年 | 29745篇 |
1977年 | 27750篇 |
1976年 | 25487篇 |
1975年 | 24148篇 |
1974年 | 23868篇 |
1973年 | 22649篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Normal seminal vesicles were studied histologically in 80, and by Feulgen’s cytophotometric method in 10 autopsied cases (males,
44–82 years of age). In every case large, hyperchromatic nuclei were found. By cytophotometry euploid polyploid atypia was
also shown in every case, which is characteristic of benign hormonal dysplasia. 相似文献
994.
The hepatotropic effect of nonsteroidal anti-inflammatory drugs (NSAID) such as indomethacin, voltaren, piroxicam, phenylbutazon, mefenamic acid was studied. It was found that according to their level of the pharmacological protection of the liver against tetrachlormethan these agents may be arranged in the following sequence: mefenamic acid, phenylbutazon, voltaren, piroxicam. The hepatoprotective effect of NSAID correlates with the antioxidant properties and fails to correlate with the antioxidant ones. The hepatotoxic effect of NSAID was determined by their ability to suppress synthesis of prostaglandins. 相似文献
995.
996.
Lester A. Klein 《Neurourology and urodynamics》1987,6(2):95-99
The trigone sensitivity test, a complementary test to cystometry, has been proposed as a method for distinguishing certain clinical disorders. Pressure is applied to the trigone region of the bladder by pulling upon a Foley catheter with the balloon inflated and the amount of force needed to induce an urge to void is recorded. Although the trigone sensitivity test has been proposed as a test of exteroceptive function, it is possible that deeper receptors, perhaps proprioceptors, are actually responsible for the awareness of the urge to void during the study. The present investigation compared the trigone sensitivity test with provoked detrusor contraction in 107 patients. The findings indicate that variations in the two responses occur independently of each other. It is concluded that different neural pathways are responsible for the two functions. The hypothesis that exteroceptive and not proprioceptive nerves are being measured during trigone sensitivity testing is supported by these findings. 相似文献
997.
N.B.SIMPSON 《The British journal of dermatology》1987,117(1):43-47
Sebum excretion rate was measured by a photometric technique. We demonstrated a high correlation between sebum excretion rates on the left and right sides of the upper back and between back and forehead skin. Sebum excretion rate measurements overlying an open comedone (blackhead) were significantly lower than those obtained from normal skin. This observation demonstrates a functional obstruction to the outflow of sebum and would suggest that the lack of involvement of open comedones in inflammatory acne is not because of the maintenance of a free flow of sebum. 相似文献
998.
999.
1000.
G H Ballantyne M J Zdon D E Schafer G R Fratesi J R Roberts M Tyshkov I M Modlin 《Annals of surgery》1986,204(5):559-565
The cellular mechanisms by which pepsinogen (PNG) secretion is controlled are not understood. The aim of this study was to explore whether modulation of PNG secretion is mediated by cAMP or calcium-calmodulin (C-C). PNG secretion in isolated rabbit gastric fundic glands (IGG) was tested, using agents believed to act via cAMP or C-C. IGG were stimulated for 30 minutes with histamine (H) 10(-5) M, isoproterenol (I) 10(-5) M, carbachol (C) 10(-5) M, cholecystokinin-octapeptide (CCK-8) 10(-7) M, forskolin (F) 10(-5) M, 8 bromo-cAMP (8B) 10(-3) M, and A23187 (A) 10(-6) M. PNG levels were determined by spectrophotometric assay of hemoglobin digestion products. PNG amounts secreted were (mean per cent above basal levels of total IGG PNG units +/- SEM): H, -0.02 +/- 0.30%; I, 3.5 +/- 0.9%; C, 5.1 +/- 2.2%; CCK-8, 5.3 +/- 1.5%; F, 10.6 +/- 3.8%; 8B, 13.8 +/- 4.5%; A, 2.1 +/- 1.1%. All secretagogues except H stimulated PNG release significantly above basal levels (p less than 0.05). A primary histaminergic mechanism for pepsinogen secretion is unlikely. Since two other adenylate cyclase activators, isoproterenol and forskolin and the 3':5'-cyclic adenosine monophosphate analog 8-bromo cAMP stimulated pepsinogen secretion, cAMP-dependence is probable. Since carbachol, CCK-8, and A23187, which are believed to act via calcium-calmodulin, also stimulated pepsinogen secretion, this system, too, presumably plays a substantial role. Thus the data support a dual 3':5'-cyclic adenosine monophosphate/calcium-calmodulin modulation of pepsinogen secretion. 相似文献