全文获取类型
收费全文 | 7342篇 |
免费 | 465篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 101篇 |
儿科学 | 216篇 |
妇产科学 | 103篇 |
基础医学 | 1223篇 |
口腔科学 | 188篇 |
临床医学 | 622篇 |
内科学 | 1632篇 |
皮肤病学 | 216篇 |
神经病学 | 575篇 |
特种医学 | 410篇 |
外国民族医学 | 2篇 |
外科学 | 1200篇 |
综合类 | 66篇 |
一般理论 | 1篇 |
预防医学 | 481篇 |
眼科学 | 97篇 |
药学 | 379篇 |
中国医学 | 4篇 |
肿瘤学 | 330篇 |
出版年
2022年 | 47篇 |
2021年 | 116篇 |
2020年 | 63篇 |
2019年 | 84篇 |
2018年 | 116篇 |
2017年 | 80篇 |
2016年 | 138篇 |
2015年 | 142篇 |
2014年 | 169篇 |
2013年 | 237篇 |
2012年 | 318篇 |
2011年 | 370篇 |
2010年 | 171篇 |
2009年 | 186篇 |
2008年 | 314篇 |
2007年 | 363篇 |
2006年 | 336篇 |
2005年 | 279篇 |
2004年 | 282篇 |
2003年 | 313篇 |
2002年 | 273篇 |
2001年 | 239篇 |
2000年 | 271篇 |
1999年 | 217篇 |
1998年 | 81篇 |
1997年 | 85篇 |
1996年 | 57篇 |
1995年 | 55篇 |
1994年 | 54篇 |
1993年 | 47篇 |
1992年 | 124篇 |
1991年 | 122篇 |
1990年 | 108篇 |
1989年 | 111篇 |
1988年 | 120篇 |
1987年 | 139篇 |
1986年 | 118篇 |
1985年 | 113篇 |
1984年 | 87篇 |
1983年 | 68篇 |
1981年 | 46篇 |
1979年 | 75篇 |
1978年 | 64篇 |
1976年 | 46篇 |
1974年 | 61篇 |
1973年 | 74篇 |
1972年 | 53篇 |
1971年 | 52篇 |
1970年 | 49篇 |
1968年 | 51篇 |
排序方式: 共有7846条查询结果,搜索用时 0 毫秒
31.
The locations of extracorporeal shock wave treatment induced renal vascular injury and the sources of significant renal hemorrhage were determined in a rat model by means of two different vascular casting procedures. Silicone-rubber injected vascular preparations for light microscopy or corrosion casts for scanning electron microscopy were made following gross examination of the treated organs and their contralateral controls. After 1000 shock waves at 18 kV, five out of 20 treated kidneys appeared to be normal or minimally affected, while 15 showed gross evidence of marked vascular injury. Gross interstitial hemorrhage (15/20), subcapsular hematomas (7/20), and hemorrhages into the renal pelvis (5/20) were confirmed by extravasations of casting materials. These could be traced back to their vascular sources in several instances. Disruptions of interlobar and arcuate veins gave rise to most significant interstitial, subcapsular, and renal pelvic extravasations. On a microscopic scale cortical venules were among the most frequently injured vessels. The arterial vasculature was not spared. Arterial injury ranged from complete arcuate occlusion to small afferent arteriolar and glomerular capillary extravasations. The significance of shock wave induced vascular injury is discussed with respect to potential clinical side effects of ESWL. 相似文献
32.
33.
PURPOSE: To compare scleral Tono-Pen (Medtronic Solan, Jacksonville, FL) readings to corneal Tono-Pen readings. METHODS: Intraocular pressure (IOP) was measured prospectively in 72 eyes of 37 adult patients and in 10 eyes of 5 children. Measurements were taken on the central cornea and on the sclera. Recorded measurements were within 5% confidence levels by Tono-Pen. RESULTS: Corneal IOP ranged from 10 to 28 mm Hg (mean +/- standard deviation, 17.0 +/- 3.8 mm Hg). Scleral measurements ranged from 4 to 99 mm Hg (40.4 +/- 23.0 mm Hg). Scleral measurements ranged from 11 mm Hg lower to 76 mm Hg higher than corneal measurements. CONCLUSIONS: Tono-Pen readings obtained from sclera are of no clinical value and should not be used to approximate corneal IOP. 相似文献
34.
N Auza J P Braun P Benard J P Thouvenot A G Rico 《Veterinary and human toxicology》1989,31(6):535-537
Two groups of 4 sheep received a daily iv injection of sodium heptamolybdate (100mg/day) or of saline for 2 weeks to study the hematological and plasma biochemical effects of molybdenum toxicosis. In molybdenum-dosed sheep, there was hypercupremia, mild anemia due to the decrease of copper concentration in the liver and moderate hepatocellular damage probably due to a direct toxic effect of molybdenum against the liver. 相似文献
35.
36.
MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献
37.
M Braun F Boman J M Hascoet P Chastagner A Brunet C Simon 《Journal of neuroradiology. Journal de neuroradiologie》1992,19(1):68-74
The authors report two cases of brain tissue heterotopia in the nasopharynx, without other malformations and, in one of the cases, with a persistent craniopharyngeal canal opening onto the heterotopia. This exceptional malformation is very similar to brain heterotopia in the nose, or "nasal glioma", which is more frequent and less diversified at histology. The malformation is revealed by obstruction of the pharynx with respiratory distress immediately after birth or during the first weeks of life. Total surgical excision provides cure without sequelae. The diagnosis is based on histology. MRI is essential to the diagnostic and pretherapeutic evaluation, notably to avoid missing an ectopic hypophysis, but it is insufficient to diagnose a sphenoidal meningoencephalocele. 相似文献
38.
Verapamil (V) is a specific inhibitor of the P-glycoprotein (mdr1) in the hepatocyte canalicular membrane. Cyclosporin A (CsA) as an essential immunosuppressive drug has potentially cholestatic adverse effects on the liver, but increases the expression of mdr1. In precision-cut liver slices from 34- to 40-day-old male Wistar rats 26 individual free and conjugated bile acids (BAs) as markers of hepatic transport and synthesis function were analysed after 4 h incubation with V (100 microM) or CsA (5 microM) in Krebs-Henseleit buffer. Some slices were loaded with cholic acid (CA 5 microM) or tauro-ursodeoxycholic acid (T-UDCA 5 microM) to investigate the V and CsA effects under conditions of BA supplementation. BAs were determined in tissue and medium by HPLC with postcolumn derivatisation and fluorescence detection. V and CsA, influencing different targets in BA transport, enhanced slice concentrations of T- and glyco- (G-) conjugated CA only when exogenous CA was given additionally. This BA accumulation in tissue is more reflected at decreased medium concentrations of these BAs after V and CsA incubations. Both V and CsA also inhibited CA uptake into the slices. The acidic chenodeoxycholic acid (CDCA) synthesis pathway is disturbed: T- and G-CDCA concentrations are diminished in slices and medium after V and CsA incubations. T-UDCA plus V or CsA enhanced not only its own slice concentration but also the concentration of the trihydroxylated tauro-muricholic acid (T-beta-MCA), reflecting the conversion of the accumulated dihydroxylated T-UDCA into the T-beta-MCA. The similar effects of V and CsA on BA transport and metabolism can be explained by mdr1 mediated disturbances of cellular ATP transport rather than by inhibition of individual BA transporters. 相似文献
39.
Krücken J Dkhil MA Braun JV Schroetel RM El-Khadragy M Carmeliet P Mossmann H Wunderlich F 《Infection and immunity》2005,73(1):436-443
Testosterone induces a lethal outcome in otherwise self-healing blood-stage malaria caused by Plasmodium chabaudi. Here, we examine possible testosterone effects on the antimalaria effectors spleen and liver in female C57BL/6 mice. Self-healing malaria activates gating mechanisms in the spleen and liver that lead to a dramatic reduction in trapping activity, as measured by quantifying the uptake of 3-mum-diameter fluorescent polystyrol particles. However, testosterone delays malaria-induced closing of the liver, but not the spleen. Coincidently, testosterone causes an approximately 3- to 28-fold depression of the mRNA levels of nine malaria-responsive genes, out of 299 genes tested, only in the liver and not in the spleen, as shown by cDNA arrays and Northern blotting. Among these are the genes encoding plasminogen activator inhibitor (PAI1) and hydroxysteroid sulfotransferase (STA2). STA2, which detoxifies bile acids, is suppressed 10-fold by malaria and an additional 28-fold by testosterone, suggesting a severe perturbation of bile acid metabolism. PAI1 is protective against malaria, since disruption of the PAI1 gene results in partial loss of the ability to control the course of P. chabaudi infections. Collectively, our data indicate that the liver rather than the spleen is a major target organ for testosterone-mediated suppression of resistance against blood-stage malaria. 相似文献
40.
Identification of a novel mycobacterial histone H1 homologue (HupB) as an antigenic target of pANCA monoclonal antibody and serum immunoglobulin A from patients with Crohn's disease
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Cohavy O Harth G Horwitz M Eggena M Landers C Sutton C Targan SR Braun J 《Infection and immunity》1999,67(12):6510-6517
pANCA is a marker antibody associated with inflammatory bowel disease (IBD), including most patients with ulcerative colitis and a subset with Crohn's disease. This study addressed the hypothesis that pANCA reacts with an antigen(s) of microbial agents potentially relevant to IBD pathogenesis. Using a pANCA monoclonal antibody, we have previously identified the C-terminal basic random-coil domain of histone H1 as a pANCA autoantigen. BLAST analysis of the peptide databases revealed H1 epitope homologues in open reading frames of the Mycobacterium tuberculosis genome. Western analysis of extracts from six mycobacterial species directly demonstrated reactivity to a single, conserved approximately 32-kDa protein. Direct protein sequencing, followed by gene cloning, revealed a novel 214-amino-acid protein, an iron-regulated protein recently termed HupB. Sequence analysis demonstrated its homology with the mammalian histone H1 gene family, and recombinant protein expression confirmed its reactivity with the 5-3 pANCA monoclonal antibody. Binding activity of patient serum immunoglobulin G (IgG) to HupB did not correlate with reactivity to histone H1 or pANCA, indicating the complex character of the pANCA antigen. However, anti-HupB IgA was strongly associated with Crohn's disease (P < 0.001). These findings indicate that the 5-3 pANCA monoclonal antibody detects a structural domain recurrent among mycobacteria and cross-reactive with a DNA-binding domain of histone H1. The association of HupB-binding serum IgA with IBD provides new evidence for the association of a mycobacterial species with Crohn's disease. 相似文献