全文获取类型
收费全文 | 1484篇 |
免费 | 122篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 65篇 |
儿科学 | 53篇 |
妇产科学 | 21篇 |
基础医学 | 217篇 |
口腔科学 | 10篇 |
临床医学 | 150篇 |
内科学 | 312篇 |
皮肤病学 | 120篇 |
神经病学 | 150篇 |
特种医学 | 20篇 |
外科学 | 96篇 |
综合类 | 9篇 |
一般理论 | 1篇 |
预防医学 | 142篇 |
眼科学 | 15篇 |
药学 | 99篇 |
肿瘤学 | 129篇 |
出版年
2023年 | 9篇 |
2022年 | 10篇 |
2021年 | 20篇 |
2020年 | 20篇 |
2019年 | 35篇 |
2018年 | 33篇 |
2017年 | 33篇 |
2016年 | 41篇 |
2015年 | 37篇 |
2014年 | 57篇 |
2013年 | 97篇 |
2012年 | 122篇 |
2011年 | 108篇 |
2010年 | 64篇 |
2009年 | 39篇 |
2008年 | 92篇 |
2007年 | 105篇 |
2006年 | 91篇 |
2005年 | 110篇 |
2004年 | 87篇 |
2003年 | 86篇 |
2002年 | 66篇 |
2001年 | 10篇 |
2000年 | 14篇 |
1999年 | 13篇 |
1998年 | 18篇 |
1997年 | 14篇 |
1996年 | 10篇 |
1995年 | 10篇 |
1994年 | 10篇 |
1993年 | 14篇 |
1992年 | 7篇 |
1991年 | 10篇 |
1990年 | 7篇 |
1989年 | 5篇 |
1988年 | 12篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 11篇 |
1981年 | 7篇 |
1980年 | 14篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1964年 | 5篇 |
排序方式: 共有1609条查询结果,搜索用时 490 毫秒
21.
22.
Increased HLA A1 and diminished HLA A3 in lymphocytic colitis compared to controls and patients with collagenous colitis 总被引:3,自引:0,他引:3
Dr. Francis M. Giardiello MD Audrey J. Lazenby MD John H. Yardley MD Wilma B. Bias PhD James Johnson MD Robert G. Alianiello BS Marshall S. Bedine MD Theodore M. Bayless MD 《Digestive diseases and sciences》1992,37(4):496-499
Lymphocytic colitis is a newly described chronic diarrheal disorder. Although its etiology is unknown, the possibility has been raised that autoimmunity may play a role in both lymphocytic and collagenous colitis, a similar clinicopathologic illness. The frequencies of HLA class I and class II antigens were examined in 24 white patients with lymphocytic colitis and in 47 white patients with collagenous colitis. Frequencies in these two disorders were compared to control white populations and to each other. An increased frequency of HLA-A1 was noted in 16 of 24 lymphocytic colitis patients (66.6%) compared with 1089 of 3942 controls (27.6%) (P<0.005; relative risk 5.2). Furthermore, HLA-A3 was found in decreased frequency in lymphocytic colitis patients: 0 of 24 (0%) compared with 1017 of 3942 controls (25.8%) (P<0.05; relative risk 0.0). Collagenous colitis patients had no significant deviation from control frequencies of HLA antigens. In lymphocytic colitis, there was no significant increase in B8 or DR3 antigens, which are found in linkage disequilibrium with A1 and associated with many autoimmune diseases. Moreover, the frequency of autoimmune-associated class I HLA antigens was not increased in lymphocytic colitis. Statistically significant differences existed between lymphocytic and collagenous colitis in HLA-A1, A3, Bw6, and B7 antigen frequencies. The HLA patterns noted previously in other gastrointestinal disorders, including ulcerative colitis and Crohn's disease, were not apparent in lymphocytic or collagenous colitis. HLA typing provides further evidence that lymphocytic colitis is a distinct form of chronic intestinal inflammatory disease associated with HLA class I phenotypes.Presented in part at the American Gastroenterological Association in May 1988 and published with preliminary data in a previous article (reference 1).Supported in part by The National Foundation for Ileitis and Colitis, by an institutional grant from The Johns Hopkins School of Medicine, and by outpatient GCRC grant RR00722. 相似文献
23.
24.
The Systematic Tool to Reduce Inappropriate Prescribing (STRIP): Combining implicit and explicit prescribing tools to improve appropriate prescribing
下载免费PDF全文
![点击此处可从《Journal of evaluation in clinical practice》网站下载免费的PDF全文](/ch/ext_images/free.gif)
25.
26.
Wilma Koutstaal Daniel L. Schacter Mieke Verfaellie Carolyn Brenner Eric M. Jackson 《Cognitive neuropsychology》2013,30(3-5):317-341
Previous research suggests that amnesics may show impaired semantically based false recognition under conditions where control participants show high levels of gist-based errors, but little or no impairment when controls show less robust false recognition. Using abstract novel objects, we examined perceptually based false recognition in amnesics under conditions designed to induce differing levels of false recognition in controls. Whereas amnesics showed significantly impaired false recognition for category prototypes, and numerically impaired false recognition when many perceptually similar exemplars were studied-conditions where controls showed high rates of illusory recognition-amnesics and controls showed lower, and comparable, levels of false recognition when few related exemplars were studied, or lures were at a far transformational distance from the prototype. Although amnesics may be able to extract some information regarding the perceptual “gist” of studied items, they appear to do so less efficiently than controls. 相似文献
27.
J. Brauner M. Hallin A. Deplano R. De Mendonça C. Nonhoff R. De Ryck S. Roisin M. J. Struelens O. Denis 《European journal of clinical microbiology & infectious diseases》2013,32(5):613-620
The present study reports the evolution of the demographic characteristics and the molecular epidemiology of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) in Belgium from 2005 to 2009. Four hundred and ten CA-MRSA isolates were prospectively collected and screened for the presence of Panton–Valentin leucocidin (PVL) and toxic shock syndrome toxin 1 (TSST-1) encoding genes, while clinical information were recorded. PVL- and TSST-1-positive isolates were genotyped by pulsed-field gel electrophoresis (PFGE). Staphylococcal cassette chromosome mec (SCCmec) type, spa type and multilocus sequence type (MLST) were determined on representative isolates. One hundred and fifty-nine (39 %) isolates were PVL-positive. PVL-positive isolates were significantly more frequently isolated from skin or soft tissue than PVL-negative isolates, causing mainly subcutaneous abscesses and furuncles. Patients with PVL-positive CA-MRSA were significantly younger than patients with PVL-negative CA-MRSA. Eighty-seven percent of the PVL-positive isolates belonged to a limited number (n?=?7) of PFGE types belonging to sequence types (ST) ST80, ST8, ST30, ST5, ST152, ST338 and a new ST, a single-locus variant of ST1. A temporal evolution of the distribution of these PFGE types was observed, characterised by (1) the dissemination of the ST8-SCCmecIV arcA-positive (USA300) genotype and (2) a genetic diversification. Forty-seven (11 %) strains were TSST-1-positive, of which 65 % clustered into four PFGE types, all belonging to ST5. The epidemiology of CA-MRSA in Belgium is changing, as the rapid diffusion of the USA300 clone seems to occur, together with a clonal diversification. 相似文献
28.
Carla Blits‐Huizinga John G.J.M. Bol Annemieke J. Rozemuller Piet V.J.M. Hoogland Paul J. Lucassen Benjamin Drukarch Wilma D.J. van de Berg Anne‐Marie van Dam 《Brain pathology (Zurich, Switzerland)》2014,24(2):152-165
The olfactory bulb (OB) is affected early in both Parkinson's (PD) and Alzheimer's disease (AD), evidenced by the presence of disease‐specific protein aggregates and an early loss of olfaction. Whereas previous studies showed amoeboid microglia in the classically affected brain regions of PD and AD patients, little was known about such changes in the OB. Using a morphometric approach, a significant increase in amoeboid microglia density within the anterior olfactory nucleus (AON) of AD and PD patients was observed. These amoeboid microglia cells were in close apposition to β‐amyloid, hyperphosphorylated tau or α‐synuclein deposits, but no uptake of pathological proteins by microglia could be visualized. Subsequent analysis showed (i) no correlation between microglia and α‐synuclein (PD), (ii) a positive correlation with β‐amyloid (AD), and (iii) a negative correlation with hyperphosphorylated tau (AD). Furthermore, despite the observed pathological alterations in neurite morphology, neuronal loss was not apparent in the AON of both patient groups. Thus, we hypothesize that, in contrast to the classically affected brain regions of AD and PD patients, within the AON rather than neuronal loss, the increased density in amoeboid microglial cells, possibly in combination with neurite pathology, may contribute to functional deficits. 相似文献
29.
Hermine A van Duyvenvoorde Julian C Lui Sarina G Kant Wilma Oostdijk Antoinet CJ Gijsbers Mari?tte JV Hoffer Marcel Karperien Marie JE Walenkamp Cees Noordam Paul G Voorhoeve Verónica Mericq Alberto M Pereira Hedi L Claahsen-van de Grinten Sandy A van Gool Martijn H Breuning Monique Losekoot Jeffrey Baron Claudia AL Ruivenkamp Jan M Wit 《European journal of human genetics : EJHG》2014,22(5):602-609
Height is a highly heritable and classic polygenic trait. Recent genome-wide association studies (GWAS) have revealed that at least 180 genetic variants influence adult height. However, these variants explain only about 10% of the phenotypic variation in height. Genetic analysis of short individuals can lead to the discovery of novel rare gene defects with a large effect on growth. In an effort to identify novel genes associated with short stature, genome-wide analysis for copy number variants (CNVs), using single-nucleotide polymorphism arrays, in 162 patients (149 families) with short stature was performed. Segregation analysis was performed if possible, and genes in CNVs were compared with information from GWAS, gene expression in rodents'' growth plates and published information. CNVs were detected in 40 families. In six families, a known cause of short stature was found (SHOX deletion or duplication, IGF1R deletion), in two combined with a de novo potentially pathogenic CNV. Thirty-three families had one or more potentially pathogenic CNVs (n=40). In 24 of these families, segregation analysis could be performed, identifying three de novo CNVs and nine CNVs segregating with short stature. Four were located near loci associated with height in GWAS (ADAMTS17, TULP4, PRKG2/BMP3 and PAPPA). Besides six CNVs known to be causative for short stature, 40 CNVs with possible pathogenicity were identified. Segregation studies and bioinformatics analysis suggested various potential candidate genes. 相似文献
30.