全文获取类型
收费全文 | 997篇 |
免费 | 62篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 17篇 |
妇产科学 | 6篇 |
基础医学 | 90篇 |
口腔科学 | 34篇 |
临床医学 | 73篇 |
内科学 | 278篇 |
皮肤病学 | 14篇 |
神经病学 | 51篇 |
特种医学 | 67篇 |
外科学 | 121篇 |
综合类 | 10篇 |
预防医学 | 84篇 |
眼科学 | 4篇 |
药学 | 125篇 |
1篇 | |
中国医学 | 1篇 |
肿瘤学 | 90篇 |
出版年
2022年 | 8篇 |
2021年 | 17篇 |
2020年 | 8篇 |
2019年 | 18篇 |
2018年 | 13篇 |
2017年 | 14篇 |
2016年 | 28篇 |
2015年 | 16篇 |
2014年 | 25篇 |
2013年 | 29篇 |
2012年 | 37篇 |
2011年 | 36篇 |
2010年 | 35篇 |
2009年 | 28篇 |
2008年 | 46篇 |
2007年 | 50篇 |
2006年 | 50篇 |
2005年 | 49篇 |
2004年 | 49篇 |
2003年 | 30篇 |
2002年 | 35篇 |
2001年 | 30篇 |
2000年 | 28篇 |
1999年 | 28篇 |
1998年 | 19篇 |
1997年 | 15篇 |
1996年 | 20篇 |
1995年 | 16篇 |
1994年 | 16篇 |
1993年 | 18篇 |
1992年 | 18篇 |
1991年 | 17篇 |
1990年 | 17篇 |
1989年 | 15篇 |
1988年 | 19篇 |
1987年 | 16篇 |
1986年 | 21篇 |
1985年 | 11篇 |
1984年 | 6篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1980年 | 9篇 |
1979年 | 7篇 |
1978年 | 11篇 |
1977年 | 9篇 |
1974年 | 7篇 |
1972年 | 5篇 |
1971年 | 6篇 |
1970年 | 5篇 |
1967年 | 8篇 |
排序方式: 共有1069条查询结果,搜索用时 15 毫秒
1.
Prevalence of H pylori associated 'high risk gastritis' for development of gastric cancer in patients with normal endoscopic findings 总被引:1,自引:0,他引:1
Andreas Leodolter Matthias P Ebert Ulrich Peitz Kathlen Wolle Stefan Kahl Peter Malfertheiner 《World journal of gastroenterology : WJG》2006,(34)
INTRODUCTION H pylori infection is an established risk factor for development of gastric cancer[1,2]. According to the model of carcinogenesis of the intestinal type adenocarcinoma proposed by Correa, the multi-step development starts from the condition o… 相似文献
2.
3.
4.
5.
Biochemical characterization of the protective membrane glycoprotein GP46/M-2 of Leishmania amazonensis. 总被引:3,自引:0,他引:3
Biochemical features of the immunologically protective, membrane glycoprotein GP46/M-2 of Leishmania amazonensis have been investigated. The protein appears to have a single carbohydrate side chain of approximately 3 kDa, representing 7% of the mass of the mature GP46/M-2 protein. Experiments removing this carbohydrate side chain from GP46/M-2 indicate that the carbohydrate is not involved in the epitope recognized by the monoclonal antibody, M-2. As this monoclonal antibody recognizes a species-specific epitope, these data suggest that this determinant is defined by the polypeptide portion of the molecule. Studies employing the VSG-lipase as well as anti-CRD antibody clearly indicate that the molecule is anchored to the surface membrane of the promastigote via a phosphatidylinositol-linked lipid anchor. Neither the carbohydrate side chain nor the lipid anchor appear to be responsible for the apparent refractoriness of this protein to protease digestion, suggesting that properties of the polypeptide itself may be responsible. These data are discussed in terms of recent DNA-derived protein sequence of the GP46/M-2. 相似文献
6.
7.
8.
Development of flow cytogenetics and physical genome mapping in chickpea (Cicer arietinum L.) 总被引:2,自引:0,他引:2
K. Vláčilová D. Ohri J. Vrána J. Číhalíková M. Kubaláková G. Kahl J. Doležel 《Chromosome research》2002,10(8):695-706
Procedures for flow cytometric analysis and sorting of mitotic chromosomes (flow cytogenetics) have been developed for chickpea (Cicer arietinum). Suspensions of intact chromosomes were prepared from root tips treated to achieve a high degree of metaphase synchrony. The optimal protocol consisted of a treatment of roots with 2mmol/L hydroxyurea for 18h, a 4.5-h recovery in hydroxyurea-free medium, 2h incubation with 10µmol/L oryzalin, and ice-water treatment overnight. This procedure resulted in an average metaphase index of 47%. Synchronized root tips were fixed in 2% formaldehyde for 20min, and chromosome suspensions prepared by mechanical homogenization of fixed root tips. More than 4×105 morphologically intact chromosomes could be isolated from 15 root tips. Flow cytometric analysis of DAPI-stained chromosomes resulted in histograms of relative fluorescence intensity (flow karyotypes) containing eight peaks, representing individual chromosomes and/or groups of chromosomes with a similar relative DNA content. Five peaks could be assigned to individual chromosomes (A, B, C, G, H). The purity of sorted chromosome fractions was high, and chromosomes B and H could be sorted with 100% purity. PCR on flow-sorted chromosome fractions with primers for sequence-tagged microsatellite site (STMS) markers permitted assignment of the genetic linkage group LG8 to the smallest chickpea chromosome H. This study extends the number of legume species for which flow cytogenetics is available, and demonstrates the potential of flow cytogenetics for genome mapping in chickpea. 相似文献
9.
Evaluation of two chromogenic agar media for recovery and identification of Staphylococcus aureus small-colony variants
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Kipp F Kahl BC Becker K Baron EJ Proctor RA Peters G von Eiff C 《Journal of clinical microbiology》2005,43(4):1956-1959
To identify the most rapid and reliable technique for recovery and identification of Staphylococcus aureus small-colony variants (SCVs), the colonial appearance of 106 isolates representing SCVs and the normal phenotype were evaluated on two newly described chromogenic agar media. Although almost all of the SCVs grew on the chromogenic agar media, they did not exhibit a change of color. In comparison with conventional media, S. aureus ID agar (SAID; bioMerieux, La Balme Les Grottes, France) showed the most reliable results, with 49 of 53 SCVs tested growing either as an SCV colony or with a normal phenotype after only 24 h of incubation. Growth of SCVs was often not detected before 72 h of incubation on some of the media tested. In conclusion, the most accurate and rapid method to detect both the species S. aureus and the SCV phenotype is to inoculate specimens onto both Columbia blood agar and SAID. 相似文献
10.
Kurt Weising Dieter Kaemmer Jörg T. Epplen Franz Weigand Mohan Saxena Günter Kahl 《Current genetics》1991,19(6):483-489
Summary The ascomycete fungus Ascochyta rabiei, an important pathogen of the grain legume crop chickpea (Cicer arietinum L.) in the Mediterranean region, has not been adequately characterized in molecular terms. We therefore used DNA fingerprinting, with synthetic oligodeoxynucleotides complementary to simple repetitive sequences, to pathotype different isolates of the fungus. Six single-spored A. rabiei isolates were first categorized using a host differential set of nine chickpea genotypes. Seedlings were inoculated under controlled environmental conditions, and disease severity was recorded 9 days after inoculation. DNA was extracted from in vitro-grown mycelia of the six purified fungal isolates, restricted with EcoRI, HinfI, MboII and TaqI, and fingerprinted with radiolabeled (GATA)4, (GTG)5, (CA)8, and (TCC)5, respectively. High levels of polymorphism were detected with optimal enzyme/probe combinations that allow one to discriminate between the isolates. The potential of DNA fingerprinting with simple repetitive sequences can thus be expanded to the identification of fungal races and pathotypes. The characterization of the geographic distribution and genetic variability of pathotypes will facilitate the selection of suitable host cultivars to be grown in specific regions. 相似文献