全文获取类型
收费全文 | 4694篇 |
免费 | 304篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 150篇 |
妇产科学 | 100篇 |
基础医学 | 833篇 |
口腔科学 | 146篇 |
临床医学 | 452篇 |
内科学 | 820篇 |
皮肤病学 | 93篇 |
神经病学 | 655篇 |
特种医学 | 122篇 |
外科学 | 404篇 |
综合类 | 26篇 |
一般理论 | 2篇 |
预防医学 | 315篇 |
眼科学 | 180篇 |
药学 | 284篇 |
中国医学 | 23篇 |
肿瘤学 | 341篇 |
出版年
2024年 | 4篇 |
2023年 | 41篇 |
2022年 | 53篇 |
2021年 | 80篇 |
2020年 | 76篇 |
2019年 | 104篇 |
2018年 | 95篇 |
2017年 | 121篇 |
2016年 | 121篇 |
2015年 | 135篇 |
2014年 | 142篇 |
2013年 | 231篇 |
2012年 | 387篇 |
2011年 | 355篇 |
2010年 | 213篇 |
2009年 | 208篇 |
2008年 | 323篇 |
2007年 | 361篇 |
2006年 | 324篇 |
2005年 | 296篇 |
2004年 | 308篇 |
2003年 | 273篇 |
2002年 | 259篇 |
2001年 | 46篇 |
2000年 | 28篇 |
1999年 | 60篇 |
1998年 | 64篇 |
1997年 | 61篇 |
1996年 | 42篇 |
1995年 | 22篇 |
1994年 | 21篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 18篇 |
1990年 | 9篇 |
1989年 | 13篇 |
1988年 | 7篇 |
1987年 | 10篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 8篇 |
1983年 | 7篇 |
1982年 | 5篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1978年 | 9篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1974年 | 3篇 |
1961年 | 2篇 |
排序方式: 共有5024条查询结果,搜索用时 15 毫秒
41.
Denecke C Reutzel-Selke A Sawitzki B Boenisch O Khalpey Z Seifert M Pratschke J Volk HD Tullius SG 《Transplant immunology》2012,26(4):176-185
Tolerance induction protocols have been successfully tested in animal models, yet their compatibility with immunosuppressive drugs remains to be fully elucidated. Our own previous data have indicated that cyclosporine A (CsA) affects the balance of effector and regulatory mechanisms with low-dose CsA doses promoting hyporesponsiveness. Here, we present a fully mismatched rat kidney model in which low-dose CsA treatment induces donor hyporesponsiveness to secondary renal allografts. Lewis recipients of DA kidney grafts received low, medium or high doses of CsA × 10 days. By 30 days, the primary transplant was removed and a second transplant of donor origin was engrafted. Following low-dose CsA, but not high-dose CsA treatment of the primary recipient, secondary transplants were accepted long-term in the absence of immunosuppression. Regulatory T-cell function was unimpaired and independent of the CyA dosage. Of note, low-dose CsA significantly reduced alloantibody titers in primary recipients. Adoptive transfer of graft infiltrating cells or splenocytes from hyporesponsive recipients supported long-term acceptance of donor kidney allografts. These results demonstrate a dose-dependent and transferable "pro-tolerogenic" effect of low-dose CsA treatment. This model is of clinical relevance to test the interference of CsA with tolerance induction in the absence of additional immunosuppression. 相似文献
42.
Two studies of assault survivors (Ns = 180, 70) examined associations between posttraumatic growth (PTG) and posttrauma psychopathology. Both studies found significant curvilinear associations between PTG and posttraumatic stress disorder, whereas only Study 1 found a curvilinear association between PTG and depression symptom severity. Survivors with no or high growth levels reported fewer symptoms than those who reported moderate growth. Study 1 also investigated potential PTG predictors. Non‐Caucasian ethnicity, religiousness, peritraumatic fear, shame, and ruminative thinking style, assessed at 2 weeks, predicted growth at 6 months. Posttraumatic growth may thus be most relevant in trauma survivors who attach enduring significance to the trauma for their lives and show initial distress. Moderate levels of PTG do not seem to ameliorate posttrauma psychopathology. 相似文献
43.
Frederike C. Ling Arnulf H. Hoelscher Daniel Vallböhmer Daniel Schmidt Susanne Picker Birgit S. Gathof Elfriede Bollschweiler Paul M. Schneider 《Journal of gastrointestinal surgery》2009,13(4):581-586
Background Perioperative transfusion of allogeneic blood has been hypothesized to have an immunomodulatory effect and influence survival
in several cancer types. This study evaluates the association between receipt of leucocyte-depleted and non-depleted allogeneic
blood and survival following esophagectomy for cancer.
Methods A retrospective analysis was performed including 291 patients with esophageal cancers who underwent transthoracic en bloc
esophagectomy and extended mediastinal lymphadenectomy. Neoadjuvant chemoradiation was administered in 152 (52.2%) patients.
Perioperative blood transfusions were quantified and the potential prognostic cutoff for transfused units was calculated according
to LeBlanc.
Results The median number of perioperative blood transfusions was 2 (0–24), and 106 patients (36.4%) received no transfusions. Patients
with one or less blood transfusion showed a significantly improved survival compared to patients receiving more than one unit
(p < 0.009). In multivariate analysis, blood transfusion categories showed significance (p < 0.015) next to pT, pN, pM category, and residual tumor categories (R-categories). Separate analysis of 183 patients treated
after the mandatory introduction of leukocyte-depleted blood transfusions detected a strong tendency, but no significant difference
in survival for patients getting one or less or more than one transfusion (p = 0.056). Receipt of leukocyte-depleted versus non-depleted units, however, had no influence on survival (p = 0.766).
Conclusions The need for perioperative allogeneic blood transfusions is significantly associated with poorer survival following resection
for esophageal cancer by univariate and multivariate analysis. Our data suggest that the reduction of leukocytes in allogeneic
transfusions is not sufficient to overcome the negative influence on survival.
This paper was presented at DDW 2008 in the San Diego Convention Center, San Diego, CA, May 17–22, 2008. 相似文献
44.
Hamoir M Shah JP Desuter G Grégoire V Ledeghen S Plouin-Gaudon I Rombaux P Weynand B Lengelé B 《Head & neck》2005,27(11):963-9; discussion 969
BACKGROUND: We assessed the prevalence of histologically proven normal or invaded lymph nodes in the apex of level V. METHODS: Seventy neck dissections were performed in 41 patients with mucosal head and neck squamous cell carcinoma (SCC). Fifty-one neck dissections were performed in 30 previously untreated patients (group 1); 19 neck dissections were carried out in 11 patients previously irradiated (group 2). RESULTS: Pathologic analysis was unable to identify any lymph node in 70% of the apex specimens. In group 1, no lymph nodes were detected in 63%, whereas one or more noninvaded lymph nodes were present in 37%; in group 2, no lymph nodes were identified in 89%, whereas one or more normal lymph nodes were found in 11% (p = .03). Metastatic lymph nodes were never identified. CONCLUSIONS: The prevalence of lymph nodes in the apex was 30%. No invaded lymph nodes were identified. In addition to anatomic evidence, these results suggest that dissection of the apex is not necessary in mucosal head and neck SCC. 相似文献
45.
46.
The PCBP1 gene encoding poly(rc) binding protein i is recurrently mutated in Burkitt lymphoma 下载免费PDF全文
Rabea Wagener Sietse M. Aukema Matthias Schlesner Andrea Haake Birgit Burkhardt Alexander Claviez Hans G. Drexler Michael Hummel Markus Kreuz Markus Loeffler Maciej Rosolowski Cristina Lpez Peter Mller Julia Richter Marius Rohde Matthew J. Betts Robert B. Russell Stephan H. Bernhart Steve Hoffmann Philip Rosenstiel Markus Schilhabel Monika Szczepanowski Lorenz Trümper Wolfram Klapper Reiner Siebert 《Genes, chromosomes & cancer》2015,54(9):555-564
The genetic hallmark of Burkitt lymphoma is the translocation t(8;14)(q24;q32), or one of its light chain variants, resulting in IG‐MYC juxtaposition. However, these translocations alone are insufficient to drive lymphomagenesis, which requires additional genetic changes for malignant transformation. Recent studies of Burkitt lymphoma using next generation sequencing approaches have identified various recurrently mutated genes including ID3, TCF3, CCND3, and TP53. Here, by using similar approaches, we show that PCBP1 is a recurrently mutated gene in Burkitt lymphoma. By whole‐genome sequencing, we identified somatic mutations in PCBP1 in 3/17 (18%) Burkitt lymphomas. We confirmed the recurrence of PCBP1 mutations by Sanger sequencing in an independent validation cohort, finding mutations in 3/28 (11%) Burkitt lymphomas and in 6/16 (38%) Burkitt lymphoma cell lines. PCBP1 is an intron‐less gene encoding the 356 amino acid poly(rC) binding protein 1, which contains three K‐Homology (KH) domains and two nuclear localization signals. The mutations predominantly (10/12, 83%) affect the KH III domain, either by complete domain loss or amino acid changes. Thus, these changes are predicted to alter the various functions of PCBP1, including nuclear trafficking and pre‐mRNA splicing. Remarkably, all six primary Burkitt lymphomas with a PCBP1 mutation expressed MUM1/IRF4, which is otherwise detected in around 20–40% of Burkitt lymphomas. We conclude that PCBP1 mutations are recurrent in Burkitt lymphomas and might contribute, in cooperation with other mutations, to its pathogenesis. © 2015 Wiley Periodicals, Inc. 相似文献
47.
Brock A. Peters Bahram G. Kermani Oleg Alferov Misha R. Agarwal Mark A. McElwain Natali Gulbahce Daniel M. Hayden Y. Tom Tang Rebecca Yu Zhang Rick Tearle Birgit Crain Renata Prates Alan Berkeley Santiago Munné Radoje Drmanac 《Genome research》2015,25(3):426-434
Currently, the methods available for preimplantation genetic diagnosis (PGD) of in vitro fertilized (IVF) embryos do not detect de novo single-nucleotide and short indel mutations, which have been shown to cause a large fraction of genetic diseases. Detection of all these types of mutations requires whole-genome sequencing (WGS). In this study, advanced massively parallel WGS was performed on three 5- to 10-cell biopsies from two blastocyst-stage embryos. Both parents and paternal grandparents were also analyzed to allow for accurate measurements of false-positive and false-negative error rates. Overall, >95% of each genome was called. In the embryos, experimentally derived haplotypes and barcoded read data were used to detect and phase up to 82% of de novo single base mutations with a false-positive rate of about one error per Gb, resulting in fewer than 10 such errors per embryo. This represents a ∼100-fold lower error rate than previously published from 10 cells, and it is the first demonstration that advanced WGS can be used to accurately identify these de novo mutations in spite of the thousands of false-positive errors introduced by the extensive DNA amplification required for deep sequencing. Using haplotype information, we also demonstrate how small de novo deletions could be detected. These results suggest that phased WGS using barcoded DNA could be used in the future as part of the PGD process to maximize comprehensiveness in detecting disease-causing mutations and to reduce the incidence of genetic diseases.Worldwide, more than 5 million babies (Ferraretti et al. 2013) have been born through in vitro fertilization (IVF) since the birth of the first in 1978 (Steptoe and Edwards 1978). Exact numbers are difficult to determine, but it has been estimated that currently 350,000 babies are born yearly through IVF (de Mouzon et al. 2009, 2012; Centers for Disease Control and Prevention 2011; Ferraretti et al. 2013). That number is expected to rise, as advanced maternal age is associated with decreased fertility rates and women in developed countries continue to delay childbirth to later ages. In 95% of IVF procedures, no diagnostic testing of the embryos is performed (https://www.sartcorsonline.com/rptCSR_PublicMultYear.aspx?ClinicPKID=0). Couples with prior difficulties conceiving or those wishing to avoid the transmission of highly penetrant heritable diseases often choose to perform preimplantation genetic diagnosis (PGD). PGD involves the biopsy of one cell from a 3-d embryo or the recently more preferred method, due to improved implantation success rates (Scott et al. 2013b), of up to 10 cells from a 5- to 6-d blastocyst-stage embryo. Following biopsy, genetic analysis is performed on the isolated cell(s). Currently this is an assay for translocations and the correct chromosome copy number (Hodes-Wertz et al. 2012; Munne 2012; Yang et al. 2012; Scott et al. 2013a; Yin et al. 2013), a unique test designed and validated for each specific heritable disease (Gutierrez-Mateo et al. 2009), or a combination of both (Treff et al. 2013). Importantly, none of these approaches can detect de novo mutations.Advanced maternal age has long been associated with an increased risk of producing aneuploid embryos (Munne et al. 1995; Crow 2000; Hassold and Hunt 2009) and giving birth to a child afflicted with Down syndrome or other diseases resulting from chromosomal copy number alterations. Conversely, children of older fathers have been shown to have an increase in single base and short multibase insertion/deletion (indels) de novo mutations (Kong et al. 2012). Many recent large-scale sequencing studies have found that de novo variations spread across many different genes are likely to be the cause of a large fraction of autism cases (Michaelson et al. 2012; O’Roak et al. 2012; Sanders et al. 2012; De Rubeis et al. 2014; Iossifov et al. 2014), severe intellectual disability (Gilissen et al. 2014), epileptic encephalopathies (Epi4K Consortium and Epilepsy Phenome/Genome Project 2013), and many other congenital disorders (de Ligt et al. 2012; Veltman and Brunner 2012; Yang et al. 2013; Al Turki et al. 2014). Additionally rare and de novo variations have been suggested to be prevalent in patients with schizophrenia (Fromer et al. 2014; Purcell et al. 2014), and Michaelson et al. (2012) found that single base de novo mutations affect conserved regions of the genome and essential genes more often than regions of unknown function. Current targeted approaches to PGD would miss many of these important functional changes within the embryonic DNA sequence, and even a whole-genome sequencing (WGS)–based carrier screen of both parents would not enable comprehensive preimplantation or prenatal diagnoses due to de novo mutations. As more parents delay childbirth into their mid-30s and later, these studies suggest we should try to provide better diagnostic tests for improving the health of newborns. In this study, we demonstrate the use of an advanced WGS process that provides an accurate and phased genome sequence from about 10 cells, allowing highly sensitive and specific detection of single base de novo mutations from IVF blastocyst biopsies. 相似文献
48.
49.
50.