全文获取类型
收费全文 | 1863篇 |
免费 | 84篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 47篇 |
妇产科学 | 47篇 |
基础医学 | 320篇 |
口腔科学 | 26篇 |
临床医学 | 186篇 |
内科学 | 317篇 |
皮肤病学 | 20篇 |
神经病学 | 218篇 |
特种医学 | 46篇 |
外科学 | 230篇 |
综合类 | 15篇 |
一般理论 | 1篇 |
预防医学 | 192篇 |
眼科学 | 33篇 |
药学 | 163篇 |
中国医学 | 4篇 |
肿瘤学 | 90篇 |
出版年
2023年 | 8篇 |
2022年 | 47篇 |
2021年 | 45篇 |
2020年 | 37篇 |
2019年 | 43篇 |
2018年 | 54篇 |
2017年 | 24篇 |
2016年 | 36篇 |
2015年 | 38篇 |
2014年 | 57篇 |
2013年 | 82篇 |
2012年 | 159篇 |
2011年 | 151篇 |
2010年 | 65篇 |
2009年 | 62篇 |
2008年 | 119篇 |
2007年 | 104篇 |
2006年 | 94篇 |
2005年 | 82篇 |
2004年 | 63篇 |
2003年 | 61篇 |
2002年 | 56篇 |
2001年 | 32篇 |
2000年 | 25篇 |
1999年 | 19篇 |
1998年 | 14篇 |
1997年 | 10篇 |
1995年 | 13篇 |
1994年 | 20篇 |
1992年 | 20篇 |
1990年 | 9篇 |
1989年 | 15篇 |
1988年 | 18篇 |
1987年 | 22篇 |
1986年 | 13篇 |
1985年 | 23篇 |
1984年 | 16篇 |
1983年 | 15篇 |
1981年 | 11篇 |
1979年 | 11篇 |
1978年 | 11篇 |
1976年 | 8篇 |
1974年 | 18篇 |
1973年 | 7篇 |
1972年 | 14篇 |
1971年 | 16篇 |
1970年 | 8篇 |
1969年 | 10篇 |
1968年 | 9篇 |
1965年 | 10篇 |
排序方式: 共有1965条查询结果,搜索用时 15 毫秒
61.
Judith L. Thijs Ian Strickland Carla A.F.M. Bruijnzeel-Koomen Stefan Nierkens Barbara Giovannone Edward F. Knol Eszter Csomor Bret R. Sellman Tomas Mustelin Matthew A. Sleeman Marjolein S. de Bruin-Weller Athula Herath Julia Drylewicz Richard D. May DirkJan Hijnen 《The Journal of allergy and clinical immunology》2018,141(4):1523-1526
62.
Comparison of pre‐ and post‐transplant sun‐safe behavior of kidney transplant recipients: What is needed to improve? 下载免费PDF全文
63.
Objectives To assess the safety of a cardiac rehabilitation program for older women with Congestive Heart Failure (CHF) and determine if certain factors influence adherence. Methods Women over the age of 65 with CHF attended an exercise program supervised by a physiotherapist. Quality of life was measured by the Minnesota Living with Heart Failure Questionnaire (MLHFQ) and severity of disease by the New York Heart Association (NYHA) Class. Subjects were classified into those who attended 90% or more of the sessions and those who attended less than 90% of the sessions. Results Fifty-one subjects were studied. Eight subjects did not attend any sessions. Of the 43 attendees, the average percentage of sessions attended was 87%. There were no significant differences between the two groups in age, MLHFQ or NYHA Class. There was only one adverse event out of 280 participant attendances. Conclusions The program had a high level of adherence in this population. Age, MLHFQ or NYHA Class did not impact on session attendance. Our data suggests this program is safe for this population. Further research is needed to determine other predictors of attendance and the examination of safety issues and long-term adherence to exercise in this population. 相似文献
64.
65.
Prodipto Pal Mate Mihanovi? Sven Molnar Huifeng Xi Guangyun Sun Saurav Guha Nina Jeran Andrea Tomljenovi? Ana Malnar Sa?a Missoni Ranjan Deka Pavao Rudan 《Croatian medical journal》2009,50(4):361-369
Aim
To perform a comprehensive evaluation of association of common genetic variants in candidate genes in the dopaminergic pathway with schizophrenia in a sample from Croatian population.Methods
A case-control association study was performed on 104 unrelated patients with schizophrenia recruited from a psychiatric hospital in Zagreb and 131 phenotypically normal Croatian subjects. Forty-nine tagging single nucleotide polymorphisms (tagSNPs) in 8 candidate genes in the dopaminergic pathway were identified from the HapMap database and tested for association. Genotyping was performed using the SNPlex platform. Statistical analysis was conducted to assess allelic and genotypic associations between cases and controls using a goodness of fit χ2 test and trend test, respectively; adjustment for multiple testing was done by permutation based analysis.Results
Significant allele frequency differences between schizophrenia cases and controls were observed at 4 tagSNPs located in the genes DRD5, HTR1B1, DBH, and TH1 (P < 0.005). A trend test also confirmed the genotypic association (P < 0.001) of these 4 tagSNPs. Additionally, moderate association (P < 0.05) was observed with 8 tagSNPs on SLC6A3, DBH, DRD4, SLC6A4, and COMT.Conclusions
Common genetic variants in genes involved in the dopaminergic pathway are associated with schizophrenia in the populations of Caucasian descent.Schizophrenia is a chronic, severe, and disabling brain disease affecting about 1% of the global population (1). There is substantial evidence that genetic factors are involved in the etiology of the disease (2). High heritability (~ 80%) and higher concordance in monozygotic (~ 50%) than in dizygotic (~ 17%) twins are strong indicators for an inherited basis of schizophrenia (3-5). During the past decade, numerous loci and plausible candidate genes have been identified by linkage and association studies. However, the findings have remained inconclusive (2,6). Like other complex diseases, a complex genetic etiology compounded by involvement of other non-genetic factors has hindered the precise identification of schizophrenia gene variants. Second, a major limitation in most association studies has been testing of a few variants within a gene of interest rather than a thorough assessment of the entire gene region. With the availability of the sequence of the genome and large body of data on human genetic variation from the HapMap project (7), it is now possible to undertake more comprehensive association studies.Genes involved in the dopamine pathway are biologically plausible candidates in schizophrenia susceptibility. In this study, we report on the association of single nucleotide polymorphisms (SNPs) in 8 dopaminergic genes (DRD4, DRD5, SLC6A3, SLC6A4, HTR1B, DBH, TH, and COMT) with schizophrenia in a Caucasian sample from Croatia. We performed a comprehensive association study using tagging SNPs (tagSNPs). Overall, 49 tagSNPs were identified from the HapMap database (7), 4 of which showed strong evidence of association with schizophrenia susceptibility. 相似文献66.
Diazoxide is a putative mitochondrial, ATP-sensitive potassium channel opener that has been implicated in neuroprotection in cerebral ischemia. Administered as pretreatment, diazoxide can attenuate ischemia-related neuronal injury, but little is known about the potential neuroprotective properties of the drug when it is given after the onset of an ischemic insult. In a previous study, we applied diazoxide after imposing chronic cerebral hypoperfusion by means of permanent, bilateral occlusion of the common carotid arteries (2VO) in rats. We observed that ischemia-induced learning impairment assessed in the Morris water maze, and microglial activation visualized by immunocytochemistry, were prevented by diazoxide as determined at 13 weeks after 2VO. However, dimethyl sulfoxide, the organic solvent of diazoxide also prevented memory deficits, without any effect on microglial activity. Therefore, we have repeated our experiments with the use of an inorganic solvent, aqueous NaOH solution in order to clarify the effect of diazoxide independent of dimethyl sulfoxide. The present results demonstrated that diazoxide alone did not improve learning performance, but it prevented microglial activation in the hippocampus 13 weeks after the onset of 2VO. These data provide evidence that post-treatment with diazoxide is not effective in impeding a long-term memory deficiency, but it can attenuate ischemia-induced microglial activation, independently of the solvent used. 相似文献
67.
The Anatomy and Ontogeny of the Head,Neck, Pectoral,and Upper Limb Muscles of Lemur catta and Propithecus coquereli (Primates): Discussion on the Parallelism Between Ontogeny and Phylogeny and Implications for Evolutionary and Developmental Biology 下载免费PDF全文
Rui Diogo Julia L. Molnar Timothy D. Smith 《Anatomical record (Hoboken, N.J. : 2007)》2014,297(8):1435-1453
68.
Going beyond “Basaloid neoplasm”: Fine needle aspiration cytology of epithelial‐myoepithelial carcinoma of the parotid gland 下载免费PDF全文
Stacy L. Molnar BS SCT CT Matthew A. Zarka MD Luis E. De Las Casas MD FASCP 《Diagnostic cytopathology》2016,44(5):422-425
Epithelial‐myoepithelial carcinoma (EMC) is a rare salivary gland malignancy with variable cytologic findings. Its rarity, variable morphologic findings, and similarities with more common salivary gland entities make it a difficult cytologic diagnosis. As the name signifies, the key feature of this tumor is presence of an epithelial and myoepithelial component. However, when one of these two components is scant on the fine needle aspiration (FNA) smears, it may be overlooked. We present a case from a 62 year‐old female who presented to the clinic with a parotid nodule and episodes of sharp, throbbing pain. A fine needle aspiration was performed which revealed a highly cellular specimen comprised primarily of aggregates of cells with small, round nuclei and scant to absent cytoplasm. Abundant hyaline stromal material was also noted. The case was signed out as basaloid neoplasm with a recommendation for surgical resection. The subsequent resection specimen revealed EMC. By reviewing the FNA specimen following the surgical resection of the tumor, we were able to utilize the benefit of hindsight to more clearly identify the subtle, biphasic components of the tumor. Diagn. Cytopathol. 2016;44:422–425. © 2016 Wiley Periodicals, Inc. 相似文献
69.
Activation of group I and group II metabotropic glutamate receptors (mGluRs) is thought to be required for long-term depression (LTD) of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor-mediated synaptic transmission in the perirhinal cortex. However, little is known about how activation of mGluRs leads to this form of synaptic plasticity. AMPA receptor phosphorylation has been implicated in several forms of modulation of synaptic transmission. In the CA1 area of the hippocampus, N-methyl-d-aspartate (NMDA) receptor-dependent LTD is associated with the reduced phosphorylation of the GluR1 AMPA receptor subunit at serine 845 (GluR1-S845). Immunoblot analysis of perirhinal cortical neurons using GluR1 and GluR1-S845 phosphorylation state specific antibodies showed that stimulation of adenylyl cyclase (AC) with forskolin (FSK) dramatically increased PKA-mediated phosphorylation of GluR1-S845. However, selective or simultaneous application of mGluR5 agonist (S)-3,5-dihydroxyphenylglycine (CHPG) and mGluR2/3 agonist (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG IV) did not produce detectable changes in GluR1-S845 phosphorylation. These results indicate that in the perirhinal cortex mGluR activation does not alter the phosphorylation state of GluR1-S845. Therefore, it is likely that the process involved in the modification of AMPA receptors in mGluR activation dependent LTD in the perirhinal cortex is mechanistically distinct from NMDA receptor-mediated LTD described in hippocampal neurons. 相似文献
70.
Csoma E Bácsi A Liu X Szabó J Ebbesen P Beck Z Kónya J Andirkó I Nagy E Tóth FD 《Journal of medical virology》2002,67(1):67-87
Human herpesvirus 6 (HHV-6) and human immunodeficiency virus type 1 (HIV-1) may interact during transplacental transmission of HIV-1. The placental syncytiotrophoblast layer serves as the first line of defense of the fetus against viruses. Patterns of replication of HHV-6 variant A (HHV-6A) and HIV-1 were analyzed in singly and dually infected human term syncytiotrophoblast cells cultured in vitro. For this purpose, the GS strain of HHV-6A and the Ba-L and IIIB strains of HIV-1 were used. HHV-6A replication was restricted at the level of early gene products in singly infected syncytiotrophoblasts, whereas no viral protein expression was found in cells infected with HIV-1 alone. Coinfection of syncytiotrophoblast cells with HHV-6A and HIV-1 resulted in production of infectious HIV-1. In contrast, no enhancement of HHV-6A expression was observed in cell cultures infected with both viruses. Uninfected syncytiotrophoblast cells were found to express CXCR4 and CCR3 but not CD4 or CCR5 receptors. Infection of syncytiotrophoblasts with HHV-6A did not induce CD4 expression and had no influence on chemokine receptor expression. Activation of HIV-1 from latency in coinfected cells was mediated by the immediate-early (IE)-A and IE-B gene products of HHV-6A. Open reading frames U86 and U89 of the IE-A region were able to activate HIV-1 replication in a synergistic manner. The data suggest that in vivo double infection of syncytiotrophoblast cells with HHV-6A and HIV-1 could contribute to the transplacental transmission of HIV-1 but not HHV-6A. 相似文献