全文获取类型
收费全文 | 63994篇 |
免费 | 5559篇 |
国内免费 | 5174篇 |
出版年
2023年 | 723篇 |
2022年 | 926篇 |
2021年 | 2963篇 |
2020年 | 2283篇 |
2019年 | 2799篇 |
2018年 | 2645篇 |
2017年 | 2047篇 |
2016年 | 2853篇 |
2015年 | 4093篇 |
2014年 | 4919篇 |
2013年 | 5051篇 |
2012年 | 6000篇 |
2011年 | 5455篇 |
2010年 | 3397篇 |
2009年 | 3102篇 |
2008年 | 3470篇 |
2007年 | 3110篇 |
2006年 | 2660篇 |
2005年 | 2256篇 |
2004年 | 1818篇 |
2003年 | 1729篇 |
2002年 | 1357篇 |
2001年 | 1110篇 |
2000年 | 1010篇 |
1999年 | 906篇 |
1998年 | 568篇 |
1997年 | 512篇 |
1996年 | 502篇 |
1995年 | 459篇 |
1994年 | 450篇 |
1993年 | 359篇 |
1992年 | 492篇 |
1991年 | 354篇 |
1990年 | 301篇 |
1989年 | 285篇 |
1988年 | 230篇 |
1987年 | 208篇 |
1986年 | 191篇 |
1985年 | 166篇 |
1984年 | 119篇 |
1983年 | 128篇 |
1982年 | 88篇 |
1981年 | 45篇 |
1980年 | 52篇 |
1979年 | 63篇 |
1977年 | 36篇 |
1976年 | 46篇 |
1974年 | 54篇 |
1973年 | 45篇 |
1972年 | 54篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
Janne Alahuhta Sarian Kosten Munemitsu Akasaka Dominique Auderset Mattia M. Azzella Rossano Bolpagni Claudia P. Bove Patricia A. Chambers Eglantine Chappuis John Clayton Mary de Winton Frauke Ecke Esperança Gacia Gana Gecheva Patrick Grillas Jennifer Hauxwell Seppo Hellsten Jan Hjort Mark V. Hoyer Christiane Ilg Agnieszka Kolada Minna Kuoppala Torben Lauridsen En Hua Li Balázs A. Lukács Marit Mjelde Alison Mikulyuk Roger P. Mormul Jun Nishihiro Beat Oertli Laila Rhazi Mouhssine Rhazi Laura Sass Christine Schranz Martin Søndergaard Takashi Yamanouchi Qing Yu Haijun Wang Nigel Willby Xiao Ke Zhang Jani Heino 《Journal of Biogeography》2017,44(8):1758-1769
12.
Mengnan Wang Dongjie Li Mingyue Zhang Wenzhi Yang Yali Cui Shijie Li 《Animal genetics》2015,46(4):354-360
The CDKN1C gene encodes a cyclin‐dependent kinase inhibitor and is one of the key genes involved in the development of Beckwith–Wiedemann syndrome and cancer. In this study, using a direct sequencing approach based on a single nucleotide polymorphism (SNP) at genomic DNA and cDNA levels, we show that CDKN1C exhibits monoallelic expression in all seven studied organs (heart, liver, spleen, lung, kidney, muscle and subcutaneous fat) in cattle. To investigate how methylation regulates imprinting of CDKN1C in cattle, allele‐specific methylation patterns in two putative differential methylation regions (DMRs), the CDKN1C DMR and KvDMR1, were analyzed in three tissues (liver, spleen and lung) using bisulfite sequencing PCR. Our results show that in the CDKN1C DMR both parental alleles were unmethylated in all three analyzed tissues. In contrast, KvDMR1 was differentially methylated between the two parental alleles in the same tissues. Statistical analysis showed that there is a significant difference in the methylation level between the two parental alleles (P < 0.01), confirming that this region is the DMR of KvDMR1 and that it may be correlated with CDKN1C imprinting. 相似文献
13.
14.
15.
16.
<正>Chemotherapy employs chemical substances to interfere with the growth of cancer cells,and is a major treatment strategy in human cancer including acute myeloid leukemia(AML).Although they often effectively kill fast-dividing tumor cells,chemotherapeutic drugs also profoundly affect 相似文献
17.
Dyslipidemia is a strong risk factor for cardiovascular disease among patients with type 2 diabetes (T2D). The aim of this study was to identify lipid-related genetic variants in T2D patients of Han Chinese ancestry. Among 4,908 Chinese T2D patients who were not taking lipid-lowering medications, single nucleotide polymorphisms (SNPs) in seven genes previously found to be associated with lipid traits in genome-wide association studies conducted in populations of European ancestry (ABCA1, GCKR, BAZ1B, TOMM40, DOCK7, HNF1A, and HNF4A) were genotyped. After adjusting for multiple covariates, SNPs in ABCA1, GCKR, BAZ1B, TOMM40, and HNF1A were identified as significantly associated with triglyceride levels in T2D patients (P < 0.05). The associations between the SNPs in ABCA1 (rs3890182), GCKR (rs780094), and BAZ1B (rs2240466) remained significant even after correction for multiple testing (P = 8.85×10−3, 7.88×10−7, and 2.03×10−6, respectively). BAZ1B (rs2240466) also was associated with the total cholesterol level (P = 4.75×10−2). In addition, SNP rs157580 in TOMM40 was associated with the low-density lipoprotein cholesterol level (P = 6.94×10−3). Our findings confirm that lipid-related genetic loci are associated with lipid profiles in Chinese patients with type 2 diabetes. 相似文献
18.
19.
Eun Jin Park Joon Young Song Min Ju Choi Ji Ho Jeon Jah-yeon Choi Tae Un Yang Kyung Wook Hong Ji Yun Noh Hee Jin Cheong Woo Joo Kim 《The Korean journal of parasitology》2014,52(4):425-428
A 45-year-old-male who had underlying ulcerative colitis and presented with fever and dry cough. Initially, the patient was considered to have invasive aspergillosis due to a positive galactomannan assay. He was treated with amphotericin B followed by voriconazole. Nevertheless, the patient deteriorated clinically and radiographically. The lung biopsy revealed eosinophilic pneumonia, and ELISA for Toxocara antigen was positive, leading to a diagnosis of pulmonary toxocariasis. After a 10-day treatment course with albendazole and adjunctive steroids, the patient recovered completely without any sequelae. Pulmonary toxocariasis may be considered in patients with subacute or chronic pneumonia unresponsive to antibiotic agents, particularly in cases with eosinophilia. 相似文献
20.
Justyna McIntyre Mary P. McLenigan Ekaterina G. Frank Xiaoxia Dai Wei Yang Yinsheng Wang Roger Woodgate 《The Journal of biological chemistry》2015,290(45):27332-27344
Human DNA polymerases (pols) η and ι are Y-family DNA polymerase paralogs that facilitate translesion synthesis past damaged DNA. Both polη and polι can be monoubiquitinated in vivo. Polη has been shown to be ubiquitinated at one primary site. When this site is unavailable, three nearby lysines may become ubiquitinated. In contrast, mass spectrometry analysis of monoubiquitinated polι revealed that it is ubiquitinated at over 27 unique sites. Many of these sites are localized in different functional domains of the protein, including the catalytic polymerase domain, the proliferating cell nuclear antigen-interacting region, the Rev1-interacting region, and its ubiquitin binding motifs UBM1 and UBM2. Polι monoubiquitination remains unchanged after cells are exposed to DNA-damaging agents such as UV light (generating UV photoproducts), ethyl methanesulfonate (generating alkylation damage), mitomycin C (generating interstrand cross-links), or potassium bromate (generating direct oxidative DNA damage). However, when exposed to naphthoquinones, such as menadione and plumbagin, which cause indirect oxidative damage through mitochondrial dysfunction, polι becomes transiently polyubiquitinated via Lys11- and Lys48-linked chains of ubiquitin and subsequently targeted for degradation. Polyubiquitination does not occur as a direct result of the perturbation of the redox cycle as no polyubiquitination was observed after treatment with rotenone or antimycin A, which both inhibit mitochondrial electron transport. Interestingly, polyubiquitination was observed after the inhibition of the lysine acetyltransferase KATB3/p300. We hypothesize that the formation of polyubiquitination chains attached to polι occurs via the interplay between lysine acetylation and ubiquitination of ubiquitin itself at Lys11 and Lys48 rather than oxidative damage per se. 相似文献