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991.
992.
Lee JW Bang KH Kim YC Seo AY Jo IH Lee JH Kim OT Hyun DY Cha SW Cho JH 《Molecular biology reports》2012,39(1):729-736
Cleaved amplified polymorphic sequence (CAPS) marker system using mitochondrial consensus primers was applied for molecular
identification of Korean ginseng cultivars (Panax ginseng). Initially, a total of 34 primers were tested to six Korean ginseng cultivars and two foreign Panax species, P. quinquefolius and P. notoginseng. In the polymerase chain reaction (PCR) amplification results, four primers (mt7, mt11, mt13, and mt18) generated co-dominant
polymorphic banding patterns discriminating the Korean ginseng cultivars from P. quinquefolius and P. notoginseng. In the CAPS analysis results, the majority of the cleaved PCR products also yielded additional latent polymorphisms between
the Korean ginseng cultivars and two foreign Panax species. Specific latent CAPS polymorphisms for cultivar Gopoong and Chunpoong were detected from internal region amplified
with mt9 primer by treating HinfI and Tsp509I endonucleases, respectively. Sequencing analysis revealed that the length of amplified region of Korean ginseng cultivars
was 2,179 bp, and those of P. quinquefolius and P. notoginseng were 2,178 and 2,185 bp, respectively. Blast search revealed that the amplified region was a mitochondrial cytochrome oxidase
subunit 2 (cox2) gene intron II region. Nineteen single nucleotide polymorphisms (SNP) including each specific SNP for Gopoong and Chunpoong,
and three insertion and deletion (InDel) polymorphisms were detected by sequence alignment. The CAPS markers developed in
this study, which are specific to Gopoong and Chunpoong, and between the Korean ginseng cultivars and two foreign Panax species, will serve as a practical and reliable tool for their identification, purity maintenance, and selection of candidate
lines and cultivars. 相似文献
993.
Generation of the 3′ overhang is a critical event during homologous recombination (HR) repair of DNA double strand breaks. A 5′–3′ nuclease, NurA, plays an important role in generating 3′ single-stranded DNA during archaeal HR, together with Mre11–Rad50 and HerA. We have determined the crystal structures of apo- and dAMP-Mn2+-bound NurA from Pyrococcus furiousus (Pf NurA) to provide the basis for its cleavage mechanism. Pf NurA forms a pyramid-shaped dimer containing a large central channel on one side, which becomes narrower towards the peak of the pyramid. The structure contains a PIWI domain with high similarity to argonaute, endoV nuclease and RNase H. The two active sites, each of which contains Mn2+ ion(s) and dAMP, are at the corners of the elliptical channel near the flat face of the dimer. The 3′ OH group of the ribose ring is directed toward the channel entrance, explaining the 5′–3′ nuclease activity of Pf NurA. We provide a DNA binding and cleavage model for Pf NurA. 相似文献
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995.
Yoon D Kim YJ Cui WY Van der Vaart A Cho YS Lee JY Ma JZ Payne TJ Li MD Park T 《Human genetics》2012,131(6):1009-1021
Diseases related to smoking are the second leading cause of death in the world. Cigarette smoking is a risk factor for several diseases such as cancer and cardiovascular and respiratory disorders. Despite increasing evidence of genetic determination, the susceptibility genes and loci underlying various aspects of smoking behavior are largely unknown. Moreover, almost all reported genome-wide association studies (GWASs) have been performed on samples of European origin, limiting the applicability of the results to other ethnic populations. In this first GWAS on smoking behavior in an Asian population, after analyzing 8,842 DNA samples from the Korea Association Resource project with 352,228 single nucleotide polymorphisms (SNPs) genotyped for each sample, we identified 8 SNPs significantly associated with smoking initiation (SI) and 4 with nicotine dependence (ND). Because of the current unavailability of an independent Asian smoking sample, we replicated the discoveries in independent samples of European-American and African-American origin. Of the 12 SNPs examined in the replicated samples, we identified two SNPs, in the regulator of G-protein signaling 17 gene (rs7747583, p value(meta)?=?6.40?×?10(-6); rs2349433, p value(meta)?=?5.57?×?10(-6)), associated with SI. Also, we found two SNPs significantly associated with ND; one in the FERM domain containing 4A (rs4424567, p value(meta)?=?2.30?×?10(-6)) and the other at 7q31.1 (rs848353, p value(meta)?=?9.16?×?10(-8)). These SNPs represent novel targets for examination of smoking behavior and warrant further investigation using independent samples. 相似文献
996.
Plasmid DNA vaccination is an attractive way to elicit T cell responses against infectious agents and tumor cells. DNA constructs
can be designed to contain multiple T cell epitopes to generate a diverse immune response to incorporate numerous antigens
and to reduce limitations due to MHC restriction into a single entity. We have prepared cDNA plasmid constructs containing
several mouse T cell epitopes connected by either furin-sensitive or furin-resistant linkers and studied the effects of a
cationic cell-penetrating sequence from HIV-tat. Significant CD8 T cell responses were obtained with multi-epitope DNA vaccines
followed by in vivo electroporation regardless of the type of linker used and whether the construct had the HIV-tat sequence.
The magnitude of immune responses was very similar to all CD8 T cell epitopes contained within each vaccine construct, indicating
the absence of immunodominance. Incorporating a T helper epitope into the constructs increased the T cell responses. Prophylactic
and therapeutic antitumor responses against B16 melanoma were obtained using a construct containing epitopes from melanosomal
proteins, indicating that this vaccination was successful in generating responses to self-antigens that potentially may be
subjected to immune tolerance. These findings are useful for designing DNA vaccines for a multitude of diseases where T lymphocytes
play a protective or therapeutic role. 相似文献
997.
Anaerobic gram-negative oral bacteria such as Treponema denticola, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Campylobacter rectus, and Fusobacterium nucleatum are closely associated with periodontal diseases. We measured the relative population (bacterial levels) of these oral pathogens in subgingival tissues of patients at different stages of Korean chronic periodontal diseases. We divided the individuals into those with chronic gingivitis (G), moderate periodontitis (P1), severe periodontitis (P2), and normal individuals (N) (n?=?20 for each group) and subgingival tissue samples were collected. We used real-time PCR with TaqMan probes to evaluate the change of periodontal pathogens among different stages of periodontitis. Bacterial levels of A. actinomycetemcomitans and C. rectus are significantly increased in individuals with chronic gingivitis and moderate periodontitis, but unchanged in severe periodontitis patients. These results suggest that analyzing certain bacterial levels among total oral pathogens may facilitate understanding of the role of periodontal bacteria in the early stages of periodontitis. 相似文献
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