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991.
A series of novel arylsulfonylpropargylglycinamide derivatives was investigated as thrombin inhibitors in which the SAR was focused on substituents at the acetylenic terminus. Several compounds in this series were identified as potent thrombin inhibitors (Ki up to 5 nM) that are highly selective over trypsin and other serine proteases as well.  相似文献   
992.
Cardiovascular disease has been the leading cause of death worldwide for the last few decades. Even with therapid progression of the biomedical field, conquering/managing cardiovascular disease is not an easy task because it is multifactorial disease. One of the key players of the development and progression of numerous diseases is micro RNA(mi RNA). These small, non-coding RNAs bind to target m RNAs to inhibit translations of and/or degrade the target m RNAs, thus acting as negative regulators of gene expressions. Accumulating evidence indicates that non-physiological expressions of mi RNAs contribute to both development and progression of cardiovascular diseases. Since even a single mi RNA can have multiple targets, dysregulation of mi RNAs can lead to catastrophic changes of proteins that may be important for maintaining physiologic conditions of cells, tissues, and organs. Current knowledge on the role of mi RNAs in cardiovascular disease is mostly based on the observational data such as microarray of mi RNAs in animal disease models, thus relatively lacking insight of how such dysregulation of mi RNAs is initiated and regulated. Consequently, future research should aim to elucidate the more comprehensive mechanisms of mi RNA dysregulation during pathogenesis of the cardiovascular system so that appropriate countermeasures to prevent/manage cardiovascular disease can be developed.  相似文献   
993.
Nervous necrosis virus (NNV) causes viral encephalopathy and retinopathy, a devastating disease of many species of cultured marine fish worldwide. In this study, we used the dimorphic non-pathogenic yeast Yarrowia lipolytica as a host to express the capsid protein of red-spotted grouper nervous necrosis virus (RGNNV-CP) and evaluated its potential as a platform for vaccine production. An initial attempt was made to express the codon-optimized synthetic genes encoding intact and N-terminal truncated forms of RGNNV-CP under the strong constitutive TEF1 promoter using autonomously replicating sequence (ARS)-based vectors. The full-length recombinant capsid proteins expressed in Y. lipolytica were detected not only as monomers and but also as trimers, which is a basic unit for formation of NNV virus-like particles (VLPs). Oral immunization of mice with whole recombinant Y. lipolytica harboring the ARS-based plasmids was shown to efficiently induce the formation of IgG against RGNNV-CP. To increase the number of integrated copies of the RGNNV-CP expression cassette, a set of 26S ribosomal DNA-based multiple integrative vectors was constructed in combination with a series of defective Ylura3 with truncated promoters as selection markers, resulting in integrants harboring up to eight copies of the RGNNV-CP cassette. Sucrose gradient centrifugation and transmission electron microscopy of this high-copy integrant were carried out to confirm the expression of RGNNV-CPs as VLPs. This is the first report on efficient expression of viral capsid proteins as VLPs in Y. lipolytica, demonstrating high potential for the Y. lipolytica expression system as a platform for recombinant vaccine production based on VLPs.  相似文献   
994.
Deoxynivalenol (DON), a typical mycotoxin, is a substance that is biosynthesized mainly by the Fusarium species. It is usually found in wheat and other grains grown in the field. When it enters the human body, it causes severe diarrhea, abdominal pain, vomiting, and even death. In addition, DON is known to induce inflammation of the small and large intestine, and is also associated with the occurrence of cancer. However, until recently, the effects of DON on the human skin were unknown. To investigate how DON affects HaCaT, human immortalized keratinocytes, we used CCK-8 assay and a quantitative real-time RT-PCR method to detect changes in the expression of tight junctions and skin cell regulatory proteins. The CCK-8 assay was performed to determine the growth inhibitory concentration of keratinocytes by DON. DON affected the cell survival rate from 1 μM in a concentration dependent manner, with the minimum set as 1 μM and the maximum as 4 μM for all experiments. DON inhibited the mRNA expression of filaggrin by up to 71% and SERPINA1 up to 75%. The expression of AQP3 was reduced by up to 93% compared to the untreated control group. This may cause problems in the pH control function of the skin and weaken the function of moisturizing. In addition, in the presence of DON, the gene expression of claudin 1 and claudin 8, which are important proteins in the regulation of intercellular skin barrier, decreased by up to 47 and 80%, respectively. Snail/ Slug, suppressors of the claudin gene expression, each increased up to 625 and 974%, respectively. Also, the MMP9 gene increased by up to 515% in a concentrationdependent manner, perhaps causing a weakness of the barrier function of the skin. These results suggest that DON may causing the development of atopic skin by impairing the skin barrier and pH control of skin, as well as intestinal inflammation diseases. Therefore, particular attention should be paid to DON contamination during the development of cosmetic ingredients using grains.  相似文献   
995.
Species within the coreid clade (Hemiptera: Coreidae) can often be observed competing in intrasexual competitions over access to mates and territories. Coreids that partake in these competitions typically possess sexually dimorphic hind legs that are used to strike and squeeze their rivals. In addition to their weaponized legs, some coreid species also possess sexually dimorphic abdominal tubercles, which are assumed to be sexually selected weapons. Still, much remains unknown about the morphology of these structures. Here, using the species Mictis longicornis Westwood, we investigate the frequency distribution and static allometry of abdominal thickness, a measure that includes tubercle length. Furthermore, we also investigate the morphological relationship between abdominal tubercles and weaponized hind legs. We find that male abdominal thickness is best explained by a bimodal distribution, thereby describing the first observed male polymorphism in the coreid clade; a phenomenon typically associated with alternative reproductive tactics. Additionally, we find that major males are characterized primarily by having large weaponized legs and abdominal tubercles, which further suggests that abdominal tubercles are used in male–male competition.  相似文献   
996.
Postmortem pH is a main factor influencing the meat quality in pigs. This study investigated the association of postmortem pH with single-nucleotide polymorphisms (SNPs) in the fourth member of the short-chain dehydrogenase/reductase family (DHRS4), the first member of serpin peptidase inhibitor, clade G (complement inhibitor) (SERPING1), and the apolipoprotein R precursor (APOR) genes in Berkshire pigs. The study included 437 pigs, and genotyping was conducted using the GoldenGate Assay (Illumina, San Diego, CA, USA). DHRS4, SERPING1, and APOR polymorphisms were significantly associated with pH45 or pH24 (p?SERPING1 was also statistically significantly associated with water holding capacity (p?DHRS4, SERPING1, and APOR genes have potential for use as genetic markers for the meat quality in pigs.  相似文献   
997.
The Cf-9 gene in the tomato is known to confer resistance against leaf mold disease caused by Cladosporium fulvum, and a gene-based marker targeted to the Cf-9 allele has been widely used as a crop protection approach. However, we found this marker to be misleading in genotyping. Therefore, we developed new single-nucleotide polymorphism (SNP) and insertion and deletion (InDel) markers targeted to the Cf-9 allele in order to increase genotyping accuracy and facilitate high-throughput screening. The DNA sequences of reported Cf-9, cf-9, Cf-0, and closely related Cf-4 alleles were compared, and two functional and non-synonymous SNPs were found to distinguish the Cf-9 resistance allele from the cf-9, Cf-0, and Cf-4 alleles. An SNP marker including these two SNPs was developed and applied to the genotyping of 33 tomato cultivars by high-resolution melting analysis. Our SNP marker was able to select all three Cf-9 genotypes (resistant, heterozygous, and susceptible alleles). Interestingly, two cultivars were grouped separately from these three genotypes. To further examine this outgroup, we preformed polymerase chain reaction (PCR) on two InDel regions identified by sequence comparison of the Cf-9 and Cf-4 genes. The band patterns revealed that these two cultivars carried Cf-4 rather than Cf-9 alleles and that three cultivars classified in the Cf-9 resistance group actually carried both Cf-9 and Cf-4 genes. To determine whether these genotyping results were consistent with disease resistance phenotypes, we examined the induction of a hypersensitive response by transiently expressing the corresponding effector genes, and found that the results matched perfectly with the genotyping results. These findings indicate that the combination of our SNP and InDel markers allows resistant Cf-9 alleles to be distinguished from cf-9 and Cf-4 alleles, which will be useful for marker-assisted selection of tomato cultivars resistant to C. fulvum.  相似文献   
998.
In this paper, we present a framework that can provide users with a simple, convenient and powerful way to deploy multiple message queue system on demand in a Hadoop cluster. Specifically, we are leveraging the Apache Kafka which is one of the state of art distributed message queue systems that can achieve high throughput, low latency, and good load balancing. Our framework provides automation of setting up and starting Kafka brokers on the fly and users can leverage the framework to quickly adopt Kafka without spending much efforts on installation and configuration challenges. In addition, the framework supports users to run their Kafka-based applications without detailed knowledge about the Hadoop YARN APIs and underlying mechanisms. We present a use case of the framework to evaluate Kafka’s performance with various test cases and working scenarios. The experimental results allow Kafka’s potential users to perceive the influences of different settings on the queuing performance.  相似文献   
999.
1000.
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