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11.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts 下载免费PDF全文
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亨廷顿病(Huntington's disease, HD)是神经退行性疾病(neurodegenerative disorders)中一种单基因遗传病,由亨廷顿基因(the huntingtin gene, HTT)第一个外显子中的CAG三核苷酸序列重复扩增引起,尚无法治愈。HTT编码的蛋白产物被称为亨廷顿蛋白(Huntingtin protein, Htt)。突变亨廷顿蛋白(mutated huntingtin protein, mHtt)容易形成聚集体,具有毒性,导致一系列细胞学异常和神经元功能障碍。microRNA(miRNA)在基因转录后水平调控中起重要作用,其表达的改变与HD病理过程有关,成为治疗HD的潜在生物标志物。近年来,对一些特定miRNA在HD中调控机制及靶基因预测方面的研究可为HD提供潜在的治疗方法。本文就miRNA在HD中的相关研究进展进行综述。 相似文献
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Nie Xin-min Gui Rong Zhao Hong-shan Ma Da-long Li Deng-qing Yuan Hong Huang Zu-fa 《中南工业大学学报(英文版)》2005,12(1):310-312
Objective Tacrolimus is an immunosuppressive drug with narrow therapeutic range and wide interindividual variation in its pharmacokinetics.
Tacrolimus is a substrate of cytochrome P450(CYP)3A5. The aim of this study was to evaluate whether the A6986G polymorphism
is associated with tacrolimus concentration /dose ratio. Methods Fifty-two Chinese renal transplant patients were enrolled in this study. Their body weight, dosage and concentration of tacrolimus
were observed. CYP3A5 genotype was determined by polymerase chain reaction followed by restriction fragment length polymorphism
analysis. Results A significant association was found between tacrolimus levels per dose/kg/d and CYP3A5 gene A6986G polymorphism (P<0.001). The CYP3A5 * 3 * 3 patients have a significantly higher tacrolimus level/dose than CYP3A5 * 1 * 1 and CYP3A5 * 1
* 3. Conclusions CYP3A5 gene A6986G polymorphism is associated with tacrolimus pharmacokinetics and dose requirements. Pharmacogenetic methods
could be employed prospectively to help the dose selection and to individualize immunosuppressive therapy according to the
result.
Foundation item: Project (03GZ3072) supported by the Science and Technology Department of Hunan Province; project (2004035206) supported by
the China Postdoctoral Foundation and project (30300383) supported by the National Natural Sciences Foundation of China 相似文献
16.
蒋成德 《徐州工程学院学报》2008,23(6):85-88
孔子是否删诗,这是一个历史遗留问题。司马迁首言在前,孔颖达怀疑在后。宋之后,争议遂起,延至近代。今人夏传才先生断日:孔子是否删诗,“在没有发掘出新史料的情况下,哪怕再争论八百年,也是搞不清楚的”。以此止息纷争。话虽不错,但问题并没有解决。我认为,在没有发掘出新史料的情况下,可以从《左传》入手,来考察孔子是否删诗。 相似文献
17.
Genetically modified starter and protective cultures 总被引:1,自引:0,他引:1
Modern approaches towards starter and protective culture improvement rely on advances in molecular biology. For most microorganisms used for food production, gene technological methods have been well developed. By recombinant DNA technology, ‘tailor-made’ starter and protective cultures may be constructed so as to combine technically desirable features. A single strain which normally would fail to accomplish a given ‘wtask’ may now be improved so as to meet a set of requirements necessary for a specific production or preservation process (e.g. wholesomeness, no off-flavour production, overproduction of bacteriocins or particular enzymes). In addition, undesirable properties (e.g. mycotoxin or antibiotic production by cheese moulds) may be eliminated by techniques such as ‘gene disruption’. 相似文献
18.
We address the problems of noise and huge data sizes in microarray images. First, we propose a mixture model for describing the statistical and structural properties of microarray images. Then, based on the microarray image model, we present methods for denoising and for compressing microarray images. The denoising method is based on a variant of the translation-invariant wavelet transform. The compression method introduces the notion of approximate contexts (rather than traditional exact contexts) in modeling the symbol probabilities in a microarray image. This inexact context modeling approach is important in dealing with the noisy nature of microarray images. Using the proposed denoising and compression methods, we describe a near-lossless compression scheme suitable for microarray images. Results on both denoising and compression are included, which show the performance of the proposed methods. Further experiments using the results of the proposed near-lossless compression scheme in gene clustering using cell-cycle microarray data for S. cerevisiae showed a general improvement in the clustering performance, when compared with using the original data. This provides an indirect validation of the effectiveness of the proposed denoising method. 相似文献
19.
国内外微生物采油技术综述 总被引:24,自引:4,他引:20
生物技术特别是微生物采油技术,已经引起了石油工程技术人员的空前关注,目前在国内外开展的微生物采油先导性矿场试验已初见成效,较为典型的当数美国和俄罗斯,我国的吉林、胜利等油田也进行了矿场试验,增油效果令人鼓舞。同时,随着科学技术的发展,一些先进的微生物学研究工具已经进入微生物采油技术的研究领域,如分子生物学、示踪剂及可视化技术等已经成为微生物采油机理研究的重要工具。相关的石油烃降解理论以及建立数学模型等也取得了系列成果。微生物采油的应用也从过去的单井处理逐渐向整个区块或油田发展,并见到了明显效果。 相似文献
20.
Salinger Walter L.; Ladrow Pamela; Wheeler Catherine 《Canadian Metallurgical Quarterly》2003,117(6):1257
Reeler (rl/rl) and reeler/wild-type (+/rl) mice synthesize Reln at subnormal rates, as do patients with schizophrenia, bipolar disorder, and autism, thereby forming the basis for a Reln hypothesis for vulnerability to these psychopathologies and justifying attention to the behavioral phenotypes of Reln-deficient mice. Tests of gait, emotionality, social aggression, spatial working memory, novel-object detection, fear conditioning, and sensorimotor reflex modulation revealed the behavioral phenotype of rl/rl, but not +/rl, mice to be different from that of wild-type (+/+) mice. These results reveal no effect of Reln gene dosage and provide significant challenges to both the Reln and the neurodevelopmental hypotheses of the etiology of major psychopathologies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献