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排序方式: 共有8747条查询结果,搜索用时 11 毫秒
91.
Gaetana Paolella Silvia Sposito Antonio Massimiliano Romanelli Ivana Caputo 《International journal of molecular sciences》2022,23(14)
Type 2 transglutaminase (TG2) is the main autoantigen in coeliac disease (CD), a widespread inflammatory enteropathy caused by the ingestion of gluten-containing cereals in genetically predisposed individuals. As a consequence, serum antibodies to TG2 represent a very useful marker in CD diagnosis. However, TG2 is also an important player in CD pathogenesis, for its ability to deamidate some Gln residues of gluten peptides, which become more immunogenic in CD intestinal mucosa. Given the importance of TG2 enzymatic activities in CD, several studies have sought to discover specific and potent inhibitors that could be employed in new therapeutical approaches for CD, as alternatives to a lifelong gluten-free diet. In this review, we summarise all the aspects regarding TG2 involvement in CD, including its enzymatic reactions in pathogenesis, the role of anti-TG2 antibodies in disease management, and the exploration of recent strategies to reduce deamidation or to use transamidation to detoxify gluten. 相似文献
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目的 探讨小麦麸皮微波处理灭酶对全麦粉面筋品质特性和流变学特性的影响.方法 以中高筋小麦为原料,对麸皮微波处理后再回添到小麦粉中制得全麦粉,设置麸皮水分含量、微波处理时间和麸皮厚度3个变量因素,固定其中2个变量因素,探讨另1个变量因素对全麦粉中面筋特性和流变学特性的影响.结果 麸皮水分含量对湿面筋含量、面筋吸水率、面团... 相似文献
95.
Bowen Yan Haoyu Zheng Yuwei Sang Yan Wang Jian Sun Fengcheng Li Jiayu Wang Xiaoxue Wang 《International journal of molecular sciences》2022,23(16)
Lesion mimic mutants are an ideal model system for elucidating the molecular mechanisms of programmed cell death and defense responses in rice. In this study, we identified a lesion mimic mutant termed miner infection like 1-1 (mil1-1). The mil1-1 exhibited lesions on the leaves during development, and the chloroplasts of mil1-1 leaves were disrupted. Reactive oxygen species were found to accumulate in mil1-1 leaves. Cell death and DNA fragmentation were observed in mil1-1 leaves, indicating that the cells in the spots of mil1-1 leaves experienced programmed cell death. Most agronomic traits decreased in mil1-1, suggesting that the growth retardation in mil1-1 caused reduced per-plant grain yield. However, the mutation of MIL1 activated the expression of pathogen response genes and enhanced resistance to bacterial blight. The MIL1 gene was cloned using the positional cloning approach. A missense mutation 751 bp downstream of ATG was found in mil1-1. The defects of mil1-1 were able to be rescued by delivering a wild-type MIL1 gene into mil1-1. MIL1 encoded hydroperoxide lyase 3 (OsHPL3), and the expression of OsHPL3 was induced via hormone and abiotic stresses. Our findings provide insights into the roles of MIL1 in regulating programmed cell death, development, yield, and defense responses in rice. 相似文献
96.
基于计算机视觉的大米粒形识别方法 总被引:3,自引:1,他引:2
提出了利用计算机视觉系统代替人眼识别整粒大米和碎大米粒形的方法。设计了一套基于计算机视觉技术的大米粒形识别装置,采用灰度变换、阈值分割、平滑处理等图像处理方法获取大米的粒形图像,然后根据大米的粒形特点提取了米粒的面积、周长、长、宽等16个特征参数,采用主成分分析方法对提取的特征参数进行处理,以前三个主成分综合所有粒形特征参数,作为BP神经网络的输入特征值对网络进行训练和大米粒形识别。试验结果表明:该方法对整粒米识别的准确率为98.67%;对碎米识别的准确率为92.09%。 相似文献
97.
Tao Yang Pei Wang Qin Zhou Yingxin Zhong Xiao Wang Jian Cai Mei Huang Dong Jiang 《International journal of molecular sciences》2022,23(15)
Starch–gluten interactions are affected by biopolymer type and processing. However, the differentiation mechanisms for gluten–starch interactions during heating have not been illuminated. The effects of glutens from two different wheat flours (a weak-gluten (Yangmai 22, Y22) and a medium-strong gluten (Yangmai 16, Y16)) on starch’s (S) structural and physicochemical properties during heating and their molecular interactions were investigated in this study. The results showed that gluten hindered the gelatinization and swelling of starch during heating when temperature was below 75 °C, due to competitive hydration and physical barriers of glutens, especially in Y22. Thus, over-heating caused the long-range molecular order and amylopectin branches of starch to be better preserved in the Y22-starch mixture (Y22-S) than in the Y16-starch mixture (Y16-S). Meanwhile, the starch’s degradation pattern during heating in turn influenced the polymerization of both glutens. During heating, residual amylopectin branching points restricted the aggregation and cross-linking of gluten proteins due to steric hindrance. More intense interaction between Y16 and starch during heating mitigated the steric hindrance in starch–gluten networks, which was due to more residual short-range ordered starch and hydrogen bonds involved in the formation of starch–gluten networks in Y16-S during heating. 相似文献
98.
Shaoming Liang Shanbin Xu Di Qu Luomiao Yang Jingguo Wang Hualong Liu Wei Xin Detang Zou Hongliang Zheng 《International journal of molecular sciences》2022,23(15)
Caffeic acid O-methyltransferase (COMT) is one of the core enzymes involved in lignin synthesis. However, there is no systematic study on the rice COMT gene family. We identified 33 COMT genes containing the methyltransferase-2 domain in the rice genome using bioinformatic methods and divided them into Group I (a and b) and Group II. Motifs, conserved domains, gene structure and SNPs density are related to the classification of OsCOMTs. The tandem phenomenon plays a key role in the expansion of OsCOMTs. The expression levels of fourteen and thirteen OsCOMTs increased or decreased under salt stress and drought stress, respectively. OsCOMTs showed higher expression levels in the stem. The lignin content of rice was measured in five stages; combined with the expression analysis of OsCOMTs and multiple sequence alignment, we found that OsCOMT8, OsCOMT9 and OsCOMT15 play a key role in the synthesis of lignin. Targeted miRNAs and gene ontology annotation revealed that OsCOMTs were involved in abiotic stress responses. Our study contributes to the analysis of the biological function of OsCOMTs, which may provide information for future rice breeding and editing of the rice genome. 相似文献
99.
以莲子和糯米为原料,通过不同条件对比分析对莲子糯米酒的酿造工艺进行探讨。结果表明:糯米蒸煮时间20 min、莲子蒸煮时间30 min,莲子糯米质量比为1∶2,料水比为1∶0.7,按原料质量百分比添加10%的麦曲、1.5%的酒曲和0.6%的淀粉酶,主发酵时间为7 d,温度28℃的工艺条件下,后发酵23 d,可酿制莲子糯米酒。其成品酒的各项理化指标与感官指标均符合国家标准GB/T 13662-2008的要求,具有独特的香气与风味,总酚含量为863.71μg/m L,总黄酮含量为135.12μg/m L,保健成分含量得到了提高。 相似文献
100.