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61.
62.
Nail patella syndrome (NPS) is an autosomal dominant disorder characterized by nail malformations, patellar apoplasia, or patellar hypoplasia. Mutations within the LMX1B gene are found in 85% of families with NPS; thus, this gene has been characterized as the causative gene of NPS. In this study, we identified a heterozygous microdeletion of the entire LMX1B gene using multiplex ligation-dependent probe amplification (MLPA) in a Chinese family with NPS. The determination of the deletion breakpoints by Illumina genome-wide DNA analysis beadchip showed that the deletion was located in chromosome 9q33.3 and spanned about 0.66 Mb in size. This heterozygous deletion provides strong evidence for haploinsufficiency as the pathogenic mechanism of NPS.  相似文献   
63.
To test the hypothesis that odorant quality perception is altered in olfactory marker protein (OMP)-null mice, we trained and tested adult OMP-null and control mice, using a 5-odorant identification confusion matrix task (animal odorant confusion matrix [AOCM]). On average, control and null mice performed the task at equivalent levels. The composite 5?×?5 response matrix from 40 testing sessions for each subject (both OMP-null and control) was compared with that of every other subject, yielding a dissimilarity matrix of AOCM responses. A multidimensional scaling (MDS) analysis of the dissimilarity data yielded a 4-dimensional solution, with each mouse occupying a point in MDS animal space. Statistical analysis demonstrated significant effects of genotype in determining the location of a mouse in the MDS space. These data suggest, therefore, that compared with that of controls, odorant quality perception is altered in the OMP-null mouse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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65.
Two inherited lethal disorders, bovine leukocyte adhesion deficiency (BLAD) and complex vertebral malformation (CVM), play a major role in breeding of Holstein cattle. Both inherited diseases are based on single nucleotide polymorphisms that have been known for 12 and 7 yr, respectively. A total of 25,753 cattle were genotyped for BLAD (18,200 tests) and CVM (14,493 tests) in our laboratory since the beginning of the genotyping programs for these diseases. Based on founder effects, the CVM mutation is thought to be linked to milk production. The BLAD was genotyped using RFLP until 2001; then a fluorescence resonance energy transfer assay on a LightCycler was used, as for CVM genotyping. By using single nucleotide polymorphism-aided breeding, the allelic frequency of the BLAD and CVM mutations in the active sire population was reduced from 9.4% in 1997 to 0.3% in 2007 (BLAD) and from 8.3% in 2002 to 2.3% in 2007 (CVM), with calculated half-life of the mutant allele of 2.1 yr for BLAD and 3.6 yr for CVM. An observed increase of BLAD frequency in 1999 could be attributed to the massive use of a BLAD-positive sire tested falsely negative in another laboratory. These data show that marker-assisted selection is capable of substantially reducing the frequency of a mutation within a period of not more than 5 yr. The different selection strategies against the lethal recessive allele in CVM and BLAD are reflected in the different reduction rates of the specific allele frequencies.  相似文献   
66.
Many data warehouses contain massive amounts of data, accumulated over long periods of time. In some cases, it is necessary or desirable to either delete “old” data or to maintain the data at an aggregate level. This may be due to privacy concerns, in which case the data are aggregated to levels that ensure anonymity. Another reason is the desire to maintain a balance between the uses of data that change as the data age and the size of the data, thus avoiding overly large data warehouses. This paper presents effective techniques for data reduction that enable the gradual aggregation of detailed data as the data ages. With these techniques, data may be aggregated to higher levels as they age, enabling the maintenance of more compact, consolidated data and the compliance with privacy requirements. Special care is taken to avoid semantic problems in the aggregation process. The paper also describes the querying of the resulting data warehouses and an implementation strategy based on current database technology.  相似文献   
67.
针对全氟化合物这类新型的有机污染物,在环境中具有持久性,生物累积性和毒性的问题,以全氟辛酸为模型化合物,以真核生物酵母以及4基因缺失型酵母突变体和5基因缺失型酵母突变体为模式生物,开发便捷、灵敏的毒理学评价方法,探究全氟辛酸对不同基因缺失型酵母的毒性效应,以期建立以酵母为平台的环境污染物快速筛选系统.研究结果表明,5基因缺失型酵母突变体对全氟辛酸较为敏感,可以作为建立环境污染物快速筛选系统的细胞模型.  相似文献   
68.
We studied the processing of two word strings in French made up of a determiner and a noun which contains a schwa (mute e). Depending on the noun, schwa deletion is present, optional or absent. In a production study, we show that schwa deletion, and the category of the noun, have a large impact on the duration of the strings. We take this into account in two perception studies, which use word repetition and lexical decision, and which show that words in which the schwa has been deleted usually take longer to recognize than words that retain the schwa, but that this depends also on the category of the word. We explain these results by examining the influence of orthography. Based on the model proposed by Grainger and Ferrand (1996), which integrates the written dimension, we suggest that two sources of information, phonological and orthographic, interact during spoken word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
Glutaredoxin (Grx) is an important oxidoreductase to maintain the redox homoeostasis of cells. In our previous study, cold-adapted Grx from Psychrobacter sp. ANT206 (PsGrx) has been characterized. Here, we constructed an in-frame deletion mutant of psgrxpsgrx). Mutant Δpsgrx was more sensitive to low temperature, demonstrating that psgrx was conducive to the growth of ANT206. Mutant Δpsgrx also had more malondialdehyde (MDA) and protein carbonylation content, suggesting that PsGrx could play a part in the regulation of tolerance against low temperature. A yeast two-hybrid system was adopted to screen interacting proteins of 26 components. Furthermore, two target proteins, glutathione reductase (GR) and alkyl hydroperoxide reductase subunit C (AhpC), were regulated by PsGrx under low temperature, and the interactions were confirmed via bimolecular fluorescence complementation (BiFC) and co-immunoprecipitation (Co-IP). Moreover, PsGrx could enhance GR activity. trxR expression in Δpsgrx, Δahpc, and ANT206 were illustrated 3.7, 2.4, and 10-fold more than mutant Δpsgrx Δahpc, indicating that PsGrx might increase the expression of trxR by interacting with AhpC. In conclusion, PsGrx may participate in glutathione metabolism and ROS-scavenging by regulating GR and AhpC to protect the growth of ANT206. These findings preliminarily suggest the role of PsGrx in the regulation of oxidative stress, which could improve the low-temperature tolerance of ANT206.  相似文献   
70.
矩形件排样优化的最小余料删除法   总被引:1,自引:1,他引:0  
针对矩形件排样优化问题,分析了传统近似算法的主要缺陷,并在此基础上提出了一种新的排样算法———最小余料删除法.实验结果表明,同近似算法相比,最小余料删除法既满足实际生产的工艺要求,并能使板材利用率提高10%以上.  相似文献   
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