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101.
In this study, prolactin gene polymorphism was investigated in Nili‐ Ravi buffaloes, Sahiwal and Achai cattle breeds, 100 per group, using polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) technique. Only genotype GG was observed in the case of Nili‐Ravi buffaloes. In Sahiwal and Achai cattle, three genotypes were found, AA, AG and GG: the frequency of these genotypes were 72%, 18% and 10% in Sahiwal cattle and 44%, 34% and 22% in Achai cattle, respectively. The frequency of genotype AA was found to be higher in both cattle breeds. Results of chi‐square test at P < 0.05 revealed that animals of Achai cattle were in Hardy–Weinberg equilibrium, whereas Sahiwal cattle were found to be deviating.  相似文献   
102.
The objective of this study was to identify allele and genotype frequencies of the κ‐CN and β‐LG genes in Anatolian water buffalo. A total of 126 water buffalos from Turkey were genotyped using the PCR‐RFLP method. For gene κ‐CN, only B allele and BB genotype were observed. And for gene β‐LG, two types of alleles (A and B) and three types of genotypes were observed. The genotype frequencies of AA, AB and BB of β‐LG in Anatolian water buffalo were 0.254, 0.698 and 0.048, respectively. Surprisingly, the frequency of allele A was higher than that of allele B in contrast to world buffalo breeds.  相似文献   
103.
The crystallization and melting behaviour of pure monoglyceride standards and two types of commercial monoglycerides were analyzed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Firstly, a series of saturated monoglycerides, ranging from monolaurin to monobehenin, were analyzed by DSC using a specific temperature program to obtain a complete image of the crystallization behaviour and polymorphism. The different crystallization and melting peaks were characterized by wide angle X-ray diffraction (WAXD) and small angle X-ray scattering (SAXS). Three polymorphic forms (sub-α, α and β) could be discerned for the shorter chain length saturated monoglycerides, while a second sub-α polymorph was observed for the longer chain length samples. Secondly, unsaturated monoglyceride standards were analyzed using the same methodology. These results reveal a less complex behaviour with the occurrence of only one polymorph. Finally, the analysis of two commercial monoglycerides revealed the importance of minor components for the crystallization of unsaturated monoglycerides.  相似文献   
104.
Zhou H  Hickford JG 《Meat science》2008,79(2):403-405
Calpastatin (CAST) specifically inhibits calpains and there is evidence that it plays a role in meat tenderization and myogenesis. Although the CAST gene has been extensively investigated in sheep and cattle, no studies have been reported in goats. In this study, a fragment of caprine CAST was analyzed using PCR–SSCP analysis. Seven novel SSCP patterns, representing seven different nucleotide sequences, were identified. All the sequences shared high homology with the published ovine and bovine CAST sequences. Sequence analysis revealed non-synonymous amino acid variation in exon 6, which would result in a Ser/Arg substitution in domain L of the protein. Considerable variation was detected in an intron region close to the acceptor splice site, with both sequence variation and length variation being observed in this region. Variation detected here might have an impact on both the function and expression of caprine CAST.  相似文献   
105.
There are little data in the literature on how to authenticate edible oils through calorimetry techniques. However, oil melting curves can be used to represent correlations between calorimetric results and oil quality. A calorimetric method has been developed for studying the solid–liquid phase transitions of olive oil and seed oils, in which melting peak behavior is correlated to the type, quality, and composition of the oil. Good reproducible thermograms were obtained by defining precise protocols for use in testing, which take into account the specific characteristics of a particular oil. This approach does not replace classical analytical methods; nevertheless, it is believed that calorimetric tests could be a useful preliminary stage for quality testing. The calorimetric technique allows the detection of the adulterant (seed oils or refined olive oil), oil origin, and possible photo-oxidation degradation processes, before more complex and expensive procedures and analyses are applied.  相似文献   
106.
The composition of secondary metabolites and the nutritional value of a plant both determine herbivore preference and performance. The genetically determined glucosinolate pattern of Barbarea vulgaris can be dominated by either glucobarbarin (BAR-type) or by gluconasturtiin (NAS-type). Because of the structural differences, these glucosinolates may have different effects on herbivores. We compared the two Barbarea chemotypes with regards to the preference and performance of two lepidopteran herbivores, using Mamestra brassicae as a generalist and Pieris rapae as a specialist. The generalist and specialist herbivores did not prefer either chemotype for oviposition. However, larvae of the generalist M. brassicae preferred to feed and performed best on NAS-type plants. On NAS-type plants, 100% of the M. brassicae larvae survived while growing exponentially, whereas on BAR-type plants, M. brassicae larvae showed little growth and a mortality of 37.5%. In contrast to M. brassicae, the larval preference and performance of the specialist P. rapae was unaffected by plant chemotype. Total levels of glucosinolates, water soluble sugars, and amino acids of B. vulgaris could not explain the poor preference and performance of M. brassicae on BAR-type plants. Our results suggest that difference in glucosinolate chemical structure is responsible for the differential effects of the B. vulgaris chemotypes on the generalist herbivore. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
107.
目的: 在中国汉族儿童中探讨白血病易感性与CYP3A5*3的频率之间的相关性。方法: 共收集172名中国汉族儿童血液,包括52名急性白血病患者(27女性,25男性)和120名健康儿童(53女性,67男性)。提取DNA,然后用PCR-RFLP方法检测基因型。结果: CYP3A5*3在人群中的分布符合Hardy-Weinberg 平衡。儿童白血病中CYP3A5*3频率为0.721(95% CI: 0.549, 0.893),而健康儿童中为0.758 (95% CI: 0.674, 0.842),两者之间无明显差异,并且也无男女性别差异。结论: CYP3A5*3是健康儿童和白血病患者中的常见基因型,健康儿童和白血病患儿中CYP3A5*3频率一致, 因此CYP3A5*3与儿童白血病易感性之间无关联。  相似文献   
108.
1,1‐Diamino‐2,2‐dinitroethene, C2H4N4O4 (FOX‐7), is a novel high energy density material with low friction and impact sensitivity and a high activation barrier to detonation. In this study, the previously unknown crystal structure of the γ‐polymorph of trimorphic FOX‐7 is reported. γ‐FOX‐7 is stable from ∼435 K until the compound decomposes just above 504 K. A single crystal of α‐FOX‐7 (P21/n, Z=4, a=694.67(7) pm, b=668.87(9) pm, c=1135.1(1) pm, β=90.14(1)°, T=373 K) was first transformed into a single crystal of β‐FOX‐7 (P212121, Z=4, a=698.6(1) pm, b=668.6(2) pm, c=1168.7(3) pm, T=423 K) and then into a single crystal of γ‐FOX‐7 at 450 K. The γ‐FOX‐7 crystal was then subsequently quenched to 200 K. The structure of γ‐FOX‐7 (P21/n, Z=8, a=1335.4(3) pm, b=689.5(1) pm, c=1205.0(2) pm, β=111.102(8)°, T=200 K) consists of four planar layers, each containing two crystallographically independent FOX‐7 molecules found in the asymmetric unit.  相似文献   
109.
There are 56 nationalities in China. Han is the largest and Zhuang the second largest. Geographically and linguistically, Zhuang can be classified into 43 ethnic subgroups, in which Hei Yi (meaning black‐worship and black‐dressing) Zhuang is proved to be the most conservative group according to its unique culture and custom. Information on the genetic influence on the lipid profile is limited in this population. To obtain some of this information, a cross‐sectional survey of hyperlipidemia was carried out in 500 people of Hei Yi Zhuang and 500 people of Han in the same area. The genotypes and alleles of the microsomal triacylglycerol transfer protein (MTP –493 G/T) were also determined, by polymerase chain reaction combined with an allele‐specific oligonucleotide hybridization method, and then confirmed by direct sequencing. The frequencies of the G and T alleles were 0.74 and 0.26, respectively, in Hei Yi Zhuang, and 0.73 and 0.27 (p >0.05) in Han. The frequencies of the GG, GT and TT genotypes were 0.58, 0.33 and 0.09, respectively, in Hei Yi Zhuang, and 0.56, 0.34 and 0.09 (p >0.05) in Han. In the combined population of both Hei Yi Zhuang and Han, the levels of total cholesterol, triacylglycerol, low‐density lipoprotein cholesterol, and apolipoprotein B in the TT genotype were significantly higher than those in the GT (p <0.05 to <0.01) or GG genotypes (p <0.05 to <0.01), but there were no significant differences in their values between the GG and GT genotypes (p >0.05). The levels of high‐density lipoprotein cholesterol and apolipoprotein A1 were not significantly different among the three genotypes (p >0.05).  相似文献   
110.
Luigi V. Mancini 《Software》1988,18(4):287-300
Since the introduction of Smalltalk, the object-oriented approach towards the organization of data and programs has become popular. In this paper the possibilities of exploiting procedure-oriented languages to allow an object-oriented style of programming are analysed. Although the two approaches are apparently dissimilar, a family of procedure-oriented languages is described which allows a high degree of freedom in programming and does not appear to restrain the programmer within the procedure-oriented scheme. Popular languages of this family are ML and PS-Algol. For such languages, a technique is developed which enables an efficient implementation of object-oriented features, such as the subclassing form of inheritance provided by Smalltalk-80 and Simula.  相似文献   
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