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31.
为研究文昌鸡催乳素基因的分子生物学特性和就巢机理,提取文昌鸡全血总DNA,利用特异性引物PCR技术获得文昌鸡PRL基因,将其克隆至pGM-T载体上,并测序分析。结果表明,文昌鸡PRL基因与GenBank上已公布的白来航、泰和丝羽乌骨鸡核苷酸序列同源性分别为93.3%和93.5%,而氨基酸序列同源性均为89.6%;与其他动物PRL基因进行比较,发现亲缘关系越远,同源性越低。  相似文献   
32.
This study sought to investigate the possible inhibition mechanism of red rice polyphenols (RRP) on pancreatic α-amylase (PA) activity. RRP showed strong inhibition against PA activity and the half-inhibitory concentration (IC50) value was 3.61 μg/mL. The fluorescence quenching of PA by RRP was a combination of static quenching and dynamic quenching. RRP could aggregate with PA and the physiochemical properties of the aggregates were closely related to the concentration of RRP. Kinetic analysis suggested that the inhibition mode of RRP on PA was reversible inhibition, which was a mixing of competitive inhibition and noncompetitive inhibition. Molecular docking speculated that RRP could form hydrogen bonds with PA by binding to the catalytic active sites (ASP197, GLU233 and ASP300) and the microenvironments of TRP58 and TRP59 were altered, thus inhibiting PA activity.  相似文献   
33.
    
M. Fladung 《Plant Breeding》1993,111(3):242-245
The iaaL gene of Pseudomonas syringae subsp. savastanoi encodes an indoleacetic acid-lysine synthetase which conjugates free indoleacetic acid (IAA) with lysine. lAA-lys is biologically less active than free IAA. The iaaL coding region was expressed under the control of the cauliflower mosaic virus 35S promoter and transgenic potato plants were produced (Spena et al. 1991). 35S iaaL potato plants are characterized by increased internodal length and epinastic bending of older leaves. In three greenhouse experiments with plants grown in pots of different size and in two growth chamber experiments tuber number increased in iaaL transgenic plants compared to untransformed and vector-transformed controls of the same genotype. The increase in tuber numbers observed under controlled conditions was reflected in tuber yield which increased in the pot grown transgenics.  相似文献   
34.
35.
    
The objective of this study was to characterize the flavonoid compounds found in the different grain parts of common and tartary buckwheat, and to determine the contribution of these flavonoids to the antioxidant properties of buckwheat. Eight flavonoid compounds were quantified and their antioxidant activity determined by FRAP, DPPH, and ABTS assays. Of the flavonoid compounds identified rutin was the most abundant, particularly in tartary buckwheat, in which it comprised approximately 90% of total flavonoid content. Flavan-3-ols were detected in common but not tartary buckwheat, and quercetin was detected only in tartary buckwheat. Flavonoid content—in particular, levels of rutin, orientin, and/or epicatechin gallate—was found to influence the total antioxidant activity of buckwheat. Results from this study indicate that antioxidant activity is not only closely associated with flavonoid content, but that different flavonoids contribute differently to the total antioxidant activity of common and tartary buckwheat.  相似文献   
36.
    
The essential oils obtained by hydrodistillation from the aerial parts of Tunisian native Hypericum perfoliatum L. (sect. Drosocarpium Spach.) and Hypericum tomentosum (sect. Adenosepalum Spach.) were analyzed by GC and GC–MS. Thirty-two compounds were identified in the essential oils of H. perfoliatum with α-pinene (13.1%), allo-aromadendrene (11.4%), germacrene-D (10.6%), n-octane (7.3%), α-selinene (6.5%) and β-selinene (5.5%) as main constituents. Sixty-seven components were identified in the oil of H. tomentosum with menthone (17.0%), n-octane (9.9%), β-caryophyllene (5.3%), α-pinene (5.2%), lauric acid (4.1%) and β-pinene (3.7%) as the most abundant components. Both oils were characterized by the presence of many components which could have numerous applications in food, pharmaceutical and perfume industries.  相似文献   
37.
    
V. &#;ip    J. Chrpová    J. Vacke  J. Ovesná 《Plant Breeding》2004,123(1):24-29
The effects of the Yd2 gene on tolerance to barley yellow dwarf virus (BYDV) and other agronomically important characters in spring barley were evaluated in a set of randomly selected doubled haploid (DH) lines of an‘Igri’/‘Atlas 68’ cross and three crosses between CIMMYT Yd2 materials and the Czech malting barley ‘Akcent’. The cleaved amplified polymorphic site (CAPS) diagnostic marker Yd2 was used for identification of the Yd2 gene and this analysis showed high agreement with the results of field infection tests. Yd2 lines exhibited significantly lower symptom scores and lower reductions of some grain yield characters, but their resistance level was not consistent over the years. The presence of secondary stresses (high temperature/drought) in 2000 led to relatively higher sensitivity to BYDV infection, strengthened by the long life cycle of genotypes. In cases where secondary stresses were mild (in 2002), the longer life cycle significantly increased sensitivity to BYDV infection only in the absence of the Yd2 gene (in susceptible genotypes). The examination of different vegetative, grain yield and malting quality characters separately for groups of Yd2 and non‐ Yd2 lines did not show any evidence of adverse effect of the Yd2 gene on any character.  相似文献   
38.
    
This study aimed to investigate the application of microbubble technology for delaying banana ripening. A preparation of 1-MCP designed for use as a form of aqueous micro bubble (MBs) solutions was formulated. Banana fruit were immersed in 500 nL L−1 of aqueous 1-MCP microbubbles (1-MCP-MBs) or fumigated with 500 nL L−1 1-MCP, then stored at 25 °C for 8 days. 1-MCP-MBs were more effective in delaying postharvest ripening than conventional 1-MCP fumigation. 1-MCP-MBs reduced the respiration rate and ethylene production compared to the control and 1-MCP fumigated fruit. Moreover, 1-MCP-MBs delayed yellowing and maintained firmness of banana fruit during storage. These results indicate that 1-MCP-MBs can be used as an alternative method for delaying the postharvest ripening of banana fruit, and its application for other commodities needs to be further elucidated.  相似文献   
39.
对皇后黑李、隆丰1号黑李的生物学特征和植物学特性进行观察记载;开展皇后黑李优良单株的选育,选出优良单株——隆丰1号黑李。  相似文献   
40.
Three abortigenic Indian isolates of equine herpesvirus-1 (EHV-1) (Tohana, Hisar and Bikaner), along with two exotic abortigenic isolates (AB4 and V592) and another EHV-1 isolate (Jind) obtained from a case of perinatal foal mortality, were studied for variability. For this purpose, PCR and restriction endonuclease (RE) digestion techniques were used simultaneously as a DNA fingerprinting system. Nine different regions of EHV-1 virus were amplified by PCR using primer pairs specific for the regions and the products obtained from these regions were subsequently subjected to various restriction endonucleases to further assess the variability in the number of RE sites as well as in their positions. No difference was observed in all the four abortigenic isolates in terms of the size of different PCR products amplified by all the nine primer pairs, except for primer pairs ‘E’ and ‘C’. PCR products obtained with primer pair E revealed that Tohana and Bikaner isolates were most similar while Hisar isolate was like V592 isolate. However, the PCR product obtained from Jind isolate had a size between the PCR products of Hisar and Tohan/Bikaner isolates. The primer pair ‘C’ used to amplify the region between 1151 to 3679 in ‘Gene 1,2,3’ clearly differentiated the EHV-1 isolate obtained from a case of perinatal foal mortality from isolates obtained from abortion cases. This primer pair needs to be exploited more extensively for use as a potential marker for differentiating the EHV-1 isolates, mainly the abortion cases from perinatal foal mortality ones. Restriction endonuclease studies done with PCR product of all the isolates with various primer pairs did not reveal any changes in the position or number of RE sites present in the products amplified, indicating no variation in different RE sites within the amplified PCR products. However, this study clarified that all the Indian isolates belonged to the IP group of EHV-1.  相似文献   
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