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61.
62.
1. Many ectothermic species have evolved the ability to invoke a ‘behavioural fever’ when infected with a pathogen. The relative costs and benefits of this response, however, have rarely been quantified. 2. The aim of this study was investigate the nature and consequences of behavioural fever in the house fly, Musca domestica L., in response to infection with a possible biocontrol agent, the fungal entomopathogen, Beauveria bassiana (Balsamo) Vuillemin. 3. It was found that infected flies preferred higher temperatures and allocated more effort to thermoregulation than uninfected flies. Flies could not overcome infection but the altered thermal behaviour allowed infected flies to extend their survival and to lay more eggs relative to infected flies maintained under constant conditions. However, flies allowed to fever had lower egg viability suggesting a possible cost. 4. Under the present experimental conditions, the putative costs and benefits fever balanced one another resulting in no net change in fitness. Fever did not, therefore, limit the control potential of the fungus. We discuss whether the costs and benefits of behavioural fever might differ in other ecological contexts. 相似文献
63.
Effect of 1,2-benzisoxazole-3-acetic acid on adventitious shoot regeneration and in vitro rooting in apple 总被引:3,自引:0,他引:3
The effect of 1,2-benzisoxazole-3-acetic acid (BOA), compared to 1-naphthaleneacetic acid (NAA), on adventitious shoot formation
in leaf portions and compared to indolebutyric acid (IBA), on in vitro rooting in the apple (Malus domestica Borkh) cultivars McIntosh and Gala, and one rootstock, Jork 9, was investigated. BOA at 43.0 μm or 2.7 μm at NAA in combination
with 17.8 μm benzyladenine (BA), induced the highest number of explants to produce adventitious shoots in Jork 9. In Gala,
the combination of 21.5 μm BOA with 1.0 μm thidiazuron (TDZ) or with 22.0 μm BA induced the highest regeneration percentages,
58 and 54%, respectively, giving more satisfactory results than NAA (where only 42% of leaf explants exhibited shoot formation).
In McIntosh, the highest percentage of regeneration was obtained with 1.3 μm NAA and 22.0 μm BA, while 51% was the highest
response obtained with the BOA treatment. The combination of BOA with TDZ completely inhibited regeneration activity in leaf
portions of this cultivar. The shoots of all the genotypes obtained with the most morphogenetic NAA or BOA treatments were
excised, multiplied and successfully rooted and hardened. The results demonstrate that the synthetic auxin BOA is active in
inducing shoot regeneration from leaf explants of apple and that the activity of BOA in plant regeneration is genotype dependent.
When BOA was used to induce rooting in apple microcuttings, lower rooting percentages were obtained than with IBA, showing
that the effect of BOA in inducing root formation is very low and that it cannot be used routinely to replace IBA in the in
vitro rooting of microcuttings.
Received: 18 June 1998 / Revision received: 4 January 1999 / Accepted: 29 January 1999 相似文献
64.
Apple fruit acidity is genetically diversified by natural variations in three hierarchical epistatic genes: MdSAUR37, MdPP2CH and MdALMTII 下载免费PDF全文
Dongjie Jia Fei Shen Yi Wang Ting Wu Xuefeng Xu Xinzhong Zhang Zhenhai Han 《The Plant journal : for cell and molecular biology》2018,95(3):427-443
Many efforts have been made to map quantitative trait loci (QTL s) to facilitate practical marker‐assisted selection (MAS ) in plants. In the present study, using MapQTL and BSA‐seq (bulk segregant analysis using next generation sequencing) with two independent pedigree‐based populations, we identified four major genome‐wide QTL s responsible for apple fruit acidity. Candidate genes were screened in major QTL regions, and three functional gene markers, including a non‐synonymous A/G single‐nucleotide polymorphism (SNP ) in the coding region of MdPP 2CH , a 36‐bp insertion in the promoter of MdSAUR 37 and a previously reported SNP in MdALMTII , were validated to influence the malate content of apple fruits. In addition, MdPP 2CH inactivated three vacuolar H+‐ATP ases (MdVHA ‐A3, MdVHA ‐B2 and MdVHA ‐D2) and one aluminium‐activated malate transporter (MdALMTII ) via dephosphorylation and negatively influenced fruit malate accumulation. The dephosphotase activity of MdPP 2CH was suppressed by MdSAUR 37, which implied a higher hierarchy of genetic interaction. Therefore, the MdSAUR 37/MdPP 2CH /MdALMTII chain cascaded hierarchical epistatic genetic effects to precisely determine apple fruit malate content. An A/G SNP (?1010) on the MdMYB 44 promoter region from a major QTL (qtl08.1) was closely associated with fruit malate content. The predicted phenotype values (PPV s) were estimated using the tentative genotype values of the gene markers, and the PPV s were significantly correlated with the observed phenotype values. Our findings provide an insight into plant genome‐based selection in apples and will aid in conducting research to understand the fundamental physiological basis of quantitative genetics. 相似文献
65.
Identification and characterization of two novel C‐type lectins from the larvae of housefly,Musca domestica L. 下载免费PDF全文
Jing Zhou Nai‐ Nai Fang Ya Zheng Kai‐ Yu Liu Bin Mao Li‐ Na Kong Ya Chen Hui Ai 《Archives of insect biochemistry and physiology》2018,98(3)
Lectins and antimicrobial peptides (AMPs) are widely distributed in various insects and play crucial roles in primary host defense against pathogenic microorganisms. Two AMPs (cecropin and attacin) have been identified and characterized in the larvae of housefly. In this study, two novel C‐type lectins (CTLs) were obtained from Musca domestica, while their agglutinating and antiviral properties were evaluated. Real‐time PCR analysis showed that the mRNA levels of four immune genes (MdCTL1, MdCTL2, Cecropin, and Attacin) from M. domestica were significantly upregulated after injection with killed Gram‐negative Escherichia coli. Moreover, purified MdCTL1‐2 proteins can agglutinate E. coli and Staphylococcus aureus in the presence of calcium ions, suggesting their immune function is Ca2+ dependent. Sequence analysis indicated that typical WND and QPD motifs were found in the Ca2+‐binding site 2 of carbohydrate recognition domain from MdCTL1‐2, which was consistent with their agglutinating activities. Subsequently, antiviral experiments indicated that MdCTL1‐2 proteins could significantly reduce the infection rate of Spodoptera frugiperda 9 cells by the baculovirus Autographa californica multicapsid nucleopolyhedrovirus, indicating they might play important roles in insect innate immunity against microbial pathogens. In addition, MdCTL1‐2 proteins could effectively inhibit the replication of influenza H1N1 virus, which was similar to the effect of ribavirin. These results suggested that two novel CTLs could be considered a promising drug candidate for the treatment of influenza. Moreover, it is believed that the discovery of the CTLs with antiviral effects in M. domestica will improve our understanding of the molecular mechanism of insect immune response against viruses. 相似文献
66.
The response of fruiting or deblossomed trees to water stress such as drought or flooding was investigated in six semi open-top
cuvettes each containing one apple (Malus domestica Borkh. cv. Golden Delicious) tree. Xylem water potentials of leaves dropped from -1.2 to -4.1 MPa within 7 d of drought,
the effect being enhanced by fruiting. Apple trees without fruits showed smaller reductions in net photosynthetic rate (P
N
) and dark respiration rate (R
D
) after 2 d of drought and hence more positive carbon balances relative to fruiting trees. Flooding for 4 d had a more pronounced
effect on P
N
than on transpiration, resulting in a reduced water use efficiency (WUE). This reduction in WUE was greater in the non-fruiting
trees. Flooding reduced P
N
of the whole apple canopies irrespective of fruiting; aple trees without fruits increased R
D
resulting in a less positive carbon balance relative to fruiting trees. Fruiting increased the sensitivity to drought of
apple trees (R
D
and P
N
), but decreased their sensitivity to flooding (R
D
and WUE), suggesting different adaptation mechanisms for the two forms of water stress.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
67.
Xuetong Fan James P. Mattheis John K. Fellman Max E Patterson 《Physiologia plantarum》1997,101(2):328-332
Apple fruits ( Malus domestica Borkh.) were harvested from 24 to 136 days after full bloom (DAFB) and endogenous jasmonic acid was analyzed by GC-MS. There were two isomers of jasmonic acid in apple fruit with a ratio of 37:63 ( cis:trans ). The cis:trans ratio remained relatively constant throughout this period of fruit development. The endogenous jasmonic acid concentration was 138 ng g−1 fresh weight 24 DAFB and decreased as fruit developed. Changes in jasmonic acid concentration were coincident with those of respiration, ethylene production, and anthocyanin accumulation in patterns consistent with the reported responses to exogenous jasmonates. Possible roles for jasmonic acid during early fruit development are discussed. 相似文献
68.
Summary The ventral organs of the cephalic lobes of the house fly larvae, Musca domestica L., were studied by scanning and transmission electron microscopy. Four sensilla were found. Three of them are each innervated by a single dendrite whose ending possesses a tubular body and communicates to the exterior through an opening. These sensilla are assumed to be mechanoreceptors. The 4th sensillum is supplied by 2 bipolar neurons with the unbranched dendritic tips (without tubular bodies) exposed to the exterior through a single opening and is probably a contact chemoreceptor.This research was supported in part by the Office of Naval Research and NIH Training Grant ES-00069. Paper no. 3724 of the North Carolina State University Agricultural Experiment Station journal series. 相似文献
69.
New information is reported on the parasitism of Heterotylenchus autumnalis upon its principal known host, Musca autumnalis. Black to brown spots are produced on the cuticle of all infected host larvae where the nematode penetrated. The principal damage to the host is castration of the female. In laboratory tests nematode larvae were not infective and did not leave the hosts before the female fly was 1 1 days old. Nematode larvae removed from infected male flies infected other hosts, but it is believed that in nature these larvae are unable to leave the host. 相似文献
70.
【目的】探究香樟Cinnamomum caphora果实精油、天竺桂Cinnamomum pedunculatum叶精油和龙柏Sabina chinensis var.chinensis叶精油对家蝇Musca domestica成虫的熏蒸活性,比较这3种植物精油以及混配精油对家蝇的毒力效果,为植物源灭蝇剂的开发提供理论依据。【方法】利用水蒸汽蒸馏法提取植物精油,采取三角瓶密闭熏蒸法测试植物精油及其混剂对家蝇5日龄成虫的熏蒸毒性和击倒作用。【结果】3种植物精油对家蝇的LC50值(致死中浓)分别为5.28,16.86和14.54μg/cm3。LC90熏蒸剂量下,对家蝇的KT50值(击倒中时)分别为12.03,16.56和13.37 min。天竺桂叶精油和龙柏叶精油混配后对家蝇有增效作用,二者的LC50值配比为9∶1时,增效作用极为显著,共毒系数高达367.95。【结论】香樟果实精油对家蝇成虫有很好的熏杀和击倒作用,龙柏叶精油次之,天竺桂叶精油效果最差。天竺桂叶精油和龙柏叶精油混配后对其对家蝇成虫的熏蒸毒性有增效作用。3种植物精油具备开发环保灭蝇剂的潜力,可深入研究。 相似文献