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101.
Phytochelatins (PCs) are post-translationally synthesized thiol reactive peptides that play important roles in detoxification
of heavy metal and metalloids in plants and other living organisms. The overall goal of this study is to develop transgenic
plants with increased tolerance for and accumulation of heavy metals and metalloids from soil by expressing an Arabidopsis
thaliana
AtPCS1 gene, encoding phytochelatin synthase (PCS), in Indian mustard (Brassica juncea L.). A FLAG-tagged AtPCS1 gDNA, under its native promoter, is expressed in Indian mustard, and transgenic pcs lines have been compared with wild-type
plants for tolerance to and accumulation of cadmium (Cd) and arsenic (As). Compared to wild type plants, transgenic plants
exhibit significantly higher tolerance to Cd and As. Shoots of Cd-treated pcs plants have significantly higher concentrations
of PCs and thiols than those of wild-type plants. Shoots of wild-type plants accumulated significantly more Cd than those
of transgenic plants, while accumulation of As in transgenic plants was similar to that in wild type plants. Although phytochelatin
synthase improves the ability of Indian mustard to tolerate higher levels of the heavy metal Cd and the metalloid As, it does
not increase the accumulation potential of these metals in the above ground tissues of Indian mustard plants. 相似文献
102.
103.
The apple, Malus × domestica Borkh, is one of the most important temperate fruit crops grown around the world. Although the apple is a diploid (2n = 34), it originated as an allopolyploid and has a relatively small genome size of 750 Mb/haploid. The apple is self-incompatible, highly heterozygous, and displays a juvenile period of 6 to 10 years or more. These characteristics contribute to long-term and difficult efforts to breed new cultivars of apple. However in the past 15 years, significant advances have been made to develop molecular markers linked to traits of economic interest for apple. In turn, these molecular markers have been used to map, clone, and isolate genes. Efforts to pursue map-based cloning in apple have been quite successful in identifying and characterizing target genes, particularly those controlling disease and pest resistance. Strategies of chromosome walking and chromosome landing have provided viable approaches to locate, isolate, and clone some of these genes. In this review, we provide detailed information for these strategies and their use to clone some of these target genes controlling qualitative traits. 相似文献
104.
Tatiana C Tatum Svetlana Stepanovic D P Biradar A Lane Rayburn Schuyler S Korban 《Génome》2005,48(5):924-930
The nuclear DNA content for a group of 40 Malus species and hybrids has been estimated using flow cytometry. Estimates of nuclear DNA content for this germplasm collection range from 1.45 pg for Malus fusca (diploid) to 2.57 pg for Malus ioensis (triploid). Among diploids, the nuclear (2C) DNA ranges from 1.45 pg for M. fusca to 1.68 pg for Malus transitoria. Among triploids, the nuclear (3C) DNA content ranges from 2.37 pg / 3C for Malus sikkimensis to 2.57 pg / 3C for M. ioensis. Given the complexity of the apple genome and its suggested allopolyploid origin, the results obtained in this study confirm earlier reports that polyploids can easily withstand the loss of a certain amount of DNA, and that there is a slight tendency towards diminished haploid nuclear DNA content with increased polyploidy. 相似文献
105.
106.
107.
Abdullah Alghasham Abdulaziz AM Al Salloom Ahmed SS Alghamadi 《Nucleosides, nucleotides & nucleic acids》2015,34(1):56-68
Present study probes the role of peroxynitrite (ONOO-)-modified thymidine-5′-monophosphate (TMP) in SLE patients with different disease activity scores according to the SLE Disease Activity Index (SLEDAI). Serum analysis showed significant increased number of subjects positive for anti-ONOO--TMP-protein antibodies in SLE patients with different SLEDAI scores. Interestingly, the levels of these antibodies were significantly higher among SLE patients, whose SLEDAI scores were ≥20. In addition, a significant correlation was observed between the levels of anti-ONOO--TMP-protein antibodies and the SLEDAI score (r = 0.595, p < 0.0001). In short, this study shows a positive association between anti-ONOO--TMP-protein antibodies and SLEDAI. The stronger response observed in patients with higher SLEDAI scores suggests that anti-ONOO--TMP-protein antibodies may be useful in evaluating the progression of SLE and in elucidating the mechanisms of disease pathogenesis. 相似文献
108.
Fernanda Fraga Campos Policarpo A Sales Junior Alvaro José Romanha Márcio SS Araújo Ezequias P Siqueira Jarbas M Resende Tania MA Alves Olindo A Martins-Filho Vera Lúcia dos Santos Carlos A Rosa Carlos L Zani Betania Barros Cota 《Memórias do Instituto Oswaldo Cruz》2015,110(1):65-74
Aiming to identify new sources of bioactive secondary metabolites, we isolated 82
endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia
echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro
assays. The organic extracts from three isolates showed antibacterial activity
against Staphylococcus aureus and Escherichia coli [minimal inhibitory concentration
(MIC) 32-64 μg/mL]. One isolate inhibited the growth of Salmonella typhimurium (MIC
64 μg/mL) and two isolates inhibited the growth of Klebsiella oxytoca (MIC 64 μg/mL),
Candida albicans and Candida tropicalis (MIC 64-128 μg/mL). Fourteen extracts at a
concentration of 20 μg/mL showed antitumour activities against human breast cancer
and human renal cancer cells, while two isolates showed anti-tumour activities
against human melanoma cancer cells. Six extracts were able to reduce the
proliferation of human peripheral blood mononuclear cells, indicating some degree of
selective toxicity. Four isolates were able to inhibit Leishmania (Leishmania)
amazonensis and one isolate inhibited Trypanosoma cruzi by at least 40% at 20 μg/mL.
The trypanocidal extract obtained from Fusarium sp. [] culture was subjected
to bioguided fractionation, which revealed beauvericin as the compound responsible
for the observed toxicity of Fusarium sp. to T. cruzi. This depsipeptide showed a
half maximal inhibitory concentration of 1.9 μg/mL (2.43 μM) in a T. cruzi cellular
culture assay. KF611679相似文献
109.
EG Ciolac SS Mantuani CM Neiva CEL Verardi DM Pess?a-Filho L Pimenta 《Biology of sport / Institute of Sport》2015,32(2):103-108
The aim of the present study was to analyse the usefulness of the 6-20 rating of perceived exertion (RPE) scale for prescribing and self-regulating high-intensity interval training (HIT) in young individuals. Eight healthy young subjects (age = 27.5±6.7 years) performed maximal graded exercise testing to determine their maximal and reserve heart rate (HR). Subjects then performed two HIT sessions (20 min on a treadmill) prescribed and regulated by their HR (HR: 1 min at 50% alternated with 1 min at 85% of reserve HR) or RPE (RPE: 1 minute at the 9-11 level [very light-fairly light] alternated with 1 minute at the 15-17 level [hard-very hard]) in random order. HR response and walking/running speed during the 20 min of exercise were compared between sessions. No significant difference between sessions was observed in HR during low- (HR: 135±15 bpm; RPE: 138±20 bpm) and high-intensity intervals (HR: 168±15 bpm; RPE: 170±18 bpm). Walking/running speed during low- (HR: 5.7±1.2 km · h−1; RPE: 5.7±1.3 km · h−1) and high-intensity intervals (HR: 7.8±1.9 km · h−1; RPE: 8.2±1.7 km · h−1) was also not different between sessions. No significant differences were observed in HR response and walking/running speed between HIT sessions prescribed and regulated by HR or RPE. This finding suggests that the 6-20 RPE scale may be a useful tool for prescribing and self-regulating HIT in young subjects. 相似文献
110.