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Green-gram (Phaseolus aureus) plants were treated with petro-cokedust, a paniculate pollutant of petroleum refineries, at therate of 2 g petro-coke m–2 d–1 for 40 consecutivedays between 26 and 65 d of plant age. Plant samples collectedfrom control and dusted plots were analysed with respect totranspiration rate, mineral accumulation, and contents of ascorbicacid, protein, carbohydrate, and pigments. Morphological parameters,phytomass accumulation, net primary productivity, and calorificvalues were also determined. On petro-coke treatment, transpiration rates increased at firstbut were lower in the 65 d old plants than in control plants.Accumulation of N, P, S, K, and Ca was less in treated plantsthan in the control plants at all ages. Ascorbic acid, protein,and carbohydrate contents were reduced in treated plants. Totalchlorophyll initially increased in treated plants but lateron decreased at higher cumulative doses of petro-coke. Rootand shoot lengths, number of leaves, nodules, flowers, and podswere reduced in petro-coke-treated plants.  相似文献   
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Characteristics of Transport of L-Leucine and Glycine in Pea Protoplasts   总被引:1,自引:0,他引:1  
The uptake of L-leucine and glycine into pea protoplasts wasstudied under various conditions. The uptake of both L-leucineand glycine was pH dependent with the optimal pH being 4.0 and5.0 for L-leucine and glycine, respectively. A kinetic studyof L-leucine uptake showed that uptake is multiphasic; Km valuesof different phases were 1.1 mol m–3, 33.3 mol m–3and 100 mol m3. A similar analysis for glycine at a concentrationrange of 0.1–10 mol m–3 also showed a multiphasictransport system for it. The uptake of L-leucine at lower concentrations(between0.1–2.0 mol m–3) was energy dependent, since arsenate,azide, dinitrophenol and iodoacetate inhibited the uptake. However,the uptake of L-leucine was not inhibited by ouabain at anyconcentration of L-leucine employed. The uptake of glycine wasnot inhibited by any of these inhibitors suggesting that glycineuptake was not mediated by an active process. Key words: Pea protoplast, L-Leucine, Glycine transport, Active transport, Mediated transport  相似文献   
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The outgrowth of lateral buds is known to be controlled by theupper shoot tissues, which include the apex, the young leavesand the upper stem. An analysis of the influence of these plantparts on axillary bud elongation in Ipomoea nil was carriedout by various treatments on these specific tissues. A restriction of elongation in the main shoot due to eitherdecapitation or shoot inversion resulted in the release of apicaldominance A non-linear type of compensating growth relationshipwas observed between the 13 cm apical growing region of thestem and the lateral buds. It was determined by decapitation,defoliation and AgNO3 treatments that both the 13 cm stem-growthregion and the young leaves (1–5 cm in length) had a muchgreater inhibitory influence on the outgrowth of specified lateralbuds than did the stem apex (consisting of the terminal 0.5cm of the shoot). The specified lateral buds which were analyzedfor outgrowth were located a number of nodes below the shootapex. The intervening nodes were debudded. Although the importanceof young leaves in the control of apical dominance has beenpreviously recognized, the most significant result from thepresent study with Ipomoea was the strong influence of the 13cm apical growth region of the stem on the out growth of thelateral buds. Apical dominance, Ipomoea nil L., Pharbitis nil, growth region, lateral bud outgrowth, decapitation, defoliation, shoot inversion  相似文献   
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ADAM33, a member of the ADAM (a disintegrin and metalloprotease) gene family, is an asthma susceptibility gene originally identified by positional cloning. In the present study, we investigated the possible association of five single-nucleotide polymorphisms (SNPs) in the ADAM33 (rs511898, rs528557, rs44707, rs597980 and rs2787094) with adult-onset asthma in an Indian population. The study included 175 patients with mild intermittent (n = 44), mild persistent (n = 108) or moderate persistent (n = 23) subgroups of asthma, and 253 nonasthmatic control individuals. SNPs were genotyped with the help of restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR) method, and data were analysed using chi-square test and logistic regression model. Bonferroni’s correction for multiple comparisons was applied for each hypothesis. Genotypes and allele frequencies of SNPs rs511898 and rs528557 were significantly associated with adult-onset asthma (P = 0.010-<0.001). A significant association of the homozygous mutant genotype and mutant alleles of SNPs rs2787094, rs44707 and rs597980 with the asthma was also observed (P = 0.020-<0.001). A positive association between asthma and haplotypes AGCCT, GGCCT, AGACT, GCAGT, GGACT, ACCCC and AGACC were also found (P = 0.036-<0.001, OR = 2.07–8.49). Haplotypes AGCGT, GCAGC, ACAGC, ACAGT, GGAGC and GGCGT appear to protect against asthma (P = 0.013-<0.0001, OR = 0.34–0.10). Our data suggest that ADAM33 gene polymorphisms serve as genetic risk factors for asthma in Indian adult population.  相似文献   
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We quantified abscisic acid and a cytokinin trans zeatin ribosideas potential positive or negative signals in root to shoot communicationin sunflower plants (Helianthus annuus L.) growing in dryingsoil. Delivery rates rather than concentration values were usedbecause the former are less subject to change as a result ofdifferences in sap flow through dilution. ABA concentrationand delivery rate increased under the mild drought stress. Incontrast, t-ZR concentration did not change under mild stressalthough delivery rates decreased significantly. With more severedrought stress, both delivery rates and concentration of t-ZRdecreased considerably while ABA concentration and deliverywere enhanced markedly. Root ABA contents mirrored those ofxylem ABA. Helianthus annuus ; soil drying; root signals; ABA; cytokinins; delivery rate; delivery rate  相似文献   
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Abstract: Identification of wildlife species from indirect evidence can be an important part of wildlife management, and conventional methods can be expensive or have high error rates. We used chemical characterization of the volatile organic constituents (VOCs) in scat as a method to identify 5 species of North American canids from multiple individuals. We sampled vapors of scats in the headspace over a sample using solid-phase microextraction and determined VOC content using gas chromatography with a flame ionization detector. We used linear discriminant analysis to develop models for differentiating species with bootstrapping to estimate accuracy. Our method correctly classified 82.4% (bootstrapped 95% CI = 68.8–93.8%) of scat samples. Red fox (Vulpes vulpes) scat was most frequently misclassified (25.0% of scats misclassified); red fox was also the most common destination for misclassified samples. Our findings are the first reported identification of animal species using VOCs in vapor emissions from scat and suggest that identification of wildlife species may be plausible through chemical characterization of vapor emissions of scat. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):792–797; 2008)  相似文献   
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