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111.

Background  

Immunosenescence is a process that affects all cell compartments of the immune system and the contribution of the immune system to healthy aging and longevity is still an open question. Lymphocyte subpopulations present different patterns of circadian variation and in the elderly alteration of circadian rhythmicity has been evidenced. The aim of our study was to analyze the dynamics of variation of specific cytotoxic lymphocyte subsets in old aged subjects.  相似文献   
112.
In the present paper we report on the effects of the insertion of the Agrobacterium rhizogenes rolC gene in the tomato (Solanum lycopersicum L., formerly Lycopersicon esculentum Mill.) cultivar Tondino. Several transgenic lines were successfully obtained, between which two clones, rolC1 and rolC3, were chosen for the analysis of morpho-productive traits as well as of the endogenous levels of auxin and abscisic acid. Consistent with the known phenotypic effect of this gene, the transformed tomato plants were significantly shorter than the corresponding controls. On the other hand, even if yield was not affected by the transformation in terms of average number of fruits produced, fruit weight was significantly lower in the transgenics with respect to the controls. Therefore, insertion of the rolC gene does not lead to an improvement in plant productivity.  相似文献   
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114.
Pre-samplings for sample size determination are strongly recommended to assure the reliability of collected data. However, there is a certain dearth of references about sample size determination in field experiments. Seldom if ever, differences in sample size were identified under different management conditions, plant traits, varieties grown and crop age. In order to analyze any differences in sample size for some of the variables measurable in rice field experiments, the visual jackknife method was applied to pre-samples collected in a paddy rice field in Northern Italy, where a management typical for European rice was conducted. Sample sizes for 14 variables describing plant features (plant density, spikelet sterility, biomass, carbon and nitrogen concentration for the different plant organs and for the whole plant) and for 12 variables describing physical and chemical soil features (texture, pH, water holding capacity, soil organic matter, total carbon and nitrogen concentration, mineral nitrogen concentration) and soil microbial activity were estimated. The elementary units of observation were a 3-plant sample and an aggregate sample of four 125 cm3 sub-samples respectively for plant- and soil-related variables. Sample sizes ranged between 15 and 27 for plant-related variables and between 5 and 6 for soil variables. Relating to plant features, remarkable differences in sample size were observed in carbon concentration values of different plant organs, probably due to maintenance respiration. Homogeneity among sample sizes for soil variables could be explained by the capability of aggregate samples in capturing a big part of the total variance. This study underlines importance of carrying out pre-samplings aiming at sample size determination for different variables describing the cropping system.  相似文献   
115.
A total of 1,366 Rhynchosporium secalis isolates causing scald on barley, rye, and wild barley (Hordeum spontaneum) were assayed for restriction fragment length polymorphism loci, DNA fingerprints, and mating type, to characterize global genetic structure. The isolates originated from 31 field populations on five continents. Hierarchical analysis revealed that more than 70% of the total genetic variation within regions was distributed within a barley field. At the global level, only 58% of the total genetic variation was distributed within fields, while 11% was distributed among fields within regions, and 31% was distributed among regions. A significant correlation was found between genetic and geographic distance. These findings suggest that gene flow is common at the local level while it is low between regions on the same continent, and rare between continents. Analyses of multilocus associations, genotype diversity, and mating type frequencies indicate that sexual recombination is occurring in most of the populations. We found the highest allele richness in Scandinavia followed by Switzerland. This suggests that R. secalis may not have originated at the center of origin of barley, the Fertile Crescent, nor in a secondary center of diversity of barley, Ethiopia.  相似文献   
116.
Random amplification of polymorphic DNA (RAPD-PCR) analysis was conducted on 48 isolates of Fusarium oxysporum f. sp. radicis-lycopersici (F.o.r.l.) from different geographic regions, representing all known vegetative compatibility groups (VCGs) except VCG 0097 and VCG 0099 and on eight isolates of F.oxysporum f. sp. lycopersici (F.o.l.), representing VCGs 0030, 0031, 0032 and 0033. Upon UPGMA (unweighted pair-group method with arithmetic averages) analysis of 86 RAPD-PCR markers generated by 16 informative primers and 44 markers obtained with eight microsatellite primers, a close relatedness was evident for F.o.r.l. isolates in VCGs 0090, 0092, 0096, and, to a lesser extent, for those in VCG 0093. Representatives of VCG 0091 formed a distinct group, while F.o.r.l. isolates in VCGs 0094 and 0098 were not distinguishable by the tested markers, most of which were also shared by F.o.l. isolates belonging to VCGs 0031 and 0033. F.o.l. isolates in VCGs 0030 and 0032 shared most of the molecular markers. The correlation between RAPD-PCR and microsatellite genetic distance was highly significant (R2 = 0.77; P by Mantel test < 0.001). The molecular variability observed in both formae speciales is discussed in relation to the development of F.o.r.l.- and F.o.l.-specific diagnostic tools.  相似文献   
117.
The rise and diversification of the dinosaurs in the Late Triassic, from 230 to 200 million years ago, is a classic example of an evolutionary radiation with supposed competitive replacement. A comparison of evolutionary rates and morphological disparity of basal dinosaurs and their chief "competitors," the crurotarsan archosaurs, shows that dinosaurs exhibited lower disparity and an indistinguishable rate of character evolution. The radiation of Triassic archosaurs as a whole is characterized by declining evolutionary rates and increasing disparity, suggesting a decoupling of character evolution from body plan variety. The results strongly suggest that historical contingency, rather than prolonged competition or general "superiority," was the primary factor in the rise of dinosaurs.  相似文献   
118.
ObjectiveTo evaluate staining of nerve branches after the injection of different volumes during ultrasound-guided transversus abdominis plane (TAP) block in dog cadavers.Study designProspective randomized study.AnimalsA total of 15 frozen/thawed adult dog cadavers.MethodsHemiabdomens were randomly allocated to one of four groups. In groups G0.3, G0.6 and G1.0, ropivacaine–methylene blue solution (0.3, 0.6 and 1.0 mL kg–1 in seven, eight and eight hemiabdomens, respectively) was injected at the midpoint between the iliac crest and the last rib at the height of the shoulder. In group G0.3×2 (seven hemiabdomens), two injections (0.3 mL kg–1) were performed, caudal to the last rib and cranial to the iliac crest at the same height. Total time for injection was recorded; after 30 minutes, cadavers were dissected and spread of dye was evaluated.ResultsAccuracy of injection site was 80% and injection time was 71 (48–120) seconds for all groups together. Craniocaudal spread was 6.4 ± 1.6, 9.1 ± 2.6, 11.4 ± 2.3 and 11.2 ± 3.8 cm for G0.3, G0.6, G1.0 and G0.3×2, respectively [G0.3 to G0.3×2 (p = 0.044) and G1.0 (p = 0.034)]. There was no difference in dorsoventral spread among groups. Number of ventral nerve branches stained was 3 (2–4), 3 (2–4), 3 (3–4) and 3 (2–4) for G0.3, G0.6, G1.0 and G0.3×2, respectively, including nerve branches from twelfth thoracic to third lumbar (L3) in different proportions among groups.Conclusions and clinical relevanceResults suggest that a single-injection TAP block, using 0.3 mL kg–1, stains comparable number of nerve branches as higher volumes or two-point injection. Despite the volume or technique, consistent staining of the innervation of the caudal abdomen (L1–L3) was observed. Additional cadaveric studies are necessary to identify the optimal technique for complete abdominal wall staining.  相似文献   
119.
All the main globulins in the seeds ofLupinus Albus are oligomeric glycoproteins. Legumins (33%) consist of two similar protein molecules which contain protomers linked by disulphide bridges. They result from a partial proteolytic breakdown of an original polypeptide chain. Vicilins (44%) consist of four similar protein molecules with several protomers linked together by non-covalent bonds. Globulin 1 (6%) has a native M.W. of 199 kd and is formed by four 45.0 kd subunits consisting of two smaller protomers (28.0 and 16.0 kd) linked by -S-S- bonds. Globulin 9b (12.5%) has the lowest M.W. (44.0 kd) and is made up of three protomers, two of which are linked by disulphide bonds.  相似文献   
120.
RadEst3.00 estimates and evaluates daily global solar radiation values at given latitudes. Radiation is calculated as the product of the atmospheric transmissivity of radiation times the radiation outside the earth atmosphere. Four models estimate the atmospheric transmissivity, based on the daily temperature range. Model parameters can be fitted over one or more years of data by iterative procedures. Graphical and statistical evaluations of the estimates are presented. Reports of the analysis can be exported in a variety of formats. Penman–Monteith or Priestley–Taylor reference evapotranspiration is estimated, using both measured and estimated radiation. Utilities are provided to process numerous files, or correct possible constant biases in the data. Samples of data for tropical and temperate sites are supplied with the software.  相似文献   
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