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41.
Summary Stylar proteins in 6 cultivars of Japanese pear (Pyrus serotina Rehd.) with different self-incompatibility alleles were examined by isoelectricfocusing polyacrylamide gel electrophoresis (IEF-PAGE). Cultivars used involved 1 self-compatible mutant Osa-Nijisseiki obtained from Nijisseiki (S2S4). Banding patterns of proteins were almost the same among the 6 cultivars except for 3 bands; one of which associated clearly with self-incompatibility S2-allele (hereafter the protein referred to as S2-protein) and was easily detectable because of its large amount and its pI value differed from many other proteins. Two other bands were seemingly associated with S3- and S4-alleles, respectively. The S2-protein was apparently present in the styles of Osa-Nijisseiki.The inheritance of S2-protein was studied by using 15 selfed plants of Osa-Nijisseiki. Eight out of 15 plants possessed the S2-protein as a major component of the stylar proteins and 3 plants as a minor component. The remainder 4 plants did not have the protein. This result may support that the S2-protein is the actual S2-gene product.Abbreviations IEF-PAGE isoelectrifocusing polyacrylamide gel electrophoresis - CBB Coomassie Brilliant Blue  相似文献   
42.
Anthocyanin synthesis began in the skin of ‘Olympia’ (Vitis labruscana Bailey) grape when the berry growth reached a late stage in the second sigmoid growth-curve. During berry development, shikimate NADP oxidoreductase (SORase, EC.1.1.1.25), phenylalanine ammonia-lyase (PAL, EC.4.3.1.5), and chalcone flavanone isomerase (CHFI, EC.5.5.1.6) were investigated in the skin. These enzyme activities were high during early development of the young berry, but rapidly decreased thereafter, and were activated again when rapid anthocyanin synthesis subsequently occurred. When PAL from the young berry was analyzed by isoelectricfocusing polyacrylamide gel electrophoresis (IEF-PAGE), it showed a single activity band with a pI value of approximately 5.4, whereas PAL from the ripe berry showed two activity bands with pIs of 5.4 and 6.5. Thus, SORase, PAL, and CHFI seem to be involved in anthocyanin accumulation simultaneously, and newly synthesized isozyme of PAL may play a key role in pigment formation in ‘Olympia’ skin. The function of these enzyme activities in young berry is also discussed in this text.  相似文献   
43.
In microorganisms, menaquinone is an obligatory component of the electron-transfer pathway. It is derived from chorismate by seven enzymes in Escherichia coli. However, a bioinformatic analysis of whole genome sequences has suggested that some microorganisms, including pathogenic species such as Helicobacter pylori and Campylobacter jejuni, do not have orthologs of the men genes, even though they synthesize menaquinone. We deduced the outline of this alternative pathway in a nonpathogenic strain of Streptomyces by bioinformatic screening, gene knockouts, shotgun cloning with isolated mutants, and in vitro studies with recombinant enzymes. As humans and commensal intestinal bacteria, including lactobacilli, lack this pathway, it represents an attractive target for the development of chemotherapeutics.  相似文献   
44.
Summary

We examined S-allele genotypes of ten apple cultivars and species to determine their possible usefulness as pollenizers for all apple cultivars. ‘Dolgo’ did not contain any known S-RNases encoded at the S-locus, suggesting its possible usefulness as a pollenizer for almost all apple cultivars. We also identified and confirmed the S-allele genotypes of 18 apple cultivars by polymerase chain reaction (PCR)-digestion analysis. The S-genotype of ‘Kiou’ (S1S7), ‘Korei’ (S3S28), ‘Korin’ (S1S9), ‘Kotoku’ (S1S28), ‘Kyokkou (S7S25), ‘Lobo’ (S1S7), ’Mahe 7’ (S2S7), ‘Mellow’ (S2S3), ‘Takahara’ (S3S9) and ‘Warabi’ (S9S28) were confirmed by pollination results. These cultivars seemed not to have originated from the expected seed or pollen parents or, in the case of ‘Lobo’, might have been mislabelled. Finally, we identified the S-allele genotypes of ‘Prima’ (S2S10), ‘Querina’ (S3S9) and ‘Yoko’ × ‘Prima’ (S3S10), which are resistant to scab.  相似文献   
45.
In an attempt to establish a primate model of chronic cadmium (Cd) toxicosis, we ovariectomized cynomolgus monkeys and treated with CdCl2 by repeated intravenous injections for 13 to 15 months. The animals showed an increase in blood glucose from Month 10 and a decrease in blood insulin at Month 11of the Cd-treatment. Histopathological examination of the Cd-treated animals revealed islet atrophy with reduction in islet number and vacuolation of the islet cells, whereas there was no remarkable change in the acinar cells of the exocrine pancreas. In histomorphometrical examination, insulin-positive areas in the islets were significantly decreased, accompanying a relative increase of glucagon-positive areas. Large amounts of Cd accumulated in the pancreas, and metallothionein (MT), a Cd binding protein, was localized in the islets of Cd-treated animals. The present study demonstrated that the chronic intravenous injection of Cd to cynomolgus monkeys induced the accumulation of the metal in the pancreas, degeneration of islet B cells and the diabetic clinical signs. Therefore the islet B cell is one of the major targets of the chronic Cd poisoning in monkeys.  相似文献   
46.
The polymerase chain reaction (PCR) is a rapid, precise method for detecting and identifying pathogenic bacteria. In addition to the published primers for identification of Agrobacterium tumefaciens up to species level, two sets of primers were designed to identify the nopaline and octopine types of Agrobacterium tumefaciens. The RBF-RBR primer set designed based on the nopaline type T-DNA right border detected the nopaline type A208 and R225f strains, and the ocsF-ocsR primer set derived from the ocs gene of the octopine type A. tumefaciens detected the octopine type A348 strain. After polymerase Chain reaction (PCR) amplification by the RBF-RBR primers, the A208 and R225f strains could be differentiated from each other by restriction fragment length polymorphism digestion using the restriction enzymes DraI and XbaI. Multiple colonies can be screened at one time in a single PCR tube with satisfactory efficiency, thereby allowing rapid detection of pathogenic A. tumefaciens. Following a rough screening by classical biovar medium and -methyl-d-glucoside medium, the developed PCR system was introduced to identify isolates collected from soil and crown gall samples. Of 42 isolates determined to be A. tumefaciens, 7 were found to be octopine type; all the rest were R225f type.  相似文献   
47.
48.
Hypothermia is directly linked to metabolism; however, it is still unknown how the overall metabolism is altered by oral administration of hypothermic agent, l -citrulline (l -Cit). The present study aimed to determine the characteristics of liver metabolites of chicks orally administered l -Cit to provide a greater understanding of its metabolism. Capillary electrophoresis–time-of-flight mass spectrometry (CE-TOFMS) and liquid chromatography–time-of-flight mass spectrometry (LC-TOFMS) were conducted on liver samples after oral administration of l -Cit. A total of 361 liver metabolites were identified. Although a small number of samples were used for each group, a principal component analysis and heatmap patterns confirmed that the composition of metabolites could be segregated from each other. Of the 361 compounds detected in the liver, 41 compounds, including amino acids related to the Cit-arginine (Arg) cycle, argininosuccinic acid, Arg, ornithine, and Cit, as well as gamma aminobutyric acid, glycine, histidine, and nicotinamide adenine dinucleotide were abundant in l -Cit-treated livers. In contrast, 24 compounds containing fatty acids, amino acids, and cyclic adenosine monophosphate were lower in the l -Cit group. These data imply that the active Cit-Arg cycle, TCA cycle metabolism, and a low activity in fatty acid metabolism occur in l -Cit-treated broiler chicks.  相似文献   
49.
Pedigree information is often missing for some animals in a breeding program. Unknown-parent groups (UPGs) are assigned to the missing parents to avoid biased genetic evaluations. Although the use of UPGs is well established for the pedigree model, it is unclear how UPGs are integrated into the inverse of the unified relationship matrix (H-inverse) required for single-step genomic best linear unbiased prediction. A generalization of the UPG model is the metafounder (MF) model. The objectives of this study were to derive 3 H-inverses and to compare genetic trends among models with UPG and MF H-inverses using a simulated purebred population. All inverses were derived using the joint density function of the random breeding values and genetic groups. The breeding values of genotyped animals (u2) were assumed to be adjusted for UPG effects (g) using matrix Q2 as u2=u2+Q2g before incorporating genomic information. The Quaas–Pollak-transformed (QP) H-inverse was derived using a joint density function of u2 and g updated with genomic information and assuming nonzero cov(u2,g). The modified QP (altered) H-inverse also assumes that the genomic information updates u2 and g, but cov(u2,g)=0. The UPG-encapsulated (EUPG) H-inverse assumed genomic information updates the distribution of u2. The EUPG H-inverse had the same structure as the MF H-inverse. Fifty percent of the genotyped females in the simulation had a missing dam, and missing parents were replaced with UPGs by generation. The simulation study indicated that u2 and g in models using the QP and altered H-inverses may be inseparable leading to potential biases in genetic trends. Models using the EUPG and MF H-inverses showed no genetic trend biases. These 2 H-inverses yielded the same genomic EBV (GEBV). The predictive ability and inflation of GEBVs from young genotyped animals were nearly identical among models using the QP, altered, EUPG, and MF H-inverses. Although the choice of H-inverse in real applications with enough data may not result in biased genetic trends, the EUPG and MF H-inverses are to be preferred because of theoretical justification and possibility to reduce biases.  相似文献   
50.
To evaluate the dielectric anisotropy caused by wood structure at a millimeter wave frequency of 100 GHz, the dielectric parameters for flat-sawn specimens of nine wood species at 0 and 11 % moisture content (MC) were measured using a free space method devised for reducing the multiple reflections under an electric field of millimeter waves parallel to longitudinal and tangential directions of wood, and those in radial direction were estimated using a conventional approximation theory. The dielectric parameters in the tangential and radial directions were almost identical and constantly smaller than those in the longitudinal direction. All the dielectric parameters increased with wood density and were larger at 11 than 0 % MC. The dielectric parameters in the longitudinal and transverse directions and the dielectric anisotropy between them were well fitted to the regression lines based on a dielectric mixture model composed of pores and dielectric isotropic wood substance, and a parallel capacitor and Lichtenecker’s exponential formulas were employed to represent the dielectric parameters of the mixture in the longitudinal and transverse directions, respectively. It was concluded that the dielectric anisotropy at 100 GHz is caused by the pore alignment and that the dielectric parameters are almost unaffected by anatomical structures, such as the rays. It was also confirmed that the free space method was effective for the measurement of the dielectric parameters for the flat-sawn specimens.  相似文献   
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