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61.
The effects of ammonia and hydrogen sulfide on the physical and biochemical properties of the claw horn of Holstein cows were evaluated. Significant (P < 0.05, 0.01) decreases in hardness and elasticity were found in claw horns soaked in ammonia (NH3) and hydrogen sulfide (H2S) solutions compared with those that were soaked in water for 12, 24, and 48 h. Water absorption rate, as a indicator of permeability barrier function, increased significantly (P < 0.05) over time during the soaking period and was found to be dependent on the concentrations of NH3 and H2S in the solutions. The contents of ceramide, the main lipid component for the permeability barrier system of the stratum corneum, were significantly decreased in claw horns soaked in NH3 and H2S solutions compared with the values before soaking. Quantities of eluted protein released from claw horns treated with NH3 and H2S solutions were approximately 20 times and 30 to 40 times greater than those released from claw horns treated with water alone. Interestingly, the quantities of cytokeratin 10, the main cytoskeletal protein of the stratum corneum, eluted from claw horns treated with NH3 and H2S solutions were markedly greater than the quantity released from horns soaked in water. Our results suggest that abnormal changes in the physical property of claw horn caused by NH3 and H2S treatment are due to disruption of the biochemical property of the claw horn induced by these chemical agents derived from slurry.  相似文献   
62.
63.
The mitochondrial pathway of apoptosis in vertebrates is dependent on the process of mitochondrial outer membrane permeabilization (MOMP), which leads to the release of proteins from the mitochondrial intermembrane space into the cytosol. "Upstairs" of this event are the Bcl-2 family proteins that regulate and mediate MOMP; "downstairs" is the activation of caspases that orchestrate the dismantling of the cell. In the Connections Map database at Science's Signal Transduction Knowledge Environment (STKE), the pathways that define the mitochondrial pathway of apotosis are illustrated, with the bulk of control occurring "upstairs" of MOMP.  相似文献   
64.

Context

While many woody perennials grow and reproduce in varying environments, their ability to modify their reproductive allocation under varying resource availability is unclear.

Aims

This study aimed to demonstrate the occurrence of plasticity of reproductive allocation in a pioneer woody species (Ulex europaeus).

Methods

We studied seed production in 144 plants under different irradiance and population densities. We measured their basal area, their whole shoot biomass and photosynthetic biomass, and their reproductive output (number of fruits per individual and number of seeds per fruit).

Results

We found that newly produced photosynthetic biomass was influenced by environmental variation, which in turn determined its reproductive output. In addition, in low light conditions investment in reproduction was more reduced than investment in growth indicating plasticity of reproductive allocation.

Conclusion

These results provide the first evidence for plasticity of reproductive allocation of a woody plant. It may lead to the ability of this pioneer species to survive and to continue to reproduce even at low rates in non-optimal shady habitats and to maintain a non-empty seed bank in forest systems with long unfavourable periods between two disturbances.  相似文献   
65.
Stay green or delayed senescence is considered to play a crucial role in grain development in wheat when assimilates are limited. We identified three QTLs for stay green on the chromosomes 1AS, 3BS and 7DS using a recombinant inbred (RI) population developed by making crosses between the stay green parent ‘Chirya 3’ and non-stay green ‘Sonalika’. The RI lines were evaluated in natural field conditions for 2 years in replicated trial. The QTL on chromosome 1A was identified in both the years, while the QTLs on 3BS and 7DS were identified only in 1st and 2nd year, respectively. The QTLs explained up to 38.7% of phenotypic variation in a final simultaneous fit. The alleles for higher stay green values derived from the stay green parent ‘Chirya 3’. The QTLs were named as QSg.bhu-1A, QSg.bhu-3B and QSg.bhu-7D. The QTL QSg.bhu-3B and QSg.bhu-7D were placed in the 3BS9-0.57-0.78 and 7DS5-0.36-0.61 deletion bins, respectively.  相似文献   
66.
The present study aimed at identifying single-nucleotide polymorphic (SNP) sites in different coding and non-coding regions of lactoferrin gene in Indian riverine buffaloes. A total of 102 animals from six different river buffalo breeds were screened at six bubaline lactoferrin gene loci. Single-strand conformation polymorphism (SSCP) analysis revealed monomorphic patterns at three loci LtfE2, LtfE11, and LtfE14 while a total of eight distinct patterns were observed in the other three loci viz. LtfE5, LtfE10, and LtfE16 which correspond to respective exons and their flanking regions. Sequence analysis of different SSCP variants revealed the presence of two SNP sites within the coding (exon 16) region and five SNP sites in flanking non-coding regions (intron 4 and intron 9). Both SNPs within exon 16 were found to be synonymous. The SNPs and haplotypes identified in the present study could serve as potential markers for association with susceptibility/resistance to mastitis in buffaloes.  相似文献   
67.
68.
We conducted hydroponic culture experiments to characterize root traits in a rice cultivar ‘Puluik Arang’ that has been identified in a previous study as a cultivar that is adaptable to unflooded conditions. Root morphological traits and the expression of 11 aquaporin genes in rice seedlings (cv. Puluik Arang and cv. Akitakomachi) subjected to osmotic stress by polyethylene glycol (PEG) treatments (10 and 20%) were analysed. ‘Puluik Arang’ exhibited significantly greater water uptake under 10% PEG treatment than ‘Akitakomachi’. Lateral root development was maintained in ‘Puluik Arang’ under PEG treatments. The expression of some aquaporin genes, particularly OsTIP2;1, was higher in ‘Puluik Arang’ than in ‘Akitakomachi’. Immunocytochemical analysis showed that the OsTIP2;1 protein mainly accumulated in endodermal cells. The results suggest that better lateral root development and the function of aquaporins could contribute to water uptake in ‘Puluik Arang’ under osmotic stress.  相似文献   
69.
In this study, buffalo (Bubalus bubalis) Toll-like receptor 8 (TLR8) gene has been characterized by sequence analysis and detecting polymorphism. Complete ORF of buffalo TLR8 gene was amplified using the RNA isolated from spleen tissue, which was found to be 3,102 nucleotides long encoding a 1,033 amino acid protein. Buffalo TLR8 had 10 nucleotide changes as compared to other livestock species resulting in six unique amino acid changes, four of them lying within leucine-rich repeat (LRR) domains. As compared to cattle (Bos indicus and Bos taurus), out of fifteen cysteine residues, fourteen were conserved and Cys at position 521 was replaced by Arg. Nine of the LRR domains had no amino acid change as compared to cattle, whereas LRR-C-terminus had maximum, five amino acid changes. Sequence characterization of 12 riverine and swamp buffaloes revealed presence of four polymorphic nucleotides, two of them were non-synonymous, one synonymous and one site in 3′UTR. PCR-RFLP genotyping of non-synonymous SNP 2758A>G (ILeu920Val) in Toll–interleukin-1 receptor domain of 463 swamp and riverine buffaloes showed a higher frequency of allele A in swamp (95 %) as compared to riverine (9.84 %) buffaloes.  相似文献   
70.
Syngnathidae is the family of fish that includes sea horses, pipefish, and sea dragons. To date, only a single publication has described neoplasia in syngnathids, a fibrosarcoma of the brood pouch in an aquarium-reared lined sea horse (Hippocampus erectus). From 1998 until 2010, the Toronto Zoo submitted 172 syngnathids for postmortem; species included the spotted or yellow sea horse (Hippocampus kuda), the pot-bellied sea horse (Hippocampus abdominalis) and the weedy sea dragon (Phyllopteryx taeniolatus). Seven neoplasms and two neoplastic-like lesions were identified from these cases. Under light microscopy, the neoplasms had morphological characteristics of a cardiac rhabdomyosarcoma, renal adenocarcinoma, renal adenoma, renal round cell tumors, which were likely lymphomas, exocrine pancreatic carcinoma, and intestinal carcinoma. Of these neoplasms, four had clear evidence of metastasis: the pancreatic and intestinal carcinomas and both round cell tumors. As syngnathids are highly fastidious animals, they can be difficult to maintain in captivity. In order to improve their husbandry, preventative and palliative care, as well as treatment, it is important to investigate and document the types of diseases affecting syngnathids.  相似文献   
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