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81.
m‐carboxycinnamic acid bishydroxamide improves developmental competence,reduces apoptosis and alters epigenetic status and gene expression pattern in cloned buffalo (Bubalus bubalis) embryos 下载免费PDF全文
H Agrawal NL Selokar M Saini MK Singh MS Chauhan P Palta SK Singla RS Manik 《Reproduction in domestic animals》2018,53(4):986-996
Incomplete or aberrant reprogramming of nuclear genome is one of the major problems in somatic cell nuclear transfer. In this study, we studied the effect of histone deacetylase inhibitor m‐carboxycinnamic acid bishydroxamide (CBHA) on in vitro development of buffalo embryos produced by Hand‐made cloning. Cloned embryos were treated with CBHA (0, 5, 10, 20 or 50 μM) for 10 hr from the start of reconstruction till activation. At 10 μM, but not at other concentrations examined, CBHA increased (p < .05) the blastocyst rate (63.77 ± 3.97% vs 48.63 ± 3.55%) and reduced (p < .05) the apoptotic index of the cloned blastocysts (8.91 ± 1.94 vs 4.36 ± 1.08) compared to untreated controls, to levels similar to those in IVF blastocysts (4.78 ± 0.74). CBHA treatment, at all the concentrations examined, increased (p < .05) the global level of H3K9ac in cloned blastocysts than in untreated controls to that observed in IVF blastocysts. Treatment with CBHA (10 μM) decreased (p < .05) the global level of H3K27me3 in cloned blastocysts than in untreated controls but it was still higher (p < .05) than in IVF blastocysts. CBHA (10 μM) treatment increased (p < .05) the relative expression level of pluripotency‐related genes OCT‐4 and NANOG, and anti‐apoptotic gene BCL‐XL, and decreased (p < .05) that of pro‐apoptotic gene BAX than in untreated controls but did not affect the relative expression level of apoptosis‐related genes p53 and CASPASE3 and epigenetics‐related genes DNMT1, DNMT3a and HDAC1. These results suggest that treatment of cloned embryos with 10 μM CBHA improves the blastocyst rate, reduces the level of apoptosis and alters the epigenetic status and gene expression pattern. 相似文献
82.
Relationship between endometritis and oxidative stress in the follicular fluid and luteal function in the buffalo 下载免费PDF全文
BK Behera CG Sharma SK Singh H Kumar RK Chaudhari AS Mahla GK Das N Krishnaswamy 《Reproduction in domestic animals》2016,51(5):844-847
In this study, alteration in the follicular fluid composition and luteal function was investigated in the buffalo with endometritis. Genitalia were classified into cytological and purulent endometritis on the basis of polymorphonuclear cell cut off while non‐endometritis served as control (n = 10/group). In the follicular phase, the number of surface follicles was counted, diameter of the largest follicle was measured and the follicular fluid was assayed for total protein, cholesterol, malondialdehyde (MDA), total antioxidant capacity (TAC), oestradiol (E2) and progesterone (P4). The P4 content of corpus luteum during mid‐luteal phase was estimated by radioimmunoassay. Ovaries from the follicular phase of oestrous cycle showed no significant difference in the total number of surface follicles, size of the largest follicle and volume of follicular fluid in the buffaloes with and without endometritis (p > .05). However, the antral fluid of the largest follicle from the genitalia of buffalo with cytological and purulent endometritis showed a significant decrease in the concentration of total protein, cholesterol, TAC and E2 and a significant increase in the concentration of MDA and P4 (p < .05). The results indicated that there is an association between endometritis and decreased ovarian function. 相似文献
83.
Irenie Chakoma Lovemore C Gwiriri Godfrey Manyawu Sikhalazo Dube Mercy Shumba Aleck Gora 《African Journal of Range and Forage Science》2016,33(3):181-184
The major challenge to adoption of improved forage technologies in the smallholder farming sector is poor accessibility to seed of improved cultivars. Since 2012, the Zimbabwe Crop Livestock Integration for Improved Food Security (ZimCLIFS) project set out to address such challenges through research-for-development initiatives. The main objective was to demonstrate the potential viability of a pasture seed business using a lead farmer approach, farmer-to-farmer technology dissemination, innovation platforms and field demonstrations. Snapshot surveys were used to map forage seed distribution pathways within and outside project areas. Total land area planted to forages from the 2012/13 to 2014/15 seasons increased by 147% from 14.6 ha. In 2013, Mucuna pruriens (mucuna), Lablab purpureus (lablab) and Vigna unguiculata (cowpea) seed produced was 2 250 kg, 120 kg and 4 450 kg, respectively, and by the third season, total yield increased by 163%. Seed diffusion was within and beyond project boundaries, with mucuna (67%) and lablab (43%) seed produced in the 2013/14 season being distributed outside the project area. Highest amounts received by some farmers were US$800 and US$750 for lablab and mucuna, respectively. It was concluded that there is scope to develop formal pasture seed businesses to increase rural industrialisation and provide a pathway out of poverty in the smallholder sector. 相似文献
84.
Godfrey Manyawu Irenie Chakoma Siboniso Moyo Sikhalazo Dube 《African Journal of Range and Forage Science》2016,33(4):247-251
The objective of this on-farm study was to develop an effective and labour-extensive method to cure forage Lablab purpureus ‘Highworth’ for resource-constrained smallholder farmers in the Goromonzi district, Zimbabwe in 2014. In a completely randomised factorial design, the drying rate of forage subjected to three conditioning treatments, viz. pressing with a plain water-filled 200 L steel drum, pressing with a water-filled 200 L steel drum covered with 14-gauge wire mesh, and chopping to 5?cm length with a machete, was compared with that of unconditioned forage. The conditioning treatments were subjected to three natural aeration methods, viz. Aframe, raised platform, and dry ground. Replicated four times, conditioned forage was cured at a swath density of 25?kg m?2 to cover 3?m2?per treatment over 28 d. Conditioning of forage had a significant (p < 0.05) effect on drying rate. However, conditioning did not have a significant (p > 0.05) effect on crude protein content. Aeration treatments did not have a significant effect (p > 0.05) on drying rate or crude protein content. Moisture loss rate was higher for forage conditioned with a wired drum and machete. Conditioning with a machete was most labour intensive compared with drum conditioning treatments. Laceration and pressing is an effective and labour-extensive conditioning method for resource-constrained smallholder farmers. 相似文献
85.
Peer Saba Manzoor Kiran Dube Rawat Virendra Kumar Tiwari Nalini Poojary Babitha Rani Asanaru Majeedkutty 《Aquaculture Research》2020,51(8):3244-3254
An experiment was conducted for 120 days to evaluate optimum dietary lipid requirements for gonadal maturation of Cyprinus carpio fed with varying dietary lipid levels under biofloc‐based systems (BFT). About 180 fingerlings (22 g ± 0.05) were randomly distributed in 15 tanks (300 L) at the rate of 48 no./m2 and fed with varying lipid levels (T1—4% lipid with BFT, T2—6% lipid with BFT, T3—8% lipid with BFT, T4—10% lipid with BFT, control—10% lipid without BFT). The C/N ratio of 20:1 was maintained using tapioca flour as carbon source. Biofloc units supplemented with 8% dietary lipid (T3) showed advanced maturation in terms of absolute fecundity (9,913 ± 7.62), relative fecundity (229.0/g ± 11.92), gonadosomatic index (24.47% ± 1.27), hepatosomatic index (1.97% ± 0.07), condition factor (0.02 g/cm3 ± 0.00) compared with control (clear water with 10% lipid) (p < .05). Histological observations of gonads also revealed that the biofloc groups with supplementation of 8% dietary lipid promoted gonadal maturation for female oocyte and 6% dietary lipid promoted maturation for males, compared with control (clear water with 10% lipid). The results obtained in this experiment elucidate that the biofloc improves gonadal maturation of common carp broodstock at a dietary supplementation with 8% lipid compared with conventional system of broodstock management. 相似文献
86.
Conventional and contemporary approaches for drought tolerance rice breeding: Progress and prospects
C Anilkumar Rameswar Prasad Sah Radha Beena Muhammed Azharudheen TP Awadesh Kumar Sasmita Behera NC Sunitha SK Pradhan KR Reshmi Raj Parameswaran C BC Marndi Anil Kumar Singh 《Plant Breeding》2023,142(4):418-438
Drought is becoming a major threat to rice farming across the globe owing to the depletion of water tables in rice-growing belts. Drought affects rice plants at multiple stages, causing damage at morphological and physio-biochemical levels, leading to severe losses that exceed losses from all other stresses. The amalgamation of conventional breeding methods with modern molecular biology tools and biometrical methods could help accelerate the genetic gain for drought tolerance in rice. Many drought-tolerance traits with genetic determinants have been identified and exploited for tolerance rice variety breeding. The integration of genome-wide association study and genomic selection tools with speed breeding shortened the breeding cycle and aided in rapid improvement of genetic gain. In this review, we emphasized the progress made through classical breeding as well as the limitations and usefulness of current genomic methods in improving drought tolerance. We briefly addressed methods for identifying genetic determinants for drought tolerance and deploying them through genomics-assisted breeding programmes to develop high-yielding drought-tolerant rice cultivars. 相似文献
87.
Genetic diversity in 90 Indian soybean cultivars was assessed using 45 SSR markers distributed on 20 soybean chromosomes. Forty-five SSR markers generated 232 alleles with an average of five alleles/locus. The observed frequencies of the 232 alleles ranged from 0.01 to 0.94 with an average of 0.19. The polymorphic information content (PIC) value of the SSR markers varied from 0.10 to 0.83 with an average of 0.61 and about 71% markers have a PIC value of >0.5. In this study, 54 rare alleles including 19 genotype specific alleles were also identified. The observed hetrozygosity for SSR markers ranged from 0 to 0.11 with a mean of 0.10. Cluster analysis grouped the 90 soybean cultivars into three major clusters and principal coordinates analysis (PCoA) results were similar to those of the cluster analysis. A combination of eight SSR markers successfully differentiated all 90 soybean cultivars. The population structure analysis distributed the 90 soybean genotypes into two populations with mean alpha (α) value of 0.1873. In AMOVA analysis, proportion of variation within population was high (88%), whereas only 12% occurred among populations. In cluster and structure analyses, most of the genotypes with similar pedigree were grouped together. Soybean cultivars DS228, MACS-13, LSb-1, Hardee, Improved Pelican, and Pusa-24 were the six most genetically distinct cultivars identified. The study reported a moderate genetic diversity in Indian soybean cultivars and findings would be useful to the soybean breeders in selecting genetically distinct parents for a soybean improvement program. 相似文献
88.
Francis Dube Miguel Espinosa Neal B. Stolpe Erick Zagal Naresh V. Thevathasan Andrew M. Gordon 《Agroforestry Systems》2012,86(2):113-128
No information is available about carbon (C) sequestration potentials in ecosystems on Andisols of the Chilean Patagonia. This study was undertaken to measure the size of C stocks in three predominant ecosystems: Pinus ponderosa-based silvopastoral systems (SPS), pine plantations (PPP) and natural pasture (PST), and examine how clover affect tree growth and stocks of soil C. The C contents of trees and pasture were determined by destructive sampling and dry combustion. Soil samples were taken at 0?C5, 5?C20, 20?C40?cm depths in order to determine soil C and N. For PPP and SPS total aboveground tree C was 38.4 and 53.1?kg tree?1 and belowground was 21.3 and 23.4?kg tree?1, respectively. Annual diameter increment at breast height was 1 and 2?cm in PPP and SPS, respectively, and was significantly higher in SPS. Trees in SPS, due to lower density and the presence of leguminous pasture, demonstrated enhanced growth and C sequestration. Soil organic C (SOC) stocks at 0?C40?cm depth were 193.76, 177.10 and 149.25?Mg?ha?1 in SPS, PST and PPP, respectively. The conversion of PPP to SPS and PST to PPP resulted in an increase of 44.51?Mg?ha?1 and a decrease of 27.85?Mg?ha?1 in SOC, respectively. Favorable microclimatic conditions in relation to air temperature and soil moisture were observed in SPS as well as a synergy between trees and pasture. 相似文献
89.
V. Sandhya Ali SK. Z. Minakshi Grover Gopal Reddy B. Venkateswarlu 《Biology and Fertility of Soils》2009,46(1):17-26
Production of exopolysaccharides (EPS) can be used as a criteria for the isolation of stress tolerant microorganisms. In the
present study, EPS-producing fluorescent pseudomonads were isolated from alfisols, vertisols, inseptisols, oxisols, and aridisols
of different semiarid millet growing regions of India and were screened in vitro for drought tolerance in trypticase soy broth
supplemented with different concentrations of polyethylene glycol (PEG6000). Out of the total 81 isolates, 26 could tolerate
maximum level of stress (−0.73 MPa) and were monitored for the amount of EPS produced under maximum level of water stress.
The strain GAP-P45, isolated from alfisol of sunflower rhizosphere, showed the highest level of EPS production under water
stress conditions, was identified as Pseudomonas putida on the basis of 16S rDNA sequence analysis, and was used as seed treatment to study its effect in alleviating drought stress
effects in sunflower seedlings. Inoculation of Pseudomonas sp. strain GAP-P45 increased the survival, plant biomass, and root adhering soil/root tissue ratio of sunflower seedlings
subjected to drought stress. The inoculated bacteria could efficiently colonize the root adhering soil and rhizoplane and
increase the percentage of stable soil aggregates. Scanning electron microscope studies showed the formation of biofilm of
inoculated bacteria on the root surface and this, along with a better soil structure, might have protected the plants from
the water stress. 相似文献
90.
Z.P. Dube P.W. Mashela A.H. Abdelgadir 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(5):479-482
Moringa oleifera plants are highly nutritious and had since attracted much attention for serving as alternative crops in marginal communities in developing countries. Generally, claims abound that moringa plants are pest-free, with ISO precluding the use of unregistered products. However, moringa seedlings are often attacked by an unidentified aggressive spider mite (Tetranychus species) under humid greenhouse conditions, resulting in outright withering of seedlings, with the potential of decimating an entire moringa orchard. Thus, molecular techniques were used to identify the spider mites on moringa to the species level in order to allow for the development of management strategies. Spider mite strains from moringa and adjacent sweet stem sorghum (Sorghum bicolor) seedlings were collected and mitochondrial cytochrome c oxidase subunit I (COI) gene used for molecular identification. DNA sequences were generated and subjected to Blastn search on the National Center for Biotechnology Information database, with the neighbour-joining method used to establish the relative closeness of the test strains to Tetranychus species. Phylogenetically, the test spider mite was, Tetranychus urticae, closely related to T. urticae strains in Lineage I, which is dominated by the Mediterranean haplotypes. The derived information would allow for the development of appropriate management strategies of this pest on moringa seedlings using various products for eventual registration. 相似文献