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1.
The objective of this study was to analyse the effects of different levels of rumen-degradable protein (RDP) on intake, digestibility and microbial protein synthesis by supplementing mustard oil cake (MOC) on rice straw-based diet of cattle (Bos indicus) in Bangladesh. A 4 × 4 Latin square design was applied. Four diets having constant energy (7.0 MJ/kg of dry matter (DM)) with varying levels of RDP (M 0 = 4.1 g/MJ (control), M 1 = 6.3 g/MJ, M 2 = 8.3 g/MJ and M 3 = 12.4 g/MJ of metabolizable energy (ME)) were received by each animal for a period of 28 days. A metabolism trial was conducted for 7 days. Results indicate that with increasing levels of RDP, crude protein (CP) and RDP intake increased significantly (P < 0.01). The significant (P < 0.01) increase in digestibility values are obtained for DM, organic matter, CP and digestible organic matter in the rumen. The digestibility of neutral detergent fibre and acid detergent fibre was also increased significantly (P < 0.05). The total nitrogen (N), ammonia-N and total volatile fatty acids increase significantly (P < 0.01) while the rumen pH increased from M 0 to M 2 and decreased thereafter. The efficiency microbial N intake increased significantly (P < 0.01) but showed a curvilinear response with higher RDP level (12.40 g/RDP/MJ ME). This study concludes that supplementation of RDP from MOC enhances the intake, digestibility and microbial protein synthesis which ultimately increases utilization of low-quality feed resources that can be used for developing cost-effective feeding systems on a straw-based diet in tropical regions.  相似文献   
2.
MytiLec; a novel lectin isolated from the Mediterranean mussel (Mytilus galloprovincialis); shows strong binding affinity to globotriose (Gb3: Galα1-4Galβ1-4Glc). MytiLec revealed β-trefoil folding as also found in the ricin B-subunit type (R-type) lectin family, although the amino acid sequences were quite different. Classification of R-type lectin family members therefore needs to be based on conformation as well as on primary structure. MytiLec specifically killed Burkitt''s lymphoma Ramos cells, which express Gb3. Fluorescein-labeling assay revealed that MytiLec was incorporated inside the cells. MytiLec treatment of Ramos cells resulted in activation of both classical MAPK/ extracellular signal-regulated kinase and extracellular signal-regulated kinase (MEK-ERK) and stress-activated (p38 kinase and JNK) Mitogen-activated protein kinases (MAPK) pathways. In the cells, MytiLec treatment triggered expression of tumor necrosis factor (TNF)-α (a ligand of death receptor-dependent apoptosis) and activation of mitochondria-controlling caspase-9 (initiator caspase) and caspase-3 (activator caspase). Experiments using the specific MEK inhibitor U0126 showed that MytiLec-induced phosphorylation of the MEK-ERK pathway up-regulated expression of the cyclin-dependent kinase inhibitor p21, leading to cell cycle arrest and TNF-α production. Activation of caspase-3 by MytiLec appeared to be regulated by multiple different pathways. Our findings, taken together, indicate that the novel R-type lectin MytiLec initiates programmed cell death of Burkitt’s lymphoma cells through multiple pathways (MAPK cascade, death receptor signaling; caspase activation) based on interaction of the lectin with Gb3-containing glycosphingolipid-enriched microdomains on the cell surface.  相似文献   
3.
ABSTRACT

Production from small scale pond aquaculture in Bangladesh trebled in the decade to 1999 under the influence of extension projects of the Department of Fisheries. The impacts of completed aquaculture extension projects and practices of former participants have rarely been investigated so this was done for four past projects. The different extension approaches were: extension with credit and intensive or little supervision; demonstrations; group extension and informal extension by fry traders; and adaptive research-development. Generally extension recipients and non-participants had similar sized landholdings, but demonstration farmers had larger farms and ponds. Extension recipients mainly received information from project-related sources and rated its utility highly. Neighbours and control farmers mainly obtained information from mass media and other farmers, over 90% of these households also cultivated fish. Extension recipients generally followed better practices: for example stocking fewer fingerlings and achieving higher production than non-participants, but with wide variations. Training of fry traders appeared to reduce overstocking in general probably due to the advice of fry traders. Overall, 2–6 years after extension the recipients have continued to farm fish, have a fair understanding of good practice and achieve reasonable yields. Limited demonstration effects occurred. Extension through group approaches and informal agents seem to be cost effective for the many pond owners in Bangladesh.  相似文献   
4.
Pigeonpea is an important food legume crop of semi‐arid tropical regions. Plateauing of pigeonpea yield has been worrying breeders for the past 6–7 decades. Serious breeding efforts made during this period resulted in various high‐yielding and disease resistant cultivars. However, the gains in pigeonpea productivity have been modest. The authors, while reviewing this situation, conclude that long generation turnover, complexity of biological traits, low selection response and overreliance upon pedigree breeding present the key bottlenecks for this situation. In this paper, some alternative breeding approaches and technologies are suggested for the genetic enhancement of yield stability and stress response of pigeonpea.  相似文献   
5.
Reproductive stage frost poses a major constraint for wheat production in countries such as Australia.However,little progress has been made in identifying key genes to overcome the constraint.In the present study,a severe frost event hit two large-scale field trials consisting of six doubled haploid(DH)wheat populations at reproductive stage(young microspore stage)in Western Australia,leading to the identification of 30 robust frost QTL on 17 chromosomes.The major 18 QTL with the phenotype variation over 9.5%were located on 13 chromosomes including 2 A,2 B,2 D,3 A,4 A,4 B,4 D,5 A,5 D,6 D,7 A,7 B and7 D.Most frost QTL were closely linked to the QTL of anthesis,maturity,Zadok stages as well as linked to anthesis related genes.Out of those,six QTL were repetitively detected on the homologous regions on 2 B,4 B,4 D,5 A,5 D,7 A in more than two populations.Results showed that the frost damage is associated with alleles of Vrn-A1 a,Vrn-D1 a,Rht-B1 b,Rht-D1 b,and the high copy number of Ppd-B1.However,anthesis QTL and anthesis related genes of Vrn-B1 a and Ta FT3-1 B on chromosomes 5 B and 1 B did not lead to frost damage,indicating that these early-flowering phenotype related genes are compatible with frost tolerance and thus can be utilised in breeding.Our results also indicate that wild-type alleles Rht-B1 a and Rht-D1 a can be used when breeding for frost-tolerant varieties without delaying flowering time.  相似文献   
6.
Fusarium wilt is an important disease of pigeonpea [Cajanus cajan (L.) Millsp.] and it can cause severe yield losses. Chemical control of this disease is difficult and expensive; therefore, cultivation of resistant varieties/hybrids is the most efficient strategy for enhancing the production. In the present study, by using a wilt susceptible cytoplasmic-nuclear male-sterile line and four wilt resistant fertility restorers, one dominant and one recessive gene with dominant suppressive epistatic effects were found responsible for controlling resistance to Fusarium wilt. Considering the annual losses and wide spread nature of wilt diseases in pigeonpea, it is imperative that all the inbred and hybrid cultivars have high level of resistance to this disease. The presence of dominant gene for resistance will increase the efficiency of breeding wilt resistant cultivars because it will yield greater proportion of resistant genotypes in segregating generations. In hybrid breeding also, the presence of dominant gene for wilt resistance will be an advantage. The transfer of this gene in female hybrid parents will ease the breeding of wilt resistant hybrids because this will allow the use of both wilt resistant as well as susceptible restorers in generating wilt resistant hybrid combinations.  相似文献   
7.
Genetically modified corn has been approved as an animal feed in several countries, but information about the fate of genetically modified DNA and protein in vivo is insufficient. Genetically modified corn Bt11 is developed by inserting a recombinant DNA sequence encoding insecticidal Cry1Ab protein from Bacillus thuringiensis subsp. kurstaki. We examined the presence of corn intrinsic and recombinant cry1Ab gene by PCR, and the Cry1Ab protein by immunological tests in the gastrointestinal contents of five genetically modified corn Bt11-fed and five nongenetically modified corn-fed pigs. Fragments of corn zein (242 bp), invertase (226 bp) and of ribulose-1,5-bisphosphate carboxylase/ oxygenase genes (1,028 bp) were detected in the gastrointestinal contents of both Bt11 and nongenetically modified corn-fed pigs. Fragments of recombinant cry1Ab gene (110 bp and 437 bp) were detected in the gastrointestinal contents of the Bt11-fed pigs but not in the control pigs. Neither corn intrinsic nor cry1Ab gene fragments were detected in the peripheral blood by PCR. The gastrointestinal contents were positive for Cry1Ab protein by ELISA, immunochromatography, and immunoblot; however, these methods did not work for blood and precluded conclusions about any potential absorption of the protein. These results suggest that ingested corn DNA and Cry1Ab protein were not totally degraded in the gastrointestinal tract, as shown by their presence in a form detectable by PCR or immunological tests.  相似文献   
8.
The isothiocyanate (ITC) yield of wasabi, the Japanese horseradish (Wasabi japonica), was measured on its release from glucosinolates in the rhizomes of plants grown in two traditional ways. Mature plants of 18 months old were harvested from two different commercial farms located in the South Island of New Zealand. At one farm, the plants were grown in raised soil beds, while the plants at the other farm were grown in gravel irrigated by river water. Following harvest, the rhizomes from each growth medium were divided into five size groups based on the weight and length of the rhizomes. The different sized rhizomes were also subdivided into proximal, medial, and distal portions of the rhizomes and each portion was further subdivided into epidermis plus cortex, and vascular plus pith. The individual and total ITC contents of each portion (proximal, medial, and distal) of the rhizomes were measured using dichloromethane extraction followed by the GC-FPD. The total ITC content of the rhizomes grown in soil increased (13 times) linearly from 6 to 114 g of rhizome weight, while the mean ITC content of the water-grown wasabi increased (10 times) nonlinearly for similar sized rhizomes. Water-grown rhizomes in the weight range from 18 to 45 g gave significantly (P = 0.030) higher total ITC (1-2 times) than similarly sized soil-grown rhizomes. Analysis of the tissues showed that the total and the individual ITCs were found in significantly higher levels (73 and 64%, respectively) in the skin and cortex tissue compared to the vascular and pith tissues. Analysis of the ITC content of the different locations of the wasabi rhizome showed that the distal portion of the rhizome contained significantly higher levels of both total and individual ITCs compared to the medial and proximal portions of the rhizome.  相似文献   
9.
The study investigated the potential effect of the microbial fermented feed utilization on physicochemical traits, antioxidant enzyme and trace mineral analysis in rabbit meat. A total of 72 six-week-old male rabbits were weighed and randomly divided into four groups (1) (SRKC) control; (2) (SRKP) Lactobacillus plantarum 1 × 106 cfu/g fresh weight (FW); (3) (SRKG) Pediococcus acidilactici 1 × 106cfu/g FW and (4) (SRKPG) P. acidilactici + L. plantarum 1 × 106 cfu/g FW. Performance characteristic, weekly body weight, was positively (p < .05) enhanced, while daily feed intake (DFI) and feed convention ratio (FCR) were not influenced in treatments group as compared to untreated. The water, protein, water holding capacity (WHC) and dry matter (DM) concentration were positively (p < .05) influenced, while ash, pH, lightness, redness and yellowness were not influenced in treated group as compared to untreated. The concentration of glutathione peroxidase (Gpx), superoxide dismutase (SOD) and aspartate aminotransferase (AST) was positively (p < .05) influenced in treatments group as compared to control. Regarding trace minerals, copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) were positively (p > .05) reduced in treated group as compared to untreated. It is concluded that the addition of lactic acid bacteria (L. plantarum and P. acidilactici) in Hybrid pennisetum silage had a constructive influence on rabbit health performance and meat biochemistry.  相似文献   
10.
Current study investigated the fermentative production of cell mass and crude protein using an axenic culture of the thermotolerant strain of Chlorella vulgaris grown mixotrophically in an illuminated 10-l glass bioreactor. The process was then upscaled to 1,000-l bioreactor. The organism supported maximum specific growth rate, crude protein volumetric productivity, and specific productivity of 1.2?day?1, 2.26?g?l?1?day?1, and 0.76?g?g?1?day?1, respectively, with urea as nitrogen source. Gibbs free energy, enthalpy, and entropy values for its formation were 74.3, 56. 2?kJ?mol?1, and ?59.1?J?mol?1?K?1, respectively, in both reactors and corresponded to those of thermotolerant organisms. Algal biomass grown in 10-l bioreactor contained 0.52?±?0.03, 12.6?±?2.0, 60.0?±?4.5, 0.4?±?0.02, 4.5?±?0.2, 12?±?0.5, and 3.81?±?0.5% carotenoids, carbohydrates, crude protein, DNA, RNA, lipids, and total chlorophyll, respectively. Dry biomass supported good growth of fish larvae comparable with that on commercial diet.  相似文献   
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