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51.
Genetic Resources and Crop Evolution - Genomic Selection (GS) is a breeding technique that utilizes whole genome markers to make trait predictions. The goal of GS is to identify the top candidates...  相似文献   
52.
A total of sixty‐six germplasm lines were crossed with five CMS lines, where two belong to A4 cytoplasm, while other three belong to A2 cytoplasm. On the basis of pollen fertility test as well as good pod setting, of 330 hybrids, 34 restorer lines were observed in ICPA 2043 and 19 in ICPA 2092. Thirteen germplasm lines restored fertility in both the A4 CMS lines, viz. ICPA 2043 and ICPA 2092; however, none of the lines restored fertility in A2 CMS lines. For confirmation of result, restoration competence of identified lines tested subsequently 2 years at two different temperatures. The segregation patterns for fertility restoration studied in F2 and BC1F1 generations of selected ten crosses. Six crosses indicated the involvement of two major genes with recessive epistasis, three crosses confirmed dominant epistasis, and one cross indicated the involvement of duplicate recessive epistasis. The obtained results from this study will hasten the future three‐line breeding programme and lead the hybrid technology to the farmers' field with the better exploitation of CMS lines.  相似文献   
53.
The purpose of this study was to determine the plasma pharmacokinetics (PK) and toxicity of zebularine, an oral cytidine analog with demethylating activity, in dogs. Plasma zebularine concentrations were determined by HPLC‐MS/MS following an oral zebularine dose of 8 or 4 mg kg?1. Plasma zebularine clearance was constant. Mean maximum concentration (Cmax) was 23 ± 4.8 and 8.6 ± 1.4 µM following 8 and 4 mg kg?1, respectively. Mean half‐life was 5.7 ± 0.84 and 7.1 ± 2.1 following 8 and 4 mg kg?1, respectively. A single 8 mg kg?1 dose was well tolerated. Daily 4 mg kg?1 treatment in three laboratory dogs resulted in grade 4 neutropenia (n = 3), grade 1 anorexia (n = 2) and grade 1 or 2 dermatologic changes (n = 2). All adverse events resolved with supportive care. A 4 mg kg?1 dose every 21 days was well tolerated. A follow‐up dose escalation study is in progress with a lower starting dose.  相似文献   
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55.
Background: An oviduct-specific glycoprotein, OVGP1, is synthesized and secreted by non-ciliated epithelial cells of the mammalian oviduct which provides an essential milieu for reproductive functions. The present study reports the effects of recombinant buffalo OVGP1 that lacks post-translational modifications, and native Buffalo OVGP1 isolated from oviductal tissue, on frozen-thawed sperm functions and in vitro embryo development.Results: The proportion of viable sperms was greater(P 0.05) in the recombinant OVGP1-treated group compared to the native OVGP1-treated group at 2 h, 3 h, and 4 h of incubation. The proportion of motile sperms at3 h and 4 h of incubation; and membrane-intact sperms at 4 h was greater(P 0.05) in the native OVGP1-treated group compared to the control and recombinant OVGP1-treated groups. The proportion of capacitated and acrosome-reacted sperms was greater(P 0.05) in the native OVGP1-treated group compared to the recombinant OVGP1 group at 4 h. The rates of cleavage of embryos and their development to the blastocyst stage were greater(P 0.05) in the presence of either native or recombinant OVGP1 in comparison to control at 10 μg/mL concentration as compared to 5 or 20 μg/mL.Conclusions: The study suggests that both native and recombinant OVGP1 impart a positive effect on various sperm features and in vitro embryo development. However, native OVGP1 was found to have a more pronounced effect in comparison to recombinant non-glycosylated OVGP1 on various sperm functions except viability. Hence,our current findings infer that glycosylation of OVGP1 might be essential in sustaining the sperm functions but not the in vitro embryo development.  相似文献   
56.
Outbreaks of Peste des petits ruminants (PPR) viral disease in Black Bengal goats were investigated from the middle Indo-Gangetic Plains of India. Clinical profile of PPR-affected flocks was recorded from four different outbreak sites of the region. The PPR outbreak was diagnosed serologically using commercially available sandwich ELISA kit. Relatively, low mortality rate (mean 26.75%) for PPR outbreak was recorded due to the endemic status of the disease. To understand the role of oxidative stress in PPR virus pathogenesis, various oxidant and antioxidant parameters in goats infected with PPR were estimated and compared with the uninfected/healthy goats of the same flock. The measured high level of pro-oxidant malondialdehyde (MDA) obtained from lipid peroxidation along with lower levels of anti-oxidants viz. superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) in PPR-affected Black Bengal goats suggests oxidative stress as one of the mechanism of pathogenesis of PPR virus. In addition, the correlation of oxidative stress due to PPR and the resulting reproductive disorders in the female goats were evaluated. The abortion in pregnant does observed during PPR outbreak was proportional to debility and oxidative stress manifested during PPR infection. The reproductive performance of recovered female goats in the period of 18 months of monitoring was significantly compromised in terms of kidding and twinning frequency. The mortality rate in kids born from PPR-recovered goats was significantly higher compared to those from health goats in the first 9 months post-recovery. From the present study, it may be concluded that together with the PPR virus, infection in goats and the resulting oxidative stress play a vital role for abortion and reduced post-reproductive performance in Black Bengal female goat.  相似文献   
57.
The present study was planned to evaluate the role of vitamin E, if any, in attenuating the methomyl induced hematological and biochemical alterations in blood of male wistar rats. Animals, in the weight range of 130-150 g, were administered methomyl orally in drinking water at a sub-acute dose level of 4 mg/kg body weight on alternate days for a duration of one month, vitamin E was administered intraperitoneally to normal or methomyl treated rats on alternate days as a pretreatment for a week at a dose level of 50 mg/kg body weight and subsequently for a further period of one month. Methomyl treatment resulted in a significant increase in the levels of lipid peroxidation and super oxide dismutase (SOD) activity in erythrocytes. On the contrary, reduced Glutathione levels (GSH) and the activities of catalase, Glutathione-S-transferase (GST) and Glutathione peroxidase (GSHPx) were found to be significantly decreased. Methomyl treatment caused a significant increase in total leukocyte counts (TLC), platelet, neutrophil, eosinophil, and lymphocyte and monocyte counts. Scanning Electron Micrographs showed significant morphological changes, which included spherocytosis and poikilocytosis. However, vitamin E supplementation to methomyl treated rats significantly decreased the raised levels of LPO whereas it caused a significant increase in GSH levels. Also, vitamin E supplementation could significantly elevate the activities of catalase GSHPx, GST and resulted in the normalization of SOD activity. Vitamin E supplementation also proved to be effective in significantly decreasing the already raised values of TLC and lymphocytes counts and almost normalized the platelets, neutrophils, lymphocytes and monocytes counts. Further, vitamin E supplementation improved the morphology of the red blood cells. The study, therefore, concludes that vitamin E can effectively mitigate most of the adverse effects induced by methomyl in rat blood.  相似文献   
58.
Groundnut is an important food and oil crop in the semiarid tropics, contributing to household food consumption and cash income. In Asia and Africa, yields are low attributed to various production constraints. This review paper highlights advances in genetics, genomics and breeding to improve the productivity of groundnut. Genetic studies concerning inheritance, genetic variability and heritability, combining ability and trait correlations have provided a better understanding of the crop's genetics to develop appropriate breeding strategies for target traits. Several improved lines and sources of variability have been identified or developed for various economically important traits through conventional breeding. Significant advances have also been made in groundnut genomics including genome sequencing, marker development and genetic and trait mapping. These advances have led to a better understanding of the groundnut genome, discovery of genes/variants for traits of interest and integration of marker‐assisted breeding for selected traits. The integration of genomic tools into the breeding process accompanied with increased precision of yield trialing and phenotyping will increase the efficiency and enhance the genetic gain for release of improved groundnut varieties.  相似文献   
59.
Natural antioxidants applied as feed additives can improve not only animals’ health and overall performance but also increase their resistance to environmental stress such as heat stress, bad housing conditions, diseases, etc. Marine organisms, for example seaweeds – red, brown, and green macroalgae contain a plethora of biologically active substances, including phenolic compounds, polysaccharides, pigments, vitamins, micro- and macroelements, and proteins known for their antioxidant activity, which can help in the maintenance of appropriate redox status in animals and show pleiotropic effects for enhancing good health, and productivity. The dysregulated production of free radicals is a marked characteristic of several clinical conditions, and antioxidant machinery plays a pivotal role in scavenging the excessive free radicals, thereby preventing and treating infections in animals. Supplementation of seaweeds to animal diet can boost antioxidant activity, immunity, and the gut environment. Dietary supplementation of seaweeds can also enhance meat quality due to the deposition of marine-derived antioxidant components in muscles. The use of natural antioxidants in the meat industry is a practical approach to minimize or prevent lipid oxidation. However, overconsumption of seaweeds, especially brown macroalgae, should be avoided because of their high iodine content. An important point to consider when including seaweeds in animal feed is their variable composition which depends on the species, habitat, location, harvest time, growing conditions such as nutrient concentration in water, light intensity, temperature, etc. This review highlights the beneficial applications of seaweeds and their extracted compounds, which have antioxidant properties as feed additives and impact animal health and production.  相似文献   
60.
Heterogeneous inbred families segregating for rust resistance were identified from the two crosses involving susceptible (TAG 24 and TG 26) and resistant (GPBD 4) varieties of peanut. Rust‐resistant (less than score 5) and rust‐susceptible (more than score 5) plants were identified in each HIF and evaluated under rust epiphytotic conditions. The set of plants belonging to the same HIF, but differing significantly in rust resistance, not in other morphological and productivity traits, was regarded as near‐isogenic lines (NILs). Largely, rust‐resistant NILs had GPBD 4‐type allele, and susceptible NILs carried either TAG 24 or TG 26‐type allele at the three SSR loci (IPAHM103, GM1536 and GM2301) linked to a major genomic region governing rust resistance. Comparison of the remaining genomic regions between the NILs originating from each of the HIFs using transposon markers indicated a considerably high similarity of 86.4% and 83.1% in TAG 24 × GPPBD 4 and TG 26 × GPBD 4, respectively. These NILs are useful for fine mapping and expression analysis of rust resistance.  相似文献   
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