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21.
A vast majority of the world buffalo resource is concentrated in tropical and subtropical countries. Apart from heat stress and poor nutritional availability, endometritis is one of the most commonly encountered reproductive problems limiting fertility and consequently productive potential of the species. As demonstrated recently, endometritis impairs growth and follicular fluid composition of the largest follicle in buffalo. In the present study, the effect of endometritis on luteal development, function, nitric oxide (NO), and ascorbic acid was investigated. Reproductive tracts were collected from 90 cyclic buffaloes at an abattoir and grouped into endometritic (n?=?36) or non-endometritic (n?=?54) buffaloes based on physical examination of uterine mucus, white side test, and uterine cytology. Samples with pus-containing mucus, positive reaction on white side test, and/or >5 % neutrophils were considered to be positive for endometritis. Corpora lutea were enucleated, weighed, classified into stages I to IV, and assayed for progesterone (P4), NO, and ascorbic acid concentrations. Endometritic buffaloes had lesser (P?<?0.0001) luteal weight and P4, NO, and ascorbic acid concentrations than non-endometritic buffaloes. The findings indicated that endometritis impairs corpus luteum development and function in buffalo. Reduced luteal NO and ascorbic acid concentrations during endometritis are novel findings.  相似文献   
22.
Stripe rust of wheat caused by the fungal pathogen is a destructive foliar disease of wheat. Thus, it is crucial step to characterize the resistant germplasm for stripe rust in a diverse germplasm pool for their ultimate utilization in efficient crop rust resistance breeding. In the present study, we followed two pronged strategies involving integrated phenotypic and molecular characterization of 440 diverse wheat germplasm lines for rust resistance. The germplasm panel was extensively evaluated in field epiphytotic conditions during two consecutive years. After rigorous screening, 72 accessions were successfully revealed as resistant to moderately resistant to stripe rust. Subsequently, entries were then evaluated for their field agronomicperformances, considering prerequisites for serving as a donor germplasm,particularly for yield and 33 potential rust-resistant accessions were identified. Furthermore, to detect the sources of resistance, accessions were molecular characterized for potential race-specific resistance genes Yr5, Yr10,Yr15, and effective adult plant resistance (APR) gene Lr34/Yr18/pm38. We identified the 22 accessions possessing one or more single resistance genes and two accessions were observed with at least three of them. Moreover, Lr34/Yr18/pm38 was determined to confer resistance when observed along with any of the race-specific genes. Thus, the study not only provides proof of concept methodology to identify candidate resistant sources from large germplasm collections but simultaneouslyconfirmed the contribution of combining race-specific andnon-specific APR genes. The finding could further assist in the potential deployment of resistant genes directly into the stripe rust breeding program by involving marker-assisted approaches.  相似文献   
23.
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   
24.
The substance secreted by mussels, also known as nature’s glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs), a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA) and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs) that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review.  相似文献   
25.
From five paddy rice cultivars grown in Taiwan and harvested in the summers of 1997, 1998, and 1999, five calibrated models were established by backpropagation neural network program through different morphological and color features selection for classifying paddy rice harvested in the summer of 2000. With 60 features, the average classification rates of Model 1 and Model 5 were 92 and 99.8%, respectively. With the most effective 50 features, by loading in the first principal component, the average classification rate of Model 2 was 90.0%. With 35 features selected from the correlation coefficient matrix, the average classification rate of Model 3 was 91.0%. With the most effective 20 features of area, area/perimeter, 48th width, shape factor, maximum length/maximum width, average intensity of blue, maximum length, average intensity of green, 47th width, 50th width, average intensity of red, 1st width, 19th width, 5th width, 6th width, 29th width, perimeter, 46th width, 42nd width, and 4th width based on the contribution of the training model, the average classification rate of Model 4 was 91.8% and would be recommended for classifying five paddy rice cultivars of set trading prices because it required fewer features and held a stable classification rate.  相似文献   
26.
Gupta N  Sharma SK  Rana JC  Chauhan RS 《Fitoterapia》2012,83(6):1131-1137
In light of the economic importance of buckwheat as well as existence of enormous accessions of Fagopyrum species in the Himalayan regions of India, the characterization of tartary buckwheat for rutin content variation vis-à-vis DNA fingerprinting was undertaken so as to identify fingerprint profiles unique to high rutin content accessions. Rutin content analysis in mature seeds of 195 accessions of Fagopyrum tataricum showed a wide range of variation (6 μg/mg to 30 μg/mg D.W.) with most of the accessions (81%) containing 10-16 μg/mg of rutin followed by 14% accessions with significantly higher rutin content (17 μg/mg to 30 μg/mg) and 5% accessions with low rutin content (≤10 μg/mg). AFLP fingerprinting of 18 accessions having high (≥17 μg/mg) and low rutin content (≤10 μg/mg) with 19 EcoRI/MseI primer combinations yielded 136 polymorphic fragments out of total 907. The hierarchical and model-based cluster analyses of AFLP data strongly suggested that the 18 populations of F. tataricum were clustered into two separate groups. The high and low rutin content accessions were clustered into two separate groups based on AFLP fingerprinting. The AFLP fingerprints associated with high rutin content accessions of F. tataricum are expected to be useful for evaluation, conservation and genetic improvement of buckwheat.  相似文献   
27.
The action of the pyrethroid insecticide bioresmethrin on the corpus cardiacum (CC) has been studied in Locusta migratoria. Bioresmethrin increased the spontaneous electrical activity recorded from both the glandular and storage lobes, and induced repetitive discharge in these lobes in response to single electrical stimulation of the nervus corpus cardiacum II (NCC II) and NCC I, respectively. Incubation of the isolated CC in low concentrations of bioresmethrin (0.1-1.0 μmol) induced the release of bioassayable hyperlipaemic hormone. Injection of bioresmethrin into locusts was found to induce an elevation in the haemolymph lipid at a stage when there was no overt symptom of poisoning. It is concluded that bioresmethrin may act directly on the CC of locusts to modulate electrical activity and induce the release of hormones. The effects may precede overt symptoms of poisoning.  相似文献   
28.
Despite being targeted as a conservation flagship species for several decades, the tiger (Panthera tigris) grows ever more imperiled. Debate exists as to where tiger conservation should focus: on protected nature reserves or larger landscapes. We developed a landscape scale, density-based model to assess whether reasonably effective management of current reserves is adequate to ensure the survival of tiger populations. We focused on the Indian subcontinent, the region likely to harbor most tigers. Using tiger density estimates and vegetation data, we set tiger population targets that could be attained through reasonable management of the subcontinent’s nature reserves. Depending on the quality of the surrounding landscape matrix, our model indicated that the subcontinent could potentially hold ∼3500-6500 tigers, in up to 150 reserves. Strikingly, just 21 reserves can hold most (58-95%) of this tiger capacity. These high-population target reserves were relatively insensitive to the hostility of the surrounding matrix to tigers, as their aggregate capacity varied by <10% across a wide range of matrix conditions. In contrast, the remaining 129 reserves were highly sensitive to matrix quality, as they were unable to sustain populations with a tiger-hostile matrix, even with reasonable management. Our results suggest that reasonably improved management of the subcontinent’s reserves can sustain multiple tiger populations based on two differing conservation strategies. Conservation within the 21 reserves with the largest population targets should focus primarily on the reserves themselves. In contrast, tiger conservation in the remaining reserves can succeed only with additional management of the unprotected landscapes that surround them.  相似文献   
29.
The enzymatic conjugation of arginine to the N-termini of proteins is a part of the ubiquitin-dependent N-end rule pathway of protein degradation. In mammals, three N-terminal residues-aspartate, glutamate, and cysteine-are substrates for arginylation. The mouse ATE1 gene encodes a family of Arg-tRNA-protein transferases (R-transferases) that mediate N-terminal arginylation. We constructed ATE1-lacking mouse strains and found that ATE1-/- embryos die with defects in heart development and in angiogenic remodeling of the early vascular plexus. Through biochemical analyses, we show that N-terminal cysteine, in contrast to N-terminal aspartate and glutamate, is oxidized before its arginylation by R-transferase, suggesting that the arginylation branch of the N-end rule pathway functions as an oxygen sensor.  相似文献   
30.
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