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The future of the endangered red panda (Ailurusfulgens) depends in part on the development of protective measures against infectious diseases. The present study is a first step toward improved understanding of infectious diseases in the species' home regions. Serum samples obtained from 73 red pandas in 10 captive facilities in southwest, east, and northeast China from October to December 2004 were tested for antibodies against nine common infectious pathogens of carnivores. Antibody titers against canine distemper virus (CDV), canine parvovirus (CPV), and canine adenovirus (CAV) in the three facilities in which red pandas were vaccinated were highly variable. The CAV titer in one vaccinated red panda was high enough to suggest infection with the field virus following vaccination. Together with anecdotal reports of vaccine-associated morbidity and mortality, our results suggest that the Chinese vaccine is not suitable for this species. In the seven unvaccinated groups, CDV titers were low and occurred in 20-100% of the animals; antibody titers against CPV were found in seven of eight areas. Only one of 61 and two of 61 unvaccinated red pandas had CAV and canine coronavirus titers, respectively, and these titers were all low. Positive titers to Toxoplasma gondii were found in four locations (33-94% seropositive); the titers in 52% of seropositive individuals were of a magnitude consistent with active disease in other species (1:1,024 to > or = 1:4,096). One red panda in each of three locations was seropositive for Neospora caninum. Antibodies against canine herpesvirus and Brucella canis were not detected in any of the samples. Only one of the 73 red pandas had a weak positive influenza A titer. The results of this study emphasize the need for research on and protection against infectious diseases of red pandas and other endangered species in China.  相似文献   
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Conservation strategies for the giant panda (Ailuropoda melanoleuca) include the development of a self-sustaining ex situ population. This study examined the potential significance of infectious pathogens in giant pandas ex situ. Serologic antibody titers against canine distemper virus (CDV), canine parvovirus (CPV), canine adenovirus (CAV), canine coronavirus (CCV), canine herpesvirus, canine parainfluenza virus (CPIV), Toxoplasma gondii, Neospora caninum, and Leptospira interrogans were measured in 44 samples taken from 19 giant pandas between 1998 and 2003 at the Chengdu Research Base of Giant Panda Breeding in Sichuan, China. Seroassays also included samples obtained in 2003 from eight red pandas (Ailurus fulgens) housed at the same institution. All individuals had been vaccinated with a Chinese canine vaccine that included modified live CDV, CPV, CAV, CCV, and CPIV. Positive antibody titers were found only against CDV, CPV, and T. gondii. Sera were negative for antibodies against the other six pathogens. Results indicate that the quality of the vaccine may not be reliable and that it should not be considered protective or safe in giant pandas and red pandas. Positive antibody titers against T. gondii were found in seven of the 19 giant pandas. The clinical, subclinical, or epidemiologic significance of infection with these pathogens via natural exposure or from modified live vaccines in giant pandas is unknown. Research in this area is imperative to sustaining a viable population of giant pandas and other endangered species.  相似文献   
45.
Bakeries use sourdoughs to improve bread properties such as flavor and shelf life. The degradation of gluten proteins during fermentation may, however, crucially alter the gluten network formation. We observed changes that occurred in the HMW glutenins during wheat sourdough fermentations. As fermentation starters, we used either rye sourdough or pure cultures of lactobacilli and yeast. In addition, we incubated wheat flour (WF) in the presence of antibiotics under different pH conditions. The proteolytic activities of cereal and sourdough‐derived proteinases were studied with edestin and casein. During sourdough fermentations, most of the highly polymerized HMW glutenins degraded. A new area of alcohol‐soluble proteins (≈30.000 MW) appeared as a result of the proteolytic breakdown of gluten proteins. Very similar changes were observable as WF was incubated in the presence of antibiotics at pH 3.7. Cereal and sourdough‐derived proteinases hydrolyzed edestin at pH 3.5 but showed no activity at pH 5.5. An aspartic proteinase inhibitor (pepstatin A) arrested 88–100% of the activities of sourdough enzymes. According to these results, the most active proteinases in wheat sourdoughs were the cereal aspartic proteinases. Acidic conditions present in sourdoughs create an ideal environment for cereal aspartic proteinases to be active against gluten proteins.  相似文献   
46.
Wheat bran contains good quality protein, but given its location inside aleurone cells, this protein has restricted digestibility. The aim of this work was to liberate and solubilize wheat bran proteins via cell wall degradation by using carbohydrate‐hydrolyzing and proteolytic enzymes without causing extensive protein hydrolysis. Bran incubated with water (without added enzymes) for 16 h increased the solubilized organic nitrogen content from 14.0 to 42.8%. Enzymes with solely carbohydrate‐hydrolyzing activity increased the water‐soluble pentosan and reducing sugar contents but did not significantly increase protein solubilization or protein release from the aleurone cells. Enzymes with proteolytic activity significantly increased the solubilization of protein to 58.2% already at 4 h. Significant protein hydrolysis was detected with a high dosage of protease. However, based on light microscopy, the enzymatic treatment mainly modified the proteins in the subaleurone layer, and it was less effective on proteins inside the aleurone cells. With optimized protease treatment (3 h, 35°C, and 550 nkat/g), effective protein solubilization (>48%) without extensive protein hydrolysis (free amino nitrogen content <45 mg/L) was achieved. In conclusion, intensive solubilization of proteins in the subaleurone layer of wheat bran is possible by using exogenous enzymes with proteolytic activities.  相似文献   
47.
Bran is a good source of dietary fibre, phytochemicals, and also protein, but highly insoluble and recalcitrant structure of bran hinders accessibility of these components for gastrointestinal digestion. In the present work, influence of bioprocessing on the microstructure and chemical properties of rye bran and wheat bread fortified with the rye bran were studied. In vitro protein digestibility, and release of short chain fatty acids (SCFA) and ferulic acid in a gut model were studied. Bioprocessing of rye bran was performed with subsequent treatments with cell-wall hydrolysing enzymes (40 °C, 4 h) and yeast fermentation (20 °C, 20 h). Bioprocessing of rye bran resulted in reduced total dietary fibre content, caused mainly by degradation of fructan and β-glucan, and increased soluble fibre content, caused mainly by solubilisation of arabinoxylans. Microscopic analysis revealed degradation of aleurone cell wall structure of the bioprocessed rye bran. Bioprocessing caused release of protein from aleurone cells, assessed as a larger content of soluble protein in bran and a higher hydrolysis rate in vitro. Bioprocessed bran had also faster SCFA formation and ferulic acid release in the colon fermentation in vitro as compared to native bran.  相似文献   
48.
Fonio plays an important role in food security and in income generation, in drought prone areas of West Africa. This review aimed at highlighting fonio production constraints, breeding objectives and available genetic resources for fonio improvement. Lack of institutional support to research, lack of improved seeds, parasitic weed infestation, grain shattering, lodging and toilsome of the post-harvest handling are the major constraints limiting fonio production. These factors lead to negligence of the crop notwithstanding its high nutritional and market values. Breeding programs on fonio should first focus on solving these problems to improve overall yield. We explored the potential of mutation breeding, somaclonal variation, somatic hybridization, molecular markers, comparative genomics, individualized targeting induced local lesions in genomes (iTILLING), genotype by sequencing and genomic selection to develop improved fonio varieties. Determination of ploidy level, wide collection and characterization of fonio genetic resources, definition of core reference set collection, and exploitation of heterosis are some key research areas that would be of great interest in fonio improvement. However, this can only be achieved with adequate funding and institutional support.  相似文献   
49.
The objective of this study was to estimate and evaluate oxidative/nitrosative stress parameters in sheep infected with Strongyloides papillosus and after antihelminthic treatment with albendazole (ABZ). This parasite, especially during development stages can seriously damage parenchaematous organs during migration within the host. The presence of parasites leads to increased productions of reactive oxygen species (ROS) and reactive nitrogen species (RNS). It is also well known that certain drugs can be very harmful for the delicate oxidant-antioxidant equilibrium, provoking oxidative stress during their biotransformation. ABZ is a broad spectrum antihelminthic drug, frequently used in veterinary medicine for therapy of parasitic infections. The current research was performed on female Württemberg sheep (n=48). The distribution of parasites in sheep was evaluated using the native smear coprological technique, by sedimentation and flotation methods, revealing the presence of S. papillosus. The degree of infection intensity per sheep was quantitatively established by the method of McMaster, the animals having been divided into three groups according to the intensity of infection; mild, moderate and high. The control group consisted of sheep negative to the parasites. After determining the type of parasite infection, the sheep were treated with ABZ, per orally, in single doses of 5mg/kg per body weight. Sampling of feces for parasitological and blood for biochemical assaying was performed on the 0 and 21st day after treatment with ABZ. The oxidative stress parameters were measured for catalase activity (CAT), the red cell membrane damage by level of malondialdehyde (MDA), while carbonyl and thiol plasma protein group concentrations were used as indicators of the degree of protein oxidative modification. The activity of Cu,Zn-superoxide dismutase (SOD) and relative distribution of lactate dehydrogenase (LDH(1)-LDH(5)) activity were determined electrophoretically. The distribution of LDH isoenzymes in sheep moderately and highly infected with S. papillosus revealed that the parasite induced damage to the myocardial (LDH(2)), lung (LDH(3)) and liver cells (LDH(5)) in infected animals, while ABZ treatment only damaged liver cells (LDH(5)). The MDA concentration revealed that lipid peroxidation increased both in the presence of parasites and the antihelminthic formulation tested (p<0.001) when compared to the control sheep, while the increase of carbonyl concentration (p<0.001), as well as the observed decrease of thiol concentration (p<0.001) indicated significant oxidative damage of plasma proteins in experimental sheep, when compared to the control animals. Our results indicate that S. papillosus induces oxidative/nitrosative stress in sheep. The antihelminthic treatment with ABZ further promotes the disbalance of oxidative-antioxidative equilibrium in all tested sheep.  相似文献   
50.
There is minimal published research information on optimal fertilizer rates for growing organic herbs in a greenhouse container system under warm climate in south Florida. Our objective was to determine the optimum organic fertilizer rate for container herb production in a greenhouse for basil (Ocimum basilicum), coriander (Coriandrum sativum), and dill (Anethum graveolens) using Perdue certified organic fertilizer (Agri Recycle, 4–2-3, Seaford, DE) (4N-0.85P-0.25K). The organic fertilizer was mixed with potting medium (Fafard, Conrad Fafard, Inc.; Agawam, MA) at four rates: 0, 10.6, 21.1, and 31.7 g of fertilizer per L of potting medium. Results indicated an increase in nitrogen in plant tissue with an increase in fertilizer rate for all herbs and both trials. Based on statistical results from the fresh and dry weights of the herbs, the Purdue fertilizer rate for optimum production should be between 21.1 and 31.7 g of fertilizer per L of potting media. The lower fertilizer rate (21.1 g) is more attractive for overall production since it would result in a lower cost than using the 31.7 g fertilizer rate. This recommendation is based on the fertilizer chosen, the herb, the potting media, and the location of this study.  相似文献   
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