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91.
The live attenuated Brucella abortus SRB51 (SRB51) is a partial O-chain-deprived mutant. The relative lack of the polysaccharide prevents it from inducing antibodies detectable by most of the serological tests used for the diagnosis of bovine brucellosis. The performance of three antigens used in an indirect enzyme-linked immunoassay test for detecting SRB51 antibodies were evaluated. A homogeneous group of twenty-five 10-month-old Hereford heifers was used. The animals were bled on day 0 and then subcutaneously vaccinated with 2 ml of a commercially available SRB51 vaccine (Schering-Plough) containing 1x10(7) to 3.4x10(7) viable cells. Blood samples without anticoagulant for sera obtaining were then collected at days 30, 90, 210 and 360 post-vaccination. To detect the SRB51 antibodies, Brucella ovis hot saline extract, B. ovis RLPS (RLPS), and SRB51-RLPS were used. The buffered antigen plate agglutination test and an indirect enzyme-linked immunoassay (I-ELISA) using the smooth LPS (SLPS) antigen from B. abortus were used as control tests. All the sera samples were negative in the BPA test and in the standard I-ELISA using the SLPS. The SRB51-RLPS and the B. ovis RLPS antigens performed better than the B. ovis hot saline extract antigen.  相似文献   
92.
The purpose of this study was to determine if treatment of pigs with ketoprofen (3 mg/kg body weight) before castration at 7 days of age would affect subsequent growth during the suckling period. Piglets from 301 litters were treated with ketoprofen or a placebo and weighed at castration and at weaning. There was no difference in growth rate between the 2 groups of pigs.  相似文献   
93.
  1. Illegal wildlife trade is a major global threat to biodiversity. Environmental authorities around the world face many challenges enforcing and implementing laws intended to protect wild species. Wildlife forensic protocols can help to solve many of these implementation and enforcement issues.
  2. Matamata turtles comprise two different species that look identical (Chelus fimbriata, Chelus orinocensis), which are geographically separated into the Amazon and Orinoco river basins, respectively, in South America. The trade in matamata turtles (Chelus sp.) is illegal in Colombia and law enforcement officers need to identify confiscated individuals to the species level in order to return them to the correct river basin. This is a time-sensitive problem because increasing time in captivity can lead to mortality and imposes logistical and financial burdens on resource managers.
  3. This article presents the development of a reliable, potentially field-based, fast (~2 h), and cost-effective (~USD$1 per sample identified) real-time polymerase chain reaction assay to identify live matamata turtles to the species level, which facilitates accurate and fast translocation back to the correct river-of-origin.
  4. This assay was applied in a real law enforcement scenario where confiscated matamata turtles were quickly identified as C. orinocensis, showing that they should be returned to the Orinoco basin. This research highlights the practicality and usefulness of these kinds of protocols to solve wildlife trade issues faced by law enforcement officers, and provides a blueprint for the development and implementation of field-based molecular protocols to enhance the enforcement and implementation of laws intended to protect wildlife subject to illegal trade.
  5. Given the widespread detection of illegal trade in wildlife and the threat that it poses to biodiversity, it is critical that these types of protocols and collaborative efforts among all stakeholders continue to be developed and implemented.
  相似文献   
94.
  1. This study evaluated management effectiveness in three marine protected areas (MPAs) for conservation of the Antillean manatee (Trichechus manatus manatus Linnaeus 1758), located on the eastern coast of the Yucatan Peninsula, Mexico. The MPAs evaluated were the Yum‐Balam Flora and Fauna Reserve, Sian Ka'an Biosphere Reserve, and Chetumal Bay Manatee Sanctuary. The extent of the traditional, popular, and scientific manatee knowledge and research were assessed, as well as the prescribed conservation management actions, relevant stakeholders, and the degree of inclusion of manatee species in the management schemes of these MPAs.
  2. Four general criteria, 12 specific criteria, and 62 indicators were developed. In total, 199 interviews were completed in seven communities of the MPAs in order to determine the perception of the social, economic, and conservation impacts of the manatee and its management.
  3. Although the evaluated MPAs were not wholly comparable among themselves due to their different management categories and schemes, administration, socio‐economic context, and the dynamics and conflicts encountered, a comparison was conducted using standardized criteria and a categorical scale in order to evaluate the level of effectiveness of each MPA.
  4. The MPA with the highest management effectiveness in manatee conservation was found to be the Chetumal Bay, with an effectiveness classed as good (71%), followed by Sian Ka'an with intermediate effectiveness (53%) and Yum‐Balam, also with intermediate effectiveness (43%).
  5. The relationships between the key stakeholders of the three MPAs and economic activities such as fishing and tourism are the factors that most influence the effectiveness of management for manatee conservation.
  相似文献   
95.
'Mal seco' is a grass sickness-like syndrome of horses in Argentina. A histopathological study was made of the coeliaco-mesenteric ganglia of four horses with 'mal seco' and of four horses that died from other causes. The severity and extent of the lesions found in the horses with 'mal seco' was greatest in the two with the shortest clinical course. Degenerative changes consisted mainly in the loss of Nissl substance, cytoplasmic vacuoles, neuronophagia, intercellular and intracytoplasmic eosinophilic bodies, and pyknotic and eccentric nuclei. The coeliaco-mesenteric ganglia of the control horses had no histological lesions. The histological lesions in the horses with 'mal seco' were very similar to those described in the coeliaco-mesenteric ganglia of horses with grass sickness in Europe and it is suggested that 'mal seco' and grass sickness may be the same disease.  相似文献   
96.
This report describes an unusual presentation of severe focal necrotic tracheitis in a flock of 8-wk-old commercial turkeys. The flock was kept on a range that is located near a cotton field. The cotton field had been chemically defoliated 2 wk before the birds were submitted for necropsy. At necropsy, most of the birds had a 1-cm, yellow-white constricture in the upper third of the trachea at which the lumen was partially occluded by necrotic tissue. Microscopically, there was severe, transmural necrosis with an accumulation of inflammatory exudate in the tracheal lumen and numerous bacteria within the necrotic debris, mucosa, and lamina propria. Mixed bacteria were isolated from the trachea. No viruses were detected. Neither abnormal heavy metal concentrations in the liver nor paraquat in the respiratory tract were detected. The exact cause of this severe, necrotic tracheitis was not determined. Based on the clinical history and laboratory findings, it was concluded that a combination of a toxic irritant, possibly an aerosolized cotton defoliant, and bacterial infections were likely the cause of this lesion.  相似文献   
97.
Histomoniasis was diagnosed in a flock of 6-wk-old commercial chickens. Clinical signs included depression, stilted gait, inappetence, and a slight increase in mortality. At necropsy, there were pale-yellow to dark-gray circular and depressed necrotic lesions in the liver. The ceca were enlarged and impacted with caseous cores. Cecal worms were not observed either at necropsy or on histopathology. Histomonads were demonstrated microscopically within the bursa of Fabricius in addition to the liver, ceca, and spleen. This is the first report of the presence of histomonads in the bursa of Fabricius in commercial chickens.  相似文献   
98.
A 5-mo-old great rhea (Rhea americana) gradually became emaciated over a 1-wk period and died. Necropsy revealed several small yellow nodules in the lungs. Microscopically, the nodules consisted of granulomas containing numerous thin, 4-microm-diameter, septate, branching fungal hyphae. Aspergillus fumigatus grew readily on Sabouraud dextrose agar. This report appears to be the first of mycotic pneumonia in great rheas.  相似文献   
99.
Prevalence, causative factors, treatment, and preventative measures for O149:K91:F4 Escherichia coli infection of postweaning pigs was determined by using a cross-sectional study including 70 farms in Ontario. Surveys were distributed and samples cultured bacteriologically, resulting in 30% of farms testing positive to E. coli 0149:K91:F4. Possible causative factors, such as housing or nutrition, were not significantly different between positive and negative farms. Use of injectable antibiotics (P = 0.05) and zinc oxide (P = 0.003) was higher on E. coli O149:K91:K88 (F4)-positive farms. A higher level of biosecurity and the presence of other diseases may be associated with an increased risk of isolating E. coli O149:K91:F4 from weanling pigs.  相似文献   
100.
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