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381.
Cristine Cerva Carolina Bremm Emily Marques dos Reis André Vinícius Andrade Bezerra Márcia Regina Loiko Cláudio Estêvão Farias da Cruz Alexander Cenci Fabiana Quoos Mayer 《Tropical animal health and production》2014,46(5):877-882
While human illness from milkborne pathogens may be linked to contamination of the product after pasteurization or improper pasteurization, such diseases are usually associated with consumption of raw milk or its by-products. Molecular biology tools were applied to investigate contamination by Listeria monocytogenes, Salmonella spp., some pathogenic strains of Escherichia coli, and Campylobacter jejuni in 548 raw milk samples from 125 dairy farms established in two regions from southern Brazil. Moreover, 15 variables were evaluated for their association with raw milk contamination levels, and the risk factors were determined by multiple regression analysis. Salmonella spp. were more frequently detected, followed by pathogenic E. coli. There was difference in contamination index between the regions, in which risk factors such as temporary cattle confinement, low milk production, low milking machine cleaning frequency, and milk storage area without tile walls were identified. The risk factors were specific to each region studied. Nevertheless, the data can be used to improve milk quality of dairy farms/herds with similar management practices. 相似文献
382.
Rita Maria Alves de Moraes Tais Cristina Bastos Soares Lucinete Regina Colombo Maria Fernanda Spegiorin Salla Josie Gomes de Almeida Barros Newton Deniz Piovesan Everaldo Gonçalves de Barros Maurilio Alves Moreira 《Euphytica》2006,149(1-2):221-226
Summary The antinutritional factors found in soybean, lectin (SBL) and Kunitz trypsin inhibitor (SKTI), are usually inactivated by heat treatment. However, residual activity of these factors can be found in several types of soy-derived products. Heat treatment does not completely eliminate these factors, and in addition it may considerably decrease protein solubility. The genetic elimination of these antinutritional factors could be an alternative to the heat treatment. This study aimed to develop soybean lines devoid of SKTI and SBL in their seeds. The population under study was obtained by crossing the normal cv. Monarca with a soybean line lacking SKTI and SBL. Specific DNA primers were designed for the identification of the recessive alleles that condition the absence of SKTI and SBL. F2 seeds presenting the DNA markers that identify the recessive alleles were selected and the corresponding F2 plants were backcrossed with the recurrent parent (‘Monarca’), producing the BC1F1 generation. The F2 generation was analyzed by SDS-PAGE in order to confirm the genotypes of the F2 selected. The segregation tests confirmed that these traits are governed by two genes that segregate independently. 相似文献
383.
Luc Hippolyte Dossa Barbara Rischkowsky Regina Birner Clemens Wollny 《Agriculture and Human Values》2008,25(4):581-592
An understanding of factors influencing the decision of rural people to keep sheep and/or goats is crucial when formulating
technologies and policies that support village-based small ruminant production. The knowledge of such factors will also improve
assessment of impact intervention strategies on the livelihoods of rural people. Structured questionnaires administered in
228 households were used to study the ownership patterns of small ruminants in southern Benin. The ownership of goats was
higher (91%) than sheep (35%) because goats are not affected by any ethnic or cultural restrictions. Goats are also perceived
to be a less risky to invest into compared to sheep. Women represented 71% of the keepers of goats. Predictive models of ownership
were developed using logistic regression. The results showed that younger household members (p < 0.05) especially young women (60%) are more likely to own small ruminants. Owners of small ruminants are less likely to
be involved in off-farm activities and would often have no access to credit facilities. Gender, ethnicity, and perception
of risk associated with species are the major factors affecting people’s choice of species. These findings highlight the financing
and insurance roles that small ruminants, particularly goats, are playing in the study area. In order to develop suitable
technologies and formulate policies to improve productivity and enhance livelihoods, the constraints to goat production need
to be identified, and the local knowledge of the keepers should be investigated.
相似文献
Luc Hippolyte DossaEmail: Email: |
384.
Concepta McManus Giane Regina Paludo Helder Louvandini Rosilene Gugel Luiz Cláudio Bastos Sasaki Samuel Rezende Paiva 《Tropical animal health and production》2009,41(1):95-101
Thirty Santa Ines adult, non-lactating, non-pregnant ewes, ten with a brown coat, ten black coated and ten white coated, as well as ten Bergamasca and ten of mixed breed were used to evaluate the effect of climate on physiological and blood parameters in sheep. Two sample collections were taken (6 am and 2 pm) on six days. Sweating rate (SR), heart (HR) and breathing rates (BR), complete hemogram, rectal (RT) and skin temperatures (ST) were measured. Variance analyses were carried out using SAS®. In general, there were significant differences between animals due to skin type, time and day of collection. White coated animals showed lower HR, BR and RT, with afternoon parameters higher than morning. Correlations between HR, BR, RT, SR and ST were medium and positive. Correlations between physiological and blood traits were in general negative and medium. Packed Cell Volume (PCV), total plasma proteins, red blood cell count and hemoglobin concentration had high positive correlations between each other. The first two autovectors explained 49% of variation between traits. White coated Santa Ines animals were shown to be better adapted to climatic conditions in Central Brazil and wool sheep more affected by heat. 相似文献
385.
dos Santos DR Vitral CL de Paula VS Marchevsky RS Lopes JF Gaspar AM Saddi TM Júnior NC Guimarães Fde R Júnior JG Ximenes LL Souto FJ Pinto MA 《Veterinary journal (London, England : 1997)》2009,182(3):474-480
Active hepatitis E virus (HEV) infections in two Brazilian swine herds were investigated. In study 1, 26 piglets born to five anti-HEV positive sows were monitored from birth to post-partum week 22. Serum samples were screened for the detection of anti-HEV antibodies and a nested RT-PCR used to examine the HEV genome. Passive transfer of immunity was confirmed. At week 22, 23/26 (88.4%) of the piglets had seroconverted. Genome amplification was achieved in a feces pool from one holding pen and in one serum sample, both from 13-week-old animals. Histology was suggestive of a potential HEV infection. In the second study, 47 piglets born to six anti-HEV-positive sows were monitored after weaning. Seroconversion was determined in eight animals at 6-8 weeks of age. HEV RNA was detected in two pools from a holding pen for 12-16-week-old animals. Brazilian isolates were classified as genotype 3. This is the first molecular evidence of HEV infection in Brazilian pig herds. 相似文献
386.
Acetylene, dimethyl ether (DME) and 2-chloro-6-trichloromethyl pyridine (nitrapyrin) were used as inhibitors to study the
contributions of nitrification and denitrification to the production of N2O and nitric oxide (NO) in samples taken from the soil profile of a peatland drained for forestry. Acetylene and DME inhibited
60–100% of the nitrification activity in field-moist samples from the 0–5 cm and 5–10 cm peat layers, whereas nitrapyrin had
no inhibitory effect. In the 0–5 cm peat layer the N2O production could be reduced by up to 90% with inhibitors of nitrification, but in the 5–10 cm peat layer this proportion
was 20–30%. All the inhibitors removed 96–100% of the nitrification potential in peat-water slurries from the 0–5 cm peat
layer, but the 5–10 cm layer had a much lower nitrification activity, and here the efficiency of the inhibitors was more variable.
Litter was the main net source of NO in the peat profile. NO3
– production was lower in the litter layer than in the peat, whereas N2O production was much higher in the litter than in the peat. Denitrification was the most probable source of N2O and NO in the litter, which had a high availability of organic substrates.
Received: 14 July 1997 相似文献
387.
Osnan Lennon Lameira Silva Antnia Rafaela Gonalves Macedo Emília do Socorro Conceio de Lima Nunes Keila Diniz Campos Leiliane Cristina Cardoso Araújo Xenna Tiburo Anne Suellen Oliveira Pinto Maria Regina Sarkis Peixoto Joele Micheli da Silva Ferreira Ana Carolina Ramos da Silva Renata Santana Lorenzo Raices Adriano Gomes da Cruz Leandro Juen Rossineide Martins da Rocha 《Aquaculture Research》2020,51(6):2336-2348
The objective of this study was to evaluate the effect of environmental factors on the fatty acid profiles and physicochemical composition of Crassostrea gasar cultured in two locations with differences in salinity and precipitation gradients. The study period was divided into four seasonal divisions—the rainy–dry transition period, the dry season, dry–rainy transition and the rainy season. The salinity, pH and temperature were measured at each site during specimen collection. A total of 712 oyster samples were used for fatty acid profiling and physicochemical analysis. Salinity and precipitation were the environmental parameters that influenced the fatty acid profile and physicochemical characteristics of oysters. C. gasar exhibited excellent values of n3 polyunsaturated fatty acids (DHA, EPA and eicosatrienoic), with a predominance of these acids during periods of higher precipitation. Variations in precipitation and salinity resulted in significant differences in oyster nutritional characteristics. Oysters grown in Amazonian estuaries can be considered nutritious throughout the year, with better conditions during the rainy season. 相似文献
388.
A comparison between water exchange and settling tank as a method for suspended solids management in intensive biofloc technology systems: effects on shrimp (Litopenaeus vannamei) performance,water quality and water use 下载免费PDF全文
Rafael Arantes Rodrigo Schveitzer Caio Magnotti Katt Regina Lapa Luis Vinatea 《Aquaculture Research》2017,48(4):1478-1490
Biofloc systems rely on microbial processes in the water column to recycle animal waste products, reducing the need for water exchange. These increases biofloc concentration in the water and some form of removal is needed. An experiment was carried out to evaluate two management practices to control biofloc in Litopenaeus vannamei culture. Six tanks (48 m3) were divided into two treatments: water exchange and solid settler. Shrimp were stocked at 164 shrimp m?2 and with 0.67 g of weight. After 61 days, shrimp under solid settler treatment demonstrated mean weight of 12.7 ± 0.5 g with survival of 73.8 ± 1.4%, and those under water exchange had a final weight of 10.1 ± 0.2 g and survival rate of 57.8 ± 11.1%. Total suspended solids did not differ between the treatments: 326.8 ± 24.9 mg L?1 for water exchange and 310.9 ± 25.3 mg L?1 for solid settlers. Settleable solids and productivity/respiration ratio was higher (P < 0.05) in water exchange treatment, indicating differences in physical and biological characteristics of bioflocs. Solids removal method influenced the water use, in which 1150 ± 249 L of water was necessary to produce one kilogram of shrimp using water exchange strategy, and 631 ± 25 L kg?1 with the use of settlers. Our results indicate that continuous operation of settlers can reduce variability in solids characteristics and water quality variables such as ammonia. Both strategies are efficient in controlling biofloc concentrations of the water; however, settlers can reduce water use and improve shrimp production. 相似文献
389.