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排序方式: 共有1738条查询结果,搜索用时 15 毫秒
81.
Ullmann LS Hoffmann JL de Moraes W Cubas ZS dos Santos LC da Silva RC Moreira N Guimaraes AM Camossi LG Langoni H Biondo AW 《Journal of zoo and wildlife medicine》2012,43(2):223-228
Leptospirosis is a bacterial zoonosis of worldwide distribution and is endemic in tropical countries, where rodents and other wild mammals are abundant and may act as reservoirs. Leptospirosis has become a concern in captive wild animals, due mostly to their exposure to contaminated urine or environment. Although domestic cats (Felis catus) have been reported refractory to leptospirosis, serology and disease in captive wild felids is still unclear. In this study 57 adult, clinically healthy felids, including 1 Geoffroy's cat (Leopardus geoffroyi), 3 jaguarundis (Puma yagouaroundi), 17 margays (Leopardus wiedii), 22 little spotted cats (Leopardus tigrinus), and 14 ocelots (Leopardus pardalis) kept in captivity at the Sanctuary at the Itaipu Binacional hydroelectric power plant (Bela Vista Biological Sanctuary), Foz do Iguacu City, Paraná State, Brazil, were serologically surveyed for the presence of antibodies against 28 serovars of Leptospira spp. by microagglutination test (MAT). Two animals (3.5%) were seropositive: one male ocelot to the serovar Cynopteri (titer 100) and one female margay to Autumnalis (100) and Butembo (200). The captive-born, 5-yr-old ocelot had been solitary housed in an individual cage. The approximately 21-yr-old wild-caught margay was also kept individually. None of the tested animals showed signs ofleptospirosis. During a study conducted 4 yr previously in the same facility, this particular margay also tested positive for the same two serovars, among others. The present study indicates that the felids tested for Leptospira spp. by MAT were exposed to serovars, but did not demonstrate clinical signs of disease. Comparison with a previous study suggests that serovar titers may vary over time and that leptospirosis dynamics remains unclear in wild felids. 相似文献
82.
Marconni Victor da Costa Lana Noemi Rovaris Gardinali Raquel Aparecida Sales da Cruz Letícya Lerner Lopes Gustavo Sousa Silva João Garcia Caramori Júnior Anderson Castro Soares de Oliveira Marcos de Almeida Souza Edson Moleta Colodel Amauri Alcindo Alfieri Caroline Argenta Pescador 《Tropical animal health and production》2014,46(2):399-404
The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n?=?5) or family-scale farms (n?=?5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State. 相似文献
83.
Effects of temperature on growth,survival and physiological parameters in juveniles of Lophiosilurus alexandri,a carnivorous neotropical catfish 下载免费PDF全文
Daniel Pereira da Costa Fabíola de Oliveira Paes Leme Rodrigo Takata Deliane Cristina Costa Walisson de Souza e Silva Reinaldo Melillo Filho Gabriela Miccoli Alves Ronald Kennedy Luz 《Aquaculture Research》2016,47(6):1706-1715
This study aimed to analyse the effects of different water temperatures on the growth, survival and blood physiological parameters of Lophiosilurus alexandri. Juveniles measuring 12.6 ± 0.5 cm and weighing 30.6 ± 3.6 g were subjected to four water temperature regimes: 23, 26, 29 and 32°C with four replicates. The animals were fed twice daily with formulated diet. The experiment lasted for 35 days. Survival was 100% at all water temperatures, and the best temperature for growth was estimated to be 27.8°C using a quadratic regression model. The estimated temperatures for the best feed conversion and highest feed consumption rates were 26.2 and 28.8°C respectively. The fat visceral‐somatic index was highest at 32°C. The highest haemoglobin and haematocrit values were 29.4 and 32.1°C respectively. For plasma protein and cholesterol, the lowest values estimated were 23.9 and 24.1°C respectively. Glucose and liver nitrogen content increased with rising temperature. Higher values of total ammonia in the water were observed at higher temperatures. No effects of temperature were seen on the amounts of muscle dry matter, nitrogen, energy content and triglycerides or on the hepatosomatic index. Water temperature has an important role in the developmental and blood physiological parameters of juvenile L. alexandri, and the quadratic regression model showed that the appropriate temperature for growth is between 27 and 28°C. 相似文献
84.
85.
Phelipe M. Oller Costa Cristina M. Souza-Motta Elaine Malosso 《Agroforestry Systems》2012,85(1):195-203
Microbial population and activity can be influenced by changes in the physical and chemical conditions of the soil. The objective of this study was to compare fungal diversity under different agricultural management systems and associated differences in soil properties. This research was carried out in three areas, representing the Atlantic Forest, AFS and cassava (Manihot esculenta Crantz) monoculture system. Five composite samples were collected during the rainy and dry seasons from each area. Using the composite soil samples, fungal isolation was carried out using a serial dilution technique. Physical, chemical and DGGE analyses of the filamentous fungi community were performed. The fungal isolation data were used to calculate ecological indices of diversity, species richness, equitability, dominance, similarity and density. In general, Atlantic Forest soil presented the highest ecological indices followed by the AFS. The DGGE technique revealed that the structure of the soil mycobiota of the Atlantic Forest and AFS are more than 50% similar. The data indicate that the similarity of the structure and composition of soil mycobiota between AFS and Atlantic Forest is mainly due to the conservation of above-ground plant diversity, and the conservation of soil characteristics can be attributed to the absence of pesticides and fertilizers. 相似文献
86.
Polymethylmethacrylate orbital implants with interconnecting channels. A retrospective study following enucleation in dogs and cats 下载免费PDF全文
87.
88.
G. L. Lima E. A. A. Santos V. B. Luz A. P. R. Rodrigues A. R. Silva 《Anatomia, histologia, embryologia》2013,42(4):304-311
The aim of this research was to characterize the preantral ovarian follicular population in collared peccaries (Tayassu tajacu) using light and electron microscopy. Ovaries from six mature females were collected and further fixed for histological and ultrastructural analysis. A total of 33273.45 ± 5789.99 preantral follicles (PFs) were estimated for the population in each ovary. Most preantral follicles were primordial (91.56%), followed by primary (6.29%) and secondary (2.15%) ones. Most PFs were morphologically normal (94.4%), and only a few were atretic (5.6%). At histology assessment, amounts of lipid droplets were observed into the oocyte cytoplasm, which was confirmed through ultrastructural analysis. This work characterizes for the first time the ovarian population of preantral follicles, total and per category, in collared peccaries (Tayassu tajacu). The general follicles featured at primordial, primary and secondary categories are very similar to those described for other species. 相似文献
89.
90.
In order to study the morphology and morphometry and to characterize and quantify the nucleolar organizer regions (NORs) of bovine thyroids containing methylthiouracil (MTU) residues, five animals were orally treated with a suspension of MTU (5 g/animal/day) for 20 days (group A). This treatment protocol was interrupted 5 days before the the animals were slaughtered. Six animals receiving placebos composed group B. A third group (group C) was composed of normal thyroids obtained from a slaughterhouse. All glands were previously assessed for detection of antithyroid residues by chromatography, and only those glands from MTU-treated animals were positive. Follicles of glands from group A showed wide variation in size and shape. There was a predominance of small follicles covered by multiple layers of columnar cells, sometimes forming papillary projections into the lumen, characterizing severe interfollicular and intrafollicular adenomatosis. Many follicles had vacuolated cells with nuclei showing karyolysis or pyknosis and reduced amounts of a low-density and very excavated colloid. They also showed higher follicular epithelia and larger proportions of their structural components when compared with glands of groups B and C. In the thyroids from group A, the argyrophilic nucleolar organizer region-associated proteins (AgNORs) were greater in number, with small ones scattered all over the nucleus. Although the size of AgNORs in thyroids from groups B and C was variable, these AgNORs were fewer and larger than were those in glands from group A. In conclusion, the MTU induces proliferation and regressive changes in follicular cells, and the AgNOR technique is efficient to distinguish different degrees of thyroid hyperplasia. 相似文献