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31.
The use of nitrofurans as veterinary drugs has been banned from intensive animal production in the European Union (EU) since 1993. The objective of the present study was to evaluate the accumulation and depletion of furaltadone and nifursol and their side-chain metabolites 5-methylmorpholino-3-amino-2-oxazolidinone (AMOZ) and 3,5-dinitrosalicylic acid hydrazide (DNSAH) in eggs after administration of therapeutic and subtherapeutic doses of the drugs to laying hens during three consecutive weeks. LC-MS/MS, with positive and negative electrospray ionization methods, was used for the determination of parent compounds and metabolites in yolk and egg white and was validated according to criteria established by Commission Decision 2002/657/EC. The decision limit (CCα) and the detection capability (CCβ) of the analytical methodology for metabolites were 0.1 and 0.5 μg/kg for AMOZ and 0.3 and 0.9 μg/kg for DNSAH, respectively. For the parent compounds, CCα and CCβ were 0.9 and 2.0 μg/kg for furaltadone and 1.3 and 3.1 μg/kg for nifursol, respectively. The data obtained show that the parent compounds are much less persistent than their side-chain metabolites in either yolk or egg white. Between the studied metabolites, AMOZ is the most persistent and could be detected in either yolk or egg white three weeks following withdrawal from treatment.  相似文献   
32.
Visceral leishmaniasis is a disease caused by Leishmania (Leishmania) chagasi and represents a serious public health problem. The dog is the main urban reservoir of the disease; however, investigations regarding the occurrence and epidemiological importance of leishmaniasis in cats have recently been initiated. This study aimed to detect cats seropositive for Leishmania spp. using different antigens. Additional studies were performed using sera from cats with Toxoplasma gondii (n=15) to evaluate cross-reactivity. Serum samples (n=113) from cats living in the town of Ara?atuba, State of S?o Paulo, Brazil, an endemic area for human and canine visceral leishmaniasis, were tested by indirect ELISA using different antigens: crude (CAG-ELISA), fucose-mannose ligand (FML-ELISA) and K39 (rK39-ELISA). Anti-Leishmania spp. antibodies were detected in 23.0% of samples evaluated by CAG-ELISA, 13.3% by FML-ELISA and 15.9% by RK39-ELISA. Only reactive sera in all three tests were considered truly positive. No disagreement occurred among the tests (p<0.05). Serum samples seropositive for toxoplasmosis tested by CAG-ELISA were negative, but one sample (6.7%) was positive for FML-ELISA and rK39-ELISA suggesting a cross-reaction between these antigens and anti-T. gondii antibodies. These findings indicate the occurrence of feline leishmaniasis in Ara?atuba. Further studies are required to clarify the role of cats in the epidemiological cycle of leishmaniasis.  相似文献   
33.
We have studied the variability of glutamate dehydrogenase (gdh) and small subunit ribosomal (SSU) rRNA coding genes of Giardia species in fecal samples isolated from wild and exotic animals in Brazil, and compared with homologous sequences of isolates from human and domestic animals characterized in previous studies. Cysts of Giardia duodenalis were obtained from feces of naturally infected monkeys (Alouatta fusca) (n=20), chinchillas (Chinchilla lanigera) (n=3), ostriches (Struthio camelus) (n=2) and jaguar (Panthera onca) (n=1). Assemblage AI was assigned to the unique isolate of jaguar. All the samples from monkeys, chinchillas, and ostriches were assigned to Assemblage B. There was little evolutionary divergence between the referred isolates and isolates described elsewhere. The Assemblage B isolates identified in this study were closely related to Assemblage BIV isolated from humans. The molecular identification of Assemblages A and B of G. duodenalis isolates from exotic and wild animals demonstrates that such hosts may be a potential reservoir for zoonotic transmission of G. duodenalis.  相似文献   
34.
35.
The neural system plays an important role in understanding some features of animals. Anatomical complexity correlates with the increase of functional capacity. Xenarthrans include anteaters (Vermilingua), armadillos (Cingulata) and sloths (Folivora). This group is the base of eutherian mammals, and understanding the anatomy of its neural system could provide data for functional and evolutionary interpretations. The gross anatomy of the xenarthran brain is recorded. Four extant families of Pilosa and two families of Cingulata were sampled. Usual dissection procedures were used, and the brains were analysed macroscopically. The brain of two-toed sloth, three-toed sloth, six-banded armadillo, giant anteater and collared anteater are gyrencephalic. Pygmy anteater, nine-banded armadillo, great long-nosed armadillo, southern naked-tailed armadillo and giant armadillo are lissencephalic. In most species, the rhinal fissure presents two segments, rostral and caudal (except in Vermilingua and three-toed sloth). The diencephalon and brainstem present similar anatomy. The cerebellum is wide and presents four lobes (rostral, central, caudal and floccular). Its average volume is 12.16% (Folivora), 14.26% (Vermilingua) and 18.61% (Cingulata). Among these groups, there is a statistical difference between Folivora/Cingulata concerning the cerebellum average. The general pattern of the brain of the xenarthrans is similar to that of other mammals.  相似文献   
36.
Criollo horse breeding is an important economic activity in South America. Because of their athletic performance, these animals tend to show great incidence of musculoskeletal disorders, many of them diagnosed by means of perineural blocks. However, incorrect interpretation of these blocks may be due to anatomical differences in nerve distribution. The objective of this study was to describe the innervation of the digit region of thoracic limbs in Criollo horses, in order to improve the interpretation of tests for claudication diagnosis based on nerve block. Thirty thoracic limbs from Criollo horses were dissected. It could be observed that in 90% of the limbs, dorsal branches of the palmar nerve originated proximally to the proximal sesamoid bone. In 93% of the cases, the palmar digital nerve and the dorsal branches communicated; in 87% of the cases, communication between branches of the dorsal branch was observed; and in 27% (8/30) of the limbs, the palmar metacarpal nerve and the dorsal branch presented communications. None of the specimens showed complete symmetry in the distribution of nerves in contralateral limbs. The high frequency of communication between the nerves may be a particularity of the Criollo breed that may interfere with the interpretation of perineural blocks. Based on the anatomical position, it may be inferred that divergent results in Criollo horses may occur when abaxial sesamoid nerve block is used. Palmar digital nerve block may be less influenced by these variations, provided it is performed as distal as possible from the ungular cartilage.  相似文献   
37.
Recent data show composting as an alternative for treatment of PAHs contaminated wastes. Nevertheless, the presence of highly volatile compounds like naphthalene might compromise the interest of this treatment and thus its careful evaluation is justified. A bench scale composting system was built to evaluate the importance of volatilization in the transformation of naphthalene by composting. Naphthalene concentration was measured in solid, aqueous and gas phases by HPLC and GC. Preliminary results have shown that the presence of microorganisms able to degrade naphthalene reduces naphthalene loss by volatilization.  相似文献   
38.
Pesticides, such as herbicides can affect the metabolic and toxicological parameters on fish. For this reason, an experiment was carried out with the objective of to evaluate the effects of commercial formulations of clomazone and propanil herbicides on acetylcholinesterase (AChE), thiobarbituric acid-reactive substances (TBARS), catalase (CAT) and metabolic parameters in teleost fish (Leporinus obtusidens). Fish were exposed during 90 days to field measured concentration of the herbicides clomazone and propanil (376 and 1644 μg/L, respectively) on rice paddy water. Specific AChE activity in the brain and muscle decreased and TBARS levels decreased in brain, muscle and liver tissues. Liver catalase decreased after exposure to both herbicides. Metabolic parameters in the liver and white muscle showed different changes after exposure to both herbicides. In summary, the results showed that clomazone and propanil affects toxicological and metabolic parameters of piavas. These results suggest that environmentally relevant herbicides concentrations are toxic to Leporinus obtusidens.  相似文献   
39.
The objective of this study was to evaluate how Rhyzopertha dominica infestation of stored wheat grain affects the rheological and baking properties of bread made with the milled flour. Wheat samples were infested with R. dominica and stored for up to 180 days at room temperature. Every 45 days, samples of wheat were collected and evaluated for insect population and flour yield. Flour milled from these wheat samples was evaluated for color reflectance, pH, fat acidity, and rheological properties which were measured by a farinograph. Loaves of bread were baked using a straight-dough procedure. Volume, height, and weight of the loaves were evaluated. None of the analyses performed on the control wheat flours showed any changes during the storage period, and they were similar to the initial wheat. The insect population increased during storage of the wheat up to 90 days, and the flour yield decreased with the storage up to 180 days. Flours from insect-infested wheat absorbed more water than did flours from control wheat. Dough stability and dough development times of infested flours decreased. Bread volume showed a progressive decline throughout the storage experiment. In conclusion, flour from insect-infested wheat exhibited changes in rheological properties such as dough stability, dough development times, water absorption, and mixing stability; bread had an offensive odor; and volume and loaf characteristics were negatively affected.  相似文献   
40.
The increasing cost of commercial fertilizers and environmental problems associated with improper fertilization management have prompted the need to re‐examine commercial N sources that can effectively supply N to pastures while minimizing N losses. This 3‐year study evaluated the effects of selected N sources on bahiagrass (Paspalum notatum Flügge) responses, soil properties and N losses. Treatments consisted of a factorial combination of 6 N sources [(i) ammonium nitrate (AN), (ii) ammonium sulphate (AS), (iii) urea (U), (iv) urea treated with Agrotain (U + Agrotain), (v) SuperU and (vi) ammonium sulphate nitrate] and 3 N levels (0, 60 or 120 kg ha?1 year?1), replicated three times. Bahiagrass dry‐matter yield (DMY), crude protein (CP) concentration, N uptake and recovery were not affected by N source, with the exception of AN that resulted in reduced DMY in 2010 compared with the other sources. Bahiagrass DMY, CP concentration, N uptake and recovery increased linearly as N levels increased. Nitrogen fertilization showed no effect on soil pH or soil N accumulation. Soil pore‐water N concentrations from treatments fertilized with N were similar to the control plots indicating no threat to the environment. At the N levels evaluated in this study, selection of N source should be based on the fertilizer cost.  相似文献   
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