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We hypothesized that organic matter (OM) content originating from treated wastewater (TWW) irrigation and soil texture dominate the intensity of soil water repellency. The relationship between soil texture, wastewater treatment level, and water repellency was examined in a 3-year lysimeter experiment (2008–2010). Soil type–water quality combinations, consisting of three soils with different specific surface area (SSA) and four levels of water quality differing in OM content, were tested. In each year, water repellency developed in all TWW quality treatments, but not in freshwater-irrigated controls. At the end of each year (except 2009), the highest degree of repellency was exhibited by sandy soil treated with the lowest quality TWW (highest OM content). The lowest degree of water repellency was consistently exhibited by the soil with the highest SSA irrigated with the highest quality TWW (lowest OM content). Water quality, rather than SSA, was the dominant factor in determining degree of repellency induced by TWW irrigation.  相似文献   
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A total of 750 faecal samples of dairy calves at up to 2 months of age kept in various housing systems were screened for Cryptosporidium spp. infection using the aniline-carbol-methyl violet staining method. DNA was extracted from Cryptosporidium positive samples and from 150 randomly selected microscopically negative samples. Nested PCR was performed to amplify the partial SSU rRNA gene of Cryptosporidium that was subsequently digested by SspI, VspI and MboII restriction enzymes to determine the present Cryptosporidium species and genotype. In addition, the samples characterized as Cryptosporidium parvum were subsequently analyzed at the GP60 gene to determine the distribution of zoonotic subtypes. Sequence analyses and RFLP identified C. parvum in 137, Cryptosporidium andersoni in 21 and Cryptosporidium bovis in 3 samples. Neither mixed infections nor Cryptosporidium ryanae was detected. Sequencing of the GP60 gene from C. parvum-positive samples revealed all five subtypes of family IIa (A15G2R1, A16G1R1, A22G1R1, A18G1R1, and A15G1R1). The obvious management-associated distribution of Cryptosporidium spp. was demonstrated. Direct contact with adult animals was found to be a risky factor for C. andersoni and C. bovis infection. IIaA15G2R1 and IIaA16G1R1 were detected as major subtypes, whereas only the IIaA16G1R1 subtype was found in animals kept in boxes. Three of the five detected subtypes were previously associated with human cryptosporidiosis, and moreover, the IIaA15G1R1 subtype, previously reported in humans only, was detected in calves for the first time.  相似文献   
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Envenomation of domestic animals by snakes occurs frequently in certain geographic areas. However, reports describing clinical signs, clinicopathologic abnormalities, therapeutic approaches, and outcomes are sparse. This review summarizes various snake families, venom types associated with harmful snakes, and the significant hematologic, hemostatic, and biochemical abnormalities associated with envenomation. Hematologic abnormalities include RBC membrane abnormalities, hemolysis, hemoconcentration, leukogram changes, and platelet abnormalities, specifically thrombocytopenia. Coagulopathies associated with snake envenomation are well described in human medicine, and many studies have demonstrated properties of venoms that lead to both procoagulation and anticoagulation. As expected, similar abnormalities have been described in domestic animals. Biochemical abnormalities are associated with the effects of venom on tissues such as liver, skeletal and cardiac muscle, vascular endothelium, and kidney as well as effects on protein components and cholesterol. This comprehensive review of clinicopathologic abnormalities associated with envenomation and their relationships to characterized venom constituents should be useful both in the diagnosis and management of envenomation and should serve as a foundation for future research in this field.  相似文献   
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Toxic neutrophils exhibit a variety of nuclear and cytoplasmic abnormalities in Romanowsky-stained blood smears, and are associated with inflammation and infection. The purpose of the retrospective study reported here was to investigate the association of toxic neutrophils with clinicopathologic characteristics, diseases, and prognosis in cats. Cats with toxic neutrophils (n = 150) were compared with negative-control cats (n = 150). Statistical analyses included Fisher exact, independent t-, nonparametric Mann-Whitney, and chi-squared tests. Cats with toxic neutrophils had significantly (P < .05) higher prevalence of fever, icterus, vomiting, diarrhea, depression, dehydration, weakness, and cachexia, as well as leukocytosis, neutrophilia, left shift, neutropenia, anemia, hypokalemia, and hypocalcemia. The prevalence of shock, sepsis, panleukopenia, peritonitis, pneumonia, and upper respiratory tract diseases was significantly higher among these cats, as were infectious (viral and bacterial) and metabolic disorders. Control cats had a significantly higher prevalence of feline asthma, as well as allergic, idiopathic, and vascular disorders. Hospitalization duration and treatment cost were significantly (P < .001) higher in cats with toxic neutrophils. In 53 and 47% of the cats with toxic neutrophils, the leukocyte and neutrophil counts were normal, respectively, whereas in 43%, both abnormalities and left shift were absent, and toxic neutrophils were the only hematologic evidence of inflammation or infection. In conclusion, toxic neutrophils were found to be associated with certain clinicopathologic abnormalities, and when present, may aid in the diagnosis, as well as the assessment of hospitalization duration and cost. The evaluation of blood smears for toxic neutrophils provided useful clinical information.  相似文献   
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Magnesium (Mg) and calcium (Ca) are the main divalent cations in the body. The free ionized fraction is the physiologically active form of both Mg and Ca. As ion-selective-electrode (ISE) analyzers are becoming widely used in veterinary practice it will be useful to establish reference intervals for horses. In the present study, reference intervals were established for ionized, total and the ratio of the ionized to total Mg and Ca concentrations in four horse groups: adults, neonatal foals, and pregnant and lactating mares, as well as in three sample types, whole blood, plasma and serum, using an ISE-analyzer. Sample pH effect was assessed.Concentration differences in both total and ionized cations were recorded for some measures between horse groups and different sample types. The most significant differences were recorded between neonatal foals and other groups. These results demonstrate the need to use specific reference intervals for horses of different physiologic status and in specific sample types.  相似文献   
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