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11.
The effect of photodynamic therapy is a function of several variables, including selective retention of the drug in tumor tissue with reduced drug concentration in surrounding normal tissue. A study was designed to determine the pharmacokinetic profile and variability of porfimer sodium in dogs and cats with spontaneous tumors and to thereby determine the optimal timing of its photoactivation in these species. The results of this study indicate that there is marked variability among species in the distribution of porfimer sodium between highly proliferating tissues, which requires careful attention in the design of human and veterinary application of photodynamic therapy with porfimer sodium, as determined in rodent models. 相似文献
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Maria Isabel Ferraz de Oliveira Elsa Lamy Miguel N. Bugalho Margarida Vaz Cristina Pinheiro Manuel Cancela d’Abreu Fernando Capela e Silva Elvira Sales-Baptista 《Agroforestry Systems》2013,87(6):1421-1437
Montados are agro-silvo-pastoral ecosystems, typical of the Southwest Iberian Peninsula, of high socio-economic and conservation importance, where grazing is a dominant activity. Montados are characterized by an open tree canopy of Quercus sp. and a diverse undercover of shrubs and grasslands that constitute the plant food resources for grazing animals. Plant food resources of Montados are highly variable, both spatially and seasonally, in quantity and quality. Reliable and easy to use methods to monitor grazing are necessary to allow proper understanding of foraging strategies of grazing animals and to set sustainable grazing management. We describe the main characteristics of the plant food resources available for grazing animals, striking its variability, and revise the potential of using N-alkanes and saliva proteome methods to assess foraging strategies in Montados. In a scenario of dynamic multiple choices, we discuss the use of n-alkane methodology for the simultaneous estimation of diet composition and voluntary intake and saliva proteome as a mean of increasing the knowledge on diet adjustments. 相似文献
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The influence of field shape, area and surrounding landscape on plant species richness in grazed ex-fields 总被引:1,自引:0,他引:1
Over the past 100 years species-rich semi-natural grasslands have decreased dramatically in Western Europe, where former arable fields (ex-fields) are used instead as pasture. The disappearance of semi-natural grasslands has caused a threat to the biodiversity in agricultural landscapes. Many typical grassland plants are dispersal limited, thus grazed ex-fields can be used to investigate if species spontaneously colonise these new grassland habitats. We examined the relationship between surrounding landscape, field area, shape, distance between edge and centre, and plant species diversity in ex-fields that had been grazed for 15-18 years. The results showed that there were 35% more plant species in fields surrounded by commercial forestry production compared to those surrounded by open agricultural landscape. Area and shape did not influence species richness, although there was increasing number of species in the centre with decreasing distance from the edge. Twenty-five percent of the species where typical grassland species, and ex-fields surrounded by forest had 91% more grassland species compared to those in the open landscape. It is possible to increase grassland plant occurrences by grazing ex-fields surrounded by forest or other grassland remnant habitats, particularly in landscapes where grazed semi-natural grasslands are scarce. 相似文献
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Nutritional Contribution of Biofloc within the Diet of Growout and Broodstock of Litopenaeus vannamei,Determined by Stable Isotopes and Fatty Acids 下载免费PDF全文
Edén Magaña‐Gallegos Rodrigo González‐Zúñiga Gerard Cuzon Miguel Arevalo Eduardo Pacheco Manuel A. J. Valenzuela Gabriela Gaxiola Elisa Chan‐Vivas Korinthia López‐Aguiar Elsa Noreña‐Barroso 《Journal of the World Aquaculture Society》2018,49(5):919-932
The relative contributions of feed sources were determined through the isotopic signal (δ13C and δ15N) and fatty acid profile of feed items, shrimp muscle, and eggs of Litopenaeus vannamei reared in a biofloc system. In the growout phase, the isotope analysis showed the biofloc particle size class ≥250 μm contributed 55–100%; size ≥50 < 250 μm contributed 0–22%; and artificial feed contributed 0–45%. Principal component analysis applied to fatty acid profiles showed that biofloc ≥250 μm and artificial feed were the most important items in shrimp growout. For the egg production, isotope analysis suggested that the most important feed sources according to their relative contributions were polychaetes (0–100%), followed by artemia biomass (0–86%) and semi‐moist feed (0–66%), with lower contributions from squid, mussel, and the muscle of L. vannamei broodstock that had been cultured in biofloc. In terms of fatty acids, the most important items were artemia, polychaetes, and semi‐moist feeds. This work clarified the importance of feed sources for shrimp during culture in biofloc systems and during reproduction. Analysis of stable isotopes and fatty acids can be successfully used to trace the assimilation of nutrients during the nutrition of shrimp. 相似文献
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The existence of facultative parthenogenesis in mealybugs has been reported by different authors and questioned by others
in relation to certain species. We tested the hypothesis of facultative parthenogenesis in relation to three mealybug species,
Planococcus citri (Risso), Pseudococcus calceolariae (Maskell) and Pseudococcus viburni (Signoret). The results suggest that these mealybug species are obligate amphimictic. 相似文献
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Elsa Beltran Alberta De Stefani Jennifer Stewart Luisa De Risio Victoria Johnson 《Veterinary ophthalmology》2010,13(3):184-189
Mast cell tumors are found in most organs and tissues with variable biologic behavior in dogs. This case illustrates the clinical and magnetic resonance imaging (MRI) findings in a dog with disseminated mast cell tumor infiltrating the sphenoid bones. A 6‐year‐old male neutered Greyhound presented with a 3‐day history of acute onset of blindness. General physical examination was normal. Neurological examination revealed mildly disorientated mental status, absent menace response in both eyes, bilaterally decreased vestibulo–oculocephalic reflexes and absent direct and consensual pupillary light reflex in both eyes. An electroretinogram indicated normal retinal function in both eyes. A lesion involving the middle and rostral cranial fossa was suspected. Hematology and serum biochemistry were normal except decreased urea (1.2 mmol/L). MRI of the head revealed heterogeneous signal intensity of the sphenoid bones on T2‐weighted images and loss of their normal internal architecture. Cerebrospinal fluid analysis was normal. Abdominal ultrasound revealed hepatosplenomegaly and mesenteric lymphadenopathy. Fine needle aspirates were taken from the jejunal lymph nodes and the spleen. Results were consistent with disseminated mast cell tumor. The owner declined any treatment and the dog was euthanatized. Postmortem examination confirmed disseminated mast cell tumor affecting multiple organs, including the sphenoid bones. To our knowledge, this is the first case describing MRI features of disseminated mast cell tumor affecting the sphenoid bones and causing acute onset of blindness in a dog. 相似文献
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Fernández E Toledo JR Chiong M Parra F Rodríguez E Montero C Méndez L Capucci L Farnós O 《Veterinary immunology and immunopathology》2011,142(3-4):179-188
Rabbit hemorrhagic disease virus (RHDV) is the etiological agent of a lethal and contagious disease of rabbits that remains as a serious problem worldwide. As this virus does not replicate in cell culture systems, the capsid protein gene has been expressed in heterologous hosts or inserted in replication-competent viruses in order to obtain non-conventional RHDV vaccines. However, due to technological or safety issues, current RHDV vaccines are still prepared from organs of infected rabbits. In this work, two human type 5 derived replication-defective adenoviruses encoding the rabbit hemorrhagic disease virus VP60 capsid protein were constructed. The recombinant protein was expressed as a multimer in mouse and rabbit cell lines at levels that ranged from approximately 120 to 160 mg/L of culture. Mice intravenously or subcutaneously inoculated with a single 10(8) gene transfer units (GTU) dose of the AdVP60 vector (designed for VP60 intracellular expression) seroconverted at days 7 and 14 post-immunization, respectively. This vector generated a stronger response than that obtained with a second vector (AdVP60sec) designed for VP60 secretion. Rabbits were then immunized by parenteral or mucosal routes with a single 10(9)GTU dose of the AdVP60 and the antibody response was evaluated using a competition ELISA specific for RHDV or RHDVa. Protective hemagglutination inhibition (HI) titers were also promptly detected and IgG antibodies corresponding with inhibition percentages over 85% persisted up to one year in all rabbits, independently of the immunization route employed. These levels were similar to those elicited with inactivated RHDV or with VP60 obtained from yeast or insect cells. IgA specific antibodies were only found in saliva of rabbits immunized by intranasal instillation. The feasibility of VP60 production and vaccination of rabbits with replication-defective adenoviral vectors was demonstrated. 相似文献