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91.
The aim of the present study was to evaluate the effect of the phosphates on tuna meat pH, and water-to-protein ratio. Tuna fillets were soaked in cold (5 °C) tripolyphosphate solution (STPP) and blend phosphate (CARNAL® 961) at 3, 5 and 10% for 30, 60 and 120 min. The control group was represented by cold distilled water. After soaking, the samples were drained, weighed, frozen, stored (-35 °C, for 15 days), thawed, drained, and grilled. After each step, samples were withdrawn for the following analysis: pH, phosphate (as P2O5), moisture and protein. A gradual increase in pH and residual phosphate was observed, which remained below the limits established by national (for pH) and international (for phosphate) legislation. A moderate positive correlation between pH and phosphate values was observed. An increase in moisture content and the water-to-protein ratio were observed, and still below to the legislation limit (i.e., 6.0). We suggest a critical review and possible changes in the parameters which are used as indicators of abusive use of the phosphate additive in seafood to combat the economic fraud in the frozen seafood products. It should be emphasized that these suggestions should be the focus of the collaborative study for its validation.  相似文献   
92.
Tropical Animal Health and Production - The aim of this study was to replace fetal bovine serum (FBS) with platelet-rich plasma (PRP) for in vitro production of bovine embryos. The maturation media...  相似文献   
93.
In sagebrush rangelands perennial bunchgrasses are typically seeded in fall and a high proportion of planted seeds germinate prior to winter onset but fail to emerge in spring. Our objectives were to evaluate freezing tolerance of germinated but nonemergent bluebunch wheatgrass seeds under laboratory conditions. We used data from a 2-yr pilot study to determine overwinter freezing temperature and duration for soils in southeastern Oregon. We then conducted two experiments to assess freezing tolerance. In experiment 1, bluebunch wheatgrass seeds were planted in control pots and compared to seeds planted at early, mid, or late postgermination stages. Pots from each treatment were placed in a grow room maintained at 12 h 40 min light/11 h 20 min dark photoperiod, with a constant temperature of 22°C for 30 d either immediately or following a 30-d freeze. In experiment 2, germinated bluebunch wheatgrass seeds were planted in pots that were left nonfrozen or were frozen for a specified duration prior to a 30-d period in the grow room. Emergence density and tillers · seedling?1 were quantified for both experiments. The number of days per year for freezing soil conditions in the pilot study ranged yearly from 25 to 51; maximum duration of continuous freezing was 16.5 and 11.2 d. Freezing reduced or eliminated seedling emergence at all postgermination stages (P < 0.001) and tiller density was reduced by at least 50% (P < 0.001). Maximum reduction in seedling density (P < 0.001) was realized within 4 d of initiation of freezing and tillers · seedling?1 were reduced 30–70% with > 6 d of freezing (P = 0.001). Our data indicate that freezing-associated mortality of germinated but nonemergent bluebunch wheatgrass seedlings can be extremely high and suggest that management practices to reduce prewinter germination of seeds could improve subsequent emergence and seeding success.  相似文献   
94.
Phylogeny is an evolutionary reconstruction of the past relationships of DNA or protein sequences and it can further be used as a tool to assess population structuring, genetic diversity and biogeographic patterns. In the microbial world, the concept that everything is everywhere is widely accepted. However, it is much debated whether microbes are easily dispersed globally or whether they, like many macro-organisms, have historical biogeographies. Biogeography can be defined as the science that documents the spatial and temporal distribution of a given taxa in the environment at local, regional and continental scales. Speciation, extinction and dispersal are proposed to explain the generation of biogeographic patterns. Cyanobacteria are a diverse group of microorganisms that inhabit a wide range of ecological niches and are well known for their toxic secondary metabolite production. Knowledge of the evolution and dispersal of these microorganisms is still limited, and further research to understand such topics is imperative. Here, we provide a compilation of the most relevant information regarding these issues to better understand the present state of the art as a platform for future studies, and we highlight examples of both phylogenetic and biogeographic studies in non-symbiotic cyanobacteria and cyanotoxins.  相似文献   
95.
The volatile composition of the essential oils from leaves and roots of Eupatorium betonicaeforme (D.C.) Baker was analyzed by GC-MS. A total of 12 compounds were identified. beta-Caryophyllene (12.4-41.7%), alpha-humulene (11.7-14.6%), gamma-muurolene (10.4-19.0%), bicyclogermacrene (15.0-17.5%), 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%), and 2-senecioyl-4-vinylphenol (8.5-41.0%) were the most prominent constituents. The former two compounds were isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti larvae survival. The results obtained show that the essential oil from roots and 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%) could be considered as natural larvicidal agents.  相似文献   
96.
We consider monthly temperature data collected over a period of 16 years at 24 stations in the estuarine wetlands of the Elkhorn Slough watershed, located in the Monterey Bay area in Central California, USA. Our goal is to develop a statistical model in order to separate the seasonal cycle, short-term fluctuations, and long-term trends, while accounting for the spatial variability of these features. In the model, each station has a specific, time-invariant mixture of two seasonal patterns, to encompass the spatial variability of oceanic influence. Likewise, trends are modeled as local mixtures of two patterns, to include the spatial variability of long-term temperature change. Finally, all stations share a common baseline, whose temporal variability is linearly dependent on a variable that summarizes several atmospheric measurements. We use a Bayesian approach with a purposely developed Markov chain Monte Carlo method to explore the posterior distribution of the parameters. We find that the seasonal cycles have changed in time, that neighboring stations can have substantially different behaviors, and that most stations show significant warming trends.  相似文献   
97.
An agrarian sensorial system based on temperature, moisture, and all solid-state ion-selective potentiometric sensors was developed with the objective of monitoring the behavior of H+ and Ca2+ ions in soil and in real conditions, contributing with a new tool that tries to complement the current precision agriculture technology. The evaluation of the sensorial system to pH monitoring presented a good correlation between the results obtained by the system and the standard methodology, allowing us to notice the soil buffer capacity at different soil depths. With regard to calcium, the sensor system also presented an agreement between its results and those obtained by flame atomic absorption spectrometry, using a calibration model based on multiple linear regressions that allows the correct determination of Ca2+ concentrations in soil depths where the relative moisture is different. In this way, using well-known potentiometric sensors in a complex, discontinued, and heterogeneous matrix, such as soil, the sensorial system proved to be a useful task for agrochemical field applications.  相似文献   
98.
Life expectancy of crab‐eating foxes in captivity is approximately 11 years, which favours the development of diseases including orthopaedic disorders. However, to understand disorders that may affect these animals, it is worth determining a normal range of measurements. Therefore, this study aimed to evaluate radiographic measurements of joint angles of the hindlimbs and the ratio of patellar ligament length to patellar length in healthy crab‐eating foxes. Fifteen captive crab‐eating foxes (Cerdocyon thous), eight males and seven females, aged more than 1 year old, weighing 5.5–7.9 kg were used. Anatomic and mechanical femoral joint angles were assessed in ventrodorsal radiographic views, and mediolateral views were taken to measure patellar ligament length and patellar length, and the tibial plateau angle. The right and left hindlimbs were evaluated. All measurements were conducted in triplicate by the same investigator. No statistically significant differences were observed between sides in the radiographic measurements. The anatomic lateral proximal femoral angle and the anatomic lateral distal femoral angle recorded mean values of 95.43° and 92.75°, respectively. The mechanical lateral proximal femoral angle and the mechanical lateral distal femoral angle recorded mean values of 93.39° and 96.75°, respectively. Inclination angles measured according to the Tomlinson, Hauptman A and Hauptman B methods were 133.80°, 147.32° and 128.63°, respectively. The tibial plateau recorded 18.77°, and the ratio of the patellar ligament length to the patellar length was 1.99. In conclusion, the collected data are important to characterize the normal values of crab‐eating fox limbs.  相似文献   
99.
A 6‐year‐old female neutered European Shorthair cat was presented with a 2‐day history of lethargy and hyporexia. On physical examination, the cat was slightly depressed and had a 2.5 cm nodule in the left 3rd mammary gland. The hemogram revealed mild leukocytosis with mature neutrophilia and moderate thrombocytopenia. On blood smear evaluation, rare pleomorphic cells, possibly of epithelial origin, were observed mainly at the feathered edge. The animal died about 12 hours after presentation, and a necropsy was performed. On histopathology, the mammary nodule was diagnosed as a tubulopapillary adenocarcinoma with vascular invasion and widespread metastases. Immunocytochemical tests for cytokeratins (AE1/AE3) confirmed the epithelial phenotype of the neoplastic cells observed on the blood smear. The present report describes a feline mammary carcinoma with widespread metastases and the presence of malignant epithelial cells in the peripheral blood referred to as carcinocythemia. This condition has been previously described in people and dogs. To the author's knowledge, this is the first reported case of feline carcinocythemia. As in other species, the phenomenon was associated with a terminal phase of systemic malignancy.  相似文献   
100.
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