首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   77篇
  免费   5篇
林业   8篇
农学   1篇
基础科学   1篇
  16篇
综合类   7篇
农作物   1篇
水产渔业   3篇
畜牧兽医   41篇
园艺   4篇
  2023年   1篇
  2021年   6篇
  2020年   4篇
  2019年   3篇
  2018年   2篇
  2016年   5篇
  2015年   2篇
  2014年   1篇
  2013年   4篇
  2012年   8篇
  2011年   4篇
  2010年   6篇
  2009年   6篇
  2008年   4篇
  2007年   9篇
  2006年   4篇
  2005年   5篇
  2004年   1篇
  2003年   3篇
  2002年   3篇
  2000年   1篇
排序方式: 共有82条查询结果,搜索用时 15 毫秒
11.
Three major virgin olive oil varieties (Dritta, Leccino, and Coratina) extracted by a modern centrifugation system aided with a new plant enzyme preparation (having prevalently pectolytic activity) were characterized. These oils showed a clearly enhanced quality standard, owing to higher levels of some important minor components (phenolics, volatiles, tocopherols, carotenes, and chlorophylls) and to frequently lower concentrations of oxidized triglycerides and diglycerides. The oils were therefore characterized by lower susceptibility to oxidation and longer shelf life, and their flavor, aroma, and color features appeared to be significantly improved. The saponifiable fraction was practically not affected as the enzymatic effects involved only the membranes of the oil droplets, where the nonglyceridic compounds are essentially located.  相似文献   
12.
Common fig (Ficus carica L.) is one of the most ancient domesticated species, originated, supposedly in Arabia, from where it diffused to the Middle East and Asia, and to the Mediterranean basin, where it greatly diffused. More than 600 fig varieties have been described, but it is conceivable that this number is underestimated. Along all the Italian territory, there is a rich germplasm of fig composed of a large number of varieties (approximately 300) of very not well defined origin. Effectively, during several centuries of cultivation and propagation by seed, a large number of genotypes appeared and were selected, leading to the generation of an uncountable number of genotypes, different in numerous traits, particularly in those related to leaves and fruits features. Unfortunately, the extensive existing fig genetic patrimony is facing genetic erosion; for this reason, it is extremely important to study and valorised it, in order to preserve the remaining biodiversity. The purpose of this study was to genetically characterize, with nSSR markers, 79 fig accessions, collected in several areas in Italy. The set of chosen markers resulted highly polymorphic, and allowed the characterization of all the studied accessions. Data were analysed by cluster analysis, and the results demonstrated a great genetic variability within the population. The nSSR used, moreover, allowed us to identify all accessions and to recognised possible homonyms and synonyms, and cases of intravarietal clones.  相似文献   
13.
Computed tomographic images of the neck, thorax and abdomen in four healthy adult rabbits were obtained with a conventional CT using a slice-thickness of 5 mm. CT images were obtained with the animals positioned in sternal recumbency on a removable plastic support directly laying on the CT-table. At the end of the CT session, each rabbit was euthanized and, while carefully maintaining the same position on the plastic support, the animal was moved into a −20 °C freezer until completely frozen. Each cadaver was then sectioned at 10 mm slices, with the first section starting at the tip of the nose, respecting the imaging protocol. The frozen sections were cleaned and then photographed on each side. Anatomic structures were identified and labeled first on each side of the frozen section and then on the corresponding CT image with the aid of the available literature. Results from our study provide an atlas of normal cross-sectional gross and CT anatomy of the rabbit neck, thorax and abdomen, useful in the interpretation of any cross-sectional imaging modality in this species.  相似文献   
14.
BACKGROUND: Artifactual changes in blood may occur as a consequence of delayed analysis and may complicate interpretation of CBC data. OBJECTIVE: The aim of this study was to characterize artifactual changes in canine blood, due to storage, using the ADVIA 120 hematology analyzer. METHODS: Blood samples were collected into EDTA from 5 clinically healthy dogs. Within 1 hour after blood sample collection and at 12, 24, 36 and 48 hours after storage of the samples at either 4 degrees C or room temperature (approximately 24 degrees C), a CBC was done using the ADVIA 120 and multispecies software. A linear mixed model was used to statistically evaluate significant differences in values over time, compared with initial values. RESULTS: The HCT and MCV were increased significantly after 12 hours of collection at both 4 degrees C and 24 degrees C, and continued to increase through 48 hours. The MCHC initially decreased significantly at 12-24 hours and then continued to decrease through 48 hours at both temperatures. Changes in HCT, MCV, and MCHC were greater at 24 degrees C than at 4 degrees C at all time points. A significant increase in MPV and a decrease in mean platelet component concentration were observed at all time points at 24 degrees C. Samples stored at 24 degrees C for 48 hours had significantly higher percentages of normocytic-hypochromic RBCs, and macrocytic-normochromic RBCs, and lower platelet and total WBC counts. CONCLUSIONS: Delayed analysis of canine blood samples produces artifactual changes in CBC results, mainly in RBC morphology and platelet parameters, that are readily detected using the ADVIA 120. Refrigeration of specimens, even after 24 hours of storage at room temperature, is recommended to improve the accuracy of CBC results for canine blood samples.  相似文献   
15.
Crop yield forecasting has progressed clearly in the past years, mainly due to the growing demand for modelling. In the present research, considering the Mediterranean vocation for the olive cultivation, olive yield forecasting modelling was analysed, to understand the principal relationships between olive tree production and climate features in a large southern Italy area. The simulation of olive yield has practical application in different price formation activities: in management of cropping systems, formation of stocks, commercialization, making of agricultural policies and zoning. Both meteorological and biological variables were considered, pollen indexes were constructed from daily pollen concentrations evaluated by use of aerobiological methodology. The monitored pollen quantities should be considered as a Proxy variable of the olive orchards located around the volumetric pollen traps, even if the final harvest could be highly dependent on local summer meteorological conditions. The model carried out by use of Panel data analysis has demonstrated a great interpretative capacity, considering contemporary meteorological and biological variables (pollen monitored with volumetric traps). The aggregation of historical data (1999–2008) with cross-section data (10 different pollen monitoring stations) permitted to investigate the variability information related to temporal and geographical dimensions. The entire volume of pollen grains emitted during flowering was redundant to investigate the future fruit formation while the specific and concentrated mass of pollen grains during the days before full flowering was related positively with the final production. The statistical technique utilized permitted to obtain interpretative results common to different geographical areas and not limited by local meteorological conditions.  相似文献   
16.
This work investigated the effects of land cover and land-use change (LUC) on the ability of a soil to store carbon (C) and reduce carbon dioxide (CO2) emissions, in a Mediterranean area. Using a paired-site approach, we estimated the effect of land-cover change on the C stock from 1972 to 2008 in a natural reserve (Grotta di Santa Ninfa) in western Sicily. We selected 15 paired sites representative of five LUCs. We studied the effect of land use on soil organic C (SOC) content in bulk soil and in different particle-size fractions (2000-1000 μm, 1000-500 μm, 500-250 μm, 250-63 μm, 63-25 μm, and < 25 μm). Laboratory incubation of the soil samples was conducted to measure CO2 evolution in bulk soil collected at two different depths from each paired site. We found that the conversion of natural vegetation to orchards (vineyards and olive groves) resulted in SOC decreases ranging from 27% to 50%. The conversion from vineyards to arable land led to a 9% decrease in SOC, whereas the opposite caused a 105% gain. When arable land was replaced by Eucalyptus afforestation, a 40% increase in SOC was observed. SOC decline occurred mainly in coarser soil fractions, whereas the finest fractions were not influenced by land use. We calculated an overall SOC reduction of 63% in the study area, corresponding to a 58 Mg ha− 1 SOC loss in less than 30 years. Our results indicate that land-use conversion, vegetation type, and management practices that control the biogeochemical and physical properties of soil could help reduce CO2 emissions and sequester SOC.  相似文献   
17.
The main bacterial pathogens of cultivated mushroom as well as mushroom-associated bacteria, which were isolated from Agaricus bisporus, Pleurotus ostreatus and Pleurotus eryngii mushroom niches, were evaluated for the production of N-acyl-L-homoserine lactones (AHLs) by using four bioreporters. Furthermore, identification of AHLs by LC-ESI-FTICR MS was performed on culture filtrates of selected pathogens and mushroom-associated bacteria strains, which resulted in inducing at least one of the four bioreporters. Strains of Burkolderia gladioli pv. agariciola, Pseudomonas agarici and Pseudomonas gingeri, but not those of Pseudomonas tolaasii and Pseudomonas reactans, produced an array of AHLs depending on the strain. This is the first report of AHL production by mushroom bacterial pathogens. Forty-four of 236 bacterial isolates obtained from different niches of cultivated mushrooms, in part identified by the Biolog identification system, were demonstrated to produce AHLs. Among them, seven mushroom-associated bacterial species were for the first time demonstrated to produce the above signal molecules. In the culture filtrates of a certain number of isolates/strains the AHL-hydrolyzed forms were also present. The minimal signal inducing concentration (MSIC) of selected pure AHLs was also determined for the four bioreporters used in this study.  相似文献   
18.
19.
The effect of finishing extensive farming period, to reduce fat content and manipulate the fatty acid profile of fish muscle, was evaluated in rainbow trout. Fish were stocked in an artificial lake, in which fish were fed only on naturally available nutrients with no supply of artificial feed, for different lengths of time from 0 to 120 days. No weight loss was noted during the whole finishing period while total length increased from 228±7 to 269±3 mm and the condition factor decreased from 1.41±0.04 to 0.89±0.02. The total fat content of the fillets decreased considerably from 4.7±0.6% at the beginning to 2.4±0.4% and 0.7±0.2% after 45 and 120 days respectively. Fillet fatty acid composition was affected by the time of stocking in the extensive farm. In contrast to the reduction in C18:1n‐9, C18:2n‐6, total monounsaturated fatty acid and total n‐6 percent values, an increase in the C20:5n‐3, C22:6n‐3, total polyunsaturated fatty acid and total n‐3 percent values was observed. It was shown that while other finishing strategies for salmonids have some disadvantages, the extensive culture system seems to be a potentially useful tool for increasing the general quality of the end product.  相似文献   
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号