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21.
The aim of this study was to evaluate the prevalence of chronic gastritis in pet dogs, to determine the histopathologic changes of gastric mucosa and, to determine its relationship with canine gastric Helicobacter infection. Sixty percent (n = 18), 27% (n = 8) and 13% (n = 4) of the examined stomachs showed normal, congested and erosive gastric mucosa respectively. Histopathologic examination was confirmed the presence of chronic gastritis in 40% of dogs (n = 12). Lymphocytic-plasmacytic gastritis was the most common type of chronic gastritis. Gastric Helicobacter was detected in cytological examination of 26 out of 30 dogs (86.6%) but in the PCR analysis, 93% of gastric samples were positive for GHLO. There was no significant relation between the presence of Helicobacters and chronic gastritis (p>0.05). Follicular gastritis was detected in 12 cases (40%) and there was also no significant correlation between its presence and GHLO's infection (p>0.05). In conclusion, chronic gastritis can be considered as a prevalent disease especially in dogs. Nutritional and environmental factors as well as individual immune response may have role in induction of chronic gastritis, but the clinical significance of these histopathologic changes should be evaluated.  相似文献   
22.
A 5‐week study was performed to evaluate the effect of spoilage date extract (SDE) as the biofloc carbon source on Litopenaeus vannamei (5.4 ± 0.3 g) performance. The two levels of dietary protein (15% and 25% crude protein) and two carbohydrate sources (molasses‐M and SDE‐P) were tested including: M15, M25, P15 and P25. The minimum (0.2 ± 0.0 mg/L) and the maximum (0.5 ± 0.0 mg/L) of total ammonia nitrogen were observed in the P15 and M25 groups respectively. The highest protein efficiency ratio (6.1 ± 0.3) and protein productive value (112.3 ± 5.8%) were found in the P15 group (p < 0.05). No significant difference was found between biofloc treatments in the expression of cathepsin L gene in hepatopancreas (p > 0.05). The number of total haemocyte count (THC), semigranular cells (SGC) and granular cells (GC) of shrimp in SDE‐based biofloc treatments was relatively higher than those in molasses‐based biofloc treatments. Following the white spot syndrome virus (WSSV) challenge, a significant decrease in THC, SGC, GC and hyaline cell values was observed in all treatments (p = 0.001). Plasma biochemical parameters were significantly influenced by dietary protein levels, biofloc carbon sources as well as WSSV challenge test. In conclusion, SDE successfully could be used as an alternative carbon source for establishing a biofloc system in L. vannamei production.  相似文献   
23.
[目的]为枣实蝇引诱剂的研发提供理论依据。[方法]从枣实蝇行为学研究入手,以“Y”型嗅觉仪分别测试了枣实蝇对红枣和杏两种寄主植物不同新鲜器官的选择行为。[结果]表明,不同性别的枣实蝇成虫对寄主植物枣和杏不同器官的选择性表现出一定差异。雌虫对枣果的选择性比叶片和花的要强(P<0.05),对枣果、枣花、叶片三者的选择率分别为35%、25%、22%;从枣果不同发育期(青果期、半红期、全红期)的选择性来看,雌虫对半红期枣果的选择性最强,选择率为38%,青果次之,为35%。而雄虫对枣花的选择性较强,选择率为38%,半红期枣果次之,为32%。枣实蝇对杏树不同器官的选择性来看,对果实的选择性比叶片的选择性要强(P<0.05),从杏果(青果、熟果)不同发育期的选择性来看,雌虫对青果的选择性最强,选择率为30%,熟果次之,为28%。雄虫对熟果的选择性较强,选择率为28%,与青果、叶片有显著差异(P<0.05)。[结论]同一性别不同生理状态的成虫对寄主植物不同器官的选择性表现出一定差异,性成熟的成虫比未性成熟的成虫对寄主植物的选择性要强。性成熟的枣实蝇雌成虫对半红期枣果的趋性强于枣花与叶片  相似文献   
24.
The interaction between particle size and resin content is one of the most important structural parameters that can influence the accuracy of predictions about wood-composite properties. We developed three kinds of equation (linear, quadratic, and exponential) for each mechanical property of particleboard based on slenderness ratio and resin content at a constant density (0.7g cm -3 ). Results from SHAZAM software (version 9) suggested that the quadratic function was not significant, but the linear and exponential functions were significant. The interaction between particle size and resin content was analyzed by Maple 9 software. The results indicated that an exponential function can better describe the simultaneous effect of slenderness and resin content than a linear equation. Under constant resin content, particles with higher slenderness ratios increased more in modulus of rupture (MOR) and modulus of elasticity (MOE) than did particles with lower slenderness ratios. Edge withdrawal resistance (SWRe) values did not increase with increasing slenderness ratio.  相似文献   
25.
【目的】研究新疆盐碱环境中耐盐植物白刺的根际土壤和叶片内生微生物群落的结构丰富度和多样性。【方法】运用Novaseq测序平台对白刺根际土壤和叶片进行16SrDNA-V4区和ITS1区测序。经FLASH进行拼接,经过Qiim过滤叶绿体和线粒体序列,得到的序列在97%的序列相似性水平上聚类成为操作分类单元(OTUs)。对序列数据进行生物信息学分析,评价物种的Chao1指数、shannon指数以及Alpha多样性。【结果】白刺根际土壤细菌优势菌群为放线菌门(Actinobacteria)、变形菌门(Proteobacteria)、芽单胞菌门(Gemmatimonadetes);真菌优势菌群为子囊菌门(Ascomycota)。叶片内生细菌优势菌群为蓝细菌门(Cyanobacteria)和放线菌门(Actinobacteria);真菌优势菌群为子囊菌门(Ascomycota),白刺不同部位的微生物菌群数量和多样性有显著差异(P<0.05),白刺各样地之间微生物群落构成差异明显。【结论】白刺不同部位微生物群落的丰富度和多样性分布。  相似文献   
26.
Development plans are mainly responsible for population changes and the conversion of forest and rangelands into agricultural lands and human settlements. Qualitative and quantitative analysis of population and land use changes are necessary to assess the impacts of change on hydrological processes. However, such important issues have been less considered worldwide particularly in developing countries. Therefore, we selected the Shazand Watershed (1740 km2) because of rapid industrialization to track the effects of land use and population changes on streamflow and sediment yield. The data were collected from statistical yearbooks and satellite imageries from 1973 to 2008. All available measurements on discharge and suspended sediment concentration at the Pole doab hydrological station were also collected. The study was conducted for the whole period, as well as the pre‐1991 and post‐1991 as a basis for the economic development growth in the region. We found that the land use and population changes have occurred in the Shazand Watershed, especially in the vicinity of industrial zones. The results showed that the cities, industrial zones, roads, and bare lands quickly increased from 58 · 8 to 134 · 3 km2 during post‐1991. The flow durations, sediment rating curves and trend analyses indicated distinct variations in the relationship between streamflow and sediment and also caused changes within different periods. Based on the results, the mean annual flow and sediment yield in post industrialization (1991–2008) were respectively 0 · 84 and 1 · 19 times of those for pre‐industrialization period and the annual sediment yield increased from 25,000 to 29,850 Mg. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
27.
利用水稻功能基因SSR标记鉴定水稻种质资源   总被引:36,自引:6,他引:36  
 利用 16对水稻功能基因的SSR引物研究了 2 3份世界 5个国家不同来源的水稻种质资源的遗传多样性 ,共检测出 78个等位基因变异 ,每对引物可检测 2~ 10个等位基因变异 ,平均为 5 .2个 ,品种间遗传相似系数在0 .13~ 0 .6 4之间。UPGMA聚类分析表明 ,在相似系数 0 .13处可以将材料分为 2大类 ,来自巴西、日本和中国的粳稻全部聚为第Ⅰ类 ,巴西陆稻和原产科特迪瓦的陆稻聚在第Ⅰ类的第三小群 ;第Ⅱ类全为籼稻 ,来源于巴基斯坦的籼稻和 1个来源于韩国的籼稻分布在第Ⅱ类 ,说明水稻功能基因在不同亚种、不同产地来源和不同生态类型的水稻之间存在差异 ,也进一步证实水稻功能基因的SSR标记是研究水稻种质资源分类、地理分布、生态类型和系谱分析的有效工具。  相似文献   
28.
Sesquiterpenes have antifungal, antibacterial, and anesthetic properties. It is also thought that they prevent migraines and can be used as antibiotics and to treat malaria, but there are very few in-depth testing results available to support these claims. Nanocapsules coated by medicinal plants have many applications in drug manufacturing. Medicinal plants can be loaded on nanocapsules with the polyester triblock copolymer polyethylene glycol-polybutylene adipate-polyethylene glycol (PEG-PBA-PEG) as the shell and olive oil as the core by a process known as the polymer deposition solvent evaporation method. It has been shown that the size of nanocapsules depends on a variety of factors, such as the ratio of polymer to oil, concentration of polymers, and concentration of plant extract. In this research we attempted to prepare nanocapsules by emulsification of a mixture of onopordopicrin extracted from Onopordon leptolepis DC., polymer, acetone, and olive oil in aqueous phase without using surfactant. The nanocapsules were characterized by scanning electron microscopy and zeta potential sizer.  相似文献   
29.
Journal of Soils and Sediments - Understanding the mechanisms of interaction between humic acids (HAs) and metal ions in soil media is essential for integrated environmental and agricultural...  相似文献   
30.
This study is designed to assess the application of neural networks in comparison to the Kaplan-Meier and Cox proportional hazards model in the survival analysis. Three hundred thirty gastric cancer patients admitted to and surgically treated were assessed and their post-surgical survival was determined. The observed baseline survival was determined with the three methods of Kaplan-Meier product limit estimator, Cox and the neural network and results were compared. Then the binary independent variables were entered into the model. Data were randomly divided into two groups of 165 each to test the models and assess the reproducibility. The Chi-square test and the multiple logistic model were used to ensure the groups were similar and the data was divided randomly. To compare subgroups, we used the log-rank test. In the next step, the probability of survival in different periods was computed based on the training group data using the Cox proportional hazards and a neural network and estimating Cox coefficient values and neural network weights (with 3 nodes in hidden layer). Results were used for predictions in the test group data and these predictions were compared using the Kaplan-Meier product limit estimator as the gold standard. Friedman and Kruskal-Wallis tests were used for comparisons as well. All statistical analyses were performed using SPSS version 11.5, Matlab version 7.2, Statistica version 6.0 and S_PLUS 2000. The significance level was considered 5% (alpha = 0.05). The three methods used showed no significance difference in base survival probabilities. Overall, there was no significant difference among the survival probabilities or the trend of changes in survival probabilities calculated with the three methods, but the 4 year (48th month) and 4.5 year (54th month) survival rates were significantly different with Cox compared to standard and estimated probabilities in the neural network (p < 0.05). Kaplan-Meier and Cox showed almost similar results for the baseline survival probabilities, but results with the neural network were different: higher probabilities up to the 4th year, then comparable with the other two methods. Estimates from Cox proportional hazards and the neural network with three nodes in hidden layer were compared with the estimate from the Kaplan-Meier estimator as the gold standard. Neither comparison showed statistically significant differences. The standard error ratio of the two estimate groups by Cox and the neural network to Kaplan-Meier were no significant differences, it indicated that the neural network was more accurate. Although we do not suggest neural network methods to estimate the baseline survival probability, it seems these models is more accurately estimated as compared with the Cox proportional hazards, especially with today's advanced computer sciences that allow complex calculations. These methods are preferable because they lack the limitations of conventional models and obviate the need for unnecessary assumptions including those related to the proportionality of hazards and linearity.  相似文献   
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