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31.
Journal of Plant Diseases and Protection - In Mexico, okra (Abelmoschus esculentus L.) is grown mainly for export, but its production is affected by various pests and diseases. Plants with mosaic...  相似文献   
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This study was to characterise the undigested nutrients present along the gastrointestinal tract of birds offered common wheat-or maize-based diets, with the goal of optimising utilisation of enzymes to enhance digestive efficiency. Wheat-and maize-based diets were offered to 240 mixed-sex broilers(10birds/pen; n = 12) from 1 to 35 d post-hatch. Digestibility of dry matter, starch, crude protein and nonstarch polysaccharides(NSP) were measured in the crop, gizzard, duodenum, jejunum, ileum, caec...  相似文献   
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Shade is a mechanism to reduce heat load providing cattle with an environment supportive of their welfare needs. Although heat stress has been extensively reviewed, researched, and addressed in dairy production systems, it has not been investigated in the same manner in the beef cattle supply chain. Like all animals, beef cattle are susceptible to heat stress if they are unable to dissipate heat during times of elevated ambient temperatures. There are many factors that impact heat stress susceptibility in beef cattle throughout the different supply chain sectors, many of which relate to the production system, that is, availability of shade, microclimate of environment, and nutrition management. The results from studies evaluating the effects of shade on production and welfare are difficult to compare due to variation in structural design, construction materials used, height, shape, and area of shade provided. Additionally, depending on operation location, shade may or may not be beneficial during all times of the year, which can influence the decision to make shade a permanent part of management systems. Shade has been shown to lessen the physiologic response of cattle to heat stress. Shaded cattle exhibit lower respiration rates, body temperatures, and panting scores compared with unshaded cattle in weather that increases the risk of heat stress. Results from studies investigating the provision of shade indicate that cattle seek shade in hot weather. The impact of shade on behavioral patterns is inconsistent in the current body of research, with some studies indicating that shade provision impacts behavior and other studies reporting no difference between shaded and unshaded groups. Analysis of performance and carcass characteristics across feedlot studies demonstrated that shaded cattle had increased ADG, improved feed efficiency, HCW, and dressing percentage when compared with cattle without shade. Despite the documented benefits of shade, current industry statistics, although severely limited in scope, indicate low shade implementation rates in feedlots and data in other supply chain sectors do not exist. Industry guidelines and third-party on-farm certification programs articulate the critical need for protection from extreme weather but are not consistent in providing specific recommendations and requirements. Future efforts should include: updated economic analyses of cost vs. benefit of shade implementation, exploration of producer perspectives and needs relative to shade, consideration of shade impacts in the cow–calf and slaughter plant segments of the supply chain, and integration of indicators of affective (mental) state and preference in research studies to enhance the holistic assessment of cattle welfare.  相似文献   
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高危型HPV感染致宫颈病变的发病率越来越高,张晓甦教授认为本病病位在冲任二脉,连及肝经;病因为湿、热、毒;治疗上主要以清热利湿、解毒散瘀为主,制定基本方清带解毒汤,根据湿热毒的偏盛,随证加减用药。内服配合外敷,临床疗效甚佳。  相似文献   
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Subsistence landholders in southern Togo are interested in planting teak on their land for income generation. The purpose of this study was to determine how smallholder farmers could allocate land among maize, cassava, and teak plantings in order to optimize financial returns. A linear programming model was developed to calculate the optimal land allocation for maize, cassava, and teak. The model was solved for five farmer types using 15- and 30-yr teak rotations, with timber priced at alternative market and government market prices, and with discount (real interest) rates of 8, 11, and 15%. The analyses indicate that growing teak is profitable for most smallholders if grown on a 15-yr rotation and sold on the alternative market. For Land Rich-Labor Poor farmers, teak is profitable under all regimes.  相似文献   
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Aquatic foods are rich in micronutrients essential to human health, and fisheries and aquaculture are increasingly recognized for their capacity to contribute to reducing global micronutrient deficiencies and diet-based health risks. Whether fisheries and aquaculture sector and public health nutrition policies align to meet this goal, however, is unclear. Do fisheries and aquaculture policies have explicit nutrition and public health objectives? Do public health nutrition policies recognize the contribution of aquatic foods? Using content analysis, we assessed the alignment of objectives in national fisheries and public health nutrition policies. We further determined conditions associated with varying levels of cohesion among policies in these sectors or domains. We found that 77 of 158 national fisheries policies identified nutrition as a key objective in the sector, and 68 of 165 public health nutrition policies identified the importance of fish and shellfish consumption as key objectives. More recent policies were associated with improved coherence among sectors. International organization presence in policy development was also associated with greater coherence. Countries with higher overweight prevalence had fisheries and public health nutrition policies that were not aligned. There has been a promising recent trend for improved alignment of objectives between fisheries and public health nutrition policies, but more targeted and systematic policy approaches are needed to realize the potential contribution of nutrient-rich fish and shellfish to healthier food systems.  相似文献   
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Three LAMP (loop-mediated isothermal DNA amplification) assays were applied to detect Cryptosporidium species DNA in a total number of 270 fecal samples originating from cattle, sheep and horses in South Africa. DNA was extracted from 0.5 g of fecal material. Results of LAMP detection were compared to those obtained by nested PCR targeting the Cryptosporidium 18 small subunit rRNA (18S) gene. All samples were negative by nested PCR, while up to one-third of samples were positive by LAMP assays. The SAM-1 LAMP assay, shown to detect C. parvum, C. hominis and C. meleagridis, amplified Cryptosporidium DNA in 36 of 107 cattle (33.64%), in 26 of 85 sheep (30.5%) and in 17 of 78 horses (21.79%). The HSP LAMP specific to C. muris and C. andersoni, amplified Cryptosporidium DNA in one cow (0.9%), five sheep (5.8%) and seven horses (8.9%). The gp60 LAMP assay, shown to detect C. parvum produced no amplified Cryptosporidium DNA, likely due to low sample DNA concentrations. The specificity of LAMP assays was confirmed by sequencing of the LAMP products generated in positive samples. Sequence products from the three LAMP assays showed high identity to the target gene sequences confirming the specificity of LAMP. In this study, the LAMP procedure was clearly superior to nested PCR in the detection of Cryptosporidium species DNA. Use of LAMP is proposed as an efficient and effective tool for epidemiologic survey studies including screening of healthy animals in which Cryptosporidium oocyst shedding is characteristically low and likely below the detection limit of PCR in conventional sample concentrates.  相似文献   
40.
施肥对三种切花百合钾素吸收动态的影响   总被引:1,自引:0,他引:1  
通过盆栽土培试验方法,研究了施肥与不施肥(对照)条件下东方百合、麝香百合和亚洲百合3个切花百合品种的钾素吸收规律.结果表明:随着生育期进展,各品种的切花百合地上部各器官含钾量均逐渐降低,地下部器官根和鳞茎则依品种和施肥的不同而表现出差异.鳞茎中的钾素支撑切花百合的前期地上部生长的钾素需求,经历的时间3个品种基本一致,均为47 d.钾素快速吸收期品种之间存在差异,东方百合由花芽分化至切花,历时81 d;麝香百合由花芽分化至切花,历时50 d;由亚洲百合10月6日至切花,历时25 d.施肥均提高了3个品种后期整株的钾积累量,但出现时期因品种而不同,东方百合最早、麝香百合次之、亚洲百合最迟.  相似文献   
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