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1.
中国是人口最多的发展中国家,生产生活中产生的有机废弃物数量巨大,堆制有机肥是降低有机废物污染风险的重要方式,而有机肥标准则是防止有机肥成为新的土壤污染源,规范有机肥产业健康发展的重要保障。目前我国有机肥不合格现象时有发生,针对有机堆肥的标准仅有一个8年前的行业标准(NY 525—2012)的现状,本文对比了中国、日本、澳大利亚、欧盟、美国有机肥标准的重要指标,对存在的重金属残留、抗生素污染、病原体污染、营养富集及土壤盐渍化等有机肥质量安全风险问题进行分析,为我国有机肥行业未来绿色、健康、可持续发展提出建议。尽管我国现有有机肥质量标准,在具体指标要求方面优于美国,但和欧盟相比还有差距,比如我国重金属Cu、Zn、Ni限量缺失,对Cd等重金属限值要求不够严格,长期施用会导致土壤重金属含量超过风险筛选值,严重影响农作物安全;同时,由于部分畜禽养殖业不合理使用抗生素,加之有机肥生产企业技术的欠缺,农户施用时缺乏指导,监管部门执法不严等因素,我国有机肥施用过程存在较大风险隐患。因此,进一步完善有机肥标准体系,强化对原料中有毒有害物质的限制,要求选用原料批批检,加大准入和过程的落实力度,才能保障我国有机肥产业有序健康发展。  相似文献   
2.
Canine babesiosis due to Babesia gibsoni (B. gibsoni) displays severe clinical manifestations. Recurrence of babesiosis after anti-babesial treatment is observable in over 10 % of the patients. The present study ascertains the risk factors and cumulative incidence of recurrence of canine babesiosis. For a sample of 145 dogs diagnosed with acute babesiosis, the following parameters were assessed over a period of 16 weeks: haematological parameters, status of anaemia, platelet count, total WBC count, haemoglobin concentration and RBC count, concurrent haemoparasitism, and secondary immune mediated haemolytic anaemia (IMHA). Patient demographics such as age, breed, sex were also recorded. The potential risk factors were statistically evaluated by the cumulative incidence function and the Kaplan-Meier method. The recurrent infections were observed in 11.8 % of the study sample. The following factors were found to associate with increased risk of recurrence: Rottweiler breed (CIR 21.8 % ± 6.9 %; p < 0.05), secondary IMHA (CIR 28.7 % ± 11.3 %; p < 0.05), RBC counts < 2 × 106/μl on the day of diagnosis (CIR 16 % ± 4.6 %; p < 0.05), and persistent anaemia over 20 days post treatment (CIR 29.14 ± 7.9 %; p < 0.001). Dogs with concurrent haemoparasitic infections were predicted to have a fatal outcome in the survival analysis (disease related mortalities 25 % ± 13 %; p < 0.001). According to the findings, veterinarians need to pay attention to Rottweiler breed, dogs with secondary IMHA, concurrent haemoparasitism, low RBC counts on diagnosis and those with persistent anaemia to reduce the risk of relapse.  相似文献   
3.
按照林业有害植物风险分析指标体系,从紫茎泽兰在赫章县的分布状况,传入、定植与扩散的可能性,潜在危害性以及危险性控制的难度等方面入手,对紫茎泽兰传入赫章县的危害性进行了风险分析,并提出了相应的风险管理对策。结果表明,紫茎泽兰传入赫章县后的风险综合评价值(R)为2.45,属于高度危险的风险等级。  相似文献   
4.
基于云计算,结合食品安全检验检测的完备性与最小性原理,将影响食品安全的多维因素降维成平均含量(AVE)、限量标准(STA)、超限率(OUT)、超限程度(OUD)和最大值(MAX)5个因素,并建立食品有毒有害物质检验检测大数据的风险分析算法。利用云计算技术实现对地理上分布广泛、动态、复杂性高的海量数据进行存储,并运用云计算的MapReduce计算框架进行智能的并行数据处理及计算,最后得到风险分析结果。通过对在基于Web端的实验室管理系统采集的1 000 000条检验检测数据结果进行风险分析,得出食品安全指数IFS远小于1,表明消费者人群的食品安全状态良好。  相似文献   
5.
This is the first study to investigate the occurrence, risk factors and hematological findings of hemoplasmas in dogs from Chile. Complete blood count and 16S rRNA conventional PCR for Mycoplasma spp. were performed in 278 blood samples from rural (n = 139) and urban (n = 139) dogs in Valdivia. Real time 16S rRNA PCR (qPCR) allowed species identification. Mycoplasma spp. occurrence was 24.8%. ‘Candidatus M. haematoparvum’ (CMhp) was identified in 12.2% and Mycoplasma haemocanis (Mhc) in 11.9% dogs. It was not possible to identify species in two Mycoplasma spp. samples by qPCR. Sequencing allowed identifying one of them as ‘Candidatus M. turicensis’ (CMt). Frequency in rural localities was higher (41.7%) than in urban (7.9%). Rural locality, maleness and older age were risk factors for hemoplasmosis. Hemoplasma-positive dogs had a higher total protein. This is the first report of Mhc, CMhp and CMt in dogs from Chile, with a high occurrence in rural localities.  相似文献   
6.
7.
The objective of this study was to determine the prevalence of intraoperative electrolyte disturbances and risk factors associated with perianesthetic death in horses undergoing colic surgery. The files of 120 horses meeting the inclusion criteria were reviewed. Data retrieved from the medical records, including demographic data and the occurrence of electrolyte disturbances and other intraoperative complications, were analyzed with a two step-approach by univariate and multivariate logistic regression models. Hypocalcemia was the most represented electrolyte disturbance (52.5%), followed by hypokalemia (30.0%) that was associated with intraoperative administration of salbutamol (P = .045). Perianesthetic death occurred in 46 horses, accounting for an overall mortality rate of 38.3%. Risk factors associated with death were anesthetic duration (P = .001), body weight (P = .020), presence of gastric reflux before anesthesia (P = .021), and intraoperative tachycardia (P = .043) and acidosis (P = .025). The mortality in the study population was comparable to previously reported findings. Based on the study findings, it is advisable to optimize hemodynamics prior to anesthesia, in order to prevent intraoperative tachycardia that is associated with increased risk of death. Heavier horses and those with gastric reflux may have a higher risk of fatalities, and intraoperative salbutamol administration may contribute to hypokalemia.  相似文献   
8.
Decreased iron and zinc bioaccessibility, caused by the anti-nutrient phytic acid, is one of the leading reasons for micronutrient deficiency-related disorders. Biofortification of wheat with phytase gene to enhance iron and zinc bioaccessibility appears to be a fitting solution for this problem, especially in developing countries where most of the population belongs to the lower economic sector. However, societal views on crops, particularly crops that are genetically modified (GM) to express a new trait, needs to be changed. Risk assessment of GM crops can play a crucial role in fostering positive public perception, since it is imperative to ensure safety before allowing human consumption. The present study performed compositional and morphological risk assessment of T3 and T4 generations of phytase transgenic wheat by comparing their biochemical and morphological traits. Transgenic plants were analysed for their carbohydrate, protein, starch and phytic acid content along with iron bioaccessibility, zinc bioaccessibility and phytase enzyme activity. Morphological traits studied included plant height, seed number, seed weight and spike number. No significant differences were observed for carbohydrate, protein, starch content and for morphological traits; however, a significant increase was observed in phytase activity as well as iron and zinc bioaccessibility, which correlated with a significant decrease in phytic acid. These results demonstrate that phytase transgenic wheat is as native as local wheat varieties and can potentially increase iron and zinc bioaccessibility.  相似文献   
9.
从世界分布、主要寄主、经济重要性、传入可能性和风险管理难度5个方面对菜豆细菌性萎蔫病菌传入我国的风险进行评估。结果表明,该病菌是特别危险的有害生物。根据分析结果提出了非疫区输入、输出国应严格检疫、进境口岸加严检查等相应的风险管理措施。  相似文献   
10.
融资租赁具有融资与生产的双重特点,能将资本市场、金融市场与产业市场进行有机融合,实现资金提供方、设备提供方、融资租赁企业和融资需求方等多方共赢。由于涉及多个经营主体,受整个国内外宏观经济影响以及法规和监管的不完善,从而蕴藏了一定的法律风险、市场风险、信用风险和操作风险等。  相似文献   
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