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1.
建立了3,5-二硝基水杨酸分光光度法(DNS分光光度法)测定牛奶中总糖含量的方法,并与国标法(直接滴定法)进行比较.结果显示,DNS分光光度法测定结果的准确度与直接滴定法无明显差异.该法操作简单,试剂消耗体积少,稳定性较高,平均回收率为96%~103%.  相似文献   
2.
Technological advances provide increased ability to transfer human tissues—blood, organs, milk—from one body to another. This article analyzes mechanisms of reality construction in U.S. news to construct shared human breast milk. Articles used typifications and human interest stories to convey participants as victims, lay heroes, and villains. Milk banking was portrayed as institutionally integrated through associations, expert testimonies, and formalized procedures, making banked milk “pure gold.” Peer sharing was portrayed as institutionally opposed through institutional warnings, expert testimonies, informal procedures, and hypothetical atrocities, making peer milk “fool's gold.” Findings suggest that “biovalue” of human milk is interconnected with institutional processing.  相似文献   
3.
Semisoft cheese made from raw sheep's milk is traditionally and economically important in southern Europe. However, raw milk cheese is also a known vehicle of human listeriosis and contamination of sheep cheese with Listeria monocytogenes has been reported. In the present study, we have developed and applied a quantitative risk assessment model, based on available evidence and challenge testing, to estimate risk of invasive listeriosis due to consumption of an artisanal sheep cheese made with raw milk collected from a single flock in central Italy. In the model, contamination of milk may originate from the farm environment or from mastitic animals, with potential growth of the pathogen in bulk milk and during cheese ripening. Based on the 48‐day challenge test of a local semisoft raw sheep's milk cheese we found limited growth only during the initial phase of ripening (24 hours) and no growth or limited decline during the following ripening period. In our simulation, in the baseline scenario, 2.2% of cheese servings are estimated to have at least 1 colony forming unit (CFU) per gram. Of these, 15.1% would be above the current E.U. limit of 100 CFU/g (5.2% would exceed 1,000 CFU/g). Risk of invasive listeriosis per random serving is estimated in the 10?12 range (mean) for healthy adults, and in the 10?10 range (mean) for vulnerable populations. When small flocks (10–36 animals) are combined with the presence of a sheep with undetected subclinical mastitis, risk of listeriosis increases and such flocks may represent a public health risk.  相似文献   
4.
利用1992-2008年河北省、内蒙古自治区、黑龙江省等8个省份面板数据,使用扩展的Nerlovian模型,检验了原料奶供给的反应程度。结果表明:前期产量对原料奶供给的正向作用最大,单产、存栏和WTO规则的影响次之,技术进步的作用较小;饲料价格的反向作用明显,是阻碍产出增长的主要因素;原料奶收购价格缺乏弹性,其短期和长期供给弹性分别为0.109和0.773,均衡状态调整周期约为7.1年。  相似文献   
5.
将初级农产品作为产品责任法中的"产品",其生产者认定为产品责任承担主体,加大对消费者的保护力度,是世界产品责任立法的发展趋势.我国应将生鲜乳等初级农产品纳入产品责任的"产品"范围之内,让缺陷初级农产品生产者对受损害的消费者直接承担产品责任,以有效遏制和防范产品质量安全事件的频发.在 "三鹿奶粉事件"中,缺陷生鲜乳的生产者--收购站应承担产品责任.在产品责任构成要件方面,应该适当降低消费者对因果关系的证明标准.  相似文献   
6.
介绍氢化物发生-原子荧光光谱法测定奶粉中砷含量的不确定度评定方法[1][2]。从测量各步骤评定了不确定度的各项来源[3],对该方法所得分析结果的已识别来源的不确定度影响进行评价。并且可为实验室在该检测过程中进一步提高检测数据的可靠性和一致性作参考。  相似文献   
7.
饮食观念的转变,为奶业大发展提供了广阔的市场空间。特别是美国的饮食文化对促进美国奶业的发展起到了至关重要的作用。通过引导饮食文化的转变,促进中国奶制品的消费,进而找出影响中国奶业发展的又一重要因素,已成为加快我国奶业发展的重要课题。  相似文献   
8.
文章通过对大型钢铁企业的生产流程、采购流程、市场环境、采购策略等内部环境和外部环境调查,分析得出原燃料供应在大型钢铁企业中的地位、作用和特点,并得出相应的供应商管理策略.  相似文献   
9.
社会控制论作为一种法学理论在研究中常常被片面地理解 ,这对于法治和人权的发展都是不利的。为此从分析澄清社会控制的主体、系统构成和维度问题入手 ,进而提出通过法律来设定“人权”作为基本的目标 ,利用指引、支持、规惩、扶持等复合的方式 ,对公权力领域和私权力领域实行两维的社会控制。希望结合我国现行的法律及其制度 ,探讨人权秩序化和走向法治的途径  相似文献   
10.
DDT, DDE, and DDD have been detected at elevated concentrations in sediments and fish of the Yakima River, its tributaries and drainages. An assessment was conducted to evaluate the public health significance of eating fish from the river. This was accomplished by establishing a daily intake level of DDT for the population of greatest concern, and comparing this level to a tolerable daily intake. The most sensitive and highly exposed group was determined to be breastfeeding infants. Infant daily intakes of DDT, based on estimated mother's DDT-breast milk levels, were compared to a recommended tolerable daily intake. Results indicate that mothers who frequently consume Yakima River bottom-feeding fish could have breast milk DDT concentrations sufficiently high to expose their infants to levels above the tolerable daily intake.  相似文献   
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