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161.
Taphonomic studies regularly employ animal analogues for human decomposition due to ethical restrictions relating to the use of human tissue. However, the validity of using animal analogues in soil decomposition studies is still questioned. This study compared the decomposition of skeletal muscle tissues (SMTs) from human (Homo sapiens), pork (Sus scrofa), beef (Bos taurus), and lamb (Ovis aries) interred in soil microcosms. Fixed interval samples were collected from the SMT for microbial activity and mass tissue loss determination; samples were also taken from the underlying soil for pH, electrical conductivity, and nutrient (potassium, phosphate, ammonium, and nitrate) analysis. The overall patterns of nutrient fluxes and chemical changes in nonhuman SMT and the underlying soil followed that of human SMT. Ovine tissue was the most similar to human tissue in many of the measured parameters. Although no single analogue was a precise predictor of human decomposition in soil, all models offered close approximations in decomposition dynamics.  相似文献   
162.
Abstract:  In response to the unexpected paucity of blood/tissue spatter at the site where a body of an adult woman was dismembered by an electric chainsaw, we dismembered two large pig carcasses with a small electric chainsaw in a controlled environment. These experiments demonstrated first that a large carcass could be easily dismembered by a small electric chainsaw. When the chainsaw bar is held parallel to the ground the majority of the blood and tissue is deposited directly beneath the saw and bar and very little elsewhere. If the discharge chute of the saw however is not oriented directly at the ground, larger amounts of blood and tissue may be sprayed on lateral surfaces or deposited some distance from the chainsaw. The characteristic striations created on the surface of wood as it is cut by a chainsaw can also be found on bony surfaces cut by a chainsaw.  相似文献   
163.
目的 筛选并确证器官组织特异性circRNAs分子标记物,应用于法医器官组织溯源.方法 从TSCD数据库及文献中,筛选出器官组织特异性circRNAs,设计并验证引物.收集心脏、大脑、肝脏、皮肤、骨骼肌、肺脏等人体组织样本,经总RNA提取、RT-qPCR、琼脂糖凝胶电泳等步骤对候选circRNAs进行组织表达水平分析,...  相似文献   
164.
Successful DNA-based identification of mass disaster victims depends on acquiring tissues that are not highly degraded. In this study, multiple protocols for field preservation of tissues for later DNA analysis were tested. Skin and muscle samples were collected from decaying pig carcasses. Tissues were preserved using cold storage, desiccation, or room temperature storage in preservative solutions for up to 6 months. DNA quality was assessed through amplification of successively larger segments of nuclear DNA. Solution-based storage, including a DMSO/NaCl/EDTA mixture, alcohols, and RNAlater preserved DNA of the highest quality, refrigeration was intermediate, and desiccation was least effective. Tissue type and extent of decomposition significantly affected stored DNA quality. Overall, the results indicate that any tissue preservation attempt is far superior to delaying or forgoing preservation efforts, and that simple, inexpensive methods can be highly effective in preserving DNA, thus should be initiated as quickly as possible.  相似文献   
165.
比较了在OP50-NGM、JM109-NGM、OP50-LB、JM109-LB四种不同培养基上秀丽隐杆线虫的生长效果;测定了在三种温度和含不同甘油浓度冻存液中的虫体保存效果。结果显示,秀丽隐杆线虫在OP50-NGM培养基中生长良好,在JM109-LB培养基中生长较差。在-80℃最佳温度条件下,秀丽隐杆线虫在含50mL/L甘油的LB培养基中的存活率达78%;在含50mL/L甘油的PBS中的存活率达52%;而在含100mL/L甘油的水溶液中的存活率仅为8%。用液氮保存,成虫和幼虫均可存活;而在-80℃和-20℃条件下,仅有幼虫存活。结果表明,秀丽隐杆线虫在OP50-NGM培养基中培养发育生长较好;在-80℃条件下,含50mL/L甘油的LB培养基适于保存秀丽隐杆线虫。  相似文献   
166.
介绍了GABA能神经元及其受体的分类,着重阐述了GABA能神经元及其受体在哺乳动物外周组织的分布以及生理效用,为深入了解GABA的活动机制提供了参考,也为GABA功能性商品开发、相关疾病防治及其在动物生产中的应用提供了依据。  相似文献   
167.
Previous studies have examined the effects of heating on teeth; however, none have identified characteristics that allow analysts to differentiate traumatic from heat-induced fractures. This study examined our ability to discern notable differences in preincineration traumatic fractures and heat-induced fractures in postincineration dentition. Twelve anterior dental specimens were subjected to blunt force trauma while a second set were not. All 24 samples were then incinerated in a muffle furnace at a peak temperature (900°C) consistent with house fires. The specimens were subsequently examined with a scanning electron microscope to identify and compare heat-induced and traumatic fractures. The results obtained during examination yielded no differences between the features displayed by specimens that had been inflicted with preincineration trauma and those that did not. Unlike bone, distinguishing features for the differentiation of traumatic and heat-induced fractures could not be compiled.  相似文献   
168.
肌红蛋白降解与人体死亡时间的相关性   总被引:2,自引:1,他引:1  
目的检测人体死亡后骨骼肌中肌红蛋白的降解水平,探讨其与死亡时间的关系。方法分别于人体死后0、4、8、12、24、36、48、60、72h取骨骼肌,置于室温25℃,在不同时间点抽提蛋白质,用Western Blot方法检测肌红蛋白,随后利用生物电泳图像分析软件分析。结果肌红蛋白随死后时间逐步降解。结论肌红蛋白降解的检测可用于推断死亡时间。  相似文献   
169.
何悦  刘云龙 《中国发展》2012,12(2):25-31
电子证据保全公证属于中国公证机构保全证据公证业务范围,具有启动方式被动、无需提供担保、保全措施中立等特点。该文分析了电子证据保全公证在保全对象、申请审查、保全措施、公证书效力等方面与传统证据保全公证的不同,认为需要通过相关立法对其程序规则加以明确。目前中国公证机构仅对电子数据取得行为进行保全公证,随着电子数据鉴定技术的发展,在证据保全公证中引入电子数据原始性公证已不存在技术障碍,为此,该文提出应从法理、效力等层面对电子数据原始性公证展开研究。  相似文献   
170.
This study measured the accuracy of traditional and validated newly proposed methods for globe positioning in lateral view. Eighty lateral head cephalograms of adult subjects from Central Europe were taken, and the actual and predicted dimensions were compared. The anteroposterior eyeball position was estimated as the most accurate method based on the proportion of the orbital height (SEE = 1.9 mm) and was followed by the “tangent to the iris method” showing SEE = 2.4 mm. The traditional “tangent to the cornea method” underestimated the eyeball projection by SEE = 5.8 mm. Concerning the superoinferior eyeball position, the results showed a deviation from a central to a more superior position by 0.3 mm, on average, and the traditional method of central positioning of the globe could not be rejected as inaccurate (SEE = 0.3 mm). Based on regression analyzes or proportionality of the orbital height, the SEE = 2.1 mm.  相似文献   
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