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41.
The estimation of bloodstain volume using fractal analysis of digital images of passive blood stains is presented. Binary digital photos of bloodstains of known volumes (ranging from 1 to 7 mL), dispersed in a defined area, were subjected to image analysis using FracLac V. 2.0 for ImageJ. The box-counting method was used to generate a fractal dimension for each trial. A positive correlation between the generated fractal number and the volume of blood was found (R(2) = 0.99). Regression equations were produced to estimate the volume of blood in blind trials. An error rate ranging from 78% for 1 mL to 7% for 6 mL demonstrated that as the volume increases so does the accuracy of the volume estimation. This method used in the preliminary study proved that bloodstain patterns may be deconstructed into mathematical parameters, thus removing the subjective element inherent in other methods of volume estimation. 相似文献
42.
从“血荒”现象看《献血法》在实施中的问题与完善 总被引:2,自引:0,他引:2
我国《献血法》在实施中存在一些问题:“血荒”现象在很多地方存在;目前的还血政策不能很好地激励公民献血的积极性;法律对医疗机构紧急用血规定不完善,“见死不救”,“救人违法”的矛盾在现实中还存在;部分临床用血的血液来源存在安全隐患。应当教育、动员、招募一支固定无偿献血者队伍,适当放宽献血的条件。提高血站的管理水平和服务质量、加强无偿献血及免费用血系统的网络化建设、适当扩大医疗机构在紧急用血时的权限。 相似文献
43.
目的建立血液中硫化氢的气相色谱质谱联用分析方法。方法取心血3mL-5mL,置于20mL顶空瓶中,加入1g氯化钠,加3mL-5mL蒸馏水,加入2mol/L盐酸1mL,加盖密封,混匀后于80℃水浴中加热20min。取液上气体0.5mL进样分析。结果在中毒死亡者的心血中检出硫化氢,保留时间参考值为3.6min。结论该方法可用于刑事案件中硫化氢的快速分析。 相似文献
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为克服土地资源的不足,三岩峡谷历史地形成了农业与牧业两种生产方式并存的经济结构。农牧并举的二元经济结构也在很大程度上影响了三岩峡谷内部的社会及文化。与土地相关的一系列技术与文化成为当地的文化核心,而其他的文化要素都根源于三岩人使用土地的技术。由此导致三岩的二元结构并没有与社会的阶序化相结合,也没有形成人群之外的二元划分,而是始终依附于特定生态与自然环境以及与此相适应的血缘群体。 相似文献
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目的比较7种一氧化碳中毒血样分光光度含量测定方法的特点及适用性。方法用空白血添加一氧化碳配制不同浓度的样品,采用双波长法、还原法(3种)、切线法和导数光谱法(2种)进行检测,对各种方法线性范围、重现性和操作中注意事项等内容进行考察,并用实际案件检材验证和比较。结果还原法一在30%~70%、还原法三在20%~100%,其他方法在20%~70%范围内,线性关系良好;样本浓度超过或低于50%,采用切线法有一定误差;导数法及还原法三因需要制备CO饱和样本,操作略微繁琐,但导数光谱法计算结果准确性好。结论几种方法均可用于一氧化碳中毒血的检测,实验结果可为方法的实际应用提供借鉴和帮助。 相似文献
48.
An HPLC‐DAD method was developed to detect and quantify a neonicotinoid insecticide acetamiprid (ATP) and its metabolite IM‐1‐2 in autopsy samples of a fatal intoxication case. The postmortem blood and tissue distribution of ATP and IM‐1‐2 was determined for the first time. The method showed acceptable precisions and recoveries with relative standard deviations of <10% for ATP level and 1.38 % for IM‐1‐2. The detection and quantification limits for ATP were 0.015 μg/mL and 0.030 μg/mL for blood and were 0.035 μg/g and 0.050 μg/g for liver samples, respectively. The mean contents of ATP were 0.79 μg/g in the liver, 47.35 μg/g in the stomach contents and 2.7 μg/mL in the blood. IM‐1‐2 content was 17.0 μg/g in the stomach contents. ATP and IM‐1‐2 were not detected in the urine. The presence of ATP and IM‐1‐2 in the samples was confirmed by GC‐MS. The method can be exploited in future forensic casework. 相似文献
49.
目的:建立生物检材血液中农药的快速溶剂萃取(accelerated solvent extraction,ASE)法。方法通过优化ASE萃取条件,考察萃取温度、时间和萃取剂对回收率的影响,提取血液中的农药进行气相色谱-质谱联用(GC/MS)法定性定量分析。结果血液中8种农药的平均回收率在70.6%~92.4%,变异系数小于5.0%,8种农药在0.5~5.0μg/mL的浓度范围内线性良好。结论该方法具有操作简便快捷、回收率高、重现性好等特点,可用于农药的提取检验。 相似文献
50.
Curt E. Harper PhD Dani C. Mata MS Dayong Lee PhD 《Journal of forensic sciences》2023,68(5):1686-1697
Fentanyl has emerged as the most prolific drug in the ongoing opioid epidemic and has greatly impacted traffic safety in recent years. This study aimed to evaluate fentanyl prevalence and concentrations in blood and oral fluid in driving under the influence of drugs (DUID) cases in three different regions (i.e., Alabama, Orange County, CA, and Houston, TX) from 2017 to 2022. Furthermore, traffic fatalities were evaluated for Alabama and Orange County, CA. Fentanyl positivity in DUID and traffic fatalities increased for most years in this study. In Alabama, the prevalence of fentanyl DUID cases increased 4-fold in 2022 compared to 2017. Orange County's increase from 2017 to 2022 was 14-fold. In Houston, the increase was approximately 2-fold from 2019 to 2022. The greatest increase for all laboratories coincided with the start of the COVID-19 pandemic. In 2022, the median fentanyl DUID blood concentrations were 4.7, 11, and 4.7 ng/mL in Alabama, Orange County, and Houston, respectively. Most fentanyl cases were polydrug cases (≥90%). Methamphetamine, THC, and alprazolam were the most frequently detected drugs in combination with fentanyl. Alabama has collected oral fluid and blood in DUID cases since 2018. The detection of fentanyl in oral fluid was comparable to blood. However, 59% and 8.7% of fentanyl-positive cases had concentrations of >20 ng/mL in oral fluid and blood, respectively. Therefore, oral fluid as an alternative or supplemental specimen to blood is an attractive approach for fentanyl in DUID cases. This study contributes to understanding recent fentanyl trends and their impact on traffic safety. 相似文献