全文获取类型
收费全文 | 703篇 |
免费 | 65篇 |
专业分类
各国政治 | 9篇 |
工人农民 | 15篇 |
世界政治 | 7篇 |
外交国际关系 | 4篇 |
法律 | 560篇 |
中国共产党 | 10篇 |
中国政治 | 49篇 |
政治理论 | 22篇 |
综合类 | 92篇 |
出版年
2024年 | 2篇 |
2023年 | 8篇 |
2022年 | 9篇 |
2021年 | 8篇 |
2020年 | 29篇 |
2019年 | 25篇 |
2018年 | 10篇 |
2017年 | 38篇 |
2016年 | 32篇 |
2015年 | 17篇 |
2014年 | 31篇 |
2013年 | 68篇 |
2012年 | 38篇 |
2011年 | 59篇 |
2010年 | 45篇 |
2009年 | 42篇 |
2008年 | 49篇 |
2007年 | 57篇 |
2006年 | 31篇 |
2005年 | 21篇 |
2004年 | 30篇 |
2003年 | 27篇 |
2002年 | 14篇 |
2001年 | 20篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 5篇 |
1995年 | 3篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有768条查询结果,搜索用时 15 毫秒
531.
Assessment of changes in the spongy bone structure of the upper end of the humerus is one of the common methods of age estimation. This method was devised many years ago (1894) and has never been verified in an objective numerical testing. We projected an objective morphometric method assessment of the upper end of the humerus. The study was carried out on humeri from cadavers of 88 men and 84 women. The surface area of atrophy of the spongy structure (medullary cavity) was calculated on the longitudinal section of the humerus. A new morphometric method was applied, which allowed numerical presentation of results. The results of the study show a lack of statistical correlation between atrophy of the spongy structure within the upper end of the humerus and the chronological age. Therefore, it can be concluded that the assessment of humerus structure should be omitted in the forensic medical age estimation. 相似文献
532.
Fernandes MM Tinoco RL de Braganca DP de Lima SH Francesquini Junior L Daruge Junior E 《Journal of forensic sciences》2011,56(6):1616-1619
Developing teeth are commonly the criteria used for age estimation in children and young adults. The method developed by Cameriere et al. (Int J Legal Med 2006;120:49-52) is based on measures of teeth with open apex, and application of a formula, to estimate chronological age of children. The present study evaluated a sample of panoramic radiographs from Brazilian children from 5 to 15 years of age, to evaluate the accuracy of the method proposed by Cameriere et al. The results has proven the system reliable for age estimation, with a median residual error of -0.014 years between chronological and estimated ages (p = 0.603). There was a slight tendency to overestimate the ages of 5-10 years and underestimate the ages of 11-15 years. 相似文献
533.
Textile fibres were transferred to a pig skin carcass and their persistence determined at daily intervals for up to a 12 day period during which time the carcass was left outdoors exposed to the prevailing weather conditions and animal activity. In the absence of strong winds and precipitation, the loss of fibres was found to be exponential. Stronger winds and heavier precipitation caused an increase in the rate of loss of fibres. The results of this study showed that the majority of fibres transferred to a body deposited outdoors, can be expected to be lost after the first 2 days, however, none of the experiments performed resulted in a complete loss of fibres, even after 12 days exposure. These persistence characteristics differed from those observed in a similar study using small sections of skin, rather than carcasses.The implications of the results of the present study in relation to the examination of fibre evidence in cases of homicide are discussed. 相似文献
534.
目的观察橡胶弹射人口的形态特征,并探讨其法医学意义。方法使用9mm警用转轮手枪发射橡胶弹,在实验动物胸腹部侧面垂直射击,射击距离分别为紧密接触射击(0cm),相对接触射击(1~6cm),近距离射击(6-60cm)和远距离射击(60cm~有效射程25m)。92式手枪采取相同方式射击实验动物作为对照。观察射入口的形态特征,制作组织病理学切片,HE染色显微镜下观察。结果橡胶弹接触射击和近距离射击,射入口边缘整齐,有明显的擦拭轮、挫伤轮和火药斑纹;远距离射击,可见射人口边缘撕裂,挫伤轮明显增宽,皮下出血显著;与手枪弹射入口形态特征明显不同。结论9mm警用转轮手枪橡胶弹射入口典型的形态特征,可作为此类损伤的诊断指标。 相似文献
535.
Byard RW 《Journal of forensic sciences》2011,56(Z1):S252-S254
Death from incised wounds of major vessels may occur during illegal entry of premises. Wounds are often relatively unimpressive having been caused by thin shards of glass. Alcohol and/or drugs have often been taken that have impaired coordination and contributed to a failure to take appropriate action. A 37-year-old man slipped and fell while attempting to enter a house through a window that he had just broken. He was found dead surrounded by a large amount of blood. At autopsy, a single horizontal, deeply incised wound of the anterior neck was present with transection of the internal jugular veins bilaterally and the right common carotid artery. Toxicological studies were negative for alcohol and common drugs. Death was due to exsanguination and air embolism. This case demonstrates that the injuries sustained during such activities may be quite extensive and involve major neck vessels. Alcohol and drug intoxication are not necessarily involved. 相似文献
536.
Azrak B Victor A Willershausen B Pistorius A Hörr C Gleissner C 《Journal of forensic sciences》2007,52(1):146-150
The aim of this study was to establish correlations of clinical and radiological dental findings, alone or in combination, with chronological age in adults. Dental findings and orthopantomograms of 984 patients (aged 20-60 years; 524 females/460 males) were analyzed. DMF-T index and distance (alveolar bone level, ABL) between cemento-enamel junction and alveolar bone margin were recorded. Additionally, clinical and radiological findings at each tooth crown and root were collected according to the actual status of destruction and restoration, and a total score for each dentition (TSD) was calculated. After univariate correlation analysis, correlation coefficients for ABL and TSD were improved by using square root (sqrt). However, the determination accuracy was still not satisfactory; 90% of the residuals were in the range of about +/-10. The present study showed that clinical and radiological dental findings could not be used, not even in combination, for accurate age estimation as a single method, but that they could support other methods. 相似文献
537.
The literature provides linear regression formulas for dental age estimation that is based on radiological two-dimensional measurements of the pulp size. The aim of the present study was to explore whether the previously presented regression formulas could lead to statistically sound results and to appropriate repeatability when applied to young individuals. Orthopantomograms (OPGs) of 44 Austrian individuals, aged between 13 and 24 years, were selected at random. In accordance with the reported method, six teeth on each OPG were chosen to carry out the measurements. Statistical analysis was performed in order to assess the difference between the estimated and the true chronological age. The regression formulas reported by Kvaal et al. (1995) led to a consistent underestimation; the regression formulas reported by Paewinsky et al. (2005) resulted in a constant overestimation of age. The statistical analysis of intraobserver and interobserver variation revealed a variation width below 2%, respectively. 相似文献
538.
目的探讨皮肤挫伤修复过程中,caspase-6在挫伤区及挫伤周边区不同时间表达的变化规律。方法应用免疫组化染色、Westernblot技术显示caspase-6在皮肤挫伤区及挫伤周边区炎性细胞中的阳性表达和激活情况。结果伤后3h,挫伤区内浸润的少量多核粒细胞的胞质中caspase-6呈弱阳性表达,阳性率为(25.78±1.38)%;伤后12h,阳性表达增强明显,阳性率为(47.70±5.14)%;伤后3d,几乎所有多核粒细胞、单核细胞和成纤维细胞中caspase-6呈强阳性表达,阳性率为(54.58±5.64)%,表达达高峰,以后逐渐下降。Westernblot实验证明,caspase-6酶原表达呈现时间规律性变化。结论大鼠皮肤挫伤修复过程中,caspase-6在挫伤后的炎症反应中发挥重要作用;同时,caspase-6在挫伤区内多核粒细胞、单核细胞及成纤维细胞中的表达呈规律性变化,可对挫伤时间的推断提供参考。 相似文献
539.
Critics of giving citizens under 18 the right to vote argue that such teenagers lack the ability and motivation to participate effectively in elections. If this argument is true, lowering the voting age would have negative consequences for the quality of democracy. We test the argument using survey data from Austria, the only European country with a voting age of 16 in nation-wide elections. While the turnout levels of young people under 18 are relatively low, their failure to vote cannot be explained by a lower ability or motivation to participate. In addition, the quality of these citizens' choices is similar to that of older voters, so they do cast votes in ways that enable their interests to be represented equally well. These results are encouraging for supporters of a lower voting age. 相似文献
540.
To date, there has been no chronological age estimation according to third-molar mineralization in eastern Turkish children and adolescents. The aim of this study was to analyze the development of the mandibular third molar and its relationship to chronological age in subjects aged 7-22 years according to Demirjian's stages. The final sample consisted of 1348 [622 males (mean age, 12.72 ± 3.14) and 726 females (mean age, 12.92 ± 2.89)] conventional orthopantomograms from eastern Turkish youths. An independent t-test was performed to evaluate the difference between sexes. Regression analysis was performed to obtain regression formulae for dental age calculation with chronological age. In males, there was a difference between males and females only at stage C (p = 0.03); females were advanced 0.37 years compared with males at the stage C. Third-molar development among eastern Turkish children and youths occurs at a more advanced age than other populations for almost all stages. 相似文献