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111.
Abstract: This study introduces a method to classify individuals according to an age threshold, given sex and third molars’ dental maturity measured on the Demirjian scale by expressing uncertainty on dental evidence (soft evidence). We introduced a procedure to learn the parameters of the Naïve Bayes model, and we discussed two classification rules. The model was estimated and tested on 559 Italians aged 16–22. Two experts provided the dental evaluations, and the model was estimated for each of them. We evaluated the coherence of the evidence provided by the experts. Some indexes have been proposed to evaluate the effectiveness of the models, emphasizing how the experts’ ability and the technology affect the results. We introduced two benchmarks, one based on the sample distribution per sex and age: in this case, probability of correct classification increases 22% and the proportion of false adults impressively decreases 80.2%; the other benchmark, obtained by simulating hard evidence, shows how the use of soft evidence increases the proportion of correct classification 3.1% and decreases the crucial proportion of false adults about 20%. Similarly, the proportion of false minors decreases about 5.3%.  相似文献   
112.
This study examines the reliability of age estimation utilizing the Greulich and Pyle atlas in relation to a modern Scottish population. A total of 406 left‐hand/wrist radiographs (157 females and 249 males) were age‐assessed using the Greulich and Pyle atlas. Analysis showed that there was a strong correlation between chronological age and estimated age (females R2 = 0.939, males R2 = 0.940). When age groups were broken down into year cohorts, the atlas over‐aged females from birth until 13 years of age. The pattern for males showed that the atlas under‐estimated age until 13 years of age after which point it consistently over‐aged boys between 13 and 17 years of age. This study showed that the Greulich and Pyle atlas can be applied to a modern population but would recommend that any analysis takes into account the potential for over‐ and under‐aging shown in this study.  相似文献   
113.
The study evaluated secular trends in dental development during a period of 30 years, correlation between dental and chronological age in Istria and the littoral region of Croatia. The sample consisted of 1000 panoramic radiographs of children, aged 6–16 years (mean 10.0 ± 1.8), taken in the period 1977–1979 (N = 500; 243 females) and 2007–2009 (N = 500; 299 females). Dental age was assessed according to Demirjian's method. Correlation between chronological and dental age was linear, positive, high, and statistically significant in both periods and genders, ranging from 0.73 to 0.86. Dental age was underestimated when compared to chronological age by 1 year on average, more 30 years ago (?1.35 ± 1.17) than today (?0.63 ± 1.09), less for girls (?0.80 ± 1.22) than boys (?1.21 ± 1.10). A statistically significant positive secular trend in acceleration of dental development was present of 0.72 years during the 30‐year period and was more significant in girls than boys (0.83‐ and 0.51‐year acceleration).  相似文献   
114.
Studies of public support for capital punishment have consistently observed a strong and enduring gender gap in the level of death penalty support, with males consistently more inclined than females to support capital punishment. This unexplained relationship has endured over time and space as well as across a myriad of research designs. The present study uses attribution theory in a factorial survey design to account for this relationship. Analyses of data obtained from jurors provide mixed support for attribution theory yet fails to bridge the gender gap in death penalty support. The implications of these findings as they relate to gender, socialization, and attributions are discussed.  相似文献   
115.
Because arrest rates are especially high for teenagers and young adults, criminologists have long contended that age structure changes affect crime trends. In recent years, however, this belief has been drawn into question because crime has not declined even though high-crime age groups have shrunk. We argue that the age/crime relationship is probably exaggerated because the high arrest rates for younger persons are due partly to their lesser ability to escape arrest, younger persons commit more group crime, and the age structure of victims should be taken into account. We then review 90 studies that regress crime rates on age structure; only a small minority consistently finds significant relationships. Because of methodological problems in this research, one cannot conclude that the age/crime relationship does not exist, but the weight of evidence shows that forecasts based on demographic trends are not likely to be helpful.  相似文献   
116.
We examined the utility of CT scans in the evaluation of degree of ectocranial suture closure. Five cranial points (left and right midcoronal positions, left and right midlambdoidal positions, and the lambda) were evaluated in 231 CT scans using a three‐point scoring system (open, partial closed, and closed). The slice increment and thickness varied between three groups of the scans. The results showed a good correlation between degree of suture closure and increasing age in each group. Young individuals (<40 years) and old individuals (>60 years) could be clearly distinguished from the middle‐aged individuals. ANOVA test revealed no difference between two groups of scans and between left and right sides (> 0.05). Interobserver agreement was good, especially considering the score by sides. The results of this study create the base for developing a robust and simple method to estimate the age at death using CT scans.  相似文献   
117.
Abstract:  This study evaluates a new method of fetal age estimation based on orbital measurement and including the potential trisomy 21 of the fetus. Six orbital and one facial CT-scan measurements were taken on 71 fetuses ranging from 14 to 41 weeks of gestational age. Forty-eight fetuses were "normal" and 23 fetuses presented the Down syndrome (trisomy 21). The anatomy/imagery correspondence was evaluated comparing our results to those obtained by direct bone measurements on the same fetuses and revealed no significant differences between the two kinds of measurements. Moreover, a multiple linear stepwise regression was realized to estimate fetal age and showed that the "trisomy 21 parameter" is not conserved in the final determination model. Therefore, we conclude that the good radio-anatomical correspondence offers an interesting alternative to direct bone measurement (necessitating dissections) and allows a reliable fetal age determination, whatever is the trisomy 21 condition of the fetus.  相似文献   
118.
目的观察大潮气量机械通气致兔急性肺损伤(acutelung injury,ALI)后,肺组织中血管内皮生长因子(VEGF)的动态变化,探讨其在损伤时间推断中应用的价值。方法57只雄性新西兰大白兔随机分为正常组(3只)、对照组(27只)和实验组(27只)。机械通气(V_T 60mL/kg)致AL后于0,1,3,6,12,18,24,36,48h各处死动物3只。取肺组织,测量右上肺组织湿干重比(W/D),肺组织进行HE及免疫组织化学染色并进行图像定量分析,观察VEGF变化规律。结果正常组VEGF有低水平表达;大潮气量机械通气1min后至肺损伤后12h,实验组VEGF表达水平与正常组无明显差异(P>0.05);12~48h随损伤时间的延长VEGF表达水平持续上升,48h仍处于较高水平,其间各时间点VEGF表达水平与正常组比较均有显著性差异(P<0.05)。结论大潮气量机械通气致兔ALI 2d内,VEGF在肺组织炎症发生、发展和愈合修复过程中存在时间相关性,对法医病理推断呼吸机所致的ALI时间具有参考价值。  相似文献   
119.
RUS-CHN图谱骨龄评价法用于推侧青少年年龄   总被引:3,自引:1,他引:2  
目的探讨RUS-CHN(RC)图谱评价法用于13~18岁青少年年龄推侧的应用价值。方法4 424名(男2 272,女2 152)13~18岁正常城市汉族青少年,以简化RUS-CHN法建立手腕骨发育等级图谱。另以1 048名(男530,女518)13~18岁青少年为检验样本,比较不同方法骨龄与生活年龄的差异。结果RUS-CHN图谱法可仅评价桡骨、尺骨远端和第III指的4块掌指骨骺。检验样本中男14~17岁、女13~16岁年龄组,RC图谱法骨龄与生活年龄之间的差异均无统计学显著性(W ilcoxon符号秩和检验,P>0.05),对男18岁、女17岁组出现显著性差异的可能原因进行了讨论。结论RUS-CHN图谱法骨龄适用于男13~18岁、女13~17岁青少年的年龄推测。  相似文献   
120.
Caspase3和iNOS在人挫伤脑组织中的时序性表达   总被引:1,自引:0,他引:1  
目的研究人脑挫伤后不同时间半胱氨酸天冬氨酸蛋白酶3(caspase3)和诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)表达的变化,为法医实践中脑损伤时间的推断提供依据。方法选择30例因颅脑损伤死亡案例为损伤组,5例非颅脑损伤急死的案例为对照组,应用免疫组织化学和图像分析技术,分别于死亡后2h、4~8h、10~14h、1~2d、3~5d及8~11d检测脑组织标本中caspase3和iNOS的变化规律。结果经统计学分析:(1)caspase3阳性细胞表达在伤后2h以内组开始升高,与对照组相比差异有统计学意义(P〈0.05),1~2d组表达强度增高,3~5d组仍见高表达(P〈0.05),以后逐渐下降。(2)iNOS阳性细胞表达在2h以内组与对照组比较差异无统计学意义(P〉0.05),伤后4~8h开始升高(P〈0.05),1~2d组表达强度最高,以后逐渐下降,伤后8~11d仍有弱表达(P〈0.05)。结论caspase3和iNOS的表达可能成为实际检案中脑损伤时间推断的有效依据。  相似文献   
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