首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   655篇
  免费   28篇
各国政治   38篇
工人农民   43篇
世界政治   76篇
外交国际关系   30篇
法律   402篇
中国政治   1篇
政治理论   93篇
  2023年   6篇
  2022年   5篇
  2021年   15篇
  2020年   18篇
  2019年   15篇
  2018年   31篇
  2017年   45篇
  2016年   42篇
  2015年   25篇
  2014年   29篇
  2013年   83篇
  2012年   31篇
  2011年   17篇
  2010年   13篇
  2009年   15篇
  2008年   23篇
  2007年   31篇
  2006年   25篇
  2005年   20篇
  2004年   29篇
  2003年   18篇
  2002年   25篇
  2001年   23篇
  2000年   9篇
  1999年   9篇
  1997年   3篇
  1996年   4篇
  1994年   1篇
  1993年   2篇
  1992年   4篇
  1991年   5篇
  1990年   6篇
  1989年   7篇
  1988年   4篇
  1987年   4篇
  1985年   1篇
  1984年   3篇
  1983年   3篇
  1981年   1篇
  1979年   3篇
  1978年   1篇
  1977年   1篇
  1975年   1篇
  1974年   1篇
  1973年   7篇
  1972年   5篇
  1971年   9篇
  1970年   1篇
  1966年   1篇
  1965年   1篇
排序方式: 共有683条查询结果,搜索用时 62 毫秒
641.
642.
643.
A comparison of the Vermont and Maine cases of attempting to control pharmaceutical prices in the year 2000 shows that the Maine legislators were more successful in challenging pharmaceutical industry political power. This comparison shows that challenging the industry was aided by (1) mobilizing public support through grassroots organizations, (2) including independent pharmacists in negotiations over the legislation, and (3) developing state purchasing power leverage.  相似文献   
644.
Male individuals from Maputo (Mozambique) were sampled and 18 Y-STRs were typed: the nine currently used to define the "minimal haplotype" employed in the European, American and Asian "Y-STR Haplotype Reference Databases", as well as the recently described DYS434, DYS437, DYS438, DYS439, DYS460, DYS461, GATA A10, GATA C4 and GATA H4. Allele and haplotype frequencies were estimated in a sample of 112 individuals, where it was possible to define 101 haplotypes, with an observed haplotype diversity (HD) of 0.9973. Allele diversity varied between 0.0179 and 0.9220, DYS385 showing the highest level of polymorphism and DYS392 the lowest. When considering only the most recent Y-STRs, the degree of diversity varied between 0.4011 (DYS438) and 0.6910 (GATA C4), except for DYS434 and DYS437 where a very low diversity was observed (0.0700 and 0.0526, respectively). When analysing the same 112 individuals for the nine Y-STRs included in the minimal haplotype, 78 haplotypes were distinguished with a corresponding observed diversity of 0.9884, a considerably lower value than those for Northern Portugal (n=208; HD: 0.9925) and Macao (n=63; HD: 0.9990). Concerning all 18 Y-STRs studied in this population, the observed diversity demonstrates their usefulness in forensic applications, with the exception of DYS434, DYS437 and DYS392. However, since the informative power of a marker has to be judged in haplotype context, a simple software, allowing the evaluation of the increase of HD through the addition of any combination of new markers to the minimum haplotype was designed. The statistical approach devised, demonstrates that an increment on HD is more rapidly obtained for the Mozambican database when adding GATA A10 or DYS439, DYS460, GATA C4, DYS461 or GATA H4, in this order, to the minimal haplotype. DYS434, DYS437 and DYS438, in conjunction with all the other 15 Y-STRs, do not contribute to an increment on HD. When applying the same approach to an European sample (Northern Portugal), the first three Y-STR choices coincide, but the next order of markers are GATA H4, then DYS437 and finally DYS461. In this sample, DYS434, DYS438 and GATA C4 do not increment HD any further.  相似文献   
645.
The Y-chromosome haplotypes defined by nine STRs (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392 and DYS393) were studied in 207 unrelated individuals from Central Portugal and 63 from Azores Islands. The most common haplotype in Central Portugal was shared by 3.4% of the males, while 160 haplotypes were unique. In Azores Islands the most common haplotype was shared by 6.4% of the males, while 40 haplotypes were unique. The values of haplotype diversity were 0.993 for Central Portugal and 0.976 for Azores Islands.  相似文献   
646.
Y-STR haplotypes are widely studied in Europe and an extensive databasing effort has been conducted (http://www.ystr.org). The distribution of these haplotypes has been considered to present no evidence for substructure at central and southern European level. This picture contrasts with the one that results from Y haplogroups defined by binary markers. This paradox has been solved by admitting that the high STR mutation rate and corresponding recurrence has erased geographic structuration. This explanation prompted us to reanalyse Y-STR haplotypes distribution bearing in mind the commonly admitted model for the generation of diversity in these markers, namely the stepwise mutation model (SMM) and, thus, taking the molecular distance between haplotypes into consideration. Accordingly, we have studied the European distribution of the two most frequent haplotypes in the Iberian Peninsula and their one step neighbours using the European samples deposited in the Y STR database (http://www.ystr.org). For the first group we found a clear-cut decreasing W-E gradient, while for the second the highest frequencies were found in the Iberian Peninsula (3.98% in Portugal and 3.85% in Spain), dropping to 2.88% in France and showing a less well defined SW-NW gradient. Furthermore, we have tested the agreement between haplotype groups and binary markers haplogroups in a random sample of 292 individuals from Northern Portugal. Our results demonstrate that (a) Y-STR haplotype data can be used for wide-scale anthropological approaches disclosing information that has been considered only available through binary markers and (b) forensic use of continental databases needs careful refinement, due to the macro-geographic pattern now evidenced.  相似文献   
647.
This study introduces a Portuguese-language version of psychopathy checklist-revised (PCL-R) [Harv. Mental Health Lett. 12 (1995) 4] in the Brazilian penitentiary system. Hare's scale is used extensively in many other countries. In a forensic population sample of 56 male subjects classified as psychopaths and non-psychopaths [Manual for the Hare Psychopathy Checklist-Revised, Multi-Health System, Toronto, 1991], 33 correlated to global personality disorder (GPD) and 23 to partial personality disorder (PPD), respectively, subtypes of antisocial personality disorder [Manual for the Hare Psychopathy Checklist-Revised, Multi-Health System, Toronto, 1991]. Subjects were evaluated through psychiatric and neurological examinations, review of judicial records, Rorschach and PCL-R. A control group of 30 subjects without criminological or psychiatric history was also evaluated with the same instruments. PCL-R validation and identification of cutoff score for Psychopathy (GPD group) was assessed through the concurrent use of the Rorschach. PCL-R cutoff score for the Brazilian population was set at 23. Sensitivity was determined at 84.8%, and reliability was high (Kappa index = 0.87). GPD individuals were characterized as clearly psychopathic according to PCL-R criteria while PPD individuals can only be considered mildly psychopathic, with better chance of rehabilitation.  相似文献   
648.
The objective of this study was to investigate characteristic injuries of pedestrians and bicyclists (unprotected) compared to motor vehicle occupants' (protected) in fatal traffic accidents. Cases of 664 fatal traffic accidents (371 pedestrians, 45 bicyclists, and 248 motor vehicle occupants) were collected from 1999 to 2001 using the database of the Forensic Institute in Budapest. Autopsy reports were analyzed. Location of injuries, blood alcohol levels, seasonal distribution and natural diseases influencing accident outcome were evaluated. For statistical analysis, odds ratio (OR) with 95% confidence interval (CI) was used by a conditional logistic regression. There were substantial differences in distribution of injuries suffered by pedestrians, bicyclists and motor vehicle occupants. Among pedestrians and bicyclists there was a higher rate of head injuries, such as skull fractures, epidural haemorrhage, subdural haemorrhage, brain contusion, and injuries of the lower extremities. Thoracic damages, such as traumatic aortic rupture, hemothorax, and abdominal damages, like liver rupture were dominant in motor vehicle occupants. Considering existing natural diseases, coronary artery disease was the only one with higher occurrence among motor vehicle occupants 24 (9.7%) compared with pedestrians and bicyclist 36 (8.6%). These results underline the importance of preventive strategies in transportation, pointing out that different methods are necessary to reduce fatal injuries of various traffic participants.  相似文献   
649.
SNPs in forensic genetics: a review on SNP typing methodologies   总被引:17,自引:0,他引:17  
There is an increasing interest in single nucleotide polymorphism (SNP) typing in the forensic field, not only for the usefulness of SNPs for defining Y chromosome or mtDNA haplogroups or for analyzing the geographical origin of samples, but also for the potential applications of autosomal SNPs. The interest of forensic researchers in autosomal SNPs has been attracted due to the potential advantages in paternity testing because of the low mutation rates and specially in the analysis of degraded samples by use of short amplicons. New SNP genotyping methods, chemistries and platforms are continuously being developed and it is often difficult to be keeping up to date and to decide on the best technology options available. This review offers to the reader a state of the art of SNP genotyping technologies with the advantages and disadvantages of the different chemistries and platforms for different forensic requirements.  相似文献   
650.
The atlas and axis ossification centers of 106 human fetal and neonate skeletons were measured. The skeletons belong to the collection in the Department of Forensic Medicine of the Albert Szent-Gy?rgyi Medical University, Szeged, Hungary. The age of the skeletons ranged from 4 to 10 lunar months. Nine linear measurements on the atlas, seven on the axis neural arches ossification centers and three on each one of the axis centra ossification centers were taken. We did simple and multiple linear regression analysis to estimate the age of fetuses. The results show that it is possible to use regression equations to estimate the fetal body length and age from atlas and axis ossification centers measurements during the whole period of development studied. The study of size and shape of the ossification centers using factorial analysis (principal component analysis) shows that the shape of the dens of the axis might be useful to estimate fetal viability.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号