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   3244篇
  免费   1篇
  国内免费   3篇
各国政治   30篇
工人农民   37篇
世界政治   422篇
外交国际关系   143篇
法律   1762篇
中国共产党   241篇
中国政治   162篇
政治理论   343篇
综合类   108篇
  2023年   8篇
  2022年   16篇
  2021年   15篇
  2020年   19篇
  2019年   16篇
  2018年   17篇
  2017年   12篇
  2016年   6篇
  2015年   15篇
  2014年   65篇
  2013年   46篇
  2012年   234篇
  2011年   226篇
  2010年   79篇
  2009年   60篇
  2008年   203篇
  2007年   209篇
  2006年   266篇
  2005年   241篇
  2004年   181篇
  2003年   207篇
  2002年   180篇
  2001年   161篇
  2000年   198篇
  1999年   99篇
  1998年   40篇
  1997年   34篇
  1996年   35篇
  1995年   30篇
  1994年   21篇
  1993年   18篇
  1992年   15篇
  1991年   20篇
  1990年   17篇
  1989年   7篇
  1988年   26篇
  1987年   10篇
  1985年   8篇
  1984年   17篇
  1983年   18篇
  1982年   15篇
  1981年   11篇
  1980年   20篇
  1979年   10篇
  1978年   7篇
  1977年   7篇
  1976年   29篇
  1964年   7篇
  1963年   5篇
  1959年   6篇
排序方式: 共有3248条查询结果,搜索用时 15 毫秒
81.
82.
83.
The level of degradation of DNA as a means for determining the time of death has been proposed as a valid adjunct to the classic thanatochronologic methods. The twofold aim of this work was to determine which organ might reveal both a correlation between the percentage of degradation of the DNA and the time lapse since death, and would be easiest to sample and yield the most reproducible results even in technically unfavorable situations such as on-the-spot investigations at the scene of death. A comparison of the spleen, blood, and liver showed that hepatic tissue best meets these specific needs because it shows a virtually linear correlation between the time elapsed since death and the level of degradation of the DNA, and it can easily be sampled at the scene of death by use of a common biopsy needle.  相似文献   
84.
The compound 1,2-indanedione was recently introduced in our laboratory as an operational reagent for developing latent fingerprints on porous surfaces. As part of the reagent implementation, a study was carried out in order to determine whether either of the two operational 1,2-indanediones formulations interferes with further DNA profiling. Both formulations are based on HFE7100 solvent. One is acidic and the other neutral. In a controlled experiment, known donors attached stamps to envelopes by licking them. The stamped envelopes were initially treated with either one indanedione formulation or the other, and DNA was then extracted for STR typing. No differences were observed between the STR profiles obtained from treated and untreated stamps and envelopes, indicating that 1,2-indanedione does not adversely affect the extraction and subsequent amplification of the STRs examined. However, preliminary results indicate that potential DNA analysis depends on the time interval between the indanedione treatment and DNA extraction as no DNA can be recovered six days following treatment. For this reason, it is strongly recommended to extract DNA from treated items of evidence as soon as possible after indanedione treatment.  相似文献   
85.
Recent studies have shown that the most dimorphic tooth is the mandibular canine. We have carried out a study on a random sample of 146 skeletons dating from the plague outbreak in Marseilles (1722). We studied 1284 maxillary and 1432 mandibular permanent teeth. Sexual dimorphism was tested on 89 individuals. We selected a set of four dental indices and calculated the dimorphism percentage by ratio expression male/female. Dimorphic ranking was made, by allotting the first rank to the tooth presenting the highest dimorphism and the last rank to the one presenting the lowest ratio. Comparisons of means were made on both sexes (sex determined by post-cranial data) through a Student's test (t-test). We noted that lower canines and lateral incisor are the most interesting teeth in the dimorphic dental determination. The lower index presented the highest relative risk with RR = 1.56 [1.04-2.32]. In 58% of the cases, the lower dental index enabled a correct sex determination (determined on the basis of the post-cranial skeleton). These results showed the existence of a relative dental dimorphism (male > female mesiodistal diameters) with humans. In conclusion, this method, using dental measurements, may be used as an additional technique to determine sex on fragmentary adult skeletons, immature material, missing pieces or ambiguities on post-cranial remains.  相似文献   
86.
Glycated hemoglobin (HbA(1c)) has been demonstrated to be a useful marker for long-term glucose control in diabetes. This parameter characterizes each non-enzymatic fixation of glucose on hemoglobin. It is a useful test in addition to periodic glycemia controls since it reflects the mean glycemia of the past 60 days. We studied the conservation of HbA(1c) at 4 degrees C as a function of time with different anti-coagulants and preservatives (3, 6 months, 1 year). A total of 106 tests were performed using the high performance liquid chromatography (HPLC) method dedicated to the semi-automatic analysis of HbA(1c) (Bio-Rad) and we applied the method in forensic cases. Conservation at 4 degrees C was good for as long as 3 months in blood samples collected with fluoride and 6 months in samples collected in a dry or in a heparinized tube. In non-diabetic subjects, HbA(1c) reference values obtained from forensic samples were identical to those of living controls (3.5-6.25% of total hemoglobin). All positive HbA(1c) results were confirmed by a medical evaluation. This method was successfully applied to five forensic cases. In cases of increased acetonemia, acetone or isopropanol are easily measured. However, in some unexplained post-mortem circumstances, increased HbA(1c) permits to differentiate alcoholic or starvation ketoacidosis from the diabetic cases. Glycated hemoglobin should, therefore, be considered the forensic marker of choice in the post-mortem diagnosis of a diabetic disorder and demonstrates its usefulness in post-mortem validation.  相似文献   
87.
This article scrutinises the argument that decreasing hospital autopsy rates are outside the control of medical personnel, based as they are on families' unwillingness to consent to autopsy procedures, and that, as a consequence, the coronial autopsy is the appropriate alternative to the important medical and educational role of the autopsy It makes three points which are well supported by the research. First, that while hospital autopsy rates are decreasing, they have been doing so for more than 60 years, and issues beyond the simple notion of consent, like funding formulae in hospitals, increased technology and fear of litigation by doctors are all playing their part in this decline. Secondly, the issue of consent has as much to do with families not being approached as with families declining to give consent. This is well supported by recent changes in hospital policy and procedures which include senior medical personnel and detailed consent forms, both of which have been linked to rising consent rates in recent years. Finally, the perception that coronial autopsies are beyond familial consent has been challenged recently by legislative changes in both Australia and the United States of America which allow objections based on religion and culture to be heard by coroners. For these reasons, it is argued that medical personnel need to focus on increasing hospital autopsy rates, while also addressing the complex ethical issues associated with conducting medical research within the context of the coronial autopsy.  相似文献   
88.
A simultaneous analytical method for etizolam and its main metabolites (alpha-hydroxyetizolam and 8-hydroxyetizolam) in whole blood was developed using solid-phase extraction, TMS derivatization and ion trap gas chromatography tandem mass spectrometry (GC-MS/MS). Separation of etizolam, TMS derivatives of alpha-hydroxyetizolam and 8-hydroxyetizolam and fludiazepam as internal standard was performed within about 17 min. The inter-day precision evaluated at the concentration of 50 ng/mL etizolam, alpha-hydroxyetizolam and 8-hydroxyetizolam was evaluated 8.6, 6.4 and 8.0% respectively. Linearity occurred over the range in 5-50 ng/mL. This method is satisfactory for clinical and forensic purposes. This method was applied to two unnatural death cases suspected to involve etizolam. Etizolam and its two metabolites were detected in these cases.  相似文献   
89.
90.
There is increasing awareness that domestic violence (DV) and child maltreatment often overlap and that there are significant negative consequences to women and children who are victims in the same families. The present study contains data from a participatory evaluation of a multisite national demonstration project on family violence (the Greenbook Initiative), funded jointly by the U.S. Departments of Health and Human Services and Justice. The goal of this initiative was to increase community capacity to assist dually victimized families. This article focuses on the DV service organizations in the demonstration with regard to collaborations with other agencies and work within the DV system to respond to dually victimized families. Findings suggest that DV agencies participated in leadership roles, cross-system collaborations, and cross-system trainings throughout the initiative. Within-agency practice changes were less apparent. Research and policy implications are discussed.  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