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   5601篇
  免费   228篇
各国政治   291篇
工人农民   235篇
世界政治   450篇
外交国际关系   256篇
法律   3611篇
中国政治   40篇
政治理论   919篇
综合类   27篇
  2023年   43篇
  2022年   34篇
  2021年   60篇
  2020年   109篇
  2019年   135篇
  2018年   185篇
  2017年   218篇
  2016年   200篇
  2015年   147篇
  2014年   189篇
  2013年   603篇
  2012年   185篇
  2011年   188篇
  2010年   128篇
  2009年   123篇
  2008年   175篇
  2007年   165篇
  2006年   161篇
  2005年   128篇
  2004年   153篇
  2003年   135篇
  2002年   120篇
  2001年   214篇
  2000年   163篇
  1999年   121篇
  1998年   55篇
  1997年   55篇
  1996年   41篇
  1995年   62篇
  1994年   51篇
  1993年   64篇
  1992年   87篇
  1991年   92篇
  1990年   82篇
  1989年   66篇
  1988年   86篇
  1987年   86篇
  1986年   100篇
  1985年   112篇
  1984年   92篇
  1983年   81篇
  1982年   41篇
  1981年   36篇
  1979年   35篇
  1978年   32篇
  1975年   33篇
  1974年   49篇
  1971年   33篇
  1970年   31篇
  1968年   32篇
排序方式: 共有5829条查询结果,搜索用时 15 毫秒
231.
This paper reviews the evolution of programme and performance budgeting (PPB) in Malaysia from its beginning in 1969, through the in-depth implementation phase which began in 1972, to the present day. It outlines the system in the Ministry of Health, where PPB has been extensively developed and comments on the systems established in other in-depth ministries, in several of which little appears to have been achieved. In 1981 all other agencies were asked to adopt PPB in their budget submissions. Compliance has been superficial. The paper explores the constraints to the further development of PPB. These range from difficulties of securing appropriate staff, lack of top-level commitment and information problems, to the inherent difficulties of programming and performance measurement. In seeking to evaluate the success of PPB the paper adopts two approaches. The first, involving a small questionnaire survey amongst those involved in PPB, reveals rather guarded opinions concerning its usefulness and progress. The second, which explores the use made of PPB, reveals little use by legislators, budget officers or line managers, and no link between PPB and the planning process. However the audit department expresses considerable interest in relation to performance auditing. In summary the achievements of PPB have been modest.  相似文献   
232.
233.
Since the concept of "brain death" was introduced in medical terminology, enough evidence has come to light to show that the concept is based on an unclear and incoherent theory. The "brain death" concept suffers by internal inconsistencies in both the tests-criterion and the criterion-definition relationships. It is also evident that there are residual vegetative functions in "brain dead" patients. Since the content of consciousness is inaccessible in these patients who are in a profound coma, the diagnosis of "brain death" is based on an unproved hypothesis. A critical evaluation of the role and the limitations of the confirmatory tests in the diagnosis of "brain death" is attempted. Finally it is pointed out that a holistic approach to the problem of "brain death" in humans should necessarily include the inspection of the content of consciousness.  相似文献   
234.
With increasing frequency, relatively small, fragmentary evidence thought to be osseous or dental tissue of human origin is submitted to the forensic laboratory for DNA analysis with the request for positive identification. Prior to performing DNA analysis, however, it is prudent to first perform a presumptive test or "screen" to determine whether the questioned material may be eliminated from further consideration. When material is shown not to be consistent with bone/teeth, DNA testing is not performed. When such determinations cannot be made from gross morphological features, elemental analysis can be indicative. This presumptive test is made possible by applying scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) in conjunction with an X-ray spectral database recently developed by the FBI laboratory. This database includes spectra for many different materials including known examples of bone and tooth from many different contexts and representing the full range of taphonomic conditions. Results of SEM/EDS analysis of evidence can be compared to these standards to determine if they are consistent with bone and/or tooth and, if not, then what the material might represent. Analysis suggests that although the proportions and amounts of calcium and phosphorus are particularly important in differentiating bone and tooth from other materials, other minor differences in spectral profile can also provide significant discrimination. Analysis enables bone and tooth to be successfully distinguished from other materials in most cases. Exceptions appear to be ivory, mineral apatite, and perhaps some types of corals.  相似文献   
235.
The projection of the cornea from the bony orbit has been determined, in facial approximation, by centrally locating the eyeball in the orbit and positioning the cornea so that its most anterior point falls in line with a tangent dropped from the mid-superior to the mid-inferior orbital rim. However, there appears to be no scientific evidence to justify this guideline; yet, there have been numerous studies that measure globe projection in living subjects, from the lateral orbit using an exophthalmometer. The aim of this study was to determine if the traditional facial approximation guideline is consistent with the exophthalmometry literature. MRI research shows that corneal projection is underestimated using the traditional facial approximation guideline. An underestimation is also strongly supported by statistical comparisons of globe projection measures taken using more traditional instruments (e.g., Hertel's exophthalmometer) to skull morphology (p < 0.006). It is suggested that the traditional facial approximation guideline not be used in future facial approximations since it appears to under-predict anterior globe projection by 4 mm on average. It is also suggested that average exophthalmometer values be used until more accurate and precise ways of determining globe projection have been determined.  相似文献   
236.
237.
The authors evaluated the usefulness of the postmortem biochemical analysis of ionic ratios in different parts of the heart and their relation to cardiac damage caused by chest trauma, as observed by anatomopathologic study. Fifty-nine 59 cases were studied, selected from routine necropsies, and samples were taken from different sites of cardiac tissue. The cause of death was trauma in 40 cases and nontraumatic causes in 19 cases. The object of this study was to analyze the levels of Na+, K+, Ca+2, Mg+2, and Zn+2 in different zones of the heart, and the relationship between intracellular and extracellular ion ratios and the different causes of death and any anatomopathologic alterations observed. The biochemical tests revealed a possible relation between the ionic values and cause of death. Alterations in cell membrane permeability and corresponding modification of the ionic ratios were produced earlier than histologic alterations, which need longer to establish themselves whether or not they follow a traumatic process.  相似文献   
238.
To investigate socioemotional influences on children's eyewitness accuracy, we examined children's reports for activities they were motivated to conceal. Forty-eight 3–6-year-old children participated in a standardized play session with their mothers. Half of the children were told by an experimenter not to play with certain toys, but did so at the urging of their mothers, who told their children to keep the play activities secret. The remaining children were not restricted from playing with the toys, nor told by their mothers to keep the play activities secret. Later, all children were interviewed about the activities with free narrative and detailed questions. Half were given an interview that consisted of highly suggestive questions; half were given an interview consisting of specific, less suggestive questions. Results indicated that older children who were instructed to keep events secret withheld more information than did older children not told to keep events secret. Younger children's reports were not significantly affected by the secret manipulation. There were no significant effects associated with interview type. We discuss implications for understanding the development of children's knowledge and use of secrecy, and applications of the research to issues that arise when child witnesses give reports in legal contexts.  相似文献   
239.
Since forensic facial approximations are used to promote recognition of a deceased person, an accurate forensic facial approximation (FFA) should be easily recognized as the person to whom the skull belonged (target individual). However, the accuracy of FFAs has been previously assessed by the direct comparison of an FFA to the corresponding target individual for similarity (i.e., a resemblance rating). Resemblance ratings may not indicate a facial approximation's accuracy since the resemblance of non-target individuals is not accounted for. This experiment tests the validity of using resemblance ratings to assess the accuracy of FFAs. The study indicates that there is no statistically significant difference between: (a) resemblance ratings of FFAs to target individuals and (b) resemblance ratings of FFAs to individuals incorrectly identified as the target individual. It is concluded that it is not possible from resemblance ratings to determine the accuracy and/or quality of a facial approximation since a non-target individual may receive a resemblance rating equal to, or higher than, the target individual.  相似文献   
240.
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