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881.
882.
Quality assurance samples submitted from the NCSBI as part of a contract with TBTG to outsource DNA Database samples showed unexpected discrepancies for the locus D16S539 when all other loci yielded identical results. Discrepancies observed included allele drop out and an imbalance in sister alleles with samples returned from TBTG. This led to a comprehensive review of the technical procedures used between the two laboratories to determine the cause of the discrepancies noted for the locus D16S539, since both laboratories were using the PowerPlex 1.1 typing kit from the Promega Corporation. The NCSBI and the TBTG utilize different extraction methods (organic extraction vs. FTA) and amplification conditions (AmpliTaq vs AmpliTaq Gold), respectively, so the exact cause of discrepancy observed was not immediately apparent. Experiments at the NCSBI associated the observed allele drop out and the imbalance of the sister alleles with the use of AmpliTaq Gold and a hot start procedure. Sequencing data revealed that a point mutation resides on the D16S539 primer-binding site that reaches polymorphic levels in African-American populations. This led to the development of a degenerate primer by the Promega Corporation to detect "missing" alleles when AmpliTaq Gold is used. The degenerate primer was then thoroughly tested to show its efficacy in detecting the "true" D16S539 profile when used.  相似文献   
883.
Forensic comparison of soils by bacterial community DNA profiling   总被引:5,自引:0,他引:5  
This preliminary investigation has shown that a soil microbial community DNA profile can be obtained from the small sample of soil recovered from the sole of a shoe, and from soil stains on clothing. We have also shown that these profiles are representative of the site of collection and therefore could potentially be used as associative evidence to prove a link between suspects and crime scenes. Soil community profiles were obtained using the T-RFLP fingerprinting method that uses fluorescent primer technology and semi-automated analysis techniques similar to those used in human DNA profiling in forensic laboratories.  相似文献   
884.
We reviewed all 50 body packer deaths in New York City from 1990 to 2001. The majority (37/50) of deaths were caused by acute intoxications due to open or leaking drug packets in the gastrointestinal tract. The number of packets recovered ranged from 1 to 111 (average 46). The weight of the combined packets ranged from 9.4 to 1,200 g (average of 377). The age ranged from 19 to 57 years (mean 37.1). The decedents were: 82% male, 66% Hispanic, 24% Black, and 10% White. The manners of death were 47 accidents, 1 homicide, 1 natural, and 1 undetermined. The causes of death included 42 acute intoxications, 5 intestinal obstructions/bowel perforations, 1 gunshot wound, 1 intracerebral hemorrhage due to hypertensive disease, and 1 undetermined. Of the 50 decedents, 42 were transporting opiates, 4 cocaine, and 4 both opiates and cocaine. There were 9 deaths from 1990-1995 and 41 from 1996-2001. Of the 41 deaths between 1996 and 2001, only 6 involved cocaine. In New York City there has been an increase in body packer deaths from the early 1990s to the late 1990s. Along with this increase is a marked predominance of opiate body packer deaths with few cocaine deaths.  相似文献   
885.
This study extends the literature on policy feedback and explores the extent to which public attitudes reflect learning from past government initiatives. We analyze the ways in which feedback mechanisms affecting public attitudes may differ from those earlier identified in the literature. We apply this general analytic framework to help explain variation in public attitudes toward private employer involvement in health care, explore possible causal pathways, and offer some preliminary empirical tests of these hypotheses. There are different levels of public support for the notion of employer obligation involving medical care, long-term care, and the treatment of substance abuse. Our evidence suggests that lessons about the performance of institutions in each of these policy domains represent the most important effect of existing policy on public attitudes. Furthermore, these differences correspond to what one would expect based on our model of policy feedback and cannot be explained by other plausible sources of policy legitimacy.  相似文献   
886.
Kneed to know     
Starr M 《Newsweek》2002,140(24):88, 90
  相似文献   
887.
Chronic factitious disorder with physical symptoms, or Munchausen syndrome, is a well-recognized but uncommonly diagnosed psychiatric condition characterized by the deliberate production of signs and symptoms of disease in order to receive medical attention. Clinical suspicion of this disease is rarely confirmed by autopsy, as the patients usually do not die as a consequence of feigning illness. Here we report the autopsy confirmation of a case of a suspected Munchausen syndrome patient who presented with a history of cystic fibrosis. Examination of the lungs demonstrated extensive severe interstitial fibrosis, and polariscopic examination revealed a large quantity of crystalline material throughout the tissue; X-ray diffraction identified the material as talc. Synopses of published cases of Munchausen syndrome presenting as cystic fibrosis, and cases of Munchausen syndrome with pulmonary talcosis are presented as part of the discussion.  相似文献   
888.
The current study investigated whether the presence of school-based mental health clinicians in an urban school district was associated with reduced out-of-school suspension rates. Forty one elementary schools with expanded school mental health (ESMH) programs were compared to 41 schools without ESMH programs. Correlational analyses revealed associations between suspension outcomes and several school-level demographic variables including school attendance rate, percent of students in poverty, and percent of nonwhite students in the school. After controlling for these variables, however, results of stepwise linear regressions demonstrated no significant differences between ESMH and non-ESMH schools on suspension outcomes. Results of the current study suggest that the presence of ESMH clinicians will not necessarily impact suspension rates in an elementary school. Targeted and well-implemented approaches to address behaviors that lead to suspension, or school- and system-level policies to provide alternatives to suspensions, will likely be a better route to achieving this outcome.  相似文献   
889.
890.
This article represents the work of the National Association of Medical Examiners Ad Hoc Committee on shaken baby syndrome. Abusive head injuries include injuries caused by shaking as well as impact to the head, either by directly striking the head or by causing the head to strike another object or surface. Because of anatomic and developmental differences in the brain and skull of the young child, the mechanisms and types of injuries that affect the head differ from those that affect the older child or adult. The mechanism of injury produced by inflicted head injuries in these children is most often rotational movement of the brain within the cranial cavity. Rotational movement of the brain damages the nervous system by creating shearing forces, which cause diffuse axonal injury with disruption of axons and tearing of bridging veins, which causes subdural and subarachnoid hemorrhages, and is very commonly associated with retinal schisis and hemorrhages. Recognition of this mechanism of injury may be helpful in severe acute rotational brain injuries because it facilitates understanding of such clinical features as the decrease in the level of consciousness and respiratory distress seen in these injured children. The pathologic findings of subdural hemorrhage, subarachnoid hemorrhage, and retinal hemorrhages are offered as "markers" to assist in the recognition of the presence of shearing brain injury in young children.  相似文献   
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