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961.
A small experiment is described which uses databases of Afro-Caribbeans and Caucasians to establish the quality of information that might be given to an investigator about the ethnic group of the donor of an unknown crime stain. The results show that the technique can provide qualified indications, but categoric conclusions are not, in general, feasible. An appraisal is given of the technique within the operational context.  相似文献   
962.
Lorraine Benson's body was found beaten and strangled at Raynes Park, Surrey, in December 1988. Considering the possibility of linked offences, a murder squad was set up to work alongside a team already investigating a rape series in the Kingston area. A man's handkerchief left at a site a quarter of a mile from the murder scene was found to be stained with blood and saliva matching that of the victim. A DNA profile was obtained from a stain of nasal mucus on this handkerchief and found to match a suspect later arrested for an attempted rape in the same locality. Also of forensic interest were dust marks made by the zips of the victim's and defendant's coats and identification of the rope used for strangulation.  相似文献   
963.
This report describes a collaborative study on typing group-specific component (GC), conducted between the Central Research and Support Establishment and the forensic science laboratories of England, Wales and Northern Ireland. A population study (n=114) was performed. Fifty blood donors were selected to provide a distribution, slightly biased from normal, in favour of the GC 1F-1F and GC 1F-1S phenotypes. A protocol was devised for preparing large bloodstains. The strongest GC bands were obtained from the edge of a stain after the blood had been treated with K+/EDTA. Each laboratory received a representative portion of the large bloodstains for GC typing. Five of the eight laboratories correctly grouped all the bloodstains. No errors directly attitributable to the system were recorded in over 800 tests, indicating that GC in bloodstains can be typed reliably using the combination of isoelectric focusing in ultrathin narrow pH interval gels followed by immunofixation and silver staining.  相似文献   
964.
A simple but rigorous approach is offered for evaluating the evidential value of single locus DNA autoradiographs. This approach does not use a binning technique and it does not treat alleles as discrete variables. Instead, the allele distribution is considered to be continuous. The variation between two comparable bands is assessed using previously determined experimental parameters. The Bayesian treatment leads to an expression of the "quality of a match".  相似文献   
965.
A method for the routine profiling of illicit heroin samples received in casework has been developed which depends on simple and straightforward sample pretreatment, followed by gas chromatography on a capillary column using flame-ionization detection. The factors affecting the choice of each aspect of the procedure are discussed, as are the statistical data for sampling and the chromatography. Components of illicit heroin derived from opium and other adulterants have been identified. The significance of data from samples examined in 1986 is discussed.  相似文献   
966.
The eyes of fourteen fatally abused children and sixteen control cases were examined histopathologically. Ten of the abused children showed intraocular change. The most common ocular changes were subdural hemorrhage of the optic nerve and retinal hemorrhage which involved all the layers of the retina, but most commonly the nerve fiber layer, ganglion cell layer and inner nuclear layer. The presence of blood cavities within the retina partially supported the hypothesis of traumatic retinoschisis. The control cases of non-abused children rarely showed intraocular hemorrhage.  相似文献   
967.
A 54 year-old female expired at her residence. Her husband, a physician, signed a certificate stating that her death was due to cerebrovascular accident (CVA) and released her body to a funeral home, where she was embalmed. Since the deceased had a long history of medical problems and drug abuse, an autopsy was performed and no evidence of CVA was found. Toxicological analyses of body fluids and tissues revealed the presence of ethchlorvynol in high concentration in the bile (112 mg/l). The bloody fluid collected from the heart contained a concentration of ethchlorvynol below the limit for quantitation. Other findings included phenobarbital (32.8 mg/l) in heart bloody fluid and methanol (an ingredient of embalming fluid). The significance of the findings is discussed in relation to embalmment prior to autopsy and toxicological analyses. Ethchlorvynol concentration in the bile is compared to other fatal cases due to ethchlorvynol overdose.  相似文献   
968.
Signs of hypothermia injury were studied in rabbits cooled to a core temperature of 30 degrees C by immersion in ice water and thereafter rewarmed to 35 degrees C. Anaesthetized control rabbits were kept normothermic (37 degrees C) for a corresponding time (4 h). Creatine phosphokinase (CPK) activity increased 24 h after hypothermia to 20-fold in serum. In cerebrospinal fluid the activity was already significantly (5-fold) increased after hypothermia and was still as high at 24 h. Smaller increase was also found in the control normothermic rabbits both in serum (10-fold) and cerebrospinal fluid (2-fold). The values had returned to the initial level after 1 week. Small haemorrhages were observed in the brain at 24 h and slight scarring was seen in the myocardium of some rabbits which had lived 4 weeks following hypothermia. The results indicate that CPK can be a useful marker in the diagnostics of hypothermia death, especially in cerebrospinal fluid, which is less affected than blood by autolysis.  相似文献   
969.
There is broad agreement that neighborhood contexts are important for adolescent development, but there is less consensus about their association with adolescent smoking and alcohol use. Few studies have examined associations between neighborhood socioeconomic contexts and smoking and alcohol use while also accounting for differences in family and peer risk factors for substance use. Data drawn from the Seattle Social Development Project (N?=?808), a gender-balanced (female?=?49%), multiethnic, theory-driven longitudinal study originating in Seattle, WA, were used to estimate trajectories of smoking and alcohol use from 5th to 9th grade. Time-varying measures of neighborhood socioeconomic, family, and peer factors were associated with smoking and alcohol use at each wave after accounting for average growth in smoking and alcohol use over time and demographic differences. Results indicated that living in more socioeconomically disadvantaged neighborhoods, lower family income, lower family general functioning, more permissive family smoking environments, and affiliation with deviant peers were independently associated with increased smoking. Lower family functioning, more permissive family alcohol use environments, and deviant peers were independently associated with increased alcohol use. The effect of neighborhood disadvantage on smoking was mediated by family income and deviant peers while the effect of neighborhood disadvantage on alcohol use was mediated by deviant peers alone. Family functioning and family substance use did not mediate associations between neighborhood disadvantage and smoking or alcohol use. The results highlight the importance of neighborhood, family, and peer factors in early adolescent smoking and alcohol use. Future studies should examine the unique association of neighborhood disadvantage with adolescent smoking net of family socioeconomics, functioning, and substance use, as well as peer affiliations. Better understanding of the role of contextual factors in early adolescent smoking and alcohol use can help bolster efforts to prevent both short and long harms from substance use.  相似文献   
970.
Most previous identity research has focused on relationships between identity synthesis, confusion, and psychosocial problems. However, these studies did not take into account Erikson’s notion of identity consolidation, that is, the dynamic interplay between identity synthesis and confusion. This study aimed to examine longitudinal relationships and the directionality of the effects between identity consolidation and psychosocial problems during adolescence, using two waves of longitudinal data from 793 Japanese adolescents (49.7% girls; ages 13–14 and 16–17 at Time 1). A bi-factor latent change model revealed that levels and changes in identity consolidation were negatively associated with levels and changes in psychosocial problems. Furthermore, a bi-factor cross-lagged effects model provided evidence that identity consolidation negatively predicted psychosocial problems, and vice versa. Our study facilitates a better understanding of the importance of identity consolidation in the relations between identity components and psychosocial problems.  相似文献   
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