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891.
In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition.  相似文献   
892.
The aim of the present investigation was to reconstruct the chronological age based on the dental developmental stages of third molars evaluated on orthopantomograms. A total of 1175 orthopantomograms were assembled from patients of Caucasian origin between 16 and 22 years of age. Each third molar present was scored by two observers according to a 10-stage developmental scale. The kappa statistics measured the intra- and inter-observer reliability. The general statistical analysis was based on multiple regression analysis in order to obtain multiple regression formulas for dental age estimation based on the number of third molars present on the evaluated orthopantomogram. No regression models were statistically significant when there was only one-third molar present because of the relatively small number of orthopantomograms that fitted this criterion. A strong agreement was found between the intra- and inter-observer measurements. The statistical analysis revealed both for males and females high Pearson correlation coefficients between contralateral third molars and smaller coefficients between antimeres. The obtained multiple regression formulas are only applicable in certain specified conditions, for instance when four third molars are present the following formulas should be used in a Caucasian male "age=10.2000+0.5122UL+0.5273LL" (developmental stage of upper and lower left third molars) or in case of a female "age=13.6206+0.1933UR+0.5080LR" (developmental stage of upper and lower right third molars). This investigation revealed that the chronological age of a Caucasian individual may be estimated based on regression formulas with a S.D. of 1.52 or 1.56 years for males and females, respectively, when all four third molars are present.  相似文献   
893.
Prehistoric Polynesian skeletal remains are frequently being recovered in New Zealand due to the increasing pace of urbanisation. Since such material must often be reinterred quickly, it is important that the sex of individuals be determined from the remains in a relatively short time. For this purpose, discriminant function analysis was utilised for sex determination of prehistoric adult New Zealand Polynesian tali (24 males and 27 females). Five measurements were taken and subjected to Statistical Package for the Social Sciences (SPSS) discriminant function analysis. For the discriminant functions derived, accuracy of sex determination ranged from 85.1 to 93.3%. Reduction in error over random assignment by sex ranged from 70 to 87%.  相似文献   
894.
Allele frequencies for the three STR loci included in the GenePrint CTT multiplex system (HUMTH01, HUMTPOX, HUMCSF1PO) have been determined for the four major sub-populations of New Zealand.  相似文献   
895.
Child death due to repeated episodes of physical assault or neglect has been termed the child abuse-maltreatment syndrome (CAMS). We characterized the injuries in a series of fatally abused or maltreated child to delineate objective diagnostic criteria for the CAMS for use by clinicians and pathologists. All deaths (age <17 years) investigated by the Office of the Chief Coroner for Ontario, Canada during the time period 1990-1995 were reviewed. Cases of CAMS were defined as death due to lethal recent injury or malnutrition in the presence of significant old (healing or healed) injuries indicative of repeated episode of inflicted trauma. The nature and frequency of the various injuries was determined. The frequency of the shaken baby syndrome, and the types and frequency of ano-genital injuries were also studied. Twenty-one cases of fatal CAMS were found in the study period. Most cases had significant recent head injury with intra-cranial hemorrhage (71%). Other significant recent injuries commonly observed included blunt injuries of the skin and soft tissues (67%), blunt abdominal trauma with visceral injuries (14%), and fractures (18%). Eight cases (38%) fulfilled accepted criteria for the shaken baby syndrome. Many children with fatal head injuries had evidence of older head trauma (38% of all cases). A significant minority of cases had evidence of malnutrition due to neglect (10%) or ongoing ano-genital injuries (10%). Most cases of child homicides due to repeated episodes of abuse or maltreatment involve head trauma including shaken baby syndrome. Fractures of long bone and ribs, the classical markers of child abuse, were relatively infrequent compared with head injury. A proportion of cases had ano-genital injuries due to repeated sexual abuse or punitive maltreatment. All clinicians and pathologists must recognize the wide spectrum of injuries in child abuse to ultimate protect the victim or other children in an at-risk situation.  相似文献   
896.
897.
The percentage of skeletal remains that can be sexed depends on the degree of completeness of the skeleton, the parameters that are used and the type of statistical analysis that is done. The objective of the present study was to assess the accuracy of the demarking point in sexing the femur of South African whites and blacks. One hundred pairs of femurs were randomly selected from the bone collections of each of the two racial groups. The bones were sexed by measuring the head diameters and comparing them with the corresponding demarking point values that had been previously determined. The sex that was so allocated to each bone was compared with its documented sex in the database in order to assess the accuracy of the method. The overall success rate of sex identification was 32% for both white and black populations, but the accuracy of sexing was 100%.  相似文献   
898.
Prior research has indicated that pubertal development and peer associations are important determinants of adolescent smoking behavior. However, more remains to be learned about why these variables matter or how they may be related to one another in ways that lead to the initiation of smoking. Using contractual data from the National Longitudinal Study of Adolescent Health, we consider the relationship between early pubertal development and associations with close friends who smoke, and smoking initiation among male youths. The results of the study reveal a link between advanced pubertal development and the initiation of smoking among boys, but we discover that the effect is indirect, mediated by a greater propensity of sexually mature males to forge friendships with peers who smoke. We also find that this propensity is greatest among the youngest adolescents in the sample, suggesting that the age of the respondent conditions the effects of pubertal development on the formation of friendships with peers who smoke.(Ph.D., The University of Texas at Austin), is an Assistant Professor at Washington State University at Vancouver. Her areas of interest include juvenile delinquency and substance abuse.(Ph.D., Rutgers: The State University of New Jersey) is an Assistant Professor at Westfield State College. Her area of interest is adolescent identity development.(Ph.D., The University of Texas at Austin) is an Associate Professor at the University of Portland. His areas of interest include biosocial models of adolescent problem behavior.  相似文献   
899.
The purpose of this study was to examine age and gender differences in peer conflict, particularly in regards to conflict issues and resolution strategies reported by children and adolescents. Students from grades 4 and 8 (60 boys, 60 girls) were asked interview questions and given 3 hypothetical scenarios to respond to. Teacher and self-reports were also gathered for each student to assess their level of adaptive ability. The results showed that adolescents tended to report higher rates of conflict and endorsed more cooperative strategies than 4th graders, who endorsed more aggressive tactics. Female students reported having more relational issues and used more conflict-mitigating strategies, while boys reported having more conflicts related to status/dominance. Finally, links were also found between effective resolution strategies and social ability. The implications and limitations of this study are discussed.M. A. Noakes received her Master's degree from the Department of Educational Psychology at the University of Alberta, Canada. Her current research interests include assessment of at-risk youth, relapse prevention programs for young offenders, and social emotional functioning of children and adolescents.C. M. Rinaldi her doctorate from the Department of Educational and Counselling Psychology at McGill University, Canada. Her current research interests include applied developmental psychology, social emotional functioning of children and adolescents, and parent-child relations.  相似文献   
900.
This investigation addressed the question of how two forms of social cognitive reasoning – epistemic reasoning and adolescent egocentrism – interface with externalizing and internalizing forms of psychopathology during adolescence. Adolescents’ epistemic reasoning (i.e., types of belief entitlement, or degree of doubt, held by an individual when confronted with contradictory sides of an issue), and imaginary audience and personal fable ideation, were assessed in a sample of 29 adolescent boys with behavioral problems and 30 of their peers without behavioral problems. To assess internalizing and externalizing symptomatology, teachers completed the Child Behavior Checklist (CBCL-TRF). Results revealed that, compared to those without behavior problems, boys with behavioral problems were lower in epistemic reasoning. Further analyses revealed consistent relations between dimensions of social cognitive reasoning to specific forms of psychopathology. These findings suggest that social cognitive reasoning, particularly epistemic doubt, is important in understanding problem behaviors among typical and atypical adolescents.
Kathleen M. BeaudoinEmail:
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