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991.
Urine is often the sample of choice for drug screening in aviation/general forensic toxicology and in workplace drug testing. In some instances, the origin of the submitted samples may be challenged because of the medicolegal and socioeconomic consequences of a positive drug test. Methods for individualization of biological samples have reached a new boundary with the application of the polymerase chain reaction (PCR) in DNA profiling, but a successful characterization of the urine specimens depends on the quantity and quality of DNA present in the samples. Therefore, the present study investigated the influence of storage conditions, sample volume, concentration modes, extraction procedures, and chemical preservations on the quantity of DNA recovered, as well as the success rate of PCR-based genotyping for DQA1 and PM loci in urine. Urine specimens from male and female volunteers were divided and stored at various temperatures for up to 30 days. The results suggested that sample purification by dialfiltration, using 3000-100,000 molecular weight cut-off filters, did not enhance DNA recovery and typing rate as compared with simple centrifugation procedures. Extraction of urinary DNA by the organic method and by the resin method gave comparable typing results. Larger sample volume yielded a higher amount of DNA, but the typing rates were not affected for sample volumes between 1 and 5 ml. The quantifiable amounts of DNA present were found to be greater in female (14-200 ng/ml) than in male (4-60 ng/ml) samples and decreased with the elapsed time under both room temperature (RT) and frozen storage. Typing of the male samples also demonstrated that RT storage samples produced significantly higher success rates than that of frozen samples, while there was only marginal difference in the DNA typing rates among the conditions tested using female samples. Successful assignment of DQA1 + PM genotype was achieved for all samples of fresh urine, independent of gender, starting sample volume, or concentration method. Preservation by 0.25% sodium azide was acceptable for sample storage at 4 degrees C during a period of 30 days. For longer storage duration, freezing at -70 degrees C may be more appropriate. Thus, the applicability of the DQA1 + PM typing was clearly demonstrated for individualization of urine samples.  相似文献   
992.
Mitochondrial DNA regions HVI and HVII population data.   总被引:2,自引:0,他引:2  
Data from 1393 unrelated individuals have been compiled from eight population groups: African Americans, Africans (Sierra Leone), U.S. Caucasians, Austrians, French, Hispanics, Japanese, and Asian Americans. The majority of the mtDNA sequences were observed only once within each population group (i.e., ranging from a low of 60.3% (35/58) of the Asian American sequences to a high of 85.3% (93/109) of the French sequences). Genetic diversity ranged from 0.990 in the African sample to 0.998 in African Americans. Random match probability ranged from 2.50% in the Asian American sample to 0.52% in U.S. Caucasians. The average number of nucleotide differences between individuals in a database is greatest for the African American and African samples (14.1 and 13.1, respectively), and the least variable are the Caucasians (ranging from 7.2 to 8.4). Substitutions are the predominate polymorphism, and at least 92% of the substitutions are transitions. The most prevalent transversions are As substituted for Cs and Cs substituted for As. For most population groups these transversions occurred predominately in the HVI region; however, the African, African American, and Hispanic samples also demonstrated a large portion of their C to A and A to C transversions in the HVII region (at sites 186 and/or 189). Most insertions occur in the HVII region at sites 309.1 and 315.1, within a stretch of C's. Insertions of an additional C are common in all population groups. The sequence data were converted to SSO mtDNA types and compared with population data on Caucasians, Africans, Asians, Japanese, and Mexicans described by Stoneking et al. [M. Stoneking, D. Hedgecock, R.G. Higuchi, L. Vigilant, H.A. Erlich, Population variation of human mtDNA control region sequences detected by enzymatic amplification and sequence-specific oligonucleotide probes, Am. J. Hum. Genet. 48 (1991) 370-382] using an R x C contingency table test. Differences between major population groups (i.e., between African, Caucasian, and Asian) are quite evident, and similar ethnic population groups carried similar SSO polymorphism frequencies. There were only a few SSO types that showed significant differences between subpopulation groups. The SSO data alone can not be used to describe the population genetics with complete sequence data. However, the results of the SSO comparisons are similar to other analyses, and differences in sequence data in regions HVI and HVII are greater between major population groups than between subgroups.  相似文献   
993.
ABSTRACT

In view of a crisis of liberal universalism peace research must reflect on how it is perceived, how peace is constructed in other places and how it can cope with diversity in ordering and peacebuilding. This Special Issue is an attempt to search starting points for peace research in and with Central Eurasia. The introductory concept clears a path through current research questions, normative problems and barriers of knowledge production. Considering ethnographic methodologies, it starts from the local everyday and takes an interest in how actors and institutions in concrete places and multiple socio-spatial configurations navigate conflict and peace.  相似文献   
994.
ABSTRACT

Studies have shown that long-lived individuals seem to pass their survival advantage on to their offspring. Offspring of long-lived parents had a lifelong survival advantage over individuals without long-lived parents, making them more likely to become long-lived themselves. We test whether the survival advantage enjoyed by offspring of long-lived individuals is explained by environmental factors. 101,577 individuals from 16,905 families in the 1812–1886 Zeeland cohort were followed over time. To prevent that certain families were overrepresented in our data, disjoint family trees were selected. Offspring was included if the age at death of both parents was known. Our analyses show that multiple familial resources are associated with survival within the first 5 years of life, with stronger maternal than paternal effects. However, between ages 5 and 100 both parents contribute equally to offspring’s survival chances. After age 5, offspring of long-lived fathers and long-lived mothers had a 16-19% lower chance of dying at any given point in time than individuals without long-lived parents. This survival advantage is most likely genetic in nature, as it could not be explained by other, tested familial resources and is transmitted equally by fathers and mothers.  相似文献   
995.
ABSTRACT

This article reports the findings of a small-scale qualitative study exploring the experiences of autistic adults who have had experience of the family justice system. While participants related some positive elements to their experiences, in particular with regard to the willingness of professionals to try to learn more about their clients’ needs, the overall picture showed significant concerns. The reports given showed significant misunderstandings about autism, and a system which struggled to make appropriate adjustments which would allow autistic court users to have access to justice on an equivalent basis to non-autistic litigants. This situation stands in contrast to the position regarding other disabilities in the Family Justice System, but also to the relatively greater level of provision for autistic people within the Criminal Justice System. Based on participants’ experiences and existing good practice in other areas, we make recommendations that could be adopted by the Family Court and practitioners.  相似文献   
996.
Abstract

This article reports on timing the adverse effects of black carbon released into the atmosphere from biomass combustion, vehicular emissions and local combustion sources. Black carbon contributes to global warming through its light absorption capacity, has a direct and indirect impact on climate and public health, and will result in ongoing environmental damages and claims. The authors studied measurements of black carbon taken in Delhi, India during 2016 and 2017, and reports on seasonal factors that contribute to higher emissions.  相似文献   
997.
Police witness intelligence stated a murdered adult male “Fred” had been vertically buried in wooded hilly terrain 30 years ago in the Midlands, U.K. Conventional search methods were unsuccessful; therefore, the police requested a geophysical investigation to be undertaken to determine whether “Fred” could be detected. A multiphased geophysical approach was conducted, using bulk ground conductivity and metal detectors, then follow‐up magnetics and ground penetrating radar (GPR) survey profiles on electromagnetic (EM) anomalous areas. A tight grid pattern was used to account for the reduced target size. Relatively high‐resolution EM and GPR techniques were determined optimal for this terrain and sandy soil. Geophysical anomalies were identified and the most promising intrusively investigated, and this was found to be a large boulder and tree roots. Study implications suggest careful multiphase geophysical surveys are best practice and give confidence in cold case searches. This study yielded a no‐body result, effectively saving police time and costs from further investigations.  相似文献   
998.
999.
ABSTRACT

Recently, states have enacted teacher-carry laws. While controversial, little scholarship has tapped public attitudes toward such reforms. Because public opinion shapes policy, the public is an important stakeholder in this debate. Thus, we investigated three questions. First, how supportive is the public of arming teachers? Second, what demographic and social divides exist, if any, for reform approval? Finally, do crime-related perceptions, concerning views about public safety, and criminogenic influences shape policy preferences? We test these questions using a 2018 poll of Virginia residents (N = 521). Overall, approval for teacher-carry is split. Crime-related perceptions mediate some of the initial social and demographic divides in opinion but other correlates, such as parental status, remain salient predictors of views. Implications are discussed.  相似文献   
1000.
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