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991.
Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry have been used to examine evidence in a sexual assault investigation. Because condoms are being used increasingly by sexual assailants and some condom brands include the spermicide nonoxynol-9 (nonylphenoxy polyethoxyethanol) in the lubricant formulation, the recovery, and identification of nonoxynol-9 from evidence items may assist in proving corpus delicti. A method was developed for the recovery of nonoxynol-9 from internal vaginal swabs and for its identification by reverse phase liquid chromatography/electrospray ionization mass spectrometry (LC ESI-MS), nanoelectrospray ionization (nanoESI) mass spectrometry, and high resolution MALDI Fourier transform mass spectrometry (MALDI-FTMS). The method was tested on extracts from precoitus, immediate postcoitus, and four-hours postcoitus vaginal swabs provided by a volunteer whose partner does not normally use condoms, but for this trial used a condom having a water-soluble gel-type lubricant that includes 5% nonoxynol-9 in its formulation. Subsequently, LC ESI-MS was used to identify traces of nonoxynol-9 from the internal vaginal swab of a victim of a sexual assault.  相似文献   
992.
In order to establish an animal model for entomotoxicological studies, the kinetics of morphine elimination from blood after a single intravenous injection of morphine and the concentration of morphine in tissues following a continuous perfusion were studied. The aim of these experiments was to obtain controlled morphine tissue concentrations similar to those encountered in fatal human heroin overdoses. These tissues can be used as a food source for developing fly larvae in entomotoxicological studies. In the single injection experiment, seven rabbits were administered 1 or 2 mg/kg body weight of morphine chlorhydrate via the main ear artery. Blood samples of 200 microL were removed regularly via a catheter. Morphine concentration was determined using RIA techniques. Morphine was found to be first rapidly distributed and then slowly eliminated, following a two-exponential equation. Elimination of morphine from blood can be described as a two-compartment model. Constants of the equation were determined using the Kaleidagraph program. Using those constants, the main pharmacokinetics parameters were calculated. Results of these parameters showed the following: clearance from 13.3 to 16.2 L.h.1, half-life of the distribution phase from 0.6 to 0.9 min, and half-life of the elimination phase from 21 to 26 min. These results were used to calculate the rate of perfusion of morphine for rabbits to obtain desired, controlled, and constant concentrations of morphine in tissues. In the second experiment, three rabbits received a perfusion of morphine intravascularly at a rate of 2 mg/kg/h for a period of 3 h. These rabbits were sacrificed and analyses performed on several abdominal and thoracic organs. Results showed that the concentrations of morphine differed according to the organ analyzed, but were reproducible for organs between animals. These concentrations were similar to those normally encountered in cases of human death due to heroin overdoses.  相似文献   
993.
In order to use genetic loci in forensic identity testing, some population data are needed. This paper presents a report of allele frequency data for the loci HUMTH01, HUMTPOX and HUMVWA in a population sample from Northern Spain. No deviation from the Hardy-Weinberg equilibrium was detected in any of the three markers investigated and there was no evidence of association between the alleles of these loci. Statistical analysis was also carried out to obtain some parameters of medicolegal interest and comparative studies were carried out with other populations studied to date for these five loci. The Asturian sample does not differ substantially from other Caucasian and Spanish populations.  相似文献   
994.
Deaths attributed to ingestion of Nicotiana glauca are extremely rare. We report here a case where a 43-year-old man was found dead after apparently drinking a water extract of Nicotiana glauca. The primary alkaloid in the plant is anabasine. Toxicological analysis by capillary gas chromatography showed the deceased had a blood anabasine concentration of 2.2 mg/L. Clinically, the features of poisoning are nicotine-like and if death occurs it results from respiratory paralysis. The case further supports the view that, in the human, anabasine is considerably more toxic than nicotine.  相似文献   
995.
DISTANCE DECAY REEXAMINED   总被引:2,自引:0,他引:2  
The "journey to crime," or the study of the distance between an offender's residence and offense site, has been a subject of study within criminology for many years. Implications arising from such research touches the majority of criminological theories. An overriding conclusion from this line of research is that most crimes occur in relatively close proximity to the home of the offender. Termed the distance-decay function, a plot of the number of crimes that an offender commits decreases with increasing distance from the offender's residence. In a recent paper, Van Koppen and De Keijser raise the concern that inferring individual distance decay from aggregate-level data may be inappropriate. They assert that previous research reporting aggregated distance-decay functions conceals individual variations in the ranges of operation, which leads them to conclude that the distance-decay function is an artifact. We do not question the claim that researchers should not make inferences about individual behavior with data collected at the aggregate level. However, Van Koppen and De Keijser's analysis raises four important issues concerning (1) the interpretation of the ecological fallacy, (2) the assumption of linearity in offender movements, (3) the interpretation of geographic work on profiling, and (4) the assumption of random target selection within a delimited range of operation. Using both simulated and nonsimulated data, we present evidence that reaches vastly different conclusions from those reached by Van Koppen and De Keijser. The theoretical implications of our analyses and possibilities for future research are addressed.  相似文献   
996.
Do minorities live in higher crime neighborhoods because they lack the class resources to live in better areas, or do racial differences in exposure to crime persist even for blacks and whites of comparable backgrounds? Does living in the suburbs reduce exposure to crime equally for whites and blacks? This study analyzes the determinants of living in local areas with higher or lower crime rates in the Cleveland metropolitan region in 1990. Multivariate models are estimated for whites and blacks, with separate models for city and suburban residents and for violent crime and property crime. Within the city, exposure to both types of crime is strongly related to socioeconomic status for both races, but there are also strong independent effects of race on exposure to violent crime. In the suburbs, whites are concentrated in communities with low crime rates regardless of their social class. There are substantial class differences among suburban nonwhites, but even afluent blacks live in places with a higher violent crime rate than do poor whites.  相似文献   
997.
No reliable data are available on cases of lethal child abuse (by active force) in the area of the former German Democratic Republic. In a multicenter study we therefore examined the police and court records for such cases occurring in the period 1 January 1985 to 2 October 1990 in the entire area of the former German Democratic Republic. RESULTS: The study center received information on 39 cases of lethal child abuse which correspond to approximately 7 cases per year. However, a low percentage of undetected crimes which cannot be determined more precisely has to be taken into consideration. Almost 40% of the victims were younger than 1 year, 73% of the victims showed indications of repeated ill-treatment. The effects caused by using direct blunt forces, against the head in particular, were by far the most frequent causes of death. The male contact person (the victim's father, brother or stepfather as well as the life companion of the child's mother in particular) killed the child in most of the cases. As far as it is known, 37% of the male/female offenders suffered from chronic alcoholism; 32% of the male/female offenders were under the influence of alcohol when the crime happened. 83% of the male/female offenders who were found guilty made a confession shortly after the crime had happened or during the interrogations. Almost all the male/female offenders were sentenced to prison (the duration of the imprisonment varied between one year and for life). Due to the considerably lower section rate compared to the one in the German Democratic Republic, it is to fear that each second fatal child abuse is not detected in the new federal states.  相似文献   
998.
The life cycle of a fly illustrates that the late immature stages of necrophagous insects frequently leave the body, and are therefore not found on the corpse itself. Taking into account these stages (i.e. pupae) while investigating a death scene is very important. Two case histories demonstrate the effects of not taking that fact into consideration when determining the post-mortem interval. Since there is no standardized method in Germany for collecting insects at a death scene, an entomological collection kit with a short instruction is introduced.  相似文献   
999.
No reliable data are available on cases of lethal child abuse (by active force) in the area of Federal Republic of Germany prior to reunification (the former West Germany). In a multicenter study we therefore examined the police and court records for such cases occurring in the period 1 January 1985 to 2 October 1990 in nearly the entire area of Federal Republic of Germany. RESULTS: The study center received information on 58 cases of lethal child abuse. Extrapolated to all institutes of legal medicine, this corresponds to 62 cases in all of West Germany in the period studied. An approximately equal number of unreported cases should be added to this figure. Including unreported cases, at least 20 cases of lethal child abuse occurred per year; thus only one in every two cases ever came to light. Almost two thirds of the victims were younger than one year old. At autopsy 59% exhibited signs of repeated abuse at autopsy. By far the most common cause of death was direct impact from a blunt object, usually to the head. Mostly, the male person to whom the victim relates most closely (father, stepfather, partner of the mother) has killed the child. Twenty-one of the 74 persons charged saw the charges against them dropped or were acquitted due to lack of evidence; 51 received sentences ranging from one year probation to life. In the remaining two cases the outcome of the trial was unknown. Signs of abuse were readily apparent at autopsy in almost all cases. The high number of unreported cases underscores the need to educate medical students and practicing physicians to be on the look-out for signs of abuse and argues for an increase in the rate of autopsy.  相似文献   
1000.
Many theories of crime have linked low levels of socioeconomic status (SES) to high levels of delinquency. However, empirical studies have consistently found weak or nonexistent correlations between individuals' SES and their self-reported delinquent behavior. Drawing upon recent theoretical innovations (Hagan et al., 1985; Jensen, 1993; Tittle, 1995), we propose that this apparent contradiction between theory and data may be reconciled by recognizing that SES has both a negative and a positive indirect effect upon delinquency that, in tandem, results in little overall correlation between the two. We tested this proposal with longitudinal data from the Dunedin Multidisciplinary Health and Development Study. We used measures of parental SES recorded at study members' birth through age 15, social-psychological characteristics at age 18, and self-reported delinquency at ages 18 and 21. We found that low SES promoted delinquency by increasing individuals' alienation, financial strain, and aggression and by decreasing educational and occupational aspirations, whereas high SES promoted individuals' delinquency by increasing risk taking and social power and by decreasing conventional values. These findings suggest a reconciliation between theory and data, and they underscore the conceptual importance of elucidating the full range of causal linkages between SES and delinquency.  相似文献   
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