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991.
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.  相似文献   
992.
The medicolegal and subsequent criminologic interpretation of forensic and pathological findings in cases of homicide makes up an important tool of case profiling. In a retrospective study of 26 cases of "multiple homicides" involving 31 perpetrators (30 males, 1 female, mean age 33.5 years) and 73 victims (33 males, 40 females, mean age 36 years, 68 fatalities, 5 survivors), autopsy reports and prosecution authorities' files were investigated with regard to individual characteristics of victims and offenders, circumstances as well as mode of commitment. The major aim of this study was to comprehensively elucidate and characterise relevant forensic and criminologic features, which may gain importance for forensic case profiling. Forty-six victims were found in the close social environment of the perpetrator and 45 homicides were committed either in the victim's, the perpetrator's or the shared domicile. The main motives included concealment of a crime (n=13), personal conflicts/domestic arguments (n=7) and greed (n=12). The relevant injuries with regard to the cause of death were attributable to sharp force (n=13), blunt force (n=7), gunshot wounds (n=24), ligature strangulation (n=3), smothering (n=5), fire/carbon monoxide (n=4) and combined impacts (n=11). In 15 cases, so called defence injuries were found. In 5 victims a post-mortem blood alcohol concentration >1.5 g/l was determined. In six perpetrators, a severe psychiatric impairment of juridical responsibility was ascertained (Section 20 German criminal code, n=2, psychosis; Section 21 German criminal code, n=4, acute alcohol intoxication). As far as conviction data were available, 27 crimes were juridically assessed as murder, 12 as manslaughter and one as bodily harm with fatal consequences.  相似文献   
993.
Spontaneous pneumomediastinum commonly occurs in healthy young men or parturient women in whom an increased intra-alveolar pressure (Valsalva maneuver, asthma, cough, emesis) leads to the rupture of the marginal pulmonary alveoli. The air ascends along the bronchi to the mediastinum and the subcutaneous space of the neck, causing cervico-fascial subcutaneous emphysema in 70-90% of cases. Ninety-five forensic cases, including five cases of hanging, were examined using postmortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy until December 2003. This paper describes the findings of pneumomediastinum and cervical emphysema in three of five cases of hanging. The mechanism of its formation is discussed based on these results and a review of the literature. In conclusion, when putrefaction gas can be excluded the findings of pneumomediastinum and cervical soft tissue emphysema serve as evidence of vitality of a hanged person. Postmortem cross-sectional imaging is considered a useful visualization tool for emphysema, with a great potential for examination and documentation.  相似文献   
994.
The solution parameters associated with gradient elution reversed phase high-performance liquid chromatography (HPLC) were characterized by evaluating the electrospray ionization mass spectrometry (ESIMS) response of selected smokeless powder additives. Using direct liquid infusion, the positive ion ESIMS responses were determined for three general classes of powder constituents: dialkylphthalate acid esters, N,N'-dialkyl-N,N'-diphenyl urea based stabilizers and nitroso-, nitro-, and dinitro- derivatives of diphenylamine. The relative ESIMS intensities of the powder components were investigated as a function of three solution parameters: ammonium acetate concentration, pH, and percent methanol. The effect of the ammonium acetate concentration demonstrates that the electrolyte is required for efficient ionization and the ESIMS intensity was optimal at a concentration of 2mM for the selected compounds, except 2,4'-dinitrodiphenylamine. The aqueous solution pH, corresponding to the available protons in solution, did not have a significant effect on the ESIMS intensity of the analytes. The percent methanol was evaluated with both decreasing and constant electrolyte concentrations to demonstrate the effects of droplet stability and ion transfer into the gas phase. These findings were applied to the analysis of the selected smokeless powder additives using HPLC-ESIMS to illustrate increased sensitivity for the protonated molecules.  相似文献   
995.
996.
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed.  相似文献   
997.
Although the topic of recidivism invariably elicits much interest, there appears to be considerable conflict and uncertainty as to even crude estimates of the recidivism rate for persons released from prison. The purpose of this research was to examine the extent to which this apparent confusion may be explained by different methodological choices of criterion measure or length of follow-up. Through the cooperation of the Federal Bureau of Investigation, rap sheet follow-up information for a six-year period was obtained for a relatively large random sample of federal prisoners released in 1970. This data enabled calculation of recidivism rates using various criterion measures and follow-up periods applied to the same sample. The effect of varying these definitions on the recidivism rate obtained can then be directly observed.  相似文献   
998.
999.
Most new retired workers in 1982 owned some type of asset, usually a savings, checking, or credit union account, according to data obtained by the Social Security Administration (SSA) in its New Beneficiary Survey. Many recently retired workers also owned their home, often mortgage-free. Homeownership was their most significant asset in terms of its median value. Comparatively few retirees owned property other than a home, though for owners of such property, the median value was substantial. Married couples, whose assets included those of both partners, more frequently owned assets and their assets had higher median values than did unmarried individuals. A comparison of retired workers with persons aged 65 or older who were enrolled in the Medicare program but who had not yet received retired-worker benefits showed that these Medicare-only enrollees were much better off, both in the likelihood of owning assets and in having higher median values for their assets. Individuals who retired before reaching age 65 and therefore received a reduced social security benefit were not as well off as those whose first benefit was paid at age 65 or older. Overall, the asset situation of new retired workers in 1982 was better than that of men and unmarried women aged 58-63 in 1969, even when the 1969 assets were adjusted to constant 1982 dollars.  相似文献   
1000.
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