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A suicidal poisoning committed by a 61-year-old woman, who ingested an unknown quantity of Killex, containing in aqueous solution 100 g/L of (2,4-dichlorophenox)acetic acid (2,4-D), 50 g/L of mecoprop, and 9 g/L of dicamba as amine salts is described. Quantitation of chlorophenoxy acids was performed by extraction from an acidified mixture and concentration before high performance liquid chromatography analysis. All three herbicides were separated in a phosphate buffer/acetonitrile mixture at 280 nm on a RP-8 column. Concentrations of herbicides found were: in blood--520-mg/L 2,4-D, 530-mg/L mecoprop, and 170-mg/L dicamba; in urine--670-mg/L 2,4-D and 520-mg/L mecoprop; in bile--340-mg/L 2,4-D, 530-mg/L mecoprop, and 140-mg/L dicamba; and in liver--540-mg/Kg 2,4-D, 500-mg/Kg mecoprop, and less than 100-mg/Kg dicamba. Liquid chromatography was found to be a reliable method for herbicide quantitation in biological tissues and fluids. The technique offered definite advantages over ultraviolet spectrophotometry and avoids the derivatization requirement for gas chromatography.  相似文献   
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This study was designed to test the reliability of using the third molars to demarcate between child and adult status. A total of 2000 dental panoramic tomographs were used for assessment of the calculated age using the 8‐stage system of tooth development and applied to all four third molars. The LL8 was also assessed using this 8‐stage system. For each tooth development stage, the Normal distribution and percentile summary data were estimated. The calculated dental age compared with the chronological age was statistically significantly different (p < 0.001) for both females and males giving underestimates of the true age. Comparison of single tooth dental age and chronological age was only slightly different. The most important finding is that the assignment to above or below the 18‐year threshold, in the age range 17 years to 19 years, could be wrong on up to 50% of occasions.  相似文献   
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The objective of this study is to describe a urine drug-testing program implemented for parents with a history of substance abuse by family service agencies in the province of Nova Scotia, Canada. Nurse collectors went to the parents' home to obtain urine specimens under direct observation and then delivered the specimens to the toxicology laboratory or arranged shipment by courier under chain of custody. Each urine specimen was screened for cannabinoids, cocaine metabolite, opiates, amphetamines and benzodiazepines, ethyl alcohol and creatinine. All positive screening tests were confirmed by another method such as gas chromatography-mass spectrometry (GC-MS). In 15,979 urine specimens collected from 1994 to 1999, the percent positive rate for one (or more) drugs/metabolites ranged from 45.6% (1994-1996) to 30.0% (1998, 1999). A total of 575 specimens (3.7%) were dilute (urine creatinine <25mg/dl). Positive rates in 15,404 non-dilute specimens from 1994 to 1999 were as follows: cannabinoids - 11.7%, benzodiazepines - 11.3%, cocaine metabolite - 3.7%, and ethyl alcohol - 2.6%. Most clients provided less than 20 urine specimens for testing but some individuals submitted urine specimens more than 100 times in a 12-15-month period. Urine drug screening in parents with a history of substance abuse provided an objective and reliable indication of recent drug use in this population.  相似文献   
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Exposure to media violence, including violent video gaming, can have a cognitive desensitization effect, lowering empathic concern for others in need. Since emerging adulthood offers increased opportunities to volunteer, strengthen relationships, and initiate new relationships, decreases in empathic concern and prosocial behavior may prove inhibitive to optimal development during this time. For these reasons, the current study investigated associations between violent video gaming, empathic responding, and prosocial behavior enacted toward strangers, friends, and family members. Participants consisted of 780 emerging adults (M age = 19.60, SD = 1.86, range = 18–29, 69% female, 69% Caucasian) from four universities in the United States. Results showed small to moderate effects between playing violent video gaming and lowered empathic concern for both males and females. In addition, lowered empathic concern partially mediated the pathways between violent video gaming and prosocial behavior toward all three targets (at the level of a trend for females), but was most strongly associated with lower prosocial behavior toward strangers. Discussion highlights how violent video gaming is associated with lower levels of prosocial behavior through the mechanism of decreased empathic concern, how this association can affect prosocial behavior differently across target, and finally what implications this might have for development during emerging adulthood.  相似文献   
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ABSTRACT

Developments in the area of ‘precision agriculture’ are creating new data points (about flows, soils, pests, climate) that agricultural technology providers ‘grab’, aggregate, compute and/or sell. Food producers now churn out food and, increasingly, data. ‘Land grabs’ on the horizon in the global south are bound up with the dynamics of data grabbing, although hitherto researchers have not revealed enough about the people and projects at issue. Against this backdrop, this paper examines some key issues taking shape, while highlighting new frontiers for research and introducing the concept ‘data sovereignty’, which food sovereignty practitioners (and others) need to begin considering.  相似文献   
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This article explores the ethnic incorporation of Irish women on the West Coast of New Zealand’s South Island from 1864, when the gold rushes began, until the formation of the Irish Free State in 1922. The central argument is that these newcomers did not choose ethnic solidarity as a means to pursue their goals and, for most, an ethnic or religious category sufficed in an environment where local communities, churches, trade unions, kinship ties and non‐ethnic political parties had far more social relevance. The small‐scale structure of West Coast localities, the relative economic homogeneity of its inhabitants and the absence of entrenched anti‐Irish elites militated against the rise of sectarian animosities and the maturation of intensified ethnic consciousness. As a consequence, Irish women did not construct and sustain informal social networks based on ‘principles of ethnic categorisation’ in which they distributed resources and channelled interaction among group members.  相似文献   
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