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961.
Spectra interference between diquat and paraquat by second derivative spectrophotometry 总被引:1,自引:0,他引:1
A rapid and accurate method, combining solid-phase extraction and second-order derivative spectrophotomety approaches, is developed for the simultaneous determination of diquat (DQ) and paraquat (PQ) in blood, tissue and urine samples. Supernatant resulting from the precipitation of protein (with trichloroacetic acid) in plasma and tissue or Amberlite IRA-401 resin treated urine are passed through a mini-column packed with Wakogel gel (Silica gel). Analytes are then eluted with a non-organic solvent, 0.2mol/l HCl solution containing 2mol/l NH(4)Cl. UV spectrum of the eluent in 220-350nm range provides effective screen to detect the presence of DQ and/or PQ. In the presence of DQ or PQ alone, the analyte present is quantitated by conventional zero- or second-order derivative spectrophotometry. The calibration curve in the 0.1-5.0mg/l range for either analyte obeys Beer's law. When both DQ and PQ are present, their concentrations are determined by the peak amplitudes of their respective second-derivative spectra after the addition of alkaline dithionite reagent. Interference is negligible when the DQ/PQ concentration ratio is within the 5.0-0.2 range.Using a 2-ml of sample size, the detection limits for DQ and PQ in plasma are 0.02 and 0.005mg/l. The corresponding detection limits for urine samples (10ml sample size) are 0.004 and 0.001mg/l. Recoveries of DQ and PQ in triplicate plasma and urine samples spiked with 0.5mg/l of analytes are 93 and 85%. The precision of the proposed method resulting from triplicate study of spiked urine samples varies from 3.2 to 4.6% at 0.5mg/l of DQ and PQ, respectively. 相似文献
962.
This study examines the effects of profound hypothermia on the blood-brain barrier (BBB) permeability in ethanol administrated rats. Vascular permeability to intravenously injected Evans blue (EB) was quantitatively examined in the brain regions of rats. Rats were treated with ethanol acute and chronically. Rectal temperature of rats was dropped into 20+/-1 degrees C during profound hypothermia. Mean arterial blood pressure in both acute and chronic ethanol treatments plus hypothermia significantly dropped into low levels as well as in hypothermia alone (P<0.01). Hypothermia led to a significant increase in the content of EB dye in the brain regions of rats (P<0.05). Both acute and chronic ethanol treatments plus hypothermia did not lead to a significant increase in the BBB permeability against intravenously injected EB dye. We conclude that ethanol intake protects the BBB against the effects of hypothermia. 相似文献
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965.
赵清城 《中共福建省委党校学报》2001,(7):3-7
对领导干部的日常管理和监督是党要管党、落实"三个代表"的基本要求,是强化党内监督的需要.要按照干部管理权限,加强上级党组织、组织部门、纪检监察机关和同级党组织的监督,把干部的管理和监督落实到具体工作中. 相似文献
966.
赵剑眉 《辽宁公安司法管理干部学院学报》2001,(Z1):21-22
"三个代表"思想是国际共产主义运动150年和我党80年历史经验的总结,也是党的三代领导核心对自身命运进行哲学思考的理论成果. 相似文献
967.
In many countries, including the United States, the number of persons being awarded long-term or permanent disability benefits has risen dramatically in recent years. Government agencies, advocates for the disabled, and others are looking for ways to help persons with disabilities return to the labor force. The Work Incapacity and Reintegration (WIR) Study was developed to address that issue. The United States and five other countries--Germany, Denmark, Sweden, Israel, and the Netherlands--have participated in a cross-national study of work incapacity under the auspices of the International Social Security Association. The study had two objectives: to examine the factors that influence the pattern of work resumption among persons disabled by a back condition and to identify the medical and nonmedical interventions that are most effective in helping such persons reenter the labor force. Samples for the U.S. national study were drawn from four cohorts: Social Security Disability Insurance (DI) beneficiaries, Supplemental Security Income (SSI) beneficiaries, and recipients of temporary disability insurance (TDI) benefits from the states of California and New Jersey. Only the TDI recipients were included in the comparative study. This article discusses the study design and methodology and summarizes the findings of the U.S. national study. Findings from the U.S. study show significant differences between the two cohorts in terms of work resumption and other characteristics. The proportions of respondents from the TDI cohorts who were working at the third and final study contact ranged from 53 percent to 65 percent, compared with less than 5 percent of the DI and SSI respondents. Respondents from the DI and SSI cohorts were on average about 10 years older than the TDI respondents, were less well educated, and reported more physical demands in their usual work. They also reported lower levels of functional capacity, higher levels of pain, and a much greater tendency to have other chronic illnesses. The types of medical treatments provided were remarkably uniform across cohorts and, within cohorts, between those who did and did not resume working. Thus, no medical intervention was identified that showed a significantly higher success rate in terms of facilitating a return to work. However, changes made in the work environment by the employer were an important factor in work reintegration; about 80 percent of respondents who resumed working did so with the help of workplace accommodations. In addition, since respondents with fewer physical demands in their job were more likely to return to work, there appears to be some potential for job retraining as a means of promoting a return to work. The Social Security Administration should consider these findings in developing strategies to help disabled workers reenter the labor force. 相似文献
968.
This article analyzes the impact of policy variables--employer accommodations, state Social Security Disability Insurance (DI) allowance rates, and DI benefits--on the timing of an application for DI benefits by workers with a work-limiting health condition starting when their health condition first begins to bother them. The analysis uses a rich mixture of personal and employer characteristics from the Health and Retirement Study linked to Social Security administrative records. We find that most workers do not apply immediately for DI benefits when they are first bothered by a health condition. On the contrary, the median working-age man with a work-limiting condition waits 7 years after that time before applying, and the median working-age woman waits 8 years. Although the risk of applying for benefits is greatest in the year following onset, only 16 percent of men and 13 percent of women in our sample apply within the first year, and the risk of application falls thereafter. That finding suggests that institutional factors, in addition to health factors, may play a role in the timing of DI applications. Using kernel density estimates of the distribution of application and nonapplication ordered by state allowance rates (the rate of acceptance per DI determination in each state), we find that both men and women who live in states with high allowance rates are disproportionately more likely to apply for benefits in the first year after their condition begins to bother them than are those in states with low allowance rates. Using life-table analysis, we also find that men and women who are accommodated by their employers are significantly less likely to apply for DI benefits in each of the first few years after their condition begins to bother them than are those who are not accommodated. On the basis of this evidence, we include these policy variables in a model of the timing of DI application that controls for other socioeconomic variables as well as health. Using a hazard model, we find that workers who live in states with higher allowance rates apply for DI benefits significantly sooner than those living in states with lower allowance rates following the onset of a work-limiting health condition. Workers who are accommodated following the onset of a work-limiting health condition, however, are significantly slower to apply for DI benefits. Using the mean values of all explanatory variables, we estimate the relative importance of changes in these policy variables on the speed with which workers apply for benefits after onset. We find that the mean time until application for men is 10.22 years. Universal accommodations following onset would delay application by 4.36 years. In contrast, a 20 percent decrease in state allowance rates would delay application by only 0.88 years. For working-age women, the average expected time until application once a condition begins to bother them is 10.58 years. Universal accommodations would delay that by 3.76 years, and a 20 percent decrease in allowance rates would delay it by 1.47 years. A complication in this analysis is that the policy variables are to some degree endogenous. Accommodation is probably offered more often to workers who want to continue working. Allowance rates are chosen by states on the basis of federal policy and local choices and probably in part on the health condition of workers in the state. Therefore, our estimates are upper bounds of these policy effects. Still, we believe we provide evidence that the social environment faced by workers with work-limiting health conditions can significantly influence their decision to apply for DI benefits, holding their specific health conditions constant. 相似文献
969.
970.
赵树槐 《河北公安警察职业学院学报》2001,1(2):8-10
为实践"三个代表"的重要思想,实现国家长治久安,要不断改造自己的世界观,树立一切权力来源于人民的权力观.权力必须服务于人民,必须为人民掌好权;要正确对待和行使权力,要仰角做事,俯首为民;要克已奉公,不谋私利;要经受考验,过好"三关";要体察民情,为民排忧.权力必须受到全方位多种形式的监督. 相似文献