全文获取类型
收费全文 | 390篇 |
免费 | 20篇 |
专业分类
各国政治 | 36篇 |
工人农民 | 38篇 |
世界政治 | 33篇 |
外交国际关系 | 20篇 |
法律 | 191篇 |
中国政治 | 7篇 |
政治理论 | 82篇 |
综合类 | 3篇 |
出版年
2023年 | 2篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2019年 | 10篇 |
2018年 | 11篇 |
2017年 | 16篇 |
2016年 | 15篇 |
2015年 | 10篇 |
2014年 | 7篇 |
2013年 | 54篇 |
2012年 | 15篇 |
2011年 | 11篇 |
2010年 | 7篇 |
2009年 | 10篇 |
2008年 | 10篇 |
2007年 | 18篇 |
2006年 | 13篇 |
2005年 | 11篇 |
2004年 | 12篇 |
2003年 | 12篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 9篇 |
1999年 | 9篇 |
1998年 | 4篇 |
1997年 | 9篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 10篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 11篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 6篇 |
1983年 | 7篇 |
1982年 | 4篇 |
1981年 | 5篇 |
1979年 | 6篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1968年 | 2篇 |
1964年 | 1篇 |
排序方式: 共有410条查询结果,搜索用时 8 毫秒
311.
A commercially available enzyme-linked immunosorbant assay (ELISA) was evaluated as a screening procedure for the detection of nine classes of abused drugs in postmortem blood and tissue specimens. Specifically, postmortem blood, fluid and/or tissue homogenates were screened for amphetamine (AMP), methamphetamine (MET), barbiturates (BARB), benzodiazepines (BZD), cannabinoids (CNB), cocaine (benzoylecgonine; BE), morphine-specific (MOR), opiates (class; OPI), phencyclidine (PCP) and lysergic acid diethylamide (LSD) by ELISA and by coated tube radioimmunoassay (CTR) (BARB, BE, OPI, PCP, LSD) or double-antibody radioimmunoassay (DAR) (AMP/METH, BZD, CNB). Specimens that screened 'positive' by any method were confirmed and quantitated by gas chromatography/mass spectrometry (GC/MS). The only assay that appeared to perform less optimally than RIA was the MOR assay (five false negatives). However, this assay is very specific for free morphine while the GC/MS confirmation method provided a total morphine value. The OPI assay was more sensitive, producing fewer false negatives, and is recommended for broad class opiate screening. EIA is an adequate alternative to RIA for screening postmortem specimens, including blood and tissue, for nine major classes of drugs. 相似文献
312.
In January of 1999, leading negotiation scholars and practitioners gatheredat Northwestern University for a conference sponsored by the HewlettFoundation. Here, we chronicle a conversation that occurred regardingnegotiation research. Our diverse group consisted of people with backgroundsin social psychology, anthropology, sociology, and clinical practice.We discussed issues surrounding where research takes place (in the lab orin the field), experimental participants (students or practicing professionals),and the ultimate value of research. 相似文献
313.
314.
315.
316.
Aggregate pooled cross-sectional and time-series annual state data for 1985 to 1992 were used to estimate the systemwide effects of retrospective drug utilization review programs (Retro-DUR) on Medicaid drug and nondrug outcomes. The results provide evidence that these programs produce significant cost savings in the drug budget without spillover effects (positive or negative) in other nondrug budgets within the Medicaid system. We also examine the influence of restricted formularies in this post-Retro-DUR era on drug and nondrug budgets in the Medicaid system; we find significant cost savings in the former but positive spillover effects in the latter. 相似文献
317.
Differences in environmental perspectives between advanced industrial and developing country nationals has both practical and policy implications for the transfer of environmentally sound technologies. This paper characterizes rural Senegalese environmental perspectives in the context of competing environmental paradigms and of their historical development. Methodological issues concerning the adaptation of items from the Health of the Planet Survey (HOPS) questionnaire (Dunlap, Gallup, and Gallup, 1993) to rural Senegal are discussed and qualitative survey results presented. Based on a stratified national sample of rural Senegalese men and women, a quantitative analysis addresses the priority concerns of rural Senegalese men and women and how they perceive the trade off between environmental protection and economic development. The paper concludes that attempts to draw valid conclusions concerning comparisons between the environmental perspectives of the publics of advanced industrial and low income developing countries must take local conditions, their historical dynamics and cultural expressions into account. 相似文献
318.
319.
320.
Rocio B. Potoukian BS Jennifer Gonyea BS Elisa N. Shoff BS George W. Hime BS Diane M. Moore PhD 《Journal of forensic sciences》2023,68(6):2205-2210
Xylazine sedative, muscle relaxant, and analgesic used in a veterinary setting. Although xylazine was never approved for therapeutic use in humans, it has become popular in the street drug market as a cutting or bulking agent in the fentanyl and heroin supply. Recently, there has been a significant increase in the detection of xylazine in postmortem forensic toxicology casework. Xylazine can be identified during routine toxicology screening utilizing instrumentation such as gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry. Using the Miami-Dade Medical Examiner's LIMS system, all cases received between 2015 and 2022 in which xylazine was reported were reviewed. The cases studied include accidental drug overdose deaths in Miami-Dade County as well as Collier County (Naples), Florida. In total, there are 170 cases; the majority are accidental polydrug overdoses involving White males between the ages of 25 and 44 years old. Of the 170 cases, 37% listed xylazine as the cause of death. 13% of cases contained only xylazine and fentanyl while the remaining 87% of deaths were attributed to polydrug toxicity involving two or more substances. The prevalence of xylazine can be attributed to its increasing popularity rather than an increase in caseload. In 2019, xylazine was present in only 4% of all accidental fentanyl overdoses. By 2021, this percentage has increased sixfold, with xylazine present in 24% of all accidental fentanyl overdoses. Despite a decrease in fentanyl overdoses in 2022, the percentage of xylazine detection remained the same. 相似文献