全文获取类型
收费全文 | 973篇 |
免费 | 80篇 |
专业分类
各国政治 | 108篇 |
工人农民 | 68篇 |
世界政治 | 120篇 |
外交国际关系 | 48篇 |
法律 | 549篇 |
中国政治 | 2篇 |
政治理论 | 158篇 |
出版年
2023年 | 20篇 |
2022年 | 6篇 |
2021年 | 26篇 |
2020年 | 30篇 |
2019年 | 39篇 |
2018年 | 68篇 |
2017年 | 90篇 |
2016年 | 59篇 |
2015年 | 53篇 |
2014年 | 54篇 |
2013年 | 157篇 |
2012年 | 49篇 |
2011年 | 38篇 |
2010年 | 18篇 |
2009年 | 11篇 |
2008年 | 35篇 |
2007年 | 36篇 |
2006年 | 36篇 |
2005年 | 34篇 |
2004年 | 40篇 |
2003年 | 43篇 |
2002年 | 34篇 |
2001年 | 20篇 |
2000年 | 15篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1972年 | 2篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有1053条查询结果,搜索用时 15 毫秒
991.
Gamma-hydroxybutyric acid (GHB) can cause problems in interpretation of toxicological findings due to its endogenous nature, significant production in tissues after death and potential formation in stored samples. Our study was designed to determine the influence of storage conditions on GHB levels and its possible in vitro formation in blood and urine in cases where no exogenous use of GHB or its precursors was suspected. The samples were prepared by validated method based on liquid-liquid reextraction with adipic acid internal standard and MSTFA derivatization and assayed on a GC-MS operating in EI SIM mode. The first part of the study was performed with pooled blood and urine samples obtained from living and deceased subjects stored with and without NaF (1% w/v) at 4 and -20 degrees C over 8 months. In ante-mortem samples (both blood and urine) no significant GHB production was found. After 4 months of storage, the substantial GHB rise up to 100 mg/Lwas observed in post-mortem blood stored at 4 degrees C without NaF with subsequent gradual decrease in following months. The inhibition of GHB production was apparent during storage in NaF treated frozen blood samples. In post-mortem urine only slight temporary GHB levels were ascertained (up to 8 mg/L). The second part of our study was aimed to analyse 20 individual post-mortem blood samples stored at 4 degrees C for 16-27 days between autopsy and analysis without preservation followed by storage at 4 degrees C with NaF for 4 months. The temporary GHB production with maximum of 28 mg/Lwas detected in some samples. 相似文献
992.
993.
Economists have always criticized politicians' behaviour. Adam Smith called politicians
“crafty and insidious"; and, more recently Brennan and Buchanan have applied Gresham's law to politics, arguing that the man
for whom the expected profit is highest will be the highest bidder for political power. However in their model there is not
an argument to explain why these people are elected to public offices.
This paper presents a supply model and a demand model explaining why politicians behave as
“wicked" men, and are elected by the citizens. Firstly, we develop a model of repetitive and reputation games that shows why
probity is not important for many politicians. The second model employs asymmetric information theory to explain why voters
elect “wicked" people even if probity is a highly estimated value for them. The paper ends with some suggestions of legal
reforms for reducing this asymmetry of information.
classification D72. D82 相似文献
994.
A simple and reliable gas chromatographic method with nitrogen-phosphorus detection without derivatization was developed for the detection of several psychiatric drugs in whole blood as part of systematic toxicological analyses (STA). Drugs included mirtazapine, chlorpromazine, methotrimeprazine (levomepromazine), clothiapine, olanzapine, clozapine, haloperidol, and thioridazine. All drugs were studied at concentrations of 100-2,000 microg/L, except haloperidol that was studied at concentrations of 400-8,000 microg/L. In order to select the best blood purification procedure and therefore increase the signal to noise ratio we have compared two solid-phase extraction (SPE) columns, Chem Elut and Bond Elut Certify, for their recovery, precision, sensitivity and matrix purification efficiency. Recoveries for these drugs using Chem Elut columns at 500 and 2,000 microg/L (2,000 and 8,000 microg/L for haloperidol) were in the range 21-65%, with intra-assay and inter-assay precisions of less than 17% and 19%, respectively. Limits of detection (LODs) and limits of quantitation (LOQs) for mirtazapine, chlorpromazine, methotrimeprazine, clothiapine, olanzapine, clozapine, and thioridazine ranged from 62 to 161 microg/L and from 205 to 531 microg/L, respectively. LOD and LOQ for haloperidol were 442 and 1,458 microg/L, respectively. Recoveries of these compounds using Bond Elut Certify columns at 500 and 2,000 microg/L (2,000 and 8,000 microg/L for haloperidol) were in the range 44-97%, with intra-assay and inter-assay precisions of less than 7% and 14%, respectively. LODs and LOQs for mirtazapine, chlorpromazine, methotrimeprazine, clothiapine, olanzapine, clozapine, and thioridazine ranged from 37 to 66 microg/L and from 122 to 218 microg/L, respectively. LOD and LOQ for haloperidol were 156 and 515 microg/L, respectively. Linearity was observed in the studied range for all compounds with r(2) values of >0.999. The use of the mixed-mode bonded-silica Bond Elut Certify columns showed advantages comparing with Chem Elut columns for the screening of these psychotropic agents such as higher recoveries, cleaner extracts, better sensitivity, better precision and less solvent consumption and subsequent disposal. 相似文献
995.
Hair analysis for drugs has been developing and is considered a significant tool for distinguishing between recent and long-term drug abuse in forensic and clinical toxicology. Chronic consumption of drugs can gradually induce certain harmful effects on the human organism and can exacerbate some pre-existing diseases. Analysis for drugs in blood or urine in isolation does not provide sufficient information about the history of drug-use by a person and their results cannot be correlated directly with the toxic effects displayed. The chronic abuse of methamphetamine is known to be associated with cardiovascular diseases. During or after autopsy certain types of morphologic alterations are found in the hearts of stimulant addicts. The rapid increase in blood pressure after an intravenous methamphetamine dose can be risky for addicts with arteriosclerosis. However, the anamnestic data about a deceased person may not always be available to explain the pathological findings and to classify the cause of death correctly. The aim of this study was to demonstrate the value of hair analysis for drugs in the context of explaining pathological cardiovascular alterations observed during the autopsy in a case where methamphetamine consumption was involved. In this case, only methamphetamine and metabolites were detected with traces of ephedrine. Ephedrine is the precursor chemical in the illicit synthesis of methamphetamine (known in the Czech Republic as "Pervitin"). The femoral blood level of methamphetamine was 1500 ng/ml. It was documented by a witness that the 31-year-old man died within 1h after an intravenous injection of the drug. The cause of death was established as cerebral edema due to cerebellar bleeding shortly after an intravenous dose of methamphetamine. Findings of methamphetamine in the first three 2-cm hair segments (numbered from the roots) were nearly equal (132+/-9 ng/mg). In the fourth 2-cm segment, it was approximately one-half of previous values. In the remaining, distal 7-cm hair segment sample, the value of methamphetamine was higher and comparable to the third segment. These results provide clear evidence that the man had been a chronic methamphetamine abuser for more than 8 months. This information can help to explain the pathology, the consequence of which could be the bleeding into the cerebellum after the last single methamphetamine dose. 相似文献
996.
Brion M Dupuy BM Heinrich M Hohoff C Hoste B Ludes B Mevag B Morling N Niederstätter H Parson W Sanchez J Bender K Siebert N Thacker C Vide C Carracedo A 《Forensic science international》2005,153(2-3):103-108
A collaborative study was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the performance of Y-chromosome binary polymorphism analysis in different European laboratories. Four blood samples were sent to the laboratories, to be analysed for 11 Y-chromosome single nucleotide polymorphisms (SNPs): SRY-1532, M40, M35, M213, M9, 92R7, M17, P25, M18, M153 and M167. All the labs were also asked to submit a population study including these markers. All participating laboratories reported the same results, indicating the reproducibility and robustness of Y-chromosome SNP typing. A total of 535 samples from six different European populations were also analysed. In Galicia (NW Spain) and Belgium, the most frequent haplogroup was R1b*(xR1b1,R1b3df). Haplogroup F*(xK) is one of the most frequent in Austria and Denmark, while the lowest frequency appear in Belgium. Haplogroup frequencies found in this collaborative study were compared with previously published European Y-chromosome haplogroup data. 相似文献
997.
Postmortem vitreous humor beta-hydroxybutyrate: its utility for the postmortem interpretation of diabetes mellitus 总被引:1,自引:0,他引:1
Osuna E Vivero G Conejero J Abenza JM Martínez P Luna A Pérez-Cárceles MD 《Forensic science international》2005,153(2-3):189-195
Ketoacidotic coma is one of the most serious complications arising from diabetes mellitus, especially type I, and may be the cause of sudden death especially in diabetes type I. Since beta-hydroxybutyrate (beta-OHB) serum concentrations might provide more information on the severity of ketoacidosis, the aim of this study was to evaluate the concentrations of beta-OHB in vitreous humor and its correlation with other biochemical parameters during postmortem examination. We intended to ascertain the sensitivity and the specificity of these markers for diagnosing diabetes mellitus and the presence of ketoacidosis. This study involved 453 cadavers with a mean age of 57.6 years (S.D. 20.7) and a mean postmortem interval of 17.8 h (S.D. 9.6, range 2-61 h). Cases were assigned to two diagnostic groups according to the antemortem diagnosis of diabetes mellitus, based on the patients' medical records. In vitreous humor statistically significant differences were found in biochemical marker concentrations between the two diagnostic groups, the highest values being obtained in the group of subjects with a previous diagnosis of diabetes mellitus. The measurement of beta-OHB in vitreous humor may be a useful alternative to using blood during postmortem analysis. The presence of high levels of beta-OHB may help interpret the cause of death in diabetics when the autopsy result is negative. 相似文献
998.
SNPs in forensic genetics: a review on SNP typing methodologies 总被引:17,自引:0,他引:17
There is an increasing interest in single nucleotide polymorphism (SNP) typing in the forensic field, not only for the usefulness of SNPs for defining Y chromosome or mtDNA haplogroups or for analyzing the geographical origin of samples, but also for the potential applications of autosomal SNPs. The interest of forensic researchers in autosomal SNPs has been attracted due to the potential advantages in paternity testing because of the low mutation rates and specially in the analysis of degraded samples by use of short amplicons. New SNP genotyping methods, chemistries and platforms are continuously being developed and it is often difficult to be keeping up to date and to decide on the best technology options available. This review offers to the reader a state of the art of SNP genotyping technologies with the advantages and disadvantages of the different chemistries and platforms for different forensic requirements. 相似文献
999.
Suraje?DessaiEmail author E.?Lisa?F.?Schipper Esteve?Corbera Bo?Kjellén María?Gutiérrez Alex?Haxeltine 《International Environmental Agreements: Politics, Law and Economics》2005,5(2):105-124
From 1 to 12 December 2003, the Ninth Session of the Conference of the Parties to the United Nations Framework Convention took place in Milan, Italy. This conference continued the laborious effort of developing an international climate regime by preparing for the Kyoto Protocol’s entry into force. Some two dozen decisions were adopted on a wide range of options for responding to climate change. This paper assesses the progress achieved at the conference on a number of issues. Among these were operational details for implementing forestry projects under the Convention’s Clean Development Mechanism, and guidelines for reporting on greenhouse gas emissions and removals from agriculture, forestry and land-use change. Parties also decided on rules with respect to two funds, the Special Climate Change Fund and the Least Developed Country Fund. With respect to developing countries, Parties continued discussions on rules for building response capacity in light of the expected adverse effects of climate change and transferring environmentally sound technology. They also discussed how to incorporate scientific advice from the Third Assessment Report of the Intergovernmental Panel on Climate Change into the negotiations. Although Russia did not ratify the Kyoto Protocol prior to the conference, Milan demonstrated momentum and interest among Parties to support the climate regime. Nevertheless, it is doubtful whether the detailed discussions were able to contribute to preparing for the long term. To this end, this paper concludes that more discussion and leadership is required to bridge the North/South gap if a post-2012 climate regime is to stand. 相似文献
1000.
Nikolaos Georgantzís Gerardo Sabater-Grande 《European Journal of Law and Economics》2002,14(2):129-150
We review the decision by the European Commission in the case of the UK Agricultural Registration Exchange. We propose a theoretical model, offering a basis for some of the intuitive arguments used by the Commission on the anti-competitive role of information exchange in the case of price and non price collusion. Market transparency on non price data is shown to be a collusion facilitating device which may achieve stability in otherwise unstable cartels. 相似文献