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541.
304 postmortem blood samples were serologically examined for syphilis at Statens Seruminstitut. Seventy-six percent of the samples were usable and gave clear-cut results (18% positive, 34% negative and 24% borderline). Twenty-four percent were indeterminable. The blood samples originated from 304 medico-legally examined bodies, 301 of whom were autopsied. The indications for the serological examinations were suspicion of syphilitic aortitis (SA) on the basis of the macroscopical appearance of the aorta at the autopsy--or information on earlier syphilis. Ninety-seven cases of SA were verified macro- and microscopically, 53 being lethal. The serological results were positive in half of these 97 cases, negative in 15, borderline in 21 and indeterminable in 12. A little more than half of the 97 cases were known in advance in the nation-wide syphilis index at the State Serum Institute. The variegated findings in the remaining part of the material are discussed. It is concluded that serological examination of postmortem blood may be a valuable adjuvant for the pathologist for the diagnosis of SA and other syphilitic manifestations.  相似文献   
542.
文章以四川省成都市农村女性劳动力迁移流动情况的抽样调查为基础,通过数据统计描述,归纳四川省农村女性劳动力迁移流动呈现的基本特征及其目前的弱势处境,提出应改革户籍管理制度,强化政府保护农村女性劳动力的职能,加强农村女性的教育和职业技能培训,全面提升农村女性劳动力素质,完善农村社会保障体系,从而促进四川省农村女性劳动力良性迁移流动。  相似文献   
543.
The aim of this study was to investigate the incidence of benzodiazepines in opioid-positive death investigations, including trends in frequency and combination of drugs, as well as demographic data and blood concentrations, where available. Additionally, naloxone concentrations in polysubstance compared to opioid-only cases were analyzed. This was a retrospective study that consisted of all post-mortem toxicology cases in Ontario, Canada, from January 01, 2017, to December 31, 2021, with an opioid finding in any analyzed autopsy specimen. There were 11,033 death investigations identified. The overall rate of benzodiazepine co-involvement was 54.5%. Males accounted for the majority of cases (71%), and the most affected age group was 30- to 39-year-olds. The most frequently detected opioid was fentanyl and the most frequently detected benzodiazepine was etizolam, which was also the most frequently observed opioid/benzodiazepine combination. Findings related to differences in concentrations of opioids when naloxone was also present were mostly non-significant, except for methadone. The rate of benzodiazepine detection with opioids grew faster than opioid detections overall, potentially due to the increasingly toxic drug supply. Detection of novel psychoactive drugs fluctuated more unpredictably than opioids and benzodiazepines associated with clinical use. These findings can help inform policy decisions by public health agencies in exploring harm reduction efforts, for example, education and drug-checking services.  相似文献   
544.
目的:研究脑络欣通对气虚血瘀脑缺血再灌注模型鼠神经细胞凋亡率及N 甲基 D 天冬氨酸受体(NMDAR)蛋白表达的影响.方法:采用饥饿、劳累、高脂饮食等多因素复制大鼠气虚血瘀模型,然后用线栓法阻断大鼠左侧大脑中动脉2 h再灌注6,24,72 h,复制局灶性脑缺血再灌注模型,用流式细胞仪和免疫组化法分别检测缺血半暗带神经细胞凋亡率和NMDAR蛋白表达.结果:与模型组比较,脑络欣通组神经细胞凋亡率和NMDAR蛋白表达显著减少(P<0.01).结论:脑络欣通抑制NMDAR蛋白表达,是其抗脑缺血再灌注后神经细胞凋亡的机制之一.  相似文献   
545.
超高效液相色谱-MS/MS法测定血中11种苯丙胺类物质   总被引:1,自引:1,他引:0  
目的应用超高效液相色谱-质谱法对全血中11种苯丙胺类毒品进行定量测定。方法全血样品经1%(v/v)甲酸-乙腈提取,采用Ostra磷脂过滤板净化处理,使用ACQUITY UPLC BEH Phenyl(100mm×2.1mm,1.7μm)色谱柱,以0.3%(v/v)甲酸溶液-乙腈为流动相进行梯度洗脱。在多反应监测模式下测定全血样本中苯丙胺、甲基苯丙胺、二亚甲基双氧苯丙胺、替苯丙胺、3,4-亚甲基二氧基乙基苯丙胺、N-甲基-1-(3,4-亚甲二氧基苯基)-2-丁胺、副甲氧基甲基苯丙胺、麻黄碱、甲基麻黄碱、卡西酮、甲卡西酮,并进行方法学考察。结果 11种苯丙胺类物质的检出限(S/N≥3)为0.01~0.4ng/m L,在0.5~50μg/L范围内线性关系良好(r0.999);回收率在75.8%~103.4%之间,相对标准偏差在1.6%~13.0%之间。结论本文建立的超高效液相色谱-质谱法快速、简便、灵敏,适用于中毒案件检验及吸毒人员排查。  相似文献   
546.
Suspect hypodermic needles and syringes were seized from an unlicensed individual who was allegedly injecting patients with silicone (polydimethylsiloxane [PDMS]) for cosmetic enhancement. Since control syringe barrels and needles often contain an interfering PDMS lubricant, a risk for false positives of foreign PDMS exists. The focus of this report was to minimize this risk and determine a quick and reliable test for the presence of blood in PDMS matrices. Using ATR‐FT‐IR spectroscopy, the risk for false‐positive identification of foreign PDMS was reduced by (i) overfilling the sampling aperture to prevent spectral distortions and (ii) sampling a region of the suspect syringe/needle assembly where manufacturer‐applied PDMS is not typically located. Analysis for blood indicated that the Teichman microchemical test was effective for detecting blood in the presence of PDMS. Overall, detecting PDMS established intent and detecting blood established that the needle containing the PDMS had been used for injection.  相似文献   
547.
The 1.2 mm Electric Coring Tool (e-Core™) was developed to increase the throughput of FTA sample collection cards used during forensic workflows and is similar to a 1.2 mm Harris manual micro-punch for sampling dried blood spots. Direct short tandem repeat (STR) DNA profiling was used to compare samples taken by the e-Core tool with those taken by the manual micro-punch. The performance of the e-Core device was evaluated using a commercially available PowerPlex™ 18D STR System. In addition, an analysis was performed that investigated the potential carryover of DNA via the e-Core punch from one FTA disc to another. This contamination study was carried out using Applied Biosystems AmpflSTR™ Identifiler™ Direct PCR Amplification kits. The e-Core instrument does not contaminate FTA discs when a cleaning punch is used following excision of discs containing samples and generates STR profiles that are comparable to those generated by the manual micro-punch.  相似文献   
548.
The breath analyzer is an indispensable tool for identifying alcohol levels among drivers. While numerous studies have shown high correlations between blood and breath alcohol concentrations, most are limited by the study design. This study seeks to assess this relationship by minimizing potential measurement bias, document time from alcohol consumption to testing, and adjusting for potential confounders. A blinded study was performed using conditions closely resembling those in the field. The Draeger 7110 MKIII IL breath analyzer was used to assess breath alcohol concentrations (BrAC). Participants were 61 healthy volunteers aged 21–37 years with body mass index ≤30 and no history of alcoholism. A total of 242 valid blood/breath tests were performed in four test sets. The study results showed a high correlation coefficient between BrAC and blood alcohol concentration (BAC) levels (r = 0.983) with high sensitivity (97%) and specificity (93%). This strong association between the breath analyzer and BAC persisted even after adjustment for various stages of alcohol absorption. These results illustrate the high diagnostic sensitivity of the breath analyzer in field‐tested conditions.  相似文献   
549.
The aim of the study is to present the application of a headspace–gas chromatography–mass spectrometry (HS‐GC‐MS) method for the determination of the carbon monoxide (CO) blood concentration and to compare it with carboxyhemoglobin (HbCO) saturation. In postmortem cases, the HbCO measured by spectrophotometry frequently leads to inaccurate results due to inadequate samples or analyses. The true role of CO intoxication in the death of a person could be misclassified. The estimation of HbCO from HS‐GC‐MS CO measurements provides helpful information by determining the total CO levels (CO linked to hemoglobin (HbCO) and CO dissociated from hemoglobin). The CO concentrations were converted in HbCO saturation levels to define cutoff blood CO values. CO limits were defined as less than 1 μmol/mL for living persons, less than 1.5 μmol/mL for dead persons without CO exposure, and greater than 3 μmol/mL for dead persons with clear CO poisoning.  相似文献   
550.
Luminol, Bluestar®, and Hemascein® were tested to compare detection sensitivities to latent blood. Untreated, EDTA‐treated human blood, and a catalytically similar blood substitute were diluted (neat to 1:1,000,000) and pipetted onto a variety of substrates. Luminol and Bluestar® performed similarly on all surfaces and fabrics. Hemascein® yielded poor results on wood surfaces, but performed well in the detection of latent blood on fabrics. Results from untreated, EDTA‐treated, and synthetic blood results indicate that EDTA‐treated blood is similar or slightly less sensitive than untreated blood at all dilutions and on all substrates, and the synthetic blood is less sensitive than real blood, but consistent in detection threshold and thus is useful as a training aid. Additionally, some foods and household chemicals that have previously been shown to cross‐react were tested with Bluestar®, Hemascein®, and luminol. Hemascein® cross‐reacted with many substances, while both luminol reagents were more discriminating.  相似文献   
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