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181.
A plastic syringe containing bloody fluid, 2 ampules of 20% glucose, an ampule containing diphenhydramine hydrochloride and calcium bromide, powder in a plastic bag and powder wrapped in paper were among the articles found in the possession of a 42-year-old male methamphetamine abuser, who had been taken to a mental hospital owing to his hallucinations.Examination of the patient revealed several recent needle punctures on the left forearm. The concentration of methamphetamine and its metabolite, amphetamine, in blood collected 1 day following the last intake was 76 nmol/100 g. Analysis of the powder and of the contents of the syringe revealed methamphetamine hydrochloride at a concentration of 99.0–99.5% and 7.4%, respectively. Neither glucose nor diphenhydramine were detected in the contents of the syringe.It would seem that the patient abused methamphetamine hydrochloride by intravenous injection after dissolving it in city water or distilled water.  相似文献   
182.
大鼠死后心血吗啡浓度变化的HPLC检测   总被引:1,自引:0,他引:1  
采用高效液相邑谱分析技术(HPLC)检测治疗量及中毒量吗啡肌注大鼠死后心血中吗啡浓度变化。结果表明,以治疗量吗啡肌往大鼠,在死后96h内,心血中吗啡浓度随死后时间增加而显著升高(P<0.01),吗啡浓度水平与死后时间里显著正相关;以中毒量吗啡肌注大鼠,在死后12h内,心血吗啡浓度无明显变化;死后24h、48h及96h,随死后时间延长,心血中吗啡浓度逐渐升高(P>0.01),其递增强度不如治疗量吗啡组大鼠的明显.本研究证实,死后尸体心血吗啡浓度明显受生前剂量的影响,且在死后96h内,随死后时间增加.心血中吗啡浓度少数不断增高。  相似文献   
183.
本文报道了对硫磷(1605)中毒后其代谢产物氨基对硫磷的测定方法。检材中的氨基对硫磷经有机溶剂提取,用气相色谱(NPD)测定,在肝或血中的回收率皆在70%以上。本法适用于腐败组织中以检测氨基对硫磷来确定1605中毒。  相似文献   
184.
采用同时裂解甲基化气相色谱法(SPM-GC),首次分析人体脂肪,并且观察人体脂肪、猪、鸡、牛、羊脂和豆油中7种脂肪酸的组份含量变化。根据7种主要脂肪酸(肉豆蔻酸、棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸和亚麻酸)甲酯的百分含量可有效地进行鉴别。结果表明:通过SPM-GC法分析油脂,可将传统的油脂酯化法时间由2个多小时缩短到1分钟左右。数据C.V.%<4%,最小检测量为1.Oμg。最佳比例四甲基氢氧化按(TMAH)甲醇液(TMAH:甲醇=1:10,V/V),可消除油脂中多不饱和脂肪酸的异构化和降解。  相似文献   
185.
吩噻嗪类安眠镇静药物易受光、热分解,气相色谱分析法受一定限制。而采用反相离子对液相色谱技术,使七种常见吩噻嗪类药物得到较好的分离。使用紫外及荧光分光光度计测定,可作为血、尿中此类药物的快速定性、定量分析方法之一。本法已在刑事中毒案件与临床抡救化验中应用。  相似文献   
186.
Bu J  Yan L  Chen Y  Chu JX  Xie XF  Chen TP 《法医学杂志》2001,17(1):21-24
对 4年间 6家医院所有门急诊有关敌敌畏、甲胺磷、乐果三种有机磷农药中毒病例进行了调查分析。运用气相色谱法对其血液中的浓度进行测定。采用 Bliss法,计算其死亡率和昏迷率的加权直线回归方程,并获得其经救治后血液半数致死浓度 LC50、半数致昏迷浓度 CC50。综合文献和临床实践,认为及时的救治对中毒病例的治疗转归有较大影响,其自然的血液半数致死浓度应在经救治的半数致死浓度 LC50和半数致昏述浓度之间。综合半数致死浓度和半数致昏迷浓度,计算其自然的半数致死浓度 LCe50值。  相似文献   
187.
Analysis of impurities in methamphetamine (MA) can be used to characterize MA seizures, investigate the relationship among MA seizures, and provide information on their synthetic routes. Recently, chemically derivatized MA, such as tert-butoxycarbonyl (t-Boc) MA, has been seized and attracted attention because routine forensic analysis methods may fail to correctly identify them. Chemical derivatization is a simple method for protection and deprotection of a compound, and protection of MA using t-Boc can be used to mask the MA. Although t-Boc derivatization might alter the impurity profile of MA, the actual changes in the impurity profile have not been investigated. In this study, changes in the MA impurity profile with tert-butoxycarbonylation were explored. MA and some typical impurities were derivatized using di-tert-butyl dicarbonate and water. Analysis of the impurities in five MA samples by gas chromatography showed that peaks both appeared and disappeared for the deprotected MA compared with the original MA. However, typical impurities important for characterizing MA seizures were conserved after derivatization and deprotection. Most of the new peaks were speculated to be contaminants introduced during derivatization and deprotection. A peak giving a mass spectrum similar to that of t-Boc MA was detected in the chromatograms of t-Boc MA and deprotected MA. Although the origin of this peak was not determined, it might be a marker for the MA involving tert-butoxycarbonylation. These results indicate that tert-butoxycarbonylation can alter the MA impurity profile; therefore, care is needed when interpreting results for derivatized MA.  相似文献   
188.
《Science & justice》2021,61(6):697-703
The identification and confirmation of trace explosive residues along with potential precursors and degradation products require a comprehensive laboratory analysis procedure. This study presents the determination of organic explosives consisting of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,4,6-trinitrotoluene (TNT), 2,4,6,N-tetranitro-N-methylaniline (Tetryl), 1,3,5-trinitrobenzene (1,3,5-TNB) and pentaerythritol tetranitrate (PETN) by a high-resolution liquid chromatography quadrupole time-of-flight mass spectrometry (LC−QTOF/MS). The qualitative information including retention time, collision energy, precursor ions, and characteristic fragmentation pattern of each explosive were collected using an atmospheric pressure chemical ionization (APCI) in negative ion mode. The separation efficiency among five compounds was greatly achieved in this study. Four real explosive samples consisting of TNT, RDX, PETN and Tetryl and 12 Ionscan® quality control swabs from the Royal Thai Army were also tested to validate and verify the viability of the GC–MS method used to validate results from an Ionscan® system. The results showed that LC−QTOF/MS is a powerful technique for the identification and confirmation of thermally unstable organic explosives on Ionscan® swabs compared to a conventional GC−MS technique.  相似文献   
189.
Studying links between triacetone triperoxide (TATP) samples from crime scenes and suspects can assist in criminal investigations. Isotope ratio mass spectrometry (IRMS) and gas chromatography (GC)‐IRMS were used to measure the isotopic compositions of TATP and its precursors acetone and hydrogen peroxide. In total, 31 TATP samples were synthesized with different raw material combinations and reaction conditions. For carbon, a good differentiation and a linear relationship were observed for acetone–TATP combinations. The extent of negative (δ13C) fractionation depended on the reaction yield. Limited enrichment was observed for the hydrogen isotope (δ2H) values of the TATP samples probably due to a constant exchange of hydrogen atoms in aqueous solution. For oxygen (δ18O), the small isotopic range and excess of water in hydrogen peroxide resulted in poor differentiation. GC‐IRMS and IRMS data were comparable except for one TATP sample prepared with high acid concentration demonstrating the potential of compound‐specific isotope analysis. Carbon IRMS has practical use in forensic TATP investigations.  相似文献   
190.
为了研究喹烯酮在鱼体内的药物代谢动力学及组织分布情况,在(15±1)℃的水温条件下,按50mg/kg单剂量口服给药后,采用高效液相色谱法测定喹烯酮在鲤、斑点叉尾鮰血浆与组织中的药物浓度.结果,喹烯酮在鲤和斑点叉尾鮰体内的药代动力学模型均符合两室开放模型.喹烯酮在鲤血液中2 h时达到最高血药浓度(Cmax)为0.452 μg/mL,在肝、肾、肌肉组织中达峰时间分别为8、16和16 h,主要药代动力学参数t1/2(ka)、t1/2β、AUC分别为1.263 h、35.866 h、24.585(μg/mL)·h;喹烯酮在癍点叉尾鮰血液中8 h达到最高血药浓度(Cmax)为0.029μg/mL,在肝、肾、肌肉组织中达峰时间分别为16、48和72 h,主要药代动力学参数t1/2(ka)、t1/kβ、AUC分别为4.669 h、31.164 h、1.388(μg/mL)·h.结果表明,喹烯酮在鲤与斑点叉尾鮰体内吸收较快,分布较广,主要经肝、肾代谢.  相似文献   
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