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排序方式: 共有5519条查询结果,搜索用时 218 毫秒
61.
Ariadne Malamitsi-Puchner 《The journal of maternal-fetal & neonatal medicine》2017,30(2):141-143
This report refers to preterm birth in Ancient Greece based on mythological, historical and archeological data. The two antique goddesses, patronesses of labor and birth, Artemis and Eileithyia, cared for full-term, as well as preterm infants, among them for the mythological preterms Dionysos and Eurystheus. The former was rapidly transported by Hermes and received special care by the nymphs Hyades in a mountain cave with “incubator” properties. Historical data are related to the nine months duration of a normal pregnancy, to the definition of “Elitomina” (preterms), the lower limit of viability, the causes for preterm birth, the existence of small for gestational age infants and relevant causes, the physical examination of neonates and postpartum care. Lastly, excavations in Athens and Astypalaia discovered burials – in wells or pots – of preterm infants with gestational age 24–37 weeks. 相似文献
62.
Human cytochrome P450 2C9 (CYP2C9) accounts for ∼20% of hepatic total CYP content and metabolizes ∼15% clinical drugs such as phenytoin, S-warfarin, tolbutamide, losartan, and many nonsteroidal anti-inflammatory agents (NSAIDs). CYP2C9 is highly polymorphic, with at least 33 variants of CYP2C9 (*1B through *34) being identified so far. CYP2C9*2 is frequent among Caucasians with ∼1% of the population being homozygous carriers and 22% are heterozygous. The corresponding figures for the CYP2C9*3 allele are 0.4% and 15%, respectively. There are a number of clinical studies addressing the impact of CYP2C9 polymorphisms on the clearance and/or therapeutic response of therapeutic drugs. These studies have highlighted the importance of the CYP2C9*2 and *3 alleles as a determining factor for drug clearance and drug response. The CYP2C9 polymorphisms are relevant for the efficacy and adverse effects of numerous NSAIDs, sulfonylurea antidiabetic drugs and, most critically, oral anticoagulants belonging to the class of vitamin K epoxide reductase inhibitors. Warfarin has served as a practical example of how pharmacogenetics can be utilized to achieve maximum efficacy and minimum toxicity. For many of these drugs, a clear gene–dose and gene–effect relationship has been observed in patients. In this regard, CYP2C9 alleles can be considered as a useful biomarker in monitoring drug response and adverse effects. Genetic testing of CYP2C9 is expected to play a role in predicting drug clearance and conducting individualized pharmacotherapy. However, prospective clinical studies with large samples are warranted to establish gene–dose and gene–effect relationships for CYP2C9 and its substrate drugs. 相似文献
63.
目的 建立高效液相色谱-电感耦合等离子质谱(HPLC-ICP-MS)测定方法,分析金银花、泽泻、鸡血藤中4种不同价态砷,评估泽泻、金银花、鸡血藤中4种价态砷的残留情况,为制定相关残留限度提供依据。方法 采用0.05 mol·L-1 EDTA溶液超声提取样品中可溶性砷,采用HPLC-ICP-MS分析样品中可溶性砷的形态。结果 As(Ⅲ)、DMA、MMA、As(Ⅴ)在5~200 μg·L-1内线性良好,平均回收率(n=9)为105.1%~108.4%,方法检测限为0.01 mg·kg-1。泽泻检出少量As(Ⅲ)、As(Ⅴ),金银花检出少量As(Ⅲ)、DMA、As(Ⅴ),鸡血藤则均未检出As(Ⅲ)、DMA、MMA、As(Ⅴ)。结论 该方法操作简便、结果准确、重复性好,能满足4种不同价态砷的残留限度分析。 相似文献
64.
Claudia Fumarola Mara A. Bonelli Pier Giorgio Petronini Roberta R. Alfieri 《Biochemical pharmacology》2014
While PI3K/AKT/mTOR pathway is altered in a variety of cancers including non small cell lung cancer, abnormalities in this pathway are more common in squamous cell lung carcinoma than in adenocarcinoma of the lung. Moreover, aberrant activation of PI3K/AKT/mTOR pathway is one of the mechanisms of acquired resistance to EGFR-TK inhibitors in patients with adenocarcinoma carrying EGFR activating mutations. 相似文献
65.
目的:分析子野个数限值对宫颈癌固定野调强放疗(fixed-field intensity-modulated radiotherapy,ff-IMRT)计划的影响,寻求最优的子野个数限值。方法:选取10例接受ff-IMRT的宫颈癌患者,基于Monaco 5.11.03计划系统,以45 Gy/25 f处方剂量分别对同一患者设计8种ff-IMRT计划(ff-IMRT计划依据子野个数限值命名,子野个数限值分别为40、60、70、80、100、120、130、150),采用SPSS 20.0软件比较除plan100之外7个ff-IMRT计划与plan100剂量学参数、优化时间和治疗参数的差异。结果:8种ff-IMRT计划归一化后,plan40和plan60的D2%、Dmin、CI和HI均劣于plan100(P<0.05)。8种ff-IMRT计划均能较好保护危及器官(organ at risk,OAR)和正常组织。plan40小肠V45;plan40和plan60小肠D2cc,直肠、膀胱V45、D40%,两侧股骨头V40和正常组织 V35、V40均高于plan100(P<0.05)。plan40和plan60优化时间、治疗参数均优于plan100(P<0.05);plan120、plan130和plan150子野面积、子野个数(51~150 cm2和>150 cm2)和出束时间均劣于plan100(P<0.05)。结论:子野个数限值为70~100时,ff-IMRT计划能兼顾剂量学参数满足临床要求、优化时间和治疗参数最优化,建议在设计宫颈癌ff-IMRT计划时在该范围内设置子野个数限值。 相似文献
66.
67.
Cancer chemotherapy is characterized by significant interindividual variations in systemic clearance, therapeutic response, and toxicity. These variations are due mainly to genetic factors, leading to alterations in drug metabolism and/or target proteins. The aim of this study was to determine, using a human liver bank (N=14), the interindividual variations in the expression and activity of liver enzymes that metabolize the investigational anticancer drug 5,6-dimethylxanthenone-4-acetic acid (DMXAA), i.e cytochrome P450 (CYP1A2) and uridine diphosphate glucuronosyltransferase (UGT1A9/2B7). In addition, interindividual variations in enzyme inhibition, hydrolysis of DMXAA acyl glucuronide (DMXAA-G) by plasma and hepatic microsomes, and the binding of DMXAA by plasma proteins also were examined. The results indicated that there was approximately one order of magnitude of interindividual variation in the expression of CYP1A2 and UGT2B7, activity of the enzymes toward DMXAA, and inhibition potency (IC(50)) by diclofenac, cyproheptadine, and alpha-naphthoflavone. The enzyme activities toward DMXAA and IC(50) values were closely correlated with enzyme expression. There was a smaller (2- to 3-fold) variation in the enzyme-catalyzed hydrolysis of DMXAA acyl glucuronide in human plasma and liver microsomes (N=6) and in the binding of DMXAA by plasma proteins in humans. In conclusion, the interindividual variability of DMXAA disposition observed in vitro might reflect the greater elimination variability (>one order of magnitude) in Phase I cancer patients. The variability in DMXAA clearance in these cancer patients would be due mainly to differences in its metabolism and its metabolic inhibition by co-administered drugs. To a lesser extent, variability in the clearance of DMXAA could be due to the hydrolysis of its acyl glucuronide and/or its binding to plasma proteins. Further study is needed to examine the genotype-phenotype relationship, and the result, together with therapeutic drug monitoring may provide a useful strategy for optimizing DMXAA treatment. 相似文献
68.
69.
目的探讨藿胆丸的微生物限度检查方法的验证实验。方法按《中华人民共和国药典》2010年版一部微生物限度检查方法进行验证实验。结果藿胆丸对枯草芽孢杆菌、金黄色葡萄球菌具有很强的抑制作用,根据方法验证实验结果采用薄膜过滤法(200m/膜)进行本品的细菌计数,常规法进行霉菌及酵母菌计数,常规法进行控制菌检查。结论严格按照《中华人民共和国药典》要求,选择5株阳性菌株进行药品的微生物限度检查方法学验证实验极为必要。 相似文献
70.