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1.
1. To investigate Genkwa Flos hepatotoxicity, a cell metabolomics strategy combined with serum pharmacology was performed on human HL-7702 liver cells in this study.

2. Firstly, cell viability and biochemical indicators were determined and the cell morphology was observed to confirm the cell injury and develop a cell hepatotoxicity model. Then, with the help of cell metabolomics based on UPLC-MS, the Genkwa Flos group samples were completely separated from the blank group samples in the score plots and seven upregulated as well as two down-regulated putative biomarkers in the loading plot were identified and confirmed. Besides, two signal molecules and four enzymes involved in biosynthesis pathway of lysophosphatidylcholine and the sphingosine kinase/sphingosine-1-phosphate pathway were determined to investigate the relationship between Genkwa Flos hepatotoxicity and these two classic pathways. Finally, the metabolic pathways related to specific biomarkers and two classic metabolic pathways were analyzed to explain the possible mechanism of Genkwa Flos hepatotoxicity.

3. Based on the results, lipid peroxidation and oxidative stress, phospholipase A2/lysophosphatidylcholine pathway, the disturbance of sphingosine-1-phosphate metabolic profile centered on sphingosine kinase/sphingosine-1-phosphate pathway and fatty acid metabolism might be critical participators in the progression of liver injury induced by Genkwa Flos.  相似文献   

2.
IntroductionEndoscopic surveillance guidelines for patients with repaired esophageal atresia (EA) rely primarily on expert opinion. Prior to embarking on a prospective EA surveillance registry, we sought to understand EA surveillance practices within the Eastern Pediatric Surgery Network (EPSN).MethodsAn anonymous, 23-question Qualtrics survey was emailed to 181 physicians (surgeons and gastroenterologists) at 19 member institutions. Likert scale questions gauged agreement with international EA surveillance guideline-derived statements. Multiple-choice questions assessed individual and institutional practices.ResultsThe response rate was 77%. Most respondents (80%) strongly agree or agree that EA surveillance endoscopy should follow a set schedule, while only 36% claimed to perform routine upper GI endoscopy regardless of symptoms. Many institutions (77%) have an aerodigestive clinic, even if some lack a multi-disciplinary EA team. Most physicians (72%) expressed strong interest in helping develop evidence-based guidelines.ConclusionsOur survey reveals physician agreement with current guidelines but weak adherence. Surveillance methods vary greatly, underscoring the lack of evidence-based data to guide EA care. Aerodigestive clinics may help implement surveillance schedules. Respondents support evidence-based protocols, which bodes well for care standardization. Results will inform the first multi-institutional EA databases in the United States (US), which will be essential for evidence-based care.Level of EvidenceThis is a prognosis study with level 4 evidence.  相似文献   
3.
Background The skin microdiallysis technique makes it possible to measure histamine release in intact human skin in vivo directly. In this study we have used the microdialysis technique to characterize histamine release by codeine after intracutaneous injectioin and following skin challenge by a novel atraumatic delivery technique. Objective The purpose of the study was to compare histamine release in human skin by codeine. delivered by an intraprobe drug delivery system (IPD) and intracutaneous injections (ICT), with respect to dose-response relations, kinetics of histamine appearance and decay, corelations between histamine release and skin respones, and reproducibility. Methods Hollow dialysis fibres were inserted intradermally in 12 healthy subjects. Twelve fibres were inserted in each subjects, six fibres in each arm. Each fibre was perfused at a rate of 3 μL/min, and samples were collected in 2 min fractions. By the IPD technique, codeine was administrered to the skin by adding codeine to the perfusion medium. Sequential IPD challenges were performed in one arm. and ICTs were done on the other arm. Results Sixfold serial dilutions of codeine (0.01-3 mg/mL) caused a significant doserelated histamine release by ICT and IPD. Peak histamine release was found within the first 4 min after skin challenge by ICT and IPD, followed by a fast decline with a dialysate histamine half life of approximately 2-3 min. Peak hisamine release was linearly correlates with cumulative release of the 20 min sampling period, and histamine release correlated with weal soze. The coefficient of variation on peak histamine releae was 18.9% and 4.8% for codeine ICT and IPD, respectively. Conclusioin We have described in detail codeine-induced histamine release in intact human skin in vivo by the microdialysis technique. It was possible to administer codeine atraumaticallyl to the skin by intraprobe delivery. The skin microdialysis codeine atraumaticallly to the skin by intraprobe delivery. The skin microdialysis technique opens up possibilities for measurement of infllammatory mediators release in normal and diseases skin, and it will be possible to deliver immunopharmacologically active drugsto the skin by intraprobe delivery.  相似文献   
4.
The known effects of drugs from a variety of pharmacologic/therapeutic classes on the respiratory system and worldwide regulatory requirements support the need for conducting respiratory evaluations in safety pharmacology. The objective of these studies is to evaluate the potential for drugs to cause secondary pharmacologic or toxicologic effects that influence respiratory function. Changes in respiratory function can result either from alterations in the pumping apparatus that controls the pattern of pulmonary ventilation or from changes in the mechanical properties of the lung that determine the transpulmonary pressures (work) required for lung inflation and deflation. Defects in the pumping apparatus are classified as hypo- or hyperventilation syndromes and are evaluated by examining ventilatory parameters in a conscious animal model. The ventilatory parameters include respiratory rate, tidal volume, minute volume, peak (or mean) inspiratory flow, peak (or mean) expiratory flow, and fractional inspiratory time. Defects in mechanical properties of the lung are classified as obstructive or restrictive disorders and can be evaluated in animal models by performing flow-volume and pressure-volume maneuvers, respectively. The parameters used to detect airway obstruction include peak expiratory flow, forced expiratory flow at 25 and 75% of forced vital capacity, and a timed forced expiratory volume, while the parameters used to detect lung restriction include total lung capacity, inspiratory capacity, functional residual capacity, and compliance. Measurement of dynamic lung resistance and compliance, obtained continuously during tidal breathing, is an alternative method for evaluating obstructive and restrictive disorders, respectively, and is used when the response to drug treatment is expected to be immediate (within minutes post-dose). The species used in the safety pharmacology studies conducted in our laboratory are the same as those used in toxicology studies since pharmacokinetic and toxicologic/pathologic data are available in these species. These data can be used to help select test measurement intervals and doses and to aid in the interpretation of functional change. The techniques and procedures for measuring respiratory function parameters are well established in guinea pigs, rats, and dogs.  相似文献   
5.
Omeprazole is a substituted benzimidazole that causes dose-dependent intracellular inhibition of gastric acid secretion in humans. This double-blind study examined the effect of omeprazole in decreasing gastric acidity and gastric residual volume in outpatient adults. Unpremedicated outpatients, ASA I-III, 18 years or older (n = 17), were randomly assigned to receive omeprazole 80 mg, or placebo by mouth the night before scheduled elective outpatient surgery. The patients were fasted for 8 h prior to surgery. After the patient was anesthetized, an orogastric tube was inserted with proper placement verified by auscultation for gastric sounds. Gastric residual contents were withdrawn into a Luken's trap, and pH was then determined and gastric volume indexed to weight (ml.kg-1). Data were analyzed by a t-test, with P less than 0.05 considered statistically significant. Patient characteristics of both groups were similar. There was a statistically significant difference between the two groups for pH (P = 0.02), but not between the two groups for gastric volume indexed to weight (P = 0.07).  相似文献   
6.
系统采用基于TCP/IP协议的国际互联网为基础,采用B/S结构,客户端采用IE浏览器,服务器端采用WINDOW2000的IIS作为服务器。其主要功能:工作督办、工作信息、电子邮件、收文、发文、图书管理、档案管理、车辆管理、日程管理、待办事宜、电子论坛、考勤管理等。  相似文献   
7.
兔眼滤过术中应用抗瘢痕药物后的眼压变化   总被引:2,自引:2,他引:0  
目的:在兔眼滤过术中应用两种抗瘢痕药物后观察其眼压变化,探讨提高青光眼手术成功率的抗瘢痕药物种类及用药方式。方法:将激素及丝裂霉素分别应用于兔眼滤过术中,测定术前、术后3d、7d和1个月眼压并进行分析。结果:①术前各组间眼压元显著差异;②术后 3 d和 7 d,甲强龙各浓度组眼压与术前相比有显著性差异(P<0.01),而组间两两比较差异不显著(P>0.05);③术后1个月实2、3、4组和对2组眼压均较术前明显下降,差异有显著性(P<0.01),各组间差异不显著(P>0.05);④术后1个月实1组和对1组眼压恢复至术前水平,差异不显著(P>0.05),其两组间差异不显著(P>0.05)。结论:眼压变化的结果表明甲强龙不仅具有早期抑制肉芽组织的作用,而且在一定浓度下对肉芽组织的成熟也有抑制作用,提示甲强龙术中湿片贴敷是一种安全、有效的抗瘢痕方法。  相似文献   
8.
本实验就复方硅橡胶栓堵剂(CSR)对家兔输卵管上皮细胞趋微结构的影响进行了观察分析,并测定了上皮细胞内铜元素的含量变化,电镜观察表明:家充输卵管经复方硅橡胶栓堵后,其上皮细胞表面结构、细胞连接、细胞核等超微结构均未发生明显的形态改变:注药侧(右侧〕和对照侧(左侧)输卵管上皮细胞内虽有少数线粒体膨胀,但两组间无论在线粒体数目,膨胀线粒体百分率以及线粒体外膜比表面等方面均无差异(P>0.1),电镜X—时线能谱分析表明:注药侧输卵管上皮细胞内铜元素的相对含量咯高于对照组,而且铜元素多畜集于线粒体内。  相似文献   
9.
目的测量2450MHz频率下蒸馏水和不同浓度NaCl溶液的复介电常数,用以判定系统的可靠性和稳定性.方法根据微扰法得到复介电常数的测量公式,然后通过实验对已知参数的蒸馏水和NaCl溶液进行测量,并计算其复介电常数和电导率,验证计算结果的可靠性和稳定性.结果对计算结果进行统计分析和误差分析,其均值、标准差和变异系数表明,最终结果可与M.I.T标准较好地吻合.结论这种系统可较好地测量2450MHz频率下高损耗介质的复介电常数,测量系统的主要误差是由介质体积的误差引起的,因此精确测量介质体积是测量生物组织等高损耗介质复介电常数的关键.  相似文献   
10.
小鼠单次经口灌服司帕沙星4、20和100mg/kg后,动物的活动正常,未出现兴奋的抑制作用;小鼠单次经口灌服司帕沙星4、20和100mg/kg,与戊巴比妥钠镇静催眠无明显协同作用;给猫静脉注射司帕沙星4、16和64mg/kg,对动物呼吸和心血管系统无明显影响。  相似文献   
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