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151.
152.
Intestinal metabolism of ethinyloestradiol and paracetamol in vitro: studies using Ussing chambers. 总被引:1,自引:1,他引:1 下载免费PDF全文
The intestinal mucosal metabolism of ethinyloestradiol (EE2) and paracetamol (P) has been studied in vitro in Ussing chambers. Histologically normal jejunum or ileum was obtained from 19 patients undergoing various resections. The muscularis externa was stripped off the mucosa and the mucosal sheets mounted between two perspex chambers. Tissue viability was routinely assessed by measurement of the transmural potential difference. The percentage of steroid in the serosal chamber, 2 h after addition of EE2 (2 microCi; 80 ng) to the mucosal chamber was 2.3 +/- 0.8% (mean +/- s.d.) which comprised unconjugated drug (0.4 +/- 0.3%), sulphate conjugates (0.7 +/- 0.5%) and glucuronides (0.9 +/- 0.8%). In the mucosal chamber, 56.6 +/- 11.4% was unconjugated steroid, 33.3 +/- 12.4% sulphate conjugates and 2.1 +/- 2.3% glucuronides. Small amounts of the oxidation products 2-hydroxy and 16-hydroxy-EE2 were present. At 2 h, the percentage of paracetamol in the serosal chamber was 3.2 +/- 1.4% (of added P; 2 microCi; 50 ng) of which 0.5 +/- 0.3% was paracetamol sulphate (PS) and 0.1% was paracetamol glucuronide (PG). In the mucosal chamber 2.4 +/- 0.8% and 1.0 +/- 0.2% was present as PS and PG respectively. The total amount of paracetamol conjugated was approximately 4.0%. When paracetamol in the mucosal chamber was increased to 50 micrograms (i.e. by a factor of 1000) there was a decrease in the percentage of added drug metabolized to PS and an increase in formation of PG. The glucuronide:sulphate ratio was increased from 0.34 to 3.56. Competition for sulphation was evident when both paracetamol and EE2 were presented to the intestinal mucosa.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
153.
目的 解陕西省死因监测病例来源分布,为提高死因监测数据的完整性和准确性提供依据。方法 从《中国疾病预防控制信息系统 - 死因报告信息系统》中导出的陕西省13个国家级死因监测点2015 - 2018年的网报数据进行分析。结果 2015 - 2018年陕西省13个国家级监测点共报告死亡病例129 740例,其中男性75 773例,女性53 688例。分别报告32 489例、33 212例、31 533例和32 227例死亡病例,各年性别比例均衡,趋势无统计学意义(趋势χ2 = 1.84,P = 0.17)。死亡病例主要来源于乡镇卫生院,占58.80%~61.51%,其次为社区卫生服务中心和县及县以上综合医院,二者分别报告占17.60%~19.81%和17.19%~18.69%(趋势χ2 = 27.79,P<0.01),在家中死亡的比例占绝大多数,73.06%~76.52%,死于医疗卫生机构的占17.67%~19.93%(趋势χ2 = 38.81,P<0.01)。死亡病例生前最高诊断单位以二级医院(占46.36%~49.93%)和三级医院(占41.75%~45.63%)为主(趋势χ2 = 48.80,P<0.01),最高诊断依据以临床+理化为主(占60.74%~63.57%)。结论 陕西省死因监测中发现虽然大多数病人在二级或三级医院就诊,且这一比例逐年提高,但绝大多数死亡病例死于家中,主要由乡镇卫生院专干完成死亡病例卡网报。因此,在今后工作中应加强对乡镇卫生院及社区卫生服务中心的培训,定期开展数据查漏补报和质量核查工作。 相似文献
154.
目的对用于评价西安城区居民膳食营养状况的西安食物频率问卷(FFQ)的重现性和准确性进行食物组的研究。方法在西安城区随机抽取出125名50~80岁当地居民,共完成6轮的食物摄入情况的调查,其中4轮24小时膳食回顾调查(24HDRs)的结果作为参考,通过第一轮FFQ结果与第二轮FFQ以及4轮24HDRs结果之间的比较分别进行FFQ的重现性和准确性研究。结果各个食物组在两轮FFQ间的Spearman相关系数在0.38(糕点类)~0.74(茶类)。第二轮FFQ与4轮24HDRs均值间的相关系数在0.12~0.74之间,经过个体内方差校正后,相关系数均有所提高。结论西安食物频率问卷可以相对准确、可靠地评价西安城区50岁以上居民的膳食营养状况。 相似文献
155.
Plasma concentrations of 3-keto-desogestrel after oral administration of desogestrel and intravenous administration of 3-keto-desogestrel 总被引:2,自引:0,他引:2
The plasma concentrations of 3-keto-desogestrel have been measured by radioimmunoassay in a crossover study in nine healthy feamle volunteers given oral desogestrel (150 μg) and ethinyloestradiol (30 μg) and intravenous (i.v.) 3-keto-desogestrel (150 μg) and ethinyloestradiol (30 μg).
Bioavailability ranged between 40.0 and 113% with a mean value (± SD) of 76.1 ± 22.5%. Only 3 subjects had a bioavailability of less than 70%. There was no significant difference in the elimination half life of 3-keto-desogestrel which was 12.6 ± 4.1h following i.v. administration and 11.9 ± 4.1h after oral administration of desogestrel. 相似文献
156.
目的:促进老年人新型冠状病毒肺炎中药防治的安全性及合理性。方法:根据全国各省制定的新型冠状病毒肺炎中医药预防方案,结合老年人的生理特质、病理情况、基础疾病及用药特点进行分析。结果:提出老年人新型冠状病毒肺炎中药防治的合理用药策略。结论:老年人作为预防新冠病毒感染的重点人群,应加强合理用药干预,确保中药用药安全有效。 相似文献
157.
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159.
Synthesized and directly acquired spin-echo images were compared in order to assess the validity of magnetic resonance (MR) image synthesis as a method enabling retrospective formation of images by interactive manipulation of scan parameters. Synthetic images subjectively compared favorably in both accuracy and precision with acquired images when formed for the same values of echo (TE) and repetition times (TR) and for interpolated and extrapolated values of both TE and TR. Plots of synthetic and acquired signals within the same pixel sectors quantitatively showed comparable values for several regions of interest in the brain. Percent error and noise-normalized differences between acquired and synthetic images were tested as a quantitative measure of accuracy. Percent error was consistently less than 5% for brain parenchyma, and synthetic signals were accurate to within four times the noise level at acquisition. The apparent signal-to-noise ratio of synthetic images was comparable, superior, or inferior to similar acquired images, depending on the values of TE and TR. Total acquisition time required for synthetic formation of images for arbitrary values of TE and TR was equivalent to that of a single direct acquisition with a TR of 2,500 msec. 相似文献
160.
The unbound percentage of saquinavir and indinavir remains constant throughout the dosing interval in HIV positive subjects 下载免费PDF全文
Boffito M Hoggard PG Reynolds HE Bonora S Meaden ER Sinicco A Di Perri G Back DJ 《British journal of clinical pharmacology》2002,54(3):262-268
AIMS: To measure the unbound plasma concentrations of saquinavir (SQV) and indinavir (IDV) and to relate them to the total plasma concentrations in order to establish the unbound percentage of protease inhibitors in vivo during a full dosage interval profile. METHODS: HIV-infected subjects (n = 35; median CD4 cell count = 340 x 10(6) cells l-1, range: 120-825; viral load < 50 copies ml-1 in 22/35) treated with SQV or IDV containing regimens were studied. Plasma drug samples were collected at 0, 2, 4, 8 and 12 h postdose for the twice daily regimens and 0, 1, 2, 4 and 8 h for the three times daily regimens. Ultra-filtration was used to separate unbound IDV and SQV in plasma and their respective concentrations were measured by a fully validated method using high performance liquid chromatography-mass spectometry (h.p.l.c.-MS/MS). RESULTS: Based on the ratio AUCunbound/AUCtotal, the median unbound percentage (95% CI for differences) of SQV and IDV from all the samples studied was 1.19% (0.99, 1.58%) and 36.3% (35.1, 44.2%), respectively. No significant difference was seen in the percentage binding of SQV between patients receiving SQV alone (median = 1.49%) or with ritonavir (median = 1.09%; P = 0.141; 95% CI for difference between medians = -0.145, 0.937) over the pharmacokinetic profile. Similarly, no significant difference was seen in the percentage binding of IDV in patients receiving IDV alone (median 35.2%) or with ritonavir (median = 41.3%; P = 0.069; 95% CI for difference between medians = -0.09, 15.4). The unbound concentrations of SQV (P < 0.0001; 95% CI for r(2) = 0.634, 0.815) and IDV (P < 0.0001; 95% CI for r(2) = 0.830, 0.925) remained constant as a proportion of total concentration over the full dosing profile. CONCLUSIONS: These in vivo data confirm previously published in vitro measurements of SQV and IDV protein binding. The unbound percentage of both protease inhibitors remained constant over the dosing interval. 相似文献