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1.
青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究 总被引:1,自引:0,他引:1
将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5~4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。 相似文献
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Cloning and expression of the phospholipase C gene from Clostridium perfringens and Clostridium bifermentans. 总被引:11,自引:11,他引:11 下载免费PDF全文
The phospholipase C gene from Clostridium perfringens was isolated, and its sequence was determined. It was found that the structural gene codes for a protein of 399 amino acid residues. The NH2-terminal residues have the typical features of a signal peptide and are probably cleaved after secretion. Escherichia coli cells harboring the phospholipase C gene-containing plasmid expressed high levels of this protein in the periplasmic space. Phospholipase C purified from E. coli transformants was enzymatically active, hemolytic to erythrocytes, and toxic to animals when injected intravenously. The phospholipase C gene from a related organism, Clostridium bifermentans, was also isolated. The two phospholipase C genes were found to be 64% homologous in coding sequence. The C. bifermentans protein, however, was 50-fold less active enzymatically than the C. perfringens enzyme. 相似文献
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Ka Hing Wong Kenny Chi-Wai Chan Shui Shan Lee Sik To Lai Nelson Lee Clive Cockram Wai Sang Poon Tak Yin Tsang Yuk Keung Tso Ka Fai To 《Journal of microbiology, immunology, and infection》2007,40(2):173-177
Epstein-Barr virus (EBV)-associated smooth muscle tumor (SMT) is a recognized but uncommon disease that is found to occur in patients with immunocompromised conditions such as acquired immunodeficiency syndrome (AIDS). These tumors may be multifocal and located at unusual sites, such as the brain and liver. This report describes the case of 2 AIDS patients with EBV-associated SMT and highlights the features and outcome of this rare but potentially important tumor in human immunodeficiency virus management. 相似文献
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Kenneth Siu-Sing Leung Timothy Ting-Leung Ng Alan Ka-Lun Wu Miranda Chong-Yee Yau Hiu-Yin Lao Ming-Pan Choi Kingsley King-Gee Tam Lam-Kwong Lee Barry Kin-Chung Wong Alex Yat Man Ho Kam-Tong Yip Kwok-Cheung Lung Raymond Wai-To Liu Eugene Yuk-Keung Tso Wai-Shing Leung Man-Chun Chan Yuk-Yung Ng Kit-Man Sin Kitty Sau-Chun Fung Sandy Ka-Yee Chau Wing-Kin To Tak-Lun Que David Ho-Keung Shum Shea Ping Yip Wing Cheong Yam Gilman Kit-Hang Siu 《Emerging infectious diseases》2021,27(1):196
Initial cases of coronavirus disease in Hong Kong were imported from mainland China. A dramatic increase in case numbers was seen in February 2020. Most case-patients had no recent travel history, suggesting the presence of transmission chains in the local community. We collected demographic, clinical, and epidemiologic data from 50 patients, who accounted for 53.8% of total reported case-patients as of February 28, 2020. We performed whole-genome sequencing to determine phylogenetic relationship and transmission dynamics of severe acute respiratory syndrome coronavirus 2 infections. By using phylogenetic analysis, we attributed the community outbreak to 2 lineages; 1 harbored a common mutation, Orf3a-G251V, and accounted for 88.0% of the cases in our study. The estimated time to the most recent common ancestor of local coronavirus disease outbreak was December 24, 2019, with an evolutionary rate of 3.04 × 10−3 substitutions/site/year. The reproduction number was 1.84, indicating ongoing community spread. 相似文献
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In densely populated cities such as Hong Kong where people live and work in high-rise buildings that are all built with concrete, the indoor gamma dose rate and indoor radon concentration are not wide ranging. Indoor gamma dose rates (including cosmic rays) follow a normal distribution with an arithmetic mean of 0.22 +/- 0.04 microGy h(-1), whereas indoor radon concentrations follow a log-normal distribution with geometric means of 48 +/- 2 Bq m(-3) and 90 +/- 2 Bq m(-3) for the two main categories of buildings: residential and non-residential. Since different occupations result in different occupancy in different categories of buildings, the annual total dose [indoor and outdoor radon effective dose + indoor and outdoor gamma absorbed dose (including cosmic ray)] to the population in Hong Kong was estimated based on the number of people for each occupation; the occupancy of each occupation; indoor radon concentration distribution and indoor gamma dose rate distribution for each category of buildings; outdoor radon concentration and gamma dose rate; and indoor and outdoor cosmic ray dose rates. The result shows that the annual doses for every occupation follow a log-normal distribution. This is expected since the total dose is dominated by radon effective dose, which has a log-normal distribution. The annual dose to the population of Hong Kong is characterized by a log-normal distribution with a geometric mean of 2.4 mSv and a geometric standard deviation of 1.3 mSv. 相似文献
7.
C W Jones J G Cunha-Vaz R C Zeimer M M Rusin P W Langenberg C M Vygantas M O Tso O Jonasson 《Experimental eye research》1986,42(5):467-477
Normal- and diabetic rhesus monkeys without retinopathy demonstrable by ophthalmoscopy or fluorescein angiography were examined with ocular fluorophotometry to detect alterations in their blood-ocular barriers. All vitreous fluorophotometry values were corrected for fluorescence attributable to background levels and then normalized to a blood fluorescein level of 10 micrograms ml-1. Reproducibility studies demonstrated an average coefficient of variation of 0.17 for all animals combined. Insulin-dependent monkeys, both pancreatectomized and streptozotocin-treated, demonstrated significantly higher posterior vitreous fluorescence levels than either control animals or monkeys treated with streptozotocin that were not insulin-dependent. These results cannot be attributed to differences in fluorescein binding or to vitreous abnormalities. However, 14 out of 24 (58%) of the insulin-dependent animals exhibited posterior vitreous fluorescence values within two standard deviations of the control mean. No correlation was apparent between the vitreous values and age or duration of treatment. No difference in anterior chamber concentrations was found between groups after correction. Our results indicate that alterations in blood-retinal barrier can occur in insulin-dependent diabetic monkeys before development of retinopathy. 相似文献
8.
Balwinder Singh Anastasia K. Yocum Rebecca Strawbridge Katherine E. Burdick Caitlin E. Millett Amy T. Peters Sarah H. Sperry Giovanna Fico Eduard Vieta Norma Verdolini Ophelia Godin Marion Leboyer Bruno Etain Ivy F. Tso Brandon J. Coombes Melvin G. McInnis Andrew A. Nierenberg Allan H. Young Melanie M. Ashton Michael Berk Lana J. Williams Kamyar Keramatian Lakshmi N. Yatham Bronwyn J. Overs Janice M. Fullerton Gloria Roberts Philip B. Mitchell Ole A. Andreassen Ana C. Andreazza Peter P. Zandi Daniel Pham Joanna M. Biernacka Mark A. Frye The FACE-BD Collaborators The Global Bipolar Cohort Collaborative 《Bipolar disorders》2024,26(1):22-32
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The aim of our study was to determine the possible pathophysiological mechanisms of hypophosphataemia in a group of 127 patients admitted to hospital for alcohol-related causes. Blood and fresh urine specimens were taken to determine acid-base and electrolyte parameters. Thirty-seven patients (29.1%) had hypophosphataemia (serum phosphorus <0.77 mmol/l) with a range of serum phosphorus of 0.32-0.74 mmol/l. In 17 hypophosphataemic patients inappropriate phosphaturia (FEP04 >20%, TmPO4/GFR<0.80 mmol/l) was evident, possibly due to hypomagnesaemia, metabolic acidosis, metabolic alkalosis, or a proximal tubular defect in phosphate transport. The causes of hypophosphataemia in the remaining 20 patients were alcohol withdrawal syndrome, respiratory alkalosis and diarrhoea. Patients with hypophosphataemia were more often found to have hypomagnesaemia and respiratory alkalosis than normophosphataemic patients. In conclusion, hypophosphataemia is frequently observed in alcoholic patients due to various pathophysiological mechanisms, such as inappropriate phosphaturia, increased phosphorus entry into cells and increased gastrointestinal loss of phosphate. 相似文献