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51.
52.
9-(2-膦酰甲氧乙基)腺嘌呤及其位置异构体3-(2-膦酰甲氧乙基)腺嘌呤的合成和抗病毒活性研究 总被引:1,自引:0,他引:1
Phosphonylmethoxyethyl)adenine (1),PMEA,an acyclic nucleotide withbroad-spectrum antiviral activity was synthesized with some modifications of Holy's procedure.Simutaneously,an N-3 regioisomer(2)of PMEA and a by-preduct, formaldehyde di-[2-(9-adenyl)ethyl] acetal(7)were seperated by silica gel chromatography in the ratio of 50:10:1.Compound(2)and(7) are new compounds that we have not yet found in literatures. The structure of them weredetermined with 1HNMR,2DNMR, MS and Spot test.Antiviral test showed that N-3 isomer(2)completely lost activity against both HIV-1 and HSV-1 in vitro. It seems that regiospecificity of theacyclic nucleotide structure is important for antiviral activity. 相似文献
53.
Hoos A. D'Incan C. Gissmann L. Altmann A. Momburg F. Nindl I. Osen W. Schönning BH. Jochmus I. 《Archives of virology》1996,141(3-4):449-458
Archives of Virology - The low expression of major histocompatibility complex (MHC) class I antigens on human papillomavirus (HPV)-infected cervical carcinoma cells may be responsible for an... 相似文献
54.
Benedikte Thuesen Ove B. Schaffalitzky de Muckadell Jens J. Hoist Mogens Bahnsen 《The American journal of gastroenterology》1987,82(8):723-726
The concentrations of secretin and somatostatin in plasma were measured in 10 healthy subjects during a 4-day fast. The fast induced increased concentrations of plasma secretin (from 1.2 +/- 0.5 to 9.5 +/- 2.3 pmol/l) and somatostatin (from 5.2 +/- 1.5 to 8.6 +/- 1.7 pmol/l). Gastric aspiration for 1 h suppressed the high concentrations of secretin by 46% and somatostatin by 27%. The intravenous infusion of glucose reduced the plasma secretin even further by 88%; the decrease in somatostatin was not statistically significant. The study shows that gastric aspiration and/or glucose infusion suppressed the high plasma concentration of secretin and that factors other than hyperchlorhydria must be involved in the hypersecretinemia seen during starvation. The elevated plasma somatostatin concentration seen during starvation may be a consequence of increased acid secretion. 相似文献
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Quantitative liver function in patients with rheumatoid arthritis treated with low-dose methotrexate: a longitudinal study 总被引:4,自引:0,他引:4
Beyeler C; Reichen J; Thomann SR; Lauterburg BH; Gerber NJ 《Rheumatology (Oxford, England)》1997,36(3):338-344
The objectives were to determine quantitative liver function prospectively
in patients with rheumatoid arthritis (RA) treated with low-dose
methotrexate (MTX), to search for risk factors for a loss of quantitative
liver function and to assess the relationship between quantitative liver
function and histological staging. A total of 117 patients with RA (ACR
criteria, 85 women, mean age 59 yr) had measurements of galactose
elimination capacity (GEC), aminopyrine breath test (ABT) and liver enzymes
[aspartate amino transferase (AST), alanine amino transferase (ALT),
alkaline phosphatase (AP), 7-glutamyl transferase (GGT), bile acids,
bilirubin, albumin] before treatment with weekly i.m. MTX injections and
every year thereafter. In 16 patients, liver biopsies were performed.
Before the introduction of MTX, mean GEC was 6.6 mg/min/kg [5th to 95th
percentile (5-95 PC) 5.1- 8.5; reference range 6.0-9.1] and mean ABT was
0.80% kg/mmol (5-95 PC 0.42-1.30: reference range 0.6-1.0). During
treatment with MTX [mean weekly dose 11.8 mg (5-95 PC 5.4-20.2), mean
observation period 3.8 yr (5-95 PC 0.4-6.9)], significant declines of GEC
(-0.12 mg/min/kg per year. t = 3.30, P < 0.002) and ABT (-0.06% kg/mmol
per year, t = 4.81, P < 0.001) were observed. Negative correlations were
found between the annual change in GEC and GEC at baseline (Rs = -0.40, P
< 0.0001), and the annual change in ABT and ABT at baseline (Rs = -0.43,
P < 0.0001). No correlations were found between the annual change in GEC
or ABT and weekly MTX dose, age or percentage of increased liver enzymes,
and no effect of a history of alcohol consumption > 30 g/week became
evident. Two patients with Roenigk grade III had impaired quantitative
liver function, while 14 patients with Roenigk grades I and II exhibited a
high variability of GEC and ABT from normal to abnormal values. The
continuous declines in GEC and ABT observed deserve attention in patients
with prolonged treatment. Patients with a low GEC or ABT at baseline seem
not to be at increased risk for a further loss of quantitative liver
function. An impaired GEC or ABT does not necessarily concur with hepatic
fibrosis on histological examination.
相似文献
57.
58.
Work in progress: [18F] fluorodeoxyglucose and positron emission tomography in the evaluation of radiation necrosis of the brain 总被引:3,自引:0,他引:3
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