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51.
52.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
53.
B N Gray C Walker L Andrewartha S Freeman R C Bennett 《The Australian and New Zealand journal of surgery》1988,58(1):43-46
A controlled randomized clinical trial was undertaken to assess the ability of combined non-specific and specific immunotherapy to alter the disease-free interval and overall survival of patients with Stage B or C large bowel cancer. The immunotherapy consisted of a 2 year programme of vaccinations with BCG and neuraminidase-treated autologous tumour cells. Three hundred and one patients entered the trial. At 5 years of follow-up there is no evidence that this form of immunotherapy can alter either the disease-free interval or survival in this group of patients. 相似文献
54.
Irregularly shaped small shadows on chest radiographs, dust exposure, and lung function in coalworkers' pneumoconiosis.
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H P Collins J A Dick J G Bennett P O Pern M A Rickards D J Thomas J S Washington M Jacobsen 《Occupational and environmental medicine》1988,45(1):43-55
The predominant shapes of small opacities on the chest radiographs of 895 British coalminers have been studied. The aims were to determine whether irregular (as distinct from rounded) small opacities can be identified reproducibly, whether their occurrence is related to dust exposure, and whether they are associated with excess prevalence of respiratory symptoms or impairments of lung function. Six of the doctors responsible for regular radiological surveys of all British coalminers each classified all 895 radiographs twice and independently, using the International Labour Organisation's 1980 classification system. The majority view was that 39 films showed predominantly irregular small opacities, 131 showed predominantly small rounded opacities, and 587 showed no small opacities. Readers' opinions varied about the presence and shapes of shadows on the other 138 films. In general, consistency between readers (and within readers on repeated viewings) was satisfactory. The occurrence and profusion of irregular shadows were related significantly both to the men's ages and additionally to their cumulative exposure to respirable coalmine dust as determined from 15 years' dust monitoring close to where the miners had worked. For any given level of exposure, the average level of profusion of the small irregular opacities was less than the corresponding profusion of small rounded opacities. The prevalence rates of chronic cough and phlegm, and of breathlessness, were higher in those with small irregular opacities than in those with no small opacities (category 0/0), but the differences were not statistically significant after adjustment for other factors including smoking habits. The presence of irregular (but not rounded) small shadows was associated with an impairment in respiratory function averaging about 190 ml deficits in both FEV1 and FVC. These deficits were not explicable in terms of the men's ages, body sizes, and smoking habits and they were in addition to the lung function losses attributable to the miners' dust exposure as such. It is concluded that the presence and profusion of small irregular opacities should be taken into consideration when assessing the severity of coalworkers' simple pneumoconiosis. 相似文献
55.
J G Bennett 《British medical journal (Clinical research ed.)》1988,296(6638):1687-1688
56.
57.
R A Price K Lunetta R Ness M A Charles M F Saad E Ravussin P H Bennett D J Pettitt W C Knowler 《International journal of obesity (2005)》1992,16(11):851-857
We examined distribution characteristics of the body mass index (BMI; weight/height; kg/m2) in a sample of 1128 male and 1372 female Pima Indians aged 15-65 years. We found that women had a higher mean and variance of BMI than men. From commingling analyses, we determined that the distribution of BMI could be accounted for either by a single skewed distribution or by a mixture of multiple normal components. These component distributions may be used to define provisional thresholds in selecting families for genetic studies. To ensure genetic segregation of obesity predisposing genes in Pima families will require that some members have BMIs > or = 40 kg/m2. 相似文献
58.
Cationic lipids enhance cellular uptake and activity of phosphorothioate antisense oligonucleotides. 总被引:37,自引:0,他引:37
C F Bennett M Y Chiang H Chan J E Shoemaker C K Mirabelli 《Molecular pharmacology》1992,41(6):1023-1033
We have investigated the use of a cationic lipid preparation to enhance antisense oligonucleotide activity in human umbilical vein endothelial cells. A liposomal preparation containing the cationic lipid N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA) was found to increase by at least 1000-fold the potency of an antisense oligonucleotide (ISIS 1570) that hybridizes to the AUG translation initiation codon of human intercellular adhesion molecule-1. In the presence of 8 microM DOTMA, 6-15-fold more 35S-ISIS 1570 associated with cells, at oligonucleotide concentrations from 0.01 to 5 microM, than did in the absence of DOTMA. Both 35S-ISIS 1570 association with cells and antisense activity were increased as a function of DOTMA concentration and with increasing time of incubation with the cationic lipid. Fluorescein-labeled ISIS 1570 was used to assess the intracellular distribution of the oligonucleotide in the presence and absence of DOTMA. In the absence of DOTMA, the oligonucleotide localized to discrete structures in the cytoplasm of the cell, resulting in a punctate fluorescence pattern. In the presence of DOTMA, cellular fluorescence markedly increased and the oligonucleotide localized within the nucleus, as well as to discrete structures in the cytoplasm. Accumulation of the oligonucleotide in the nucleus in the presence of DOTMA was time and temperature dependent. Nuclear accumulation was inhibited by preincubation of the cells with monensin but not chloroquine, NH4Cl, nocodazole, colcemid, or brefeldin A. These data demonstrate that cationic lipids increase antisense activity by increasing the amount of oligonucleotide associated with cells and altering intracellular distribution of the oligonucleotide. 相似文献
59.
J M Bennett P C Spyrou S Konstantinides 《Suid-Afrikaanse tydskrif vir geneeskunde》1988,73(7):434-435
A case of spontaneous multivessel coronary artery spasm documented by coronary arteriography is reported. The patient was also resistant to sublingual nitrates and nifedipine and required intracoronary nitroglycerine to alleviate the spasm. 相似文献
60.