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81.
Phytate was digested by wheat bran phytase to yield inositol tetrakisphosphate. Periodate-oxidized inositol tetrakisphosphate (oxyIP4) was coupled by means of reductive alkylation to hemoglobin and the covalent dextran-hemoglobin conjugate to yield the rightshifted (rs) compounds rsHb and rsDxHb, respectively. The variations of the oxygen dissociation curves of these molecules with pH and temperature were compared to those of hemoglobin. The variations with pH were found to be less pronounced for these rightshifted forms. An extensive decrease in the half-saturation oxygen tension was observed, however, with both rsHb and rsDxHb, as in the case of unmodified Hb. Modification of hemoglobin by oxyIP4 at the polyphosphate site was suggested by the lack of a further rightshifting effect of phytate on rsHb, and by the similarity between the difference spectrum of rs-methemoglobin and the difference spectrum induced by the addition of phytate. 相似文献
82.
Summary Chronic treatment with conventional lithium carbonate was interrupted in a selected group of 40 psychiatric patients of mixed sex and race. All patients had normal renal function. Serum samples were taken 12, 24, 36 and 48 h after the last dose and lithium was assayed by atomic absorption spectrophotometry. Decay rates calculated for the 12–24 h and 36–48 h periods yielded different values. This was ascribed to the presence of an incomplete redistribution phase during the earlier period. The distribution of elimination rates determined during the later period gave a more symmetrical spread and approximated a normal distribution. The mode, median, mean and standard deviation of the lithium elimination half-lives were 12.5, 14, 18.2 and 7.3 h and 22.5, 24.5, 29.8 and 10.1 h for the two periods, respectively. The results contrast sharply with another report of the distribution spread of elimination half-lives in a much larger sample. The current values have implications for dosage prediction, serum level monitoring and dosage formulation, especially sustained-release preparations. The evidence was against the possibility that some individuals retain lithium. 相似文献
83.
84.
褶合曲线分析法同时测定小儿复方苯巴比妥片中四组分的含量 总被引:2,自引:0,他引:2
目的:不经分离同时测定小儿复方苯巴比妥片中四组分的含量。方法:以褶合光谱为基础,结合当前最优秀的数值计算法——偏最小二乘法(PLS法)利用计算机信息处理技术的褶合曲线分析法。结果:小儿复方苯巴比妥片中阿司匹林、非那西丁、咖啡因和苯巴比妥四组分的平均回收率及相对标准偏差(RSD)分别为99.75,0.92%;100.47,0.56%;99.82,1.12%;100.08,0.86%。结论:该方法可以用于小儿复方苯巴比妥片剂的质量监控。 相似文献
85.
目的探讨老年非小细胞肺癌患者联合化疗时卡铂按AUC=5mg/ml·min(AUC,areaundertheconcentrationtimecurve)的剂量是否适宜。方法33例老年晚期非小细胞肺癌患者采用Taxol+CBP、Gemzar+CBP、NVB+CBP方案化疗,卡铂用药剂量按AUC=5的水平给药。全部患者共完成73周期化疗。每周期化疗前后对患者的化疗毒副反应及生活质量变化进行评估。结果骨髓毒副反应常见且较重,中性粒细胞出现Ⅲ/Ⅳ级副反应为47.9%(35/73)、血小板出现Ⅲ/Ⅳ级副反应为28.8%(21/73)。其余毒副反应不重。生存质量评分(依据国内肿瘤患者生存质量评分标准)平均下降6.5分。结论老年非小细胞肺癌患者联合化疗时,卡铂按AUC=5的剂量水平用药毒副反应较重,且对生存质量有不利影响,可能与剂量偏大有关。 相似文献
86.
基于Hilbert曲线的数字图像置乱方法研究 总被引:27,自引:0,他引:27
研究了基于Hilbert曲线的数字图像置乱方法 ,引入二个概念 :“重合度”和“Hilbert曲线的平移” ,利用Hilbert曲线平移 ,获得了更多新的置乱路径 ,并根据重合度变化图探讨了置乱变换的规律 ,以测试置乱变换的周期和拟周期。然后把基于Hilbert曲线的置乱方法推广到任意大小的图像。实验结果表明 :利用Hilbert路径进行置乱不仅具有非常大的置乱路径选择空间 ,而且具有很好的置乱效果和极大的置乱周期 ,具有较大的实用性。 相似文献
87.
正常眼压性青光眼确诊时各指标间病变程度的关系 总被引:4,自引:0,他引:4
目的 考察正常眼压性青光眼 (normalpressureglaucoma ,NPG)患者确诊时的临床表现 ,探讨各指标间病变程度的关系。方法 10 5例NPG患者 ,分析眼压曲线的平均状态、波动幅度和双眼对称性 ,观察视野和眼底C/D垂直径比值、盘沿缩窄和视网膜神经纤维层 (RNFL)改变。结果 眼压曲线双眼对称 ,总体波动水平位于 16mmHg上下 ,最高值在 10AM ,最低值在 10PM ,但10PM最低值高于年龄可比的正常人群的平均眼压 (P <0 0 1)。单值眼压分布位于 10~ 2 1mmHg ,峰值与谷值相差约 4mmHg。视野在 5 5例患者为单眼损害 ,在 14 9眼的视野损害中 ,绝大多数损害形态和部位与眼压升高的原发性开角型青光眼 (hp -POAG)相符合 ,但旁中心损害侵入中心固视区者约占 2 2 % ,而在轻度损害中约占 1/3。眼底C/D值右眼为 0 77± 0 15 ,左眼为 0 71± 0 16,二者均大于一般群体上限和早期hp -POAG患者的C/D值 (P <0 0 1) ,但在不同程度损害的视野中差异不显著 (P >0 10 ) ,盘沿缩窄和RNFL缺损的发生率分别为 5 0 %以上和 60 %以上 ,二者差异不显著 (P>0 0 5 )。结论 NPG患者的眼压在绝对值、波动幅度和双眼对称性上均与正常眼压各指标相一致 ,对诊断无定性价值。确诊时眼底C/D值大于早期hp -POAG的C/D值 ,盘沿缩窄和RNFL缺损的 相似文献
88.
Brawer MK Cheli CD Neaman IE Goldblatt J Smith C Schwartz MK Bruzek DJ Morris DL Sokoll LJ Chan DW Yeung KK Partin AW Allard WJ 《The Journal of urology》2000,163(5):1476-1480
PURPOSE: Determining serum total prostate specific antigen (PSA) has proved to be a valuable diagnostic aid for detecting prostatic carcinoma, although the lack of specificity has limited its usefulness. Studies indicate that the use of percent free PSA would improve specificity while maintaining sensitivity. Since complexed PSA represents the major proportion of measurable PSA in serum, we determined whether it represents a single test alternative to the use of percent free PSA for the early detection of prostate cancer. MATERIALS AND METHODS: Archival serum was obtained from 385 men with no evidence of malignancy on biopsy and 272 with biopsy confirmed prostate cancer. We determined the concentration and proportion of total, complexed and free PSA. RESULTS: Receiver operating characteristics analysis using total PSA results from all samples (range 0.32 to 117 ng./ml.) indicated that the areas under the curve for complexed PSA alone as well as the free-to-total and complexed-to-total PSA ratios were similar and significantly greater than those for total PSA alone. Within the range of 85% to 95% sensitivity receiver operating characteristics analysis revealed that the specificity of complexed PSA was higher than that of total PSA and equivalent to that of the free-to-total PSA ratio. We noted a similar improvement in specificity in the 4 to 10 ng./ml. total PSA range. Using published cutoff values for complexed, total and percent free PSA when total PSA was in the 4 to 10 ng./ml. range the sensitivity and specificity of complexed and percent free PSA were similar. Within the 4 to 10 ng./ml. total PSA range the population of patients with no evidence of malignancy and complexed PSA below the upper limit was different with respect to total PSA from that with no evidence of malignancy and free PSA greater than 25%. CONCLUSIONS: The measurement of complexed PSA represents an alternative to the use of percent free PSA, although the patient populations identified by the 2 tests are different. 相似文献
89.
Is normal β-hCG regression curve helpful in the diagnosis of persistent trophoblastic disease? 总被引:1,自引:0,他引:1
N. Behtash F. Ghaemmaghami H. Honar K. Riazi A. Nori M. Modares & A. Mousavi 《International journal of gynecological cancer》2004,14(5):980-983
OBJECTIVE: The aim of this study was to evaluate the probable usefulness of normal beta-human chorionic gonadotropin (beta-hCG) regression curve in the diagnosis of persistent trophoblastic disease (PTD). METHODS: A log-value regression curve was developed from the means and 95% confidence limits of serial weekly serum beta-hCG titers of 43 patients with uneventful complete hydatidiform moles and 14 patients, who were previously confirmed as PTD. RESULTS: All 14 PTD patients (100%) had abnormal values, beyond normal range, within 4 weeks. beta-hCG was in its upper values, compared to normal regression curve at 2.29 +/- 0.19 weeks. This was earlier than plateau or rise detection at 4.21 +/- 0.33 weeks (P < 0.001). Within 3 weeks of evacuation, 13 of 14 (92.86%) PTD patients' beta-hCG values exceeded the normal range, whereas only six of 14 (42%) showed a rise or plateau. CONCLUSION: Our finding indicates that the normal beta-hCG regression curve may be useful for quicker detection of PTD than the plateau or rise of level. 相似文献
90.