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21.
22.
一种新的正交参数选优法及其在非线性回归分析中的应用 总被引:2,自引:0,他引:2
非线性回归分析是工程中经常采用的一种用来估计数学模型参数的方法,该方法能否顺利运用与参数初始值的选择有极大关系。本研究提出一种新的正交参数选优法——阻尼正交表法,它不仅可以保证非线性回归分析算法的顺利收敛,而且能够显著提高后者的收敛速度,进而极大改善非线性回归分析算法的应用性能。本研究的数值试验及心肌造影超声心动图定量分析应用实例表明,作为对传统正交参数选优法的一种改进,阻尼正交表法在科学与工程计算或信号与信息处理领域有着很好的应用前景。 相似文献
23.
Objective: 5-Aminoisoquinolinone, a water-soluble, potent inhibitor of the activity of poly (adenosine 5'-diphosphate ribose) polymerase, plays an important role in the tissue injury associated with ischaemia-reperfusion injury and inflammation by inhibiting the activity of poly (adenosine 5'-diphosphate ribose) polymerase and the expression of cell adhesion molecules such as ICAM-1, P-selectin et al. But how about it in the tumor is not clear. The aim of the present study was to study the effects of 5-Aminoisoquinolinon on the adhesion of colon carcinoma line HT-29 cells to human umbilical vein endothelial cells; and the effects of 5-Aminoisoquinolinon on the expression of ICAM-1, P-selectin and the activity of poly (adenosine 5'-diphosphate ribose) polymerase in colon carcinoma HT-29 cells. Methods: The adhesion of HT-29 cells to human umbilical vein endothelial cells was detected by adhesive experiment. Immunocytochemically Streptavidin-Peroxidase method was used to investigate the expression of ICAM-1, P-selectin and Poly (adenosine 5'-diphosphate ribose)( the product of poly (adenosine 5'-diphosphate ribose) polymerase activation). Results: the results of the adhesion assay of HT-29 cells to HUVEC showed that the OD570 value in each 5-AIQ-treated group was significant lower than that in the control group (5-AIQ-untreated) in a dose-dependent manner. The expression of ICAM-1, P-selectin and Poly (adenosine 5'-diphosphate ribose) was significant lower in 5-Aminoisoquinolinone-treated HT-29 cell group than that in 5-Aminoisoquinolinoneuntreated groups. Conclusion: The data suggest that 5-Aminoisoquinolinone can inhibit the adhesion of HT-29 cells to human umbilical vein endothelial cells. 5-Aminoisoquinolinone also can inhibit poly (adenosine 5'-diphosphate ribose) polymerase activation and the expressions of ICAM-1 and P-selectin in HT-29 cells. 5-Aminoisoquinolinone probably contributes to the prevention of tumor cell metastasis. Further study is needed. 相似文献
24.
法莫替丁冲剂在健康人中的生物利用度及药动学研究 总被引:1,自引:0,他引:1
本实验采用反相高效液相色谱法,比较了10名健康志愿者单剂量口服法莫替丁冲剂及等剂量片剂的生物利用度。结果表明:二种剂型的Tmax,Cmax,AUC均无显著性差异(P〉0.05)。冲剂相对于与片剂的相对生物利用度F=101.90。 相似文献
25.
Robert A. Schnoll Ph.D. James Calvin B.A. Michael Malstrom B.S. Randi L. Rothman B.A. Hao Wang M.S. James Babb Ph.D. Suzanne M. Miller Ph.D. John A. Ridge M.D. Ph.D. Benjamin Movsas M.D. Corey Langer M.D. Michael Unger M.D. Melvyn Goldberg M.D. 《Annals of behavioral medicine》2003,25(3):214-221
Even though continued smoking by cancer patients adversely affects survival and quality of life, about one third of patients
who smoked prior to their diagnosis continue to smoke after their diagnosis. The implementation of smoking cessation treatments
for cancer patients has been slowed by the lack of data on correlates of tobacco use in this population. Thus, this longitudinal
study assessed demographic, medical, addiction, and psychological predictors of tobacco use among 74 head, neck, and lung
cancer patients. Multivariable binary logistic regression analyses, with outcome categorized as smoker or nonsmoker, indicated
that the likelihoodthat patients would be a smoker was associated with lower levels of perceived risk and a higher level of
quitting cons. Multivariable nominal logistic regression, with outcome classified as continuous smoker, continuous quitter,
relapser, or follow-up quitter, indicated that: (a) patients categorized as continuous smokers reported significantly lower
quitting self-efficacy than follow-up quitters and continuous quitters, (b) relapsers reported a significantly lower level
of quitting self-efficacy than either follow-up quitters or continuous quitters, and (c) continuous smokers exhibited a significantly
lower level of risk perceptions than continuous abstainers. These findings can be useful for the development and evaluation
of treatments to promote smoking cessation among cancer patients.
Support for this study was provided by National Institutes of Health Grants CA57708, CA06927, CA88610, CA95678, and CA76644. 相似文献
26.
Zhang Gui-mei Hao Tian-ling Yang Yu-zhen Feng Zuo-hua Jiang Zhi-yao Zhou Bin Zhang Hui 《华中科技大学学报(医学英德文版)》1992,12(3):150-153
Summary Effects of Chinese Medicinal Preparation “Re Du Qing” (RDQ) on the activation, proliferation and membrane fluidity of T lymphocytes
from human peripheral blood Were studied by means of3H-TdR incorporation and DPH fluorescence polarization. The results showed that “RDQ” can:1) significantly inhibit the activation
of T lymphocytes; 2) restrain the proliferation of activated T lymphoblasts in the presence of exogenous interleukin-2 (IL-2);
and 3) increase the membrane fluidity of T lymphocytes and antagonize the decreased fluidity of lymphocyte membrane mediated
by Con A or PHA. The functional abnormalities of T lymphocytes in some autoimmune diseases such as arthritis and the usefulness
of RDQ in the treatment of these diseases were also discussed. 相似文献
27.
新型脊柱固定器械的研制与临床应用 总被引:21,自引:0,他引:21
自1989年以来,临床应用一种新型脊柱固定器械,共68例,其中52例为胸腰椎骨折,16例为椎体滑脱。经临床观察和随访,治疗效果满意。这种新型固定器械,既可行胸腰椎骨折的固定,也可行椎体滑脱的复位。根据临床需要,该器械可行压缩、撑开、成角和中立位固定。作者强调,脊柱损伤只要有手术指征,手术时机甚为重要,应早期或立即手术,有利于脊柱骨折和椎管前方骨块的复位,早期也有利于神经功能的恢复。 相似文献
28.
Intracellular metabolism and mechanism of anti-retrovirus action of 9-(2-phosphonylmethoxyethyl)adenine, a potent anti-human immunodeficiency virus compound. 总被引:11,自引:0,他引:11 下载免费PDF全文
29.
目的 探讨原发性十二指肠肿瘤 (PTD)的诊断和治疗。方法 回顾性分析我院 1995 2 0 0 3年间 4 3例PTD的临床资料。结果 十二指肠镜确诊率为 85 .7% ,B超检查的阳性率为 5 5 .6 % ,CT检查阳性率为 80 % ,肿瘤位于十二指肠降段 (乳头部或其对侧 ) 35例 ,占 81.4 % ,2例平滑肌瘤切除术后存活 5年以上 ,1例乳头部腺瘤行肿瘤局部切除术后半年出现黄疸 ,病因不详。 4例间质瘤均健在且生存 16 2 1个月 ,36例原发性十二指肠恶性肿瘤中胰头十二指肠切除 18例 ,节段切除 1例 ,手术切除率为 5 1.2 %。结论 B超、CT、纤维十二指肠镜检查是诊断PTD的主要手段。手术切除是最基本有效的治疗方法。对于良性肿瘤可行局部肿瘤切除、十二指肠节段切除或经内镜切除。对于恶性肿瘤 ,胰十二指肠切除术是首选术式。 相似文献
30.
本文采用放射免疫法测定了144例恶性肿瘤患者血清CEA含量,并以同样条件测定了30例正常人作为对照。结果表明恶性肿瘤患者血清CEA含量显著高于健康人,均值为10.3±4.84ng/ml。不同肿瘤患者血清CEA升高的程度不等,其中以肺癌含量最高为14.7±7.83ng/ml。转移性肿瘤CEA含量高于144例肿瘤的平均水平。术后复发者含量不见下降。癌性胸腹水中CEA含量明显升高。因此,血清CEA的测定对恶性肿瘤的辅助诊断,评价疗效和判断预后具有重要的临床意义。 相似文献