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991.
Weijia Zheng Dorothea Sauer James W McGinity 《European journal of pharmaceutics and biopharmaceutics》2005,59(1):147-154
The objective of this study was to investigate the influence of a hydrophilic polymer, hydroxyethylcellulose (HEC), on the release properties of theophylline from pellets coated with Eudragit RS 30 D, and the physicochemical properties of Eudragit RS 30 D cast films. The release rate of theophylline from Eudragit RS 30 D coated pellets decreased during storage at 25 degrees C/60% RH due to the further coalescence of colloidal acrylic particles. In addition, water-vapor permeability and tensile strength of Eudragit RS 30 D cast film decreased after 1-month storage at 25 degrees C/60% RH. The presence of 10% hydroxyethylcellulose in the coating formulation was shown to stabilize the drug release rate from coated pellets, the water-vapor permeability and the tensile strength of free films. Atomic force microscopy and scanning electronic microscopy were used to demonstrate that the HEC was immiscible with Eudragit RS 30 D in the cast films. The stabilization effect of HEC was investigated and determined to be due to the formation of an incompatible phase between the latex particles which impaired further coalescence of the colloidal acrylic particles. 相似文献
992.
目的:建立RP-HPLC法测定曲匹布通及其有关物质含量。方法:选用Diamond C_(18)柱(250mm×4.6mm,5μm),甲醇-磷酸二氢钾缓冲液(取磷酸二氢钾1.36g加水至1000mL,用磷酸调pH至3.0)(60∶40)为流动相,检测波长271nm,流速:1.0mL·min~(-1),柱温:30℃。结果:曲匹布通在0.08296-0.4148μg·mL~(-1)范围内,线性关系良好,回归方程Y=1869121X-3796,r=0.9999。平均回收率为99.8%(n=6)。结论:本法准确、灵敏、简便。 相似文献
993.
穴位埋线对慢性胃炎患者环核苷酸及胃肠激素的影响 总被引:4,自引:0,他引:4
目的:观察穴位埋线治疗慢性胃炎的临床疗效.方法:将70例慢性胃炎患者随机分为埋线组(36例)与针刺组(34例).主穴均为胃俞、中脘、足三里,分别进行埋线或针刺治疗,并观察血浆环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)含量及胃泌素(Gas)、P物质(SP)含量的改变.结果:埋线组总有效率为88.89%优于针刺组76.47%(P<0.05);两组各自治疗前后比较,血浆cAMP、cGMP、Gas、SP含量的改变差异具有非常显著性意义(P<0.01);埋线组各项指标的改善程度均优于针刺组(P<0.05).结论:穴位埋线治疗慢性胃炎有肯定疗效,通过调节环核苷酸和胃肠激素含量,从而改善了神经-内分泌-免疫调节功能. 相似文献
994.
近代著名医家祝味菊,生性慧敏又好学不倦。研读医经,披阅不倦,博览群书,独具见解,融汇中西,悟出新意,另树一帜,倡温热潜阳扶正之法,临证以敢用、广用、善用附子而著名。文中介绍了祝味菊先生治疗耳鸣目眩心悸案、鼻衄案及胃痞案三则案例,通过对案例的分析研究,从中可以领略到祝先生治病注重人体阳气,独具一格,胆大心细的医家风范。值得注意的是祝味菊先生强调:服用各类附子要注意须以热水煮半小时以上,再纳它药同煎;其中附子又以川产黄附片,乃盐卤所别,其性纯正,为附子中佳品;使用附子时要善去其急暴,制暴为良,每因配伍而异用之,实属经验之谈。 相似文献
995.
霍乱是烈性传染病,自从1821年传入我国出现首次大流行之后,此病在中国危害多年,直到解放后才得到基本控制.百馀年来,中医在治疗霍乱方面积累了不少经验,出现了许多专著.由于各人治疗经验不同,在治疗霍乱方面形成主寒、主热两大派,论争不休. 相似文献
996.
RAS mutation is associated with hyperdiploidy and parental characteristics in pediatric acute lymphoblastic leukemia. 总被引:1,自引:0,他引:1
J L Wiemels Y Zhang J Chang S Zheng C Metayer L Zhang M T Smith X Ma S Selvin P A Buffler J K Wiencke 《Leukemia》2005,19(3):415-419
We explored the relationship of RAS gene mutations with epidemiologic and cytogenetic factors in a case series of children with leukemia. Diagnostic bone marrow samples from 191 incident leukemia cases from the Northern California Childhood Leukemia Study were typed for NRAS and KRAS codon 12 and 13 mutations. A total of 38 cases (20%) harbored RAS mutations. Among the 142 B-cell acute lymphoblastic leukemia (ALL) cases, RAS mutations were more common among Hispanic children (P=0.11) or children born to mothers <30 years (P=0.007). Those with hyperdiploidy at diagnosis (>50 chromosomes) had the highest rates of RAS mutation (P=0.02). A multivariable model confirmed the significant associations between RAS mutation and both maternal age and hyperdiploidy. Interestingly, smoking of the father in the 3 months prior to pregnancy was reported less frequently among hyperdiploid leukemia patients than among those without hyperdiploidy (P=0.02). The data suggest that RAS and high hyperdiploidy may be cooperative genetic events to produce the leukemia subtype; and furthermore, that maternal age and paternal preconception smoking or other factors associated with these parameters are critical in the etiology of subtypes of childhood leukemia. 相似文献
997.
Cigarette smoking and risk of non-Hodgkin lymphoma: a pooled analysis from the International Lymphoma Epidemiology Consortium (interlymph). 总被引:5,自引:0,他引:5
Lindsay M Morton Patricia Hartge Theodore R Holford Elizabeth A Holly Brian C H Chiu Paolo Vineis Emanuele Stagnaro Eleanor V Willett Silvia Franceschi Carlo La Vecchia Ann Maree Hughes Wendy Cozen Scott Davis Richard K Severson Leslie Bernstein Susan T Mayne Fred R Dee James R Cerhan Tongzhang Zheng 《Cancer epidemiology, biomarkers & prevention》2005,14(4):925-933
BACKGROUND: The International Lymphoma Epidemiology Consortium (InterLymph) provides an opportunity to analyze the relationship between cigarette smoking and non-Hodgkin lymphoma with sufficient statistical power to consider non-Hodgkin lymphoma subtype. The results from previous studies of this relationship have been inconsistent, likely due to the small sample sizes that arose from stratification by disease subtype. To clarify the role of cigarette smoking in the etiology of non-Hodgkin lymphoma, we conducted a pooled analysis of original patient data from nine case-control studies of non-Hodgkin lymphoma conducted in the United States, Europe, and Australia. METHODS: Original data were obtained from each study and uniformly coded. Risk estimates from fixed-effects and two-stage random-effects models were compared to determine the impact of interstudy heterogeneity. Odds ratios (OR) and 95% confidence intervals (95% CI) were derived from unconditional logistic regression models, controlling for study center, age, sex, and race. RESULTS: In our pooled study population of 6,594 cases and 8,892 controls, smoking was associated with slightly increased risk estimates (OR, 1.07; 95% CI, 1.00-1.15). Stratification by non-Hodgkin lymphoma subtype revealed that the most consistent association between cigarette smoking and non-Hodgkin lymphoma was observed among follicular lymphomas (n = 1452). Compared with nonsmokers, current smokers had a higher OR for follicular lymphoma (1.31; 95% CI, 1.12-1.52) than former smokers (1.06; 95% CI, 0.93-1.22). Current heavy smoking (> or = 36 pack-years) was associated with a 45% increased OR for follicular lymphoma (1.45; 95% CI, 1.15-1.82) compared with nonsmokers. CONCLUSIONS: Cigarette smoking may increase the risk of developing follicular lymphoma but does not seem to affect risk of the other non-Hodgkin lymphoma subtypes we examined. Future research is needed to determine the biological mechanism responsible for our subtype-specific results. 相似文献
998.
The association of XRCC1 haplotypes and chromosomal damage levels in peripheral blood lymphocyte among coke-oven workers. 总被引:1,自引:0,他引:1
Shuguang Leng Juan Cheng Linyuan Zhang Yong Niu Yufei Dai Zufei Pan Bin Li Fengsheng He Yuxin Zheng 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1295-1301
Theoretically, a haplotype has a higher level of heterozygosity than individual single nucleotide polymorphism (SNP) and the association study based on the haplotype may have an increased power for detecting disease associations compared with SNP-based analysis. In this study, we investigated the effects of four haplotype-tagging SNPs (htSNP) and the inferred haplotype pairs of the X-ray cross-complementing group 1 (XRCC1) gene on chromosome damage detected by the cytokinesis-block micronucleus assay. The study included 141 coke-oven workers with exposure to a high level of polycyclic aromatic hydrocarbons and 66 nonexposed controls. The frequencies of total MN and MNed cells were borderline associated with the Arg(194)Trp polymorphism (P = 0.053 and P = 0.050, respectively) but not associated with the Arg(280)His, Arg(399)Gln and Gln(632)Gln polymorphisms among coke-oven workers. Five haplotypes, including CGGG, TGGG, CAGG, CGAG, and CGGA, were inferred based on the four htSNPs of XRCC1 gene. The haplotype CGGG was associated with the decreased frequencies of total MN and MNed cells, and the haplotypes TGGG and CGAG were associated with the increased frequencies of total MN and MNed cells with adjustment for covariates among coke-oven workers. This study showed that the haplotypes derived from htSNPs in the XRCC1 gene were more likely than single SNPs to correlate with the polycyclic aromatic hydrocarbon-induced chromosome damage among coke-oven workers. 相似文献
999.
16例直肠腺瘤的CT影像分析 总被引:1,自引:0,他引:1
[目的]探讨直肠腺瘤的CT表现.[方法]对16例经病理证实的直肠腺瘤CT表现进行回顾性分析.[结果]16例腺瘤按病理类型分为绒毛状腺瘤,管状绒毛状腺瘤和管状腺瘤,其中8例恶变.CT征象如下:广基生长有8例,窄基带蒂生长的5例,环壁增厚的有4例;向腔内匍匐式或菜花状生长的有10例;占肠周径比率在1/3以下的9例;病灶与直肠壁相贴时留下通气的间隙7例,可作为直肠腺瘤的特征性表现.[结论]一般直肠腺瘤均具有典型的CT表现,术前明确的腺瘤的CT诊断对于手术方式有重要影响. 相似文献
1000.
GM-CSF基因重组腺病毒载体的构建及鉴定 总被引:2,自引:0,他引:2
目的:构建人粒细胞-巨噬细胞集落刺激因子(GM-CSF)基因的重组腺病毒载体,为进一步研究GM-CSF基因在肿瘤基因治疗中的应用提供实验基础。方法:采用PCR方法,从重组质粒pcDNA3.1-GM-CSF扩增出GM-CSF基因片段,通过穿梭质粒pShuttle,将带有CMV启动子的目的片段克隆入Adeno-X腺病毒DNA中,获得重组腺病毒DNA,通过脂质体转染HEK293细胞,经包装扩增后,获得重组腺病毒Adeno-X-GM-CSF,PCR鉴定,ELISA法检测表达产物。结果:含GM-CSF基因的重组腺病毒Adeno-X-GM-CSF构建成功,经PCR鉴定和DNA测序等证实了其正确性,重组腺病毒上清液中GM-CSF表达量达26ng/mL。结论:含GM-CSF基因的重组腺病毒构建成功。 相似文献