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71.
Bill J Gurley Ashley Swain Gary W Barone D Keith Williams Philip Breen C Ryan Yates Leslie B Stuart Martha A Hubbard Yudong Tong Sreekhar Cheboyina 《Drug metabolism and disposition》2007,35(2):240-245
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo. 相似文献
72.
淋巴瘤样肉芽肿与韦格内肉芽肿临床特点的比较 总被引:2,自引:0,他引:2
目的 总结淋巴瘤样肉芽肿病(lym phom atoid granulom atosis,LG)与韦格内肉芽肿( egener granulo Wm atosis,W G)的临床特点,从临床上加以鉴别。 方法 回顾性总结我院与北京协和医院 1989 年以来收治的 6 例 LG和20 例 W G 患者的临床资料,并进行比较。 结果 发热、咳嗽及呼吸困难在 LG 中较常见,流涕、鼻衄及关节痛以W G 为多,肺受累以 LG 为多,耳鼻喉、眼及肾病变在 W G 中明显增多,皮肤受损两者相似。W G 患者常有 c-ANCA 阳性及尿沉渣异常。 LG X 线胸片为双侧多发结节,边界不清,多无肺门、纵隔淋巴结肿大; G 则为双侧多发边界清晰W的结节, 易形成空洞, 肺门和纵隔淋巴结可肿大。LG 病理改变为血管中心性淋巴增生性病变, 浸润的细胞主要是小淋巴细胞和不同数量大的不典型淋巴细胞; 而在 W G 中可见坏死性血管炎及大量中性白细胞、浆细胞及少量嗜酸细胞浸润形成的肉芽肿, 部分有多核巨细胞。W G 经治疗后, 多数患者病情缓解; 则疗效不佳。 结论 LG 和 W G 在临 LG床表现、实验室检查、 影像及病理诸方面的差异有利于两者的鉴别诊断。 相似文献
73.
室间隔夹层瘤的超声诊断(附4例报告) 总被引:1,自引:0,他引:1
目的 总结室间隔夹层瘤的超声心动图诊断及临床应用价值。方法1985~2005年超声诊断罕见的室间隔夹层瘤4例。超声主要取左室长轴、四腔心、五腔心、大动脉短轴及非标准切面,观察主动脉窦的形态及结构:如扩张窦瘤的大小、窦壁厚度、窦瘤破口的部位、窦瘤破口与室间隔之间的关系,主动脉窦瘤与室间隔夹层瘤之间交通口的大小,测量形成室间隔夹层瘤的大小及夹层瘤左、右室面的厚度,结合彩色多普勒观察心动周期夹层瘤与主动脉窦瘤血流动态变化,频谱多普勒测量窦瘤与室间隔夹层瘤之间的血流速度。结果4例室间隔夹层瘤均为主动脉右窦破人室间隔基底段,且均行手术治疗证实超声诊断。结论超声心动图对室间隔夹层瘤可直接做出诊断,超声诊断价值在于早发现、早诊断、及早治疗,并可为外科选择手术方式提供重要的有价值的依据。 相似文献
74.
David M Raffel Robert A Koeppe Roderick Little Chia-Ning Wang Suyu Liu Larry Junck Mary Heumann Sid Gilman 《Journal of nuclear medicine》2006,47(11):1769-1777
Scintigraphic imaging with (123)I-metaiodobenzylguanidine ((123)I-MIBG) has demonstrated extensive losses of cardiac sympathetic neurons in idiopathic Parkinson's disease (IPD). In contrast, normal cardiac innervation has been observed in (123)I-MIBG studies of multiple-system atrophy (MSA) and progressive supranuclear palsy (PSP). Consequently, it has been hypothesized that cardiac denervation can be used to differentiate IPD from MSA and PSP. We sought to test this hypothesis by mapping the distribution of cardiac sympathetic neurons in patients with IPD, MSA, and PSP by using PET and (11)C-meta-hydroxyephedrine ((11)C-HED). Also, the relationship between cardiac denervation and nigrostriatal denervation was investigated by measuring striatal presynaptic monoaminergic nerve density with PET and (11)C-dihydrotetrabenazine ((11)C-DTBZ). METHODS: (11)C-HED and (11)C-DTBZ scans were obtained for patients with IPD (n = 9), MSA (n = 10), and PSP (n = 8) and for age-matched control subjects (n = 10). Global and regional measurements of (11)C-HED retention were obtained to assess the extent of cardiac sympathetic denervation. (11)C-DTBZ binding was measured in the caudate nucleus, anterior putamen, and posterior putamen. RESULTS: As expected, extensive cardiac denervation was observed in several of the patients with IPD. However, substantial cardiac denervation was also seen in some patients with MSA and PSP. (11)C-DTBZ studies demonstrated striatal denervation in all patients with IPD and in most patients with MSA and PSP. No correlation was found between cardiac (11)C-HED retention and striatal (11)C-DTBZ binding. CONCLUSION: Cardiac sympathetic denervation was found to occur not only in IPD but also in other movement disorders, such as MSA and PSP. This finding implies that scintigraphic detection of cardiac sympathetic denervation cannot be used independently to discriminate IPD from other movement disorders, such as MSA and PSP. Cardiac sympathetic denervation was not correlated with striatal denervation, suggesting that the pathophysiologic processes underlying cardiac denervation and striatal denervation occur independently in patients with parkinsonian syndromes. These findings provide novel information about central and peripheral denervation in patients with neurodegenerative disorders. 相似文献
75.
76.
Delta hepatitis virus infection in China 总被引:1,自引:0,他引:1
D Q Wang H H Cheng G Y Minuk L H Liu C M Anand T C Stowe H X Wang D C Ying Y R Tu K A Buchan 《International journal of epidemiology》1987,16(1):79-83
To assess the prevalence, epidemiological features and prognostic implications of hepatitis D (Delta) in Sichuan Province, The People's Republic of China, 649 sera (515 from HBsAg positive patients and 134 from HBsAg negative subjects) were tested by radioimmunoassay (RIA) for antibody to the hepatitis D virus (anti-HD). Forty-seven sera (7.2%) showed some degree of reactivity. Serial dilutions of these sera indicated that prozoning was not responsible for the equivocal results. Thirty-four of the 47 sera were submitted under code to a second laboratory for independent analysis. According to those results anti-HD antibodies were detected in four of these sera. The overall prevalence of anti-HD in the HBsAg positive patients therefore was 0.8% (4/515). On the basis of clinical, biochemical and histological data 427 HBsAg positive sera were further divided into acute Type B hepatitis, chronic Type B hepatitis, healthy carrier state and hepatocellular carcinoma (HCC) subgroups. Two of 65 (3.1%) anti-HD positive sera belonged to the acute Type B hepatitis group; one of 104 (0.9%), the chronic Type B hepatitis group and one of 246 (0.4%), the healthy carrier group. No antibody was detected in sera from 12 HBsAg positive HCC patients. All HBsAg negative patients were negative for anti-HD antibody. The results of this study indicate that despite a high prevalence of hepatitis B virus infection, positive serology for delta virus is uncommon in Sichuan Province, The People's Republic of China. 相似文献
77.
78.
目的 初步建立阴道粘膜上皮细胞体外培养方法,为阴道粘膜上皮研究提供实验模型.方法 取雌性新西兰大白兔阴道粘膜组织小块,胶原酶Ⅳ和胰蛋白酶联合消化分离法收集上皮细胞,接种于角朊细胞无血清培养液中静置培养、传代.动态观察细胞生长增殖情况,扫描和透射电镜观察超微结构,流式细胞仪测定细胞增殖周期,并进行免疫组织化学鉴定.结果 体外培养的阴道粘膜上皮细胞为二倍体细胞,增殖状态良好,细胞间可见桥粒连接,免疫组化角蛋白染色阳性.细胞的超微结构和免疫组化染色均具有上皮细胞特征.结论 在本实验条件下,体外培养的阴道粘膜上皮细胞具有较好的增殖能力,可作为阴道粘膜上皮研究的理想实验模型. 相似文献
79.
80.
目的:建立乳腺非典型增生病动物模型,探讨非典型增生与血管生成的关系。方法:采用灌服二甲基苯蒽+颈部枷具方法复制大鼠肝郁血瘀型乳腺非典型增生动物模型,并给予中药乳复汤治疗。常规染色观察大鼠乳腺组织病理组织形态.免疫组化方法检测MVD、VEGF和bFGF的表达。结果:病证模型组乳腺非典型增生率90%.较单纯造模组高.P=0.0415;中药乳复汤治疗组非典型增生率较病证模型组低.P=0.0459;随着一般增生到非典型增生程度加重,MVD计数增多,VEGF、bFGF的表达升高,P〈0.05。结论:病证结合造模更适合中医动物实验要求,中药乳复汤具有抑制血管生成作用。 相似文献