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81.
Bioavailability and absorption kinetics of nicotine following application of a transdermal system. 总被引:1,自引:0,他引:1 下载免费PDF全文
S K Gupta N L Benowitz P Jacob rd C N Rolf J Gorsline 《British journal of clinical pharmacology》1993,36(3):221-227
1. The absolute bioavailability and absorption kinetics of nicotine were investigated in 13 healthy adult male smokers following single and multiple applications of a nicotine transdermal system (NTS), designed to release nicotine at an approximate rate of 1.5 mg h-1 over 24 h. The absorption of nicotine from the single NTS application was calculated with reference to a simultaneous intravenous infusion (i.v.) of deuterium-labelled nicotine. 2. The mean input time (MIT) and mean absorption time (MAT) for nicotine following application of NTS for 24 h were 7.7 and 4.2 h, respectively. 3. Following NTS removal, the mean apparent nicotine elimination half-life was 2.8 h, compared with 2.0 h following i.v. nicotine, reflecting continued absorption of nicotine following NTS removal. 4. The mean amount of nicotine absorbed from the NTS after the 24 h application was 20.9 mg, which represents about 68% of the amount released from the system; the remaining 32% was lost from the system during daily activities. 5. The ratio of AUC values for the metabolite cotinine relative to nicotine was similar whether nicotine was administered transdermally or intravenously. 6. Following i.v. administration, the mean nicotine clearance was 72 l h-1 (coefficient of variation 29%). Since coefficients of variation in AUC values following NTS and i.v. treatments were similar, transdermal administration of nicotine was not associated with increased interindividual variability in plasma nicotine concentrations. 7. No significant changes were seen in the pharmacokinetics of nicotine between single and multiple applications of NTS. 8. As expected from the higher total plasma nicotine concentrations, the incidence of adverse effects was higher following simultaneous intravenous and transdermal administration of nicotine. The most frequently reported systemic side effects were nervousness and headache: mild itching was the most frequent topical effect. 相似文献
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83.
间硝地平对左室肥厚大鼠左室舒张功能及心脑线粒体和血管组织钙含量的影响 总被引:1,自引:0,他引:1
用肾性高血压左室肥厚(LVH)大鼠模型,观察了间硝地平(m-Nif)和硝苯地平(Nif)长期给药(ig20mg·kg-1·d-1持续9周)对左室舒张功能、左心室肌和大脑线粒体及血管钙含量的影响。与假手术组相比,LVH组左室顺应性明显下降,僵硬度增高,左心室肌和大脑线粒体及尾动脉和主动脉钙含量增加。与LVH组相比,m-Nif和Nif各组左室顺应性改善,僵硬度降低(P<0.01),左心室肌线粒体及尾动脉和主动脉钙含量较LVH组显著降低(P<0.01)。两药在作用强度上无显著差异。 相似文献
84.
The development of a method to facilitate clinical negotiationwith diabetic patients is described. The principles of the methodincorporate patient centredness, an assessment of readinessto change and some elements of motivational interviewing. Asimple low cost technology is part of the innovative method.Details of the method and its application are published beforethe results of a randomized controlled trial to ensure thatthe techniques are in the public domain before the outcome ofthe trial is known. 相似文献
85.
Manna R; Todaro L; Latteri M; Gambassi G; Massi G; Grillo MR; Romito A; Caputo S; Gasbarrini GB 《Rheumatology (Oxford, England)》1997,36(1):124-125
The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but
recently hepatitis C virus (HCV) has been suggested as trigger of
autoimmunity. We report a case of a 26-yr-old patient with purpura due to
leucocytoclastic vasculitis associated with hepatitis C virus infection.
Laboratory findings showed AST, ALT, gamma GT within normal limits,
positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction
for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti- cardiolipin
antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic
antibodies with perinuclear pattern were also present. A skin biopsy
specimen of a purpuric lesion showed leucocytoclastic vasculitis with small
vessel thrombosis and perivascular deposition of IgM and fibrinogen on
immunofluorescence study. This case shows a role of HCV in leucocytoclastic
vasculitis; it is possible that this HCV can induce autoimmunity
independently of cryoglobulins and liver involvement.
相似文献
86.
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus. 相似文献
87.
G Micali † MR Nasca † R De Pasquale † D Innocenzi‡ 《Journal of the European Academy of Dermatology and Venereology》2003,17(3):320-323
Kaposi's sarcoma is a vascular tumour of multifocal origin occurring primarily on the extremities. The case of a 45-year-old HIV negative and HHV-8 positive man with an asymptomatic reddish macular lesion on the inner layer of the prepuce is described. Although primary penile Kaposi's sarcoma is a relatively uncommon disorder in HIV negative men, dermatologists and venereologists should consider this possibility when treating non-specific penile lesions. A minimal penile lesion with non-distinctive clinical features may sometimes be the exclusive manifestation of Kaposi's sarcoma, making histologic evaluation necessary to establish the diagnosis. 相似文献
88.
MR Carvalho ; MA Krieger ; E Almeida ; W Oelemann ; MA Shikanai-Yassuda ; AW Ferreira ; JB Pereira ; A Saez-Alquezar ; PE Dorlhiac-Llacer ; DF Chamone ; et al. 《Transfusion》1993,33(10):830-834
Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease. 相似文献
89.
90.
Ruffin MT Hade EM Gorsline MR DeGraffinreid CR Katz ML Kobrin SC Paskett ED 《Vaccine》2012,30(36):5349-5357