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991.
目的:研究慢性阻塞性肺病(COPD)患者合用硝苯地平前后茶碱稳态血药浓度及药物动力学的变化。方法:高效液相色谱(HPLC)法测定9名COPD患者po茶碱片(200 mg,tid)5 d后及加服硝苯地平(10 mg,tid)5 d后茶碱血药浓度,以PKBP-N1计算机程序拟合药物动力学参数。结果:COPD患者合用硝苯地平5 d后,茶城稳态平均血药浓度下降1.77士2.04 mg/L,cmax和AUC0~8均较用硝苯地平前降低,分别为12.3士6.5和9.9士4.9 mg/L,82.4士52.1和62.5士38.8(mg?h)/L(P<0.05)。其它药物动力学参数无明显改变(P>0.05)。结论:COPD患者合并使用硝苯地平,无需改变氨茶碱的治疗剂量,两药可以合用。 相似文献
992.
D W Man M H Hamdy G M Hendry W H Bisset J O Forfar 《Archives of disease in childhood》1983,58(9):709-712
A retrospective study was made of 9 patients with congenital lobar emphysema who presented over the past 13 years. The ages of the patients at diagnosis ranged from 2 weeks to 10 years. The earlier the presentation, the more severe were the symptoms. Two patients were misdiagnosed initially at the referring hospitals with near disastrous results. Pitfalls in diagnosis are outlined and the various investigative procedures discussed. A flow chart for the diagnostic approach is presented. Treatment was usually by lobectomy but 2 older children presenting late with mild symptoms were managed conservatively with satisfactory results. 相似文献
993.
Intra-aortic balloon pumps (IABPs) cannot sustain hemodynamics if the left heart is severely injured. An enhanced IABP was evaluated in 6 anesthetized dogs with acute stenosis of the left anterior descending coronary artery, regional left ventricular (LV) stunning, and global LV dysfunction. An IABP balloon was inserted into the descending aorta and an external chamber containing another IABP balloon was connected to the aorta through a catheter inserted into the left subclavian artery. This emulated the enhanced IABP with a conduit from its external chamber passing axially through an internal IABP balloon. Compared to IABP, enhanced IABP improved hemodynamics and LV function in all conditions. During severe LV dysfunction and circulatory failure, IABP failed to augment diastolic aortic pressure or improve coronary and carotid flows. Enhanced IABP augmented diastolic pressure from 32 +/- 3 mm Hg to 87 +/- 2 mm Hg and increased coronary and carotid flows. Enhanced IABP may be a lifesaving device for patients with severe LV failure. 相似文献
994.
This paper presents the velocity measurements in the gap between the impeller and the pump casing of a 5:1 enlarged centrifugal blood pump model at operating condition. Both the radial and tangential velocity at the gap were measured. It was found that there was no cross flow in both the radial and tangential velocity distributions at the seven radial locations. This implies that the 0.2 mm gap in the prototype should be the optimal clearance of the pump. The vector plot of the resultant velocity showed that the double volute design of the pump, especially the splitter plate that started at theta; = 180 degrees, has created a washout mechanism in the clearance gap; that is, a sector of flow ranging from theta; = 100 degrees to theta; = 190 degrees has directed strongly toward the eye while the rest of the flow in the gap is in a tangential direction. It is important that the blood should flow out of the gap through the eye instead of continuing to circulate in the clearance gap. This explains why the pump has minimum hemolysis and thrombus formation and is able to function with nominal efficiency as compared to other centrifugal pumps. 相似文献
995.
Cox WM Schippers GM Klinger E Skutle A Stuchlíková I Man F King AL Inderhaug R 《Journal of studies on alcohol》2002,63(3):280-285
OBJECTIVE: The ability of motivational structure and other variables to predict alcohol consumption was assessed in university students (N = 370; 244 women) in the Czech Republic, The Netherlands, Norway and the United States. METHOD: Motivational structure was assessed with the Motivational Structure Questionnaire (MSQ), which inquires about respondents' individual personal concerns in various areas of life and dimensions of their goal strivings related to the resolution of concerns. Alcohol-related problems were measured with the Short Michigan Alcoholism Screening Test. RESULTS: Factor analysis of MSQ indices yielded a two-factor solution, one factor of which reflects an adaptive motivational structure marked by elements necessary for attaining psychologically satisfying resolutions of personal concerns. The other factor reflects a more maladaptive motivational structure marked by feelings of indifference about the achievement of personal goals. As hypothesized, MSQ Factor I was a significant inverse predictor of the amount of alcohol that students drank, but only among those who experienced alcohol-related problems. CONCLUSIONS: The similarity in results across culturally varied samples suggests the robustness of the relationships for understanding the motivational bases for alcohol use. 相似文献
996.
Contents of four active components in different commercial crude drugs and preparations of Danshen (Salvia miltiorrhiza) 总被引:5,自引:1,他引:4
Zhang H Yu C Jia JY Leung SW Siow YL Man RY Zhu DY 《Acta pharmacologica Sinica》2002,23(12):1163-1168
AIM:To detect the contents of four active components of Salvia miltiorrhiza in various commercially available danshen crude drugs and preparations.METHODS:Commercially available danshen crude drugs from different sources,as well as danshen pills and intravenous injection preparations containing danshen alone or in combination with other herbs were collected.The composition of these danshen samples was analyzed using HPLC.Specifically,the amounts of magnesium tanshinoate B(MTB),danshensu,isotanshinone IIA,and cryptotanshinone were determined.In some of these samples,the content of MTB was further confirmed by liquid chromatography-tandem mass spectrometer (LC-MS)/MS method.RESULTS:There were great variations in the amount of the four active ingredients in the commercially available danshen crude drugs and drug preparations in this study.The amount of MTB was the highest among the four components measured in the crude drugs.However,the amounts of MTB in all danshen preparations were much lower than those in crude drugs.The 2 lipophilic components,isotanshinone IIA and cryptotanshinone,were very low or not detectable in both injection and oral preparations.CONCLUSION:MTB can be used to standardize the various forms of danshen crude drugs and drug preparations from different sources.In view of the variation in the amounts of MTB and other components,improvement in the production methods of danshen preparations is essential to ensure consistent amount of its active ingredients and reproducible pharmacological actions. 相似文献
997.
To evaluate the efficacy of Chinese medicine (CM) acupuncture for chronic neck pain (CNP), a single blind, controlled, crossover, clinical trial was undertaken. Twenty-nine volunteers with CNP were randomly recruited into two groups. Both groups received two phases of treatment with a washout period between the two phases. Group A (14 volunteers) received CM acupuncture in the first phase and sham acupuncture in the second, while Group B (15 volunteers) received sham in the first and real in the second. CM acupuncture was individualized and consisted of nine sessions on both local and distal points. Manual twisting of the needle was applied on all points plus strong electrical stimulation of distal points in CM acupuncture. Sham acupoints (lateral to the real) and sham (weak) electrical stimulation was used in the control group. Comparison of subjective and objective measures between the two groups was made at different periods, including baseline, after each phase of treatment, after washout, and after the 16th week follow-up. The subjective measures included pain intensity, duration per day, analgesic medication count, visual analogue scales (VAS) and neck disability index (NDI). The objective measures consisted of neck range of motion (ROM) and pain threshold (PT). Both the real and sham treatments significantly reduced subjective pain, without significant differences between groups for most subjective measures. Objective measures showed no significant change for either group before and after each period or by inter-groups analysis. A minimum 16-week effect of both real and sham acupuncture was found for subjective measures in the follow-up periods. Further study is recommended with an increased sample size, a longer washout period, and a longer baseline period. 相似文献
998.
999.
The recovery cycle of auditory neurons is an important neuronal property, which determines a neuron's ability to respond to pairs of sounds presented at short inter-sound intervals. This property is particularly important for bats, which rely upon analysis of returning echoes to extract the information about targets after emission of intense orientation sounds. Because target direction often changes throughout the course of hunting, the changing echo direction may affect the recovery cycle and thus temporal processing of auditory neurons. In this study, we examined the effect of sound azimuth on the recovery cycle of inferior collicular (IC) neurons in the big brown bat, Eptesicus fuscus, under free-field stimulation conditions. Our study showed that the recovery cycle of most IC neurons (42/49, 86%) was longer when determined with sounds delivered at 40 degrees ipsilateral (i40 degrees ) than at 40 degrees contralateral (c40 degrees ) to the recording site. To study the contribution of GABAergic inhibition to sound azimuth-dependent recovery cycle, we compared the recovery cycle of IC neurons determined at two sound azimuths before and during iontophoretic application of bicuculline, an antagonist for GABA(A) receptors. Bicuculline application produced a greater decrease of the recovery cycle of these neurons at i40 degrees than at c40 degrees. As a result, the azimuth-dependent recovery cycle of these neurons was abolished or greatly reduced. Possible mechanisms underlying these observations and biological relevance to bat echolocation are discussed. 相似文献
1000.
Experimental and MRI evidence suggest that glatiramer acetate's (Copaxone) therapeutic effect in multiple sclerosis (MS) could be mediated by anti-inflammatory GA-reactive Th2 cells that enter the brain, cross-react with myelin antigens, and produce bystander suppression. Furthermore, a neuroprotective effect, possibly mediated by neurotrophic factors such as BDNF, has been suggested based on experimental evidence in animal models, and the observation that inflammatory cells can elaborate BDNF. Therefore, we examined BDNF production in 73 GA, 13 MBP, and 22 TT-reactive short-term T-cell lines from 12 MS patients treated with GA. Ten of 73 GA-TCL (14%), 1 of the MBP-TCL (3%), and 2 of the TT-TCL (9%) produced BDNF levels two standard deviations above the mean levels produced by resting TCL. RT-PCR analysis confirmed BDNF expression in some GA- and MBP-reactive TCL. The mean BDNF level produced by GA-TCL was significantly higher than that for MBP-TCL, or TT-TCL when lines originating from the same patients were compared (P=0.033). All 10 high BDNF-producing GA-reactive TCL were Th2-biased as determined by the IL-5/IFN-gamma levels ratio. A positive correlation was observed between BDNF and IL-5 (Th2 indicator) (P=0.006) but not with IFN-gamma Th1 indicator) levels in GA-TCL derived from MS patients during but not pre-treatment. We conclude that while BDNF production by T cells is not antigen-specific, GA-reactive TCL are more likely to produce BDNF, and to be Th2-biased. 相似文献