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51.
Angus M. McLean Elizabeth Babcock-Atkinson Kathleen Rein Donald A. Ruggirello Mario A. Gonzalez Patrick K. Noonan 《Pharmaceutical research》1987,4(4):327-331
Gallopamil is a calcium-channel antagonist with reported activity in experimental animals three to five times higher than that of verapamil. An automated high-performance liquid chromatographic (HPLC) method with fluorescence detection is described for the simultaneous determination of gallopamil and its metabolite norgallopamil in plasma. Gallopamil was well resolved from norgallopamil and other metabolites, allowing simultaneous quantitation of both drugs. The detection limit for both gallopamil and norgallopamil was 0.9 ng/ml. This method has been successfully used for the determination of gallopamil and norgallopamil following the administration of 25-, 37.5-, and 50-mg oral doses of drug. 相似文献
52.
Suppiah Balachandran Stuart Eason Lynn McGuire Suzanne Bernard Charles Boyd 《European journal of nuclear medicine and molecular imaging》1986,12(2):69-71
Summary In order to measure ejection fractions (EFs) from nuclear ventriculograms, we devised a semi-automated edge-detection technique based on a combination of inverse Fourier analysis and second-derivative techniques. Initial clinical studies showed that, for the left ventricle, our method gives EF values statistically identical with those obtained using a conventional isocontour technique. For the right ventricle, however, the values obtained using the two methods were somewhat more at variance. Despite requiring a longer processing time, the results obtained with our method are reproducible because less operator intervention is necessary. 相似文献
53.
Hemophilia A: genetic prediction and linkage studies in all available families in Finland 总被引:1,自引:0,他引:1
Anna-Elina Lehesjoki Pertti Sistonen Vesa Rasi Albert de la Chapelle 《Clinical genetics》1991,39(3):199-209
RFLP studies were done in 82 (75%) of all known hemophilia A families in the Finnish population (approximately 5 million). Two intragenic RFLPs (Bc1I/F8A, XbaI/p482.6) and two extragenic markers (TaqI/St14, Bg1II/DX13) were used. Among 263 females at risk, carriership could be evaluated with an intragenic marker in 47% and with an extragenic marker in 26%. In 27% of the females, carriership could be neither excluded nor confirmed; 68% of these females were relatives of an isolated patient. Eight recombinations between the factor VIII gene (F8C) and DXS52 (lod 25.02 at theta max 0.06), eight recombinations between F8C and DXS15 (lod 21.91 at theta max 0.05), and two recombinations between DXS52 and DXS15 (lod 33.56 at theta max 0.01) were found. Using multipoint linkage analysis, the most likely order of loci supported by the data was: F8C-DXS15-DXS52-DXS134. RFLP segregation analysis provides a highly useful method of carrier detection and prenatal diagnosis of hemophilia A, but its limitations must be carefully taken into account. 相似文献
54.
目的:研究枸杞地黄汤对老年小鼠学习记忆、自由基及免疫系统的影响。方法:采用水迷宫行为实验检测枸杞地黄汤对老年小鼠学习记忆的影响,通过测定皮层、海马中MDA和SOD水平检测药物对老年小鼠自由基系统异常改变的影响,通过测定老年小鼠免疫器官指数变化检测药物对老年免疫系统异常改变的影响。结果:5、10、20g/kg的枸杞地黄汤不同程度减小老年小鼠学习记忆障碍,降低皮层、海马中MDA水平,增加SOD活性,提高胸腺、脾指数。结论:枸杞地黄汤能够改善老年小鼠学习记忆障碍.调节不正常自由基系统和免疫系统。 相似文献
55.
Carolien J. Bouma Wiro J. Niessen Karel J. Zuiderveld Elma J. Gussenhoven Max A. Viergever 《Medical image analysis》1997,1(4):363-377
One prerequisite for standard clinical use of intravascular ultrasound imaging is rapid evaluation of the data. The main quantities to be extracted from the data are the size and the shape of the lumen. Until now, no accurate, robust and reproducible method to obtain the lumen boundaries from intravascular ultrasound images has been described. In this study, 21 different (semi-)automated binary-segmentation methods for determining the lumen are compared with manual segmentation to find an alternative for the laborious and subjective procedure of manual editing. After a preprocessing step in which the catheter area is filled with lumen-like grey values, all approaches consist of two steps: (i) smoothing the images with different filtering methods and (ii) extracting the lumen by an object definition method. The combination of different filtering methods and object definition methods results in a total of 21 methods and 80 experiments. The results are compared with a reference image, obtained from manual editing, by use of four different quality parameters—two based on squared distances and two based on Mahalanobis distances. The evaluation has been carried out on 15 images, of which seven are obtained before balloon dilation and eight after balloon dilation. While for the post-dilation images no definite conclusions can be drawn, an automated contour model applied to images smoothed with a large kernel appears to be a good alternative to manual contouring. For pre-dilation images a fully automated active contour model, initialized by thresholding, preceded by filtering with a small-scale median filter is the best alternative for manual delineation. The results of this method are even better than manual segmentation, i.e. they are consistently closer to the reference image than the average distance of all individual manual segmentations. 相似文献
56.
赵崇侃 《北京生物医学工程》1997,(1)
作者介绍了一种动态心率检测电路,它能准确、可靠地检出在运动状态下的人体心率。电路采用两种检测技术,一种为双时值QRS波检测法,另一种为光电脉搏检测法。 相似文献
57.
The present paper reports 11 cases of light chain disease (LCD) sequently found in several citles over Fujian province, Immunological classification of this group of LCD ww as follows: six of me cases belonged to type λ, four of them were type κ, and another one was a double LCD. We found that LCD was common in Fujlan only next to multiple myeloma (MM) of IgG class and accounted for 20% of the total 55 MM cases found in recent yean.It to well known that In matt patients of LCD M protein or Bence Jones proteinemia (BJPemia) to not detectable by conventional electro-phoresis. Our studies show that by making serum protein along with urinary BJP electrophoresis on the same one gel plate the sltuation can be greatly Improved It not only favour* the recognition of smail and faint band or bands of free light chain in serum, but also provides a repid and sensitive way, i. e. , immunofixation, to directly detect urinary light chain on the gel plate Immediately after electrophresis has been run. 相似文献
58.
We study in this paper the resolution by single shooting of an optimal control problem with a bang‐bang control involving a large number of commutations. We focus on the handling of these commutations regarding the precise computation of the shooting function and its Jacobian. We first observe the impact of a switching detection algorithm on the shooting method results. Then, we study the computation of the Jacobian of the shooting function, by comparing classical finite differences to a formulation using the variational equations. We consider as an application a low thrust orbital transfer with payload maximization. This kind of problem presents a discontinuous optimal control, and involves up to 1800 commutations for the lowest thrust. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
59.
Conditions under which amphetamine may facilitate stimulus detection task choice performance in rats were investigated. Rats
(n=15) were trained in a two-choice, light-detection task to three successively more stringent criterion levels of task training
(minimal, intermediate, and extended) and then tested after administration of saline, 0.25, 0.50, and 0.75 mg/kg d-amphetamine (AMP). For each training level, baseline levels of choice accuracy were maintained at approximately 82% by manipulating
the animals’ cue duration. No aspect of performance was enhanced by any dose of AMP after minimal criteria training, and there
was a dose-dependent decrease in the number of trials completed. After the intermediate level of training, the 0.25 mg/kg
dose of AMP reliably increased choice accuracy, there was no reliable change in choice reaction time, and there was a dose-dependent
decrease in the number of trials completed. After the extended training, the 0.25 mg/kg dose of AMP reliably increased choice
response accuracy, the 0.25 and 0.50 mg/kg doses of AMP reliably decreased choice reaction time, and there was no reliable
change in the number of trials completed at any dose of AMP. These results support the contention that psychostimulants can
facilitate the choice performance of rats in stimulus detection tasks if an appropriately low dose is used and the animal’s
behavior is strongly controlled by the stimulus-reinforcement contingencies of the task.
Received: 24 September 1997 / Final version: 9 May 1998 相似文献
60.
选择46例晚期肺癌患者应用LAK/IL-2疗法观察患者近期临床改善情况及治疗前后其免疫指标的变化情况。选择胎儿胸腺淋巴组织作前体细胞,体外用重组IL-2诱导制备LAK细胞,每输3次LAK细胞为1疗程,每次输入细胞数为05×109,化疗以采用丝裂霉素、长春新碱、顺铂或卡铂、鬼臼乙叉甙为主的方案,治疗结果:本组患者治疗有效率(CR+PR)达70%,同时患者免疫指标好转。本研究提示LAK/IL-2联合疗法临床近期疗效较满意,同时可显著改善机体免疫功能,是晚期肺癌患者一种可行的有效方法 相似文献