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81.
本文提出了差示一线性组合导数光谱法用于测定混合组分体系的基本原理和实验方法。并试用本法消除了扑尔敏、溴化丙胺太林、灵芝粉及附加剂之间的相互干扰,从而分别测定了扑咳灵片巾扑尔敏和溴化丙胺太林的含量,其平均回收率分别为100.2±1.49%(CV)和99.89±1.03%(CV)。其精密度、准确度均好。  相似文献   
82.
Quantitative coronary arteriography: design and validation   总被引:1,自引:0,他引:1  
Ratib  OM; Mankovich  NJ 《Radiology》1988,167(3):743-747
The authors assessed the performance of an automatic and rapid coronary quantification method by evaluating its accuracy in a stenosis phantom. Measurements were obtained with a lucite phantom with 2-, 3-, and 4-mm vessel diameters and concentric stenoses of 33%, 50%, 67%, and 75%. Direct digital angiographic images as well as 10 X 10 spot films and 35-mm cine angiography films were acquired with and without structural noise and mask subtraction. The films were digitized with magnification factors of one and two. An interactive analysis program was used to automatically determine the vessel edges with a Gaussian fit to the cross-sectional density profiles perpendicular to the center line of the vessel. Relative changes of the densitometric cross-sectional area along the vessel were used to assess the percentage of stenosis. Densitometric measurements were comparable in both digital and cine angiograms (r = .99 and r = .98, respectively); however, diameter measurements showed a higher variability and were dependent on the amount of magnification applied to the images.  相似文献   
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This study investigated the leptin response to vigorous exercise. We examined 12 sedentary subjects (7 males and 5 females) aged 45-59 yr (53 +/- 6.3) with body mass index of 26.1 +/- 8 Kg/m2. The selection of the population was based on the absence of endocrine or any other pathological anomaly. Basal concentrations of leptin, cortisol, insulin and glucose were measured at 08:00 h after an overnight fast. After that the individuals were placed on a computer-controlled ergometer performing a 20-min run at 70% VO2 max under controlled environmental conditions. Blood samples were obtained immediately after the completion of the test. For the following hour, all subjects were placed in the supine position and blood samples were taken at the end of the time period. Statistical evaluation was performed using analysis of variance (ANOVA) for independent variables. Plasma leptin levels exhibited a statistically significant decrease at the end of the 20 min running period (1.5 +/- 0.1 ng/ml vs 3.2 +/- 0.4 ng/ml, p<0.005). Interestingly, after 1 h in the supine position, leptin levels reached the basal values (3.17 +/- 0.1 ng/ml). The concentration of insulin, glucose and cortisol were unaltered during the exercise test (9.8 +/- 1.3 vs 8.85 +/- 1.27 microIU/ml, 95.58 +/- 6.71 mg/dl vs 98.4 +/- 0.78 mg/dl and 10.35 +/- 0.74 microg/dl vs 9.5 +/- 0.7 microg/dl respectively). In conclusion, our data demonstrate a relationship between stressful physical activity and plasma leptin levels in middle-aged subjects.  相似文献   
85.
We localised amino acids in the mid‐peripheral aged human retina and a retina that had undergone radiation treatment 10 years earlier. The distribution pattern of glutamate, γ‐amino butyric acid (GABA), glycine, glutamine and taurine, reflected patterns established in the primate retina. The retina that had undergone radiation exposure displayed both anatomical and neurochemical remodelling. The proximal retina comprised around 40 to 45 per cent of the total retina and neuronal kinesis and aberrant neuronal projections were also present. Amino acid neurochemistry was strikingly different with Müller cells displaying GABA loading, glycinergic neurons displaced and displaying a very high level of glycine labelling. We conclude that radiation exposure triggered these changes in the human retina and likely reflects general remodelling of structure and function following ischaemic damage to endothelial cells.  相似文献   
86.

Background and purpose:

This study establishes a pharmacokinetic/pharmacodynamic (PK/PD) model to describe the time course and in vivo mechanisms of action of the antinociceptive effects of lumiracoxib, evaluated by the thermal hyperalgesia test in rats.

Experimental approach:

Female Wistar fasted rats were injected s.c. with saline or carrageenan in the right hind paw, followed by either 0, 1, 3, 10 or 30 mg·kg−1 of oral lumiracoxib at the time of carrageenan injection (experiment I), or 0, 10 or 30 mg·kg−1 oral lumiracoxib at 4 h after carrageenan injection (experiment II). Antihyperalgesic responses were measured as latency time (LT) to a thermal stimulus. PK/PD modelling of the antinociceptive response was performed using the population approach with NONMEM VI.

Results:

A two-compartment model described the plasma disposition. A first-order model, including lag time and decreased relative bioavailability as a function of the dose, described the absorption process. The response model was: LT=LT0/(1 +MED). LT0 is the baseline response, and MED represents the level of inflammatory mediators. The time course of MED was assumed to be equivalent to the predicted profile of COX-2 activity and was modelled according to an indirect response model with a time variant synthesis rate. Drug effects were described as a reversible inhibition of the COX-2 activity. The in vivo estimate of the dissociation equilibrium constant of the COX-2-lumiracoxib complex was 0.24 µg·mL−1.

Conclusions:

The model developed appropriately described the time course of pharmacological responses to lumiracoxib, in terms of its mechanism of action and pharmacokinetics.  相似文献   
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输液中注射用头孢米诺钠的稳定性   总被引:9,自引:0,他引:9  
蒋云根  朱宁江  付庆华  谢文 《医学争鸣》2005,26(11):971-971
1材料和方法 1.1材料日本岛津10-Arp高效液相色谱仪,C18柱(5 μm,4.6 mm×150 mm),PHS-3C型pH计(上海雷磁仪器厂);注射用头孢米诺钠(南昌立健药业有限公司,批号:20040701),50 g/L葡萄糖注射液(四川科伦大制药有限公司,批号:040912-091),100 g/L葡萄糖注射液(湖南科伦大制药有限公司,批号:040710-07),9 g/L氯化钠注射液(湖南科伦大制药有限公司,批号:040926-06),葡萄糖氯化钠注射液(湖南科伦大制药有限公司,批号:040929-06),甲硝唑注射液(安徽双鹤药业有限公司,批号:040926-2E);甲醇、冰醋酸、四氢呋喃均为分析纯.  相似文献   
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