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71.
Fast T(1) mapping techniques are a valuable means of quantitatively assessing the distribution and dynamics of intravenously or orally applied paramagnetic contrast agents (CAs) by noninvasive imaging. In this study a fast T(1) mapping technique based on the variable flip angle (VFA) approach was optimized for accurate T(1) quantification in abdominal contrast-enhanced (CE) MRI. Optimization methods were developed to maximize the signal-to-noise ratio (SNR) and ensure effective RF and gradient spoiling, as well as a steady state, for a defined T(1) range of 100-800 ms and a limited acquisition time. We corrected B(1) field inhomogeneities by performing an additional measurement using an optimized fast B(1) mapping technique. High-precision in vitro and abdominal in vivo T(1) maps were successfully generated at a voxel size of 2.8 x 2.8 x 15 mm(3) and a temporal resolution of 2.3 s per T(1) map on 1.5T and 3T MRI systems. The application of the proposed fast T(1) mapping technique in abdominal CE-MRI enables noninvasive quantification of abdominal tissue perfusion and vascular permeability, and offers the possibility of quantitatively assessing dilution, distribution, and mixing processes of labeled solutions or drugs in the gastrointestinal tract.  相似文献   
72.
Prof. Dr.  O. P. Steeno 《Andrologia》1989,21(2):103-112
Summary: For the quantitative determination of the testicular size or volume, two groups of apparatus are available: on the one hand, model testes, which are extremely valuable in longitudinal and cross-sectional studies during the period of pubescence, and on the other hand, measuring devices, with which the testicular dimensions can be specified. The latter instruments are helpful chiefly during the adolescent years and the diagnosis of problems surrounding fertility. The testicular volume can be calculated subsequently from the specific testicular measurements. The formula, for computing the volume of an ellipsoid, seems to be the most suitable for this purpose. Appliances also have been developed, which allow the largest (longitudinal) dimension (in mm) and the testicular volume (in cm3) to be read off simultaneously. A tonometer can be useful to quantitatively estimate the testicular consistency, which is a parameter of the testicular integrity at the level of tubular function (spermatozoa production).  相似文献   
73.
本文简单介绍冷冻断裂复型电镜技术在国内、外的概况,並阐明了该项新技术的独特作用和具体的操作步骤;在制作生物样品时所需的仪器设备和试剂的配制等内容。  相似文献   
74.
Currently few subjective measures of Quality of Life (QoL) are available for use in developing countries, which limits their theoretical, methodological, and practical contribution (for example, exploring the relationship between economic development and QoL, and ensuring effective and equitable service provision). One reason for this is the difficulty of ensuring that translated measures preserve conceptual, item, semantic, operational, measurement; and functional equivalence (Herdman, M., Fox-Rushby, J., & Badia, X. (1998). Quality of Life Research, 7, 331), which is illustrated by an account of the translation, pre-piloting, and administration of a new individualised QoL measure, the Global Person Generated Index or 'GPGI'. The GPGI is based on the widely used Patient Generated Index (Ruta, Camfield, & Martin, (2004) Quality of Life Research, 13, 1545.) and offers many of the advantages of the participatory approaches commonly used in developing countries, with added methodological rigour, and quantitative outcomes. It was successfully validated in Bangladesh, Thailand, and Ethiopia, using quantitative and qualitative methods--open-ended, semi-structured interviews (SSIs), conducted immediately post-administration. Both the measure and method of 'qualitative validation' described later in the paper offer an exciting alternative for future researchers and practitioners in this field. The quantitative results suggest the GPGI shows cultural sensitivity, and is able to capture both the areas that are important to respondents, and aspects of life one would expect to impact on QoL in developing countries. There were strong correlation between scores from the GPGI and SSIs for the area of health, and moderate correlations for 'material wellbeing' (MWB)('Material wellbeing' refers to respondents' perceptions of their achievement in the areas of farming, debt reduction, assets, crops, livestock, job, land, property, and agriculture) and children. Weak to moderate correlations were observed between the Satisfaction with Life Scale and the GPGI; however, the highest coefficient was between the GPGI and the most conceptually similar item. Statistically significant differences were seen in GPGI scores between rich and poor, urban and rural respondents, and different countries. Health and material wellbeing scores, derived from the SSIs, also showed a linear relationship with GPGI scores, with a suggestion of curvilinearity at the higher levels, as predicted by a general QoL causal model. In conclusion, the GPGI has great potential for use in this area, especially when supported by extensive interviewer training, and supplemented with a cognitive appraisal schedule.  相似文献   
75.

Aim of the study

Cree traditional medicine is commonly used concomitantly with prescribed drugs to treat health problems related to type II diabetes (T2D) that is endemic in the Cree population. However, the safety of traditional Cree medicines with respect to drug metabolism is unknown.

Materials and methods

Seventeen anti-diabetic plant extracts were screened for their potential inhibition of 11 isoforms of the drug-metabolizing cytochrome P450s (CYPs), and flavin-containing monooxygenase 3 (FMO3) in fluorometric plate reader assays. Comparative analyses were conducted to determine if particular extracts were more inhibitory, or if particular enzymes were more inhibited.

Results

Many anti-diabetic plant extracts inhibited the CYPs, with CYP2C and 3A isoforms being most prone to inhibition. The order of inhibition for the enzymes by the Cree plant extracts was: 2C19 > 3A7 > 3A5 > 3A4 > 2C9 > 2C8 > FMO3 > 1A2 > 2E1 > 19 > 2D6 > 2B6. Extracts from Rhododendron groenlandicum, Sorbus decora, and Kalmia angustifolia were identified as having strong inhibition towards many CYP isoforms.

Conclusion

These findings demonstrate that extracts from most plant species examined have the potential to affect CYP2C- and 3A4-mediated metabolism, and have the potential to affect the bioavailability and pharmacokinetics of conventional and traditional medicines during concomitant use.  相似文献   
76.
This article, based on a report prepared for the International Council of Ophthalmology (ICO) and the International Society for Low Vision Research and Rehabilitation (ISLRR), explores the assessment of various aspects of visual functioning as needed to document the outcomes of vision rehabilitation. Documenting patient abilities and functional vision (how the person functions) is distinct from the measurement of visual functions (how the eye functions) and also from the assessment of quality of life. All three areas are important, but their assessment should not be mixed. Observation of task performance offers the most objective measure of functional vision, but it is time‐consuming and not feasible for many tasks. Where possible, timing and error rates provide an easy score. Patient response questionnaires provide an alternative. They may save time and can cover a wider area, but the responses are subjective and proper scoring presents problems. Simple Likert scoring still predominates but Rasch analysis, needed to provide better result scales, is gaining ground. Selection of questions is another problem. If the range of difficulties does not match the range of patient abilities, and if the difficulties are not distributed evenly, the results are not optimal. This may be an argument to use different outcome questions for different conditions. Generic questionnaires are appropriate for the assessment of generic quality of life, but not for specific rehabilitation outcomes. Different questionnaires are also needed for screening, intake and outcomes. Intake questions must be relevant to actual needs to allow prioritization of rehabilitation goals; the activity inventory presents a prototype. Outcome questions should be targeted at predefined rehabilitation goals. The Appendix cites some promising examples. The Low Vision Intervention Trial (LOVIT) is an example of a properly designed randomized control study, and has demonstrated the remarkable effectiveness of vision rehabilitation. It is hoped that further similar studies will follow.  相似文献   
77.
后入路手术治疗胸腰段爆裂性骨折   总被引:1,自引:1,他引:0  
目的分析后入路手术治疗胸腰段爆裂性骨折的疗效及适应证。方法应用后入路手术治疗胸腰段爆裂性骨折38例。从影像学、手术操作过程及神经功能恢复等方面分析疗效。结果伤椎高度由47·3%恢复到94·4%;水平移位完全恢复;Cobb角由术前22·6°恢复到术后3·6°。椎管受压程度:删除椎管开放减压的7例,余受压面积由术前42%恢复到术后16%,受压的矢状径从术前54·9%恢复到81·8%。脊髓神经功能恢复依照Frankel分级标准均有1级以上改善。结论合理选择后入路手术对胸腰段爆裂性骨折治疗效果良好,手术中进行椎管造影有助于提高复位效果。  相似文献   
78.
C型骨盆骨折合并髋关节中心性脱位的手术治疗   总被引:1,自引:1,他引:0       下载免费PDF全文
万仑  吕波  刘仲前 《中国骨伤》2006,19(6):348-350
目的:研究C型骨盆骨折合并髋关节中心性脱位的临床疗效。方法:13例患者中男8例,女5例;年龄23~65岁,平均36.5岁。骨盆骨折分型:C1型8例,C2型3例,C3型2例。髋臼“T”形骨折2例,粉碎性骨折9例,双柱骨折2例。均采用手术治疗,术前术后均采用股骨髁上牵引,术中采用髂腹股沟入路,必要时附加患髋后外侧切口,术中采用重建钢板固定。结果:本组随访时间6~28个月,平均13.4个月。髋臼骨折复位后残存移位:0~1mm9例,2~3mm2例,4~5mm2例,无>5mm者。髂骨骨折复位后各向残存移位:0~1mm9例,2~5mm3例,>5mm1例。3例原发性坐骨神经损伤的患者,术后3个月内其感觉、运动功能全部获得恢复。1例继发性坐骨神经损伤,术后6个月恢复。异位骨化2例,股骨头坏死、髋臼及股骨头软骨坏死、髋关节创伤性关节炎5例,患者关节疼痛、活动受限,影响功能。疗效综合评定:优8例,良1例,可2例,差2例。结论:C型骨盆骨折合并髋关节中心性脱位通过手术治疗,能够最大程度恢复其解剖结构,术后关节功能恢复较好。  相似文献   
79.
目的比较聚合酶链反应-序列特异性引物(PCR-SSP)进行HLA-Ⅰ类A、B抗原位点分型的准确性,并探讨血清学分型错误发生的原因。方法用PCR-SSP以及单克隆抗体血清学分型技术对HLA-A、B分型并比较。结果34例样本PCR-SSP基因分型无假阳性和假阴性出现。PCR-SSP法与血清学比较,血清学检出错误或漏检率分别为HLA-A位点23.5%,B位点26.5%。血清学发生错误或易混淆的抗原有:A2和A68、A32和A33,B5、B60和61。结论PCR-SSP法进行HLA-A、B抗原等位基因分型具有分辨率高、特异性强、重复性好、实验过程简捷快速、分型结果较血清学更加准确可靠的优点。  相似文献   
80.
目的通过回顾性调查,探讨北海市白血病发病情况. 方法按FAB白血病诊断与分型标准.结果从18年在该院就诊和住院的患者6306435人次中,初发并确诊的各类白血病158例,发病率2.5/105与1988年全国调查的各类白血病发病率2.62/105相近;各类白血病的构成比、性别、年龄以及各类白血病亚型分布等结果分析与全国、上海市等区域的调查分析结果也很近似.结论该文样本量很大,可基本反映北海市白血病发病率的概况.  相似文献   
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