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1.
个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
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Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
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碱离子水饮用后血小板聚集率的的变化(附30例报告)   总被引:1,自引:0,他引:1  
目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2~3月,>3~6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max%)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80%)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。  相似文献   
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The goal of this study was to develop an understanding the developmental trajectory of smoking behaviors in adolescents who seek smoking cessation treatment to inform tailored prevention and treatment efforts; this includes identifying gender differences in smoking behaviors. Smoking trajectory was examined retrospectively in 639 treatment-seeking adolescents (59% female; 44% African American, 50% European American, mean ± SD daily cigarettes per day [CPD] 19.16 ± 7.2 for both girls and boys). Smoking trajectory variables examined included age at first cigarette, age at daily smoking (a proxy measure for onset of dependence), and age at treatment request. The time interval from first cigarette to daily smoking was shorter for girls than for boys (mean ± SD 0.9 ± 1.1 years for girls, 1.3 ± 1.5 years for boys, p < 0.01). From this clinical sample of adolescent smokers, findings suggest only a brief window of opportunity for secondary preventive interventions before the development of tobacco dependence. Additional research is needed to explore the specific factors that differentially affect smoking trajectory in girls compared to boys.  相似文献   
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We previously showed that chronic cocaine use by active illicit users produced a longer plasma half-life than expected based on acute low-dose cocaine studies. Here we report urinary excretion patterns of cocaine metabolites as benzoylecgonine (BE) equivalents from 18 of the same individuals, housed for up to 14 days on a closed research unit. In addition, we evaluated whether creatinine normalization of BE equivalents increased mean detection time and reduced mean within-subject variability. All urine voids (N = 953) were individually assayed; BE equivalents were determined semi-quantitatively by FPIA. Compared to concentration in first void after admission, BE equivalents decreased to approximately 33%, 8%, and 4% at 24, 48, and 72 h, respectively. Mean +/- SD (range) time to first negative specimen (BE equivalents < 300 ng/mL) was 43.6 +/- 17.1 (16-66) h. BE equivalents fluctuated considerably across successive specimens; 69% of participants tested positive at least once after testing negative, and the mean time to last positive specimen was 57.5 +/- 31.6 (11-147) h after the first specimen. Thus, mean cocaine metabolite detection times were consistent with prolonged elimination, with 63% of participants testing positive longer than the expected 48-h window of detection after admission to the unit. Mean time to last positive after last use of cocaine, known by self-report only, was approximately 81 +/- 34 (34-162) h. Creatinine normalization, with the cut-off of 300 ng BE equivalents/mg creatinine, increased detection time: mean time to first negative specimen was 54.8 +/- 20.7 (20-100) h, and mean time to last positive specimen was 88.4 +/- 51.0 (35.6-235) h. Compared with the concentration in the first void after admission, BE equivalents/creatinine decreased to approximately 56%, 6%, and 5% at 24, 48, and 72 h. However, creatinine normalization did not reduce the fluctuation of BE equivalents across successive specimens. Thus, creatinine normalized values may be useful when the goal is to maximize the probability or duration of cocaine metabolite detection, but may be less useful in determining whether an individual has used cocaine since a previous specimen collection.  相似文献   
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Objective : Acute abdominal pain is a common problem in childhood, and appendicitis is frequently diagnosed by general practitioners and doctors working in emergency departments. The objective of the present report was to determine the frequency of appendicitis in a group of children with acute abdominal pain presenting to the emergency department of a general hospital, as well as attempting to analyse the manner in which these patients were managed.
Methodology : The initial assessment in hospital (by resident hospital staff) of the study group of patients was analysed and their subsequent clinical progress documented.
Results : The present report shows that the vast majority of children with acute abdominal pain do not have appendicitis and that appendicitis is significantly over-diagnosed by junior hospital doctors.
Conclusions : Appendicitis is a clinical diagnosis, best made by an experienced member of the paediatric surgical team. Frequent review, with a minimum of investigations, provides the best means of making a rational decision regarding surgery.  相似文献   
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BACKGROUND: Sweat testing is a noninvasive technique for monitoring drug exposure in treatment, criminal justice, and employment settings. METHODS: We evaluated cocaine excretion in 9 participants' sweat after they received 3 low doses (75 mg/70 kg) of cocaine HCl subcutaneously within 1 week and, 3 weeks later, 3 high doses (150 mg/70 kg). Six additional participants completed portions of the study. PharmChek sweat patches (n = 1390) were collected throughout a 3-week washout period, reflecting previously self-administered drugs, and during and after controlled dosing. RESULTS: Cocaine was the primary analyte detected with 24% of patches positive at the gas chromatography-mass spectrometry limit of quantification of 2.5 ng/patch and 7% of patches at the proposed Substance Abuse and Mental Health Services Administration cutoff of 25 ng/patch. Ecgonine methyl ester (EME) was detected more often and at generally higher concentrations than benzoylecgonine. In patches containing both metabolites, there was no statistically significant difference in the benzoylecgonine/EME ratio based on length of patch wear. During washout, 2 participants' weekly patches tested positive (> or =25 ng/patch) during the first week; one remained positive during week 2; and none were positive during week 3. Cocaine and EME were detectable within 2 h; benzoylecgonine was not detected until 4-8 h after low doses and slightly sooner after high doses. The majority of drug was excreted within 24 h. Over 70% of weekly patches worn during low doses were positive for cocaine (> or =25 ng/patch), increasing to 100% during high doses. CONCLUSION: Sweat testing is an effective and reliable method of monitoring cocaine exposure.  相似文献   
9.
Hair testing for the determination of drug exposure has many useful applications. Drug incorporated into hair can be found for extended periods following drug exposure. There are few controlled drug administration studies investigating drug distribution into human hair. Ten volunteers participated in a 10-week controlled cocaine and codeine administration study while residing in the secure research ward. Weekly hair samples were collected by electric razor. During the low-dose week (week 4), volunteers received 75 mg/70 kg cocaine subcutaneously and 60 mg/70 kg codeine orally on alternating days, a total of three doses for each drug. Similarly, during week 7, volunteers received three doses 150 mg/70 kg cocaine and 120 mg/70 kg codeine. Maximum hair concentrations (C(max)) were found 1 to 3 weeks after low and high doses. Dose-related C(max) values of cocaine, benzoylecgonine, ecgonine methyl ester, norcocaine, cocaethylene, and codeine were found following low and high doses. Hair analysis was performed using liquid chromatography tandem mass spectrometry. A positive linear relationship was found between total melanin content of hair and C(max) of codeine, cocaine, and metabolites following high dosing. This study demonstrated dose-related concentrations of cocaine and metabolites in human hair following controlled cocaine administration. These data are the first demonstrating melanin-related incorporation of cocaine and metabolites into human hair following controlled cocaine administration.  相似文献   
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