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61.
目的 建立一种肱骨近端骨密度(BMD)的测量方法,研究肱骨近端BMD与年龄和体质量指数(BMI)的关系,探讨肱骨近端BMD在预报骨质疏松症的敏感性.方法 选择绝经后健康女性志愿者,使用Hologie DELPHI-A双能X射线骨密度仪及本研究设计的肩部定位器和前臂定位器测虽肱骨近端BMD.研究第一部分包括30名忐愿者,每人连续测量右侧肱骨近端BMD 2次,根据测量结果计算短期精密度RMS SD和RMS CV;第二部分包括92名志愿者,记录其年龄、身高、体重,测量右侧肱骨近端BMD,分析肱骨近端BMD与年龄和BMl的相关性.结果 本研究肱骨近端BMD测量方法的短期精密度:RMS SD=0.011 g/cm2,RMS CV=2.4%.本研究92名志愿者平均(60.2±6.4)岁,平均身高(159.5±5.4)cm,平均体质晕(59.4±7.5)kg,平均BMI 23.3±2.7,平均肱骨近端BMD(0.543±0.083)g/cm2,肱骨近端BMD 同年龄呈负相关,同BMI无显著相关.结论 本研究建立了一种测苗肱骨近端BMD的方法;年龄越人肱骨近端BMD越低;由于BMI对BMD的影响会掩盖骨质的丢失,而非负重区域即肱骨近端会最大程度地减少BMI对BMD的影响程度. 相似文献
62.
MONIQUE DAVRIL MIREILLE GUAY KIA-KI HAN FRANCOIS LAMY 《Chemical biology & drug design》1987,29(1):68-77
This report describes the use of photolysis and ozonolysis as a means of achieving complete cleavage of the pyridinium ring of (iso)desmosine in crosslinked elastin peptides. Although photolysis leads to the opening of the ring with concomitant formation of lysine, the peptide chains remain attached. Subsequent ozonolysis is able to completely achieve the cleavage of the rest of the ring skeleton, thus leading to the separation of the peptide chains. Formation of new amino acids, i.e. α-aminoadipic and glutamic acids, is emphasized. Localization of these amino acids within the released peptides should be of help in structural investigations on the crosslinking zones involving either isodesmosine or desmosine. However, other amino acids such as tyrosine and phenylalanine are sensitive to this procedure and side reactions occur which are responsible for peptide bond cleavage with the formation of breakdown products. 相似文献
63.
Chrisa Nitsiou 《Early child development and care》2006,176(8):817-833
As our world becomes increasingly multicultural in nature, multilingual skills constitute an everyday phenomenon in schools. Since most of the second-language research has focused on school-age students, more research had to be conducted with language-minority students at the kindergarten level in order for psychologists and educators to develop effective and efficient systems for evaluating and tracking the developmental status of young language-minority children. The purpose of this study was to investigate the potential usefulness of a standardized continuous progress measure, the Picture Naming Individual Growth and Development Indicator, to longitudinally assess language development in 23 language-minority children, as well as in 13 native English-speaking children. Results indicated that we could use the Picture Naming Individual Growth and Development Indicator to detect differences in first-language and second-language development in language-minority children, as well as to detect differences between the two groups of children in their expressive English-language skills. 相似文献
64.
通过具体的实验数据,讨论在药代动力学实验中如何加入曲线下面积(AUC)的计算,以帮助学生理解并掌握这一概念;在实验室设置不同剂量组,给药后比较剂量与浓度是否呈等比例关系,以此加深学生对于一级动力学消除及其临床意义的理解。 相似文献
65.
Introduction and Aims. Different self‐report methods tend to produce different estimates of alcohol consumption. The present study compares differences in rates and risk levels based on responses to a modified version of the Daily Drinking Questionnaire (m‐DDQ) and quantity‐frequency (QF) questions. Design and Methods. The sample comprised 2082 university students, 61% of whom were female and 39% male with a mean age of 23.5 years. An email containing an online link to a brief six‐question survey was emailed to students enrolled in participating faculties at the University of Wollongong, Australia. Current drinkers completed m‐DDQ and QF questions about alcohol consumption. Results. QF methods identified significantly lower estimates of consumption (Mean = 9.15, SD = 12.51) compared with m‐DDQ (Mean = 13.06, SD = 14.07). Allocation to risk categories based on the Australian Alcohol Guidelines were conducted for both the m‐DDQ and QF methods. Almost twice as many students were found to be drinking at levels considered risky using the m‐DDQ method compared with QF. In addition, the relative rank order of participants varied significantly between the two methods. Discussion and Conclusions. The m‐DDQ method identified higher rates of drinking and categorised almost twice as many individuals into risky categories of drinking compared with QF. Such variations have major implications for identification of risk groups in health promotion or prevention programs.[Utpala‐Kumar R, Deane FP. Rates of alcohol consumption and risk status among Australian university students vary by assessment questions. Drug Alcohol Rev 2009] 相似文献
66.
Further evidence of dopamine transporter dysregulation in ADHD: a controlled PET imaging study using altropane. 总被引:4,自引:0,他引:4
Thomas J Spencer Joseph Biederman Bertha K Madras Darin D Dougherty Ali A Bonab Elijahu Livni Peter C Meltzer Jessica Martin Scott Rauch Alan J Fischman 《Neuropsychopharmacology》2007,62(9):1059-1061
BACKGROUND: The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however. METHOD: Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-na?ve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD. RESULTS: Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder. CONCLUSIONS: These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD. 相似文献
67.
1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence. 相似文献
68.
69.
70.
P. Neary C. Hurson D. O. Briain A. Brabazon D. Mehigan T. V. Keaveny S. Sheehan 《Colorectal disease》2007,9(2):166-172
OBJECTIVE: Colonic infarction is a recognized complication of abdominal aortic aneurysm (AAA) surgery. The clinical difficulty in establishing the diagnosis combined with the patient's poor physiological status is usually associated with a fatal outcome. We assessed our experience with this problem to identify a possible risk factor profile for these patients. METHOD: Patients records were identified from the operative logs, intensive care unit, Hospital Inpatient Enquiry system and vascular unit databases over a 6-year period. RESULTS: A total of 405 patients underwent AAA repair during this period; 140 as emergency ruptures. Nine patients were identified from the databases with known colonic infarction (2.2%). One was a woman. The mean age was 70 years. Seven patients had emergency ruptures (5%). Twenty independent risk factors were analysed using univariate and multivariate logistic regression models. Significant risk factors identified by using a multivariate analysis included the nature of the presenting patient, preoperative hypotension, prolonged cross-clamp time, intra-operative ischaemia and postoperative acidosis. Confirmatory diagnosis was made by colonoscopy in eight patients. One patient survived following the salvage surgery. The mean duration of survival was 10.5 days. The overall mortality was 89% of patients. CONCLUSION: In our unit infrarenal AAA repair has a 2.2% rate of colonic infarction. A definitive diagnosis is best made by colonoscopy. A risk factor profile for the development of colonic infarction may be constructed on the basis of specific clinical parameters. Earlier intervention on the basis of this profile may ultimately reduce the current excessive mortality. 相似文献