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Andrew M Briggs John D Wark Susan Kantor Rayson Teh Alison M Greig Nicola L Fazzalari Kim L Bennell 《Journal of clinical densitometry》2005,8(3):314-319
Analysis of apparent bone mineral density (BMD) in the lumbar spine is commonly based on anteroposterior (AP) scanning using dual-energy X-ray absorptiometry (DXA). Although not widely used, clinically important information can also be derived from lateral scanning. Vertebral bone density, and therefore strength, can may vary in different subregions of the vertebral body. Therefore, subregional BMD measurements might be informative about fracture risk. However, the intrarater and interrater precision of in vivo subregional BMD assessments from lateral DXA remains unknown. Ten normal, young (mean: 24 yr) and 10 older (mean: 63 yr) individuals with low BMD were scanned on one occasion using an AP/lateral sequence. Each lateral scan was reanalyzed six times at L2 by three raters to determine the intrarater and interrater precision in selecting seven regions of interest (subregions). Precision was expressed using percentage coefficients of variation (% CV) and intraclass correlation coefficients (ICC). Intrarater precision ranged from ICC(1,1) 0.971 to 0.996 (% CV: 0.50-3.68) for the young cohort and ICC(1,1) 0.934 to 0.993 (% CV: 1.46-5.30) for the older cohort. Interrater precision ranged from ICC(2,1) 0.804 to 0.915 (% CV: 1.11-2.35) for the young cohort and ICC(2,1) 0.912 to 0.984 (% CV: 1.85-4.32) for the older cohort. Scanning a subgroup of participants twice with repositioning was used to assess short-term in vivo precision. At L2, short-term in vivo precision ranged from ICC(1,1) 0.867 to 0.962 (% CV: 3.38-9.61), at L3 from ICC(1,1) 0.961 to 0.988 (% CV: 2.02-5.57) and using an L2/L3 combination from ICC(1,1) 0.942 to 0.980 (% CV: 2.04-4.61). This study demonstrated moderate to high precision for subregional analysis of apparent BMD in the lumbar spine using lateral DXA in vivo. 相似文献
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Barbara Porton Adriana Ferreira Lynn E DeLisi Hung Teh Kao 《Neuropsychopharmacology》2004,55(2):118-125
BACKGROUND: Synapsin III plays a role in neuronal plasticity and maps to chromosome 22q12-13, a region suggested to be linked to schizophrenia. To determine if synapsin III plays a role in this disease, we searched for polymorphisms in this gene in patients with schizophrenia and controls. METHODS: The synapsin III gene was initially sequenced from 10 individuals with schizophrenia to identify polymorphisms. Association analysis was then performed using 118 individuals with schizophrenia and 330 population controls. Synapsin III expression was studied by immunoblot analyses, and phosphorylation sites were mapped by sequencing trypsin-digested synapsin III fragments phosphorylated with phosphorus-32. RESULTS: A rare, missense polymorphism, S470N, was identified in the synapsin III gene and appeared more frequently in individuals with schizophrenia than in controls (p =.0048). The site affected by the polymorphism, Ser470, was determined to be a substrate for mitogen-activated protein kinase, a downstream effector of neurotrophin action. Phosphorylation at Ser470 was increased during neonatal development and in response to neurotrophin-3 in cultured hippocampal neurons. CONCLUSIONS: Our observations suggest an association of a rare polymorphism in synapsin III with schizophrenia, but further studies will be required to clarify its role in this disease. 相似文献
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Masaki Shinoda Tsuyoshi Yamaguchi Yoshimi Tanaka Osamu Sato Sin Kobayashi Yutaka Suzuki 《Child's nervous system》1992,8(4):219-221
Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by 123I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome. 相似文献
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背景:大多数已报道的基底细胞癌(BCCs)的特征主要是依据高加索患者。而关于亚洲人中不完全切除BCCs的特征少见报道。目的:本研究调查了新加坡亚洲居民的BCCs特征,并对常规外科切除术后完全切除与不完全切除肿瘤进行了比较。患者和方法:收集1991--1995年间在国家皮肤病中心行肿瘤切除术的原发性BCC患者的病历进行回顾性研究。结果:166例BCC患者(男女比0.95;平均年龄70.9岁)的185个组织病检确诊的BCCs记录在案。发病最高比例(27.1%)在8l~90岁年龄组。与普查资料相比,华人BCCs患者的比例明显增高(P〈0.001)。肿瘤平均直径为12.0mm,且大多数(84.3%)位于头颈部。28处(15.1%)皮损被不完全切除,多位于鼻部及鼻唇沟。不完全切除的基底细胞癌较完全切除的基底细胞癌更多发生于面中部及躯干部(P=0.003),但与肿瘤大小、肿瘤持续时间、患者年龄、种族及性别无显著相关。平均随访74个月, 相似文献
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Purpose: The aim of the study was to provide information about the characteristics of three main types of orthokeratology (ortho‐k) lenses used in Hong Kong and to report on their performance based on the clinical impressions of a group of ortho‐k practitioners. Method: Twelve ortho‐k practitioners were interviewed between 1 March and 30 June 2001. Results: Most ortho‐k lenses were ordered from three manufacturers: DreimLens, Fargo and Contex. The median maximum myopia reduction reported for DreimLens, Contex and Fargo lenses were 6.25 D, 6.00 D and 4.50 D respectively. The time to reduce myopia by up to 4.00 D could be up to three weeks for Contex and DreimLens and up to four weeks for Fargo. For reduction of myopia by up to 4.00 D, the treatment usually required only one or two lenses per eye for all three types of lenses. The incidence of lens binding and lens tightening after achieving the optimal reduction was reported to be higher with the DreimLens design. Good centration, less lens binding, relatively lower incidence of complications and lens tightening after achieving the optimal reduction were reported with the Fargo lenses. Conclusions: DreimLens tended to be more effective for myopia reduction. However, some practitioners were concerned with the aggressiveness of myopia reduction using this lens design and the higher potential for ocular complications. Selection of the lens design is dependent on various factors, in particular, practitioners need to be comfortable with the design they choose and to consider the needs of their patients and the final goal of the treatment. 相似文献
8.
The lectin histochemistry of ovarian mucinous cystadenoma was studied using a panel of lectins comprising Triticum vulgaris, Lotus tetragonolobus, Arachis hypogaea, Griffonia simplicifolia I, concanavalin A, and Dolichus biflorus. All 23 cases examined in this study stained extensively with T. vulgaris. Of all the lectins, D. biflorus was the least reactive. Concanavalin A stained mainly the perinuclear zone, whereas the other lectins frequently stained the cytoplasm, glycocalyx, and extracellular luminal mucin. This pattern of lectin reactivity resembles endocervical more than intestinal epithelium and suggests that ovarian mucinous cystadenomas are of müllerian nature. The lack of difference in lectin reactivity between cystadenomas with and without goblet/Paneth cells supports a common histogenetic origin of both groups. 相似文献
9.
Estrogen-induced transcortin increase and progesterone and cortisol interactions: implications from pregnancy studies 总被引:1,自引:0,他引:1
J J Evans I L Sin G B Duff C M Frampton 《Annals of clinical and laboratory science》1987,17(2):101-105
The concentrations of progesterone, cortisol, estradiol, and transcortin binding capacity (TBC) were measured in plasma samples of women during normal pregnancy. Between 10 weeks and 20 weeks gestation, the mean of TBC increased linearly, and the mean increase in TBC for a given estradiol increment was constant until the estradiol concentrations reached approximately 30 nmol per liter. The results were consistent with the increase in TBC having been induced by estradiol; however, there was an inherent upper limit of response. Progesterone and cortisol were each linearly related to TBC, but the ratios of progesterone:TBC and cortisol:TBC showed no systematic trend throughout the period studied, and there was no systematic relationship between TBC and the progesterone:cortisol ratio. There was, however, a linear relationship between TBC and the progesterone + cortisol sum, such that a unit increase in TBC was accompanied by an approximate unit increase in the total concentration of the two main transcortin binding steroids. Some cases of spontaneous abortion or habitual abortion might be due to aberrant metabolic influence on progesterone of binding protein; in the instances studied, no evidence was found for this. 相似文献
10.
An investigation of the rhizomes of ATRACTYLIS KOREANA afforded, in addition to known selinane sesquiterpenoids, an ester of tetradeca-6, 12-diene-8, 10-diyne-1,3-diol and two isomers of 6-methyl-2-geranyl- P-benzoquinone, which are new compounds for the genus Atractylis. Their structures were established by spectroscopic and chemical methods. 相似文献