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81.
Yaotang Wu Guangping Dai Jerome L Ackerman Mirko I Hrovat Melvin J Glimcher Brian D Snyder Ara Nazarian David A Chesler 《Magnetic resonance in medicine》2007,57(3):554-567
Investigators often study rats by microCT to investigate the pathogenesis and treatment of skeletal disorders in humans. However, microCT measurements provide information only on bone mineral content and not the solid matrix. CT scans are often carried out on cancellous bone, which contains a significant volume of marrow cells, stroma, water, and fat, and thus the apparent bone mineral density (BMD) does not reflect the mineral density within the matrix, where the mineral crystals are localized. Water- and fat-suppressed solid-state proton projection imaging (WASPI) was utilized in this study to image the solid matrix content (collagen, tightly bound water, and other immobile molecules) of rat femur specimens, and meet the challenges of small sample size and demanding submillimeter resolution. A method is introduced to recover the central region of k-space, which is always lost in the receiver dead time when free induction decays (FIDs) are acquired. With this approach, points near the k-space origin are sampled under a small number of radial projections at reduced gradient strength. The typical scan time for the current WASPI experiments was 2 hr. Proton solid-matrix images of rat femurs with 0.4-mm resolution and 12-mm field of view (FOV) were obtained. This method provides a noninvasive means of studying bone matrix in small animals. 相似文献
82.
Persons with haemophilia often experience their first joint haemorrhage in early childhood. Recurrent bleeding into a joint may lead to significant morbidity, specifically haemophilic arthropathy. Early identification of the onset and progression of joint damage is critical to preserving joint structure and function. Physical examination is the most feasible approach to monitor joint health. Our group developed the Colorado Haemophilia Paediatric Joint Physical Examination Scale to identify earlier signs of joint degeneration and incorporate developmentally appropriate tasks for assessing joint function in young children. This study's objectives were to establish normal ranges for this scale and assess interrater reliability. The ankles, knees and elbows of 72 healthy boys aged 1 through 7 years were evaluated by a physical therapist to establish normal ranges. Exactly 10 boys in each age category from 2 to 7 years were evaluated by a second physical therapist to determine interrater reliability. The original scale was modified to account for the finding that mild angulation in the weight-bearing joints is developmentally normal. The interrater reliability of the scale ranged from fair to good, underscoring the need for physical therapists to have specific training in the orthopaedic assessment of very young children and the measurement error inherent in the goniometer. Modifications to axial alignment scoring will allow the scale to distinguish healthy joints from those suffering frequent haemarthroses. 相似文献
83.
蛇毒抗高凝状态酶、氟尿嘧啶对BEL-7404细胞作用的实验研究 总被引:1,自引:0,他引:1
目的通过蛇毒抗高凝状态酶(AHCSE)、氟尿嘧啶(5-FU)对人肝癌细胞BEL-7404(简称7404细胞)、正常LO2肝细胞(简称LO2细胞)作用的比较,研究AHCSE对肝癌的作用以及探讨其可能的作用机制。方法应用光学显微镜、透射电镜、MTT法、TUNEL、FCM等方法观察7404细胞、LO2细胞经过AHCSE、5-FU处理后,细胞形态学、生物化学等方面的变化。结果7404细胞、LO2细胞经过AHCSE、52FU处理后,发生了形态学改变;小剂量AHCSE对7404细胞具有很强的抑制作用,但对LO2细胞几乎无影响;随着剂量的加大,AHCSE对7404细胞抑制率上升不明显,但是出现对LO2细胞的抑制作用。经AHCSE作用后,7404细胞发生了凋亡,凋亡率随AHCSE浓度的增加而增加;与5-FU对7404细胞作用相似,但5-FU对LO2细胞抑制作用明显增强。结论AHCSE、5-FU对BEL-7404细胞均有很强的抑制作用,诱导细胞凋亡是其作用机制之一,AHCSE可能成为一种新的肝癌细胞凋亡的诱导剂。 相似文献
84.
Although anxiety is a well-established obstacle to the delivery of effective health care, there have been no attempts to measure it in the optometric consulting room. In this paper, we introduce physiological and psychological techniques that may be used to evaluate anxiety and arousal in the consulting room and present data from a small group of patients attending for a routine eye examination. Specifically, arousal was assessed before, during, and after the examination by measuring skin conductance in five patients. Anxiety was evaluated using the State-Trait Anxiety Inventory. Our data confirm the ability of these techniques to quantify arousal and anxiety in the optometric consulting room and reveal a previously unknown but important facet of the eye examination. We conclude that these techniques are suitable for use in further experimental work and may be used to identify factors capable of reducing anxiety in the optometric consulting room. 相似文献
85.
佛山市城区集体儿童健康状况调查分析 总被引:1,自引:0,他引:1
目的了解佛山市城区集体儿童健康状况,以制定干预措施。方法采用随机整群抽样的方法,抽取本市城区共15间幼儿园,并对各间园所的儿童体检的资料数据进行整理和分析。结果佛山市集体儿童缺点总检出率为71.40%。其中私营幼儿园儿童缺点患病率明显高于事业单位的幼儿园(P<0.05),有显著性差异。儿童骨矿物质测定缺钙的检出率为13.73%。男女儿童无性别差异。结论今后继续加强对幼儿园的管理工作,私营的幼儿园管理工作是我们今后管理工作的重点,做好防治工作,降低患病率,增强儿童的身心健康。 相似文献
86.
胃壁内迷走胰腺的X线征象 总被引:1,自引:0,他引:1
陈耀辉 《实用医学影像杂志》2007,8(5):301-302
目的提高对胃壁内迷走胰腺的认识。方法回顾性分析4例手术病理证实的胃壁内迷走胰腺的临床和钡餐检查X线表现。结果4例胃壁内迷走胰腺均发生在胃窦部近幽门区大弯侧,钡餐表现为轮廓较光滑的圆形或卵圆形充盈缺损,直径1~4cm,形态、位置固定,不随胃蠕动或触压而改变;临近黏膜可规整或粗乱,其中,典型的"脐样"征1例。结论主要X线征象为位于胃窦部幽门区大弯侧边缘光滑、位置固定、无溃疡的充盈缺损,难与息肉或平滑肌瘤或间质瘤等鉴别。 相似文献
87.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(6):567-574
The development of combined microwave‐enhanced/parallel synthesis procedures and their application to the deuteriation of organic compounds via examples of solid‐state hydrogenation is reported. Other labelling procedures, such as solution state catalytic dehalogenations, hydrogenations as well as hydrogen isotope exchange reactions also benefit from the combined technology. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
88.
In recent years many studies of unemployment and health haveshown that unemployed persons are in poorer health. However,one question remained unanswered: is the poorer health of theunemployed caused by unemployment Itself (causation hypotheses)or is it a result of selection processes, whereby people inpoor health are more likely to lose their job and less likelyto be re-employed (selection hypothesis)? Findings from a studybased on the longitudinal data of the German Socio-economicPanel (19841988, N=5, 516 persons, 1864 years)are presented. All health indicators (health satisfaction, chronicillness, handicaps in fulfilling daily life tasks, disability)showed poorer outcomes for the unemployed persons, even aftercontrolling for the possible confounding effects of sodo-demographicvariables. Unemployed persons also consulted a physician morefrequently and were hospitalized more often. But longitudinalanalyses (of becoming unemployed and of re-employment) did notlend much support to the causation hypothesis. Instead, a constantlevel of health satisfaction for persons losing their job andfor the re-employed compared to their initial ratings supportedthe selection hypotheses. This means that in the Federal Republicof Germany persons in poorer health are more likely to losetheir jobs and persons in better health are more likely to bere-employed. 相似文献
89.
J. M. Wardlaw M. S. Dennis R. I. Lindley R. J. Sellar C. P. Wadaw 《Journal of neurology》1996,243(3):274-279
The aim of the study reported here was to test the validity of a simple clinical classification of acute ischaemic stroke (Oxfordshire Community Stroke Project, OCSP) in predicting the site and size of cerebral infarction on computed tomography (CT). Consecutive patients admitted to hospital with acute ischaemic stroke were prospectively identified and classified into one of four clinical syndromes according to the OCSP classification, blind to the result of CT. The CT brain scans were classified blind to the clinical features into those demonstrating: small, medium or large cortical infarcts; small or large subcortical infarcts in the anterior circulation territory; and posterior cerebral circulation territory infarcts. A total of 108 patients were included. A recent infarct was seen. on the CT scan in 91 patients (84%), and the clinical classification correctly predicted the site and size of the cerebral infarct in 80 of these (88%; 95% confidence interval 77–92%). The positive predictive value was best for large cortical infarcts (0.94) and worst for small subcortical infarcts (0.63). The OCSP clinical classification is a reasonably valid way of predicting the site and size of cerebral infarction on CT and can, therefore, be used very early after stroke onset before the infarct appears on the scan. 相似文献
90.
HBV血清学标记携带者的传染受许多因素的影响。本研究采用多因素分析方法,定量描述了各种类型HBV血清学标记携带者家庭内传染性及有关因素影响的大小。家中上次HBsAg携带与易感者HBsAg和HBeAg阳转呈正相关。家中上次抗-HBc携带与易感者抗-HBc阳转呈正相关,OR=5.98;但与抗-HBc滴度变化无显著联系。而家中上次抗-HBc携带,HBsAg与抗-HBc同时携带与易感者HBsAg和HBeAg阳转呈负相关。年龄与HBsAg阳转呈负相关;文化水平与易感者抗-HBs阳转亦呈负相关;手术史、注射史与乙肝续发感染正相关。多因素分析对阐明人群中大量HBV血清学标记携带者的动态变化有一定意义。 相似文献