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1.
绝经是一个古老的概念,见诸于文献,最早可以追溯到春秋时期中医的重要文献之一《黄帝内经》。其中,《素问·上古天真论》有这样的描述:“女子二七而天葵至,任脉通,太冲脉盛,月事以时下,故有子……七七任脉虚,太冲脉衰少,天葵竭,地道不通,故形坏而无子也。”绝经是卵巢功能衰竭所造成的一种生命现象,从理论上讲,经过长期的进化的洗礼,人体所有的器官和组织,都是维持人体生命活动不可或缺的重要组成部分。时至今日,在不同的流行病学调查中,女性平均绝经年龄仍保持在50岁左右[1-2],可谓亘古未变,而变化的是人类寿命的延长,2018年北京女性预期寿命已经达84.63岁。
浏览更多请关注本刊微信公众号及当期杂志。 相似文献
2.
《Journal of Medical Imaging and Radiation Sciences》2015,46(3):309-316
ObjectivesThe purposes of this study were to (1) investigate the limits of measurements on scout view in three computed tomography axes, x, y and z and (2) develop a model to provide better understanding of measurement accuracy.MethodsFor the first objective, anteroposterior and lateral scout views of a Catphan phantom 200 mm in diameter and length were acquired with a GE scanner at 21 different table heights. Phantom measurements on scout view were performed by two experienced readers. The comparison of their measures provided estimation of precision. The accuracy was assessed by determining the bias, calculated as the difference between the values measured on scout view and the real phantom size. Second, a model was developed investigating the relationship between the dimensions of the object, its image, and the table height. This relationship was tested on our data.ResultsScout view measurements were precise, with less than 0.53% difference between readers. In addition, small biases of about 1 mm were detected in the z-axis, whatever the table height. In the other axes, serious biases from −13 to +73 mm were measured. Furthermore, at isocentre, overestimations up to 7 mm were shown. The results also indicated that biases in scout view measurements are because of the geometrical projection related to the object-detector distance.ConclusionsMeasurements in the table movement axis are precise and accurate, conferring to scout views an added value for preoperative planning in orthopedic surgery. 相似文献
3.
4.
Yuan Peng Yuman Li Haiyan Cao Liu Hong Yu Wang Mingxing Xie 《Journal of ultrasound in medicine》2019,38(2):539-544
A pulmonary artery (PA) sling is a very rare congenital cardiovascular anomaly, and only a few studies have reported PA slings in fetuses. The relationship of the PA, aorta, ductus arteriosus, and trachea can be evaluated in the 3‐vessel and 3‐vessel and trachea views during fetal echocardiography. A PA sling can be detected by abnormal positioning of the left PA in relation to the trachea when sweeping from the 3‐vessel view cranially to the 3‐vessel and trachea view. Here we report 3 cases of fetal PA slings and their follow‐ups. Two cases were confirmed by postnatal echocardiography, and the other case was confirmed by a cardiovascular cast after pregnancy termination. We emphasize that the 3‐vessel and 3‐vessel and trachea views are of crucial importance in the prenatal diagnosis of a PA sling. 相似文献
5.
Posterior dislocations of the sternoclavicular joint are uncommon, but are potentially quite serious. Radiologic diagnosis and management are frequently difficult. The specialized projections available are not widely known, and the role of plain films is poorly understood. The incidence, pathomechanics, and clinical manifestations of such dislocations are presented and the radiologic diagnosis is discussed. 相似文献
6.
Auditory Perception and the Control of Spatially Coordinated Action of Deaf and Hearing Children 总被引:1,自引:0,他引:1
G. J. P. Savelsbergh J. B. Netelenbos H. T. A. Whiting 《Journal of child psychology and psychiatry, and allied disciplines》1991,32(3):489-500
From birth onwards, auditory stimulation directs and intensifies visual orientation behaviour. In deaf children, by definition, auditory perception cannot take place and cannot, therefore, make a contribution to visual orientation to objects approaching from outside the initial field of view. In experiment 1, a difference in catching ability is demonstrated between deaf and hearing children (10-13 years of age) when the ball approached from the periphery or from outside the field of view. No differences in catching ability between the two groups occurred when the ball approached from within the field of view. A second experiment was conducted in order to determine if differences in catching ability between deaf and hearing children could be attributed to execution of slow orientating movements and/or slow reaction time as a result of the auditory loss. The deaf children showed slower reaction times. No differences were found in movement times between deaf and hearing children. Overall, the findings suggest that a lack of auditory stimulation during development can lead to deficiencies in the coordination of actions such as catching which are both spatially and temporally constrained. 相似文献
7.
Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts. 相似文献
8.
D.R. Pina S.B. Duarte J. Morceli T. Ghilardi Netto 《Applied radiation and isotopes》2006,64(12):1623-1630
We present the construction of a homogeneous phantom to be used in simulating the scattering and absorption of X-rays by a standard patient chest and skull when irradiated laterally. This phantom consisted of lucite and aluminium plates with their thickness determined by a tomographic exploratory method applied to the anthropomorphic phantom. Using this phantom, an optimized radiographic technique was established for chest and skull of standard sized patient in lateral view. Images generated with this optimized technique demonstrated improved image quality and reduced radiation doses. 相似文献
9.
Ezgi Dogan-Sander Roland Mergl Anja Willenberg Ronny Baber Kerstin Wirkner Steffi G. Riedel-Heller Susanne Rhr Frank M. Schmidt Georg Schomerus Christian Sander 《Nutrients》2021,13(6)
Depression and vitamin D deficiency are major public health problems. The existing literature indicates the complex relationship between depression and vitamin D. The purpose of this study was to examine whether this relationship is moderated or mediated by inflammation. A community sample (n = 7162) from the LIFE-Adult-Study was investigated, for whom depressive symptoms were assessed via the German version of CES-D scale and serum 25-hydroxyvitamin D (25(OH)D) levels and inflammatory markers (IL-6 and CRP levels, WBC count) were quantified. Mediation analyses were performed using Hayes’ PROCESS macro and regression analyses were conducted to test moderation effects. There was a significant negative correlation between CES-D and 25(OH)D, and positive associations between inflammatory markers and CES-D scores. Only WBC partially mediated the association between 25(OH)D levels and depressive symptoms both in a simple mediation model (ab: −0.0042) and a model including covariates (ab: −0.0011). None of the inflammatory markers showed a moderation effect on the association between 25(OH)D levels and depressive symptoms. This present work highlighted the complex relationship between vitamin D, depressive symptoms and inflammation. Future studies are needed to examine the effect of vitamin D supplementation on inflammation and depressive symptomatology for causality assessment. 相似文献
10.
中国传统死亡观与安乐死 总被引:5,自引:0,他引:5
安乐死的本质含义应该是重病患者在不同逆地趋向死亡的过程中,无论在肉体状态还是精神状态下,都能安乐地去死,医学手段只能使人的肉体由痛苦状态转向安乐状态,而社会科学可使人的精神由痛苦状态转向发乐状态。文章从死亡是人生的自然归宿、是一种心理巩具、死亡是对现实 痛苦解脱三个方面探讨了中国传统死亡观对安乐死被认同和实施 的重大影响,以引起人们对此 关注。 相似文献