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81.
While the appropriate method for the investigation of female infertility continues to be debated, the timing of the investigation has received less attention. The current approach is time-consuming, and paradoxically may lead to overtreatment as well as undertreatment. Recent findings on fecundity and the conception window in humans have important implications for the timing of the investigation of female infertility. The findings support the view that fertility-oriented intercourse may have a major impact in reducing the time to pregnancy. Procedures for the investigation of female infertility are becoming less invasive and more accurate, while the therapies for infertility are more effective. It is proposed that under appropriate circumstances female infertility should be investigated after 6 months of fertility-oriented intercourse.  相似文献   
82.
目的探讨抑郁障碍患者与家属的家庭亲密度适应性和情绪状况,为抑郁障碍患者的健康教育及家庭干预提供科学有效的理论依据。方法选择2006年6~9月在北京大学第六医院就诊的抑郁障碍患者95例及共同陪伴的直系家属95例为调查对象。采用家庭亲密度和适应性量表中文版(FACES-CV)、Zung氏焦虑自评量表和Zung氏抑郁自评量表。结果1患者的家庭亲密度得分与国内常模一致(P>0.05),但适应性得分低于国内常模(P<0.01);焦虑、抑郁得分高于国内常模(P<0.01)。家属的家庭亲密度得分高于国内常模(P<0.01),适应性得分低于国内常模(P<0.01)。家属的焦虑得分与国内常模一致(P>0.05),但抑郁得分高于国内常模(P<0.05)。2家庭模式分型构成比:中间型47.9%,平衡性26.3%,极端型25.8%。患者的家庭"拱极模式"以"僵硬—松散型"居多,家属则以"自由—缠结型"居多。3家庭亲密度与患者的家属的文程化度有关,相关系数范围(r=0.21~0.26,P<0.05)、与家庭人数呈负相关(r=-0.21,P<0.01);与患者及家属的焦虑、抑郁情绪呈显著负相关,相关系数范围(r=-0.30~0.37,P<0.01);家庭适应性与患者的年龄(r=0.28,P<0.01)、文化程度(r=0.34,P<0.01)有关。与家属的年龄(r=0.26,P<0.05)文化程度(r=0.22,P<0.05)有关。与患者和家属的焦虑、抑郁情绪呈显著负相关,相关系数范围(r=-0.30~-0.42,P<0.01)。结论家庭亲密度适应性与患者和家属的文化程度、焦虑、抑郁情绪有关,家庭亲密度与患者的家庭人数有关,家庭适应性与患者和家属的年龄有关。  相似文献   
83.
Recent developments in medical image acquisition combined with the latest advancements in numerical methods for solving the Navier-Stokes equations have created unprecedented opportunities for developing simple and reliable computational fluid dynamics (CFD) tools for meeting patient-specific surgical planning objectives. However, for CFD to reach its full potential and gain the trust and confidence of medical practitioners, physics-driven numerical modeling is required. This study reports on the experience gained from an ongoing integrated CFD modeling effort aimed at developing an advanced numerical simulation tool capable of accurately predicting flow characteristics in an anatomically correct total cavopulmonary connection (TCPC). An anatomical intra-atrial TCPC model is reconstructed from a stack of magnetic resonance (MR) images acquired in vivo. An exact replica of the computational geometry was built using transparent rapid prototyping. Following the same approach as in earlier studies on idealized models, flow structures, pressure drops, and energy losses were assessed both numerically and experimentally, then compared. Numerical studies were performed with both a first-order accurate commercial software and a recently developed, second-order accurate, in-house flow solver. The commercial CFD model could, with reasonable accuracy, capture global flow quantities of interest such as control volume power losses and pressure drops and time-averaged flow patterns. However, for steady inflow conditions, both flow visualization experiments and particle image velocimetry (PIV) measurements revealed unsteady, complex, and highly 3D flow structures, which could not be captured by this numerical model with the available computational resources and additional modeling efforts that are described. Preliminary time-accurate computations with the in-house flow solver were shown to capture for the first time these complex flow features and yielded solutions in good agreement with the experimental observations. Flow fields obtained were similar for the studied total cardiac output range (1–3 l/min); however hydrodynamic power loss increased dramatically with increasing cardiac output, suggesting significant energy demand at exercise conditions. The simulation of cardiovascular flows poses a formidable challenge to even the most advanced CFD tools currently available. A successful prediction requires a two-pronged, physics-based approach, which integrates high-resolution CFD tools and high-resolution laboratory measurements.  相似文献   
84.
Doris  Weipert  David  Shapiro  Thomas  Suter 《Psychophysiology》1987,24(3):251-257
Cardiovascular effects of orthostatic stress (sitting to standing) were assessed in 60 healthy young male subjects according lo family history of hypertension (half with a positive and half with a negative family history' of hypertension). Systolic (SBP) and diastolic blood pressure (DBF) were recorded on each successive heart heal using a non-invasive blood pressure tracking system. Heart rate (HR) and respiration rate (RR) were also recorded. During the postural change, characteristic phasic changes were shown with an initial fall and subsequent recover of SBP and DBF and a mirror image response in MR and RR. Phasic analysis of the pre-standing sit, peak/trough, and recovery stand values indicated group differences in the initial as well as the later phases of orthostatic response. In the initial phase, subjects with a positive family history of hypertension showed an earlier trough in systolic and pulse pressure and an earlier peak in heart rate response immediately on standing up. The level of the pulse pressure trough was also higher in these subjects. In the later standing phase, these subjects showed higher levels of pulse pressure. The results were interpreted in terms of increased sympathetic nervous system activity during the initial phase and structural and neurocirculatory abnormalities in the later phase of orthostatic regulation in individuals with a positive family history of hypertension.  相似文献   
85.
目的:了解单纯对立违抗性障碍(ODD)儿童的父母养育方式及家庭功能。方法:应用向制儿童行为调查表、家庭环境量表中文版(FES~CV)、父母养育方式量表(EMBU),对115例单纯ODD儿童(研究组)和115名非ODD正常儿童(对照组)进行评定和病例对照分析,结果:ODD组儿童家庭矛盾性得分较对照组高(P〈0.01),ODD组父母双亲的“情感温暖.理解”得分均明显比对照组得分低(父亲P〈0.01,母亲P〈0.05).而其“惩罚,严厉”和“拒绝,否认”二因子得分则明显比对照组高(P〈0.01);ODD组母亲的“过分干涉,过度保护”,因子得分也明显高于对照组(P〈0.01)。结论:ODD中学生的家庭存在高度的矛盾性.他们的父母养育方式不良,应引起重视。  相似文献   
86.
目的 寻找由DNA损伤引起的人类表型缺陷,为人类遗传资源的收集与保藏以及人类基因结构与功能的研究打下基础。方法 通过实地调查得到表型缺陷家系,然后进行系谱分析。结果 得到一个遗传性智力迟缓家系,3代11位成员中有2例患者。结论 遗传性智力迟缓是由DNA损伤引起的人类表型缺陷;该病症符合X-连锁隐性遗传。  相似文献   
87.
SAGE是集多功能于一体的医学遗传学群体与家系资料计算机分析系统。本文概述SAGE系统的主要功能及应用环境。重点介绍了FCOR2和TDTEX两个功能模块的数学原理和使用方法。应用TDTEX模块 ,我们发现微卫星标记 85ca与小儿失神症存在连锁不平衡 ,提示在该位点附近存在小儿失神症的易感基因  相似文献   
88.
目的 探讨各种阈值校正方法对统计参数图(SPM)软件统计比较结果显示的影响.方法 利用Hoffman标准脑模型制作缺损模型PET成像与正常模型PET成像,进行统计参数图的统计比较.并选取脑梗死患者与健康检查者进行统计参数图的统计比较.结果 校正与非校正产生的结果有差异,其中族错误率(FWE)校正(P=5×10-2)得到的统计分析结果激活区最少及最小,其次是错误发现率(FDR)校正(P=5×10-2),非校正方式(P=1×10-3)得到的激活区最多及最大.但FDR校正效果不稳定,有时不如不校正.结论 统计参数图软件中FWE校正方法可明显降低假阳性,得到的结果可信度稳定地高于非校正方法.  相似文献   
89.
Appropriate deployment of technological innovation contributes to improvement in the quality of healthcare delivered, containment of cost, and an increased access to the healthcare system. Hospitals have been allocating a, significant portion of their resources to procuring and managing capital assets; they are continously faced with demands for new medical equipment and are, asked to manage existing inventory for which they are not well prepared. To objectively manage their investment, hospitals are developing medical technology management programmes that need pertinent information and methods for new equipment planning as well as for reduction in the ownership costs of existing equipment. Clinical engineers can identify new medical equipment, review their institution's technological position, develop equipment-selection criteria, supervise installations and monitor postprocurement performance to meet their hospital's programme's objectives. This programme, together with cost accounting analysis, will objectively guide the capital assets decisionmaking process. The result of systematic planning and execution, the programme will assure the lowest life-cycle costs at the best performance. The clinical engineer's skills and expertise are needed to facilitate the adoption of an objective methodology for implementing the programme, thus improving the match between the hospital's needs and budget projections, equipment performance and cost of ownership.  相似文献   
90.
Summary Upper lip, lower lip, and jaw kinematics during select speech behaviors were studied in an attempt to identify potential invariant characteristics associated with this highly skilled motor behavior. Data indicated that speech motor actions are executed and planned presumably in terms of relatively invariant combined multimovement gestures. In contrast, the individual upper lip, lower lip, and jaw movements and their moment-to-moment coordination were executed in a variable manner, demonstrating substantial motor equivalence. Based on the trial-to-trial variability in the movement amplitudes, absolute positions, and velocities of the upper lip, lower lip, and jaw, it appears that speech motor planning is not formulated in terms of spatial coordinates. Seemingly, object-level planning for speech may be encoded in relation to the acoustic consequences of the movements and ultimately with regard to listener's auditory perceptions. In addition, certain temporal parameters among the three movements (relative times of movement onsets and velocity peaks) were related stereotypically, reflecting invariances characteristic of more automatic motor behaviors such as chewing and locomotion. These data thus appear to provide some additional insights into the hierarchy of multimovement control. At the top of the motor control hierarchy, the overall plan appears to be generated with explicit specification of certain temporal parameters. Subsequently, based upon the plan and within that stereotypic temporal framework, covariable adjustments among the individual movements are implemented. Given the results of previous perturbation studies, it is hypothesized that these covariable velocity and amplitude adjustments reflect the action of sensorimptor mechanisms.  相似文献   
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