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11.
Around 6% of infants born to mothers taking anticonvulsants have malformations, including neural tube defects, and a further proportion show developmental delay in later childhood. Three commonly used anticonvulsants, carbamazepine, phenytoin and sodium valproate, interfere with folic acid metabolism. We investigated the common 677 C>T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene in samples from 57 patients and their parents and 152 controls to determine its contribution to the risk of fetal anticonvulsant syndrome. The 677 C>T mutation frequency was significantly higher in the mothers than in the controls, but there was no significant difference in 677 C>T frequency in the patients or in the fathers. Genotype frequencies in the mothers were significantly different from controls, there being an excess of 677 C>T homozygotes. Amongst the patients, there was an apparent excess of heterozygotes (not statistically significant), and the fathers were not significantly different from controls. Mutation in the MTHFR gene in a mother taking sodium valproate, phenytoin or carbamazepine during pregnancy is associated with fetal anticonvulsant syndrome in her offspring. The skewed distribution of genotypes in the affected children probably reflects the association of fetal anticonvulsant syndrome with the maternal genotype.  相似文献   
12.
A parametric phase delay estimation technique is used to determine the spatial and inhaled gas composition dependencies of sound propagation time through an intact human lung at frequencies of 150–1200 Hz. Noise transmission measurements from the mouth to the extrathoracic trachea and six sites on the posterior chest wall are performed in 11 healthy adult subjects at resting lung volume after equilibration with air, an 80% helium-20% oxygen mixture, and an 80% sulfurhexafluoride-20% oxygen mixture. The phase delay, τ(f), exhibits a bilateral asymmetry with relatively decreased delays to the left posterior chest as compared with the right. The phase delay to lower lung sites is greater than to upper sites at frequencies below 300 Hz; yet the opposite is found at higher frequencies, indicating changing propagation pathways with frequency. There is no measurable effect of inhaled gas composition on τ(f) below 300 Hz. At higher frequencies, changes in τ(f) that reflect the relative sound speed of the particular inhaled gas are observed. These findings support and extend previous measurements and hypotheses concerning the strong frequency dependence of the acoustical properties of the intact respiratory system.  相似文献   
13.
Summary In order to investigate the relationship between metabolic state and myoelectrical activity in working muscle during short term intense exercise, eleven healthy males performed isokinetic knee extensions at an angular velocity of 180 deg · sec–1 for 30 and 60 s. The median frequency (MF) of the surface electromyogram (EMG) recorded from vastus lateralis was decreased while the time lag of torque production after the onset of electrical activity (EMD) was increased during exercise. These changes (MF and EMD) corresponded well to muscle lactate accumulation in the same muscle. Over the exercise period, the integrated EMG/knee extension peak torque ratio (E/T ratio) was increased, which indicated a decrease in the efficiency of electrical activity. It was concluded that the changes in the frequency components of the EMG and in the contractile property of the muscle during short term intense exercise correlated with lactate accumulation in the identical muscle, and that the decrease in efficiency of the electrical activity in the muscle suggested peripheral fatigue.  相似文献   
14.
目的 调查发育迟缓儿童的自我意识水平,并探讨焦虑在家庭亲密度与自我意识的中介作用。方法 采取便利抽样法,于2019年7月—2021年4月抽取辽宁省某医院儿科门诊就诊和复查的200例发育迟缓儿童作为研究对象。采用一般资料调查问卷、家庭亲密度与适应性量表(FACES-Ⅱ)、儿童焦虑量表与儿童自我意识量表进行调查。结果 200例发育迟缓儿童的自我意识总分为45.87±4.15,FACES-Ⅱ得分与自我意识总分呈负相关 (r=-0.607,P<0.01);FACES-Ⅱ得分与儿童焦虑呈正相关(r=0.416,P<0.001);儿童焦虑与自我意识呈负相关(r=-0.367,P<0.01)。中介效应检验结果显示,儿童焦虑在家庭亲密度对自我意识之间存在显著的部分中介效应,95%CI为(-0.257,-0.043)。中介效应值为-0.077,占总效应的9.50%。 结论 发育迟缓儿童自我意识较低,要重点关注对儿童焦虑情绪的疏导,营造良好的家庭氛围和融洽的亲子关系,提高发育迟缓儿童心理健康与自我意识水平。  相似文献   
15.
周瑛  王晨 《中国儿童保健杂志》2021,29(12):1368-1371
目的 分析幼儿语言发育迟缓(LDD)的家庭环境因素,为LDD早期干预提供依据。 方法 选择2020年7月28日—2021年1月27日于北京协和医院儿童保健门诊诊断为LDD的55例16~30个月龄幼儿作为病例组,筛选同期正常儿保查体的同年龄组71例幼儿作为对照组,使用中文早期语言与沟通发展量表普通话版作为标准化评估工具,并对父母和主要照养人的文化水平、家庭环境、出生情况进行问卷调查,分析各因素与幼儿语言发育落后的相关性。 结果 两组家庭环境有方言情况差异无统计学意义(P>0.05)。与对照组相比,LDD组独生子女家庭比例少,父母及主要照养人本科及以上文化程度稍少,保姆或(外)祖父为主要照养人比例更多,幼儿屏幕时间较长,开始观看屏幕月龄更小,更多幼儿的父母陪伴时间<2 h/d、屏幕时间≥2 h/d、开始观看屏幕月龄<12月,差异有统计学意义(P<0.05)。Logistic回归分析显示:开始观看屏幕月龄<12月(OR=9.562,95%CI:3.106~29.437)、屏幕时间≥2 h/d (OR=3.222,95%CI:1.169~8.884)、主要照养人是(外)祖父或保姆(OR=7.034,95%CI:1.930~25.634)是幼儿语言发育落后的危险因素(P<0.05)。 结论 屏幕暴露年龄过早、屏幕暴露过长以及(外)祖父或保姆作为主要照养人是幼儿语言发育迟缓的危险因素。应避免婴幼儿过早或过长时间观看媒体屏幕,鼓励父母照料幼儿。  相似文献   
16.
This research provides a new framework based on a hybrid of block‐pulse functions and Legendre polynomials for the numerical examination of a special class of scalar nonlinear fractional optimal control problems involving delay. The concepts of the fractional derivative and the fractional integral are employed in the Caputo sense and the Riemann‐Liouville sense, respectively. In accordance with the notion of the Riemann‐Liouville integral, we derive a new integral operator related to the proposed basis called the operational matrix of fractional integration. By employing two significant operators, namely, the delay operator and the integral operator connected to the hybrid basis, the system dynamics of the primal optimal control problem converts to another system involving algebraic equations. Consequently, the optimal control problem under study is reduced to a static optimization one that is solved by existing well‐established optimization procedures. Some new theoretical results regarding the new basis are obtained. Various kinds of fractional optimal control problems containing delay are examined to measure the accuracy of the new method. The simulation results justify the merits and superiority of the devised procedure over the existing optimization methods in the literature.  相似文献   
17.
18.
Partial monosomy of 6q resulting from an interstitial deletion of bands q16----q22 was found in a 12-year-old boy manifesting mental retardation, seizure disorder, and dysmorphic features. The correlation of phenotypic expression and specific long arm deletions of chromosome No. 6 is discussed.  相似文献   
19.
脑梗塞患者治疗时间延误原因及对策   总被引:5,自引:0,他引:5  
为探讨脑梗塞患者治疗时间的延误原因和对策,对河北、内蒙古部分地区脑梗塞患者治疗时间延误的原因进行了调查分析。共调查了脑梗塞患者1048例,在6小时内接受治疗的人数为326例,占31.11%;在24小时内,接受治疗的人数为566例,占54.01%;在25小时后,接受治疗的人数为482例,占45.99%。脑梗塞患者治疗延误时间为23.55小时,其院前的延误时间为21.49小时,占91.25%,院后的延误时间为2.06小时,占8.75%。调查发现,对脑梗塞患者实施早期治疗,必须在社区内进一步加强脑梗塞症状学和及早诊治意义的科普教育;提高医务人员对脑梗塞诊治水平和治疗紧迫性的认识,建立和完善医院的快速反应系统。只有这样,脑梗塞的早期治疗,才会有根本性的改善  相似文献   
20.
The aim of the present study was to investigate whether cisplatin would enhance the radioresponse of a human tumour xenograft when given in different schedules combined with accelerated fractionated radiation therapy. A human squamous carcinoma of the hypopharynx, FaDu, was grown in the thigh of athymic nude mice. Tumours were exposed to twice-daily 2-Gy fractions, applied 6 h apart over 2 weeks, 5 days a week, alone or combined with cisplatin given at maximally tolerated doses in three different schedules: (1) i.p. as a single bolus (SB) or (2) i.p. as a daily bolus at 30 min before the first daily radiation fraction or (3) s.c. as a continuous infusion through a mini-osmotic pump over 13 days, commencing 24 h prior to the first daily radiation fraction. The end point for the study was tumour growth delay (TGD), calculated as the difference between the delay in regrowth to 200% of the initial tumour size in treated versus control mice. SB cisplatin plus radiation showed only an additive effect on TGD, whereas daily-bolus and continuous-infusion cisplatin demonstrated a greater than additive effect when combined with accelerated fractionated radiation in this human tumour model. Cisplatin appears to be especially beneficial as a radiation enhancer when given throughout the course of radiation. Received: 15 December 1996 / Accepted: 25 March 1997  相似文献   
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