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161.
Iosif W. Lurie 《American journal of medical genetics. Part A》1994,50(4):313-317
Six familial cases of the Beemer–Langer syndrome (BLS) were analyzed to further elucidate the spectrum and frequency of anomalies observed in this disorder. Preaxial polydactyly was found in 3/6 affected sibs, and, therefore, its frequency previously may have been underestimated. Some patients, described as infants affected with the Majewski syndrome (MS) or “atypical” short rib-poly-dactyly conditions, may indeed have BLS. A high frequency of brain defects (16/26) and cleft tongue, oral frenula, and/or natal teeth (13/29) widens the list of typical findings in this syndrome. The specific type of tibial defect seems to be the most important discrimination of the MS and the BLS. © 1994 Wiley-Liss, Inc. 相似文献
162.
Janice S. Lee Carol W. Bassim Harvey Kushner Ann G. Carr Pamela J. Gardner Laura A. Harney Kris Ann P. Schultz Douglas R. Stewart 《American journal of medical genetics. Part A》2019,179(9):1820-1825
Pathogenic germline variation in the microRNA processing gene DICER1 gives rise to an autosomal dominant, tumor‐predisposition disorder. Conditional deletion of Dicer1 in murine dental epithelium shows that it controls tooth patterning, size, number, and shape. The human dental phenotype of people with germline pathogenic variation in DICER1 is unknown. DICER1‐carriers (n = 57) and family controls (n = 55) were evaluated at the NIH Clinical Center dental clinic as part of a comprehensive medical evaluation. Digital panoramic radiographs, bite‐wing radiographs, and oral photographs were collected. A single observer, blind to DICER1 status, reviewed the dental records and determined the presence or absence of 11 dental characteristics as described in the clinic notes, radiographs, or oral photographs. Subjective phenotypes were reviewed on radiographs by two examiners (blind to DICER1 status) for the presence or absence of the dental characteristics to reduce inconsistencies. By simple association, bulbous crown, periodontitis, and taurodontism were all significant (p < .05). Logistic regression with chi‐square maximum likelihood estimates showed that bulbous crown and periodontitis remained significant. Recognition of these phenotypes may aid identification of individuals and families at risk for DICER1‐associated neoplasms. These findings may also guide dental care for individuals with germline DICER1 pathogenic variation. 相似文献
163.
In addition to entraining circadian rhythms, light has acute effects on sleep and wakefulness in mammals. To determine whether light and darkness have similar effects in birds, the only non-mammalian group that displays sleep patterns comparable to mammals, we examined the effects of lighting changes on sleep and wakefulness in the pigeon. We quantified sleep behavior (i.e., bilateral or unilateral eye closure) in pigeons maintained under a 12:12 LD cycle, and immediately following a change from a 12:12 to a 3:3 LD cycle. During both LD cycles, sleep was most prevalent during dark periods. During the 3:3 LD cycle, darkness had the greatest sleep promoting effect during the hours corresponding to the subjective night of the preceding 12:12 LD cycle, whereas light suppressed sleep across circadian phases. As previously suggested, the light-induced decrease in sleep in the subjective night might be partly mediated by the suppression of melatonin by light. Although the sleep promoting effect of darkness was modulated by the circadian rhythm, sleep in darkness occurred during all circadian phases, suggesting that darkness per se may play a direct role in inducing sleep. In addition to the effects of lighting on behavioral state, we observed an overall bias toward more right eye closure under all lighting conditions, possibly reflecting a response to the novel testing environment. 相似文献
164.
165.
As a further test of the hypothesis that REM deprivation decreases fear, the behavior of 40 male rats was measured in a Y-maze adapted to test for preference for novelty. Prior to this test, the animals were exposed for 4 days to one of four treatments, i.e., either a dry environment control, a wet environment control, a 2-day REM deprivation period or a 4-day REM deprivation period. During the test both number of grid crossing in the novel and non-novel arms of the Y-maze and three indices of emotionality were recorded. The results were congruent with data we had reported earlier and offered convincing evidence in support of the hypothesis. 相似文献
166.
正常成人上呼吸道CT测量及其意义 总被引:8,自引:0,他引:8
目的:确定正常人的上呼吸道CT扫描下各平面的横截面积、经线长度以及咽壁厚度,为临床服务。方法:无明显睡眠呼吸疾病史的成年人(男115、女110),采用Philips Tomoscan AV Expander E1螺旋CT,对鼻咽顶部到声门之间的区域进行连续扫描,测量软腭后区、悬雍垂后区、舌后区和会厌后区的气道横截面积、失状径、冠状径、咽侧壁和咽后壁软组织厚度,以单侧95%可信区间确定各测量指标的参考值。结果:在上呼吸道各个扫描平面,绝大多数气道的形状均为横椭圆形,冠状径大于失状径,在软腭后区、悬雍垂后区、舌后区和会厌后区中,失状径大于冠状径者分别占总人数的3.11%、10.67%、0.8%和0%。各年龄组间比较,绝大多数测量指标差异不显著,男子组和女子组间比较,除软腭后区外,大多数测量指标差异显著。故分别制定了男、女各测量指标的还范围。结论:成人上呼吸道CT测量以及正常范围的确定为临床判定OSAS患者上呼吸道解剖性狭窄的部位提供了客观依据,男性OSAS发病率明显高于女性有其相关的生理基础。 相似文献
167.
Strohl KP 《Respiratory physiology & neurobiology》2003,135(2-3):179-185
The episodic waxing and waning of ventilation is a fundamental event in sleep apnea syndromes. Post-hypoxic frequency decline (PHFD) and periodic breathing (PB) are evoked by brief hypoxic exposures in unanaesthetized and unrestrained inbred C57BL/6J mice, but not in A/J mice; and expression of PHFD differs not only among these mice strains but in among rat strains as well. These observations along with the current literature on genetic factors that operate on ventilatory behavior at rest and with chemosensory drive lead to the hypothesis that genetic factors infer some proportion of risk for the ventilatory instability observed in human sleep apnea syndromes. 相似文献
168.
目的 了解河南城市学龄前儿童睡眠状况及其影响因素,为该地区学龄前儿童保持合理睡眠时间和睡眠干预提供参考。方法 2019年5—6月采用分层整群抽样的方法在河南对4 226名3~6岁学龄前儿童家长进行儿童睡眠状况及影响因素的调查,并采用χ2检验、logistic回归分析等方法进行分析。结果 河南城市学龄前儿童平均睡眠时长为(9.46±1.98)h,睡眠不足的比例为56.60%。在体力活动时间、视屏时间、抚养者、父亲学历、母亲学历等方面睡眠不足的比例相比较均有统计学意义(χ2 = 46.853、48.424、27.763、19.654、20.063,P<0.001)。Logistic回归分析表明,河南城市>4~4.5岁(OR = 1.313,95%CI:1.064~1.567)、>4.5~5岁(OR = 1.982,95%CI:1.627~2.355)、>5~5.5岁(OR = 2.052,95%CI:1.674~2.435)、>5.5~6岁(OR = 2.374,95%CI:1.812~2.944)学龄前儿童、体力活动时间<60 min/d(OR = 1.745,95%CI:1.483~2.011)、体力活动时间60~120 min/d(OR = 1.481,95%CI:1.251~1.722)、外祖父母等抚养(OR = 1.222,95%CI:1.061~1.381)、母亲学历初中及以下(OR = 1.364,95%CI:1.147~1.595)、母亲学历高中(OR = 1.171,95%CI:1.024~1.321)者其学龄前儿童的睡眠不足发生率较高,呈正相关关系。结论 河南学龄前儿童睡眠不足问题凸显,年龄、体力活动、视屏时间、抚养者、母亲学历等是导致睡眠不足的影响因素,应针对影响因素给予干预和改善。 相似文献
169.
目的 研究广东省中老年人群睡眠状况与高血压患病的关联性,为高血压防控“关口前移”提供科学依据。方法 采用“2018年广东省慢性病及危险因素监测数据”,按照多阶段整群随机抽样方法,纳入5 636名≥45岁中老年人为研究对象。运用SAS 9.4软件进行Rao-Scott 检验和基于复杂抽样构建logistic回归模型分析睡眠状况与高血压患病的关系。运用R 4.0.5软件绘制限制性立方样条曲线分析睡眠时间与高血压患病风险的量效关系。结果 广东省中老年人高血压患病率是37.93%,平均睡眠时间是(7.36±1.61)h; 其中男性平均睡眠时间多于女性,而女性睡眠问题比例显著高于男性。经多因素回归模型控制后,睡眠时间不足或过多(OR=1.280,95%CI:1.128~1.452; OR=1.300,95%CI:1.038~1.627)、入睡困难(OR=1.286,95%CI:1.018~1.626)、中间觉醒≥2次(OR=1.239,95%CI:1.036~1.483)和服用安眠药(OR=1.567,95%CI:1.086~2.261)均使高血压患病风险升高。结论 广东省中老年人群的睡眠时间不足或过多、入睡困难、中间觉醒≥2次和服用安眠药均与高血压患病显著正相关,应对该特征的人群进行干预,旨在降低高血压的患病率。 相似文献
170.
目的 探索青少年网络成瘾和睡眠时长在受校园欺凌与抑郁关系之间的中介作用,为青少年抑郁的预防干预提供依据。 方法 使用青少年健康相关危险行为问卷及CES - D抑郁量表,采用多阶段整群抽样法抽取徐州市4 190名青少年进行问卷调查。结果 在控制人口学等变量后,受校园欺凌、网络成瘾、睡眠时长对抑郁均有预测作用(r = 0.283,P<0.01;r = 0.331,P<0.01;r = - 0.184,P<0.01)。路径分析表明,网络成瘾在受校园欺凌和青少年抑郁之间起中介作用;网络成瘾和睡眠时长在受校园欺凌和青少年抑郁间起链式中介作用。结论 受校园欺凌不仅直接影响青少年抑郁,还通过网络成瘾和睡眠时长的链式中介作用间接影响青少年抑郁。可通过减少青少年网络使用和提高睡眠时长来降低受校园欺凌对青少年抑郁的影响。 相似文献