小鼠睾丸发育全过程中生精细胞的自发性凋亡

 以17组出生后不同发育阶段的昆明种正常小鼠睾丸组织为材料,采用TDT原位末端标记法在其石蜡组织切片上进行凋亡细胞原位检测,探讨小鼠睾丸发育全过程中生精细胞的自发性凋亡规律.结果发现:小鼠生精细胞从生后开始就存在自发性凋亡现象,生后1~15 d,凋亡精原细胞数目不断增加;至生后第15天时达到峰值,且15 d起个别初级精母细胞也开始出现凋亡;至27 d时,极少数次级精母细胞和精子细胞出现凋亡;至30 d时凋亡细胞基本为精原细胞;而33 d时各类型生精细胞均存在凋亡现象;至36 d时凋亡细胞又重新集中于精原细胞,并延续于此后各期.上述结果表明:小鼠睾丸发育过程中凋亡细胞主要为精原细胞;自发性凋亡活跃期发生于生后1~33 d,与生精细胞的首次发育成熟过程同步.     

婴儿早教对德语教学的启示

婴儿早期教育尤其是语言早教理念和方法对外语实践运用能力培养具有良好的指导和借鉴作用。本人已非德语专业学生作为对象,重点研究婴儿早教尤其是语言早教方法在德语培训中的应用,探讨德语教学中提高学生语言综合能力的新方法、新途径。     

大师的机会

意大利著名男高音歌唱家帕瓦罗蒂在成名前经常四处巡回演唱。有一天夜晚,他在一间小旅馆里正准备就寝,隔壁却传来小孩的哭闹声,一哭就是三四个小时,搅得他不胜其烦。想到第二天还要赶场子,帕瓦罗蒂非常生气,准备去隔壁房间提醒一下。可是他刚走到隔壁门口,抬起手正     

拥挤的诺亚方舟——从第70亿个婴儿的诞生说起

根据联合国有关组织的测算,在2011年10月31日的某一时刻,地球上第70亿个婴儿诞生在菲律宾。这一刻,地球人口达到了70亿。12年前的1999年,世界上第60亿个婴儿才刚刚出生。地球围着太阳匆匆转了12圈,转眼间,地球人口就增长了十个亿。人口的增长是多么地迅速啊!     

婴儿看世界

悬在摇篮上方的彩色玩具缓缓地旋转，摇篮里的宝宝却睁着圆鼓鼓的眼睛凝视着这场永无赢家的比赛，仿佛想要洞悉世间最深的奥秘…此时，小家伙究竟在想些什么？十多年前，许多心理学家仍认为这些举动毫无意义。在他们看来，婴儿只能意识到“当时当地”，除了通过感官感觉这个世界外，不具备任何其他认知能力。而且，3岁以下幼儿在游戏中的表现，也无不说明他们尚不具备区分现实与虚幻、合理与荒谬的能力。     

总熵判据的作用和局限

首先讨论了环境熵变和热源熵变间的区别，以及两者相同时的条件；然后阐述了总熵判据和克劳修斯不等式在本质上并无不同之处，都可以用于判别过程的可逆性；最后将总熵变与隔离体系的熵变相比较，对它们的用途进行了详细讨论。     

Change in the body temperature of healthy term infant over the first 72 hours of life

OBJECTIVE: To determine the range of body temperature in a group of healthy Chinese term neonates over the first 72 hours of life and to assess the influence of body weight, gestational age and route of delivery.METHOD: All 200 consecutive cases of neonates delivered at our hospital from March to August 2001 were included in this retrospective study. Temperatures were measured immediately after delivery, after 30 minutes, 1 hour, 2 hours, 8 hours and 15 hours and on the 2nd and 3rd day. Axillary temperatures ranging from 36.5 degrees C to 37 degrees C were regarded as normal. No cases of maternal fever or systemic infection of the newborns were discovered. All infants were discharged in good general condition. RESULTS: The mean rectal temperature at birth was 37.19 degrees C. The lowest average temperature was reached at 1 hour after delivery (36.54 degrees C) with a significant difference between natural delivery (36.48 degrees C) and section (36.59 degrees C) (P<0.05). Temperature subsequently rose to 36.70 degrees C at 8 hours and 36.78 degrees C at 15 hours (P<0.05). Hypothermia was seen in 51.8% and hypothermia in 42.5% of the patients. On the 3rd day after delivery, 96% of all temperatures were in the normal range. A significant relation was found between hypothermia and both low birth weight (P<0.001) and low gestational age (P<0.05). CONCLUSION: The reference range presently used did not include all physiological temperatures in the first 72 hours of life. Considering other factors, such as birth weight, route of delivery, gestational age and body temperature on the 2nd and 3rd day of life, may help to correctly assess the significance of temperatures beyond the reference range.     

复发性自发性气胸的外科治疗

目的：总结复发性自发性气胸的外科治疗经验。方法：回顾性分析经外科手术治疗18例复发性自发性气胸。结果：18例手术后患肺均复张治愈。结论：复发性自发性气胸采取手术治疗,疗效确切,复发率极低。     

社区家庭婴儿抚触的方法指导

本文从婴儿抚触对母亲和宝宝的益处以及在社区家庭中实施的方法和注意事项进行指导。