Aging reverts to juvenile conditions the synaptic connectivity of cerebral cortical pyramidal shafts.

Quantitative analysis of the total number and distribution of dendritic spines along the apical shafts of layer V cerebral cortical pyramids has been performed on aging rats (90-120 to 1,135 days old) and on rats during the period of early and late development (10-80 days). As expected from previous work, present results show that the total number of dendritic spines along the shafts increase from 10 to 80 days, after which it starts to gradually decrease until the last age studied (1,135 days). The quantitative analysis of the effect of aging on the relative decrease of dendritic spines shows that this decrease starts being homogeneous along the whole length of the apical shafts and that from a certain age onwards, estimated according to present results in 400 days, this effect is significantly more pronounced in layers IV and III-II than in deep layers. Furthermore, the comparison made between the distribution of dendritic spines along the apical shafts of pyramidal neurons of old and young animals has shown that aging produces a regression of this distribution to juvenile conditions.     

The role of the posterior cricoarytenoid muscle in phonation: an electromyographic investigation in dogs

The activity of the posterior cricoarytenoid muscle during respiration has been well investigated electromyographically. Its activity during phonation, however, has not been studied systematically. We, therefore, focused our attention on the phonatory activity of the posterior cricoarytenoid muscle to confirm whether it also contracts during phonation, as has been reported by some researchers. In our series of 12 adult dogs, the posterior cricoarytenoid was active in 11 dogs and inactive in one dog during phonation. Our present study also showed that the posterior cricoarytenoid activity was stronger for phonation than for inspiration in 6, stronger for inspiration than for phonation in 3, and the same for phonation and inspiration in 2 dogs. The results obtained from the present electromyographic evaluation demonstrated that the posterior cricoarytenoid is activated during phonation. The authors believe that the posterior cricoarytenoid muscle has phonatory function and that the phonatory effect of this muscle on the vocal cord may play an important role in precise glottis control.     

双阴性选择法纯化培养人骨髓多能成体祖细胞

OBJECTIVE: To establish a method for purifying and culturing human multipotent adult progenitor cells (MAPCs) in vitro. METHODS: Mononuclear cells were separated from the bone marrow of healthy adult volunteers by density gradient centrifugation and cultivated in adherent culture. The plastic-adherent cultured bone marrow cells were isolated by magnetic-activated cell sorting with CD45 and GlyA magnetic microbeads, and the purity of CD45-/GlyA- cells evaluated by flow cytometry. Phase-contrast microscopy was used to detect morphological changes of the cells in different stages of culture. RESULTS: Approximately (5-10)x10(4)/ml MAPCs could be separated from every 1x10(6)/ml bone marrow mononuclear cells by magnetic- activated cell sorting. The viability of the cells before and after separation was (96.7+/-1.7)% and (96.0+/-2.4)%, respectively. The isolated MAPCs grew well in a self-prepared culture medium till the16th passage. The purity of CD45-/GlyA- separated from the bone marrow was more than 98% as examined by flow cytomety even till the 12th passage. CONCLUSIONS: MAPCs derived from adult human bone marrow can be purified by magnetic-activated cell sorting with CD45 and GlyA microbeads and retain the undifferentiated state for a long time. The self-prepared culture medium is appropriate for MAPCs cultures in vitro.     

双相气道内正压呼吸机在老年慢性阻塞性肺疾病康复期和急性肺水肿患者中的临床应用

应用双相气道内正压呼吸机（ＢｉＰＡＰ）对９例慢性阻塞性肺疾病（ＣＯＰＤ）康复期和呼吸衰竭稳定期进行临床观察发现，治疗后动脉血氧分压与治疗前相比显著升高（Ｐ＜０．０１）；肺活量及用力肺活量轻度升高；１例３次发生急性左心衰、急性肺水肿致急性呼衰患者治疗后，病情很快改善；１例阻塞性夜间睡眠呼吸暂停综合征者应用效果满意。该机应用简便、安全，对心率血压无明显影响，为ＣＯＰＤ康复期、急性左心衰兼肺水肿的治疗提供了新途径。     

地学与环境研究

对地学与环境科学研究之间的关系进行了描述,说明学习、掌握了地学的基本知识,才能控制和消除环境污染,改善环境质量,维护经济活动的物质基础与生态平衡.     

外伤性视神经病变的临床治疗分析

目的　探讨大剂量甲基强的松龙冲击疗法治疗外伤性视神经病变的疗效。方法　 2 0例 (2 0只眼 )外伤性视神经病变患者为治疗组 ,应用大剂量甲基强的松龙冲击治疗 ,另 2 0例 (2 0只眼 )外伤性视神经病变患者为对照组 ,使用常规剂量的地塞米松治疗。两组均同时使用高渗剂、血管扩张剂、神经营养剂及 B族维生素治疗 ,对两组病例药物治疗的结果进行总结分析。结果　治疗组经治疗后视力开始恢复的时间早于对照组 ,治疗组的总有效率为 80 % ,对照组的总有效率为 6 0 % ,治疗组的疗效优于对照组 ,且治疗越早疗效越好。两组比较具有显著的统计学差异 (P <0 .0 5 )。结论　大剂量甲基强的松龙冲击疗法治疗外伤性视神经病变疗效显著 ,治疗方便 ,是较理想的治疗方法     

雌二醇对去势前列腺癌患者LH脉冲分泌的抑制作用

３例前列腺癌施行双侧睾丸节除术后２－１２周的患，每天肌注苯甲酸雌二醇１ｍｇ，ｄ。治疗前后分别每１０ｍｉｎ采血一次，作７ｈ ＬＨ脉冲分析。结果表明，３例患平均血清ＬＨ水平分别由１７７．５８±３．２０，１３８．３０±５．８３和１４５．８８±３．８２ＩＵ／ＬＧＨＢＴＧＣ １７４．９０±７．６０，１３２．０２±５．７７和１４２．８０±３．６５ＩＵ／Ｌ（Ｐ均＜０．０１），但ＬＨ脉冲幅度和频率无明显变化（