Expression of neuron-specific enolase and olfactory marker protein in the developing olfactory mucosa of human fetuses]

OBJECTIVE: To study the expression of neuron-specific enolase (NSE) and olfactory marker protein (OMP) in the developing olfactory mucosa of human fetuses. METHOD: The expression of NSE and OMP in the olfactory mucosa of 6 human fetuses (12, 16, 20, 24, 28 and 34 weeks) was studied using the technique of immunohistochemistry. RESULTS: NSE immunological positive reactions were seen in all 6 fetal mucosa from gestational 12 (G12) to G34, with plenty of positive-stained dual-pole neuron cells. At G12, the positive cells aligned tightly, the cell bodies were localized in the lower portion of olfactory epithelium and the positive-stained area occupied upper 2/3 of fetal nasal mucosa. With the development, the positive cells gradually became multilayer, but the density and the relative area of positive-cells reduced. At G34, the positive cells were located only in upper 1/3 of nasal mucosa. OMP-positive reactions were localized in a few dual-pole neurons at G12, the number was much less than NSE-positive cells in the same fetus. With the development, the OMP-positive cells gradually increased with most of the cell bodies located in the upper portion of epithelium, but number still relatively less than the NSE-positive cells at the same age. CONCLUSION: At G12, there were lots of olfactory neuron in the olfactory mucosa and only a few olfactory neurons had became mature. With the development, the olfactory epithelial area reduced but the number of mature olfactory neurons increased. At the last trimester, fetal olfactory sensor was almost matured.     

Z-3-(2-羟基丁烯基)苯酞的合成研究

研究目的探讨苯酞类天然产物的合成方法及其生物活性。研究方法以邻苯二甲酐为底物，首先引入丁烯基，再进行烯丙位氧化，制得目标化合物。结果通过丁基锂反应，得到了具有药物活性的丁烯基苯酞，然后利用SeO2烯丙位氧化，首次合成了Z－3－（2－羟基丁烯基）苯酞。结论此合成方法原料易得，方法简便，为苯酞类化合物的合成研究提供了一个新的途径。     

某化工厂1987～2000年164例工伤事故调查分析

目的调查分析某化工厂工伤事故的分布规律及其危险因素,以便采取相应的预防干预措施。方法对1987～2000年该化工厂发生的工伤事故进行回顾性调查分析,建立数据库,并统计分析。结果 ①事故以轻伤为主,约占80.0％。②事故类别主要是灼烫烧伤和机械伤害,分别为工伤事故总数的35.8％、28.5％。③工伤伤害性质以骨折多见,约为总数的56.1％。④受伤工人的年龄分布以30～40岁段为主,约为总数的31.1％。⑤工伤事故原因中注意力不集中和违反操作规程分别为总数的43.0％,38.3％。结论12根据上述流行病学特点,采取相应的措施来减少工伤事故的发生。     

基础医学教师课堂教学质量评价

为了了解本科教师的教学质量和教学效果 ,教学专家和学生评价了 14 7位基础医学教师。结果显示 ,讲师以上职称教师的教学质量明显好于初级职称教师 (P<0 .0 5 ) ,高级职称教师教学的科学性、艺术性和思想性明显好于讲师和助教 (P<0 .0 5 )。文章还对教学中存在的问题和对策进行了讨论。     

湘西自治州1995～2002年男性劳教人员法定性病监测报告

目的 了解湘西自治州重点人群性病患消长趋势，为性病防治工作提供科学依据。方法 从1995年起，采用统一的表格，每年对湘西州劳教所新入教人员进行一次法定性病监测。结果 三种法定性病平均患病率为14．64％(4．96～26．7％)，以1995年最低，1997年最高，8年未发现HIV／AIDS，患病率以20～39岁的性跃期人群为最高，汉族患病率高于其它民族；化程度越高，患病率越低。结论 男性劳教人员作为性病患病的高危人群，是哨点监测理想的目标人群。     

A promising technique for transplantation of bone marrow-derived endothelial progenitor cells into rat heart.

OBJECTIVE: To investigate the feasibility of intracoronary application of endothelial progenitor cells and the subsequent distribution within the heart. METHODS: Endothelial progenitors cells (EPCs) cultured from rat bone marrow were identified by double-positive staining with Dil-Ac-LDL and BS1-lectin. Twenty-four hours before cell transplantation, EPCs were labeled with 5-bromo-2'-deoxyuridine (BrdU). Cells (5 x 10(5) in 250-microl medium) were injected into healthy rats, either as intracoronary application (n=11) or as intramyocardial injection (n = 6). At 15 min or 3 days posttransplantation, hearts as well as other organs (lung, liver, kidney, and spleen) were collected and processed for subsequent BrdU immunohistochemistry. The number of BrdU-positive cells per tissue area was counted. RESULTS: Compared to intramyocardial injection, intracoronary administration resulted in more than twice as much positive cells in the heart (P < .05), with no local differences within the heart. Whereas after 15 min, EPCs were equally distributed in all examined organs (except for the spleen), cells that were still present after 3 days, approximately 10%, were selectively restricted to the heart. CONCLUSIONS: Our data indicate that the intracoronary application provides a promising technique for EPC transplantation in the rat heart.     

The dependence of twitch relaxation on sodium ions and on internal Ca2+ stores in voltage clamped frog atrial fibres

Frog heart relaxation was analyzed under voltage clamp conditions as the tension decay observed after the membrane potential had been returned to its resting value. The tension decayed exponentially with a time constant of 188±3.8 ms SEM. The relaxation rate decreased with the external Na concentration. It fell to about one tenth in a Na-free solution. Increasing the intracellular Na-content by an application of veratrine also decreased the relaxation rate. Thus relaxation seems dependent on the Na gradient. The relaxation rate decreased within one second upon switching from a high to a low Na-containing solution. The relaxation rate reached a minimum before rising slightly to a new steady state value. This rebound may reflect the partial recovery of the Na gradient since a fast variation in [Na]_i follows alteration of [Na]_o. Mn and La ions also slowed relaxation. In a Na-free solution, adrenaline accelerated tension decay, an effect not noticeable in frog heart contained in Ringer solution. Other cAMP-promoting agents, such as dibutyryl-cAMP and aminophylline, also increased relaxation rate.It is concluded that in frog myocardium, part of the decrease of the intracellular Ca²⁺-concentration which occurs during each cardiac cycle could be dependent on a Na–Ca exchange mechanism. The relative importance of this mechanism, versus internal Ca sequestration, in the relaxation of tension may well be greater in contractile tissues whose cells have a large surface/volume ratio.