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关键词： 医学生   基础课程   临床课程   相关因素   人体解剖学   组织胚胎学   生物化学   教学模式   教学方法  

摘要： 为了探讨医学生基础课程与临床课程成绩的相关因素影响 ,随机抽查某校临床医学本科 97、98及 99年级三个年级各5个班基础课程的人体解剖学、组织胚胎学、生物化学、生理学 ,临床课程的内科学、外科学、妇产科学、儿科学等课程的考试成绩进行了统计学分析。结果显示 ,基础课程的平均成绩为 69.6,而临床课程的平均成绩是 78.3 ,经统计学分析差别具有显著性意义 ( P<0 .0 5 )。

关键词： Endothelium   Vascular   Fetal Anoxia   Fetal Growth Retardation   Protein-Energy Malnutrition   内皮   血管   胎儿缺氧   胎儿生长迟缓   蛋白质能量营养不足   Femoral Artery   Hypoxia   Protein-Energy Malnutrition   Arteries   Fetal Anoxia   Fetal Growth Retardation   Chronic exposure   Acetylcholine   Kwashiorkor   Growth Retardation   Protein Deficiency   Endothelium  

摘要： Deviations in the rate of intrauterine growth may change organ system development, resulting in cardiovascular disease in adult life. Arterial endothelial dysfunction often plays an important role in these diseases. The effects of two interventions that reduce fetal growth, chronic hypoxia and protein malnutrition, on arterial endothelial function were investigated. Eggs of White Leghorn chickens were incubated either in room air or in 15% O-2 from d 6 until d 19 of the 21-d incubation. Protein malnutrition was induced by removal of 10% of the total albumen content at d 0. In vitro reactivity of the femoral artery in response to vasodilators was measured at d 19. Both chronic hypoxia and protein malnutrition reduced embryonic body weight at d 19 by 14% without affecting relative brain weight. Chronic hypoxia or protein malnutrition did not change sensitivity to the exogenous nitric oxide donor, sodium nitroprusside (5.74 +/- 0.15 versus 5.85 +/- 0.23 and 6.05 +/- 0.18 versus 6.01 +/- 0.34, respectively). Whereas protein malnutrition did not modify arterial sensitivity to acetylcholine (7.00 +/- 0.10 versus 7.12 +/- 0.05), chronic hypoxia reduced sensitivity to this endothelium-dependent vasodilator (6.57 +/- 0.07 versus 7.02 +/- 0.06). In the presence of Nomega-nitro-L-arginine methyl ester, this difference in sensitivity to acetylcholine was no longer apparent (6.31 +/- 0.13 versus 6.27 +/- 0.06), indicating that chronic exposure to hypoxia reduced sensitivity to acetylcholine by lowering nitric oxide release. In additional experiments, a decrease in basal nitric oxide release in arteries of 3- to 4-wk-old chickens that had been exposed to in ovo chronic hypoxia was observed (increase in K+ contraction: -0.16 +/- 0.33 N/m versus 0.68 +/- 020 N/m). Protein malnutrition and chronic hypoxia both induce disproportionate growth retardation, but only the latter impairs arterial endothelial function. Intrauterine exposure to chronic hypoxia induces changes in arterial end

ISBN: (纸本)7810714228

关键词： chicken   19-nortestosterone   bursectomy   reproductive hormones   adrenal   gonad   histology of gonads  

摘要： Four-day-old chick embryos were hormonally treated with 19-nortestosterone in order to inhibit bursa development. At days 1, 4, 8, 15, 22, 29, and 36 of age, plasma, adrenals, and gonads from intact and hormonal treated chicks were collected. In embryonic nortestosterone treated males the appearance of a left 'ovotestis-like' gonad was observed. The occurrence of this ovotestis-like left gonad in the 19-nortestosterone treated male is probably a secondary effect of the in ovo treatment since surgically bursectomised chicks did not show the testicular morphology and histological changes as observed in 19-nortestosterone treated chicks. Additionally, both male and female hormonally or surgically treated chicks showed relatively enlarged adrenal glands. Hormonal bursectomy affected organ inhibin contents and plasma inhibin, testosterone, and FSH levels in males. Male hormonal treated chicks showed lower levels of plasma inhibin (p = 0.0001), testosterone (p = 0.01), and FSH (p = 0.004), and a lower total testes inhibin content (p = 0.0003) compared to intact chicks. However, none of these were significantly different between female intact and hormonal treated chicks, again indicating that the observed hormonal changes in males are not the result of the disappearance of the bursa but of the hormonal 19-NT treatment. The total adrenal inhibin content as well as the adrenal inhibin concentration were significantly higher in hormonally treated chicks than in intact chicks (p = 0.0001), regardless of the sex. (C) 2003 Elsevier Science (USA). All rights reserved.

关键词： Carbonic-anhydrase   Camp   Expression   Erythrocytes   Membrane   Anaerobic conditions   membrane   Hematocrit   Chick Embryo   Oxygen affinity   Carbonic Anhydrases   Adrenergic beta-Receptors   Hormones   Cell Physiological Phenomena   Erythrocytes   Cyclic AMP   camp  

摘要： The red blood cell function of avian embryos is regulated by cAMP. Adenosine A(2A) and beta-adrenergic receptor activation during hypoxic conditions cause changes in the hemoglobin oxygen affinity and CO2 transport. Furthermore, experimental evidence suggests a general involvement of cAMP in terminal differentiation of avian erythroblasts.

关键词： Animals   Cell Differentiation   Cells   Cultured   Flow Cytometry   Histidine Decarboxylase   Histocytochemistry   Mice   Receptors   Histamine H1   Reverse Transcriptase Polymerase Chain Reaction   Stem Cells   Thymidine  

关键词： barley   mature embryo   plant regeneration   thidiazuron  

摘要： The in vitro plant regeneration frequencies for immature scutella, leaf-bases/apical meristems (LB/AM) and mature embryos of four commercially important barley genotypes were compared. Production of shoots from mature embryos or calluses of LB/AM incubated on media containing 1.0 or 2.0 mg l(-1) 6-benzylaminopurine (BA) were comparable to regeneration frequencies obtained for scutella-derived calluses of the same genotypes. Incubation of excised mature embryos and LB/AM on media containing the plant growth regulator, thidiazuron (TDZ), resulted in an increased shoot production. However, TDZ treatment did not stimulate plant regeneration from calluses derived from scutella or LB/AM. Shoots formed from TDZ-treated mature embryos and LB/AM were induced without a callus interphase and the in vitro culture system gave a three- to eight-fold higher regeneration frequency than recorded for scutella-derived calluses on BA medium. The simplicity and rapid development of shoots using the mature embryo system could potentially be used for the regeneration and genetic transformation of barley over alternative regeneration systems.

关键词： 组织胚胎学   实验课   绘图技能   技能训练   教学改革  

摘要： 实验课是理论联系实际的重要途径,是理论的深入、扩展和补充,与理论课讲授具有同等重要的地位,其目的和任务是使学生获得基本技能的训练.而组织胚胎学是一门形态学学科,其特征就是要在显微镜下观察细胞,组织和器官的形态结构.对于形态的描述最有效,其基本的技能训练之一就是绘图.通过十多年的教学实践,深感培养学生实验课绘图技能的重要,下面就谈一些自己的体会.

关键词： 人体生物节律   组织学   胚胎学   教学   教学方法   朦胧-清醒节律   日节律   昼夜节律   授课时间   课程设置  

摘要： 在组织学与胚胎学的教学中如何让学生兴奋起来,并且理解和记忆每节课的知识点是每个教师所关心的问题.多少年来教育工作者们八仙过海各显神通,想尽一切办法在研究教学方式方法上做了大量的工作.但是能够运用人体生物节律的理论去研究教学方法的报道还很少.本文从对人体生物节律的认识角度,探讨如何改进组织学与胚胎学的教学方法,以提高教学质量.

关键词： 胚胎   转移生长因子-β   免疫组化   增殖分化  

摘要： 目的　研究转移生长因子 β(TransformGrowthFactor,TGF β)在胚胎的肝、脑室、和脊髓等组织器官中增殖和分化中的作用。方法　用 5 1天的人胚胎行免疫细胞化学ABC法染色。结果　在胚胎第 5 1天 ,肝、脑室、和脊髓等组织器官中均有TGF β阳性细胞存在 ,不同器官其阳性细胞的数量、反应强弱和表达情况有差异。结论TGF B在人胚胎发育过程中 ,对肝。