国人胎儿卵巢组织发生的形态学观察

在16～38周41例胎儿中,取右侧卵巢固定于Bouin液中,制成切片,HE染色,在显微镜下观察了卵巢的发育过程。见到卵巢表面上皮随胎龄变化而发生变化;20周胎儿卵巢出现白膜,到36周时发育完整;16周时在卵巢皮质和髓质交界区出现原始卵泡,20周后大量原始卵泡存在于皮质中且可观察到少数生长卵泡;36周时生长卵泡出现卵泡腔。     

胎儿肾上腺的研究

本文观测了河南地区１９８例胎儿肾上腺。肾上腺重（ｙ）与体重、胎龄分别有很好的直线、指数曲线回归关系，回归方程为和；１５周胎肾上腺皮、髓质分明，皮质分化出球状、束状和网状三带，以后的发育中皮质所占比例变小，皮质中网状带渐薄，束状带渐厚。     

人胎儿小脑皮质蒲肯野细胞发育的定量观察

本文应用体视学方法，对３５例不同月龄组的胎儿，观察其小脑皮质蒲肯野细胞在发育过程中的变化．结果发现蒲肯野细胞层在胚胎第６个月时出现，其数密度和核体密度随月龄的增长逐渐减少，细胞的体积则随月龄的增长而逐渐增大．体密度与表面积密度变化不明显．     

187例胎儿肾脏的研究

收集河南地区15～40周胎儿187例。测其体重和肾重,结果表明:二者有显著的正相关关系,相关系数为0.9966,回归方程=0.4958+0.0030x(x-体重);肾重随胎龄(x)变化的回归方程为=0.1959e~(0.4003x)。各龄部分肾脏按常规石蜡切片,光镜观察结果:15周胎肾小体、肾小管数目较少,间质丰富;皮、髓质分明,由皮质浅层至深层肾小体体积渐增大、结构渐成熟。肾小体和肾小管数目于16～32周迅速增加。24周后部分肾小体血管球呈分叶状,一般2～4叶。26周后皮质中有典型的髓放线和迷路相间排列。致密班见于24周以后。     

大熊猫（Ailuropoda Melanoleuca）卵巢的年龄变化

对比观察了5只不同年龄大熊猫(包括青年、中年和老年)的卵巢皮质石蜡切片。可见皮质结构有较大的年龄变化。主要表现在:性成熟后,卵巢皮质的厚度随年龄的增长有减薄的趋势。成年的各级正常卵泡数量较少,初级和次级的更少;闭锁卵饱和间质腺较多,并呈现出随年龄增长而增多的动向。老年卵巢结构变化明显,皮质纤维化,卵泡全部消失,仅有较多囊泡,小动脉管壁增厚,管腔变小。老年卵巢的外形、体积和重量等方面与成年之间未见明显年龄变化。     

川芎嗪抑制蟾蜍离体嗜铬细胞分泌的实验研究

目的　研究川芎嗪 (TMP)对由乙酰胆碱 (ACh)或高K+ 引起的离体蟾蜍肾上腺髓质嗜铬细胞儿茶酚胺分泌的抑制作用。方法　用胶原酶 ( 0 5mg/mL)消化蟾蜍肾上腺 ,再用牛血清白蛋白 ( 5mg/mL)终止消化 ,获得离体的蟾蜍肾上腺髓质嗜铬细胞。用乙酰胆碱 ( 2 0 0 μmol L)、高K+ ( 6 5mmol L)、川芎嗪 ( 0 5× 10 - 6 ～ 2× 10 - 6 mmol L)或它们的混合液分别作用于离体嗜铬细胞 ,测定其儿茶酚胺 (CA)的分泌量。结果　川芎嗪对乙酰胆碱或高K+ 引起的分泌活性均有明显的抑制作用。结论　离体蟾蜍肾上腺髓质嗜铬细胞可作为刺激_分泌耦联的模型 ;川芎嗪可能是一种钙离子拮抗剂     

人视皮质(17区)Ⅰ层胎儿期的形态发育——扫描电镜观察

14例人工流产死亡人胎,胎龄13—32周、坐高83—330mm 用于这一研究。在距状沟区作冠状断面观察。胎龄13—16周,Ⅰ层的基本成分是 Caial-Retzius 神经元,这些神经元在胎龄17周时生长和分化活跃,形态上有明显差异,胞体形态不规则,细胞间的距离增大。Ⅰ层的纤维成分随胎龄增长逐渐增多。但是,在胎龄17周,Ⅰ层内偶见有清变的尖树突,它们呈现崩解和球状膨大。此外,神经胶质细胞在胎龄13周时已发现,它们形成原始的髓鞘,包裹神经细胞体及其突起。轴体和轴树接触在本文最早胎龄组(13周)已出现,在Ⅰ层的纤维网织内已有少数轴树和轴体突触存在。在21—23周胎龄,Ⅰ层已发育很好,所有基本成分已具备,但此时皮质板上半部仍未分化。胎龄26—32周,Ⅰ层呈明显纤维网织板,形态特点是纤维成分多,细胞成分少。     

人胎儿皮肤肥大细胞发育的定量研究

本文应用体视学方法，对海口地区３５例不同胎龄的人工引产胎儿及死胎皮肤标本进行肥大细胞定量研究，结果显示胎儿真皮中肥大细胞的体密度（Ｖｖ）和数密度（Ｎｖ）随着胎儿的发育而增加，体密度的变化较数密度变化明显．     

正常胎儿心肌细胞的电镜观察

目的：研究胎儿心肌细胞超微结构特征及与成年人心肌细胞超微结构的区别。方法：选择水囊引产的正常胎儿,取心室肌组织经固定包埋后制成超薄切片,电镜下进行观察。结果：胎儿心肌细胞超微结构与成年人相比较有区别,并随胎龄不同结构上也有一定差别。结论：随胎龄的不断增长,其心肌细胞逐渐发育完善,接近成年人的心肌细胞。     

CT靶扫描在肾上腺疾病诊断中的价值

目的：评价CT薄层靶扫描在肾上腺疾病定位与定性诊断中的作用。方法：回顾性分析了55例病人56处经手术病理证实的肾上腺病变的CT影像资料,重点分析其形态、大小、密度及边缘情况。CT检查均为平扫与增强及薄层靶扫描。结果：肾上腺增生22例,CT表现主要为体积增大,其中髓质增生14例,肾上腺皮质增生8例,两者在形态及大小的CT表现无差别;肾上腺皮质增生中结节性增生4例,增强扫描后均为轻度强化;肾上腺皮质腺瘤14例,增强扫描后,轻度强化5例,中等强化7例,明显强化2例。34例肾上腺肿瘤性疾病的CT影像诊断符合率为77．14％。在定性诊断中,CT诊断与病理结果相一致有39例,误诊17例。结论：CT靶扫描在肾上腺疾病的定位及定性诊断中具有很高的价值。CT对大多数的肾上腺肿瘤性疾病诊断较为敏感;对于肾上腺髓质增生与皮质增生的鉴别,则没有明显的特异性;肾上腺皮质腺瘤可与皮质结节性增生鉴别。     

Recruitment of cytosolic proteins to a secretory granule membrane depends on Ca2+-calmodulin

An increase in free calcium triggers catecholamine secretion from chromaffin cells and calmodulin is strongly implicated as the intracellular Ca2+ receptor. In our recent studies of calmodulin action in the chromaffin cell, micromolar Ca2+ concentrations resulted in calmodulin and cytosolic proteins becoming bound to the chromaffin granule membranes. We now report that calmodulin is bound with high affinity to granule membrane proteins of molecular weights (Mrs) 25,000 and 22,000 (25K and 22K) at low Ca2+ (less than 10(-8) M) and to proteins with Mrs 69K and 50K at high Ca2+ (greater than 1 microM). Other cytosolic components (Mrs 70K, 36K, 34K and 32K) require calmodulin for their interfraction with membrane. These proteins separately bound to calmodulin-Sepharose at high Ca2+ concentrations. Although the functions of these adrenal proteins have not been established, the 34K and 32K Mr components co-migrate with clathrin light chains isolated from medullary coated vesicles and the Mr 34K components from both sources share the same one-dimensional peptide map. These interactions were observed at micromolar Ca2+ levels at 'intracellular' conditions of pH and ionic strength and would be expected to occur during secretion from the chromaffin cell.     

Intracellularly injected tetanus toxin inhibits exocytosis in bovine adrenal chromaffin cells

The clostridial neurotoxins tetanus and botulinum toxin type A are known to block transmitter release from nerve terminals, probably by interfering with some essential process controlling exocytosis after the entry of Ca2+ ions. Although exocytosis occurs in many secretory cells, these toxins show a high specificity for neurones and the secretory response of cultured bovine adrenal medullary cells is not inhibited by exposure to medium containing tetanus or botulinum toxin type A (although it is by botulinum toxin type D). Here we report that when tetanus toxin and botulinum neurotoxin type A are injected intracellularly into chromaffin cells they strongly inhibit secretion, as revealed by the measurement of cell capacitance. These results indicate that these toxins are normally ineffective in chromaffin cells because they are not bound and internalized, so do not reach their site of action. Furthermore, we have localized the secretion-blocking effects of the toxin to a fragment comprising the light chain covalently linked to part of the heavy chain, suggesting that this part of the molecule contains the active site.     

Identification of a secretory granule-binding protein as caldesmon

Stimulation of adrenal chromaffin cells results in a rise in the concentration of intracellular free calcium which initiates catecholamine secretion by exocytosis. An understanding of the molecular basis of exocytosis will require knowledge of the sites of action of calcium. A role for calmodulin has been implicated in secretion from chromaffin cells, and isolated granule membranes bind both calmodulin and a series of cytosolic proteins in a calcium-dependent fashion. Here, we demonstrate that one of the cytosolic granule-binding proteins with a relative molecular mass (Mr) of 70,000 (70K) is a form of the calmodulin-regulated actin-binding protein caldesmon, first isolated from smooth muscle. Cytoplasmic gels assembled from an adrenal medullary extract in the absence of Ca2+ contained actin and the 70K protein. The association of both of these proteins with the cytoplasmic gel was inhibited by a micromolar concentration of Ca2+. In addition, we have demonstrated that the 70K protein is localized at the periphery of chromaffin cells. These results are consistent with the notion that 70K protein (caldesmon) has a role in regulating the organization of actin filaments of the cell periphery during the secretory process.     

A role for calpactin in calcium-dependent exocytosis in adrenal chromaffin cells

Stimulation of bovine adrenal chromaffin cells results in a rise in the concentration of cytosolic calcium which triggers the release of catecholamines by exocytosis. Several cytosolic proteins that bind to secretory granule membranes in a calcium-dependent manner have been implicated in exocytosis and some belong to a family of calcium-binding proteins, the annexins. One of these, calpactin, is a tetramer consisting of two heavy and two light chains (relative molecular masses 36,000 and 10,000 respectively) and can aggregate and fuse membranes in vitro in the presence of arachidonic acid. Calpactin is found at the cell periphery and is phosphorylated when chromaffin cells are stimulated. We show here that both calpactin and calpactin heavy chain (p36) reconstitute secretion in permeabilized chromaffin cells in which secretion has been reduced as a result of leakage of cellular components. This effect is inhibited by an affinity-purified antibody against p36. Secretion from permeabilized cells is inhibited by a synthetic annexin-consensus peptide, but not by a nonspecific hydrophobic peptide; this inhibition is reversed by p36. Our results indicate that either calpactin or p36 is essential for exocytosis.     

胎肺的光镜和扫描电镜观察

68例受精龄18-32周胎肺制成光镜和扫描电镜标本,进行肺组织发生的观察。结果显示:18周胎肺属腺状期,其发育类似外分泌腺。以支气管树发育为主,其终末类似腺泡。细支气管上皮由纤毛细胞、无纤毛细胞和分泌细胞构成。22周肺属小管期,以呼吸部发育为主。呼吸性支气管、原始肺泡出现。28周肺属原始肺泡期,以大量肺泡发育为主。肺泡表面有粗细不一的微绒毛。间质中布满交织成网的纤维。     

Thymus medulla consisting of epithelial islets each derived from a single progenitor.

The thymus is organized into medullary and cortical zones that support distinct stages of T-cell development. The formation of medulla and cortex compartments is thought to occur through invagination of an endodermal epithelial sheet into an ectodermal one at the third pharyngeal pouch and cleft, respectively. Epithelial stem/progenitor cells have been proposed to be involved in thymus development, but evidence for their existence has been elusive. We have constructed chimaeric mice by injecting embryonic stem (ES) cells into blastocysts using ES cells and blastocysts differing in their major histocompatibility complex (MHC) type. Here we show that the MHC class-II-positive medullary epithelium in these chimaeras is composed of cell clusters, most of which derive from either embryonic stem cell or blastocyst, but not mixed, origin. Thus, the medulla comprises individual epithelial 'islets' each arising from a single progenitor. One thymic lobe has about 300 medullary areas that originate from as few as 900 progenitors. Islet formation can be recapitulated after implantation of 'reaggregated fetal thymic organs' into mice, which shows that medullary 'stem' cells retain their potential until at least day 16.5 in fetal development. Thus, medulla-cortex compartmentalization is established by formation of medullary islets from single progenitors.     

Nerve growth factor is a mitogen for cultured chromaffin cells

Nerve growth factor (NGF) is essential for the survival and differentiation of a number of neural crest derivatives, including sympathetic and sensory neurones. While early studies suggested that NGF might also have a mitogenic effect on these neurones, subsequent work has favoured the interpretation that NGF promotes cell survival or differentiation rather than proliferation. We have addressed the issue of a mitogenic effect of NGF using adrenal chromaffin cells, which are endocrine cells derived from the neural crest, and are closely related to sympathetic neurones. Adrenal chromaffin cells respond to NGF in vitro by expressing neuronal traits. We now report that NGF elicits a mitotic response in cultured chromaffin cells from young rats, and that this response is blocked by an antiserum to 2.5S NGF. The chromaffin cells that divided in response to NGF can subsequently become neuronal in the continued presence of NGF.     

Aggregation of chromaffin granules by calpactin at micromolar levels of calcium

Several cytosolic proteins bind to secretory granule membranes in a Ca2+-dependent manner and thus may be involved in the mediation of membrane interactions during exocytosis. One of these proteins, calpactin, is a tetramer consisting of two heavy chains of relative molecular mass (Mr) 36K (p36) and two light chains of 10K (p10). We report here that calpactin promotes the Ca2+-dependent aggregation and fatty acid-dependent fusion of chromaffin granule membranes at a level of Ca2+ that is lower than that reported for other granule-aggregating proteins, and which parallels the Ca2+ requirement for secretion from permeabilized chromaffin cells. We found subunits of calpactin to be inactive in promoting granule aggregation. Two distinct 33K proteolytic fragments of p36, differing at their N termini, also promote granule aggregation but with different Ca2+ sensitivities from calpactin. These differences suggest that the N-terminal portion of p36 modulates the Ca2+/lipid binding sites in the core portion of p36 (ref.5).