人窦房结和房室结微血管的扫描电镜观察

本文用4例新鲜婴儿尸体,采用血管铸型扫描电镜法,观察人窦房结、房室结微血管的立体构筑。结果表明,窦房结的血管床是由微血管网构筑成一椭圆形网状结构,中央动脉贯穿于结的长轴,由此动脉向周围发出分支,逐级分为许多微动脉和毛细血管前微动脉,最后在结的浅部分成毛细血管网。毛细血管后微静脉的收集范围,则显示出按区收集的特点。而房室结微血管构型是一扁圆形的微血管网,结的浅部为一薄层比较细密的毛细血管网。透过网眼,可见有粗大的、彼此吻合的窦状静脉丛。房室结动脉由结一侧进入结内,向周围逐级分支,形成毛细血管前微动脉,穿行于静脉丛之间,在结的浅部连于毛细血管网。毛细血管后微静脉的始端有环形缩窄,为平滑肌压痕。     

人腮腺微血管构筑

用血管铸型扫描电镜法，观察人腮腺微血管的构筑。从铸型上看，腮腺各小叶的界限分明。小叶的表层为管径粗细一致的毛细血管，它们在腺泡和闰管周围相互吻合成毛细血管网。腺泡和闰管周围毛细血管网起自腺泡微动脉。腺泡微动脉主要起自小叶内动脉，但也可起自小叶间动脉。纹状管周围为毛细血管后微静脉和微静脉相互吻合形成的网状静脉丛。小叶间导管起始部的周围，为一层由毛细血管和毛细血管后微静共同形成的微血管网，随着小叶间导     

15 人脑海马内部微血管三维构筑的研究

<正>本文采用5例有机玻璃单体铸型标本,暗视野全景观察和日立S—450扫描电镜观察,较完整地显示人脑海马内部血管从动脉—微动脉—毛细血管前括约肌—毛细血管—微静脉—小静脉连续性立体构筑。海马内微动脉与微静脉有着特殊的分布形式,本文观察到一支动脉分细支或数条动脉的分支组成血管网,数支微动脉伴随一条微静脉为-血管单位,毛细血管互相交织成不规则的血管网.皮质动脉分支走向及毛细血管袢长轴与神经纤维走向平行。皮质长、短动脉各序支管随年龄增长而变粗;皮质动脉在深部发支返回浅层。本文观察到微血管间存在多种吻合:1.微动脉间吻合;2.毛细血管前动脉间吻合;3.微动脉与微静脉间吻合;4.微静脉间有搭桥式吻合。微血管形态特征;小动脉壁有卵圆形的内皮细胞核压迹,排列整齐,清晰可见。小静脉壁有圆形的内皮细胞核压迹。较大数量的毛细血管前括约肌和微动脉末端肌纤维包绕管壁形成纹理的微动脉括约肌,微动脉管径突然变细呈锥状与毛细血管相连接。毛细血管汇入静脉,静脉属支呈“树根状”。     

胎儿和新生儿肾上腺的血管构筑

本文采用血管复型扫描电镜,注射墨汁切片光镜下观察和注射铅丹乳胶X线照像3种方法,研究了28例胎儿和新生儿肾上腺的血管构筑。发自膈下动脉、腹主动脉和肾动脉的肾上腺上、中、下动脉及其分支,在肾上腺囊表面和穿过囊的过程中逐级分支,最后形成毛细血管。动脉和毛细血管共同构成囊血管丛,从该丛发出的皮质动脉和髓质动脉,分别分支供给皮质和髓质。从囊血管丛发出的“V”型动脉在皮质中行一段距离后又返回囊中分支。永久性皮质毛细血管网是囊毛细血管的直接延续。在胎儿性皮质中,毛细血管有两个来源,其一是永久性皮质毛细血管的延伸;另一来源是由皮质动脉分支构成。它们共同构成胎儿性皮质毛细血管网。在胎儿性皮质的中部,毛细血管汇成小静脉。中央区的髓质由髓质动脉供血。在皮质中,正在迁移的髓质细胞团由与之伴行的动脉供应。在皮质中形成的小静脉呈向心性行走。其中一部分在近中央区又分为毛细血管,这些毛细血管相互吻合,最后入中央静脉的属支中。这种分布特点属于门脉形式的血管;另一部分属于中央静脉的第一级属支,它们逐级汇合后形成中央静脉主干。中央静脉系呈树枝状,其主干在腺的前面穿出腺后为肾上腺静脉。左侧肾上腺静脉人左肾静脉;右侧的人下腔静脉。而与动脉伴行的肾上腺上、中、下静脉的末级属支与囊毛细血管相连。本研究讨论了胎儿和新生儿肾上腺血管的分布规律,为胎儿内分泌学和肾上腺移植等方面提供了血管形态学基础。     

胰腺微循环通道及其临床意义：光镜和扫描电镜研究

用甲基丙烯酸甲酯微血管铸型扫描电镜观察、血管内墨汁灌注连续切片光镜观察,对20例恒河猴的胰腺微循环通道进行了研究。猴的胰腺微循环通道主要途径为:小叶间动脉→小叶内动脉→入岛血管→胰岛血窦→出岛血管(门脉)→腺泡毛细血管网→小叶内静脉→小叶间静脉。构成胰腺基本单位的胰腺小叶,其血供特点是:由独支小叶内动脉供给血液,相邻小叶内动脉及其分支之间无吻合存在,属终动脉,推测这一特点可能是急性胰腺炎小叶内灶性坏死的形态学基础。     

扫描电镜对胎儿左心室壁内微血管构筑的观察

用血管铸型结合扫描电镜方法研究了5例胎儿左心室壁内微血管构筑。在心肌中层内,较大的微动、静脉伴行,呈“层状”分布。微动脉与微静脉的关系是:微动脉两次近似直角双叶状分支,毛细血管汇集成毛细血管后微静脉或直接以直角汇入微静脉。在心外膜下层,微动脉间吻合丰富,分出毛细血管有两种形式。在心内膜下层,微动、静脉不伴行,微静脉数目多见,而微动脉较少。毛细血管间吻合复杂。本文对不同心肌层内的毛细血管口径、间距进行了测量,并讨论了胎儿左心室壁内微血管构筑特征和微循环模式。     

幼儿基底神经节微血管构筑

目的:观察幼儿基底神经节微血管构筑的形态学特点.方法:采用改良碱性磷酸酶染色法显示幼儿基底神经节的微血管形态及吻合.结果:本实验成功地显示出微静脉,且观察到微动脉和微静脉间的吻合.基底神经节各核团内的微动脉有两种类型即长微动脉和短微动脉.其走行迂曲,多为树根状、树藤状和弓状,分支以大锐角发出多见,但也可见直角和钝角发出者,经1～4级分支形成毛细血管网.基底节区内各核团和内囊微血管密度高低不等,其由高到低依次为壳核、尾状核、屏状核、杏仁核、苍白球、内囊.结论:基底神经节各核团内微动脉的走行迂曲、形态各异,可能是该区易发生出血的形态学基础.各核团间微血管密度的差异,说明各部神经细胞的需氧量和代谢的活跃程度不同.     

Lectin标记人胎视网膜血管的形态学观察

采用生物凝集素荆豆I（ectin）组化法标记人胎视网膜血管内皮细胞，以显示视网膜各级血管。观察到机网膜大血管自视神经盘处穿出向周边视网膜呈放射状分布。在视神经盘附近，大血管之间无例支交通，但它们之间存在着毛细血管网。自视网膜中部（赤道附近）地区开始，可见较小血管呈逐级典型的观分叉状分支向着周边视网膜分布。动脉血管与静脉血管在胎6月龄后的样本中已能清楚地区分；前者较后者稍细而着色稍深，两者互不伴行。微动脉与微静脉间形成的毛细血管网显示清晰。毛细血管网网眼大小不等，呈不规则的多边形。此外，还在一例样本中见到相邻两支较大血管间的样状吻合。胎6月龄以前，视网膜血管尚未分布到锯齿缘。     

国人脑动脉系统的研究——五、新生儿大脑内动脉的配布

用注射、固定透明的脑厚切片在立体解剖显微镜下观察了十一个新生儿大脑内微动脉的走行与配布。各大脑动脉在大脑表面反复分支,互相吻合,形成多角形和不规则形的软膜动脉网。各脑回内微动脉的走行和配布形象具有共同特征。皮质动脉由软膜动脉网发出,与脑表面垂直穿入大脑皮质,在皮质内是直行的,排列整齐,随沟回起伏。皮质长动脉管径为16～31微米,短的为7.5～15.4微米,形成多角形或不规则形的毛细血管网。髓质动脉从回顶穿入的完全直行,长的直达髓质深部,管径为48～61微米,短的只35～47微米。从脑沟穿入的髓质动脉在皮质内是直行的,至髓质则有不同程度的弯曲,随同纤维方向行走。髓质动脉的分支也都以直角分出,行一短程,又“T”形分叉,互相连接,构成近似长方格形的毛细血管网。中央动脉由脑底等处穿入,至纹状体的动脉在穿入脑实质以后,沿壳核浅层扇形分开,弧形上行;丘脑的动脉从后外、下内及上面各方面穿入,分支也均呈锐角,经3～4级分支后形成多角形,三角形、近圆形和不规则形毛细血管网。内囊的动脉多顺纤维方向行走,也直角分支,“T”形分叉,形成近似长方格形的毛细血管网,但杂有横行从豆状核至尾状核的分支。     

用注射复型扫描电镜方法观察足月胎儿胆囊微血管的构筑

用甲基丙烯酸甲酯铸型方法,将胎儿胆囊壁微血管制成铸型扫描电镜样品,脱水、干燥后,用EIKO IB-3型离子镀膜仪镀膜,在扫描电镜下观察。胆囊壁微血管明显分为三层,即浆膜层血管、肌层血管和粘膜层血管。其中浆膜和肌层血管与肠管壁相应层次的血管结构类似。而粘膜层血管则被分为两部分,一部分紧贴上皮细胞下,有一层丰富的毛细血管网;另一部分在固有膜内有管径粗大的静脉丛。毛细血管网与静脉丛之间直接以毛细血管相连。微动脉的数量相对较少,穿行于静脉丛之间,并逐级分支延续于毛细血管网。本文未见有动、静脉吻合。但在微动脉与静脉丛之间,常见有构成功能性毛细血管短路的毛细血管性交通支。     

The blood vascular architecture of the rat thyroid gland: a scanning electron microscope study of corrosion casts

The blood vascular bed of the rat thyroid gland was reproduced by injection of a methacrylate casting medium and observed with a scanning electron microscope. The rat thyroid gland received the superior and inferior thyroid arteries and emitted the superior and inferior thyroid veins. Anastomosis between the interlobular arteries or between the interlobular veins was frequently observed in the thyroid gland. The arteriovenous anastomosis was rarely observed between the terminal branches of the lobular arteries and veins. The thyroid blood vascular bed was divided into lobular units which consisted of basket-like capillary networks surrounding the thyroid follicles; a small lobular unit consisted of a few networks, whereas a large one of fifty or more networks. Sizes and forms of the networks varied widely in each case. However, the networks in the superficial layers of the lateral parts of the thyroid gland were typically most developed. Regardless of its size and form, each network always received a proper efferent vessel continuous with the lobular vein, though it was sometimes provided with an accessory afferent or efferent vessel. Only occasionally were the adjacent networks fused with each other or connected by transfollicular capillaries. Thus, the present data suggest that each follicular capillary network is a fairly independent functional-unit in the thyroid microcirculation. The capillaries of the network were sinusoidal in nature and sometimes protruded fine projections which indicated the neogenesis of capillaries. The blood vascular bed of the newborn rat thyroid gland was not always differentiated into basket-like capillary networks.     

Microvascular organization of human palatine tonsils

We describe the three-dimensional organization of the microvasculature of human palatine tonsils as revealed by the vascular corrosion casting/scanning electron microscope method and light microscopy of sections. The tonsillar arteries travel in the connective tissue septa and give off many branches. They further branch into arterioles which in turn enter the follicle and the interfollicular region. These arterioles, giving off capillaries en route, reach the subepithelial region where they break up into sinusoidal capillaries. The subepithelial capillary network overlying the follicle protrudes hemispherically towards the crypt, while that overlying the interfollicular region has many switch-back loops of capillaries projected towards the crypt. The subepithelial sinusoids gather into the high endothelial venules (HEVs) which, collecting capillaries in the follicle and the interfollicular region en route, course down into the interfollicular region alongside the follicle. The HEVs surround the lateral and basal surfaces of the follicle and ultimately lead into the ordinary veins in the septa. The subepithelial sinusoids seem to be involved in taking up immunoglobulins secreted by plasma cells and any other substances released by lymphocytes and/or macrophages as well as supplying the tissues with necessary oxygen and nutrients. That the HEVs are downstream to the subepithelial sinusoids suggests that some substances which are taken up into the sinusoids and transported to the postcapillary venules induce differentiation of HEVs and maintain them.     

用注射复型SEM方法研究足月胎儿小肠粘膜的微循环

本文用注射甲基丙烯酸甲酯复型扫描电镜方法,研究了足月胎儿小肠粘膜血管的立体构筑形象。绒毛毛细血管网的特征为管腔大部分呈窦状,其间夹杂有直形毛细血管;在十二指肠乳头处,胆总管壶腹口周围及壶腹粘膜的毛细血管多呈丛状,未见窦状毛细血管。绒毛的毛细血管网接受来自三方面的动脉血,即通过来自粘膜下动脉的微动脉,从绒毛顶部、基底部和腺丛的交通支,向绒毛毛细血管网供血。后者构成小肠绒毛的“门脉系统”。微动脉在绒毛顶部与微静脉有交通支,构成动静脉吻合。微静脉从顶部到基底部贯穿整个绒毛,沿途自绒毛毛细血管网及腺丛接受属支,最终注入粘膜下静脉,与Mall的典型的“喷泉型”概念并不完全一致。     

Thyrocyte integration, and thyroid folliculogenesis and tissue regeneration: Perspective for thyroid tissue engineering

The thyroid gland is composed of many ball-like structures called thyroid follicles, which are supported by the interfollicular extracellular matrix (ECM) and a capillary network. The component thyrocytes are highly integrated in their specific structural and functional polarization. In conventional monolayer and floating culture systems, thyrocytes cannot organize themselves into follicles with normal polarity. In contrast, in 3-D collagen gel culture, thyrocytes easily form stable follicles with physiological polarity. Integration of thyrocyte growth and differentiation results ultimately in thyroid folliculogenesis. This culture method and subacute thyroiditis are two promising models for addressing mechanisms of folliculogenesis, because thyroid-follicle formation actively occurs both in the culture system and at the regenerative phase of the disorder. The understanding of the mechanistic basis of folliculogenesis is prerequisite for generation of artificial thyroid tissue, which would enable a more physiological strategy to the treatment of hypothyroidism caused by various diseases and surgical processes than conventional hormone replacement therapy. We review here thyrocyte integration, and thyroid folliculogenesis and tissue regeneration. We also briefly discuss a perspective for thyroid tissue regeneration and engineering.     

The anatomy and blood system of the kidney in the river lamprey, Lampetra fluviatilis

Summary The anatomy and blood system of the kidney in the river lamprey, Lampetra fluviatilis, was studied after injecting microfil into nephrons or the arterial system. Renal arteries arose at irregular intervals from the dorsal aorta and gave rise to a regular arrangement of afferent arterioles supplying the network of glomerular capillaries. Nephron units were arranged in two longitudinal series on each side of the glomerular capillaries, with the capsule of each nephron closely related to the capillary network. A short neck segment lead into the convoluted proximal segment, which accounted for over half the length of each nephron and was surrounded by a network of capillaries and sinusoids supplied by efferent glomerular arterioles. The end of each proximal segment formed the descending limb of a nephron loop, which lay parallel to the ascending distal limb and the end of each collecting duct. Peritubular blood flow in this region was generally opposite the flow of tubular fluid and blood eventually drained into large thin-walled sinuses connected to the post-cardinal vein.This work was supported by SRC research grant number GR/A 1820.7. We thank Miss V. Griffiths for technical assistance and Mr. P. Gaskins for the supply of lampreys     

Kidney morphology in hemolytic-uremic syndrome

Morphology of the kidneys in hemolytic-uremic syndrome is considered basing on autopsy findings obtained for 3 infants with 5-17-day history of acute renal failure. A newborn infant of 17 days developed the disease after feto-fetal hemotransfusion when macerated fetus-donor hemolysis products entered the circulation of the fetus-recipient through monochorionic placenta. The second case in an infant of 6 months was due to ADTP Vaccine. The last infant aged 16 months manifested the syndrome in the presence of Proteus-induced ulcerative colitis. Varying in etiology, renal morphology exhibited similar features: fibrin deposits in the lumens of glomerular capillary loops, afferent glomerular arterioles and intrarenal arteries; fibrinoid necrosis of the wall in the arterioles. The renal affection ranged from acute thrombotic glomerulonephritis to cortical necrosis, these variations being dependent on the degree of thrombogenesis, caliber of impaired intrarenal vessels and time from the onset of acute renal failure.     

Tuft-to-capsule adhesions and their precursors: differences between the vascular and tubular poles of the human glomerulus

Human glomerular capillary tufts were removed by microdissection and scanning electron microscopy was used to examine the surface of the capillary tuft and the interior of its Bowman's capsule in order to identify connections between the tuft and capsule. Glomeruli were examined in histologically normal renal cortex from 12 kidneys removed for tumour and 12 renal allografts removed for end-stage rejection. In normal kidney, the glomerular tuft was connected to Bowman's capsule by single podocytes and their processes. At the vascular pole, these were predominantly associated with parietal podocytes which lined Bowman's capsule. At the tubular pole, occasional podocytic processes derived from the capillary tuft bridged Bowman's space and connected to Bowman's capsule where there were no parietal podocytes. These podocytic connections were also found in all rejected transplants, but in addition adhesions were identified which consisted of thicker connections between the tuft and capsule. At the vascular pole, tuft-to-capsule adhesions were found in all 12 kidneys; these were always associated with parietal podocytes. Tubular pole adhesions were identified in ten of the 12 transplants. They were associated with abnormal squamous cells, but not with parietal podocytes. When the capillary tuft herniated into the proximal tubule, the tuft sometimes formed an adhesion with the origin of the proximal tubule. These observations suggest that podocyte connections between the glomerular tuft and Bowman's capsule may be precursors of glomerular adhesions at the vascular pole. Since tuft-to-capsule adhesions at the vascular pole differ morphologically from those at the tubular pole, this may reflect different pathogenetic mechanisms at the opposite poles of the glomerulus. © 1998 John Wiley & Sons, Ltd.