新生儿尾状核中血脑屏障超微结构与临床意义

三例新生儿和三例胎儿尾状核的血脑屏障超微结构无明显差异。它们的毛细血管内皮有胞饮泡；内皮有无隔膜的孔，内皮连接较短而直。内皮可有连续完整的基膜，厚约４０－５０ｎｍ，但也有的内皮无连续基膜，只见到絮状，电子密度低的基膜样物质。     

多层螺旋CT灌注成像对脑肿瘤瘤周水肿的临床应用

目的探讨瘤周水肿的多层螺旋cT灌注成像（CTPI）在脑肿瘤诊断方面的应用价值。方法采用Sensation16层螺旋CT机对本院29例脑肿瘤患者（胶质瘤14例，转移瘤7例，脑膜瘤8例）行CTPI，分别测量不同瘤周水肿区以及对侧正常脑组织的脑血流量（CBF）、脑血容量（CBV）、肿瘤表面渗透性（PS）、对比剂峰值时间（timetopeak，TIP，并进行比较。结果转移瘤和脑膜瘤瘤周水肿的CBV、CBF显著低于对侧正常脑组织（P〈0．05），PS差异则无统计学意义（P〉0．05）。与对侧正常脑组织比较，胶质瘤瘤周水肿的CBV差异无统计学意义（P〉0．05），而PS明显升高（P〈0．05），CBF降低（P〈0．05）。胶质瘤、转移瘤及脑膜瘤3者瘤周水肿的TTP值均较对侧正常脑组织显著延长（P〈0．05）。结论脑肿瘤的CTPI检查能定量反映瘤周水肿区的血流动力学状况，对脑肿瘤的鉴别和预测预后有重要临床意义。     

癫痫大鼠血脑屏障超微结构改变及妥泰的保护作用

目的观察马桑内酯致痫及妥泰干扰大鼠中央前回血脑屏障的超微结构改变,探讨癫痫发作及妥泰治疗机制中血脑屏障的意义。方法成年健康雄性SD大鼠30只,随机分为对照组、癫痫组、治疗组;癫痫组、治疗组用马桑内酯注入到大鼠侧脑室,制作癫痫动物模型;实验组用妥泰在癫痫发作后1h灌胃,持续7d,1次/d;7d后取大鼠大脑中央前回,做超薄切片,电镜观察中央前回血脑屏障的超微结构改变。结果癫痫组内皮细胞、基膜、周细胞出现明显水肿,电子密度降低;治疗组水肿缓解。血脑屏障内皮细胞胞质厚度、基膜厚度、周细胞胞质厚度的比较表明,癫痫组与对照组也有显著性差异(P<0.05);治疗组与癫痫组比较,有显著性差异(P<0.05)。结论1.马桑内酯致痫大鼠血脑屏障内皮、基膜、周细胞出现明显水肿,妥泰使水肿缓解;2.血脑屏障超微结构改变可能是癫痫发作及恢复的重要机制。     

早产儿脑室出血发病机理研究

早产儿脑室出血(IVH)发病早和死亡率高，幸存者可发生严重的后遗症，成为影响预后的主要问题。其发病机理包括血管内因素，血管外因素和血管因素．而脑室周围毛细血管不成熟是IVH的主要原因。本文电镜下观察了14例早产儿和1例儿童侧脑室脉络丛毛细血管内皮，发现胎儿期的内皮无基膜．完整的基膜应在出生后才逐渐发育成熟；冷冻复型标本证实内皮细胞间存在着简单的紧密连接，并随着胎儿发育而成熟。侧脑室脉络丛毛细血管内皮的超微结构特点在早产儿IVH发病中起重要作用。     

蛋白多糖在大鼠小肠集合淋巴小结高内皮微静脉中的分布

目的 研究蛋白多糖(PG)在大鼠小肠集合淋巴小结高内皮微静脉(HEVs)中的分布，探讨PG对淋巴细胞归巢的调节作用。方法 阳性胶体铁染色-酶连续阻断法，光镜和电镜观察PG在HEVs内的淋巴细胞、内皮细胞、基膜上的分布。结果 HEVs的基膜和邻接基膜的淋巴细胞的细胞膜呈强阳性着色，能被透明质酸酶、肝素酶、硫酸软骨素酶ABC阻断；电镜显示，胶体颗粒主要排列于基膜的内、外侧及穿越基膜的淋巴细胞的细胞膜上，内皮细胞、穿内皮细胞的淋巴细胞和腔内的淋巴细胞不着色。结论 分布在HEVs的基膜和穿基膜的淋巴细胞的细胞膜上的PG，主要是硫酸乙酰肝素蛋白多糖、硫酸软骨素蛋白多糖和透明质酸，可能与归巢淋巴细胞穿越基膜密切相关。     

多层螺旋CT灌注成像对脑肿瘤瘤周水肿的临床应用

目的 探讨瘤周水肿的多层螺旋CT灌注成像(CTPI)在脑肿瘤诊断方面的应用价值.方法 采用Sensation 16层螺旋CT机对本院29例脑肿瘤患者(胶质瘤14例,转移瘤7例,脑膜瘤8例)行CTPI,分别测量不同瘤周水肿区以及对侧正常脑组织的脑血流量(CBF)、脑血容量(CBV)、肿瘤表面渗透性(PS)、对比剂峰值时间(time to peak,TTP),并进行比较.结果 转移瘤和脑膜瘤瘤周水肿的CBV、CBF显著低于对侧正常脑组织(P＜0.05),PS差异则无统计学意义(P＞0.05).与对侧正常脑组织比较,胶质瘤瘤周水肿的CBV差异无统计学意义(P＞0.05),而PS明显升高(P＜0.05),CBF降低(P＜0.05).胶质瘤、转移瘤及脑膜瘤3者瘤周水肿的TTP甲值均较对侧正常脑组织显著延长(P＜0.05).结论 脑肿瘤的CTPI检查能定量反映瘤周水肿区的血流动力学状况,对脑肿瘤的鉴别和预测预后有重要临床意义.     

布依族胎儿副睾与输精管组织学观察

本文收集15～38周24例布依族正常胎儿,副睾、输精管carnoy液固定,石蜡包埋,分别采用HE染色和Me-manun PAS反应显示糖元等多糖类.结果显示:副睾16周时,管壁上皮为假复层柱状,游离面有纤毛,上皮细胞胞质中含较多粗大PAS阳性颗粒,尤以基部为甚,纤毛及基膜均呈PAS阳性反应,上皮外有大量间充质细胞,此时可据管腔位置、大小、壁厚薄区分输出小管和副睾管.随着胎龄增加,管腔渐增大,上皮变高,壁增厚,上皮细胞内PAS阳性颗粒由早期较多渐至减少,上皮基膜、纤毛,血管内皮基膜均一直呈PAS阳性反应,经淀粉酶消化1小时后仍为阳性.28周头段输出小管呈明显花瓣样、副睾管管腔圆整、上皮外形成环行平滑肌.输精管15周时,粘膜上皮为单层柱状,上皮周围见大量间充质细胞,平滑肌不明显,至19周时,上皮渐呈假复层柱状,未见纤毛,固有层结缔组     

脑肿瘤瘤周水肿研究进展

脑肿瘤瘤周水肿 ( PTBE)常引起颅内压增高 ,有时导致脑疝 ,严重威胁患者生命 〔1〕。近年来 ,有关脑肿瘤瘤周水肿研究取得了很大进展 ,现代影像技术的发展及广泛应用于临床 ,对脑肿瘤瘤周水肿有了进一步的认识 ,现将这方面研究作一综述。1　 PTBE产生的有关因素1.1　 PTBE与脑肿瘤组织产生的一种细胞因子 ,即内皮生长通透因子 ( VEG/ PF)的阳性表达有密切关系 〔2 ,3〕,VEG/ PF可促进血管生成 ,增加毛细血管通透性 ,使血浆蛋白和水外溢 ,致使细胞外液增加 ,这时电镜下可见神经元缺失和退变 ,星形胶质细胞、毛细血管内皮细胞肿胀 ,…     

人胎副睾与输精管的组织学观察

取16－28周24例布依族人胎副睾及输精管，HE，PAS染色，示16周副睾上皮呈假复层柱状，胞质含较多粗大PAS阳性颗粒，游离面有纤毛，上皮基膜呈PAS阳性反应，随着胎龄增加，管腔增大，上皮变高，28周副睾管腔平整，上皮外有环行平滑肌，睾丸输出管呈明显不规则形，16周时输精管上皮呈单层柱状，肌层不明显，19周上皮已呈假复层柱状，未见纤毛，随着胎龄增加纤毛出现，环行肌层次增加后纵行肌出现，上皮基膜，纤毛呈PAS阳性反应，为研究人胎生长发育，提供形态学基础。     

北京鸭淋巴结毛细血管后微静脉的超微结构

对６周龄北京鸭淋巴结毛细胞血管后微静脉的电镜观察证明，其基本结构与哺乳动物有相似之处，但也有显著差异。毛细血管后微静脉多位于淋巴细胞聚集区（致密区），也见于淋巴组织索和结缔组织网状索内。管腔多不规则，管壁厚度不一。内皮游离面未见微绒毛。其横断面管径一般较细。管壁外调被网状细胞所环绕，管周未见巨噬细胞，内皮细胞基膜外有网状细胞及其突起，纤维和基质所环绕。可见淋巴细胞穿越管壁。     

A blood-brain barrier to peroxidase in capillaries surrounded by perivascular spaces

Some investigators have hypothesized that the absence of a blood-brain barrier in specialized regions of the mammalian central nervous system is related to the occurrence of a pericapillary connective tissue space that can accommodate more substance than the usual narrow extracellular space in the remainder of the cerebral parenchyma. The capillaries of the urodele brain are well suited to test this hypothesis. All of the cerebral capillaries examined electron-microscopically in Necturus maculosus are surrounded by a collagen-containing space, about 0.5 m? wide, which is delimited by an endothelial and a glial basement membrane. In Ambystoma tigrinum, some capillaries have perivascular spaces whereas others are surrounded by a single basement membrane shared by endothelium and glia and therefore resemble mammalian vessels exhibiting barrier phenomena. In both Necturus and Ambystoma, horseradish peroxidase administered intravenously one-half to two hours before fixation did not cross the brain capillary endothelium. The bulk of the protein remained in the vessel lumen, although some was incorporated by membrane-bound inclusions within the endothelium, and none ever reached the perivascular basement membrane, space or parenchyma. The amphibian cerebral endothelium is, like the mammalian endothelium, the locus for the barrier to the entry of peroxidase from blood to parenchyma. Thus, the mere occurrence of a pericapillary space is not necessarily coincident with the absence of a blood-brain barrier.     

局灶脑缺血再灌注区脑微血管基底膜损害及uPA、uPAmRNA表达的实验研究

目的:探讨脑缺血再灌注区脑微血管结构损害特征及发生机制。方法:应用光镜、透射电镜、免疫组织化学、原位分子杂交等技术,观察易卒中型肾血管型高血压大鼠局灶脑缺血2h再灌注6h至7d,再灌注区脑微血管结构改变、尿激酶型纤溶酶原激活物(uPA)表达。结果:局灶脑缺血再灌注区的脑水肿加重及并发出血以再灌注12h至3d最为严重,脑微血管基底膜溶解、缺损。同时使基底膜及细胞外间质降解的主要酶类uPA及uPAmRNA表达增加,以再灌注12h至3d达高峰。结论:脑缺血再灌注区脑微血管基底膜破坏是导致再灌注后脑水肿、出血的主要病理基础,内皮细胞、胶质细胞uPA表达的增加可能是引起微血管基底膜及细胞外间质损害的主要机制之一。     

Histamine in brain capillaries

A high amount of histamine was found in capillaries isolated by subcellular fractionation from the brain. In view of the important effects of histamine on vascular permeability in peripheral vessels, it was thought that histamine had a similar function in the cerebral vasculature. Intracarotic histamine infusion resulted in an enhanced pinocytosis of endothelial cells and the oedematous swelling of the astrocytic end-feet system. [³H]-Histamine, injected in the cerebral ventricles, accumulated in the capillary wall. Histamine and cimetidine activated hydroxyfatty acid and prostaglandin D₂ synthesis in isolated brain capillaries.The possible function of the capillary histamine in the regulation of permeability of microvessels is discussed.     

Glial cells and blood-brain barrier in the human cerebral cortex

The spatial relationship established between glial cells and microvasculature in the human cerebral cortex was analysed on peritumoral tissue of the parietal lobe removed during surgery. Observations performed by light microscope immunocytochemistry demonstrated that processes of astrocytes, strongly immunoreactive to both glial fibrillary acidic protein and S-100 protein, form sheaths to the capillaries, and that isolated cells positive to the oligodendrocyte marker 2',3'-cyclic nucleotide 3'-phosphodiesterase are detectable in perivascular areas. Morphometrical analysis by transmission electron microscopy showed that 80% of the vascular endothelium-pericyte layer is invested by small endfeet of astrocyte processes. This study demonstrates that either astrocyte bodies or oligodendrocytes as well as microgliocytes may substitute the astrocytic endfeet adhering to the capillary basement lamina.     

Absence of Ultrastructural Changes in the Basement Membrane of Muscle Capillaries in Streptozotocin-Induced Carbohydrate Intolerance in Rhesus Monkeys

The effects of streptozotocin-induced carbohydrate intolerance on the basement membrane of muscle capillaries were studied in 5 adult rhesus monkeys. Biopsies were obtained 6 to 15 months after administration of the drug. Although wide variations in the thickness of basement membranes were observed between capillaries in the same biopsy of each animal, no significant differences were found between the mean values of the experimental group when compared with those of 5 control animals. These results seem to support the “genetic theory” of diabetic microangiopathies. It may prove of considerable interest to repeat these observations in more chronic stages of carbohydrate intolerance.     

Hepatocytes modulate the hepatic microvascular phenotype.

The liver microvasculature is unique among epithelial organs because it is composed of sinusoids rather than capillaries. Since hepatocytes lack a basement membrane, they are not separated from plasma by any continuous filtration barrier. During the cirrhotic process, the sinusoids become transformed into typical continuous capillaries with specialized endothelial junctions, continuous basement membrane, and pericytes. To explore the factors that determine the phenotype of the hepatic microvasculature, we implanted fetal rat liver fragments onto the chorioallantoid membrane of 6-day-old, shell-less, quail embryos. After 5 days in culture they were studied by light and electron microscopy immunohistochemistry using markers specific for: quail cells, hepatocytes, and basement membrane components of murine or avian origin. The normal quail chorioallantoid membrane is vascularized by continuous capillaries. The periphery of the transplanted fetal rat liver fragments becomes vascularized by microvessels of quail origin. However, the quail microvessels in the proximity of rat hepatocytes assume a sinusoidal phenotype with fenestrations lacking diaphragms, endothelial cell gaps, and devoid of basement membrane. These results demonstrate that liver cells modulate the phenotype of the hepatic microvascular. Since hepatocytes and endothelium do not establish direct cell contacts, we postulate that this modulation is exerted either by secreted soluble cytokines or by the extracellular matrix.     

Evaluation of muscle capillary basement membrane in inflammatory myopathy

The capillary basement membranes from 16 skeletal muscle biopsies from patients with a clinical and histological diagnosis of inflammatory myopathy and from six controls were analysed ultrastructurally and morphometrically. Resin sections from 244 endomysial capillaries were examined by light microscope, and the results were correlated with findings seen in electron micrographs of these capillaries. The ultrastructural morphometric measurements and the statistical analysis showed that the capillary basement membrane was thick and multilaminated in 87% specimens affected by inflammatory myopathy. No thick or multilaminated basement membrane was observed in controls. In inflammatory myopathy the endomysial space next to the capillaries contained an increased amount of collagen fibrils and showed signs of a chronic reparative process. It is suggested that the thick multilaminated basement membrane in inflammatory myopathy represents an advanced stage of vascular regeneration.     

胃癌组织内淋巴管的形态计量学研究

目的；研究胃癌细胞淋巴道转移机理，方法用图像分析仪测定３２例胃癌组织及癌旁组织内有腔淋巴管和毛细淋巴管最大面积，周径和管径。结果：在胃癌组织内以条索状毛细淋巴管为多，而在癌旁组织内则以开放的淋巴管和毛细淋巴管为主，图像分析结果表明，转移组胃癌组织与癌旁组织内淋巴和和毛细淋巴管腔面积，周径和管径，两者间彼此差异均有显著性（Ｐ〈０．０５）；未转移胃癌组织与癌旁组织内淋巴管和毛细淋巴管腔面积，周径和管径     

Ultrastructures of the epithelial basement membrane and the subepithelial capillaries in rabbit palatine tonsils

The ultrastructure of both the epithelial basement membrane and the subepithelial capillaries in rabbit tonsils was investigated using light and transmission electron microscopy of sections, and scanning electron microscopy of alkali-water macerated tissues. The basement membrane of the crypt epithelium was seen to consist of the lamina lucida, lamina densa and lamina fibroreticularis. The lamina fibroreticularis is made up of both fine and thick collagen fibrils. The basement membrane possesses numerous pores (0.5-20 microns in diameter) through which free cells migrate. The basement membrane overlying the follicle protrudes hemispherically towards the crypt lumen, while that over the interfollicular area forms many papillary projections. The capillaries are surrounded by collagen fibrillar sheaths invariably located below the collagen fibrillar sheet of the epithelial basement membrane. The capillaries immediately below the crypt epithelium, including switch-back loops of capillaries in the papillae, are fenestrated sinusoids (20-40 microns in diameter). Plasma cells, lymphocytes and macrophages are numerously gathered around the capillaries. Possible functional relations between these free cells and the fenestrated sinusoids are discussed.     

Alterations in rat's brain capillaries in a model of focal cerebral necrosis.

Focal brain compression causes cerebral tissue damage. In this study we followed alterations in capillary ultrastructure in the rat cortex and neurohypophysis caused by 40 mm Hg compression for 15 minutes. One day after experiment we observed clogging of capillaries, accumulation of collagen fibrills under the basement membrane and necrosis or apoptosis of endothelial cells. Four days after it the basement membrane was multiplicated, blurred and thickened. In the neurohypophysis the formation of vessels lined with the atypical continuous endothelium was seen. There was also evidence for the migration of pericytes through the blurred basement membrane and the differentiation of pericytes into endothelial cells. Thus, vascular injury in the compressed brain is followed by a highly ordered sequence of processes in the basement membrane and perivascular cells leading to capillary repair.