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近年有关ＶＥＧＦ的研究进展迅速 ,发现其在肿瘤的发生发展中起着极其重要的作用。肿瘤的新生血管形成 ,不仅为肿瘤的增长提供营养和气体交换 ,而且也是肿瘤细胞浸润、转移的直接途径。肿瘤血管的启动是由肿瘤细胞分泌的促内皮细胞增殖和迁移的多种血管生长因子所诱发 ,诸如ＶＥＧＦ、碱性成纤维细胞生长因子 (ｂａｓｉｃｆｉｂｒｏｂｌａｓｔｇｒｏｗｔｈｆａｃｔｏｒ ,ｂＦＧＦ)、转化生长因子α(ｔｒａｎｓｆｏｒｍｉｎｇｇｒｏｗｔｈｆａｃｔｏｒα ,ＴＧＦα)、血小板衍生因子 (ｐｌａｔｅｌｅｔ-ｄｅｒｉｖｅｄｇｒｏｗｔｈｆａｃｔｏ…     

胆系恶性肿瘤VEGFmRNA、bFGFmRNA、PDGFmRNA表达及意义

肿瘤的生长和转移均需血管生成 ,主要的促血管生成因子有血管内皮生长因子 (ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｏｔｒ ,ＶＥＧＦ)、碱性成纤维细胞生长因子 (ｂａ ｓｉｃｆｉｂｒｏｂｌａｓｔｇｒｏｗｔｈｆａｃｔｏｒ ,ｂＦＧＦ)和血小板衍生生长因子 (ｐｌａｔｅｌｅｔｄｅｒｉｖｅｄｇｒｏｗｔｈｆａｃｔｏｒ ,ＰＤＧＦ)。近年研究发现ＶＥＧＦ、ｂＦＧＦ、ＰＤＧＦ及其ｍＲＮＡ表达与一些恶性肿瘤生物学行为、转移发生及其预后有密切关系〔13〕。作者应用原位杂交染色技术研究胆囊癌和肝外胆管癌组织中ＶＥＧＦ…     

VEGF、VEGFR与皮肤肿瘤的研究进展

血管内皮生长因子 (ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｔｏｒ,ＶＥＧＦ) [1] ,又称为血管渗透性因子 (ｖａｓｃｕｌａｒｐｅｒｍｅａｂｉｌｉｔｙｆａｃ ｔｏｒ) [2 ] ,和血管增殖因子 (ｖａｓｃｕｌｏｔｒｏｐｉｎ) [3] 。至 2 0世纪 80年代末 ,ＶＥＧＦ被确认为有提高血管通透性和内皮细胞的最有效有丝分裂原[1] ,此后又有多种生长因子被确认与血管生长有关。然而正如 2 0 0 0年ＮＡＴＵＲＥ杂志著文认为[4 ] :“迄今为止 ,只有ＶＥＧＦ被确认具有高度特异 ,及有效的促新生血管形成作用”。而目前关于ＶＥＧＦ的…     

血管内皮细胞生长因子用于基因治疗的进展

血管内皮细胞生长因子(ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｔｏｒ,ＶＥＧＦ)又名血管通透性因子(ｖａｓｃｕｌａｒｐｅｒｍｅａｂｉｌｉｔｙｆａｃｔｏｒ,ＶＰＦ),目前已阐明其在生理及病理血管再生中起关键性作用[1]。由于血管再生不仅是组织器官再生的基础,而且也是参与许多疾病诸如肿瘤、类风湿性关节炎、视网膜等疾病的发病机制之一,因而促进或抑制血管内皮细胞生长因子的表达进而以用来治疗各种疾病已越来越受到重视。一、血管内皮细胞生长因子及其受体特点1.血管内皮细胞生长因子特点:血管内皮细胞生长因子(Ｖ…     

骨生长因子与骨重建研究进展

骨重建 (ｂｏｎｅｒｅｍｏｄｅｌｉｎｇ)是指骨的形状、密度分布随时间的变化而改变 ,受到骨生长因子、年龄、局部血供、营养及力学环境等诸多因素的影响〔1〕。多种细胞因子〔1～ 7〕,如转化生长因子 β(ＴｒａｎｓｆｏｒｍｉｎｇＧｒｏｗｔｈＦａｃｔｏｒ ｂｅｔａ ,ＴＧＦ β)、骨形态发生蛋白 (ＢｏｎｅＭｏｒｐｈｏｇｅｎｅｔｉｃＰｒｏｔｅｉｎｓ,ＢＭＰｓ)、成纤维细胞生长因子 (ＦｉｂｒｏｂｌａｓｔＧｒｏｗｔｈＦａｃｔｏｒ,ＦＧＦ)、胰岛素样生长因子 Ⅰ / Ⅱ (Ｉｎｓｕｌｉｎ ｌｉｋｅＧｒｏｗｔｈＦａｃｔｏｒ Ⅰ / Ⅱ ,ＩＧＦ…     

碱性成纤维细胞生长因子与脊髓损伤

脊髓损伤 (ｓｐｉｎａｌｃｏｒｄｉｎｊｕｒｙ ,ＳＣＩ)是临床上常见的疾病 ,且致瘫率高 ,严重地危及人类健康。脊髓损伤与很多生长因子有关。研究表明 ,碱性成纤维细胞生长因子 (ｂａｓｉｃｆｉｂｒｏｂｌａｓｔ ｇｒｏｗｔｈｆａｃｔｏｒ ,ｂＦＧＦ)的生物学作用极其广泛 ,它在胚胎发育、血管生成、促进创伤愈合与组织修复、促进组织再生及神经系统生长发育等许多方面发挥着重要的生物学调节作用[1] 。现有关ｂＦＧＦ的研究不断深入 ,并取得令人鼓舞的成果。本文就ｂＦＧＦ在脊髓中的表达及ｂＦＧＦ对脊髓损伤的作用等方面的研究近况作一…     

血管内皮生长因子与骨的形成及修复

血管内皮生长因子ｖａｓｃｕｌａｒｅｎ-ｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｔｏｒ,ＶＥＧＦ作为一种人属二聚蛋白信号肽,其多功能细胞素作用贯穿于人类生殖、发育、组织再生和修复以及肿瘤发生等生理、病理过程。我们通过对ＶＥＧＦ及其受体与成骨细胞、血管内皮细胞、骨     

血管内皮生长因子与治疗性血管生成

近年来 ,由于分子生物学等基础学科的迅猛发展 ,缺血性及其相关疾病的治疗取得了长足的进步。其中 ,以增加新生血管、改善缺血为主要目的的治疗性血管形成 (ｔｈｅｒａｐｅｕｔｉ ｃａｌａｎｇｉｏｇｅｎｅｓｉｓ)广泛地应用在各类缺血及其相关性疾病的实验和临床研究中。血管形成 (ａｎｇｉｏｇｅｎｅｓｉｓ)在机体的生长发育、新陈代谢、脏器修复、创伤愈合和生殖过程中均起着重要作用[1] ,有很多因素与之有关 ,其中 ,血管内皮细胞生长因子(ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｔｏｒ,ＶＥＧＦ)的作用最为突出 ,尤…     

血管内皮生长因子基因治疗与组织缺血损伤修复

组织缺血损伤在整形外科中目前仍是一个重要的问题。缺血的原因通常归结于组织的动脉供血不足 ,静脉回流不畅 ,或两者共同作用的结果。现在已发现能诱导新血管形成和改善组织缺血状态的许多血管生长因子中 ,血管内皮生长因子 (ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｔｏｒＶＥＧＦ)是作用最强、特异性最高的因子 ,它作用的受体仅发现在内皮细胞上。研究ＶＥＧＦ基因治疗在组织缺血损伤修复中的作用 ,对促进整形外科的发展有着重要意义。1　ＶＥＧＦ的生物学特性　1.1　ＶＥＧＦ的基因结构和同种异形体　利用聚合酶链反…     

血管内皮生长因子其家族与基因治疗

血管内皮生长因子 (Ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｔｏｒ,ＶＥＧＦ)在 80年代早期被Ｄａｏｒａｋ[1,2 ] 及其同事发现 ,能够引起血管内液渗漏 ,所以又将其命名为血管通透因子 (ＶａｓｃｕｌａｒＰｅｒｍｅａｂｉｌｉｔｙｆａｃｔｏｒ ,ＶＰＦ) ,随后的 80年代后期 ,几个研究机构发现ＶＰＦ具有刺激血管内皮细胞增殖的作用 ,是一种潜在血管生成因子 ,又将其命名为ＶＥＧＦ。是迄今所发现最强的一种血管生成因子。ＶＥＧＦ的 5种形式一、ＶＥＧＦ是一种糖蛋白 ,分子量为 34～ 46ＫＤ ,为同二聚体分子。由于其ｍＲ…     

Hazards and complications of endoscopic transurethral ureterolithotripsy and lithoextraction and means of prevention

Complications related to ureterolithotomy and ultrasonic ureterolithotripsy performed under the control of visual endoscope were analyzed in 86 ureterolithiasis patients, methods of their prevention discussed. All the aforementioned complications were distributed into three groups: inapplicability of surgery due to anatomic and functional defects of lower and upper urinary tracts, intraoperative, and postoperative complications. The commonest ones were ureteral abruption and perforation, acute pyelonephritis, temporary vesicoureteral reflux. Their control measures were considered as relative methods of treatment: immediate surgical intervention in case of ureteral abruption, renal catheterization in patients with insignificant ureteral perforation or acute pyelonephritis. Adequate ureteroscopy, careful consideration of pro- and contraindications, catheterization of renal pelvis and urinary bladder performed within 2-3 days after the surgery and adequate antibacterial therapy are the most decisive steps in the control of aforementioned complications.     

牙体牙弓颌骨阻力中心及其临床意义

牙体、牙弓及颌骨的阻力中心在正畸矫治力系统中具有重要的意义,也是正畸学领域争论较多的一个问题。Dermaut等研究表明,当力作用于物体阻力中心时,物体将发生平动,否则将发生平动和转动的复合运动。目前,国内外多数学者认为牙体、牙弓及颌骨存在阻力中心,但其位置存在争议。本文就牙体、牙弓及颌骨的阻力中心及其临床意义作一综述。     

Characterisation and differentiation of chondroblastomas and chondromyxoidfibromas - presence and expression of collagen types I and II

AIM: Chondroblastomas and chondromyxoidfiibromas are rare benign skeletal neoplasms with reported overlapping histology. Aim of this study was to analyse the biochemical composition of the matrix of these tumour entities in order to further characterise the cellular phenotypes of these neoplasms using typical cell biological marker genes. METHODS: The matrix compositions of chondroblastomas and chondromyxoidfibromas were analyzed by HE-histology, histochemistry, and immunolocalization techniques. Cellular gene expression patterns were detected by mRNA in situ hybridization. RESULTS: Chondroblastomas are rich in collagen type I and show foci of an osteoid-like matrix, whereas collagen type II as a typical marker of chondrocytic differentiation was not detected in any of the specimens. Chondromyxoidfiibromas had foci of chondroid appearance with chondroblastic cellular differentiation characterised by collagen type II expression. CONCLUSION: These results characterise chondroblastomas and chondromyxoidfiibromas as skeletal neoplasms that have a different biology and which can be distinguished by matrix protein expression products: collagen type II, the typical marker of chondroblast differentiation, could only be detected in chondromyxoidfibromas, but not in chondroblastomas. Thus, both neoplasms are clearly different on the cell biological level.     

Histochemical and contractile properties of striated muscles of urethra and levator ani of dogs and sheep

AIMS: To understand their possible importance in long- and short-term control of continence, some properties of the striated muscles of the urethra and pelvic floor (levator ani) of dogs and sheep were investigated, especially fiber types and contractile characteristics. MATERIALS AND METHODS: Striated muscles of urethra and levator ani of 29 male and 6 female dogs and 11 male and 6 female sheep were removed and cut into strips. Some strips were frozen and stained for ATPase at pH 9.4 and 4.3 for fiber typing; others were set up in an organ bath to study contractile responses to nerve stimulation. RESULTS: All muscles contained both type I (slow) and type II fibers, ranging from 97% type II in female greyhound urethra to 60% in female sheep levator ani. For each muscle, there were fewer type II muscles in sheep than in dog. The diameters of the urethral fibers were about 60% of the levator ani in dogs and 34% in sheep. Contraction of the urethral muscle was faster than for levator ani and declined to about 80% of the peak, 500 msec after the beginning of stimulation at 20 Hz. The levator ani contraction rose to a steady level as long as stimulation continued. CONCLUSIONS: Both the levator ani and urethral striated muscles contain slow and fast fiber types. The levator ani muscles are capable of sustained contraction with rapid onset which will produce long-term closure of the urethra. The circular urethral muscle contraction was faster but less well maintained.     

Incorporation and release of85Sr and14C-proline-hydroxyproline in mineral and collagen of bone and incisor teeth of growing rats

The extent to which exchange and reutilization processes of mineral tracers affect skeletal mineral accretion and resorption measurements was evaluated by comparing the rates of appearance and disappearance of⁸⁵Sr and¹⁴C-proline-hydroxyproline in bones and teeth in growing rats for 12 days following simultaneous parenteral injection of these tracers. Expressions for the relative rates of collagen synthesis and breakdown, which unlike mineral metabolism are considered not to be complicated by exchange phenomena, were based on¹⁴C-proline conversion to¹⁴C-hydroxyproline; the specific activity of the latter was determined. Both the mineral and the collagen specific activities reflected the rates and patterns of growth of the samples assayed; rapid growth and a short interval of time between formation and resorption of tissue in themetaphyseal bone which contains the cartilagineous growth plate, slow growth and an interval of time between formation and resorption of tissue indiaphyseal bone and incisor teeth which is longer than the 12 days of the experiment. However, in metaphyseal bone the specific activity collagen/mineral ratio dropped by one half during the 4–12 day interval in contrast to diaphyseal bone and incisor teeth in which no change in this ratio was observed during this period of time. The data indicate that collagen in the metaphyseal growth zone is removed by resorption before it has become fully mineralized, and that exchange is a relatively unimportant factor in the long term kinetics of bone mineral.

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Zusammenfassung Das Ausmaß, bis zu welchem Austausch- und Wiederverwendungsprozesse der mineralen Tracer die Messungen des mineralen Skelett-Auf- und Abbaues beeinflussen können, wurde ausgewertet; zu diesem Zweck wurde die Geschwindigkeit des Auftretens und Verschwindens von⁸⁵Sr und von¹⁴C-Prolin-Hydroxyprolin in Knochen und Zähnen von wachsenden Ratten während der 12 auf die simultane parenterale Injektion dieser Tracer folgenden Tage verglichen.Der Ausdruck für die relative Geschwindigkeit des Kollagen-Auf- und Abbaues, bei welchem im Gegensatz zum Mineralmetabolismus kein Mitwirken des Austauschphänomens vermutet wird, basiert auf der Umwandlung von¹⁴C-Prolin zu¹⁴C-Hydroxyprolin; die spezifische Aktivität des letzteren wurde bestimmt.Aus der spezifischen Aktivität des Minerals sowie jener des Kollagens konnten die Geschwindigkeit und die Art des Wachstums der untersuchten Proben ersehen werden, d.h.schnelles Wachstum und ein kurzes Zeitintervall zwischen Bildung und Resorption des Gewebes imKnochen der Metaphyse, die auch die knorpelige Wachstumsplatte enthält, und andererseitslangsames Wachstum und längeres Zeitintervall (länger als die 12 Tage des Experimentes) zwischen Bildung und Resorption des Gewebes imKnochen der Diaphyse und in den Schneidezähnen. Immerhin fiel die spezifische Aktivität des Kollagen/Mineral-Anteils im Knochen der Metaphyse während dem 4–12tägigen Zeitintervall auf die Hälfte, im Gegensatz zum Knochen der Diaphyse und der Schneidezähne, bei welchen während dieser Zeitspanne kein Unterschied in diesem Verhältnis beobachtet wurde.Diese Ergebnisse zeigen, daß Kollagen in der Wachstumszone der Metaphyse durch Resorption verschwindet, bevor es ganz mineralisiert ist, und daß der Austausch ein relativ unwichtiger Faktor in der Kinetik auf lange Sicht des Knochenminerals ist.