人脐静脉组织构筑及其临床应用价值

本研究旨在为脐带静脉作为小口径移植材料的临床应用提供理论依据。采用胎龄在 2 4～ 4 2周脐带静脉 5 0例 ,常规石蜡包埋、切片。用HE法、Weigert法、苯胺蓝法及桔黄G法分别染组织结构、弹性纤维 胶原纤维和平滑肌。光镜观察后 ,用计算机图像分析系统测量其中膜显微结构成分的相对含量。随胎龄增加 ,脐带静脉中膜弹性纤维含量逐渐增多 ,胶原纤维含量及C/E值逐渐减少 (P <0 0 1)。近段胶原纤维含量比远段少 (P <0 0 1) ,由近段到远段C/E值逐渐增大。脐带静脉具有与普通中等动脉相似的结构 ,作为小口径动脉移植的替代材料是可行的 ,建议选用胎龄在 37～ 4 0周之间的脐带静脉作为临床应用的移植材料。同时应注意选择不同段脐带静脉 ,使移植材料与宿主血管间的组织构筑尽可能相近 ,以提高移植血管的远期通畅率。     

不同段脐带静脉的生物力学特性及其临床应用价值

目的 :为脐带静脉作为小口径移植材料的临床应用提供理论依据。方法 :采用胎龄在 3 7～ 40周自然分娩正常胎儿脐带静脉 2 0例 ,在生物软组织力学试验机上测定不同段脐带静脉的压力 -直径关系 ,计算出弹性模量。横断取材 ,冰冻切片 ,HE法染色 ,用计算机图像分析系统测量其几何形态学指标。结果 :近、中、远段脐带静脉的Einc、Ep和Ev均随压力的上升而增大 ,近段 3种弹性模量均低于远段 (P <0 .0 1) ,由近段到远段呈增大趋势。中膜厚度及外径值从近段到远段逐渐减小。结论 :脐带静脉作为小口径动脉移植的替代材料是可行的 ,在血管移植时 ,应注意选择不同段脐带静脉 ,使作为移植材料的脐带静脉与宿主血管材料间的生物力学特性尽量相近 ,以提高移植血管的远期通畅率     

胎儿静脉壁组织结构增龄性变化的定量分析

目的：探讨胎儿脐带静脉随胎龄变化的形态学改变，为临床挑选适当的血管代用品提供科学的理论依据。方法：33例新鲜脐带，常规石蜡包埋、切片、HE染组织结构，Weigert,Aniline Blue及桔黄G分染弹性纤维，胶原纤维和平滑肌，光镜观察及计算机图像分析。结果：随胎龄随长，脐静脉管径、中膜厚度、中膜弹性纤维含量逐渐增多；平滑肌含量及细胞核的数密度和面密度在37－40周最大（P＜0．05），胶原纤维则最小，因而此时段顺应性最好。结论：脐静脉管壁中各成分的含量随胎龄变化呈不等比增长，37－40周时血管顺应性最好。建议选用此时段胎龄的脐静脉作为移植材料。     

胎儿脐静脉壁组织结构增龄性变化的定量分析

目的 :探讨胎儿脐带静脉随胎龄变化的形态学改变 ,为临床挑选适当的血管代用品提供科学的理论依据。方法 :3 3例新鲜脐带 ,常规石蜡包埋、切片、HE染组织结构 ,Weigert,AnilineBlue及桔黄G分染弹性纤维 ,胶原纤维和平滑肌 ,光镜观察及计算机图像分析。结果 :随胎龄随长 ,脐静脉管径、中膜厚度、中膜弹性纤维含量逐渐增多 ;平滑肌含量及细胞核的数密度和面密度在 3 7～ 40周最大 (P <0 .0 5 ) ,胶原纤维则最小 ,因而此时段顺应性最好。结论 :脐静脉管壁中各成分的含量随胎龄变化呈不等比增长 ,3 7～ 40周时血管顺应性最好。建议选用此时段胎龄的脐静脉作为移植材料。     

胎儿脐带静脉的蠕变特性

为脐带静脉作为小口径移植材料的临床应用提供蠕变特性指标。对产妇年龄在22～28岁,胎龄37～40周自然分娩正常胎儿脐带静脉近胎盘段和远胎盘段各10个试样在日本岛津电子万能试验机上进行蠕变实验,模拟人体温在36.5±0.5℃的温度场下以0.01 Mpa/s的应力增加速度对试样施加应力,设定时间为7 200 s。采集100个数据,采用归一化分析的方法计算两组试样的归一化蠕变方程。两组试样蠕变曲线是以指数关系变化的,胎儿脐带静脉近胎盘段和远胎盘段7 200 s蠕变量差异显著(P<0.05)。胎儿脐带静脉近胎盘段和远胎盘段具有不同的蠕变特性。     

肝门静脉高压症猪肝门静脉的结构重建

目的:建立猪肝门静脉高压症模型,探讨肝门静脉高压症时肝门静脉的结构重建.方法:猪以四氯化碳、苯巴比妥、乙醇配合高脂、低蛋白、低胆碱饮食进行混合饲养.通过脾静脉插管测压,取门静脉常规石蜡包埋、切片,用H-E 染色法、Weigert法、Aniline blue法、Organge G法分别染组织结构、弹性纤维、胶原纤维和平滑肌,用计算机图像分析系统定量分析肝门静脉的几何形态及显微成分.结果:实验组肝门静脉压为(4.17±1.03)kPa,而正常组为(1.51±0.79)kPa,实验组门静脉的内膜与中膜增厚,管壁增厚,管径增粗,平滑肌、胶原纤维的百分含量增加,平滑肌细胞核的数密度和面密度也在增加,C/E值增加.结论:肝门静脉高压症时,与血液动力学改变相适应,肝门静脉的几何形态与显微结构成分均发生了改变.     

人与猪肝门静脉显微结构成分的比较

目的：比较人与猪肝门静脉壁结构成分的异同，为猪一人异种肝移植提供理论依据。方法：取正常成人与不同月龄猪肝门静脉，常规石蜡包埋、切片，分染弹性纤维、胶原纤维和平滑肌，光镜观察，计算机图像分析系统测量各结构成分的相对含量。结果：随月龄的增长猪肝门静脉胶原纤维的含量逐渐升高，弹性纤维的含量相对稳定，平滑肌的含量在3月龄时最高，C厄值逐渐升高。与人相比，猪肝门静脉壁中胶原纤维和弹性纤维的含量较低，而平滑肌的含量则较高，5、6月龄时的C/E值与人相近。结论：人与猪肝门静脉壁各结构成分的含量存在差异，但从C僵值看，5、6月龄猪肝门静脉的力学特性与人相匹配，较适合用于移植。     

不同胎龄脐带静脉顺应性的变化及其临床意义

目的：为脐带静脉的临床应用从生物力学性质上提供理论依据。方法：采用胎龄以24－42周流产及自然分娩正常胎儿脐带静脉50例，测定其压力－容积关系。结果：脐带静脉的p-V曲线可用抛物线拟合。脐带静脉顺应性随胎龄增加而增大，但39周以后又降低。结论：人脐带静脉是动脉移植物的良好替代材料，在移植时除了考虑脐带静脉与宿主动脉相匹配外，还应注意其顺应性与胎龄的关系，建议选用胎龄在37－40周之间的脐带静脉作为临床应用的移植材料。     

左髂总静脉的形态学研究及其临床意义

目的：研究左髂总静脉（LCIV）受压部位及相邻节段的结构特征,以探讨LCIV受压段的血管重塑及力学特性.方法：解剖80例成年尸体（男42例,女38例）,观测LCIV受压段及相邻节段外径、右髂总动脉（RCIA）与LCIV的相交角度以及右髂总静脉（RCIV）相应部位的外径;随机选择18例标本采用 Masson染色,观测受压段及其近侧、远侧段以及对侧相应部位的平滑肌（SM）、弹力纤维（EF）、胶原纤维（CF）等组织成分的变化.结果：受压段静脉管壁塌陷、菲薄.与对侧相应部位及受压处近侧和远侧段相比,受压处管径扩大（P＜0.01）;与RCIV比较,LCIV各节段SM相对含量降低,而CF和EF相对含量增加（P＜0.05）;与相邻节段相比,除近侧段的EF以外,其他各项指标差异都具有显著的统计学意义（P＜0.05）.结论：（1）LCIV的受压,引起血流动力学改变,诱导血管重塑,管壁弹性成分改建以及粘连结构的出现.（2）上述形态改变进一步引起血流动力学紊乱,从而加剧组织学的改变.（3）这一系列变化可能是导致髂-股静脉血栓形成和髂静脉压迫综合征发生的重要原因.     

胎儿脐带静脉的生物力学特性研究

探讨胎儿脐带静脉随胎龄变化的生物力学特性的改变,为临床挑选适当的血管代用品提供理论依据。方法：33例新鲜脐带静脉,用生物软组织力学试验机测定血管的压力、容积、外径等力学参数,计算出弹性模量、顺应性。结果：37－40周时脐静脉的P－V曲线比较高,弹性模量与血压的关系曲线较低,此时段顺应性最好。结论：建议选用胎龄在37－40 周之间的脐静脉作为移植材料。     

Biomechanical properties of different segments of human umbilical cord vein and its value for clinical application

No satisfactory effects have been obtained with the use of synthetic blood vessels (diameter <6 mm) as substitutes for human small arteries or veins for the purpose of clinical vascular reconstruction. Therefore, blood vessels of human origin, for example, umbilical cord blood vessels, with their wide availability, still should be considered. However, little information on biomechanical properties of human umbilical cord blood vessels is available. The objective was to provide a theoretical basis for the clinical application of umbilical cord veins as optional material for small-caliber grafts. This was a nonrandomized, noncontrolled in vitro study. The experiment was conducted in the Laboratory of Medical Biomechanics, Yunyang Medical College. Umbilical cord veins of 20 normal fetuses of spontaneous labor were collected by the Department of Obstetrics and Gynecology, Taihe Hospital in Shiyan City, Hubei Province. The fetuses aged 37-40 weeks, and the parturients were 20-30 years old. Umbilical cord veins of the 20 fetuses were used and the placental ends were treated as proximal ends while the fetal ends as distal ends. The fetal ends were divided into three segments: proximal, middle, and distal segments. The relationship between pressure of umbilical cord veins segments and the diameters was measured on the biomechanical experiment stand for soft tissues, and then the elastic modulus was calculated. The materials were transversely extracted, refrigerated, and sliced up before HE staining. The geometrical morphology indexes were measured by a computer image analysis system (Leica-Q500IW). The main outcome measures were: incremental elastic modulus (E(inc)), pressure-strain elastic modulus (E(p)), volume elastic modulus (E(v)), diameter, and wall thickness of the veins. E(inc), E(p), and E(v) of umbilical cord veins of proximal, middle, and distal segments increased with the pressure elevated. The three kinds of elastic modulus of proximal segments (E(inc): 26.98 +/- 3.21, E(p): 16.58 +/- 2.12, E(v): 8.31 +/- 2.35) were all lower than those of distal segments (E(inc): 33.20 +/- 4.21, E(p): 119.45 +/- 2.87, E(v): 9.71 +/- 1.32) (F = 95.74-126.52, p < 0.05), and a tendency to increase was shown from proximal segments to distal segments. Media thickness [(0.30 +/- 0.05)] mm, (0.24 +/- 0.03) mm] and the diameters [(3.07 +/- 0.12) mm, (2.30 +/- 0.13) mm] decreased gradually from proximal to distal segments (F = 12.76, p < 0.01). It is feasible to use umbilical cord veins as substitutes for the transplantation of small-caliber arteries in terms of basic biomechanical properties. On vascular grafting, different segments of umbilical cord veins should be chosen cautiously so that the biomechanical characteristics of umbilical cord vein grafts could be in accordance with those of host to increase the long-term patency rate of transplanted blood vessels.     

Microscopic anatomy of brachial plexus branches in Wistar rats

In the present study, we analyze the morphology and morphometry of the lateral proper digital nerve of the third finger, and of the proximal and distal segments of the ulnar, median, and radial nerves, in Wistar rats 4 or 7 weeks old. The fascicular area and diameter were generally significantly greater in the proximal compared to distal segments and tended to be larger in 7‐week‐old compared to 4‐week‐old rats (e.g., median nerve area of 0.13 mm² for the proximal and 0.07 mm² for distal segments in 4‐week‐old rats, and 0.17 and 0.10 mm², respectively, for the proximal and distal segments of 7‐week‐old rats). The number of fascicles was significantly greater while the number of myelinated fibers was significantly less in the distal segments (e.g., 1,359 and 509 myelinated fibers, respectively, in the proximal and distal segments of the radial nerve 4‐week‐old rats). There was no significant difference in these parameters between the two age groups. The diameter of the myelinated fibers and their respective axons increased from 4 to 7 weeks of age (e.g., myelinated fiber diameter of 4.10 μm in 4‐week‐old animals and 4.7 μm in the ulnar nerve proximal segment of 7‐week‐old rats). The g‐ratio regression line (axon diameter vs. fiber diameter quotient) was outlined for all the nerves studied here. Differences in myelinated fiber density were detected between the segments of the radial nerve, accompanying the number of myelinated fibers. Detailed knowledge of the microscopic anatomy of rat forelimb nerves provides control data for comparison with studies of experimentally induced neuropathies, which can shed more light on human neuropathies. Anat Rec, 290:477–485, 2007. © 2007 Wiley‐Liss, Inc.     

人脐静脉来源的间质干细胞体外分离扩增及多向分化的研究

目的： 探讨人脐静脉来源的间质干细胞(MSCs) 的体外分离、纯化、扩增和多向分化条件。 方法： 无菌条件下取正常人脐静脉,1%胶原酶Ⅱ消化脐静脉细胞，以IMDM作为培养基进行培养和纯化细胞，瑞氏染色和电镜观察形态；FACS检测其免疫表型和细胞周期；体外诱导成骨细胞、脂肪细胞分化，von Kossa染色、油红O染色和RT-PCR检测骨钙蛋白、脂蛋白脂酶mRNA的表达以检测细胞向成骨、成脂肪细胞分化情况。 结果： 脐静脉来源的细胞呈纤维样贴壁生长，瑞氏染色和电镜观察具有MSCs特征；FACS检测结果显示, 表达MSCs相关的抗原CD29、CD44、CD105，而CD31、CD13、CD34、CD45、HLA-DR为阴性；体外诱导成骨细胞、脂肪细胞分化成功。 结论： 人脐静脉来源的MSCs的细胞形态、生长特性、免疫表型、多向分化能力与骨髓来源的MSCs相似，可作为满足实验和临床需要的MSCs来源。     

Segmental variability of membrane conductances in rat and human colonic epithelia

The membrane conductances in proximal and distal segments of rat and human colon were studied with microelectrodes, nystatin, ion channel blockers and Cl replacement. The results reveal that (1) in rat colon, total conductance (G ₁) is greater in the proximal segment than in the distal segment, reflecting greater values of apical (G _a) and paracellular shunt (G _s) conductances in the proximal segment; in contrast, in human colon,G _t and its individual membrane components are similar in the proximal and distal segments, and lower than the corresponding values in rat colon; (2) amiloride-sensitive apical Na conductances are absent in rat proximal colon, rat distal colon, and human proximal colon, but in human distal colon amiloride produces changes consistent with blockade of an apical Na conductance and inhibition of electrogenic Na transport; (3) a TEA-sensitive apical K conductance may be present in rat proximal colon (a K secretory epithelium), but not in rat distal colon (a K absorptive epithelium) or in either segment of human colon; and (4) in rat colon, replacement of mucosal and serosal Cl produces changes consistent with a substantial paracellular shunt permeability to Cl which is more marked in the proximal segment, whereas in human colon Cl replacement results in changes which suggest a relatively small paracellular shunt permeability to Cl which is similar in both segments. These data indicate marked segmental differences in Na, K and Cl transport in rat and human colon, and emphasise the hazards of applying models of colonic electrolyte transport in one species to another.     

The effect of pressure on the morphology of superior mesenteric vein in rabbits]

The effect of pressure on the morphology of the superior mesenteric vein of rabbits (SMV) was researched with the method of constant pressure fixation. The results indicate the morphology of SMV is similar to human umbilical cord vein. It looks like the structure of femoral artery of vein in many ways. Under constant pressure fixation (4 kPa), the internal elastic membrane of SMV is straightened, and the wall of SMV becomes thin, with its media thinning from 51.680 microns to 32.3260 microns. The long diameter of nucleus of the smooth muscles decreases from 1.9146 microns to 3.4980 microns, the short diameter of nucleus of the smooth muscles becomes from 0.7884 micron to 0.5228 micron. The direction of the tension on the smooth muscles is mainly longitudinal.