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101.
人发角蛋白桥接周围神经缺损的形态学观察 总被引:2,自引:1,他引:1
目的 :了解人发角蛋白在神经再生中的作用 ,为临床桥接周围神经缺损寻求新的替代材料。方法 :将 18只新西兰兔的双侧坐骨神经切断 ,造成 10mm缺损 ,一侧用人发角蛋白桥接 (实验组 ) ,另一侧用空硅胶管桥接 (对照组 ) ,术后 1、 2、 3个月通过肉眼观察 ,光镜、电镜和有髓神经密度测定 ,观察、分析神经再生情况。结果 :实验组再生神经均通过 10mm缺损 ,对照组有 2例无神经生长 ;实验组再生神经排列较紧密、有序 ,髓鞘形成早于对照组 ;神经纤维密度明显高于对照组 (P <0 0 1)。结论 :人发角蛋白可促进周围神经再生 ,是桥接周围神经缺损的理想材料。 相似文献
102.
目的:观察体外联合培养的成纤维细胞对平滑肌细胞形态和增殖的影响,为研究成纤维细胞和平滑肌细胞生物学特性和相互关系以及体外构建含此两种细胞的组织工程皮肤提供理论和实践基础。方法:在体外分别分离培养成纤维细胞和平滑肌细胞并常规传代培养。模拟组织工程皮肤的结构及成纤维细胞和平滑肌细胞间的相互影响途径,按照不同比例(平滑肌细胞:成纤维细胞=1:1,1:2,1:3)建立以胶原凝胶为基质的成纤维细胞与平滑肌细胞联合培养模型。应用荧光标记、组织学观察和MTT法对平滑肌细胞的形态和代谢进行研究。结果:联合培养模型法可以有效地建立起成纤维细胞和平滑肌细胞的相互影响模式。1:1组的成纤维细胞对联合培养的平滑肌细胞增殖有促进作用,1:3组的促增殖作用则不明显。结论:1:1联合培养的成纤维细胞对平滑肌细胞增殖有促进作用,对它们体外培养和扩增以及相互关系的研究对阐明这两种细胞组合作为真皮替代物种子细胞具有重要的意义。 相似文献
103.
Abstract
Fifty moderate to severe hallux valgus deformities were corrected with a distal soft tissue realignment and proximal crescentic
metatarsal osteotomy. With an average follow-up of 5.6 years, 40 feet (80%) were pain free and 42 (84%) caused no functional
limitation. The average hallux valgus angle improved from 38.2° preoperatively to 12.4° at follow-up. The average intermetatarsal
angle improved from 15.4° to 6.8°. The arch of motion of the first metatarsophalangeal joint was 75° preoperatively and 62°
at follow-up. According to the AOFAS scoring system, 29 results (58%) were excellent, 14 (28%) good, 2 (4%) fair and 5 (10%)
poor. The 5 poor results were attributed to recurrence of hallux valgus (2 cases), stiffness (1), hallux varus (1) and malunion
of the osteotomy in dorsiflexion (1). The incidences of hallux varus and malunion in dorsiflexion were 8% and 14%, respectively.
This technique is valuable in correction of moderate to severe hallux valgus deformities. 相似文献
104.
Jean-Fran ois Marini Fran oise Pons Jocelyne Leger Nathalie Loffreda Monique Anoal Martine Chevallay Michel Fardeau Jean J. Leger 《Neuromuscular disorders : NMD》1991,1(6):397-409
The expression of MHC isoforms in the skeletal muscles of nine patients with Duchenne muscular dystrophy (DMD) (from 2.5 to 15 yr of age) and three DMD carriers was studied using different specific anti-MHC MAbs. We also analyzed muscle fiber size and fiber reactivity with acridine orange and/or with a surface antigen marker. One-quarter of all fibers of DMD patients, or less with age, were of normal size and contained only adult slow MHC. Half of the muscle fibers contained adult and developmental MHCs. Only half of these fibers were representative of an active regenerative process. MHC co-expression also altered the proportion of normal fast or slow fibers. Adult fast MHCs were expressed as unique MHC only in small and very small fibers in the oldest DMD patients. In DMD carrier muscles, the greatest alterations in MHC expression were observed in patients with the most reduced dystrophin expression. However, MHC changes in dystrophin-positive fibers were similar to those observed in dystrophin-free fibers. In conclusion, disruptions or delays in the switching of all genes coding for adult fast and slow MHC and developmental MHC coincided with dystrophin deletion and with perturbations in its expression. 相似文献
105.
G.
berg B. Simonsson B. Smedmyr T. H. Ttterman P. Venge 《European journal of haematology》1987,38(4):356-362
Bone-marrow regeneration after chemo- and radiotherapy-induced aplasia can be monitored by serum levels of myeloperoxidase (MPO), lysozyme (LYS) and lactoferrin (LF). In 10 patients with leukemia, serum measurements were performed before and after bone-marrow transplantation. Bone-marrow regeneration was suggested by increments in serum MPO and LYS 5 and 4 days prior to the increase in mononuclear cells (Mono) and 10 and 9 d before the increase in polymorphonuclear leukocytes (PMN) in the peripheral blood. LF started to rise 4.5 d before detectable circulating PMNs. 2 patients with early relapses of leukemia post transplantation are shown to display atypical patterns of serum MPO and LYS. We conclude that serum measurements of MPO, LYS and LF may be used as early and sensitive means to monitor bone-marrow activity during hematological regeneration. However, the findings also strongly support the earlier proposal that MPO alone may be used to reflect myeloid activity in the bone-marrow in general. 相似文献
106.
The Usefulness of Magnetic Resonance Imaging in the Diagnosis of Anterolateral Impingement of the Ankle 总被引:3,自引:0,他引:3
LCDR Doug Duncan MD CAPT Tim Mologne MD CDR Hans Hildebrand MD Mark Stanley MD LT Richard Schreckengaust MD CAPT Dave Sitler MD 《The Journal of foot and ankle surgery》2006,45(5):304-307
The purpose of this study is to assess the sensitivity and specificity of magnetic resonance imaging (MRI) in the diagnosis of anterolateral impingement of the ankle and to assess the most helpful sequence in making the diagnosis. Twenty-four patients who had undergone ankle arthroscopy were chosen. Twelve patients had arthroscopically documented anterolateral impingement, and 12 patients with no impingement on arthroscopy served as controls. Two musculoskeletal radiologists and an orthopedic surgeon, blinded to the operative diagnosis, retrospectively reviewed selective MRI images in the sagittal, axial, and coronal planes. The sensitivities and specificities were calculated for all 3 reviewers. The Kendall coefficient of concordance was calculated for overall agreement among reviewers. Sensitivities varied from 0.75 to 0.83, whereas specificities varied from 0.75 to 1.00. Using the Fisher exact test of contingency, the sensitivities and specificities showed that all reviewers' interpretations were statistically significant with P = .039, .001, and .012, respectively. The axial images were felt to be most helpful in making the diagnosis. The physicians felt that the sagittal images were helpful in 67%, 83%, and 100%, respectively. MRI is a useful tool that can aid the clinician in the diagnosis of anterolateral impingement of the ankle. T1 sagittal images demonstrating displacement of the normal fat signal anterior to the fibula by scar can be useful and help to confirm the diagnosis. 相似文献
107.
Kohjirou Okahashi Kazuya Sugimoto Makoto Iwai Manabu Oshima Masayuki Samma Yoshiyuki Fujisawa Yoshinori Takakura 《Knee surgery, sports traumatology, arthroscopy》2006,14(6):542-545
The purpose of our study is to evaluate whether the hamstring tendons can regrow after harvesting for anterior cruciate ligament (ACL) reconstruction and whether the regenerate tissue can be histologically characterized as tendinous. Eleven of the patients (eight female and three male; mean age, 23 years; range 17–37 years) consented to participate in this study. One year after the ACL reconstruction, surgical biopsy was done. Regeneration of the tendon was detected macroscopically in 9 of the 11 patients. Histologically and immunohistochemically, the regenerated tendons closely resembled normal ones. The results of this study show the hamstring tendons can regenerate after harvesting for the ACL reconstruction. 相似文献
108.
目的:分析肛管松解加病理组织切除治疗陈旧性肛裂的疗效。方法:对l70例陈旧性肛裂病人采用裂口内直视下切断外括约肌皮下部和齿状线下内括约肌部分并修剪裂口、切除局部病理组织。结果:有效率为100%,治愈168例(98.8%),好转2例(1.2%)。结论:肛管松解加病理组织切除治疗陈旧性肛裂是一种安全可靠的治疗方法。 相似文献
109.
目的探讨多层螺旋CT(MSCT)肺密度测定对结缔组织病(CTD)肺间质病变(ILL)早期诊断的临床意义。方法对222例CTD患者及50名正常对照者,应用MSCT附带的Pulmo自动评估软件进行上、中、下肺区的密度测定,并同时进行肺高分辨扫描(}-IR(_1、),分析二者的变化与CTD伴ILL的关系。结果222例cm患者中197例平均肺密度有不同程度的增高,25例平均肺密度正常。157例HRCT有不同程度的肺间质病变,65例HRCT正常。50名正常对照者HRCT均正常,8名平均肺密度有不同程度的增高,42名平均肺密度正常。结论采用MSCT与HRCT对CTD伴ILL的检测结果差异有统计学意义,P=0.000(双侧),因此MSCT平均肺密度测定对早期诊断CTD伴ILL比HRCT更敏感,更有临床意义。 相似文献
110.
Solitary fibrous tumors (SFT) have recently been established to be of mesenchymal origin. Although there are numerous reports
of SFTs arising from the pleura, reports of the tumor arising from extrapleural sites are comparatively rare [Fletcher CDM,
Unni K, Mertens F (eds) World Health Organization classification of tumors, pathology & genetics, tumors of soft tissue and bone. IARC Press, Lyon, pp 86–901, 2002]. We report a case of SFT arising in the inguinal region. 相似文献