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31.
碱性成纤维细胞生长因子(bFGF)加速猪背部创伤修复的实验研究 总被引:30,自引:0,他引:30
实验采用猪背部创伤模型,观察重组的碱性成纤维细胞生长因子(bFGF)对创伤修复的作用。在无菌条件下用特制打孔器在猪背部切割皮肤,形成2.5cm2的园型创面。将150个创面分成5组,分别以bFGF(60u/cm2创面),bFGF((60u/cm2创面)加SD-Ag、SD-Ag、生理盐水以及不治疗等方法处理,每间隔一天换药一次。实验结果表明,bFGF具有显著促进肉芽组织生长、加速创面再上皮化率以及增加创面愈合组织抗张力强度等作用。FGF显著促修复效应的确切机制尚不完全清楚,可能包括直接与间接效应两方面。 相似文献
32.
蚓激酶生物活性检测方法的研究 总被引:8,自引:1,他引:7
本文采用组织纤溶酶原激活剂(TPA)─纤维蛋白平板法测定蚓激酶的生物活性。该法操作简便,易于观察,重现性好。 相似文献
33.
LINDA C PADGETT GE-MING LUI ZENA WERB MATTHEW M LAVAIL 《Experimental eye research》1997,64(6):927-938
Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) play an essential role in both normal and pathological extracellular matrix degradation, and a TIMP has been associated with at least one type of retinal degeneration. We have studied expression of MMP-2 and TIMP-1 by zymography, immunocytochemistry, and immunoblotting in the retinal pigment epithelium (RPE) from normal, aged and diseased retinas. MMPs and TIMPs were found in the rat RPE, interphotoreceptor matrix (IPM), and in media conditioned by human and rat RPE in culture. In other polarized cells, MMPs and TIMP-2 are secreted vectorially towards the basal lamina. In the RPE, however, MMP-2 and TIMP-1 were secreted preferentially from the apical surface, the surface bordering the IPM. These findings provide new evidence that MMPs and TIMPs could play a role in the turnover of IPM components.Cell homogenates and conditioned media from RPE isolated from mutant Royal College of Surgeons (RCS) rats with inherited retinal dystrophy had similar amounts of MMP-2 and TIMP-1 as those from congenic control rats. The secretion of MMP-2 and TIMP-1 from RPE cell cultures isolated from young and aged human donors varied widely. However, with increasing cell passage number, secretion of MMPs and TIMPs from human RPE increased dramatically. Also, growing human RPE on bovine corneal endothelial cell-generated extracellular matrix instead of plastic reduced the secretion of both MMPs and TIMPs. These data suggest that the integrity of Bruch's membrane may serve to regulate RPE functions in MMP and TIMP secretion and that extracellular matrices contain signals that regulate MMP and TIMP synthesis and/or secretion by the RPE. 相似文献
34.
组织扩张术皮肤胶原的代谢改变 总被引:4,自引:0,他引:4
目的:研究常规扩张(ITE)和持续快速扩张(CTE)对皮肤胶原代谢的影响。方法用白色小家猪制作组织扩张术动物模型,用Gordeladze法测定血清和扩张组织的羟脯氨酸(HP)含量,藻酸盐印模材膜片法测量标记区面积;光镜测量真皮厚度。结果:ITE组血清HP含量升高,0.8倍,CTE组升高1.2倍,ITE和CTE组皮肤含量与正常皮肤相同,组织中HP总量均明显升高,持续扩张皮瓣组(CTEF)术后4wk皮 相似文献
35.
A. P. Dei Tos Paola Dal Cin 《Virchows Archiv : an international journal of pathology》1997,431(2):83-94
Soft tissue tumours represent a heterogeneous group of mesenchymal lesions, and their classification is the subject of continuous
debate. Chromosome analysis, molecular cytogenetics and molecular assays may become increasingly useful in diagnosis, and
this review summarises advances in the cytogenetic characterisation and classification of soft tissue tumours. Among the group
of fibrous lesions, superficial fibromatosis exhibits trisomy 8. This genomic change is also observed in desmoid fibromatosis
in association with trisomy 20. Trisomy 11 is the most frequently observed chromosomal aberration in congenital fibrosarcoma.
Dermatofibrosarcoma protuberans and giant cell fibroblastoma share a translocation t(17;22), which supports the concept of
the existence of a common differentiation pathway. Adipose tissue tumours is the group in which integration of genetics and
pathology has been most fruitful. Ordinary lipomas cytogenetically show an abnormal karyotype in about half the cases. Genomic
changes of the 11q13 region are observed in hibernoma. Lipoblastoma exhibits a specific 8q rearrangement in 8q11-q13. Loss
of material from the region 16q13-qter and 13q deletions are observed in spindle cell/pleomorphic lipomas. The well-differentiated
liposarcoma/atypical lipoma group is characterised karyotypically by the presence of one extra ring and/or extra giant chromosome
marker. Myxoid and round cell liposarcoma share the same characteristic chromosome change: t(12;16)(q13;p11) in most cases.
In the group of smooth muscle lesions most data are derived from uterine leiomyomas, which can be subclassified cytogenetically
into seven different types. Half of all leiomyomas are chromosomally normal; the other half have one of six possible consistent
chromosome changes. Alveolar rhabdomyosarcoma is characterised cytogenetically by two variant translocations t(2;13)(q35;q14)
and t(1;13)(p36;q14). Among tenosynovial tumours, the localised type of giant cell tumour of tendon sheath exhibits two different
karyotypic changes. One involves 1p11 in a translocation with chromosome 2 or with another chromosome. A second type involves
16q24. Synovial sarcoma is characterised cytogenetically by a translocation occurring between chromosome 18 and presumably
two adjacent loci on the X chromosome. In neural tumours, abnormalities of chromosome 22 have been reported in benign schwannomas
and perineuriomas. Malignant peripheral nerve sheath tumours exist in two main forms: sporadic and associated with the NF-1
syndrome. Karyotypes are very complex, but chromosomes 17q and 22q are very often involved. Clear cell sarcoma is characterised
cytogenetically and molecularly by a translocation t(12;22)(q13;q12). The Ewing’s sarcoma/peripheral neuroectodermal tumour
category shows a central karyotypic anomaly represented by the translocation t(11;22). The two variants t(21;22) and t(7;22)
are found in some cases. Among cartilaginous lesion, the most frequently described anomaly is the t(9;22)(q22;q12) in extraskeletal
myxoid chondrosarcoma. Intra-abdominal desmoplastic small round cell tumour is characterised by a t(11;22)(p13;q12).
Received: 5 February 1997 / Accepted: 24 February 1997 相似文献
36.
37.
The in vitro permeabilities of Caco-2 monolayers and permeabilities in tissue sections from colon of monkey, rabbit, and dog were compared using a series of compounds. The selected compounds differed in their physicochemical properties, such as octanol/water partition coefficient, water solubility, and molecular weight. Their structure included steroids, carboxylic acids, xanthins, alcohols, and polyethylene glycols. A linear permeability relationship was established between Caco-2 and colon tissue from both rabbit and monkey. The results suggest that Caco-2 is twice as permeable as rabbit and five times as permeable as monkey colon. However, no clear relationship could be established between Caco-2 monolayers and dog colon permeability. A relationship between permeability in Caco-2 monolayers and human absorption was found. The results suggest that within certain limits, permeability of Caco-2 monolayers may be used as a predictive tool to estimate human drug absorption. 相似文献
38.
Joseph Leighton 《Methods in Cell Science》1992,14(4):201-207
Summary Formation of epithelial tissues in culture so that they become facsimiles in their structure of such tissues in nature requires procedures that comply with several spatial imperatives: a) three-dimensional growth; b) histophysiologic conditions that provide, concurrently, gradients of maturation and of diffusion of metabolites; and c) growth as layers of cells without free edges. Many steps have been required in the evolution of these methods. Two systems are described here in sufficient detail to serve as a manual. Three-dimensional growth of masses of epithelial tissue is accomplished in matrix culture using Gelfoam sponge and collagen-coated cellulose sponge. Radial gradient culture, a recent development, provides conditions that comply with the requirements of histophysiologic gradients and of epithelial tissue growth in layers without interruption in their continuity. 相似文献
39.
The effects of training, immobilization and remobilization on musculoskeletal tissue 总被引:2,自引:0,他引:2
P. Kannus L. Jozsa P. Renström M. Järvinen M. Kvist M. Lehto P. Oja I. Vuort 《Scandinavian journal of medicine & science in sports》1992,2(4):164-176
Compared with the knowledge on immobilization, the effects of remobilization on musculoskeletal tissues have not been well established. What is sure is that remobilization and rehabilitation of any component of the musculoskeletal tissues require much more time than the time needed to cause the immobilization atrophy. With intensive rehabilitation, the functional properties of skeletal muscles can be improved significantly even years after the injury and following immobilization, but no study has shown whether full recovery is possible and whether these rehabilitated muscles are able to respond normally to further training. Experimental studies have given evidence that slow-twitch muscle fibres have better capacity for recovery than fast-twitch fibres, most likely due to better circulation and higher protein turnover. Also evidence has been given that fibre regeneration is possible through satellite cell activation and myotube formation. Very little is known, however, about the effects of age, gender or the level of preimmobilization muscle performance on the restoration capacity. Also the fate of the marked structural changes (for example, connective tissue accumulation) induced by immobilization is unknown. Tendon and ligament tissues are likely to respond appropriately to remobilization, resulting in acceleration of collagen synthesis and fibril neoformation. However, there is a strong suspicion that remobilized tendons and ligaments will not achieve all the biochemical and biomechanical properties of their healthy counterparts. Specifically, the amount of weak type III collagen has been shown to be overrepresented in these tissues instead of mature, strong type I collagen. It is not known whether this is an important risk factor for ruptures during later activity. The effects of remobilization on muscle-tendon junction and proprioceptive organs are not known. It would not be surprising if the serious structural changes induced by immobilization were unrestorable. In the literature dealing with immobilization and remobilization, cartilage degeneration is always a major concern, because not only too strenuous training or immobilization, but also unskilful remobilization may activate this process leading finally to osteoarthrosis. Bone may be one of the best components of musculoskeletal tissues to respond to remobilization, probably because the immobilization atrophy of bone is largely quantitative (osteoporosis) only. The prerequisites for bony recovery are that the follow-up time is long enough (months) and that immobilization has not exceeded about 6 months, the time limit between active and inactive (irreversible) osteoporosis. Prevention of the atrophying effects of immobilization can be very successful if performed properly. According to present knowledge, there are many methods for the purpose, including preimmobilization training early, controlled mobilization; optimal positioning of the immobilized joint; muscular training during immobilization; early weightbearing; exercise with the nonimmobilized extremity; and electrical stimulation. Lots of education and information will be needed, however, before these methods are deeply rooted in the daily routines of the attending physicians, physical therapists, athletic trainers and other persons involved in the treatment of musculoskeletal problems. 相似文献
40.