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21.
Erich Stoelben Holger Harpering Joerg Haberstroh Antonio di Filippo Eckhard Wellens 《European journal of cardio-thoracic surgery》2003,23(1):15-20
INTRODUCTION: The successful use of cryopreserved tracheal allografts in canine models suggests their use in humans. The grade of genetic difference, the mechanism of revascularisation and the method of cryopreservation are not clearly defined. The purpose of our study was to investigate the rejection of tracheal transplants in a standardised heterotopic rat model using different forms of cryopreservation. METHODS: Tracheae from Brown Norway rats were implanted into the omentum from Brown Norway rats or Lewis rats. We transplanted fresh isografts or allografts and pretreated isografts or allografts. Cryopreservation was performed in a medium containing 10% dimethyl sulphoxide at -80 degrees C for 28 days (I) or -196 degrees C for 84 days (II) or without medium at -80 degrees C for 28 days (III). The transplants were excised after 7 and 21 days, respectively. RESULTS: Histological examinations revealed normal structure and function of isografts after 21 days. In the cryopreserved isograft, the epithelium had disappeared and the tracheal lumen was partially obstructed by a non-compact fibrous tissue. In the fresh allografts, the epithelium was replaced by aggressive fibrous tissue, infiltrating the membranous part of the trachea and occluding the tracheal lumen. The cartilage was vital without any sign of rejection. In the cryopreserved allografts, the tracheal lumen was obstructed by dense fibrous tissue with an inflammatory reaction. The cartilage of cryopreserved allografts (II) and (III) had lost the nuclei corresponding to non-vital tissue. Only in the cryopreserved allografts (I) did we find nodular regeneration at the edges of the cartilaginous bow. CONCLUSIONS: The heterotopic transplantation model allows the study of the mechanisms leading to tracheal obstruction. Cryopreservation was found to have no clear advantage in reducing transplant immunogenicity. Cryopreservation leads to significant damage to the cartilage, the intensity of which is dependent on the mode of cryopreservation. 相似文献
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目的 探讨他丁类降脂药是否具有改善高血压患者血管功能的作用。 方法 ~ 级轻中度高血压患者 5 5人 ,在常规抗高血压治疗的同时 ,加用氟伐他丁 (Flu) 2 0~ 4 0 m g/ d,并与 37例单纯常规抗高血压治疗病人对比。采用彩色多普勒超声检查肱动脉 (BA)和胫前动脉 (TA)的管腔内径。采用充血法测定血管内皮依赖性舒张功能 (Δ Dia- P)。 结果 Flu治疗 3个月 ,血脂水平明显下降 ,可见 TA血管 Δ Dia- P改善 (% :8.5 1± 3.0 7vs14 .19± 5 .4 1,n=6 ,P<0 .0 5 ) ,以后均维持在较高水平。治疗 3个月时 BA的 ΔDia- P也有改善 ,但未达统计学差异水平 ,治疗 12个月时 BAΔ Dia- P明显改善。多元逐步回归分析在所观察的参数中未发现和血管功能有固定关系的因素。 结论 Flu能够使接受常规降压药治疗的高血压患者的 Δ Dia- P改善。小剂量长时间的 Flu可以改善血管舒张功能。药物干预后 TA的功能变化出现较早 ,是反映血管功能变化的敏感靶点 相似文献
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Bone mineral content (BMC) and testosterone levels were evaluated and compared in 10 hypogonadal males and 10 normal, age-matched controls. In 6 of the subjects an investigation was also carried out into the effects of testosterone administration on lumbar BMC, calcitonin (CT) response to hypercalcaemia, osteocalcin (BGP) and the fasting urinary calcium/creatinine and hydroxyproline/creatinine ratios. Our results confirm that male hypogonadism is characterized by a low BMC and that testosterone administration is able to improve this parameter and to increase both basal BGP and CT response to hypercalcaemia. Testosterone therefore probably acts on bone tissue through both a direct action on osteoblast cells and an improvement in CT secretion. 相似文献
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Non-invasive treatment for retained common bile duct stones in patients with T tube in situ: saline washout after intravenous ceruletide 总被引:1,自引:0,他引:1
The combination of ceruletide-induced relaxation of the sphincter of Oddi plus flushing with saline has recently been proposed as a novel procedure for the treatment of residual common bile duct (CBD) stones. In this study we have administered intravenous ceruletide (2 ng kg-1 body weight min-1 for 1 h) plus intraductal saline (800-3000 ml, infused at a rate that kept biliary pressure below 30 cmH2O) to a group of 14 patients. The treatment induced the passage of residual stones in 11 subjects (79 per cent) with complete clearance in 7 (50 per cent). The majority of the cleared concretions (11/15) had a diameter less than 10 mm. No severe side-effects were recorded during the treatment. Four of the seven subjects who exhibited incomplete CBD clearance underwent a short cycle of mono-octanoin administration in order to reduce the size of residual radiolucent stones. This course of treatment was followed by another attempt with intravenous ceruletide and saline washout which gave a successful response in an additional three cases. These data indicate that the combination of ceruletide and flushing is a safe and inexpensive method for treatment of residual stones. The procedure is feasible for both radiolucent and radio-opaque stones and is mainly eligible for small concretions of diameter less than 10 mm. Larger (greater than 10 mm) radiolucent stones may be partially dissolved with mono-octanoin and then eliminated by the washout technique. 相似文献
28.
目的:介绍一种快速定量检测HBV DNA的方法及临床初步应用。方法:对40例乙型肝炎病毒表面抗原阳性的慢性乙型肝炎患者共79份血清标本,采用Digene第二代杂交捕获试验(Hybrid Capture Ⅱ,HCⅡ,v2.0)定量检测HBV DNA,并与分枝链DNA信号扩增试验(bDNA,v1.0)作比较。结果:79份HBsAg阳性血清中,HCⅡ检出HBV DNA57份(72.2%),bDNA法为45份(57%),HCⅡ敏感性略高于bDNA法;2种方法定量检测HBV DNA的符合率为85.9%,相关性良好(r=0.95);19例抗病毒治疗乙肝患者,治疗后平均HBV DNA载量下降2(Log10)数量级,6例发生e抗原血清转换的患者平均HBV DNA载量下降3(Log10)数量级以上,且HBV DNA阴转早于e抗原血清转换。结论:HCⅡ比bDNA更为简便、经济、快速,可用于临床HBV DNA水平的定量检测、监控及抗病毒药物的筛选、考核。 相似文献
29.
The effects of quercetin have been investigated on the gastrointestinal propulsion of charcoal meal in mice. Quercetin reduced the rate of intestinal transit and this effect was potentiated by verapamil. 相似文献
30.
K. Elekes L. Herndi J. E. Muren D. R. Nssel 《The Journal of comparative neurology》1994,341(2):257-272
In this study, antiserum raised against an insect myotropic peptide, leucokinin I (DPAFNSWGamide), was: used for mapping leucokinin-like immunoreactive (LK-LI) neurons in the gastropod mollusc, Helix pomatia. Immunocytochemistry performed on both whole-mounts and cryostat sections demonstrated LK-LI neurons in all ganglia of the central nervous system (CNS), except the visceral ganglion. Altogether about 700 immunolabelled neurons have been found, with nearly one-half (46%) in the cerebral ganglia. A large proportion of the LK-LI neurons have small cell bodies and are likely to be interneurons. The most prominent LK-LI cell group is represented by the entire neuron population of the mesocerebri, which is the major source of a thick fiber bundle system, encircling and innervating the whole CNS. One single LK-LI giant neuron was found, which is located in the left pedal ganglion and is termed GLPdLKC (giant left pedal leucokinin immunoreactive cell). This cell has not been identified previously. The ganglion neuropils are heavily innervated by varicose LK-LI fiber arborizations. Some integrative centers, such as the medullary neuropil of the procerebri, reveal an extreme density of LK-LI innervation. All major peripheral nerves contain a large number of LK-LI axons, and LK-LI innervation is found in the musculature of different peripheral organs (buccal mass, lip, tentacles, oviduct, intestine). Among the peripheral organs investigated, the intestine contains a rich varicose LK-LI network, composed of both intrinsic and extrinsic elements. Radioimmunoassay (RIA) demonstrates a very high content of LK-LI material in Helix ganglion extracts (about 50 pmol/CNS). This is the first report on the occurrence of a substance resembling the myotropic neuropeptide leucokinin I in a phylum outside arthropods. Based on our immunocytochemical observations, a role for leucokinin-like peptides in both central and peripheral regulatory processes in Helix is suggested. According to double-labelling experiments, only a small number of the LK-LI neurons are labelled with an antibody to the vertebrate tachykinin substance P. 相似文献