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21.
Carlotta Castagnoli Claudia Trombotto Sabzima Ondei Maurizio Stella Maurizio Calcagni Gilberto Magliacani Simone Teich Alasia 《Burns : journal of the International Society for Burn Injuries》1997,23(7-8):565-572
In this study, skin-infiltrating cells were characterized in both the active and remission phases of post-burn hypertrophic scar biopstes. Immunohistochemistry examination of active phase samples showed an abundant presence of Langerhans cells, T cells, macrophages, a low presence of natural killer cells and the lack of B lymphocytes. In active hypertrophic scars T lymphocytes infiltrate deep into the superficial dermis and are also observed in the epidermis: CD3+ cells were present at about 222±107 per 0.25 mm2. In particular the analysis of lymphocyte subpopulations showed that CD4+ T cells predominate in the dermis as well as in the epidermis of active hypertrophic scars whereas CD8+ cells were less well represented (CD4/CD8 ratio is 2.06). This distribution was also shown in remission phase samples and in normotrophic scar specimens, although the lymphocyte number was significantly lower. Approximately 70 per cent of T lymphocytes present in the tissue involved in active phase hypertrophic scar samples were activated (positive with anti-HLA-DR and IL-2 receptor antibodies) which is significantly higher than remission phase hypertrophic and normotrophic scars, in which positivity was 40 and 38 per cent, respectively. Upon activation, the lesional lymphocytes release several cytokines, locally and transiently, that interact with specific receptors in response to different stimulation. Central to the immune hypothesis of hypertrophic scars is that some of the T-cell lymphokines act on keratinocytes, fibroblasts and other cell types to induce changes characteristic of these scars. The presence and close proximity of activated T lymphocytes and antigen-presenting cells of various phenotypes in both the epidermis and dermis of hypertrophic tissues provides strong circumstantial evidence of a local immune response. However, the manner in which T cells achieve and maintain their activated state in hypertrophic tissues in not yet known, and both antigen-dependent and independent mechanisms may contribute. 相似文献
22.
The ontogeny of seizure genesis within the inferior collicular cortex was characterized in rats ranging in age from 3 days old to adult. Brief electrical stimulation of the right inferior collicular cortex in 30-day-old rats evoked poststimulus wild running behavior that coincided with afterdischarge activity in the inferior collicular cortex but not in the adjacent occipital cortex. Similar electrical stimulation in 16-day-old rats produced poststimulus wild running and jumping behaviors, which also coincided with afterdischarge in the inferior collicular cortex. In 10- and 5-day-old rats, electrical stimulation of the inferior collicular cortex produced poststimulus locomotion and coincident afterdischarge activity, but unlike older rats the locomotor behaviors consisted of forelimb paddling, hindlimb treading, and rolling/curling movements of the torso. Identical behaviors can be electrically elicited in 3-day-old rats. Although many of the seizure characteristics appear to be similar among the different age groups, 5-day-old rats were more sensitive to low frequency stimulation than 16-day-old rats, who in turn were more sensitive than adult rats. Thus, the inferior collicular cortex is capable of generating seizure activity in rats as young as 3 days of age, providing a focal model of neonatal seizure genesis. 相似文献
23.
G. J. Breur M. D. Lapierre K. Kazmierczak K. M. Stechuchak G. P. McCabe 《Calcified tissue international》1997,61(5):418-425
In this study, we tested the hypotheses that (a) both the domain volume (volume of the cell and the matrix it has formed)
and matrix volume of juxtametaphyseal hypertrophic chondrocytes in the growth plate is tightly controlled, and that (b) the
domain volume of juxtametaphyseal hypertrophic chondrocytes is a strong determinant of the rate of bone length growth. We
analyzed the rate of bone length growth (oxytetracycline labeling techniques) and nine stereologic and kinetic parameters
related to the juxtametaphyseal chondrocytic domain in the proximal and distal radial and tibial growth plates of 21- and
35-day-old rats. The domain volume increased with increasing growth rates, independent of the location of the growth plate
and the age of the animal. Within age groups, the matrix volume per cell increased with increasing growth rates, but an identical
growth plate had the same matrix volume per cell in 21- and 35-day-old rats. The most suitable regression model (R
2= 0.992) to describe the rate of bone length growth included the mean volume of juxtametaphyseal hypertrophic chondrocytes
and the mean rate of cell loss/cell proliferation. This relationship was independent of the location of the growth plate and
the age of the animal. The data suggest that the domain volume of juxtametaphyseal hypertrophic chondrocytes, as well as the
matrix volume produced per cell, may be tightly regulated. In addition, the volume of juxtametaphyseal hypertrophic chondrocytes
and the rate of cell loss/rate of cell proliferation may play the most important role in the determination of the rate of
bone length growth.
Received: 2 December 1996 / Accepted: 24 March 1997 相似文献
24.
孙保祥 《山东医大基础医学院学报》2004,18(6):342-343
目的:探讨口腔径路曲安奈德蝶腭神经节封闭治疗变应性鼻炎的效果。方法:变应性鼻炎患者415例,男270例,女145例。用自制封闭针头于口腔径路行曲安奈德蝶腭神经节封闭术。结果:415例中,有效250例,好转63例,总有效率为99.5%。结论:经口腔径路用曲安奈德行蝶腭神经节封闭术是治疗变应性鼻炎的有效疗法。 相似文献
25.
符文琛 《工业卫生与职业病》1987,(1)
通过对冶金、锻造、铸造、陶瓷、纺织、印染、铁路、航运等行业的16个作业环境热环境参数和工人生理反应关系的调查,对现行的高温作业分级标准不足之处提出了一些看法,并认为IS0提出的热环境下机体反应的阈限值对我国亦是适宜的。经统计学分析发现,作业环境的计算温度和工人平均体温之间有明显相关(r=0.86)。不同气温下464名工人的主观感觉调查表明,35℃时100%的工人都有热或很热的感觉。 相似文献
26.
巢蛋白(nestin)在瘢痕疙瘩和增生性瘢痕中的表达 总被引:5,自引:2,他引:3
目的探讨巢蛋白(nestin)在瘢痕疙瘩和增生性瘢痕中的表达。方法采用免疫组织化学技术方法检测8例正常皮肤、7例扁平瘢痕、8例瘢痕疙瘩、8例增生性瘢痕中nestin^+细胞,计数分析nestin^+细胞在瘢痕疙瘩和增生性瘢痕中的表达。结果①nestin在8例正常皮肤组织中表皮基底细胞和棘细胞、汗腺、毛囊、皮脂腺、血管内皮细胞和7例成纤维细胞的胞浆中表达。nestin在扁平瘢痕、瘢痕疙瘩、增生性瘢痕组织中表皮基底细胞和棘细胞、血管内皮细胞和成纤维细胞的胞浆及残留的汗腺、毛囊、皮脂腺中表达。②瘢痕疙瘩和增生性瘢痕组织中nestin^+表皮细胞、nestin^+成纤维细胞和nestin^+血管内皮细胞的数量明显高于正常皮肤和扁平瘢痕(P〈0.05),而正常皮肤与扁平瘢痕组织中nestin^+细胞的表达差异无显著性(P〉0.05)。结论巢蛋白在瘢痕疙瘩和增生性瘢痕表皮、成纤维细胞和血管内皮细胞中表达增高提示瘢痕疙瘩和增生性瘢痕的过度增生可能与巢蛋白相关。 相似文献
27.
腹腔镜下幽门环肌切开术治疗小儿先天性肥厚性幽门狭窄50例报告 总被引:4,自引:2,他引:2
目的总结腹腔镜下幽门环肌切开术治疗小儿先天性肥厚性幽门狭窄的成功经验.方法2001年4月~2004年4月,应用腹腔镜下幽门环肌切开术治疗小儿先天性肥厚性幽门狭窄50例,年龄12~90 d,平均35 d.分别在左、右上腹各置入3 mm trocar,左侧trocar置入无损伤抓钳夹近幽门处胃壁,右侧trocar先后置入伸缩式幽门肌切开刀、剥离器和幽门分离钳,完成幽门环肌切开术.结果腹腔镜下完成手术48例,中转开腹2例,其中1例为术中发现幽门前瓣膜症,1例为幽门黏膜损伤,经开腹修补痊愈.手术时间15~45 min,平均25 min.术后6 h拔胃管,开始喂奶.3~5 d出院.42例术后随访3~6个月,平均4.5月,生长发育均恢复正常.结论丰富的开腹手术经验、熟练的腹腔镜操作技术、术中良好的麻醉和合适的手术器械是完成腹腔镜下幽门环肌切开术的保障. 相似文献
28.
Hypertrophic pachymeningitis is a rare fibrosing inflamatory process involving dura mater and tentorium. In this report we are presenting contrast enhanced MRI findings of an unusual case of pachymeningitis which presented with a periorbital mass due to dural sinuses occlusion and retrograde filling of periorbital veins through superior sagittal sinus. 相似文献
29.
Irwin S. Johnsrude William M. Bogey Jr Michael D. Tripp 《Cardiovascular and interventional radiology》1994,17(6):336-338
Discovery of a postlumbosacral discectomy fistula between the right iliac artery and vein was obscured by an associated severe stricture of the infrarenal inferior vena cava in a 49-year-old man. During venous stenting for treatment of peripheral edema, the fistula was suspected because of faint pulsatile right iliac vein flow and increased O2 saturation of the venous blood. The suspicion was confirmed on subsequent iliac arteriography. Surgical closure of the fistula with arterial interposition grafting was then performed. The patient improved substantially. 相似文献
30.
R. C. Read 《Hernia》2005,9(1):79-83
Preperitoneal, a word coined by Nyhus in the 1960s, has been applied not only to posterior approaches that he, Stoppa, and Wantz popularized but to anterior exposures of the groin, which divide the transversalis fascia. This assumes that all give similar views of the easily cleaved space of Bogros. However, accumulated anatomical observations reveal the transversalis fascia as having not one but two layers. The inferior epigastric vessels run between rather than in the preperitoneal space, which is avascular and has its own fascia lining the peritoneum. Historical evidence shows that both the midline Cheatle-Henry and lateral Ugahary-Kugel approaches, which transect the abdominal wall, provide excellent exposure of the avascular preperitoneal space. However, neither the unilateral posterior McEvedy approach nor the anterior approach does, as only part of the musculature and fasciae are retracted. The inferior epigastric vasculature and posterior lamina transversalis fascia, which remain in situ, block the view. Unless they are disrupted or circumvented, neither of the latter approaches or subsequent repairs should be labeled preperitoneal. 相似文献