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1.
Sharada Sivaram Kalavakolanu 《Journal of the Saudi Heart Association》2015,27(3):206-209
We report a case of a young male presenting as Restrictive cardiomyopathy, refractory heart failure and syncope due to typical right atrial flutter complicating hypertrophic cardiomyopathy.Successful catheter ablation of the flutter promptly ameliorated the congestive failure with resolution of restrictive physiology. 相似文献
2.
Ung-il Chung Hiroshi Kawaguchi Tsuyoshi Takato Kozo Nakamura 《Journal of orthopaedic science》2004,9(4):410-414
Mammalian bones have three distinct origins (paraxial mesoderm, lateral plate mesoderm, and neural crest) and undergo two different modes of formation (intra-membranous and endochondral). Bones derived from the paraxial mesoderm and lateral plate mesoderm mainly form through the endochondral process. During this process, hypertrophic chondrocytes play a vital role in inducing both osteogenesis and angiogenesis. One of the essential osteogenic factors secreted from hypertrophic chondrocytes is Indian hedgehog (Ihh). In contrast, bones derived from the neural crest mainly form through the intramembranous pro-cess and do not require Ihh. Thus, depending on their origin, bones have distinct signaling properties, which need to be considered in the research and application of bone biology.Presented at the 18th Annual Research Meeting of the Japanese Orthopaedic Association, Kitakyushu, Japan, October 17, 2003 相似文献
3.
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
4.
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
5.
Boris M Petrikovsky Steven Ravens 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2002,6(2):175-177
INTRODUCTION: The change in obstetrical practices over the last decade in favor of trials of labor in patients with uterine scars has resulted in increased incidences of uterine ruptures. Although neither repeat cesarean delivery nor a trial of labor is risk free, evidence from a large multicenter study shows vaginal birth after the cesarean (VBAC) is associated with shorter hospital stays, fewer postpartum blood transfusions, and a decreased incidence of postpartum maternal fever. The uterine rupture remains the most serious complication associated with VBAC. Factors associated with uterine rupture include excessive exposure to oxytocin, dysfunctional labor, and a history of more than 1 cesarean delivery.2 Because uterine rupture may be a life-threatening event, intrapartum surveillance and the ability to perform an emergency surgery are both necessary when trial of labor is allowed. Until now, no early symptoms pathognomonic to uterine rupture had been described. We share our experiences with the novel approach to the problem - an intrapartum endoscopy. MATERIALS AND METHODS: Endoscopic examination was accomplished by using the intraoperational fiberscope (Olympus and Endoview system (Costa Mesa, CA, USA). A gas-sterilized 25-cm long fiberscope is introduced into the amniotic cavity through the cervical canal after rupture of the membranes. The distance between the fiberscope and the object varies from 3 to 50 mm. The fiberscope has a separate channel for the fluid infusion (normal saline) throughout the procedure; the surgeon looks through the eyepiece directly and exhibits control over the flexible scope. The duration of endoscopy is less than 15 minutes. The inserting of the endoscopic device is very similar to that of insertion of an intrauterine pressure catheter. The IRB Committees of both participating institutions approved the study protocol. Twenty-eight patients with an unknown or poorly documented site of the uterine scar were included in the study. An ultrasound examination had been performed on all patients prior to endoscopy to assess fetal wellbeing and placental location. The ages of the patients ranged from 21 to 38 years. Eighteen women had 1 previous cesarean delivery, and 10 had 2. The performance of intrapartum endoscopy did not interfere with fetal monitoring; 21 fetuses were monitored externally, 7 internally. Indications for previous cesarean deliveries were as follows: fetal distress in 11 cases, failure to progress in labor in 8, placenta previa in 2, and unknown in 7. Twenty-one patients delivered vaginally; 7 had had repeat cesarean deliveries. All neonates were born in satisfactory condition. The Apgar scores at 1 minute varied from 7 to 9 and at 5 minutes from 8 to 10. The integrity of the uterine wall was assessed by manual postpartum uterine exploration in each case of vaginal delivery and by visualization and palpation of the scar site in each abdominal delivery. RESULTS: The lower uterine segment and contractile portion of the anterior uterine wall were visualized successfully in all patients. In 25 patients, the presumed scar site looked totally indistinguishable from the rest of the lower uterine segment and anterior uterine wall. Two scars were identified as vertical in 2 patients who were delivered by a repeat abdominal operation. A vertical scar appears as a groove running in a cephalad-caudad direction from the lower uterine segment into the contractile portion of the anterior uterine wall. The usefulness of the intrapartum endoscopy is best demonstrated by the following case reports (2 of 28 study cases). 相似文献
6.
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
7.
ABSTRACT: Fractional resurfacing is gaining acceptance as a preferred method for skin resurfacing. Experience in treating photoaging, acne scars, and melasma is reviewed. 相似文献
8.
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
9.
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
10.
目的 探讨肿泡眼单睑患者的理想重睑成形术式。方法 针对肿泡眼单睑的解剖特点 ,对常规切开法重睑成形术加以改进。通过较窄重睑线设计 ,去除适量松弛皮肤 ,去除臃肿眶隔脂肪及肥厚眼轮匝肌、睑板前结缔组织 ,改善重睑形态。结果 本组患者共 30 8例 ,随访 15 0例 ,随访时间 3~ 12个月。其中 12 3例效果满意 ,19例效果一般 ,8例不甚满意。结论 对于肿泡眼患者可在切开法重睑成形术的基础上 ,将松弛皮肤、眶隔脂肪、眼轮匝肌及睑板前结缔组织适量去除 ,术后重睑形态自然流畅 相似文献