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91.
Calretinin is a calcium-binding protein expressed in different normal and neoplastic tissues. Early studies suggested that calretinin is a useful marker to differentiate adenocarcinomas from malignant mesotheliomas of the lung, but subsequent work has shown that calretinin can be expressed in several other tumor types. To systematically investigate the epidemiology of calretinin expression in normal and neoplastic tissues, we used tissue microarrays (TMAs) to analyze the immunohistochemically detectable expression of calretinin in 5233 tissue samples from 128 different tumor categories and 76 different normal tissue types. At least 1 case with weak expression could be found in 74 of 128 (58%) different tumor types and 46 entities (36%) had at least 1 tumor with strong positivity. In normal tissues, a particularly strong expression was found in Leydig cells of the testis, neurons of the brain, theca-lutein and theca interna cells of the ovary, and mesothelium. In tumors, strong calretinin expression was most frequently found in malignant mesotheliomas (6 of 7), Leydig cell tumors of the testis (5 of 5), adenomas of adrenal gland (5 of 9), and adenomatoid tumors (4 of 9). In summary, calretinin is frequently expressed in many different tumor types. Metastases of various different origins must be included in the differential diagnosis of calretinin-positive pleura tumors.  相似文献   
92.
The role of lymphocytes in the pathogenesis of lung fibrosis is not clear, but the weight of the evidence supports a pro-fibrotic effect for lymphocytes. The high-affinity interleukin-2 receptor (haIL-2R) is expressed on activated, but not quiescent, T lymphocytes. This selective expression of haIL-2R provides the basis for therapeutic strategies that target IL-2R-expressing cells. We hypothesized that elimination of activated lymphocytes by IL-2R-targeted chimeric proteins might ameliorate lung fibrosis. We investigated the effects of IL-2-Bax, a novel apoptosis-inducing IL-2R-targeted chimeric protein, on bleomycin-induced lung injury in mice. Treatment groups included (i) a single intratracheal instillation of bleomycin and twice-daily intraperitoneal injections of IL-2-Bax; (ii) intratracheal bleomycin and intraperitoneal IL-2-PE66(4Glu), an older-generation chimeric protein; (iii) intratracheal bleomycin/intraperitoneal PBS; (iv) intratracheal saline/intraperitoneal PBS. Lung injury was evaluated 14 days after intratracheal instillation by cell count in bronchoalveolar lavage (BAL) fluid, semi-quantitative and quantitative histomorphological measurements and by biochemical analysis of lung hydroxyproline. Bleomycin induced a BAL lymphocytosis that was significantly attenuated by IL-2-Bax and IL-2-PE66(4Glu). However, morphometric parameters and lung hydroxyproline were unaffected by the chimeric proteins. These results show that IL-2-Bax reduces the lymphocytic infiltration of the lungs in response to bleomycin, but this effect is not accompanied by a decrease in lung fibrosis.  相似文献   
93.
气管组织工程的研究策略及其展望   总被引:1,自引:0,他引:1  
气管组织工程是近10年来国内外研究的热点和难点问题,取得了一些进展.但如何更好地遴选基质材料、实现种子细胞共培养、上皮化以及再血管化来构建组织工程化气管仍需要不断寻求新的研究思路和策略.本文从气管重建和理想化气管替代物的角度,回顾了近年来在组织工程气管方面的研究进展,并对未来的研究作出展望.  相似文献   
94.
Summary We describe a purification method for tissue culture-grade trypsin that yields an enzyme mixture with reproducible activities of trypsin, elastase, and chymotrypsin and eliminates amylase and lipase.  相似文献   
95.
碱性成纤维细胞生长因子 (b FGF)是近年来研究较为广泛的生长因子之一 ,对骨组织有着广泛的生物学效应。本文就 b FGF的研究进展及其目前在骨组织工程学研究方面的应用做一综述  相似文献   
96.
The PTEN/MMAC1 ( PTEN ) gene was identified as a tumor suppressor gene encoding a cytoplasmic protein that controls cellular processes. To investigate the potential role and the alteration of the PTEN gene in soft tissue sarcomas (STSs), we searched for homozygous deletion and promoter hypermethylation in a series of 48 STSs that was composed of malignant fibrous histiocytoma, leiomyosarcoma, malignant peripheral nerve sheath tumor, including 2 cases with a mutation that we previously reported; differential polymerase chain reaction and methylation-specific polymerase chain reaction, respectively, were used for the analyses. Furthermore, to determine whether PTEN gene alterations are involved in the down-regulation of PTEN expression, we examined the expression of PTEN protein in 38 cases in which paraffin-embedded tissues were available for immunohistochemical analysis. In addition to our previous results showing that 2 (4%) of 51 cases had a PTEN mutation, promoter methylation was recognized in 6 (13%) of 48 cases, and homozygous deletion was detected in 1 (2%) of 48 cases in the current study. Of 6 cases with promoter methylation of PTEN gene, 5 were malignant peripheral nerve sheath tumor. Decreased expression of PTEN protein was recognized in 11 (29%) of 38 STS cases. Of 9 cases with PTEN alterations (6 cases with promoter methylation, 2 with mutation, and 1 with homozygous deletion), 3 (33%) showed decreased expression of PTEN protein. Furthermore, decreased expression of the PTEN gene showed a statistically significant correlation with high MIB-1 labeling index in 38 STS cases examined ( P = .0441). In conclusion, promoter methylation and homozygous deletion of the PTEN gene were found to be relatively rare events in cases of STS, as is mutation of the gene. Of 9 cases with a PTEN alteration, 3 (33%) showed a decrease in PTEN expression, indicating that PTEN gene alterations seem to play a minor role in the inactivation of PTEN in these tumors. Furthermore, although a further detailed analysis of a larger number of cases is still necessary, the present results suggest that PTEN expression may be a useful indicator of cell proliferation in patients with STS.  相似文献   
97.
远端蒂腓肠神经营养血管皮瓣与肌皮瓣的临床应用与改进   总被引:6,自引:0,他引:6  
目的:报道应用远端蒂腓肠神经营养血管皮瓣,肌皮瓣修复小腿下段及足踝部软组织缺损的可行性安全性和临床效果。方法:对42例以远端蒂腓肠神经营养血管(肌)皮瓣修复小腿下段及足踝部不同原因所致软组织缺损病例进行总结分析。本组男36例,女6例;年龄最大75岁、最小6岁;皮瓣最大面积17.0cm×15.0cm,最小6.0cm×5.0cm,其中12例皮瓣面积在10.0cm×10.0cm以上;6例设计为肌皮瓣(腓肠肌外侧头),肌瓣最大为10.0cm×7.0cm×2.0cm,最小为6.0cm×5.0cm×1.0cm。结果:所有病例术后皆出现不同程度的皮瓣肿胀,暗道较明道者明显。2例大皮瓣经行小隐静脉远端结扎仍出现肿胀、色暗,皮瓣近侧1/3坏死。皮瓣边缘坏死3例,换药治愈。部分坏死需行植皮者3例。36例术后伤口I期愈合,骨外露软件组织缺损覆盖修复满意,6例II期愈合,其中糖尿病,地中海贫血各一例。结论:(1)远端蒂腓肠神经营养血管皮瓣转位修复小腿下1/3及足踝部缺损创面,极有临床实用价值;(2)设计切取腓肠神经营养血管肌皮瓣修复小腿及足踝填充感染创腔是可行的;(3)但对其皮瓣及所携带的肌瓣究竟切取多大面积是安全的、肌瓣的血运机理以及远端蒂筋膜皮瓣中小隐静脉干是否结扎,何处结扎等问题仍有待进一步研究。  相似文献   
98.
Many diseases associated with complement activation are characterized by tissue deposition of components of the terminal complement complex (TCC). The ninth component of complement (C9) plays an important role in the cytolytic effects, and may contribute to the non-lethal cell-regulating functions of the TCC. In this study we examined the behaviour of radiolabelled human C9 and its soluble complexed form SC5b-9 in vivo in order to determine the effects of complement activation on its turnover, distribution and molecular size. In normal rabbits the metabolic parameters of 125I-C9 (median and range) were: plasma half-life (t1/2) 25.9 (20.6-29.5) h, fractional catabolic rate (FCR) 5.7 (5.3-7.0)%/h, and extravascular/intravascular ratio (EV/IV) 0.7 (0.6-1.1). The distribution of radiolabelled C9 amongst body tissues was similar to that observed for rabbit serum albumin (RSA). Activation of the complement cascade with i.v. injection of cobra venom factor (CVF) resulted in rapid disappearance of C9 from the plasma and accumulation of protein-bound radiolabeled in the spleen (exceeding the plasma concentration) and the liver. RSA metabolism and distribution were unaffected by CVF. Fine performance liquid chromatography (FPLC) gel filtration of plasma samples suggested that monomeric C9 was the only major radiolabelled protein present during normal turnovers, whereas CVF administration was accompanied by the prompt appearance of a high mol. wt species consistent in size with SC5b-9. When injected directly, 125I-SC5b-9 disappeared rapidly from the plasma, falling by 50% in 0.7 (0.6-0.8) h, and less than 15% remaining after 4 h with accumulation of protein-bound label in the spleen and liver. These results demonstrate the complexity of C9 metabolism during complement activation.  相似文献   
99.
肢端黏液样炎性纤维母细胞肉瘤2例及文献复习   总被引:1,自引:2,他引:1  
目的探讨肢端黏液样炎性纤维母细胞肉瘤的临床病理学特征及鉴别诊断。方法对2例发生在下肢末端的黏液样炎性纤维母细胞肉瘤进行光镜观察和免疫组化标记,并复习文献。结果2例发生在下肢末端的病程较长的渐进性肿块,术后局部复发。镜检:病变呈多结节状,边界不清;黏液样基质中见数量不等的各类炎细胞浸润,散在或灶性分布梭形、奇异形和多空泡状脂肪母细胞样3种形态的瘤细胞。免疫表型:肿瘤细胞Vim弥漫阳性,CD68和CD34灶性阳性,CK、SMA、HHF-35、S-100蛋白、CD45、CD45R0、CD15、CD30均阴性。结论此病病程较长,术后易局部复发,是一种低度恶性的肿瘤。鉴于病变黏液样基质及各类炎细胞浸润的背景较为突出,而特征性的瘤细胞稀疏,应注意与炎症性病变或具有相似组织形态的良性或恶性肿瘤鉴别。  相似文献   
100.
The clinical applications of theoretical immunology are not numerous. The authors demonstrate present-day immunocytotherapeutic approaches to fetal tissue transplantation widely used in medicine. Results of therapy by injections of lymphokine-activated killer cells in combination with interleukin-2, T-cell vaccines, and genetically transformed T cells are presented. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N o 4, pp. 412–415, April, 1994  相似文献   
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