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61.
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   
62.
Graded porous titanium coatings have been deposited on titanium substrates for dental implants by plasma spraying in an argon atmosphere. X-ray diffraction (XRD), scanning electron microscopy (SEM), surface roughness measurement, and tensile strength tests were performed on graded porous coatings. The results showed that Ti(3)O(5) was formed in the outermost surface of the porous coatings due to oxidation. The graded porous coatings consisted of three layers. The outer layer was full of macropores with a surface roughness of approximately 100 microm. The diameter of many macropores reached and even surpassed 150 microm, which could be beneficial for tissue to grow into the coating. The middle layer consisted of a mixture of micropores and macropores. The inner layer was a very dense and tight interface layer that included mechanical, physical, and metallurgical bonding. In tensile strength tests, testing bars peeled off the coatings, because the adhesive agent fractured, but the coatings remained intact.  相似文献   
63.
Pan J  Zhang M  Wang J  Wang Q  Xia D  Sun W  Zhang L  Yu H  Liu Y  Cao X 《Immunology letters》2004,94(1-2):141-151
Maturation of dendritic cells (DC) is critical for efficient antigen presentation and initiation of an immune response. Interferon-gamma (IFN-gamma) is an important Th1 cytokine. In this study, we investigated the role of IFN-gamma in DC maturation using either IFN-gamma receptor deficient- or IFN-gamma overexpression-models. We showed that immature DC generated in vitro from bone marrow (BM) progenitor cells produced low level of IFN-gamma. After LPS stimulation, DC produced more IFN-gamma, and IFN-gamma productions were at comparable levels among C57BL/6 mice-derived DC (C57BL/6 DC), wild-type 129 mice-derived DC (129 DC) and IFN-gamma receptor deficient 129 mice-derived DC (IFN-gammaR-/-DC). We found that IFN-gammaR-/-DC exhibited decreased expression of CD54, CD86, reduced capacity to secrete IL-1beta and IL-12p70, and impaired capacity to stimulate alloreactive T cells and to drive Th1 differentiation. Transfection of IFN-gamma gene into DC promoted DC to express higher CD40, CD54, CD80, CD86, CCR7 and I-Ab, secrete more IL-1beta and IL-12p70, and more potently activate both CD4 and CD8 T cells. These data suggest that IFN-gamma signaling pathway is important for the maturation of DC in an autocrine fashion.  相似文献   
64.
The intent of the present study was to use chemical or electrical stimulation of cerebellar afferents to determine how different stimulation paradigms affect the pattern of activation of different populations of neurons in the cerebellar cortex. Specifically, we analyzed immediate changes in neuronal activity, identified neurons affected by different stimulation paradigms, and determined the time course over which neuronal activity is altered. In the present study, we used either systemic (harmaline) or electrical stimulation of the inferior cerebellar peduncle (10 and 40 Hz) to alter the firing rate of climbing and mossy fiber afferents to the rat cerebellum and an antibody made against the proto-oncogene, c-fos, as a marker to identify activated neurons and glia. In control animals, only a few scattered granule cells express nuclear Fos-like immunoreactivity. Although no other cells show Fos-like immunoreactivity in their nuclei, Purkinje cells express Fos-like immunoreactivity within their somatic and dendritic cytoplasm in control animals. Within 15 min of chemical or electrical stimulation, numerous granule and glial cells express Fos-like immunoreactivity in their nuclei. Cells in the molecular layer express Fos-like immunoreactivity following harmaline stimulation in a time and lobule specific manner; they do not appear to be activated in the electrical stimulation paradigm. Following harmaline injections, there is an initial loss of Fos-like immunoreactivity in the cytoplasm of Purkinje cells; 90 min later, nuclear staining is observed in a few scattered Purkinje cells. Following electrical stimulation, the cytoplasmic staining in Purkinje cells is enhanced; it is never present in the nucleus. Data derived from this study reveal cell-specific temporal and spatial patterns of c-Fos activation that is unique to each paradigm. Further, it reveals the presence of an activity dependent protein in the cytoplasm of Purkinje cell somata and dendrites.  相似文献   
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In order to evaluate the significance of the sinus node function test by transvenous atrial pacing in the diagno,sis of sick sinus syndrome (SSS), sinus node recovery time (SRT), co]rrected sinus node recovery time (CSRT) and total atrio- sinus and sino-atrial conduction time (SACT) are observed in 69 patients including non-SSS group 39 cases and SSS group 30 cases. According to our data, we suggest criteria for sinus node dysfunction as follows. SRT>1,400 ms and/or A-V junctional esca.pe before sinus recovery and;or secondary pause, CSRT>560 ms. total SACT>300 ms. With l item abnormal, the false positive rat.e in the non-SSS group is 7.7c7。 and the false negative rate in the S.SS group 3.30i" with 2 items abnormal, the false positive rate in the non-SSS group Oi and the false negative rate in the SSS grOiup 6.7'70. Atropine test results are compared with that of atrial pacing, 95.8To and 84.2% are compatible with each other in these 2 groups. In order to cut the use of invasive technic to the minimum, we propose performing the atropine test first. Only in those with unexplainable test results should the trial pacing test. be resorted to..  相似文献   
68.
BackgroundOpioid overdose-related deaths have increased dramatically in recent years. Combating the opioid epidemic requires better understanding of the epidemiology of opioid poisoning (OP) and opioid use disorder (OUD).ObjectiveWe aimed to discover geospatial patterns in nonmedical opioid use and its correlations with demographic features related to despair and economic hardship, most notably the US presidential voting patterns in 2016 at census tract level in New York State.MethodsThis cross-sectional analysis used data from New York Statewide Planning and Research Cooperative System claims data and the presidential voting results of 2016 in New York State from the Harvard Election Data Archive. We included 63,958 patients who had at least one OUD diagnosis between 2010 and 2016 and 36,004 patients with at least one OP diagnosis between 2012 and 2016. Geospatial mappings were created to compare areas of New York in OUD rates and presidential voting patterns. A multiple regression model examines the extent that certain factors explain OUD rate variation.ResultsSeveral areas shared similar patterns of OUD rates and Republican vote: census tracts in western New York, central New York, and Suffolk County. The correlation between OUD rates and the Republican vote was .38 (P<.001). The regression model with census tract level of demographic and socioeconomic factors explains 30% of the variance in OUD rates, with disability and Republican vote as the most significant predictors.ConclusionsAt the census tract level, OUD rates were positively correlated with Republican support in the 2016 presidential election, disability, unemployment, and unmarried status. Socioeconomic and demographic despair-related features explain a large portion of the association between the Republican vote and OUD. Together, these findings underscore the importance of socioeconomic interventions in combating the opioid epidemic.  相似文献   
69.
目的:总结皮下通道型胆囊肝胆管成形术的临床效果。方法:统计了1994年以来我院76例行STHG手术患者的适应症、临床效果及术后早期并发症。并选择同期实施的125 列行传统胆肠吻合(CJ)的患者进行对照。结果:STHG的手术适应症与传统胆肠吻合基本相同;STHG组患者的手术时间、住院时间、术中出血量明显少于CJ组,术后恢复良好,仅2例次并发症。结论;该术式既保存了胆囊及Oddi括约肌功能,又保证了胆汁的生理流向;防止了肠液的反,所以避免了消化功能紊乱,防止了反 流性胆管炎,对患者的影响小,是一种较为理想的治疗肝胆管结石和肝门胆管狭窄的术式。  相似文献   
70.
目的:观察雷尼替丁与复方丹参联合治疗急性胰腺炎的疗效。方法:对确诊急性胰腺炎65例随机分成治疗组35例,对照组30例,分别用常规治疗,常规治疗加雷尼替丁与复方丹参静滴,连用4-7天,评价其疗效。结果:治疗组与对照组显效率分别为85.71%、43.3%,两组差异显著,P<0.05。结论:两药联合应用不仅可减轻本病的炎症病变,且可改善心肌细胞营养状况。  相似文献   
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