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81.
本文综述了新型长效雌三醇衍生物-尼尔雌醇的药理作用、代谢动力学、防治绝经后骨质疏松症和血脂紊乱实验及临床研究的进展。 相似文献
82.
本文总结了14例应用刮治和自体骨移植术治疗大型牙源性角化囊肿的方法,14例植骨均成活,4例术后囊肿复发,再次手术,指出:与骨断切除治疗大型角化囊肿的方法比较,此法最大的优点是有利于保持患者面容和咀嚼功能,并对大型角化囊肿的手术原则,自体骨移植问题及手术注意事项进行了讨论。 相似文献
83.
The role of cytokines in rhinosinusitis 总被引:1,自引:0,他引:1
Since the last decade, new insights into inflammatory processes have become possible by investigating the pattern of cytokines in acute and chronic sinus diseases. This review aims to update and discuss the findings of in vitro and in vivo studies concerning the role of cytokines in sinusitis and nasal polyposis. The proinflammatory cytokines interleukin-1beta, interleukin-6 and the neutrophil-chemoattractant interleukin-8 may play a major role in acute sinusitis, as shown in viral and allergic rhinitis. In chronic sinusitis interleukin-3 dominates the cytokine profiles, giving support to a variety of inflammatory cells. Interleukin-5 is a key protein in the pathogenesis of nasal polyposis. Activation and survival of eosinophils in nasal polyps are thought to be regulated by interleukin-5. Further investigation of cytokine expression patterns in inflammatory sinus diseases will lead to a better understanding of their pathogenesis and to a development of new therapeutic modality. 相似文献
84.
Genetic imbalances in pleomorphic xanthoastrocytoma detected by comparative genomic hybridization and literature review. 总被引:2,自引:0,他引:2
Xiao-Lu Yin Angela Bik-Yu Hui Eleanore C Liong Min Ding Alex R Chang Ho-Keung Ng 《Cancer Genetics and Cytogenetics》2002,132(1):14-19
Pleomorphic xanthoastrocytoma (PXA) is a rare, low-grade astrocytic tumor found in the central nervous system. Histologically, the tumor is characterized by markedly pleomorphic and lipidized cells. Although most of the patients have a favorable prognosis, a small number of cases undergoing recurrence or progression to anaplastic astrocytoma were reported. Very few genetic studies have been performed on PXA because of its rarity and the pathogenesis of this neoplasm is largely unknown. In order to provide an overview of genetic alterations in PXA, we performed comparative genomic hybridization to identify chromosomal imbalances (DNA gains and losses) in three cases of PXA. Genetic imbalance was detected on at least one chromosome for each case. One case, which revealed multiple genetic alterations, showed a poor prognosis. DNA gain on chromosome 7 and loss on 8p were demonstrated in two of three cases, suggesting that the candidate gene(s) located on these regions may play a role in the development of PXA. Further studies are needed to identify the residing candidate genes that are involved in the tumorigenesis of PXA. In addition, the histopathological features and previous genetic studies on PXA are reviewed. 相似文献
85.
Association of MICA polymorphism with HLA-B51 and disease severity in Korean patients with Behcet's disease 总被引:1,自引:0,他引:1
Park SH Park KS Seo YI Min DJ Kim WU Kim TG Cho CS Mok JW Park KS Kim HY 《Journal of Korean medical science》2002,17(3):366-370
The HLA-B51 allele is known to be associated with Behcet's disease (BD) in many ethnic group. However, it has not yet been clarified whether the HLA-B51 gene itself is the pathogenic gene related to BD or whether it is some other gene in linkage disequlibrium with HLA-B51. Recently, the Triplet repeat (GCT/AGC) polymorphism in transmembrane region of the MHC class I chain-related A (MICA) gene was identified. To investigate the association of MICA with BD, we studied the MICA polymorphism in 108 Korean BD patients and 204 healthy controls in relation to the presence of HLA-B51 and clinical manifestations. The triplet repeat polymorphism was determined by polymerase chain reaction (PCR)-denaturing polyacrylamide gel electrophoresis (PAGE). The phenotype frequency of the MICA*A6 allele (relative risk, RR=2.15, p=0.002) and HLA-B51(RR=1.87, p=0.022) were significantly increased in the Korean patients with BD. A strong linkage disequilibrium was observed between the MICA*A6 and HLA-B51 in both the patients with BD and control subjects. Stratification analysis showed that MICA*A6 homozygosity was strongly associated with BD in the HLA-B51-negative population, and HLA-B51 was also associated with MICA*A6-negative population. In conclusion, MICA*A6 rather than HLA-B51 was strongly associated with Korean patients with BD, and the MICA*A6 allele is a useful susceptibility marker of BD, especially in the HLA-B5-negative 相似文献
86.
Cai Guoping Lian Jie Shapiro Sandor S. Beacham Dorothy A. 《Methods in Cell Science》2000,22(2-3):107-114
In this study we introduce a novel in vitro 'oil-drop' assay system for the measurement of endothelial cell (EC) migration, based on the original concept of the Teflon fence assay (Pratt et al., 1984; Am. J. Pathol. 117: 349–354). An aliquot of 15–20,000 human umbilical vein EC (HUVEC) is pipetted through a layer of mineral oil. The cells readily attach, spread and migrate on the surface of a matrix-coated tissue culture dish as a confluent circular monolayer. Migration is measured as the net increase in the total area covered at 24 hours. We have used this system to quantify EC migration on matrices composed of a mixture of type I collagen and either von Willebrand factor (vWF) or fibronectin (FN) in the presence or absence of tumor necrosis factor (TNF). Plating efficiency on both vWF/collagen and FN/collagen, measured by counting cells after attachment and spreading, is about 80%. With this method, migration on vWF/collagen was about 6.4 mm2 and 5.3 mm2 for TNF-treated and untreated HUVEC, respectively. HUVEC migration on FN/collagen was slightly greater – 6.4 mm2 and 6.5 mm2 with and without TNF treatment, respectively. During the 24 hour time period, HUVEC numbers increased 30–40% on vWF/collagen, and 60–80% on FN/collagen, with increased proliferation observed with TNF- treatment. EC proliferation could be completely inhibited by 2 mM hydroxyurea. This assay system has proven useful in our studies to quantify cell migration and proliferation. 相似文献
87.
ASK1 associates with troponin T and induces troponin T phosphorylation and contractile dysfunction in cardiomyocytes 总被引:5,自引:0,他引:5 下载免费PDF全文
He X Liu Y Sharma V Dirksen RT Waugh R Sheu SS Min W 《The American journal of pathology》2003,163(1):243-251
There is increasing support for the idea that excessive production of proinflammatory mediators such as tumor necrosis factor (TNF) and reactive oxygen species (ROS) contribute to the pathogenesis of cardiac dysfunction. However, the mechanisms by which cytokine/ROS production mediates cardiac dysfunction have not been established. Given that apoptosis signal-regulating kinase 1 (ASK1) is highly expressed in cardiac muscle and that ASK1 is an important mediator in the signaling pathways induced by tumor necrosis factor, interleukin-1, and ROS, we used the yeast two-hybrid system with ASK1 as bait to identify ASK1 substrates from a human heart cDNA library. The cDNA encoding the cardiac troponin T (cTnT) was isolated. ASK1 specifically interacted with cTnT, but not cTnI, in vitro and in vivo via the C-terminal ASK1 domain. ASK1 specifically phosphorylated cTnT in vitro and in vivo. Mutations in cTnT (T194/S198) at an ASK1-phosphorylation consensus sequence significantly reduced phosphorylation by ASK1. ROS-induced ASK1 activation, cTnT phosphorylation, and contractile dysfunction in cardiomyocytes showed similar kinetics. Moreover, overexpression of constitutively active ASK1 induces cTnT phosphorylation and inhibits shortening and calcium transient in adult cardiomyocytes. We conclude that ASK1 plays an important role in regulation of cardiac contractile function by phosphorylating cTnT and may participate in cytokine/ROS-induced pathogenesis of cardiomyopathy and heart failure. 相似文献
88.
小鼠甲胎蛋白与结核杆菌热休克蛋白70基因融合载体的构建及体外表达 总被引:1,自引:0,他引:1
目的 构建小鼠甲胎蛋白(α-Fetoprotein,AFP)与结核杆菌热休克蛋白70(Mycobacterium tuberculosis heat shock protein 70,Mt.HSP70)基因融合载体.并研究其在真核细胞中的表达情况。方法 以pcDNA3.1为基本单位构建AFP及HSP70的融合表达载体,融合基因以G-S-G-G-S连接子连接;用脂质体将系列载体导入COS-7细胞.48h后以免疫化学方法检测其表达。结果 构建的AFP和HSP70的单独及融合表达载体导入COS-7细胞48h后经RT-PCR检测可扩增出相应片段,细胞免疫化学染色为阳性。结论 AFP和HSP70的单独及融合表达载体构建成功,并能在真核细胞中表达。 相似文献
89.
胃动素对血管灌流大鼠离体胃运动的作用 总被引:8,自引:1,他引:8
通过血管灌流大鼠离体胃,探讨胃动素对胃运动的影响。结果表明:(1)胃动素可以明显地兴奋胃窦自发的胃运动;(2)胃动素抗血清可以完全消除胃动素兴奋胃窦运动的作用;(3)阿托品可以阻断胃动素兴奋胃窦运动的作用。上述结果提示,胃动素可特异性兴奋血管灌流大鼠胃窦收缩运动,该作用通过壁内胆碱能神经介导。 相似文献
90.
Stanley K. Sessions Matthias Stöck David R. Vieites Ryan Quarles Mi-Sook Min David B. Wake 《Chromosome research》2008,16(4):563-574
A cytogenetic analysis, including the karyotype, C-bands, silver-stained nucleolus organizer regions and genome size, was performed on the recently discovered species, Karsenia koreana, the first plethodontid salamander from Asia. The karyotype consists of 14 pairs of bi-armed chromosomes, with no evidence of heteromorphic sex chromosomes. C-banding reveals a concentration of heterochromatin at the centromeres as well as at interstitial locations. The smallest chromosome (pair number 14) has symmetrical interstitial C-bands in each arm, resembling chromosome no. 14 of North American species of its sister group taxon, supergenus Hydromantes. Acomparative analysis of C-band heterochromatin and silver-stained nucleolus organizer regions of Karsenia and other plethodontid genera reveals that chromosomal evolution may have featured chromosome 'repatterning' within the context of conserved chromosome number and shape in this clade. Genome size is correlated with geographic distribution in plethodontids and appears to have important phenotypic correlates as well. The genome size of Karsenia is relatively large, and resembles that of the geographically closest plethodontids from western North America, especially species of the genus Hydromantes. The biological significance of these cytogenetic characteristics of plethodontid salamanders is discussed within an evolutionary context. 相似文献