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51.
Collagen autoimmunity has been suggested as one etiologic mechanism to otosclerosis. Although substantial studies relating this disease to collagen autoimmunity have been reported, a basic understanding of the pathogenic mechanism involved is lacking. Some otosclerosis patients have a high level of antibody to type II collagen. In addition, complement and antibody were deposited in the stapes from otosclerosis patients. Furthermore, the otic capsule and stapes have been found to contain type II collagen by immunohistologic studies and biochemical analysis. Otospongiosis-like lesions have also been produced in rats by immunizing them with type II collagen. This finding led us to postulate a hypothesis of an autoimmunity to type II collagen as an etiopathogenesis of this illness. Our initial hypothesis has been updated to incorporate new findings in the field of cell biology. The role of interleukin 1, osteoclasts, osteoblasts, bone resorption, and other factors such as minor collagens, calcitonin, vitamin D, parathyroid hormone, collagenase, and prostaglandins are incorporated in this updated hypothesis. 相似文献
52.
Engineering the follicle microenvironment 总被引:1,自引:0,他引:1
In vitro ovarian follicle culture provides a tool to investigate folliculogenesis, and may one day provide women with fertility-preservation options. The application of tissue engineering principles to ovarian follicle maturation may enable the creation of controllable microenvironments that will coordinate the growth of the multiple cellular compartments within the follicle. Three-dimensional culture systems can preserve follicle architecture, thereby maintaining critical cell-cell and cell-matrix signaling lost in traditional two-dimensional attached follicle culture systems. Maintaining the follicular structure while manipulating the biochemical and mechanical environment will enable the development of controllable systems to investigate the fundamental biological principles underlying follicle maturation. This review describes recent advances in ovarian follicle culture, and highlights the tissue engineering principles that may be applied to follicle culture, with the ultimate objective of germline preservation for females facing premature infertility. 相似文献
53.
文章从创新及创新型人才的概念入手,通过调研指出,目前临床医学人才培养存在的主要问题,提出在新时期要转变教育教学观念、强化创新意识教育、增强创新思维训练、着力创新人格塑造,以培养创新型临床医学人才。 相似文献
54.
目的:探讨化合物YD383和YD439对STAT6信号传导通路的作用是否具有特异性.方法:通过瞬时转染的方法将分别依赖于STAT1和STAT6活性的带有荧光素酶报告基因的质粒转染至HeLa细胞株,两种细胞株在各自相应的细胞因子(IFN-γ或IL-4)刺激下激活JAK-STAT1或JAK-STAT6信号传导通路.通过测定荧光素酶的活性来评价细胞株在化合物存在的情况下报告基因的表达.结果:YD383和YD439均能降低相应细胞因子刺激引起的报告基因的表达,并且具有剂量依赖性.随着化合物剂量的增加,报告基因的表达降低(P<0.05).但化合物引起的两种转染细胞报告基因表达降低的差异比较无统计学意义(P>0.05).结论:两种化合物对JAK-STAT1和JAK-STAT6信号传导通路均有抑制作用,对JAK-STAT6通路的抑制不具有特异性. 相似文献
55.
Lisa Shea Jacqueline Pesa Gabrielle Geonnotti Valerie Powell Caryl Kahn Wesley Peters 《Health expectations》2022,25(4):1979
IntroductionThe lack of racial/ethnic diversity in research potentially limits the generalizability of findings to a broader population, highlighting the need for greater diversity and inclusion in clinical research. Qualitative research (i.e., focus groups) was conducted to identify (i) the potential motivators and barriers to study participation across different races and ethnicities; (ii) preferred delivery of education and information to support healthcare decision‐making and the role of the community.MethodsPatient focus groups were conducted with 26 participants from the sponsor''s Patient Engagement Research Councils selected through subjective sampling. Recruitment prioritized adequate representation across different race/ethnic groups. Participation was voluntary and participants underwent a confidential interview process before selection. Narrative analysis was used to identify themes and draw insights from interactions. Experienced research specialists identified emerging concepts, and these were tested against new observations. The frequency of each concept was examined to understand its importance.ResultsBased on self‐selected race/ethnicity, participants were divided into five focus groups (Groups: African American/Black: 2; Hispanic/Latino, Asian American, and white: 1 each) and were asked to share their experiences/opinions regarding the stated objectives. Barriers to study participation included: limited awareness of opportunities to participate in research, fears about changes in standard therapy, breaking cultural norms/stigma, religion‐related concerns and mistrust of clinical research. Participants identified the importance of transparency by pharmaceutical companies and other entities to build trust and partnership and cited key roles that communities can play. The perceptions of the African American group regarding diversity/inclusion in research studies appeared to be different from other groups; a lack of trust in healthcare providers, concerns about historical instances of research abuse and the importance of prayer were cited.ConclusionThis study provided insights into barriers to study participation, and also highlighted the need for pharmaceutical companies and other entities to authentically engage in strategies that build trust within communities to enhance recruitment among diverse populations.Patient or Public ContributionThe data collected in the present study was provided by the participants in the focus groups. 相似文献
56.
1958例系统性红斑狼疮住院患者临床特征分析 总被引:1,自引:0,他引:1
目的回顾性分析系统性红斑狼疮(SLE)住院患者的临床特征,分析其发病形式及患者就诊时的情况。方法采用流行病学调查的方法,随机抽取江苏省10年来1 958例SLE住院患者的病历,分析其临床特征,采用SPSS 13.0软件包进行统计学分析。结果①在1 958份病例中,临床特征以关节痛(炎)最多(53.8%),其次为面部红斑(48.3%)、发热(36.1%)、肾损害症状(24.5%)。②男女发病比例为1.0︰15.0,男性以皮疹最多见,占59.0%,高于女性47.6%,其次为发热(47.5%),高于女性(35.3%),关节痛(炎)(45.9%低于女性(54.3%),男性肾损害(36.9%),高于女性(23.7%)。③不同年龄患病率:≤20岁(19.2%),>40岁(18.8%),20~40岁(62.0%)。④从出现症状到住院:发热13.8个月,肾损害症状19.5个月,关节痛(炎)36.9个月,面部红斑37.2个月。结论关节痛(炎)、面部红斑、发热是SLE最常见的临床表现,是就诊的主因。中青年女性发病率高,男性皮疹、发热、肾损害发生率高,而女性关节痛(炎)发生率高于男性。 相似文献
57.
目的初步探寻人外周血自然杀伤细胞(Nature Killer,NK)杀伤细胞免疫球蛋白样受体(Killer Cell Immnoglobulin-Like Receptor,KIR3DL1)表达可能存在的microRNA(miR)调控机制。方法利用生物信息学方法,从miR信息库中筛选出可能与KIR3DL1相关的miRs,构建含KIR3DL1 3’非翻译区(UTR)的PGL3质粒,分别将含相应miR的PcDNA3.0质粒与前者共转染293T细胞,通过荧光素酶报告实验及之后的突变实验筛选出可能调控KIR3DL1的miR。结果通过TARGET SCAN信息库筛选了miR-146b等10个miR;转染miR-146b后,荧光素酶活性下降最多(61.3%),突变其KIR3DL1 3’UTR靶位点后荧光素酶活性恢复(91.4%)。结论 miR-146b可与KIR3DL1’UTR在靶位点特异结合,很可能参与KIR3DL1表达的调控。 相似文献
58.
目的 制备兔抗人血小板膜糖蛋白(GP)Ibα C端557~561氨基酸序列多肽的多克隆抗体,并初步用于人血小板GPIbα C端559位丝氨酸磷酸化状态的检测.方法 应用化学方法合成C-R-G-S-L-P(559位丝氨酸非磷酸化,Ser559)和C-R-G-s(p)-L-P(559位丝氨酸磷酸化,pSer559)多肽.将2种多肽分别与钥孔蜮血蓝蛋白交联后,以皮下注射法分别免疫新西兰大白兔,分离获得2种抗血清(抗Ser559多抗和抗pSer559多抗).应用斑点印迹和酶联免疫吸附试验(ELISA)方法 对抗血清进行鉴定并检测效价.从人血小板裂解液中分离纯化血小板GPIbα,利用抗Ser559多抗和抗pSer559多抗、采用ELISA方法检测人血小板GPIbαC端559位丝氨酸磷酸化状况.结果 所制备的2种多抗分别特异性识别各自抗原,效价分别为1:32 000和1:64 000.2种多抗均可与纯化的人血小板GPIbα特异结合,表明人血小板GPIbα 559位点丝氨酸存在磷酸化与非磷酸化两种状态.结论 应用人工合成多肽成功制备出2种可特异性识别丝氨酸磷酸化状态的兔抗人血小板GPIbα胞内段多肽多抗,并证明人血小板GPIbαC端559位丝氨酸存在磷酸化状态. 相似文献
59.
Folate deficiency contributes to a variety of age-related neurological and psychological disorders including amyotrophic lateral sclerosis (ALS). The environmental neurotoxin arsenic has recently been linked with decreased neurofilament (NF) content in peripheral nerve. We examined herein, whether or not folate deprivation potentiated the impact of arsenic on NF dynamics. Arsenic inhibited translocation of NFs into axonal neurites in culture and increased perikaryal NF phosphoepitopes. Folate deprivation potentiated the impact of arsenic on these phenomena. Supplementation with S-adenosyl methionine (SAM) attenuated the impact of folate deprivation on arsenic neurotoxicity, consistent with the decrease in SAM following folate deprivation and the requirement for SAM-mediated methylation for arsenic bioelimination. These findings demonstrate how key nutritional deficiencies can potentiate the impact of enrivonmental neurotoxins. 相似文献