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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
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Garner EI Goldstein DP Feltmate CM Berkowitz RS 《Clinical obstetrics and gynecology》2007,50(1):112-122
Hydatidiform mole, a disorder of fertilization, comprises complete and partial molar pregnancy. The pathologic and clinical features of complete and partial mole are well-described. Because of earlier diagnosis, however, the clinical presentation of complete molar pregnancy has significantly changed in recent years. The earlier diagnosis of complete mole is associated with more subtle pathologic findings than later molar pregnancy. The use of immunohistochemical techniques for the detection of maternally imprinted genes as ancillary testing in the diagnosis of complete and partial mole is therefore increasing. Although most molar pregnancies are sporadic, a familial syndrome of recurrent hydatidiform mole has been described. Further research will hopefully lead to identification of the gene defect responsible for this uncommon syndrome. Fortunately, patients with molar pregnancies can generally anticipate normal future reproduction. Close hCG follow-up after molar pregnancy is required to rule out development of postmolar gestational trophoblastic neoplasia. Recent studies suggest that a shorter period of postmolar follow-up may be reasonable for patients with both complete and partial molar pregnancy. 相似文献
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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
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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
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David C. Houghton Colleen S. McFarland Martin E. Franklin Michael P. Twohig Scott N. Compton Angela M. Neal-Barnett 《Psychiatry》2016,79(2):164-169
Objective: Trichotillomania (TTM) is associated with significant embarrassment and is viewed negatively by others. A potentially important outcome variable that is often overlooked in treatment for TTM is appearance and social perception. Method: The present study tested whether participants in a randomized controlled trial (RCT) of psychotherapy for TTM are viewed more positively by others. All participants in the trial were photographed at baseline and posttreatment. Three treatment responders and three treatment nonresponders were selected randomly for the present study. Several healthy controls were also photographed in a similar manner. Undergraduate college students (N = 245) assessed whether they would reject the person socially, whether the individual has a psychological or medical problem, and attractiveness. Results: Individuals with TTM were viewed more negatively than healthy controls at baseline, but treatment responders showed positive improvements on all perceptions relative to nonresponders. While treatment responders were still perceived more poorly than controls on social rejection and perceptions of problems at posttreatment, responders where rated no differently than controls on attractiveness at posttreatment. Conclusions: The results suggest that persons with TTM who respond to treatment are rated by others as significantly improved in appearance, but they might be still stigmatized or socially rejected. 相似文献
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Hanin Rashid Robert Lebeau Norma Saks Anthony R. Artino Judy A. Shea 《Teaching and learning in medicine》2016,28(4):353-357
This Conversation Starters article presents a selected research abstract from the 2016 Association of American Medical Colleges Northeast Region Group on Educational Affairs annual spring meeting. The abstract is paired with the integrative commentary of three experts who shared their thoughts stimulated by the pilot study. These thoughts explore the metacognitive, social, and environmental mechanisms whereby advice plays a role in self-regulated learning. 相似文献