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Placebo controls play a critical role in the evaluation of any pharmacotherapy. This review surveys the placebo arm in 12 randomized controlled trials (RCTs) investigating burning mouth syndrome (BMS) and documents a positive placebo response in 6 of them. On average, treatment with placebos produced a response that was 72% as large as the response to active drugs. The lack of homogeneity in the use of placebos adds to the difficulty in comparing results and aggregating data. Future RCTs investigating BMS would benefit from larger sample sizes, adequate follow‐up periods, and use of a standard placebo. 相似文献
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目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。
方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。
结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。
结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。 相似文献
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Kelly M. Morgan Jada G. Hamilton Heather Symecko Daniella Kamara Colby Jenkins Jenny Lester Kelsey Spielman Lydia E. Pace Camila Gabriel Jeffrey D. Levin Prince Rainier Tejada Anthony Braswell Vanessa Marcell Temima Wildman Bryan Devolder Robin Camhi Baum Jeremy N. Block Yuri Fesko Kenneth Offit 《Genetics in medicine》2022,24(3):564-575
PurposeThis study aimed to evaluate uptake and follow-up using internet-assisted population genetic testing (GT) for BRCA1/2 Ashkenazi Jewish founder pathogenic variants (AJPVs).MethodsAcross 4 cities in the United States, from December 2017 to March 2020, individuals aged ≥25 years with ≥1 Ashkenazi Jewish grandparent were offered enrollment. Participants consented and enrolled online with chatbot and video education, underwent BRCA1/2 AJPV GT, and chose to receive results from their primary care provider (PCP) or study staff. Surveys were conducted at baseline, at 12 weeks, and annually for 5 years.ResultsA total of 5193 participants enrolled and 4109 (79.1%) were tested (median age = 54, female = 77.1%). Upon enrollment, 35.1% of participants selected a PCP to disclose results, and 40.5% of PCPs agreed. Of those tested, 138 (3.4%) were AJPV heterozygotes of whom 21 (15.2%) had no significant family history of cancer, whereas 86 (62.3%) had a known familial pathogenic variant. At 12 weeks, 85.5% of participants with AJPVs planned increased cancer screening; only 3.7% with negative results and a significant family history reported further testing.ConclusionAlthough continued follow-up is needed, internet-enabled outreach can expand access to targeted GT using a medical model. Observed challenges for population genetic screening efforts include recruitment barriers, improving PCP engagement, and increasing uptake of additional testing when indicated. 相似文献
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Ketanserin prevents platelet aggregation and endotoxin-induced pulmonary vasoconstriction 总被引:1,自引:0,他引:1
T R Meuleman D C Hill J D Port T H Stanley N L Pace S F Mohammad 《Critical care medicine》1983,11(8):606-611
Pulmonary hypertension secondary to sepsis is due, in part, to release of serotonin from platelets. This study examines the effects of ketanserin, a new, highly specific serotonin antagonist, on platelet aggregation and the cardiovascular changes associated with bacterial endotoxemia in dogs. Ketanserin markedly inhibits in vitro platelet aggregation induced by mixing serotonin and epinephrine. When ketanserin is administered to animals before endotoxin infusion, cardiac output is greater and mean pulmonary artery pressure (MPAP), pulmonary and systemic vascular resistance (PVR and SVR) and arteriovenous oxygen content difference [C(a-v)O2] are less than in animals not receiving ketanserin. Similar results for PVR, SVR, and C(a-v)O2 are obtained when ketanserin is administered after endotoxin infusion. The data indicate that ketanserin inhibits serotonin-induced platelet aggregation and modifies many cardiovascular changes associated with bacterial endotoxemia. 相似文献
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C Defer ; J Coste ; F Descamps ; S Voisin ; JM Lemaire ; M Maniez ; AM Courouce 《Transfusion》1995,35(7):596-600
BACKGROUND: To verify the criteria for human T-lymphotropic virus (HTLV) seropositivity in Western blot (WB) proposed by the Retrovirus Study Group of the French Society of Blood Transfusion, 186 blood donations that were repeatedly reactive in HTLV enzyme-linked immunosorbent assay, selected according to their WB pattern, were tested by polymerase chain reaction (PCR) and radioimmunoprecipitation assay (RIPA). STUDY DESIGN AND METHODS: In two commercially available WBs, 12 samples were confirmed as positive (rgp21+p19+p24) and 174 were interpreted as indeterminate (one or two reactivities to these proteins). The primer pairs used for the PCR allowed the amplification of type I (HTLV-I) or type II (HTLV-II) (or both) sequences. The RIPA was performed with two 35S-labeled cell lines: HTLV-I infected HUT 102/B2 and HTLV-II-infected MoT. RESULTS: Of the 12 positive samples, 11 were classified as HTLV-I-positive and one as HTLV-II-positive. Among the 174 indeterminate samples, three (WB pattern: rgp21+, p19+, p24-) were HTLV-I positive in PCR (one of them was positive in RIPA also); the other 171 were HTLV negative. CONCLUSION: In the study of a population in which 97 percent of HTLV infections are due to HTLV-I, these data support the three-protein criteria (rgp21, p19, and p24) for a positive blot reading. No HTLV infection was observed when rgp21 did not react. Consequently, p19 and/or p24 band patterns represent false reactivity and do not require PCR or RIPA confirmation. To discriminate between false- and true-positive results in the absence of MTA-1 or K55 reactivity, PCR and/or RIPA is required only when rgp21 reactivity is associated with one gag band (p19 or p24). 相似文献
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JM Beis C Frenay JM André AM Datié A Baumgarten 《Annales de Réadaptation et de Médecine Physique》1996,39(8):527-533
The use of eye-patches allows to modulate the visual information treating process. Twelve subjects with a left unilateral spatial neglect, randomly divided into three groups — non treated, treated by right eye complete patching, treated by right hemifield patching — were assessed at 1 month and 3 months after acute episode, by means of functional and neuropsychological tests. Results in the subjects treated by complete eye-patch [5]show an improvement of all the assessment parameters whatever the unilateral spatial neglect seriousness degree may be. The progression is less convincing in the patients treated by eye-patch in right hemifield. The effects of the different modalities of occultation interpreted on the basis of anatomo-physiological and psychophysiological patterns of attention, suggest the role of ocular occultation in the initial, voluntary and directed, coven attention recovery and secondary of the automatic and divided overt attention. 相似文献