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51.
Several problems in the management of life-threatening mucormycosis remain unresolved, necessitating new methods of management. Four patients with histopathologically proven rhinocerebral mucormycosis were treated with high cumulative doses of granulocyte colony-stimulating factor (G-CSF). All had multiple predisposing factors for mucormycosis, particularly leukemia and neutropenia. Two patients refractory to fluconazole therapy were treated with liposomal amphotericin B. The improvement in clinical manifestations was closely related to neutrophil recovery, and all patients were alive at the end of therapy. In addition to surgical debridement and antifungal therapy, G-CSF seems to have played a role in their survival.  相似文献   
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Clonal chromosome abnormalities were found in short-term cultures from two epithelial skin tumors, a basal cell papilloma and a keratoacanthoma. The three-way translocation t(2;6;11)(q21;q27;p13) was the sole clonal rearrangement in the basal cell papilloma. The karyotype of the keratoacanthoma was more complex: 46,XX,der(2)(2pter----2p13::2p11----cen----2q37: :5q33----5qter),der(2) (:2p13----cen----2q37::6q23----6qter),der(5)t(2; 7;5)(q37;q11;q33),der(6) (6pter----cen----6q23::2p13----2pter),der(7)t(2; 7;5)(q37;q11;q33), del(13)(q11q14). In addition, several nonclonal structural changes were seen in both tumors.  相似文献   
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55.
Yin  Xuewei  Liu  Bin  Wei  Huixia  Wu  Shanshan  Guo  Lijie  Xu  Furu  Liu  TingTing  Bi  Hongsheng  Guo  Dadong 《Inflammation research》2019,68(9):761-774
Objective and design

The present study aimed to investigate the relationship between the disturbed balance of CD4+/CD8+, Th17/Treg and the activation of the Notch signaling pathway in experimental autoimmune uveitis (EAU).

Methods

An EAU rat model was induced in Lewis rats, and pathology analysis was performed by hematoxylin and eosin (H&E) staining. CD4+, CD8+, Th17, and Treg levels in spleen, lymph nodes and eye tissues were determined by flow cytometry. Meanwhile, the expression of Notch1, DLL4, IL-10, and IL-17 was determined by quantitative polymerase chain reaction (Q-PCR) and enzyme-linked immunosorbent assay (ELISA). In addition, the inhibitory effect of N-(N-(3,5-difluorophenacetyl-l-alanyl))-S-phenylglycine t-butyl ester (DAPT) on Th17 differentiation by Notch signaling in vitro was further investigated using T lymphocytes from EAU rats on day 12 post-immunization by flow cytometry.

Results

The pathological results showed that inflammatory cell infiltration occurred in ocular tissues in EAU rats. The CD4+/CD8+ and Th17/Treg ratios in EAU rats were apparently higher than those in normal control individuals. Q-PCR and ELISA analyses indicated the expression of Notch1, DLL4, IL-10, and IL-17 in EAU rats gradually increased on day 6 after immunization, peaked on day 12, and then gradually decreased. The dynamic trends in Notch1 and DLL4 expression in EAU rats were identical to those of CD4+/CD8+ and Th17/Treg levels. DAPT can significantly inhibit the activation of Notch signaling, decrease Th17 cell differentiation, and attenuate the level of the Th17 cell lineage, contributing to the balance of the Th17/Treg ratio.

Conclusion

The activation of the Notch signaling pathway can regulate Th17 and Treg cell differentiation, disrupt the CD4+/CD8+ and Th17/Treg balance, and aggravate the severity of EAU; inactivation of the Notch signaling pathway contributes to the CD4+/CD8+ and Th17/Treg balance in EAU rats. Our findings highlighted that the dynamic change in the CD4+/CD8+ and Th17/Treg ratio was consistent with the expression trend of Notch signaling in EAU rats, suggesting that Notch signaling may be a potentially important therapeutic target in clinical practice.

  相似文献   
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An approximately 4-Mb genomic segment on chromosome 17p11.2, commonly deleted in patients with the Smith-Magenis syndrome (SMS) and duplicated in patients with dup(17)(p11.2p11.2) syndrome, is flanked by large, complex low-copy repeats (LCRs), termed proximal and distal SMS-REP. A third copy, the middle SMS-REP, is located between them. SMS-REPs are believed to mediate nonallelic homologous recombination, resulting in both SMS deletions and reciprocal duplications. To delineate the genomic structure and evolutionary origin of SMS-REPs, we constructed a bacterial artificial chromosome/P1 artificial chromosome contig spanning the entire SMS region, including the SMS-REPs, determined its genomic sequence, and used fluorescence in situ hybridization to study the evolution of SMS-REP in several primate species. Our analysis shows that both the proximal SMS-REP (approximately 256 kb) and the distal copy (approximately 176 kb) are located in the same orientation and derived from a progenitor copy, whereas the middle SMS-REP (approximately 241 kb) is inverted and appears to have been derived from the proximal copy. The SMS-REP LCRs are highly homologous (>98%) and contain at least 14 genes/pseudogenes each. SMS-REPs are not present in mice and were duplicated after the divergence of New World monkeys from pre-monkeys approximately 40-65 million years ago. Our findings potentially explain why the vast majority of SMS deletions and dup(17)(p11.2p11.2) occur at proximal and distal SMS-REPs and further support previous observations that higher-order genomic architecture involving LCRs arose recently during primate speciation and may predispose the human genome to both meiotic and mitotic rearrangements.  相似文献   
58.
中草药的变态反应   总被引:6,自引:0,他引:6  
通过大量的文献调查、以鱼腥草和丹参及其制剂引起的变态反应为重点,介绍常用中草药诱发变态反应的临床表现、分型、处理和预防方法。为临床安全、有效使用中草药提供借鉴。  相似文献   
59.
丙型肝炎病毒母婴传播研究   总被引:2,自引:0,他引:2  
目的:探讨HCV母婴传播的可能性及其在流行病学中的意义。方法:应用ELISA方法对2136名产前检查的孕妇进行了抗-HCV检测,抗-HCV阳性者进一步应用PCR检测其HCV-RNA并收集其婴儿脐血进行抗-HCV和HCV-RNA检测。结果:孕妇的抗-HCV阳性率为1.59%(34/2136),抗-HCV阳性母亲的HCV-RNA阳性率为47.06%(16/34),母亲HCV-RNA阳性者发生垂直传播率为53.3%。结论 :应用抗-HCV评价母婴传播并不合和达,只有通过检测HCV-RNA方能证实感染的存在。HCV确实存在母婴传播,但在人群HCV流行中并非主要传播途径。母新肝功能异常是影响HCV母婴传播的一个重要因素。  相似文献   
60.
川芎素对冠心病血浆脂质过氧化物及血流动力学影响   总被引:5,自引:0,他引:5  
目的:观察川芎素对冠心病患者血浆脂质过氧化物及血流动力学影响。方法:60例冠心病患者随机分为川芎素组和对照组,每组30例,观察用药前后血浆脂质过氧化物(LPO),超氧化物歧化酶(SOD)及血液动力学的变化。结果:川芎素治疗组患者血LPO下降(P<0.01),SOD升高(P<0.05),血流动力学各项指标均好转,结论:川芎素能降低脂质过氧化,降低血粘滞度,提示川芎素对心病有一定的治疗作用。  相似文献   
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