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41.
M Solé J Cano J L Rodríguez-Tudela J Pontón D A Sutton R Perrie J Gené V Rodríguez J Guarro 《Medical mycology》2003,41(4):293-300
Invasive infections by Scedosporium prolificans have increased alarmingly in recent years, mainly in immunosuppressed patients. The epidemiology, pathogenesis and the natural habitat of this pathogen are practically unknown. Isolates of S. prolificans were distinguished from one another by inter-simple-sequence-repeat (ISSR) fingerprinting, a technique based on the high degree of polymorphism of the multisatellite genetic markers used. This technique was found useful for typing 84 isolates of S. prolificans from different countries and sources. The assemblage of S. prolificans isolates tested was extremely diverse, with 35 genotypes present. Several patients were found to have been infected or colonized by more than one strain. Overall, this technique facilitates the epidemiological study of S. prolificans infection. 相似文献
42.
Enkephalin-like immunoreactive (ENK-IR) neurons and fibers in the rat ventromedial hypothalamic nucleus (VMH) were examined by light and electron microscopy using the peroxidase-antiperoxidase immunocytochemistry. There were groups of ENK-IR neurons present in the ventrolateral part of the VMH, and such neurons were scattered elsewhere. These neurons had perikarya 10-25 microns in diameter with moderately developed cell organelles and enfolded nuclei that were often distributed eccentrically placed in the cell. The perikarya and dendrites contained diffuse, large-cored vesicles (LCV) (60-230 nm with a predominance in the 60-80 nm). ENK-IR neurons received synaptic inputs on the soma and dendrites from unlabeled axonal boutons containing many small, clear vesicles and occasional LCV. The ultrastructural features of the ENK-IR cells in the VMH seemed to correspond to the "common cells" described by Millhouse. Dense ENK-IR fibers were distributed in this nucleus throughout the rostrocaudal and ventrodorsal areas. Axonal boutons containing numerous small, clear vesicles, and dispersed LCV generally made synaptic contacts with the cell bodies and dendrites of unlabeled neurons. The findings suggest that opioid peptides directly influence VMH neurons through synaptic contacts. 相似文献
43.
研究了明胶水凝胶在绝缘硅油中的电场响应行为。结果表明,在硅油中,明胶水凝胶在外加高压直流电场作用下可发生运动,其运动由转动和平动两部分组成。存在一个运动所需的最小阈值电场,只有外加电场在此阈值以上时,才可观察到水凝胶明显的运动。水凝胶的运动速度随外加电场的增大而增大,其运动可通过外加电场的大小来调控。由硅油很稳定且在电场中会电解,因此避免了传统电场驱动水凝胶在水介质中响应时不可避免的电解缺点,为建立一种新的电响应凝毅然驱动方式提供了可能。 相似文献
44.
A surveillance study of patterns of reirradiation practice using external beam radiotherapy in Japan
Hideya Yamazaki Gen Suzuki Norihiro Aibe Satoaki Nakamura Ken Yoshida Ryoongjin Oh JReRT Group 《Journal of radiation research》2021,62(2):285
The aim of this study was to survey the present status and patterns of reirradiation (Re-RT) practice using external beam radiotherapy in Japan. We distributed an e-mail questionnaire to the Japanese Society for Radiation Oncology partner institutions, which consisted of part 1 (number of Re-RT cases in 2008–2012 and 2013–2018) and part 2 (indications and treatment planning for Re-RT and eight case scenarios). Of the 85 institutions that replied to part 1, 75 (88%) performed Re-RTs. However, 59 of these 75 institutions (79%) reported difficulty in obtaining Re-RT case information from their databases. The responses from 37 institutions included the number of Re-RT cases, which totaled 508 in the period from 2009 to 2013 (institution median 3; 0–235), and an increase to 762 cases in the period from 2014 to 2018 (12.5; 0–295). A total of 47 physicians responded to part 2 of the survey. Important indications for Re-RT that were considered were age, performance status, life expectancy, absence of distant metastases and time interval since previous radiotherapy. In addition to clinical decision-making factors, previous total radiation dose, volume of irradiated tissue and the biologically equivalent dose were considered during Re-RT planning. From the eight site-specific scenarios presented to the respondents, >60% of radiation oncologists agreed to perform Re-RT. Re-RT cases have increased in number, and interest in Re-RT among radiation oncologists has increased recently due to advances in technology. However, several problems exist that emphasize the need for consensus building and the establishment of guidelines for practice and prospective evaluation. 相似文献
45.
46.
I型内皮素受体反义寡聚核苷酸抑制VSMC增殖及内膜增生 总被引:4,自引:1,他引:3
目的 观察 型内皮素受体 (ETA)反义寡核苷酸(ODN)对血管平滑肌细胞 (VSMC)增殖和内膜增生的抑制作用 .方法 1细胞培养 :取家兔主动脉中膜消化后培养传代 ,经抗 α- actin鉴定后使用第 4~ 6代传代细胞 ;2人工合成ODN:经 Genbank检索筛选 ,合成含 18bp ETA- ODN片段 ,再对 5 端硫代修饰以增加稳定性 ,同时行地高辛标记以检测反义片段的细胞膜穿透性 ;3 MTT分光光度法检测 ETA-ODN对 VSMC增殖的抑制作用 ;4运用放射受体结合分析法 (1 2 5I- ET- 1)了解 ODN对 ETA蛋白表达的抑制作用 ,以探讨其反义作用 ;5兔颈动脉空气干燥模型在体研究 ODN对血管内膜增生的抑制作用 :应用 F- 12 7凝胶载体携带 ETA-ODN(3.0μmol· L- 1 )导入血管周围 ,术后不同时间观察增生内膜相对厚度 .结果 ODN于培养后 12 h进入细胞内 ,并逐渐增加 ;15 μmol· L- 1 ETA- ODN对 VSMC增殖具有抑制作用 ,2 4h后即有显著作用 ;ETA- ODN对 ETA表达亦有明显的抑制作用 ,表现为 CPM于 2 4h逐渐减少 ;ETA- ODN导入后 ,血管增生内膜相对厚度减少 .结论 ETA- ODN以浓度和时间依赖方式抑制 ETA蛋白表达以及 VSMC的增殖 ;反义寡核苷酸是通过反义机制实现对 ETA蛋白和 VSMC增殖的抑制作用 相似文献
47.
目的:探讨肿瘤微血管与前列腺癌生长,转移的关系。方法:应用免疫组化技术结合放射免疫测定检测第Ⅷ因子相关抗原和前列腺特异性抗原(PSA)在19例前列腺癌和40例前列腺增生中的表达和平均值及其相关关系。结果:前列腺癌组织中微血管密度(MVD)和PSA值明显高于前列腺增生,转移性前列腺癌MVD和PSA值高于非转移性前列腺癌,前列腺癌MVD与PSA呈正相关,结论:血管形成与前列腺癌的发生,发展和转移密切相关,肿瘤的增长和转移有赖于肿瘤血管的生成。 相似文献
48.
职业性慢性放射病临床诊断及预后 总被引:1,自引:0,他引:1
目的:探讨慢性放射病(以下简称慢放病)的诊断、治疗及预后。方法:以受照剂量,临床症状,造血功能,T淋巴细胞百分率,染色体畸变率对30例慢性放射损伤患者进行综合分析判断,对其中11例慢放病用胸腺肽治疗并追踪观察10年。结果:慢放病患者受照剂量超过2Sv,白细胞下降伴有几髓造血功能障碍,T淋巴细胞百分率下降,染色体畸变率显著上升。胸腺肽能改善临床症状,显著提高细胞免疫功能。慢放病各项指标恢复依时间顺序为:T淋巴细胞百分率(2年),临床症状(3.5年),造血功能(5~8年),染色体畸变率(10年)。结论:受照剂量是误断慢放病的重要依据;白细胞总数、骨髓造血功能改变是诊断的关键;T淋巴细胞百分率、染色体畸变率可作为鉴别诊断指标。慢放病是一种可以恢复的职业性疾病,胸腺肽治疗有助于慢放病的恢复。 相似文献
49.
Great horovement haS been made in the cryopreservation Of inalnlnalian elnbmp since wnttingham['] reported his Pioneering wold about successful cryOPreservationof mouse embryo. It results in the availability of cryOPreserVation of embryos of all stages[']. HOwever, cryopreserved embryos can not avoid the damages by ice crystal,which is a major cause of cen death in the freezing andthawing ProceduresL',']. SO it is necesseq to seareh for anew and more efficient method for embryO cryOPrese… 相似文献
50.