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101.
Stepanovic S Dakic I Morrison D Hauschild T Jezek P Petrás P Martel A Vukovic D Shittu A Devriese LA 《Journal of clinical microbiology》2005,43(2):956-958
A total of 28 staphylococcal isolates from human clinical specimens belonging to the Staphylococcus sciuri group were identified and characterized. The API Staph and ID32 STAPH correctly identified S. sciuri and S. lentus but not S. vitulinus strains. Identification to the subspecies level was possible only by a PCR-based method. 相似文献
102.
原发性中枢神经系统恶性淋巴瘤MR表现及其病理学基础 总被引:5,自引:0,他引:5
目的 研究原发性中枢神经系统恶性淋巴瘤(PCNSL)的MR表现及其病理学基础。方法 分析13例手术病理证实的原发性中枢神经系统恶性淋巴瘤的临床病理及MR表现。结果 13例中单发肿瘤4例,多发肿瘤9例,共计36个病灶。13例病变均累及幕上,其中8例病灶位于深部脑白质近脑室旁。肿瘤平均最大径为3.2cm。T1WI略低信号28个,T2WI等信号24个。28个病灶呈均匀强化。肿瘤水肿及占位效应相对较轻。2例PCNSL行MR动态增强扫描,早期强化均不明显,时间-信号强度曲线呈缓慢上升型。病理上肿瘤细胞弥漫分布,瘤细胞大小较一致,细胞质少,细胞核大,染色质颗粒粗,可见瘤细胞围绕血管呈袖套样浸润,少见明显的出血及片状坏死,未见钙化,病理均为非霍奇金淋巴瘤。结论 原发性中枢神经系统恶性淋巴瘤的病理基础决定其MR增强形态、占位程度以及肿瘤发生部位具有一定特征,运用不同的MR影像学检查方法和技术,在多数情况下可以做出术前正确诊断。 相似文献
103.
Megan E. Rech John M. McCarthy Chun‐An Chen Jane C. Edmond Veeral S. Shah Daniëlle G. M. Bosch Gerard T. Berry Linford Williams Suneeta Madan‐Khetarpal Dmitriy Niyazov Charles Shaw‐Smith Erin M. Kovar Philip J. Lupo Christian P. Schaaf 《American journal of medical genetics. Part A》2020,182(6):1426-1437
Bosch–Boonstra–Schaaf Optic Atrophy Syndrome (BBSOAS) is an autosomal dominant neurodevelopmental disorder caused by loss‐of‐function variants in NR2F1 and characterized by visual impairment, developmental delay, and intellectual disability. Here we report 18 new cases, provide additional clinical information for 9 previously reported individuals, and review an additional 27 published cases to present a total of 54 patients. Among these are 22 individuals with point mutations or in‐frame deletions in the DNA‐binding domain (DBD), and 32 individuals with other types of variants including whole‐gene deletions, nonsense and frameshift variants, and point mutations outside the DBD. We corroborate previously described clinical characteristics including developmental delay, intellectual disability, autism spectrum disorder diagnoses/features thereof, cognitive/behavioral anomalies, hypotonia, feeding difficulties, abnormal brain MRI findings, and seizures. We also confirm a vision phenotype that includes optic nerve hypoplasia, optic atrophy, and cortical visual impairment. Additionally, we expand the vision phenotype to include alacrima and manifest latent nystagmus (fusional maldevelopment), and we broaden the behavioral phenotypic spectrum to include a love of music, an unusually good long‐term memory, sleep difficulties, a high pain tolerance, and touch sensitivity. Furthermore, we provide additional evidence for genotype–phenotype correlations, specifically supporting a more severe phenotype associated with DBD variants. 相似文献
104.
目的:报道1例偶然发现的右侧永久性三叉动脉形态、特点,并进行文献复习。方法:利用显微解剖对此例永久性三叉动脉的起源、走行、分支、分布、与后循环连接关系、以及相关动脉解剖特点等进行了研究。结果:此例永久性三叉动脉与脑膜垂体干共干起源于颈内动脉海绵窦段,于展神经外侧进入后颅窝,分支与基底动脉和小脑上动脉吻合,其终末支之一延续为同侧的小脑下后动脉,此动脉与三叉神经关系密切,分支分布于脑干和小脑。结论:永久性三叉动脉与后循环关系复杂,广泛参与正常脑组织供血。 相似文献
105.
106.
脊神经后支形态特点及其阻滞麻醉下腰椎间盘手术4063例报告 总被引:2,自引:1,他引:2
目的 :介绍一种安全、简便、有效的腰椎间盘手术的局麻方法—脊神经后支阻滞法。方法 :0 .5 %普鲁卡因 10 0ml和 2 %利多卡因 2 0ml混合备用。先在切口处皮内注射 5ml麻药 ,再于开窗侧阻滞 5根脊神经后支主干 (上 3下 2 ) ,麻药用量 3~ 5ml。脊神经后支主干位于横突根部上缘。其体表投影点的确定方法是通过上下棘突连线的上中 1 3交界点作一水平线 ,该线是横突的上缘线的体表投影 ;旁开腰 1棘突 2cm取一点 ;再旁开腰 5棘突 3cm取一点 ;通过这两点作一直线 ,该线与各横线的交点即为各脊神经后支主干部的发出点。结果 :40 63例麻醉效果 :优 72 .2 % ,良 2 4.6% ,中 3 % ,差 0 .2 %。效果差者 ,经静脉使用镇痛镇静类药也取得较好效果。结论 :腰椎间盘手术采用脊神经后支阻滞麻醉经济安全可靠。 相似文献
107.
Involvement of ERK, p38 and NF-kappaB signal transduction in regulation of TLR2, TLR4 and TLR9 gene expression induced by lipopolysaccharide in mouse dendritic cells 总被引:7,自引:0,他引:7 下载免费PDF全文
An H Yu Y Zhang M Xu H Qi R Yan X Liu S Wang W Guo Z Guo J Qin Z Cao X 《Immunology》2002,106(1):38-45
Toll-like receptors (TLR) are sentinel receptors capable of recognizing pathogen-associated molecule patterns (PAMP) such as lipopolysaccharide (LPS) and CpG-containing oligonucleotides (CpG ODN). TLR2 and TLR4 are major receptors for Gram-positive and Gram-negative bacterial cell wall components, respectively. TLR9 is necessary for CpG signalling. LPS or CpG ODN can activate immature dendritic cells (DC) and induce DC maturation characterized by production of cytokines, up-regulation of co-stimulatory molecules, and increased ability to activate T cells. However, little is known regarding the regulation of TLR gene expression in mouse DC. In this study, we investigated the regulation of TLR2, TLR4 and TLR9 gene expression by LPS in murine immature DC. TLR2, TLR4 and TLR9 mRNA were up-regulated following LPS stimulation. The up-regulation of TLR9 expression coincided with significantly increased production of tumour necrosis factor-alpha induced by LPS plus CpG ODN. While inhibition of extracellular signal-related kinase and NF-kappaB activation suppressed the up-regulation of the expression of TLR2, TLR4 and TLR9 mRNA, inhibition of p38 kinase prevented the up-regulation of TLR2 and TLR4 mRNA expression but enhanced the up-regulation of TLR9 expression. These results demonstrated that TLR2, TLR4 and TLR9 gene expression was differently regulated by LPS in mouse immature DC. Up-regulation of TLR2, TLR4 and TLR9 expression by LPS might promote the overall responses of DC to bacteria and help to explain the synergy between LPS and other bacterial products in the induction of cytokine production. 相似文献
108.
研究单次及长期维持血液透析时尿毒症患者血液流变性改变的影响。结果表明,单次血透后,红细胞比积明显升高,红细胞刚性明显降低;血浆粘度、红细胞聚集指数、Casson粘度、血液屈服应力及低切至高切的全血粘度无明显改变。维持血透患者的红细胞比积、血浆粘度、红细胞聚集指数、Casson粘度、血液屈服应力均无明显改变。进一步研究发现,单次血透后血浆渗透比明显降低.这可能是引起红细胞比积升高、红细胞刚性降低的原因之一。 相似文献
109.
Xanthii Fructus (XF) is an herb widely used in medicine for the treatment of a variety of inflammatory pathologies. In this study, using mouse peritoneal macrophages, we have examined whether XF affects nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-12p40 production induced by interferon (IFN)-γ and lipopolysaccharide (LPS). XF inhibits IFN-γ and LPS-induced NO production in a dose dependent manner. The decrease in NO synthesis was reflected as a decreased amount of inducible NO synthase protein. Furthermore, we also found that XF inhibits pro-inflammatory cytokine TNF-α production. However, treatment of XF in peritoneal macrophages had no effect on IL-12p40 production. These findings suggest that XF may be used in controlling macrophages-mediated inflammatory diseases. 相似文献
110.
Widespread skin and soft-tissue infections due to two methicillin-resistant Staphylococcus aureus strains harboring the genes for Panton-Valentine leucocidin 总被引:9,自引:0,他引:9 下载免费PDF全文
Diep BA Sensabaugh GF Somboonna N Somboona NS Carleton HA Perdreau-Remington F 《Journal of clinical microbiology》2004,42(5):2080-2084
Infections caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging as a major public health problem. CA-MRSA has been associated previously with skin and soft-tissue infection (SSTI) and with carriage of staphylococcal cassette chromosome mec (SCCmec) type IV and the Panton-Valentine leucocidin (PVL) virulence factor. To assess the clonal distribution of PVL-carrying strains and the association with SSTI in the San Francisco Bay area, we surveyed six collections of S. aureus isolates-671 isolates in all-collected between 1997 and 2002 originating from inpatient and outpatient clinical specimens and from a community-based sampling. Isolates were genotyped by pulsed-field gel electrophoresis, multilocus restriction fragment typing, and multilocus sequence typing and assayed for the PVL virulence factor. The S. aureus populations showed a high proportion of PVL-carrying strains, with frequencies ranging up to 70% in MRSA isolated from jail inmate patients and 69% in MRSA from patients receiving surgical treatment at an outpatient clinic specializing in treating SSTIs. PVL-carrying isolates were identified in nine clonal groups, but 88.5% of the PVL-carrying MRSA isolates belonged to only two clonal groups. These two clonal groups carried the SCCmec type IV resistance determinant and were more likely than other clonal groups to be recovered from SSTI sites than from other sites (P < 0.0001). There is evidence of clonal replacement over the period from 1999 to 2002, with one of these two clonal groups being supplanted by the other. 相似文献