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11.
Background and purposeFlow diverters are increasingly used to treat intracranial aneurysms. We report the safety and efficacy of the p64 flow diverter, a resheathable and detachable device for intracranial aneurysms.Materials and methodsWe retrospectively reviewed 108 patients with 109 aneurysms treated with the p64 between March 2014 and July 2019. There were 87 women and 21 men, mean age 57 years. Of 109 aneurysms, 74 were discovered incidentally, 12 were symptomatic, 18 were previously treated, and five were ruptured dissection aneurysms. A total of 10 aneurysms were located in the posterior circulation. The mean aneurysm or remnant size was 8.1 mm.ResultsHemorrhage by perforation with the distal guidewire occurred in two patients with permanent neurological deficits in one. In one patient, acute in-stent occlusion caused infarction with a permanent deficit. Permanent morbidity was 1.9% (2 of 108, 95%CI 0.1–6.9%); there was no mortality. During follow-up, three in-stent occlusions occurred, all asymptomatic. There were no delayed hemorrhagic complications. At six months, 77 of 96 aneurysms (80.2%) were completely occluded, and at last follow-up, this increased to 93 of 96 aneurysms (96.9%). In-stent stenosis at any degree occurred in 11 patients, progressing to asymptomatic complete occlusion in one. In the other patients, stenosis resolved or improved at further follow-up.ConclusionThe p64 offers an effective and safe treatment option. Aneurysm occlusion rate was 97% at last follow-up, mostly achieved with a single device. There were no delayed hemorrhagic complications. Delayed in-stent stenosis infrequently progresses to occlusion but remains a matter of concern.  相似文献   
12.
Temporal arteritis (TA), or giant cell arteritis, is a systemic autoimmune vasculitis affecting patients over 50 years of age. It can cause rapid, irreversible bilateral vision loss in older adults and is therefore considered an ophthalmological emergency. Many of the symptoms and signs of TA can be vague, non-specific and gradual in onset, often leading to a delayed or inaccurate diagnosis. As such, it is important for a wide variety of primary optometrists and health practitioners to maintain a robust understanding of the clinical presentation, key investigations and time-sensitive management of this disease, as early initiation of treatment for TA can be vision- and life-saving.  相似文献   
13.

Purpose

The current project was undertaken with the aim to propose and test an in-depth integrative analysis of neuropharmacokinetic (neuroPK) properties of new chemical entities (NCEs), thereby optimizing the routine of evaluation and selection of novel neurotherapeutics.

Methods

Forty compounds covering a wide range of physicochemical properties and various CNS targets were investigated. The combinatory mapping approach was used for the assessment of the extent of blood-brain and cellular barriers transport via estimation of unbound-compound brain (Kp,uu,brain) and cell (Kp,uu,cell) partitioning coefficients. Intra-brain distribution was evaluated using the brain slice method. Intra- and sub-cellular distribution was estimated via calculation of unbound-drug cytosolic and lysosomal partitioning coefficients.

Results

Assessment of Kp,uu,brain revealed extensive variability in the brain penetration properties across compounds, with a prevalence of compounds actively effluxed at the blood-brain barrier. Kp,uu,cell was valuable for identification of compounds with a tendency to accumulate intracellularly. Prediction of cytosolic and lysosomal partitioning provided insight into the subcellular accumulation. Integration of the neuroPK parameters with pharmacodynamic readouts demonstrated the value of the proposed approach in the evaluation of target engagement and NCE selection.

Conclusions

With the rather easily-performed combinatory mapping approach, it was possible to provide quantitative information supporting the decision making in the drug discovery setting.  相似文献   
14.
Neutrophils isolated from cancer patients treated with granulocyte colony-stimulating factor (G-CSF) express high levels of Fc gamma RI. They exhibited an efficient killing of GD2+ neuroblastoma cells in the presence of an antidisialoganglioside (GD2) mouse monoclonal antibody (MoAb; 7A4, IgG3 kappa). However, this cytotoxicity was totally blocked by human monomeric IgG. In contrast, a bispecific antibody (7A4 bis 22/MDX-260), prepared by chemically linking an F(ab') fragment of 7A4 with an F(ab') fragment of an anti-Fc gamma RI MoAb, 22, which binds outside the Fc binding domain, triggered antibody-dependent cell cytotoxicity, even when neutrophils were preincubated with human monomeric IgG. F(ab')2 22 MoAb abrogated the MDX-260 killing without affecting that of 7A4. The 3G8 MoAb, directed against the Fc gamma RIII binding site, did not inhibit the cytotoxicity induced by either antibody. Thus, these results indicate that G-CSF-activated neutrophils exert their cytotoxic effect against neuroblastoma cells through Fc gamma RI and not Fc gamma RIII, and that the saturation of the high affinity Fc gamma RI by monomeric IgG can be overcome by the use of bispecific antibodies binding epitopes outside the IgG Fc gamma RI binding site. A combined administration of such bispecific antibodies and G-CSF may be, therefore, an efficient therapeutic approach to trigger tumor lysis by cytotoxic neutrophils in vivo.  相似文献   
15.
Heterogeneity of B cell involvement in acute nonlymphocytic leukemia   总被引:2,自引:0,他引:2  
In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis.  相似文献   
16.
推广规范化的胃癌淋巴结清扫术   总被引:5,自引:1,他引:4  
胃癌外科治疗的历史始自Billroth1881年在维也纳为胃癌患者成功施行世界上第1例胃切除,距今已近120a.本世纪初,胃癌是癌肿的头号杀手(theleadingcancerkiller).最近几十年,全球的胃癌病死率有所下降,但我国农村幅员广阔,农村人口比例高,目前胃癌的病死率仍居各种肿瘤的首位.最近20a~30a,以日本为代表的胃癌的外科治疗已经获得长足的进步.我国胃癌的外科诊治水平也有明显的提高[1],根治性切除率、早期胃癌比率以及5年生存率均有明显提高,手术死亡率及并发症发生率明显下降…  相似文献   
17.
目的:分析不同载荷对C4~5椎间孔孔径变化的影响。方法:实验于2006-01/2006-05在湘南学院附属医院进行。成人新鲜尸体颈椎标本10具(自愿捐献或家属同意),节段包括C3~T1,剔除肌肉组织,保留椎间盘、韧带和关节囊结构的完整。分别测量椎间盘完整、椎间盘髓核摘除、颈人工椎间盘置换和前路钢板植骨内固定4种状态下,加压速度为5mm/min时,25,50,75,100,125和150N的分级轴向载荷加载于标本时C4~5上下径、上前后径、下前后径以及椎间孔面积的变化。结果:①轴向加载25N时,C4~5椎间孔面积椎间盘髓核摘除标本小于完整椎间盘、颈人工椎间盘置换和前路钢板植骨内固定标本[(57.26±17.65),(65.81±16.83),(75.37±17.75),(66.21±16.50)mm2,P<0.05];颈人工椎间盘置换标本大于颈椎植骨融合钢板内固定标本(P<0.05)。②轴向加载50N时,C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(57.13±17.64),(65.72±16.85),(75.35±17.75),(66.11±16.46)mm2,P<0.05];颈人工椎间盘置换标本大于颈椎植骨融合钢板内固定标本(P<0.05)。③轴向加载75N时,上下径:C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(55.26±17.66),(64.80±16.85),(73.32±17.74),(65.21±16.48)mm2,P<0.05];颈人工椎间盘置换标本大于颈椎植骨融合钢板内固定标本(P<0.05)。④轴向加载100N时,上下径:C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(53.22±17.66),(63.81±16.83),(71.35±17.76),(65.27±16.46)mm2,P<0.05]。⑤轴向加载125N时,C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(51.25±17.64),(62.82±16.83),(69.25±17.74),(65.25±16.43)mm2,P<0.05]。⑥椎间孔面积:轴向加载150N时,C4~5椎间孔面积椎间盘髓核摘除标本小于其他3组[(49.16±17.65),(61.84±16.86),(67.15±17.73),(65.24±16.42)mm2,P<0.05]结论:颈椎间盘髓核摘除后C4~5椎间孔有效空间明显减少。  相似文献   
18.
人羊膜间充质细胞具有分化成软骨及成骨细胞的潜能   总被引:1,自引:0,他引:1  
目的:人羊膜间充质细胞具有比骨髓间充质干细胞更强的扩增能力和免疫原性低等优势。建立体外适宜的诱导培养条件,观察人羊膜间充质细胞定向分化为软骨细胞和成骨细胞的能力。方法:实验于2005-09/2006-12在贵州省细胞工程重点实验室完成。①材料来源:经产妇知情同意,无菌采集健康足月分娩新生儿胎盘6份,实验经医院医学伦理委员会批准。②实验方法:采用机械法剥离羊膜组织,二步酶消化法分离收获人羊膜间充质细胞,按2.2×10~8L~(-1)密度接种,传至第1~2代用于诱导分化实验。向软骨细胞诱导分化时,人羊膜间充质细胞按3×10~8L~(-1)密度接种,诱导培养液为含体积分数0.01的胎牛血清、10 mg/L转化生长因β1、100 nmol/L地塞米松、50 mg/L抗坏血酸、1%培养基添加物。向成骨细胞诱导分化时,人羊膜间充质细胞按6×10~7L~(-1)密度接种,诱导培养液为含体积分数0.1的胎牛血清、100 nmol/L地塞米松、50 mg/L抗坏血酸、5 mmol/Lβ-甘油磷酸。③实验评估:原代细胞用流式细胞仪分析表型,免疫细胞化学染色进行波形蛋白表达鉴定。分别于体外诱导第7,14,21,28天采用免疫细胞化学法检测软骨特异性Ⅱ型胶原的表达,细胞化学法检测蛋白聚糖的表达,钙-钴法检测成骨细胞特异性碱性磷酸酶的表达,茜素红S检测钙盐沉积情况。结果:①免疫组化与表型特征:人羊膜间充质细胞高表达间充质干细胞表面标志CD29、CD44和间充质细胞标志波形蛋白。②向软骨细胞诱导分化:诱导14 d后,人羊膜间充质细胞由长梭型逐渐变为多角形,可检测到Ⅱ型胶原蛋白表达及软骨细胞特异性细胞外基质蛋白聚糖。③向成骨细胞诱导分化:诱导21 d后,可观察到人羊膜间充质细胞的胞浆内有碱性磷酸酶表达,且可见钙盐沉积。结论:人羊膜间充质细胞具有分化成软骨细胞和成骨细胞的特性,可作为骨及软骨组织工程种子细胞的新来源。  相似文献   
19.
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process.  相似文献   
20.
The UK 1990 height charts are derived from an up to date dataset and introduce a change in the centile lines, particularly the addition of the 0.4th centile. This study examined the likely impact of these changes. Height data from London school children (1990-1993) were examined using Tanner and Whitehouse (TW) and UK 1990 charts. Numbers of children with height below TW 3rd centile were compared with numbers below the UK 1990 3rd and 0.4th centiles. The TW charts identified only 1% of children below the TW 3rd centile, while the UK 1990 charts identified 3% below the 3rd and 0.4% below the 0.4th centiles. If the 3rd centile remains as the referral 'cut off' for short stature, the introduction of the UK 1990 charts would increase current workload two- to three-fold, while a change to the 0.4th centile would reduce it by 50%. A significant number of children with abnormalities may be excluded from further assessment as a result of this latter change. In this small scale community study it is not possible to assess the consequences of this change. The heights at diagnosis of children with growth hormone (GH) deficiency (peak GH < 20 mU/l during a standard provocation test) were therefore compared to the 0.4th centile (UK 1990 charts). Sixty eight children with heights < 2nd centile (UK 1990 charts) currently receiving GH replacement (17 female, 51 male, aged 9.7, SD 3.5, years) were assessed, and of these, 28 (41%) had heights at diagnosis between 0.4th and 2nd centile, with a mean height standard deviation score of -2.32 (SD 0.21). This suggests that if the 0.4th centile were to be used as the sole criterion for referral for slow growth, a significant proportion of children with abnormality would not be referred for further assessment. The UK 1990 2nd centile should replace the TW 3rd centile. Children below this should undergo an intermediary medical assessment to confirm height measurement, to exclude from referral children with mild familial short stature and to identify concerns regarding the child.  相似文献   
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