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991.
992.
Molecular refinement of the 1p36 deletion syndrome reveals size diversity and a preponderance of maternally derived deletions 总被引:8,自引:0,他引:8
Wu YQ; Heilstedt HA; Bedell JA; May KM; Starkey DE; McPherson JD; Shapira SK; Shaffer LG 《Human molecular genetics》1999,8(2):313-321
The deletion of chromosome 1p36 is a newly recognized, relatively common
contiguous gene deletion syndrome with a variable phenotype. The clinical
features have recently been delineated and molecular analysis indicates
that the prevalence of certain phenotypic features appears to correlate
with deletion size. Phenotype/genotype comparisons have allowed the
assignment of certain clinical features to specific deletion intervals,
significantly narrowing the regions within which to search for candidate
genes. We have extensively characterized the deletion regions in 30 cases
using microsatellite markers and fluorescence in situ hybridization
analyses. The map order of 28 microsatellite markers spanning the deletion
region was obtained by a combination of genotypic analysis and physical
mapping. The deletion region was divided into six intervals and breakpoints
were found to cluster in mainly two regions. Molecular analysis of the
deletions showed that two patients had complex re-arrangements; these cases
shared their distal and proximal breakpoints in the two common breakpoint
regions. Of the de novo deletions ( n = 28) in whichparental samples were
available and the analysis was informative ( n = 27), there were
significantly morematernally derived deletions ( n = 21) than paternally
derived deletions ( n = 6) (chi1(2) = 8.35, P < 0.0001).
Phenotype/genotype correlations and refinements of critical regions in our
naturally occurring deletion panel have delineated specific areas in which
to focus the search for the causative genes for the features of this
syndrome.
相似文献
993.
We report a case of renal capsular artery pseudoaneurysm caused by percutaneous renal biopsy. The injury was diagnosed and treated with arteriography and transarterial embolization. Because the arterial injury was extraparenchymal, the clinical manifestations of blood loss were flank pain and decreasing hematocrit without hematuria. Injury to renal capsular arteries during percutaneous renal biopsy is a rare possibility because of their small size. 相似文献
994.
Circulating eosinophil/basophil progenitors and nasal mucosal cytokines in seasonal allergic rhinitis 总被引:3,自引:0,他引:3
M Linden C Svensson M Andersson L Greiff E Andersson JA Denburg CGA Persson 《Allergy》1999,54(3):212-219
Accumulation of eosinophils in the airways is characteristic of allergic rhinitis and asthma. The tissue eosinophilia may involve both recruitment of mature eosinophils and proliferation of their progenitors. This study examines mature eosinophils (nasal and circulating), their circulating progenitors, and a potential role of granulocyte-macrophage colony-stimulating factor (GM-CSF) in stimulating these progenitors. Twelve subjects with a history of seasonal allergic rhinitis and positive skin prick test for birch pollen were studied during four periods: shortly before, in the early and intense phase, at the end, and well after the Swedish birch-pollen season. Nasal mucosal and circulating eosinophils were examined in both nasal brushings and peripheral blood samples. Eosinophil/basophil progenitors were determined by counting colony-forming units in nonadherent mononuclear blood-cell cultures in methylcellulose at 14 days. The nasal mucosal cytokines GM-CSF, interleukin (IL)-1beta, IL-3, IL-5, IL-6, IL-8, and RANTES were analyzed (ELISA) in nasal lavage (NAL) fluids. All patients developed severe symptoms of rhinitis at the height of the season, with increased numbers of eosinophils in the nasal mucosa (P<0.05) and in the circulation (P<0.05). At this time point, the number of circulating progenitors (P<0.05) and the NAL fluid level of GM-CSF (P<0.05) were also increased. In contrast, there was no change in the NAL fluid levels of IL-1beta, IL-3, IL-6, or IL-8. Neither IL-5 nor RANTES could be detected in any of the NAL fluids. At the end of or after the season, there was no increase in nasal eosinophils or circulating eosinophils or progenitors (P>0.05). Ex vivo addition of GM-CSF (10-100 U) increased the number of blood progenitors grown before (P<0.01) and after (P<0.05) the season, compared with during the season. The in vitro GM-CSF responsiveness of progenitors may be related to whether or not these already have been stimulated endogenously by GM-CSF. Taken together, our data thus suggest that GM-CSF may play a role in vivo to increase production of eosinophilic progenitors in allergic airway disease. 相似文献
995.
目的分析创伤性动静脉瘘(AVF)的临床特点、造影表现、造影技术及治疗方式的选择。方法回顾性分析纽约Kings County医疗中心25年间全部确诊的108例创伤性AVF的介入相关诊疗资料。分析内容包括患者外伤种类、临床表现、损伤部位、血管造影异常特征、AVF血流动力学特征(分5个类型)、治疗方式的选择等。结果 108例患者中共发现117处AVF,大多数患者临床特征不明确。创伤种类包括枪伤(导致72处AVF)、刺伤(24处)、钝性伤(8处)、高处坠落伤(3处)、医源性损伤(2处)。损伤部位常见于肢体(46例)、颈部(19例)、肝脏(13例)和锁骨下血管(11例)。所有病变均可见静脉早显,显示动脉横断52处,撕裂37处,49.6%的AVF与假性动脉瘤有关。最常见的血流特点是Ⅰ型,即瘘口所在的动脉近段和远段、静脉的近段和远段都显示,伴远侧段静脉瓣功能不全,共40处瘘(34.2%),其次是Ⅲ型22个(18.8%),Ⅴ型最不常见(4.3%)。34例接受手术治疗,61例栓塞治疗,7例临床观察。分别采用弹簧圈(47例)、明胶海绵(9例)、无水乙醇(3例)、可脱球囊(2例),其中弹簧圈效果理想、并发症少。6例采用覆膜支架效果好。结论血管造影是诊断创伤性AVF的金标准,造影时准确观察动脉损伤的性质,瘘口的解剖和血流特点及所有进入瘘口的动脉分支,对于选择治疗方式及保证介入治疗的成功完成至关重要。 相似文献
996.
Silke F Metzelthin Ramon Daniëls Erik van Rossum Wim JA van den Heuvel Gertrudis IJM Kempen 《BMC public health》2010,10(1):176
Background
Frailty is highly prevalent in older people. Its serious adverse consequences, such as disability, are considered to be a public health problem. Therefore, disability prevention in community-dwelling frail older people is considered to be a priority for research and clinical practice in geriatric care. With regard to disability prevention, valid screening instruments are needed to identify frail older people in time. The aim of this study was to evaluate and compare the psychometric properties of three screening instruments: the Groningen Frailty Indicator (GFI), the Tilburg Frailty Indicator (TFI) and the Sherbrooke Postal Questionnaire (SPQ). For validation purposes the Groningen Activity Restriction Scale (GARS) was added. 相似文献997.
仲维清 Parkinson JA 唐文兵 张勇 Sadler PJ ZHONG Wei-qing TANG Wen-bing ZHANG Yong 《第二军医大学学报》2006,27(1):71-75
目的:测定人血清脱金属铁传递蛋白裂解焦磷酸键的反应速率常数.方法:应用31P NMR技术,在不同pH值及不同浓度MgCl2存在条件下,测定了脱金属铁传递蛋白与焦磷酸二钠反应的核磁共振图谱,根据焦磷酸盐的摩尔浓度(对应于其谱峰强度)随时间的变化情况,应用动力学公式对数据进行拟合.结果:当人血清脱金属铁传递蛋白(0.5~1.0 mmol/L)与焦磷酸盐的反应摩尔浓度比为15时,在312 K条件下,反应速率常数分别为:8.83×10-4 L·mmol-1·h-1(pH 6.85)、9.59×10-4 L·mmol-1·h-1(pH 7.40)和1.38×10-3 L·mmol-1·h-1(pH 8.15).在2 mmol/L MgCl2存在时,pH 7.40、312 K条件下,反应速率常数为1.21×10-3L·mmol-1·h-1.结论:人血清脱金属铁传递蛋白能缓慢地将焦磷酸根裂解为磷酸根,反应具有二级反应动力学性质,Mg2 对该裂解反应有弱催化作用. 相似文献
998.
脊髓损伤后一氧化氮含量及一氧化氮合酶活性的变化与脊髓水肿的关系 总被引:5,自引:1,他引:4
目的 :为了探讨脊髓损伤后一氧化氮 (NO)含量及其合酶 (NOS)活性与脊髓水肿的关系。方法 :测定不同程度脊髓损伤后NO含量及NOS活性的变化 ,同时测定脊髓组织含水量。结果 :随着损伤程度的增加 ,NO含量及NOS活性均增加 ,脊髓组织水肿增加。结论 :脊髓损伤后NO含量及NOS活性增加 ,与脊髓组织的水肿密切相关 ,提示NO参与了脊髓伤后的病理生理改变。 相似文献
999.
目的 比较甲基强的松龙 (MP)与胶质源性神经营养因子 (GDNF)的治疗脊髓损伤的疗效。方法 SD大鼠分成对照组、 MP组及 MP+ GDNF组,改良 Allen法撞击致伤 T13脊髓、尾静脉及蛛网膜下分别给予 MP和 GDNF,不同时间 Tarlov方法评定脊髓运动功能, 3周取脊髓标本测定脊髓残留面积。结果 脊髓损伤后治疗组评分明显低于对照组 (PMP组 >GDNF组 (P 0.05),但均高于 GDNF组 (P0.05),但仍明显低于对照组 (P 相似文献
1000.
5分钟短时心率变异性自回归模型频域分析的临床应用价值 总被引:1,自引:2,他引:1
目的:基于自回归模型5min心率变异性频域分析的临床价值,检验糖尿病患者5min短时心率变异性自回归模型分析频域指标的变化。方法:实验对象为50岁以上糖尿病患者9例和正常人7例,糖尿病史>6年7例,糖尿病史<3年2例。被试者采用坐姿,静息状态,测试30min的ECG信号,采样率为1000Hz。对每个样本取第10~15分钟的时长5min的RR间期作为心率变异性信号,进行基于自回归模型的频域分析。依据功率谱估计计算16例受试者的总能量,低频段能量,高频段能量,低频段高频段能量比值等指标参数。结果:通过对5min心率变异性自回归模型计算结果得出,糖尿病史>6年患者总能量、低频段能量、高频段能量低于正常人,差异有显著性意义(t=2.4952,2.7027,1.7299,P<0.05)。糖尿病史<3年患者总能量、低频段能量、高频段能量与正常人差异不明显。两类糖尿病患者与正常人低频段高频段能量比值无明显差异。结论:5min短时心率变异性自回归模型分析能够有效反映糖尿病患者自主神经的病变,可能成为检测自主神经病变的方法。 相似文献