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141.
The stimulation by ADP or arachidonic acid of the aggregation of human platelets in plasma was inhibited by 4-hydroxynonenal (HNE). This reduction of aggregation was time related, and was increased by prolonged preincubation of the platelets with the aldehyde. HNE was more potent than its homologue 4-hydroxypentenal (HPE). HNE was less active in decreasing the aggregation induced by calcium ionophore A23187 or collagen in comparison with ADP. HNE was inactive against aggregation of platelet-rich plasma (PRP) stimulated by thrombin whereas it potently inhibited the aggregation of washed platelets in response to both thrombin and collagen. Platelets were found to degrade HNE, and mechanisms additional to covalent binding to glutathione are indicated by the results obtained. The aldehydes, including HNE, generated by platelets originated principally from arachidonic acid metabolism.  相似文献   
142.
BackgroundLarge variability in tests and differences in scoring systems used to study central coherence in eating disorders may lead to different interpretations, inconsistent findings and between study discrepancies. This study aimed to address inconsistencies by collating data from several studies from the same research group that used the Rey Osterrieth Complex Figure Test (Rey Figure) in order to produce norms to provide benchmark data for future studies.MethodData was collated from 984 participants in total. Anorexia Nervosa, Bulimia Nervosa, recovered Anorexia Nervosa, unaffected family members and healthy controls were compared using the Rey Figure.ResultsPoor global processing was observed across all current eating disorder sub-groups and in unaffected relatives. There was no difference in performance between recovered AN and HC groups.ConclusionsThis is the largest dataset reported in the literature and supports previous studies implicating poor global processing across eating disorders using the Rey Figure. It provides robust normative data useful for future studies.  相似文献   
143.
Six patients with biopsy-proven renal sarcoidosis presented with renal failure of unknown origin; in none was the diagnosis of sarcoidosis initially considered. The serum creatinine concentration at the time of presentation ranged from 265 to 1380 μmol/l (3.0 to 15.6 mg/dl), with a mean of 787 μmol/l (8.9 mg/dl). Although only two patients were hypercalcemic at the time of presentation, the 24-hour urinary excretion of calcium was increased in three of the four patients in whom it was measured, and renal calculi were present in one case. Renal biopsy revealed interstitial nephritis and tubular atrophy in all cases, as well as nephrocalcinosis in three cases and noncaseating granulomas negative for acid-fast bacilli in four cases. In each patient steroid therapy led to a rapid improvement in renal function (mean post-treatment serum creatinine level 274 μmol/l [3.1 mg/dl]). The follow-up period ranged from 8 months to 8 years (mean 3.0 years). In three patients renal function remained stable with low-dose steroid therapy. In two cases recurrent hypercalcemia and deteriorating renal function accompanied steroid withdrawal but resolved with its reinstitution. In one additional case reversible deterioration in renal function accompanied tapering of the steroid dose; however, there was no hypercalcemia.This report emphasizes the importance of considering sarcoidosis in the differential diagnosis of acute renal failure of unknown origin. Long-term follow-up of such patients is essential, as relapse is common.  相似文献   
144.
银屑病是一种慢性易复发的炎性皮肤疾病,为了探讨新型小分子化合物FMS样的酪氨酸激酶3(fms-like tyrosine kinase 3,FLT3)抑制剂对银屑病的治疗作用,采用了小鼠尾部鳞片表皮颗粒层形成模型,分别进行口服及外用给药,并取尾部皮肤制作病理切片,计算有颗粒层形成的鳞片数。结果显示:口服给药及外用给药组小鼠尾部鳞片颗粒细胞数均显著高于空白对照组(P0.01),同时实验组小鼠颗粒细胞体积增大,胞浆内颗粒粗大且染色较深,细胞分界清楚,细胞核及核仁明显,但是各实验组内不同浓度间差异不显著,此外口服给药及外用给药组小鼠内脏器官均未出现明显的毒副作用。以上结果说明该新型小分子化合物FLT3抑制剂能使小鼠尾部鳞片颗粒细胞显著增多,而且口服和外用制剂均能有效拮抗银屑病,并对小鼠内脏器官无明显的毒副作用。  相似文献   
145.
用生物超微弱发光探测技术,对植物叶片的超微弱发光透过滤波片进行测量,并用量子光学中的光子计数分布统计方法得到的结果表明,不同波长下,大光金鱼花叶片的光子计数分布不同,但幼叶和老叶的光子计数分布的规律基本相同,而成熟叶片光子计数分布的规律比较紊乱。  相似文献   
146.

Background

Because mitochondria play an essential role in energy metabolism, generation of reactive oxygen species (ROS), and apoptosis, sequence variation in the mitochondrial genome has been postulated to be a contributing factor to the etiology of multifactorial age-related diseases, including cancer. The aim of the present study was to compare the frequencies of mitochondrial DNA (mtDNA) haplogroups as well as control region (CR) polymorphisms of patients with malignant melanoma (n = 351) versus those of healthy controls (n = 1598) in Middle Europe.

Methodology and Principal Findings

Using primer extension analysis and DNA sequencing, we identified all nine major European mitochondrial haplogroups and known CR polymorphisms. The frequencies of the major mitochondrial haplogroups did not differ significantly between patients and control subjects, whereas the frequencies of the one another linked CR polymorphisms A16183C, T16189C, C16192T, C16270T and T195C were significantly higher in patients with melanoma compared to the controls. Regarding clinical characteristics of the patient cohort, none of the nine major European haplogroups was associated with either Breslow thickness or distant metastasis. The CR polymorphisms A302CC-insertion and T310C-insertion were significantly associated with mean Breslow thickness, whereas the CR polymorphism T16519C was associated with metastasis.

Conclusions and Significance

Our results suggest that mtDNA variations could be involved in melanoma etiology and pathogenesis, although the functional consequence of CR polymorphisms remains to be elucidated.  相似文献   
147.
记述采自记述中国三节叶蜂科三节叶蜂属1新种:白尾晴腹三节叶蜂Arge albocaudalica Wei,Yan et He.sp.nov..本种与Arge xanthogaster (Cameron,1876)很相似,但腹部黑褐色,端部2节背板和锯鞘黄白色;后翅臀窒柄短于后翅M室长,锯鞘背面观内侧切口很小,深度明显短于锯鞘侧叶端部宽;锯腹片14刃,第2节缝最长粗刺毛约等长于锯节宽度的3/4,节缝粗毛每节约9个,第8节缝最长粗刺毛等宽于该处锯节宽.定义了Arge xanthogaster种团,编制了该种团东亚地区已知种类检索表.  相似文献   
148.
研究神经营养因子Neurturin(NTN)在由于神经元损伤而造成的神经退行性疾病中对神经元的保护和修复作用。利用重组腺病毒载体将NTN基因转入恒河猴骨髓间充质干细胞(rMSC),通过RT-PCR、IF及Western blot方法检测NTN的转录和表达,并采用鸡胚背根神经节体外培养实验和胚胎大鼠中脑多巴胺能神经元存活实验对NTN进行体外活性检测。结果表明NTN在rMSC中稳定表达和分泌,并具有体外生物学活性,为由于神经元损伤造成的神经退行性疾病的干细胞移植治疗奠定了一定的基础。  相似文献   
149.
医学超声治疗原理及其临床应用研究   总被引:3,自引:0,他引:3  
本文从超声波对人体特有的生物效应出发,用生物医学工程的观点,阐述了现代超声治疗技术基本原理及最新临床应用成果,特别是在超声外科治疗技术中的最新发展,展望了超声治疗技术的应用发展前景。  相似文献   
150.
根据土壤氮素解吸模型,通过盆栽试验研究解吸特征参数对土壤渗漏水硝态氮浓度的影响.结果表明:土壤氮素可解吸量Q、土壤溶液氮初始浓度Cli和C1/比值与土壤渗漏水硝态氮浓度呈非线性关系,在较低氮解吸特征值时则呈线性关系,由此提出“双速率转折点”概念评价土壤硝态氮流失潜能.当耕层土壤氮素解吸特征值超过“双速率转折点”X0时,硝态氮浓度的增加速率将以非线性形式迅速提高,反之将稳定在较低水平.  相似文献   
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