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A number of surgical clips and other metallic materials embedded within patients have ferromagnetic properties that present a potential hazard when in the strong fields associated with magnetic resonance imaging. Several types of magnetometers and metal detectors were investigated as possible pre-imaging screening devices. The sensitivities and costs of these devices are given. 相似文献
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105.
目的:高血压常伴有纤溶功能的异常,但其机制尚不清楚。本研究拟观察高静水压培养对人脐静脉内皮细胞(HUVECs)t-PA和PAI-1的影响以及卡托普利的干预效果,并探讨其可能的作用机制。方法:选用第4~6代HU-VECs,接种于24孔培养板中。依培养压力分为3组:大气压组(0mmHg),中压组(90mmHg),高压组(180mmHg)。在同一压力组,根据不同药物干预又分为两个亚组。即对照组(Ctrl)和卡托普利组(Cap,10^-5mol/L)。每组6份标本。采用ELISA法测定上清液t-PA和PAI-1的抗原浓度,并用细胞内总蛋白进行标化(单位:ng/μg proteins)。同时测定细胞内Ca^2+浓度(nmol/L)。结果:与大气压组相比,中压和高压组t-PA浓度均显著降低,PAI-1浓度显著增高,t-PA/PAI-1比值显著降低,[Ca^2+]i也显著增高。卡托普利对大气压组的t-PA、PAI-1和[Ca^2+]i无显著影响,但在两个高压组,卡托普利显著升高t-PA浓度,显著降低PAI-1浓度,t-PA/PAI-1比值显著升高,[Ca^2+]i显著地降低。结论:高静水压可损害内皮细胞的纤溶功能,而卡托普利的干预可降低高压所升高的[Ca^2+]i,并改善高静水压对内皮细胞纤溶功能的影响。 相似文献
106.
PR Hunziker S Smith M Scherrer-Crosbie N Liel-Cohen RA Levine R Nesbitt SA Benton MH Picard 《Circulation》1999,99(5):1-6
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging. 相似文献
107.
Eight cases of dermatomyositis in children admitted to Scottish hospitals between 1962 and 1972 have been reviewed. 6 of the 8 were currently in complete remission. In the other 2 cases the disease remained active in 1 and 1 had died of cardiac failure 6 years after the onset of disease. 5 had developed extensive soft tissue calcification for which 2 were treated with ethanehydroxydiphosphonate, one showing definite improvement and the other no change. All had been treated with corticosteroids and two in addition had had cytotoxic agents (methotrexate or cyclophosphamide). The overal prognosis had probably been improved by the use of corticosteroids but not by the cytotoxic drugs. Only one of the patients was incapacitated by residual contractures or calcinosis. 相似文献
108.
Mohd Wamique Wahid Ali D. Himanshu Reddy Preeti Vishwakarma Mohd Waseem 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2018,12(6):843-847
Aim
To evaluate the serum paraoxonase 1 activity and determine its association with duration in type 2 Diabetes mellitus patients.Methods
A total of 80 cases from type 2 diabetes mellitus and healthy controls were enrolled in the present case control study. Human serum PON1 concentration was measured by ELISA and western blotting and it activity was determined spectrophotometrically using 4-nitrophenyle acetate. Diagnostic accuracy of serum PON1 to identify type 2 Diabetes mellitus was calculated with ROC analysis.Result
Serum concentration of LDL, VLDL, TG, A1C, FBS and TC levels showed significantly higher levels in type 2 diabetes patients as compared to healthy controls, however there were no significant differences found in the level of HDL. Serum PON1 concentration and activity monitored in patients with >1?year diabetes showed higher level (75.1?±?6.8?ng/mL) as compared to patients with >3?years diabetes (65.24?±?1.6?ng/mL), its level was further decreased in patients with >5 (53.8?±?2.6?ng/mL) and >7?years (48.1?±?2.7?ng/mL) of diabetes. PON1 concentration decreased as the duration of diabetes increased. PON1 level was further decreased due to habits like smoking and alcohol consumption.Conclusion
Serum PON1 levels decrease in states of high oxidative stress like metabolic syndrome, obesity, uncontrolled diabetes, and dyslipidemia. It can be used as diagnostic marker for diabetes mellitus along with increased TG, LDL, VLDL and FBG. 相似文献109.
Lauener RP; Huttner S; Buisson M; Hossle JP; Albisetti M; Seigneurin JM; Seger RA; Nadal D 《Blood》1995,86(4):1400-1407
One mechanism proposed to play a role in T-cell depletion in human immunodeficiency virus (HIV) infection is apoptosis (activation-induced cell death). We assessed whether apoptosis is related to activation of T cells in vivo and its possible triggers. DNA was extracted from peripheral blood mononuclear cells (PBMC) taken from 16 vertically HIV- infected children and 9 HIV-negative children born to HIV-positive mothers (controls) and tested by agarose gel electrophoresis for the presence of DNA fragments specific for apoptosis. Signs of apoptosis were found on in vitro culture of PBMC from 12 of 16 HIV-infected children, but not in PBMC from the nine controls. Eleven of the 12 HIV- infected children with apoptosis showed an elevated (> 15%) proportion of CD3+/HLA-DR+ cells. This was due to an increased proportion of CD8+/HLA-DR+ cells, as shown in 7 of 7 further tested patients. In none of the probands an increased (> 5%) proportion of IL-2 receptor expressing CD3+ cells was found. T cells undergoing apoptosis were preferentially of the CD8+ phenotype. Expansion of circulating CD8+/interleukin-2 receptor (IL-2R)-/HLA-DR+ T cells is known to occur during active infection with herpes viruses. To investigate the possible role of herpes viral coinfections for apoptosis in HIV infection, we focused on Epstein-Barr virus (EBV) as an example for a herpes virus usually acquired during childhood. In 10 of 12 patients with apoptosis, we found increased levels of EBV genome in PBMC and/or tissues, indicating active EBV replication. By contrast, no increased burden of EBV was found in the four HIV-infected patients without apoptosis or in the controls. Our data indicate that in children the occurrence of apoptosis in HIV infection is closely related to activation of CD8+ T cells. Furthermore, primoinfection with or reactivation of herpes viruses, such as EBV, may substantially contribute to such T-cell activation and the ensuing apoptosis. Additional studies are warranted to evaluate the contribution of herpes virus-triggered apoptosis to the T-cell loss leading to the acquired immunodeficiency syndrome. 相似文献
110.
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis. 相似文献