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981.
Ten cases of pediatric fulminant hemophagocytic syndrome, encountered between 1986 and 1989, are described. They occurred in the summer, and the patients presented with fever, jaundice, hepatosplenomegaly, pancytopenia, coagulopathy, and abnormal liver function. Bone marrow studies revealed infiltration by atypical T-lymphoid cells, rare B immunoblasts, and mature histiocytes with hemophagocytosis. Initially, histiocytic medullary reticulosis was suspected in six cases. The clinical course was characterized by rapid deterioration, with a mean period of 16 days from onset of fever to death. The main causes of death were coagulopathy with multiple organ failure and opportunistic infection. In seven of eight cases studied by serologic assay and Southern blot hybridization, acute or active Epstein-Barr virus (EBV) infection was documented. It is suggested that an atypical or fulminant form of primary EBV infection distinct from classic infectious mononucleosis was prevalent in previously healthy children in Taiwan. Younger age involvement and seasonal clustering were characteristic of the disorder described.  相似文献   
982.
鲍善芬  李寒濂 《营养学报》1994,16(4):401-405
对我院老年病房四季112份全膳食中的15种元素(钾、钠、钙、磷、镁、锌、铜、铁、锰、硒、铝、钴、铬、钼、镍)进行了实测。结果表明:钾的平均日摄入量为1809+38mg,接近RDA值的下限;钠的平均日摄入量为5972±146mg远高于1100~3300mg的供给标准。钙、磷、镁的日摄入量已达到了RDA值的标准。全膳食中锌、铜的含量分别为11.68±0.19mg和1.72±0.10rng,略低于RDA值(15mg及2~3mg)的标准,锰含量为3.41±0.09mg硒为98±2.5μg,都处于安全与适宜摄入范围(2.5~5.0mg和50~200μ9)。钴、铬、钼、镍均为人体必需的微量元素、目前我国尚未建立有关营养供给量标准。该项研究结果可为今后确定其推荐供给量标准提供必要的基础资料.  相似文献   
983.
984.
The mistreatment of elderly is subject to various social constructions. On two geographically distinct Plains Indian Reservations which we call Lone Mountain and Abundant Lands, the abuse or neglect of elderly is construed as a health problem which is a dysfunction of the community as a whole. Both physical abuse and neglect are more common on the Lone Mountain Reservation, occurring in association with other indicators of community disorganization such as unemployment and substance abuse. On the Abundant Lands Reservation physical abuse was categorically denied and what neglect existed appeared to be a function of role strain, geographic dispersal, climate and terrain. We attribute differences in the prevalence of mistreatment of elders to variations in economic opportunities for younger residents. Examining the historical and present contexts of intergenerational relationships on the reservations, we discuss the implications of this study for social exchange theory and policy applications.This research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America Applied  相似文献   
985.
Histological examination of the deciduous teeth in two cases of segmental odontomaxillary dysplasia (SOMD) showed fibrous enlargement of the pulps, an irregular pulp/dentine interface displaying many pseudoinclusions and pulp stones. There were tubular defects in the coronal dentine from pulp horn to cusp tip, an irregular tubular structure to the circumpulpal dentine of the apical half, a focally deficient odontoblast layer and widespread external resorption. Together with the clinical features of unilateral maxillary enlargement, upper alveolar expansion in the distal segment, increased spacing and delayed eruption of the deciduous molars and absence of premolar teeth, these histological appearances allow distinction of this condition from fibrous dysplasia (FD), segmental hemifacial hypertrophy (SHH) and regional odontodysplasia (ROD).  相似文献   
986.
987.
利多卡因对大鼠离体气管平滑肌的作用及机制   总被引:5,自引:0,他引:5  
目的:研究利多卡因对气管平滑肌的作用及机制.方法:观察利多卡因对乙酰胆碱(ACh)和高钾预收缩大鼠离体气管的作用,对ACh、高钾和CaCl2诱发气管平滑肌收缩作用剂量反应曲线和ACh致两种收缩组分的影响并与维拉帕米进行比较.结果:利多卡因对ACh和高钾诱发的大鼠离体气管平滑肌标本收缩有舒张作用,并不被L-NAME和普萘洛尔阻断.利多卡因浓度依赖性地使ACh、KCl和CaCl2对大鼠离体气管条标本的量效反应曲线右移,最大反应降低.利多卡因0.69和3.45 mmol/L对ACh所致依赖细胞内钙收缩的抑制率及依赖细胞外钙收缩的抑制率差别均十分显著(P<0.01).结论:利多卡因对离体大鼠气管平滑肌的舒张作用可能是通过非特异性地抑制细胞外钙经电压调节和受体调节钙通道向内流动及抑制细胞内钙释放来实现的.  相似文献   
988.
In erythropoietic protoporphyria (EPP), there is excessive production of protoporphyrin, primarily in the bone marrow, resulting in increased biliary excretion of this heme precursor. Some patients will develop progressive liver disease that may ultimately require liver transplantation. However, excessive production of protoporphyrin by the bone marrow continues after transplantation, which may cause recurrent disease in the allograft. This study was performed to define post-transplant survival, the risk of recurrent disease, and specific management issues in patients transplanted for EPP liver disease. The patients studied consisted of twelve males and eight females, with an average age of 31 (range, 13-56) years at the time of transplantation. The estimated maximum MELD score prior to transplant was 21 (range, 15-29). Unique complications in the perioperative period were light induced tissue damage in four patients and neuropathy in six, requiring prolonged mechanical ventilation in four. Patient and graft survival rates were 85% at 1 year, 69% at 5 years, and 47% at 10 years. Recurrent EPP liver disease occurred in 11 of 17 patients (65%) who survived more than 2 months. Three patients were retransplanted at 1.8, 12.6, and 14.5 years after the initial transplant for recurrent EPP liver disease. In conclusion, the 5-year patient survival rate in patients transplanted for EPP liver disease is good, but the recurrence of EPP liver disease appears to diminish long term graft and patient survival.  相似文献   
989.
To determine the single- and multiple-dose ceftazidime kinetics, we administered ceftazidime, 2 gm intravenous bolus every 12 hours, to 14 infected Chinese patients with various degrees of renal function. Blood samples were drawn in serial after the first and 7th dose and serum ceftazidime concentrations were measured by high pressure liquid chromatography. Ceftazidime concentration-time data were fitted to a two-compartment model with a nonlinear regression program. Ceftazidime kinetics was unaltered by repeated dosing. Both total body clearance and elimination rate constant of ceftazidime decrease significantly in proportion to the creatinine clearance estimated by Bjornsson's method. Renal insufficiency did not modify the steady-state volume of distribution (Vdss) of ceftazidime which, however, appeared to be larger than those reported previously. This larger Vdss may be explained by acute infection process, confinement to bed, and increased extracellular fluid volume as a result of hypoalbuminemia. Our study indicates the estimated creatinine clearance as a useful guide to ceftazidime dosage adjustment and also emphasizes the clinical relevance of conducting kinetic studies of antibiotics in infected patients.  相似文献   
990.
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