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OBJECTIVES: Patients with Alzheimer's disease (AD) showing a selective impairment of episodic and semantic memory have recently been classified as affected by focal temporal lobe dysfunction (FTLD) and considered as a distinct subgroup of patients affected by a particular form of AD. The aim was to compare the cerebral perfusion of patients with AD with FTLD and patients with AD with the more typical profile of diffuse cognitive impairment (dAD). METHODS: Ten patients with AD with FTLD, 14 patients with AD with dAD, and 12 normal controls were studied. All the 24 patients with AD underwent a complete neuropsychological assessment. SPECT examination with [(99m)Tc]-HMPAO, using a four head brain dedicated tomograph, was performed in patients and controls. Tracer uptake was quantified in 27 regions of interest (ROIs), including lateral and mesial temporal areas. Mean counts in the 27 ROIs of controls, patients with FTLD and those with dAD were compared using an ANOVA for repeated measures with Bonferroni's correction. A logistic regression analysis, followed by a receiver operating characteristic (ROC) analysis, was also applied to select SPECT patterns which significantly differentiated patients with FTLD and those with dAD. RESULTS: Two scintigraphic patterns of abnormalities, shaping a double dissociation between the FTLD and dAD groups, emerged: a bilateral mesial temporal hypoperfusion, characteristic of FTLD and a posterior parietal (and temporal parietal) hypoperfusion characteristic of patients with dAD. CONCLUSIONS: These scintigraphic findings provide further support to the hypothesis that FTLD is not a mere stage but a distinct anatomoclinical form of AD. The combination of neuropsychological tests and [(99m)Tc]-HMPAO SPECT may be very useful in identifying patients with FTLD from the wider group of patients with dAD. This issue is particularly worthwhile, as there is increasing evidence that patients with FTLD have a slower rate of cognitive decline.  相似文献   
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Is apoptosis a diagnostic marker of acute myocardial infarction?   总被引:1,自引:0,他引:1  
OBJECTIVE: To investigate and quantify the presence of apoptosis in early myocardial ischemia in humans. METHODS: Histologic sections from the left and right ventricles of 16 hearts with impending myocardial infarction were stained with terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick end labeling (TUNEL) method and with antibodies to p53, bcl-2, cpp32, FAS, FAS-L, and bax. DNA electrophoretic analysis was also performed. RESULTS: According to the inclusion criteria, all 16 cases showed morphologic changes consistent with ischemia and/or reperfusion. TUNEL results were positive in 14 of the 16 ischemic areas. Unexpectedly, they were also positive in "remote from ischemia" myocardium of both the left and right ventricles. DNA electrophoretic analysis confirmed the results of TUNEL. Immunohistochemistry was uniformly negative, probably because of autolysis phenomena. CONCLUSIONS: We showed that apoptosis precedes necrosis in humans, but the detection of apoptosis cannot be used as a diagnostic tool, since it can also be triggered by nonischemic events.  相似文献   
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BACKGROUND: Leukapheresis for peripheral blood stem cell collection is increasingly being carried out in pediatric cancer patients. Aim of this study was to report experience of the Padua Apheresis Unit on a series of children weighting < 15 kg who have undergone such an apheresis procedure. METHODS: This retrospective study includes 15 pediatric patients affected with various malignancies (neuroblastoma: 7; acute myelogenous leukemia: 3; rhabdomyosarcoma: 2; PNET: 1; retinoblastoma: 1; Burkitt's lymphoma: 1) collecting peripheral blood stem cells by a Cobe Spectra blood cell separator. Main procedure parameters, including vascular access, leukapheresis duration, blood flow rate, processed blood volumes, side effects, mononuclear and CD34+ cell yields, have been registered. RESULTS: Altogether 22 sessions have been carried out, by processing a mean of 2.8 blood volumes. No leukapheresis related complications have been recorded, such as hypotension, hypocalcemia and hypothermia. Noteworthy, in 4 procedures two or more peripheral venipunctures have been performed to ensure an adequate blood flow. CONCLUSIONS: Leukapheresis for peripheral blood stem cell collection can be safely and efficaciously carried out in pediatric patients, even weighing < 15 kg, on the condition that certain aspects of apheresis practice in children (vascular access, volume shifts, anticoagulation, side effects) are carefully considered.  相似文献   
225.
Objective : Understanding patients' and their parents' perceptions towards asthma medication is important in developing strategies to ensure patient compliance. In this study, parents' perceptions towards their children's use of inhaled medication for asthma treatment were evaluated.
Methodology : A questionnaire was administered by interviewing parents of 210 asthmatic children attending the Department of Paediatrics, National University Hospital.
Results : Our results showed that 76/210 (36%) of parents either felt opposed to inhaler therapy and/or preferred oral medications. The main reasons for their reluctance to use inhalers were related to fear of dependence, side effects and overdosage, and the child's dislike for inhalers. A third of these parents felt that inhalers were only indicated for very severe asthma.
Conclusions : We conclude that a significant proportion of parents have reservations regarding the use of inhalers for the treatment of asthma. These factors should be taken into consideration when planning an effective asthma education programme.  相似文献   
226.
Objective : To assess the relationship between the subtypes of hypertension in pregnancy and subsequent neonatal haematology.
Methodology : Retrospective review of the haematology of newborns of hypertensive mothers at a tertiary neonatal unit
Results : Over a 2 year period. 249 infants had full blood examinations. Nineteen (7.6%) were neutropenic and 35 (14.1%) thrombocytopenic, including 11 (4.4%) who were both neutropenic and thrombocytopenic. Neutropenia occurred only in infants whose mothers had severe pre-eclampsia and eclampsia or pre-eclampsia with pre-existing hypertension, whereas thrombocytopenia complicated all maternal hypertension subtypes. Two (10%) of the neutropenic infants developed nosocomial infection while seven (20%) of the thrombocytopenic infants bled. Thirteen (68%) of the neutropenic infants compared with 15 (43%) of the thrombocytopenic infants developed their haematological abnormality within 24 h of birth. All but two infants developed the haematological abnormality by the 5th day of life.
Conclusions : Although haematological abnormalities in infants born to hypertensive mothers are uncommon, serious neonatal complications can occur and therefore early haematological screening of these infants is recommended.  相似文献   
227.
Nasopharyngeal carcinoma (NPC) is an endemic cancer in southern China and northern Africa, and its pathogenesis is not yet well defined at the molecular level. Although the involvement of p53 and of the retinoblastoma gene (RB/p105) in NPC has been well studied, there is paucity of mutational data regarding the retinoblastoma-related gene RB2/p130 in primary tumors and particularly in NPC. We have shown previously that RB2/p130 could be rearranged in a nasopharyngeal cell line. In the present study, we screened by single-strand conformation polymorphism and sequence analysis the retinoblastoma-related gene RB2/p130 for mutations within exons 19-22. Mutations in the RB2/p130 gene were detected in 3 of 10 primary human NPCs from Northern Africa (30%). These findings, along with previous data showing that genetic replacement of RB2/p130 restores a normal growth pathway in the nasopharyngeal cell line Hone-1, strengthen the hypothesis that genetic changes of RB2/p130 may be involved in the development and/or progression of nasopharyngeal cancer and suggest that RB2/p130 could be considered a tumor suppressor gene and may be a candidate for novel gene therapeutic approaches for NPC.  相似文献   
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