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151.
Senile plaques in Alzheimer's disease (AD) are composed principally of Aβ, a 4 kDa fragment of the amyloid precursor protein (APP). Longer forms of APP which contain a Kunitz proteinase inhibitor (KPI) domain are elevated in aged and in AD brains. Tissue factor pathway inhibitor-1 (TFPI) contains three tandem KPI domains and has been well characterized for its role as a natural anticoagulant in the extrinsic coagulation pathway. Functionally, the first two KPI domains of TFPI bind and inhibit the activity of factor Xa and VIIa respectively. In addition, TFPI and APP-KPI share a common clearance mechanism through the low density lipoprotein receptor-related protein (LRP). As part of an ongoing study of the role of KPI-containing proteins in AD, the current study examines TFPI localization in the brain. We report here that TFPI is immunohistochemically localized to microglia in both AD and non-AD individuals and is localized to some senile plaques in AD. Western blot analyses indicate that the amount of TFPI is elevated in frontal cortex samples from AD brains. We propose that TFPI may play a cell specific role in proteinase regulation in the brain.  相似文献   
152.
Interobserver variability in neonatal cranial ultrasonography   总被引:1,自引:0,他引:1  
The reliability of cranial ultrasound diagnosis in the premature neonate was examined using data from an ongoing multicentre study of the epidemiology and long-term consequences of neonatal brain haemorrhage. First week ultrasound films (obtained at 4 hours, 24 hours and 7 days) from 60 study subjects were randomly selected for independent review by two groups of experienced interpreters, and results were recorded separately for observations (i.e. presence or absence of an abnormal echodense area on a film) and interpretations (i.e. presence or absence of haemorrhage or ventricular dilatation) in each hemisphere. Because of deaths in the first week of life, the total number of films examined was 138. Concordance on the presence or absence of an abnormal echodensity was examined for each individual film for three areas of interest: the germinal matrix, the ventricles and the parenchyma. Concordance on the presence or absence of haemorrhage or ventricular dilatation was examined only for the seventh-day film, or the final film prior to death. Finally, concordance was analysed with the diagnostic interpretations grouped into categories thought to differ prognostically for long-term outcome. In general, concordance was poorest for germinal matrix lesions and best for parenchymal lesions. Concordance was lower for observations made on each individual film than it was for interpretation of the final film in each case. Fifty-five of 60 cases (92%) were assigned to the same major prognostic category by both readers. Ultrasound review conferences were held periodically and there was evidence that concordance in ultrasound reading and interpretation improved during the course of the study.  相似文献   
153.
In 61 patients echographically examined in A and AB mode at Münster University Eye Hospital a membrane-like echo was found between the retina and the choroid. The acoustic characteristics were studied. The usefulness for the differential diagnosis of retinal detachment was demonstrated with several situations of the retina. The thickness of the retina and choroid can be measured in routine examinations.  相似文献   
154.
155.
Composite resin has proven to be a predictable and reliable restorative material for the treatment of traumatized dentin or dental caries in the anterior region. Ongoing material advancements continue to contribute to favorable results in the treatment of the contemporary patient. In using a resin material, it is important for the dental professional to establish an appropriate clinical approach that will protect healthy tissues, while meeting the patient's expectations. This article presents a series of cases that encompass the clinical and aesthetic possibilities provided by modern composites. LEARNING OBJECTIVES: This article depicts the potential clinical and aesthetic results that can be achieved using contemporary composite resins. Upon reading this article, the reader should: 1) Understand operative techniques for obtaining aesthetic results in the anterior maxilla. 2) Become familiar with the importance of formulating a treatment strategy that combines minimum chairtime with a high-quality, aesthetic result.  相似文献   
156.
OBJECTIVE: Breast-feeding is associated with better child development outcomes, but uncertainty remains primarily due to the close relationship between breast-feeding and socioeconomic status. This study assesses the issue in a low socioeconomic status sample where breast-feeding was close to universal. METHODS: Seven hundred eighty-four Chilean children were followed longitudinally from infancy. All but four were initially breastfed, 40% nursed beyond 12 months, and infant growth was normal. Child development was assessed at 5(1/2) years by a cognitive, language, and motor test battery. The duration of breast-feeding as the sole milk source was analyzed as a continuous variable, adjusting for a comprehensive set of background factors. RESULTS: The relationship between breast-feeding and most 5(1/2)-year developmental outcomes was nonlinear, with poorer outcome for periods of breast-feeding as the sole milk source for <2 months or >8 months--statistically significant for language, motor, and one comprehensive cognitive test, with a suggestive trend for IQ. CONCLUSIONS: The observed nonlinear relationships showed that breast-feeding as the sole milk source for <2 months or >8 months, compared with 2-8 months, was associated with poorer development in this sample. The latter finding requires replication in other samples where long breast-feeding is common and socioeconomic status is relatively homogeneous.  相似文献   
157.
158.
Objectives. We sought to examine the relation between regional changes in intramyocardial function and global left ventricular (LV) remodeling in the first 8 weeks after reperfused first anterior myocardial infarction (MI).

Background. Because of limitations in imaging methods used to date, this relation has not been thoroughly evaluated.

Methods. We studied 26 patients (21 men, 5 women; mean age 51 years) by magnetic resonance imaging (MRI) on day 5 ± 2 (mean ± SD) and week 8 ± 1 after their first anterior MI. All patients had single-vessel left anterior descending coronary artery disease and although they had received reperfusion therapy, all had regional LV dysfunction and an initial ejection fraction (EF) ≤50%. Short-axis magnetic resonance tagging was performed spanning the LV. Percent intramyocardial circumferential shortening (%S) on a topographic basis, LV mass index, LV end-diastolic volume index (LVEDVI), LV end-systolic volume index and LV ejection fraction (LVEF) were measured.

Results. Left ventricular mass index tended to decrease, whereas the LVEDVI increased from 82 ± 24 to 96 ± 27 ml/m2 (p = 0.002). Left ventricular end-systolic volume index remained unchanged, whereas LVEF increased from 39 ± 12% to 45 ± 14% (p = 0.002). Apical %S improved from 9 ± 6% to 13 ± 5% (p < 0.0001), as it did in the midanterior (6 ± 6% to 10 ± 7%, p < 0.02) and midseptal regions (8 ± 7% to 12 ± 6%, p < 0.02). Early dysfunction in remote midinferior and basal lateral regions resolved by 8 weeks. By multivariate analysis, the only significant predictor of an increase in LVEDVI over the study period was peak creatine kinase (p = 0.04).

Conclusions. In the first 8 weeks after a large, reperfused anterior MI, %S improved in the apex, midanterior and midseptal regions and normalized in remote noninfarct-related regions, but LV end-diastolic volumes also increased. This increased LVEDVI correlated with infarct size by peak creatine kinase and was not related to changes in global and regional LV function.  相似文献   

159.
We report a case of refractory bladder fistula in a diabetic renal allograft recipient that recurred shortly after conventional operative repair without any detectable external cause. After reoperation and use of a vascularized rectus muscle flap the fistula closed and the patient has retained excellent graft function. It is suggested that this technique should be considered as the primary repair modality for bladder fistulas in diabetic recipients, when wound healing is impaired seriously as a consequence of the combined effects of diabetic microangiopathy and steroid therapy.  相似文献   
160.
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