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31.
Cyclin D1 in astrocytic tumours: an immunohistochemical study   总被引:1,自引:0,他引:1  
Forty-eight astrocytic tumours were stained immunohistochemically with antibodies to the cell cycle-regulating protein, cyclin D1, and to the proliferation marker MIB1 (Ki-67) using formalin fixed paraffin embedded tissue and a microwave antigen retrieval system. Cases were classified by the WHO system (1993). The labelling indices (LI) for both antibodies were compared with each other and with the tumour type. The mean labelling indices for both antibodies increased with the degree of malignancy, and a significant difference was seen between the pilocytic astrocytoma and diffuse astrocytoma together vs anaplastic astrocytoma and glioblastoma together. However, within each tumour type there was considerable variation in the labelling indices and a clear cut off value could not be demonstrated. There was a strong positive correlation between labelling indices for cyclin D1 and MIB1 in diffuse astrocytoma, but this correlation broke down increasingly in anaplastic astrocytoma and glioblastoma. There was poor correlation between cyclin D1 and MIB1 in pilocytic astrocytoma, a feature which appeared to separate them from the diffuse astrocytoma. Average labelling indices for cyclin D1 were higher than those of MIB1, which suggests that cyclin D1 positive cells represent a pool of cells from which proliferation and hence MIB1 expression can take place. In conclusion, cyclin D1 is overexpressed in astrocytic tumours, more so with increasing grade of malignancy and in a way which approximately correlates with MIB1 expression.  相似文献   
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BACKGROUND: Assessment of inpatient asthma management has generally been limited to urban settings, including Chicago, which is known for its high asthma morbidity and mortality. Previously published data have been based on survey methodology. The Suburban Asthma Consortium (SAC) sought to obtain patient-based data unique to the Chicago suburbs to improve asthma care in those areas. OBJECTIVE: To evaluate current inpatient asthma management based on the 1997 National Asthma Education and Prevention Program (NAEPP). DESIGN: Retrospective chart review of all hospitalized patients 3-65 years bearing asthma-related ICD-9 codes for fiscal year 2002 in community, nonteaching hospitals in Chicago suburbs. RESULTS: Nine hundred two cases were submitted from seven hospitals. The majority ( > or = 75%) received inhaled bronchodilators, systemic steroids, oxygen and pulse oximetry. Antibiotic use (67%), chest radiography (85%), complete blood count (77%), and electrolytes (59%) appeared excessive in view of NAEPP recommendations. Peak flow monitoring (PFM) was recorded on admission in 45% of patients 5 years old and older; 52% had PFM during hospitalization. Thirty-eight percent of patients were taking ICS prior to admission; of those not on ICS, only 12% were newly diagnosed asthmatics. Overall, 51% of patients were discharged with ICS. Patients were more likely to receive ICS at discharge if they had required intensive care (ICU), had been on ICS prior to admission, were referred to an asthma specialist while hospitalized, or were insured. Patients with Medicare/Medicaid (MC/MA) had more repeat emergency visits and hospitalizations, longer lengths of stay, and received less ICS at discharge. Depending on the parameter, 41% or less patients received discharge planning education and were not more likely to have received education if in the ICU. Results ranged significantly between hospitals for most parameters (p < 0.05 or less). CONCLUSION: Study subjects received appropriate acute therapy and oxygen monitoring, but there was a divergence from NAEPP recommendations regarding PFM, ICS use, antibiotics, and laboratory evaluation. Patients receiving MC/MA experienced higher morbidity and received less ICS. Discharge asthma education was suboptimal for most hospitals. Most parameters demonstrated significantly wide practice variations between hospitals. Peak flow monitoring and patient education findings differed significantly from those in survey-conducted studies.  相似文献   
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In recent years a growing body of evidence has implicated deficits in the automaticity of fundamental facts such as word and number recognition in a range of disorders: including attention deficit hyperactivity disorder, dyslexia, apraxia and autism. Variously described as habits, fluency, chunking and over learning, automatic processes are best understood in terms of their distinctive properties. While typically identified as fast, parallel, attention-free processes, a commonly agreed definition of automaticity continues to elude theorists investigating this concept. Most theorists would, however, agree that since attentional resources are finite, automaticity of basic facts serves to free sufficient mental resources for a learner to focus their attention on the novel or more complex aspects of a task. Yet despite the importance of automaticity to the learner, the term remains largely unfamiliar to most educationalists and early years practitioners. In order to address this issue, the present paper seeks to review several influential theories of automaticity, to describe the problems associated with defining a process as automatic and to draw from relevant research to demonstrate how the early years environment can be organised to promote automaticity in the young learner.  相似文献   
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The use of B-type natriuretic peptide to diagnose congestive heart failure.   总被引:2,自引:0,他引:2  
This paper explains the background and current use of B-type natriuretic peptide (BNP) assays to differentiate congestive heart failure (CHF) from other causes of dyspnea. With a large and growing elderly population, CHF is being diagnosed much more often in emergency rooms in the United States. Doctors need a way to quickly distinguish whether a patient with respiratory distress is suffering from cardiac insufficiency or another etiology. BNP is released from the ventricles in response cardiac overload from CHF or some other form of left ventricular systolic dysfunction. Therefore, the detection and measurement of BNP is a fast and accurate method of determining if CHF is the cause of a patient's breathing difficulties.  相似文献   
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