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761.
762.
Aims:  To determine the role of Na+/H+ exchanger regulatory factor ( NHERF1 ) in breast cancerogenesis and progression.
Methods and results:  NHERF1 expression was examined in normal tissue, ductal carcinoma in situ (DCIS), invasive carcinoma (IBC), synchronous metastatic lymph node and metachronous distant metastases of a retrospective series of breast cancers. Fifty-one IBC, 42 DCIS and normal tissues were examined immunohistochemically, and the colocalization between NHERF1 and HER2/neu was studied by immunofluorescence. NHERF1 showed a different localization and pattern of expression in the different compartments of the breast. The mean value of cytoplasmic NHERF1 expression in paired samples was significantly higher in DCIS, IBC, distant metastases and metastatic lymph nodes with respect to normal tissues. Moreover, in metastatic lymph nodes NHERF1 was exclusively cytoplasmic. In the membrane NHERF1 was colocalized with overexpressed HER2/neu in DCIS, IBC and distant metastases.
Conclusions:  Breast cancerogenesis is characterized by increased cytoplasmic expression of NHERF1 as the tumour progresses, suggesting a role in this process. The switch from apical membranous to cytoplasmic expression is compatible with a dual role for NHERF1 as a tumour suppressor or tumour promoter dependent on its subcellular localization.  相似文献   
763.
The purpose of this study was to investigate the self-perceived dental care needs and dental experiences of patients with angioedema. At the 1998 annual meeting of the Voluntary Association for the Fight, Study and Treatment of Hereditary Angioedema ("Associazione volontaria per la lotta, lo studio e la terapia dell'angioedema ereditario"), a self-administered questionnaire was distributed to participants affected by hereditary or acquired angioedema. Fifty-seven persons completed the questionnaire (37 females, 20 males; mean age, 39 ± 17 yrs; range, 5–76). The vast majority (91%) had the hereditary form of the disease. One-third of the respondents had some problems in obtaining oral treatment, with one person having been refused care. About half of the group had experienced an acute attack following dental treatment. Preventive measures needed improvement in about two-thirds of respondents. More than half (58%) of the group perceived a need for dental care. We conclude that persons with angioedema may experience difficulty in obtaining dental treatment, a common cause of acute attacks.  相似文献   
764.
Title.  Career trajectories of nurses leaving the hospital sector in Ontario, Canada (1993–2004).
Aim.  This paper is a report of an analysis of the career trajectories of nurses 1 year after leaving hospitals.
Background.  Although hospitals are traditionally the largest employers of nurses, technological advances and budgetary constraints have resulted in many countries in relative shrinkage of the hospital sector and a shift of care (and jobs) into home/community settings. It has been often assumed that nurses displaced from hospitals will move to work in the other workplaces, especially the community sector.
Method.  Employment patterns were tracked by examining a longitudinal database of all 201,463 nurses registered with the College of Nurses Ontario (Canada) between 1993 and 2004. Focusing on the employment categories Active (Working in nursing), Eligible-Seeking nursing employment or Dropout from the nursing labour market, year-to-year transition matrixes were generated by sector and sub-sector of employment, nurse type, age group and work status.
Findings.  For every nurse practising nursing in any non-hospital job or in the community a year after leaving hospitals, an average of 1·3 and four nurses, respectively, dropped out of Ontario's labour market. The proportion of nurses leaving hospitals transitioning to the Dropout category ranged from 63·3% (1994–95) to 38·6% (2001–02). The proportion dropping out of Ontario's market was higher for Registered Practical Nurses (compared to Registered Nurses), increased with age and decreased with degree of casualization in nurses' jobs.
Conclusion.  Downsizing hospitals without attention to the potentially negative impact on the nursing workforce can lead to retention difficulties and adversely affects the overall supply of nurses.  相似文献   
765.
The indigenous population of Australia constitutes approximately 2 per cent of the total population. This group has faced significant cultural, economic and health changes since European settlement some 200 years ago. In this brief review some of the health changes that have influenced the oral health status of this community have been examined. Of major importance is the dietary change that the once nomadic indigenous community has undergone. Today's Western diet, high in sugar, low in proteins and vitamins, has resulted in a significant increase in the risk (and prevalence) of caries and periodontal disease. In addition, the high prevalence of diabetes also exacerbates the periodontal problem. The remoteness of a significant proportion of Australian indigenous communities from modern health care services and limited access to fluoridation increases the incidence of oral disease. It is also noted that the incidence of rheumatic heart disease is one of the highest in the world, thereby increasing the risk of bacterial endocarditis. It is clear that indigenous communities have unique oral health needs but the extent of these needs is not well documented. It is important that more research be undertaken to assess these needs so that appropriate oral health programmes can be developed.  相似文献   
766.
Introduction:  Increased daytime blood pressure and reduced nocturnal dipping can already be found in children with type 1 diabetes mellitus. We hypothesized that impaired baroreflex sensitivity can cause this abnormal blood pressure behavior in children and adolescents with type 1 diabetes, reflecting an early stage of diabetic autonomic neuropathy.
Methods:  In the present study, we monitored beat-to-beat blood pressure and pulse interval non-invasively with portapres© in 38 patients with type 1 diabetes (7–18 yr) and 14 non-diabetic subjects (5–17 yr). The Trigonometric Regressive Spectral Analysis was used to assign spontaneous oscillations of blood pressure and pulse interval to defined frequency bands between 0.003 and 1.0 Hz and to calculate baroreflex sensitivity. Correlations with diabetes-specific data like hemoglobin A1c (HbA1c) and with 24-h blood pressure measurements were calculated.
Results:  The diabetic subjects displayed significantly less variance of blood pressure and pulse interval in the high frequency (HF) bands and a lower BRS. BRS decreased with higher HbA1c and daily insulin dose. We also saw significant changes in spectral variance of blood pressure and pulse interval with these parameters. Patients with higher sympathetic activity (LF/HF-ratio) during daytime measurements displayed more nocturnal dipping.
Conclusion:  Our data evidence impaired baroreflex sensitivity in children and adolescents with type 1 diabetes mellitus. We suggest spectral analysis of spontaneous blood pressure and pulse interval oscillations during night sleep to further pursue the role of baroreflex sensitivity in the etiology of the non-dipping phenomenon in diabetic patients.  相似文献   
767.
768.
Background: Supraventricular tachycardia (SVT) is often described as a recurrent condition that leads to emergency department (ED) visits. However, the epidemiology of ED visits for SVT is unknown.
Objectives: To define the frequency of SVT in U.S. EDs and to analyze patient characteristics, ED management, and disposition for such visits.
Methods: The authors analyzed data from the National Hospital Ambulatory Medical Care Survey, 1993–2003. SVT cases were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification codes 426.7 or 427.0 in any of the three diagnostic fields.
Results: Of the 1.1 billion ED visits over the 11-year study period, an estimated 555,000 (0.05%; 95% confidence interval [CI] = 0.04% to 0.06%) were related to SVT. The annual frequency and population rate appear stable between 1993 and 2003 (p for trend = 0.35). Compared with non-SVT visits, those with SVT were more likely to be older than 65 years of age (26% vs. 15%, p < 0.01) and female (70% vs. 53%, p < 0.01). Electrocardiograms were documented for most visits (91%; 95% CI = 85% to 96%). Approximately half of the patients (51%; 95% CI = 40% to 61%) received an atrioventricular nodal blocking medication, most frequently adenosine (26%; 95% CI = 17% to 36%). SVT visits ended in hospital admission for 24% (95% CI = 15% to 34%). At the other extreme, 44% (95% CI = 32% to 56%) were discharged without planned follow-up.
Conclusions: Supraventricular tachycardia accounts for approximately 50,000 ED visits each year. Higher visit rates in older adults and female patients are consistent with prior studies of SVT in the general population. This study provides an epidemiologic foundation that will enable future research to assess and improve clinical management strategies of SVT in the ED.  相似文献   
769.
This study examined the effect of stable transfection of latent transforming growth factor-beta1 (TGF-beta1) cDNA into a predominantly polygonal, 4 nitroquinoline N-oxide (4NQO)-induced rat oral keratinocyte cell line. Seven polygonal and five spindle clonal populations were isolated that overexpressed TGF-beta1 protein by approximately two- to four-fold compared to vector-only transfected controls. Neutralisation experiments indicated that the majority of protein was in the latent form. There was no change in the proportion of polygonal and spindle cells in vitro after transfection with TGF-beta1 cDNA. Polygonal and spindle cells that overexpressed TGF-beta1 produced similar amounts of protein and grew more slowly in vitro than controls. The parent cell line and all transfected cells were growth inhibited (60-75%) by exogenous TGF-beta1. Orthotopic transplantation of the parent and the vector-only control cell lines resulted in primary tumours in the floor of the mouth in almost 100% (20/21) of athymic mice, with no evidence of bone resorption at the site of the primary tumour and pulmonary metastatic tumour deposits in some 40% (7/20) of these animals. The polygonal and spindle cells that overexpressed TGF-beta1 behaved similarly following orthotopic transplantation. A 96% (23/24) primary tumour take was evident following transplantation of cells that overexpressed TGF-beta1, with a significantly (P<0.02) higher number of animals showing bone resorption at the site of the primary tumour (35%; 8/23) compared to controls. By contrast, there was a significant (P<0.03) decrease in the number of animals with pulmonary metastases (4%; 1/23) following transplantation of TGF-beta1 overexpressing cells compared to controls. Overexpression of TGF-beta1 did not alter tumour cell differentiation in vivo. The results demonstrate that endogenous TGF-beta1 functions as a tumour suppressor in the rat-4NQO model of oral carcinogenesis without altering tumour cell morphology or differentiation but can also act to promote local bone resorption.  相似文献   
770.
Emergency physicians are required to care for unstable patients with life-threatening conditions, and thus must make decisions that are both quick and precise about unclear clinical situations. There is increasing consensus in favor of using ultrasound as a real-time bedside clinical tool for clinicians in emergency settings alongside the irreplaceable use of historical and physical examinations. B-mode sonography is an old technology that was first proposed for medical applications more than 50 years ago. Its application in the diagnosis of thoracic diseases has always been considered limited, due to the presence of air in the lung and the presence of the bones of the thoracic cage, which prevent the progression of the ultrasound beam. However, the close relationship between air and water in the lungs causes a variety of artifacts on ultrasounds. At the bedside, thoracic ultrasound is based primarily on the analysis of these artifacts, with the aim of improving accuracy and safety in the diagnosis and therapy of the various varieties of pulmonary pathologic diseases which are predominantly “water-rich” or “air-rich”. The indications, contraindications, advantages, disadvantages, and techniques of thoracic ultrasound and its related procedures are analyzed in the present review.  相似文献   
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