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61.
Hypertension complicates 6-8% of pregnancies and includes the following four conditions: hypertension preceding pregnancy or documented before the 20th week of gestation; pre-eclampsia (PE) / eclampsia; chronic hypertension with superimposed pre-eclampsia; and gestational hypertension. The latter is defined as a significant rise in blood pressure after the 20th week of pregnancy in previously normotensive women, to over 140/90 mmHg. When blood pressure remains above 160/110 mmHg, it is considered severe. PE is defined as the presence of proteinuria (≥300 mg/24 h) in pregnant women with hypertension. The hypertensive syndromes of pregnancy are among the leading causes of maternal and fetal morbidity and mortality and anti-hypertensive treatment is part of the therapeutic arsenal used to prevent serious complications. Although the role of utero-placental insufficiency due to deficient migration of trophoblasts to the spiral arteries is universally accepted, the pathophysiology of PE remains largely unknown and is the subject of debate. No effective ways of predicting or preventing PE have been found, which highlights the need for further research in this field. This review aims primarily to evaluate recent advances in our understanding of the pathophysiology of gestational hypertension and especially PE, and new ways of predicting PE. Additionally, we present a brief review on the diagnosis, prevention and treatment of PE.  相似文献   
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The calcium paradox was first mentioned in 1966 by Zimmerman et al. Thereafter gained great interest from the scientific community due to the fact of the absence of calcium ions in heart muscle cells produce damage similar to ischemia-reperfusion. Although not all known mechanisms involved in cellular injury in the calcium paradox intercellular connection maintained only by nexus seems to have a key role in cellular fragmentation. The addition of small concentrations of calcium, calcium channel blockers, and hyponatraemia hypothermia are important to prevent any cellular damage during reperfusion solutions with physiological concentration of calcium.  相似文献   
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The benign peripheral nerve sheath tumours are rare lesions mainly represented by schwannoma and neurofibroma. The present work evaluated the clinical and histopathological features of schwannomas and neurofibromas of the oral cavity diagnosed in a Brazilian population. Among 9.000 cases of oral lesions archived from 1970 to 2008, four schwannomas and 12 neurofibromas were identified, microscopically revised and immunohistochemically certified through a panel including monoclonal antibodies (anti-S100, vimentin, HHF-35 and desmin). From biopsy and histological sections records, clinical and histopathological data were retrieved, reviewed and statistically analysed. Predominantly, schwannomas affected non-white males (3:1), with an age and size averages of 34.7 years and 2.8 cm, respectively. Neurofibromas preferentially occurred on the gingival/alveolar ridge of white females (5:1), with 35.7-year mean age, peak of incidence between 3rd and 5th decade, and size average of 1.7 cm. (12 cases, 75%). The studied tumours exhibited more frequently as a painless, sessile and slow growth very similar to other oral lesions, but their microscopic features differed significantly. Schwannomas and neurofibromas are extremely uncommon in the oral cavity, exhibiting clinical features very similar but specific and peculiar microscopic findings that are useful in the establishment of the diagnosis, which in some particular cases must be confirmed by immunohistochemistry.  相似文献   
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J Oral Pathol Med (2012) 41 : 47–53 Objective: The aim of this study was to investigate the presence of CD1a‐positive Langerhans cells and their relationship with E‐cadherin in minor salivary gland tumors. Methods: Twenty‐seven minor salivary gland tumors were investigated using immunohistochemistry for CD1a and E‐cadherin. Results: A significant difference regarding the mean density of CD1a‐positive Langerhans cells was observed between pleomorphic adenomas and malignant tumors studied (P = 0.001). No CD1a‐positive cells were detected in most cases (n = 5) of cystic adenoid carcinomas. CD1a‐positive cells were detected in one mucoepidermoid carcinoma case, and six low‐grade polymorphous adenocarcinomas cases. Comparison of the mean density of CD1a‐positive cells between the three malignant tumors showed no significant difference (P = 0.127). No significant difference was observed in the presence of E‐cadherin between tumors (P = 0.73), but it was detected in 24 cases. Conclusions: The lack of CD1a‐positive in malignant salivary gland tumors facilitates the neoplastic development and suggests that these cells might be useful as auxiliary diagnostic and prognostic tool in minor salivary gland tumors. Furthermore, it is suggested that E‐cadherin mediates cell adhesion in these tumors although we did not demonstrate significance.  相似文献   
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The aim of this study was to describe the epidemiological characteristics of emergencies caused by asthma and chronic obstructive pulmonary disease (COPD) at the Hospital Clínico Universitario of Valencia (Spain) and to analyze factors related to hospital admissions for the same causes. Emergency room medical records for 1993 to 1995 of patients older than 14 years of age were examined to identify those due to asthma or COPD, according to established protocol. Demographic variables were described, followed by Poisson regression analysis of time and seasonal factors affecting emergencies. Factors related to hospital admission were analyzed by logistic regression, taking into account age group, sex, place of residence, and the year, month, day and hour of emergency room arrival. Asthma patients amounted to 1% of emergencies, while COPD patients accounted for 2%. The admission rate for women with asthma was higher than for men (F/M ratio = 0.78), whereas the rate for men with COPD was higher than for women (F/M ratio = 3.14). The largest age groups with asthma emergencies included young people aged 15 to 24 years old and those over 60. Hospital admissions or transfers to other hospitals were ordered for 17.4% of asthma patients and 38.8% of COPD patients. Nearly a third of COPD patients and a fifth of asthma patients were readmitted within the ten days following the first emergency. Clear temporal patterns of COPD emergency were observed for month (most occurring in winter), day of the week (most on Monday) and hour of the day (most during daytime hours, with fewer at midday). The time patterns were less evident for asthma emergencies, although the likelihood of admission because of asthma varied by month and day of the week. Emergency room records may be useful for studying the patterns of respiratory disease presentation. Other possible uses are epidemiologic monitoring and evaluation of health care quality.  相似文献   
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BACKGROUND: The different diagnosis between hypertrophic cardiomyopathy and athlete's heart has important clinical implications. The assessment of long axis left ventricular function with tissue Doppler imaging in hypertrophic cardiomyopathy (showing systolic and diastolic dysfunction with heterogeneity and asynchrony), may be useful in the differentiation of these situations. AIM: To study, with tissue Doppler imaging, long axis left ventricular function in a population of athletes (rowers) and to compare it with a population of non-obstructive hypertrophic cardiomyopathy patients. METHODS: In 24 patients with non-obstructive hypertrophic cardiomyopathy and in 20 competitive rowers with similar age, blood pressure and heart rate, we analyzed mitral annulus motion with pulsed tissue Doppler imaging in the 4 sides of the annulus (septal, lateral, inferior, anterior), in apical views. In each wave (systolic, rapid filling and atrial contraction) we measured velocities, time intervals and velocity-time integrals, and calculated heterogeneity and asynchrony indices. Data were compared between the groups, between the different sides in each group ("parallel analysis") and with conventional indices of global function. RESULTS: Hypertrophic cardiomyopathy patients showed: systolic function: lower velocities and integrals, shorter ejection time and shorter systolic time. These abnormalities occurred even in annular sites contiguous to walls without hypertrophy. DIASTOLIC FUNCTION: Much lower rapid filling velocities and integrals, lower atrial contraction velocities and integrals, lower e/a, longer isovolumic relaxation time and time to peak rapid filling wave. These abnormalities occurred even in annular sites adjacent to walls without hypertrophy. In the athletes group, the e/a ratio was never < 1, in any annular site. In hypertrophic cardiomyopathy patients this ratio was < 1 in 27% of the sites. CONCLUSIONS: 1--Systolic and diastolic long axis left ventricular function is different in hypertrophic cardiomyopathy and in athletes, in all mitral annulus sides. 2--The presence of these abnormalities in annular sites contiguous to walls without hypertrophy suggests that this technique may be useful in the differential diagnosis between these groups, particularly in the "gray zone" of Maron.  相似文献   
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