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1.
Melatonin reduces oxidative stress and improves vascular function in pulmonary hypertensive newborn sheep
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Flavio Torres Alejandro González‐Candia Camilo Montt Germán Ebensperger Magdalena Chubretovic María Serón‐Ferré Roberto V. Reyes Aníbal J. Llanos Emilio A. Herrera 《Journal of pineal research》2015,58(3):362-373
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN. 相似文献
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Sarah L Barber 《International journal for quality in health care》2006,18(4):306-313
OBJECTIVE: To evaluate variations in prenatal care quality by public and private clinical settings and by household wealth. DESIGN: The study uses 2003 data detailing retrospective reports of 12 prenatal care procedures received that correspond to clinical guidelines. The 12 procedures are summed up, and prenatal care quality is described as the average procedures received by clinical setting, provider qualifications, and household wealth. SETTING: Low-income communities in 17 states in urban Mexico. PARTICIPANTS: A total of 1253 women of reproductive age who received prenatal care within 1 year of the survey. MAIN OUTCOME MEASURE: The mean of the 12 prenatal care procedures received, reported as unadjusted and adjusted for individual, household, and community characteristics. RESULTS: Women received significantly more procedures in public clinical settings [80.7, 95% confidence interval (CI) = 79.3-82.1; P < or = 0.05] compared with private (60.2, 95% CI = 57.8-62.7; P < or = 0.05). Within private clinical settings, an increase in household wealth is associated with an increase in procedures received. Care from medical doctors is associated with significantly more procedures (78.8, 95% CI = 77.5-80.1; P < or = 0.05) compared with non-medical doctors (50.3, 95% CI = 46.7-53.9; P < or = 0.05). These differences are independent of individual, household, and community characteristics that affect health-seeking behavior. CONCLUSIONS: Significant differences in prenatal care quality exist across clinical settings, provider qualifications, and household wealth in urban Mexico. Strategies to improve quality include quality reporting, training, accreditation, regulation, and franchising. 相似文献
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The morbidity and mortality conference (M&MC) appears to have sprung from the efforts of physicians to improve practice through the examination of medical errors and bad outcomes. The modern M&MC has had limited examination (and almost none outside surgery and anesthesia), but may be straying from the precepts from which it evolved. Learning from one's errors is important, but confronting them is difficult and is particularly delicate when done in conference. If the effort is successful, it can serve as a model. If unsuccessful, it can instead convey the lesson that attempting to learn from error is at best unproductive and at worst unpleasant. Thus, the M&MC is a double-edged sword, and particular attention should be given to the way that it is conducted. The authors review the historical roots and current literature on the M&MC, discusses relevant literature on medical error, and offers a definition, guiding principles, and a set of guidelines for a modern internal medicine M&MC. The ideas are presented not as a blueprint, but rather to stimulate a debate on the merits of establishing a framework for a working model, in order to refocus on the tradition of self-analysis and critical thinking in a manner that is productive for all participants. 相似文献
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C. R. Gálvez V. C. Fernández J. M. R. De Los Reyes M. M. M. Jaén & R. G. Teruel 《International journal of gynecological cancer》2004,14(5):1040-1044
Choriocarcinoma is one of the most serious forms of gestational trophoblastic tumor. It is a malignant tumor from the epithelium of the chorionic villi. The most frequent location site is the uterus. Associated with ectopic pregnancy, it is extremely rare and in general, very aggressive. In 75% of the cases, it items from distant metastasis; therefore, a histological examination of the tubes must be performed in all ectopic pregnancies. Our patient was a 33-year-old woman who was admitted to emergency room (ER) with an intense pain in the right, iliac cavity, and limited genital bleeding. During the exploration, there was abdominal pain, with doubtful signs of peritoneal irritation. The vaginal ultrasound offered an image that was compatible with an extra uterine pregnancy in the left appendages. At emergency, right salpingectomy was performed via laparotomy. The patient was treated with polychemotherapy and contraceptives for a year, with no recurrence of the disease. Control follow-up was performed using beta-human chorionic gonadotropin (HCG) testing on a weekly basis during the first month and then bi-monthly during the first year of follow-up. 相似文献
6.
Aneurisma de aorta abdominal infrarrenal en asociación con riñón en herradura: aportación de un caso
Nerea Senarriaga Ruiz de la Illa Reyes Vega Manrique Isabel Lacasa Viscasillas Iñaki Iriarte Soldevilla Miguel Unda Urzaiz 《Actas urologicas espa?olas》2009,33(10):1141-1144
We review the association between surgically resolvable aortic disease and horseshoe kidney with a discussion of diagnostic problems and therapeutic options.Male patient 81 years of age with horseshoe kidney and an abdominal aortic aneurysm that was discovered by chance in an abdominal ultrasound during a check-up for his prostate condition.A retroperitoneal approach was used in order to resect the aneurysm and perform an aorto-aortic bypass with no complications occurring. Two years after the diagnosis, the patient is still asymptomatic from a vascular point of view.The co-presence of horseshoe kidney and aortic disease needing surgical correction is infrequent, but it significantly increases the technical complexity of aortic reconstruction. A literature review is included. 相似文献
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N. R. Galloway J. Tolia C. Barber 《Documenta ophthalmologica. Advances in ophthalmology》1986,63(1):31-36
The pattern evoked electroretinogram (PERG) was investigated in 11 patients with unilateral optic nerve disease and in a series of age-matched controls. The visually evoked potential (VEP) was also measured. The PERG showed a similar reduction to the VEP in optic nerve disease. Serial studies indicate that the PERG may not be affected immediately in some instances but may show a gradual decline over several months. 相似文献
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LYMPHOGRANULOMA VENEREUM 总被引:3,自引:0,他引:3