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Non-obstetrical acute abdomen during pregnancy   总被引:7,自引:0,他引:7  
Acute abdomen in pregnancy remains one of the most challenging diagnostic and therapeutic dilemmas today. The incidence of acute abdomen during pregnancy is 1 in 500-635 pregnancies. Despite advancements in medical technology, preoperative diagnosis of acute abdominal conditions is still inaccurate. Laboratory parameters are not specific and often altered as a physiologic consequence of pregnancy. Use of laparoscopic procedures as diagnostic tools makes diagnosis of such conditions earlier, more accurate, and safer. Appendicitis is the most common cause of the acute abdomen during pregnancy, occurring with a usual frequency of 1 in 500-2000 pregnancies, which amounts to 25% of operative indications for non-obstetric surgery during pregnancy. Surgical treatment is indicated in most cases, as in nonpregnant women. Laparoscopic procedures in the treatment of acute abdomen in pregnancy proved safe and accurate, and in selected groups of patients are becoming the procedures of choice with a perspective for the widening of such indications with more frequent use and subsequent optimal results. Despite these advances, laparotomy still remains the procedure of choice in complicated and uncertain cases.  相似文献   
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The two components of the gastroesophagealbarrier, the sphincter and the crural sling, closelyoverlap in humans, whereas they are widely separated inthe rat. This investigation correlates the anatomical components of the barrier and their manometriccounterparts in this animal. Sphincteric and cruralsling pressures were measured in four quadrants in 23rats. Muscle thickness was measured at nine levels of the gastroesophageal junction in the samequadrants in 12 rats and the muscular architecture ofthe region was studied in 10 fresh specimens. Themanometric sphincteric component is stronger on theright side where the thickest muscle fibers anchor tothe anterior and posterior borders of a mucosal ridgethat almost surround the cardia. Conversely, the slingpressure is highest towards the left where the muscular bundles straddle the esophagus. Inconclusion, there is a close correspondence between themanometric image and the muscular architecture of thecomponents of the gastroesophageal barrier in the rat. The anatomical arrangement of U-shapedmuscular bundles oriented in opposite directions createsa particularly powerful antireflux mechanism.  相似文献   
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Heart Failure Reviews - Cardiac resynchronization therapy (CRT) may improve not only impaired left ventricular contractility but can also induce reverse remodeling of native conduction system....  相似文献   
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The renal resistive index (RRI) measured by Doppler sonography is a marker of microvascular status that can be generalized to the whole of the arterial tree. Its association with large‐vessel dysfunction, such as arterial stiffness or the atherosclerotic burden, can help to establish physiopathological associations between macrocirculation and microcirculation. The authors conducted a cross‐sectional study of hypertensive patients (n=202) and a healthy control group (n=16). Stiffness parameters, atherosclerotic burden, and determination of the RRI in both kidneys were performed. The average RRI was 0.69±0.08 and was significantly greater in patients with diabetes and chronic kidney disease. Renal resistive index positively correlated with age, creatinine, and albuminuria. Positive correlations were found with arterial stiffness parameters (pulse wave velocity, ambulatory arterial stiffness index, and 24‐hour pulse pressure), as well as atherosclerotic burden and endothelial dysfunction measured as asymmetric dimethylarginine in serum. In the multivariate analysis, independent factors for increased RRI were age, renal function, 24‐hour diastolic blood pressure, and arterial stiffness. The authors concluded that there is an independent association between renal hemodynamics and arterial stiffness. This, together with the atherosclerotic burden and endothelial dysfunction, suggests that there is a physiopathologic relationship between macrovascular and microvascular impairment.  相似文献   
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Cell replication integrates aberrations of cell cycle regulation and diverse upstream pathways which all can contribute to melanoma development and progression. In this study, cell cycle regulatory proteins were detected in situ in benign and malignant melanocytic tumors to allow correlation of major cell cycle fractions (G1, S-G2, and G2-M) with melanoma evolution. Dysplastic nevi expressed early cell cycle markers (cyclin D1 and cyclin-dependent kinase 2; Cdk2) significantly more (p?<?0.05) than common nevi. Post-G1 phase markers such as cyclin A, geminin, topoisomerase IIα (peaking at S-G2) and aurora kinase B (peaking at G2-M) were expressed in thin (≤1 mm) melanomas but not in dysplastic nevi, suggesting that dysplastic melanocytes engaged in the cell cycle do not complete replication and remain arrested in G1 phase. In malignant melanomas, the expression of general and post-G1 phase markers correlated well with each other implying negligible cell cycle arrest. Post-G1 phase markers and Ki67 but none of the early markers cyclin D1, Cdk2 or minichromosome maintenance protein 6 (Mcm6) were expressed significantly more often in thick (>1 mm) than in thin melanomas. Marker expression did not differ between metastatic melanomas and thick melanomas, with the exception of aurora kinase A of which the expression was higher in metastatic melanomas. Combined detection of cyclin A (post-G1 phase) with Mcm6 (replication licensing) and Ki67 correctly classified thin melanomas and dysplastic nevi in 95.9 % of the original samples and in 93.2 % of cross-validated grouped cases at 89.5 % sensitivity and 92.6 % specificity. Therefore, cell cycle phase marker detection can indicate malignancy in early melanocytic lesions and accelerated cell cycle progression during vertical melanoma growth.  相似文献   
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Heart failure is a common clinical condition associated with high morbidity and mortality rate despite significant improvements in pharmacotherapy and implementation of medical procedures. Patients with heart failure are at an increased risk of developing arterial and venous thrombosis, which contribute to the high rate of adverse events and fatal outcomes. Many heart failure patients routinely receive antithrombotic therapy due to the presence of a specific indication for its use, like ischemic heart disease or atrial fibrillation. However, there is no solid evidence to support the routine use of antithrombotic agents in all heart failure patients. This article reviews the evidence for using antithrombotic therapy in heart failure patients.Heart failure (HF) is a complex clinical syndrome caused by a number of different disorders that impair the heart muscle’s ability to maintain adequate blood flow to meet the body''s metabolic needs. Research and advances in managing HF so far have been mainly focused on improving the neurohormonal imbalance and assisting the myocardium to increase the cardiac output with different types of devices. Over the last couple of decades there have been considerable improvements in pharmacotherapy and medical procedures for treating HF, such as the introduction of angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), beta blockers, aldosterone antagonists, If channel blocker ivabradine, cardiac resynchronization therapy (CRT), and ventricular assist devices (VADs). However, HF is still a major public health issue associated with increased morbidity and mortality (1). Because of the broad spectrum of its clinical presentations, aging of the population, and different comorbidities and treatment options, HF treatment represents a considerable challenge. Patients with HF are at an increased risk of developing arterial and venous thrombosis, which contribute to the high rate of adverse events and fatal outcomes (2-5). Further research should clarify whether routine use of antithrombotic agents brings clinical benefit to all HF patients.  相似文献   
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