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71.
There are multiple causes of hepatitis. The most frequent etiologies are viral, usually hepatitis A, B and C viruses. However, other, non-hepatotropic viruses can cause this disease, including parvovirus B19. We present a case of acute hepatitis due to parvovirus B19, as well as a review of the epidemiological, clinical, diagnostic and therapeutic features of this entity.  相似文献   
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The extensive use of invasive procedures and of long-term norfloxacin prophylaxis in the management of cirrhotic patients may have influenced the epidemiology of bacterial infections in cirrhosis. We conducted a prospective evaluation of all bacterial infections diagnosed in patients with cirrhosis in a Liver Unit between April 1998 and April 2000. A total of 405 patients presented 572 bacterial infections in 507 admissions. Spontaneous bacterial peritonitis was the most frequent infection (138 cases). Gram-positive cocci were responsible for 53% of total bacterial infections in the study, being the main bacteria isolated in nosocomial infections (59%). Patients requiring treatment in an intensive care unit and those submitted to invasive procedures presented a higher rate of infections caused by gram-positive cocci (77% vs. 48%, P <.001 and 58% vs. 40%, P <.02, respectively). Fifty percent of culture-positive spontaneous bacterial peritonitis in patients on long-term norfloxacin administration (n = 93) and 16% in patients not receiving this therapy (n = 414) were caused by quinolone-resistant gram-negative bacilli, P =.01. The rate of culture-positive spontaneous bacterial peritonitis caused by trimethoprim-sulfamethoxazole-resistant gram-negative bacilli was also very high in patients on long-term norfloxacin administration (44% vs. 18%, P =.09). In conclusion, infections caused by gram-positive cocci have markedly increased in cirrhosis. This phenomenon may be related to the current high degree of instrumentation of cirrhotic patients. Quinolone-resistant spontaneous bacterial peritonitis constitutes an emergent problem in patients on long-term norfloxacin prophylaxis, with trimethoprim-sulfamethoxazole not being a valid alternative.  相似文献   
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In May 2003 the almost simultaneous publication of the Update on Clinical Practice Guidelines by The Spanish Society of Cardiology, an initial document of the VII Report of Joint National Committee (JNC), and the European Society of Cardiology and European Society of Hypertension Guidelines in another jointly issued document, created controversy. The points of disagreement basically concerned the classification of hypertension, the choice of treatment strategy on the basis of individual cardiovascular risk, and the choice of initial treatment. A detailed analysis of the three documents, however, reveals more points of concurrence than of actual disagreement. A category between normal blood pressure and established hypertension, classified as prehypertension in the VII JNC Report and as normal-high BP in the Spanish and European Society of Cardiology Guidelines, includes a population at high risk for developing hypertension and in which lifestyle modifications are needed. In some specific clinical situations, basically in vascular high-risk patients, there is broad consensus on the definition of therapeutic groups based on scientific evidence from large clinical trials. In patients not included in a group with a specific indication, any drug included in the 5 main therapeutic groups can be used as the first step in treatment; in this group of patients thiazide diuretics play a preponderant role. The main objective of hypertension treatment is to obtain maximal reduction in overall cardiovascular risk, which requires correction of all associated risk factors and appropriate treatment for target organs likely to be affected.  相似文献   
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Effect of oral glucose administration on ghrelin levels in obese children   总被引:7,自引:0,他引:7  
OBJECTIVE: Coexpression of GH secretagogue receptor and ghrelin in the pancreas suggests that this peptide is involved in glucose metabolism. Previous reports in adult humans have demonstrated that plasma ghrelin levels decrease after oral glucose administration. However, no data are available in children. Therefore, the aim of this study was to analyze the response of plasma ghrelin levels in obese children after oral glucose administration. SUBJECTS AND METHODS: Twenty-eight obese children ranging from Tanner I to Tanner V were studied. All subjects were given 0.75 g/kg (maximum 75 g) glucose solution after overnight fasting. Ghrelin, insulin, glucose and IGF-binding-protein-1 were determined at 0, 30, 60 and 120 min of the oral glucose tolerance test (OGTT). RESULTS: Basal plasma ghrelin levels were significantly lower than in the respective control groups. These levels decreased significantly during OGTT in obese children, reaching a nadir of 28+/-9% at 60 min in parallel with the maximum increase in glucose levels and previous to maximum insulin levels. CONCLUSION: The rapid fall in plasma ghrelin concentration in obese children after glucose load suggests a mechanism for the control of appetite after food intake.  相似文献   
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Previous studies have demonstrated a protective effect of the cyclin-dependent kinase (CDK) inhibitor p27Kip1 against atherosclerosis and restenosis, two disorders characterized by abundant proliferation and migration of vascular smooth muscle cells and adventitial fibroblasts. These therapeutic effects might result from p27Kip1-dependent suppression of both cell proliferation and migration. However, the interplay between cell growth and locomotion remains obscure. We show here that p27Kip1 inhibits cellular changes that normally occur during cell locomotion (eg, lamellipodia formation and reorganization of actin filaments and focal adhesions). Importantly, a p27Kip1 mutant lacking CDK inhibitory activity failed to inhibit vascular smooth muscle cell and fibroblast proliferation and migration. Moreover, a constitutively active mutant of the retinoblastoma protein (pRb) insensitive to CDK-dependent hyperphosphorylation inhibited both cell proliferation and migration. In contrast, inactivation of pRb by forced expression of the adenoviral oncogene E1A correlated with high proliferative and migratory activity. Collectively, these results suggest that cellular proliferation and migration are regulated in a coordinated manner by the p27Kip1/CDK/pRb pathway. These findings might have important implications for the development of novel therapeutic strategies targeting the fibroproliferative/migratory component of vascular occlusive disorders.  相似文献   
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INTRODUCTION: The causes of cardiac tamponade vary and it has been suggested that underlying causes should be sought in all cases. The purpose of this study was to determine the causes of cardiac tamponade in our environment, distinguishing between specific and idiopathic causes, and analyzing the proportion and causes in the subgroup of patients with relapsing tamponade. PATIENTS AND METHOD: We retrospectively studied all patients who underwent therapeutic pericardiocentesis between 1985 and 2001. The clinical and radiographic features and macroscopic characteristics of the pericardial fluid were analyzed. The final diagnosis in each patient was based on the clinical history, follow-up, pericardial fluid cytology, and pericardial biopsy, if available. RESULTS: Ninety-six patients were included (52 men/44 women), mean age 56.1 16.1 years. The cause of pericardial effusion was neoplasm in 50 patients (52.1%), 14 idiopathic pericarditis (14.6%), 12 renal failure (12.5%), 7 iatrogenic cases (7.3%), 4 mechanical tamponades (4.2%), 2 tuberculosis (2.1%), and 7 other causes (7.3%). Thirty-five patients had relapsing tamponade; only 2 of them had idiopathic pericarditis (5.7%). We found no significant differences in age, development time, extracted volume or fluid features between tamponade of specific or idiopathic origin. CONCLUSIONS: Most of the cardiac tamponades in our series had a specific cause. This made it necessary to identify a specific underlying cause in each case, especially in relapsing effusions. However, we did not find any variable suggestive of the cause of the disease.  相似文献   
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