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71.
Computed tomography of abdominal fatty masses 总被引:2,自引:0,他引:2
72.
Vázquez E Creixell S Carreño JC Castellote A Figueras C Pumarola F Poch JM Lucaya J 《Current problems in diagnostic radiology》2004,33(3):127-145
Acute bacterial sinusitis is usually a clinical diagnosis. Orbital complications require emergent evaluation with computed tomography. Using the orbital septum as an anatomic landmark, such infections can be classified as pre- or postseptal and treated with the most adequate therapy, ie, oral or intravenous antibiotics or surgical endonasal drainage. Intracranial complications can be seen in 3.7% to 11% of these patients, often with subtle clinical symptoms and signs. Radiologists play a decisive role in the final management of these patients and should be familiar with the most relevant complications. In this article, we present a retrospective review of all pediatric patients referred to our department for paranasal sinuses and orbital computed tomography because of acute complicated bacterial sinusitis. They were studied with an emergent enhanced facial and cranial computed tomography within 24 hours of admission, followed by magnetic resonance imaging when intracranial complications were suspected. Particular emphasis is placed on the imaging algorithm and the most relevant complications; we correlate imaging findings with clinical and bacteriological data. 相似文献
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The treatment of the patient with chronic hepatitis B virus infection (HBV) must be carried out with the knowledge that the percentage of patients infected with the B virus that develop chronic hepatitis remains between 5-10%. Of these, 10-30% will present chronic infection with active viral replication, necroinflammatory hepatic lesion, evolution to hepatic cirrhosis and the risk of developing hepatocarcinoma. For this reason, the aim of treatment is to achieve negativisation of the HBeAg, seroconversion to anti-HBe and a reduction of viral replication to undetectable values (estimated by level of DNA-HBV), for protracted periods of time. When a sustained loss of HBeAg and a reduction of viral replication are obtained, a biochemical, clinical and histological remission is achieved. Up until now the therapeutic alternatives in chronic infection by the B virus have been immunomodulation with Interferon alpha and the blocking of viral replication with lamivudine or adefovir dipivoxil. A difference must be drawn between the biochemical response, defined as a fall in the transaminases to normal values, and the virological response, which refers to a fall in the levels of DNA-HBV below 10(5) copies/ml. Finally, the complete response is defined as the virological and biochemical response with negativisation of the HBsAg. If a sustained response is obtained for several months, a histological response can be predicted with reduction in the intensity of the hepatic lesion and an absence or stabilisation in the process of fibrosis. The sustained response should last for no less than 6 to 12 months following the end of treatment. 相似文献
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OBJECTIVE:
Inflammation plays an important role in the development of chronic lung disease (CLD), which has become a major cause of morbidity in surviving infants less than 1250 g at birth. The authors hypothesized that the progression of this inflammation and, therefore, the establishment of CLD would be decreased with the use of early prophylactic inhaled corticosteroids. Short, and long term respiratory and neurodevelopmental outcomes were also examined.DESIGN:
A double-blind, randomized placebo controlled trial.SETTING:
Level-III neonatal intensive care unit.POPULATION STUDIED:
Sixty infants less than 1250 g at birth, diagnosed with respiratory distress syndrome and requiring ventilatory support at 72 h of age were enrolled in the study.INTERVENTION:
Infants enrolled received either placebo or beclomethasone diproprionate by a metered dose inhaler, which was used in-line with the ventilator circuit while the infant was ventilated and then via a spacer until 28 days of age.RESULTS:
Thirty infants were given beclomethasone and 30 were given placebo. There were two deaths in each group. Among the surviving infants, the frequency of moderate-to-severe CLD was 17% in each study group. Mean time to extubation was not different for beclomethasone compared with placebo at 16.4 and 12.5 days (P=0.12), respectively. The requirement for intravenous corticosteroids was lower in the beclomethasone-treated group (RR 0.67, 95% CI 0.43 to 1.04), although this difference was not statistically significant. The incidence of growth failure, infection and intraventricular hemmorhage did not differ between the two groups. Long term outcomes were not different with respect to the incidence of respiratory re-admissions, cerebral palsy, developmental delay, blindness or deafness.CONCLUSIONS:
Early treatment with inhaled beclomethasone diproprionate did not reduce the incidence of CLD or decrease the duration of mechanical ventilation. The decrease in intravenous corticosteroid use was not statistically significant. Long term outcome was not affected. 相似文献77.
Mariscal LF López-Alcorocho JM Rodríguez-Iñigo E Ortiz-Movilla N de Lucas S Bartolomé J Carreño V 《Virology》2002,301(1):121-129
TT virus (TTV) is an unenveloped, single-stranded, circular-DNA virus which resembles members of the Circoviridae, that is commonly found in humans and which lacks pathological consequences for the infected host. TTV replication has been demonstrated in bone marrow cells but not in peripheral blood mononuclear cells (PBMC), suggesting that hematopoietic cells must be activated to support TTV replication. To test this hypothesis, PBMC from two naturally TTV-infected individuals and from two healthy TTV-DNA negative donors infected in vitro with a TTV-DNA-positive serum were cultured in the presence (stimulated) or absence (unstimulated) of phytohemagglutinin, lipopolysaccharide, and interleukin-2. TTV-DNA was detected in both stimulated and unstimulated PBMC. However, TTV-DNA replicative intermediates and mRNA were detected only in stimulated PBMC. Furthermore, TTV-DNA and mRNA were detected in PBMC from two TTV negative donors reinfected with supernatants from TTV-infected stimulated cells but not when using culture supernatants from unstimulated cells. These results demonstrate that TTV replicates in PBMC only when stimulated. 相似文献
78.
Hepatitis C virus core protein transactivates the inducible nitric oxide synthase promoter via NF-kappaB activation 总被引:5,自引:0,他引:5
Intrahepatic levels of the inducible nitric oxide synthase (iNOS) are increased in chronic hepatitis C patients. As iNOS gene promoter contains Nuclear Factor (NF)-kappaB binding sites and hepatitis C virus (HCV) core protein activates NF-kappaB, the aim of this work was to study if HCV core protein transactivates iNOS promoter through NF-kappaB activation. iNOS mRNA and protein were determined by RT-PCR and western blot in HepG2 cells. The effect of HCV core protein on iNOS promoter was assayed by cotransfecting HepG2 cells with the core protein expression plasmid pHCV-Co and p1iNOS-CAT or p2iNOS-CAT plasmids. Formation of NF-kappaB-DNA complexes was determined by electrophoretic mobility shift assay. Transfection of HepG2 cells with pHCV-Co plasmid results in an increase in iNOS mRNA and protein levels. Cotransfection with pHCV-Co and p1iNOS-CAT or p2iNOS-CAT plasmids results in a transactivation of iNOS promoter, the presence of the proximal NF-kappaB binding site in the promoter being sufficient for the transactivation. Furthermore, the HCV core protein increases the formation of complexes between NF-kappaB and its binding sequence in the iNOS promoter. The expression of the NF-kappaB inhibitor IKB reverts the effect of the HCV core protein on the iNOS promoter. In conclusion, HCV core protein transactivates iNOS gene promoter through NF-kappaB activation. 相似文献
79.
Ventral hernia repair: a study of current practice 总被引:5,自引:5,他引:0
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study
was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were
gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair
was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of
repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia
size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias.
Clinical trials are required to establish the best method of repair for this common condition.
Electronic Publication 相似文献
80.