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1.
The laryngeal mask in failed intubation   总被引:1,自引:0,他引:1  
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Truncus Arteriosus With Patent Ductus Arteriosus and Normal Aortic Arch   总被引:1,自引:0,他引:1  
In hearts with a common arterial trunk (truncus arteriosus), there is almost always an inverse development of the aortic arch and the ductus arteriosus. Truncus with a normal aortic arch and a patent ductus is a rare echocardiographic and surgical finding. In this report, we describe 2 neonates in whom truncus arteriosus with a normal aortic arch and a medium or large patent ductus was diagnosed by preoperative echocardiography (without catheterization) and confirmed intraoperatively.  相似文献   
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BACKGROUND: Elevated liver enzymes are infrequent in patients with hepatitis C virus (HCV) infection undergoing chronic hemodialysis (HD), suggesting that the alanine aminotransferase (ALT) is a poor predictor of hepatocellular damage in this population. OBJECTIVE: To establish a more appropriate cut-off value of ALT to identify biochemical activity due to HCV infection in HD patients. STUDY DESIGN: A total of 217 patients, with an average age of 51.2 years, were evaluated between January and October 2002; 130 were males (60%). Serum ALT was measured by a kinetic method in five consecutive monthly blood samples, from which an average was obtained and divided by the upper limit of normal (ULN). HCV antibodies were determined using an enzyme immunoassay, the serum HCV-RNA by nested-PCR and HCV genotype by hybridization of the amplified sequence from the 5'-non-coding region. The cut-off value of ALT was obtained from a ROC curve. RESULTS: Within the 217 patients, 18 (8.3%) were anti-HCV-positive, 17 (7.8%) of whom were also HCV-RNA-positive. Genotype distribution was: 1a=47%; 1b=18%; 3a=35%. Mean ALT/ULN (0.77+/-0.57) of the 18 anti-HCV-positive cases was higher (p<0.001) than the negative group (0.38+/-0.23). The mean ALT/ULN (0.81+/-0.57) of the 17 HCV-RNA-positive cases was also higher (p<0.0001) than the negative cases (0.37+/-0.23). The cut-off value of ALT to distinguish the anti-HCV-positive from negative patients was 0.50% or 50% of the ULN (sensitivity=67%; specificity=83%). According to the HCV-RNA, the cut-off value of ALT was 0.45% or 45% of the ULN (sensitivity=71%; specificity=80%). CONCLUSION: Reducing the cut-off of ALT by half, enables a better identification of biochemical activity in patients with HCV infection on chronic HD.  相似文献   
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Hamartomas were first described by Albrecht in 1904, who defined them as tumor-like malformations in which there was abnormal blending of the normal components of an organ. The myoid hamartoma is a rare benign lesion of the breast and has an uncertain origin, possibly in the walls of the blood vessels, muscularis mammillae of the areolae, and mainly in myoepithelium. We report 3 cases of myoid hamartomas of the breast, with the clinical, radiologic, and histopathological findings, and review the literature. The 3 lesions showed normal breast ducts and lobules, entrapped by a muscular stroma and some foci of mature adipose tissue. The muscular origin of part of the stroma was confirmed by strong reactiveness with smooth-muscle actin.  相似文献   
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A sample of aphthovirus type C3 strain Resende carrying two polyribocytidilic acid [poly(C)] tracts was cloned in tissue culture. One clone with a poly(C)-rich tract of about 145 nucleotides long (clone 3B) and another with a poly(C)-rich tract of about 230 nucleotides long (clone 12) and a mixture of both were injected intralingually into three steers. Samples from all three animals were recovered during the acute phase of the disease, from the blood and from the feet, and at various days after inoculation from the oesophageal-pharyngeal (OP) fluids. Analysis of the viral RNAs of the positive samples by means of RNase T1 maps on one- and two-dimensional gels showed (1) changes in the electrophoretic mobility of the poly(C)-rich tracts of viruses recovered from the OP fluids at various times after infection; (2) selection of virus populations with poly(C)-rich tracts of increased size; (3) later on, changes in the patterns of oligonucleotides of persistent viruses. These variations may lead to the production of new strains with altered biological properties that may contribute to the maintenance and spread of these viruses in the field.  相似文献   
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Summary The effect of various polycations on the immune response potentiated with poly I:C was studied. It was found that low molecular weight polycations had no potentiating effect. Polylysine was ineffective whereas protamine was superior to lysozyme, poly-arginine, poly-histidine, DEAE-Dextran and histone.A foot-and-mouth disease trivalent vaccine composed of strains A24 Cruzeiro, O1 Caseros and C2 Resende elicited no immune response in swine when adjuvanted with aluminium hydroxide but was effective when emulsified in oil. In general, the immune response was potentiated ten-fold when the emulsion contained poly I:C. The antibody production was in most cases further potentiated by a factor of ten when the nucleic acid double-strand was complexed with 1:10 (w/w) DEAE-Dextran. Protamine was as effective, or perhaps even more, than DEAE-Dextran to this effect.Guinea pigs vaccinated with a water-in-oil emulsion type monovalent C3 vaccine showed an increase in antibody production when the vaccine contained poly I:C or poly I:C complexed with 1:10 (w/w) protamine.With 4 Figures  相似文献   
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