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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
M C F Bouzada E A Oliveira A K Pereira H V Leite A M Rodrigues L A Fagundes R P Gon?alves R L Parreiras 《Ultrasound in obstetrics & gynecology》2004,24(7):745-749
OBJECTIVE: The purpose of this study was to assess the accuracy of prenatal ultrasound measurement of anteroposterior renal pelvis diameter (APD) to discriminate between significant uropathy and idiopathic renal pelvis dilatation. METHODS: One-hundred-and-three neonates who were found to have fetal renal pelvis dilatation, defined as presence of an APD > or = 5 mm, underwent systematic investigation for uropathies and were prospectively followed. An ultrasound scan was performed after the first week of postnatal life and all infants underwent a voiding cystourethrogram. Neonates with an APD larger than 10 mm underwent renal scintigraphy. Ultrasound scans, clinical examination and laboratory reviews were scheduled at 6-month intervals. Receiver-operating characteristics (ROC) curves were constructed to determine the best cut-offs for APD to identify renal units with significant uropathy as well as those requiring surgical intervention. Significant uropathy was defined as the presence of well-established urinary tract abnormalities or when there was abnormal renal scintigraphy. RESULTS: The estimated area under the curve for APD was 0.900 (95% CI, 0.841-0.942) indicating excellent power to discriminate between idiopathic pelvis dilatation and significant uropathy. The sensitivity and specificity for the 7.5 mm cut-off point were 97.9% and 40.6%, respectively. To identify infants who required surgical intervention, the calculated area under the curve was 0.953 (95% CI, 0.908-0.980). CONCLUSION: Our results suggest that measurement of APD is an excellent test to identify fetuses with significant uropathy, as well as those requiring postnatal intervention. 相似文献
42.
W. E. Uber S. E. Self A. B. Van Bakel N. L. Pereira 《American journal of transplantation》2007,7(9):2064-2074
Acute antibody-mediated rejection (AMR) in heart transplantation is often associated with hemodynamic compromise, and is associated with increased mortality and development of accelerated transplant coronary artery disease (TCAD). The diagnosis of AMR has historically been controversial and outcomes with aggressive immunosuppressive therapy including plasmapheresis and cyclophosphamide are poor. Advances in diagnostic techniques like the demonstration of immunopathologic evidence for antibody-mediated rejection by deposition of the complement split product C4d in tissue and detection of anti-HLA antibodies by flow cytometry will assist in further characterizing AMR. Immunosuppression targeting B-lymphocytes and use of m-TOR inhibitors to alter the predilection to develop TCAD and improve survival in AMR remains to be proven. 相似文献
43.
44.
Because of its numerous etiologies, foot dermatitis can be difficult to diagnose despite of thorough history and physical examination. The differential diagnoses are challenging and include allergic contact dermatitis, dyshidrosis, juvenile plantar dermatosis, atopic dermatitis, lichen planus.
Methods: In the Cutaneous Allergology Unit of the Department of Dermatovenereology of Pedro Hispano Hospital, between 1999 and 2003, 804 patients were observed with suspicion of contact dermatitis. In 9,3% there was a history of recurrent foot dermatitis. All these patients were patch tested with GPEDC standard and shoe series and shoe fragments.
Results: Twenty‐five patients revealed shoe contact dermatitis with positive reactions to the series tested, with an average age of 40 years. The dermatitis involved the dorsal aspect of the foot in 20 patients and the volar aspect in 8, the lateral aspects in 4, typically sparing the instep and flexural creases of the toes. The most common allergen were para‐tertiary‐butylphenol formaldehyde resin – PTBFR (12 patients‐48%), mercapto mix (7 patients‐28%), potassium dichromate (24%), mercaptobenzothiazole (24%).
Conclusions: The most common causes of shoe contact dermatitis were glues, followed by rubber components and chromated leather. As in other studies the most common allergen in shoe dermatitis in Portugal is PTBFR in neoprene adhesives. Rubber components (accelerators) were the second more frequent allergen in this study, probably a direct result of improved fixation of chrome and a change in footwear style and chrome sensitivity explains leather allergy. Other causes of foot contact dermatitis are iatrogenic complication, clothing (socks), cosmetics, adhesive tape and professional etiology. 相似文献
Methods: In the Cutaneous Allergology Unit of the Department of Dermatovenereology of Pedro Hispano Hospital, between 1999 and 2003, 804 patients were observed with suspicion of contact dermatitis. In 9,3% there was a history of recurrent foot dermatitis. All these patients were patch tested with GPEDC standard and shoe series and shoe fragments.
Results: Twenty‐five patients revealed shoe contact dermatitis with positive reactions to the series tested, with an average age of 40 years. The dermatitis involved the dorsal aspect of the foot in 20 patients and the volar aspect in 8, the lateral aspects in 4, typically sparing the instep and flexural creases of the toes. The most common allergen were para‐tertiary‐butylphenol formaldehyde resin – PTBFR (12 patients‐48%), mercapto mix (7 patients‐28%), potassium dichromate (24%), mercaptobenzothiazole (24%).
Conclusions: The most common causes of shoe contact dermatitis were glues, followed by rubber components and chromated leather. As in other studies the most common allergen in shoe dermatitis in Portugal is PTBFR in neoprene adhesives. Rubber components (accelerators) were the second more frequent allergen in this study, probably a direct result of improved fixation of chrome and a change in footwear style and chrome sensitivity explains leather allergy. Other causes of foot contact dermatitis are iatrogenic complication, clothing (socks), cosmetics, adhesive tape and professional etiology. 相似文献
45.
Changes in Avidity and Level of Immunoglobulin G Antibodies to Mycobacterium tuberculosis in Sera of Patients Undergoing Treatment for Pulmonary Tuberculosis
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Lenka M. Pereira Arias-Bouda Sjoukje Kuijper Anouk Van Der Werf Lan N. Nguyen Henk M. Jansen Arend H. J. Kolk 《Clinical and Vaccine Immunology : CVI》2003,10(4):702-709
Much is known about specific antibodies and their titers in patients with tuberculosis. However, little is known about the avidity of these antibodies or whether changes in avidity occur during the progression of the disease or during treatment. The aims of this study were to determine the avidity of antibodies to Mycobacterium tuberculosis in patients with pulmonary tuberculosis, to explore the value of avidity determination for the diagnosis of tuberculosis, and to study changes in levels of antibodies and their avidity during treatment. Antibody avidity was measured by an enzyme-linked immunosorbent assay with thiocyanate elution. Avidity indices and serum levels of immunoglobulin G to M. tuberculosis were determined for 22 patients with pulmonary tuberculosis before and during treatment and for 24 patients with other pulmonary diseases. Antibody levels and avidity were both significantly higher in untreated tuberculosis patients than in the controls. Avidity determination had more diagnostic potential than determination of the antibody levels. Tuberculosis patients with a long duration of symptoms had higher antibody avidity than those with a recent onset of symptoms, indicating affinity maturation of specific antibodies during active disease. In the early phase of treatment, a decrease in antibody avidity was observed for 73% of all tuberculosis patients, accompanied by an initial increase in antibody levels in 36% of these patients. These phenomena could be explained by an intense stimulation of the humoral response by antigens released from killed bacteria, reflecting early bactericidal activity of antituberculous drugs leading to the production of low-affinity antibodies against these released antigens. 相似文献
46.
Genomic analysis of the nuclear receptor family: new insights into structure, regulation, and evolution from the rat genome
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Zhang Z Burch PE Cooney AJ Lanz RB Pereira FA Wu J Gibbs RA Weinstock G Wheeler DA 《Genome research》2004,14(4):580-590
Completion of the Rattus norvegicus genome sequence enabled a global inventory and analysis of the nuclear receptors (NRs) in three mammalian species. Forty-nine NR members were found in mouse, 48 in human. Forty-seven were found in the rat, with gaps at the locations expected for the other two. Pairwise comparisons of their distribution in rat, mouse, and human identified 11 syntenic NR gene blocks, including three small clusters of two or three closely related genes, each spanning 40 kb to 1700 kb. The exon structure of the ligand-binding domain suggests that exon shuffling has played a role in the evolution of this family. An invariant splice junction in all members of the NR family except LXRbeta suggests a functional role for the intron. The ligand-binding domains of PXR and CAR are among the most divergent in the family. Their higher nucleotide substitution rates may be related to the central role played by these two NRs in the metabolism of the foreign compounds and may have resulted from limited positive selection. 相似文献
47.
F G Araujo P M Coelho L H Pereira J Pellegrino 《Clinical and experimental immunology》1977,28(2):289-291
Skin-graft rejection in mice experimentally infected with Schistosoma mansoni is delayed when grafting is performed 60 days after the infection. In mice infected 30 days prior to the grafting, the grafts were rejected at the same time both in infected and in control animals. This observation indicates that impairment of cell-mediated immune response occurs in mice with mature S. mansoni infections. 相似文献
48.
Herpes simplex virus 1 (HSV-1) glycoprotein B (gB) is one of several envelope glycoproteins required for virion infectivity and is the only one known to oligomerize into homodimers. To study the conformational constraints for translocation of HSV-1 gB to the surface of eukaryotic cells, we analyzed the transport through the exocytic pathway of the wild-type glycoprotein and of mutant forms with insertions in the ectodomain and intracellular carboxy terminus. Transient expression of the glycoproteins in COS-1 cells showed that an insertion at position 479 in the amino-terminal ectodomain of gB, shown previously by reactions with monoclonal antibodies to have altered the conformation of the molecule, also had a drastic effect on transport, precluding exit of the mutant from the endoplasmic reticulum (ER) and transport to the Golgi and the plasma membrane. The fact that the mutant, gB-(Lk479), formed dimers suggests that local changes in assembled regions caused the transport defect. Mutants containing insertions at residues 600 of the ectodomain and 810 in the intracellular domain were slightly retarded in their rate of transport from the ER to the Golgi. The glucose-regulated proteins GRP78 and GRP94, which are resident proteins of the ER, associated with partially glycosylated, faster-migrating forms of gB but not with the fully processed, more slowly migrating product. GRP78 and GRP94 formed complexes with the mutant gB-(Lk479), which was degraded in the ER. Our results indicate that GRP78, and perhaps also GRP94, acts as a chaperone in the assembly of native gB oligomers and also binds to aberrant forms of the molecule, arresting their transport from the ER and possibly serving as markers for protein degradation in this compartment of the exocytic pathway. 相似文献
49.
Sputum Cytokine Levels in Patients with Pulmonary Tuberculosis as Early Markers of Mycobacterial Clearance
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Rodrigo Ribeiro-Rodrigues Tatiana Resende Co John L. Johnson Fabiola Ribeiro Moises Palaci Ricardo T. S Ethel L. Maciel Fausto E. Pereira Lima Valderio Dettoni Zahra Toossi W. Henry Boom Reynaldo Dietze Jerrold J. Ellner Christina S. Hirsch 《Clinical and Vaccine Immunology : CVI》2002,9(4):818-823
Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-γ) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-γ levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-γ levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-γ immunoreactivities in serum followed kinetics in sputum. TNF-α, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-γ, however, TNF-α and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy. 相似文献
50.