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991.
Hemangioma of the urinary bladder. 总被引:2,自引:0,他引:2
L Cheng A G Nascimento R M Neumann A Nehra J C Cheville D M Ramnani B C Leibovich D G Bostwick 《Cancer》1999,86(3):498-504
BACKGROUND: Hemangioma of the urinary bladder is rare and the long term outcome of patients is unknown. METHODS: The authors evaluated the clinical and pathologic findings in 19 patients with a vesical hemangioma. All patients were treated at the Mayo Clinic between 1932-1998 and had histologic confirmation of the diagnosis. Hemangioma was classified into cavernous, capillary, or arteriovenous types based on conventional criteria from other sites. Clinical information was obtained from chart review. The mean follow-up of the patients was 6.9 years (range, 0.3-25 years). RESULTS: The mean patient age at the time of diagnosis was 58 years (range, 19-76 years) and the male-to-female ratio was 3.7:1. Patients typically presented with macroscopic hematuria and endoscopic findings usually were nonspecific. The diagnosis of hemangioma was suspected in 3 patients (16%) prior to biopsy. There was a predilection for the posterior and lateral walls and the tumor usually was small (range, 0.2-3 cm; median, 0.7 cm) and solitary. The histologic types of hemangioma were cavernous (15 cases), capillary (2 cases), and arteriovenous (2 cases). All patients were treated with biopsy with or without fulguration, except for one patient who was treated with a partial cystectomy. No patients developed a recurrence during a mean follow-up of 6.9 years. CONCLUSIONS: Patients with hemangioma of the urinary bladder have a favorable outcome. Biopsy and fulguration are effective for hemangioma of the bladder when the lesion is small. 相似文献
992.
993.
William R. Sukov Ellen D. Remstein Antonio G. Nascimento Sanjeev Sethi Matthew Lewin 《Annals of diagnostic pathology》2009,13(2):127-131
Sclerosing extramedullary hematopoietic tumor (SEMHT) is a rare lesion that typically arises in patients with chronic myeloproliferative disorders. Morphologically, it exhibits atypical megakaryocytes, granulocytic precursors, and erythroid precursors set in a background of dense collagen sclerosis. Sclerosing extramedullary hematopoietic tumor may be easily mistaken for other neoplasms, such as sarcoma, carcinoma, or Hodgkin lymphoma, particularly if pertinent clinical history is not provided. Misdiagnosis may occur because of the difficulty in recognizing the megakaryocytic lineage of the atypical cells and because of the paucity of other hematopoietic elements. We report a case of a 72-year-old man with proteinuria and renal insufficiency who underwent renal biopsy to determine the etiology of the proteinuria. The kidney biopsy demonstrated an unusual tumor in which the initial morphological impression that of sclerosing liposarcoma. However, upon learning of the patient's previous history of chronic idiopathic myelofibrosis and with the aid of immunohistochemistry, the correct diagnosis of sclerosing extramedullary hematopoietic tumor was made. Sclerosing extramedullary hematopoietic tumor should be considered in the differential diagnosis when percutaneous renal biopsy or other intra-abdominal biopsy reveals a sclerotic lesion with interspersed large atypical cells, especially in a patient with a history of chronic myeloproliferative disorder. 相似文献
994.
995.
Ana Cristina Gobbo Cesar Luiz Fernando C Nascimento Jo?o Andrade de Carvalho Jr 《Revista de saúde pública》2013,47(6):1209-1212
The aim of this study was to estimate the association between exposure to
particulate matter less than 2.5 microns in diameter and hospitalization for
respiratory disease. It was an ecological time series study with daily
indicators of hospitalization for respiratory diseases in children up to 10
years old, living in Piracicaba, SP, Southeastern Brazil, between August 1, 2011
and July 31, 2012. A generalized additive Poisson regression model was used. The
relative risks were RR = 1.008; 95%CI 1.001;1.016 for lag 1 and
RR = 1.009; 95%CI 1.001;1.017 for lag 3. The increment of 10
μg/m3in particulate matter less than 2.5 microns in diameter
implies increase in relative risk of between 7.9 and 8.6 percentage points. In
conclusion, exposure to particulate matter less than 2.5 microns in diameter was
associated with hospitalization for respiratory disease in children. 相似文献
996.
997.
Bruna Daniella de Souza Silva Ediane Batista da Silva Ivan Pereira do Nascimento Michelle Cristina Guerreiro dos Reis André Kipnis Ana Paula Junqueira-Kipnis 《Vaccine》2009
Tuberculosis (TB) is a severe infectious disease that kills approximately two million people worldwide every year. Because BCG protection is variable and does not protects adults, there is a great need for a new vaccine against TB that does not represent a risk for immunocompromised patients and that is also capable of protecting adult individuals. MPT-51 is a protein found in the genome of mycobacteria and binds to the fibronectin of the extracellular matrix, which may have a role in host tissue attachment and virulence. In order to test the usefulness of MPT-51 as a subunit vaccine, BALB/c were vaccinated and challenged with Mycobacterium tuberculosis. The infection of BALB/c with M. tuberculosis increased the number of IFN-γ+ T lymphocytes specific to MPT-51 in the spleen and lungs. Inoculation with rMPT-51/FIA and with rMPT-51/CpG DNA in non-infected BALB/c increased the amounts of IFN-γ+ T lymphocytes. Inoculation with rMPT-51/FIA also induced a humoral response specific to MPT-51. CFU counts of lung tissues done 60 days after infection showed a reduction of about 2 log in the bacteria load in the group of animals inoculated with rMPT-51/CpG DNA. These results make MPT-51 a valuable component to be further evaluated in the development of other subunit vaccines. 相似文献
998.
Matthijs P Somford Frits W Draijer Bregje JW Thomassen Pascale M Chavassieux Georges Boivin Socrates E Papapoulos MD PhD 《Journal of bone and mineral research》2009,24(10):1736-1740
Unusual fractures of the femur diaphysis have been reported in patients treated with alendronate and, although no causal relationship has been established, excessive suppression of bone turnover and length of treatment with alendronate have been implicated in their pathogenesis. We report here clinical, biochemical, and radiological findings of a patient with rheumatoid arthritis and multiple risk factors for fractures who was treated with alendronate for 8 yr and developed spontaneous bilateral subtrochanteric/diaphyseal fractures. Bone biopsies obtained form the iliac crest and the femur showed decreased bone formation with histomorphometric evidence of markedly increased bone resorption at the femur. These results show for the first time that an imbalance between bone resorption and bone formation at the affected bone is associated with the occurrence of these atypical femur fractures. The cause of this imbalance is currently unknown, and further studies of the epidemiology and pathogenesis of diaphyseal femur fractures are warranted. 相似文献
999.
David H. Foster Sérgio M. C. Nascimento Kinjiro Amano Larry Arend Karina J. Linnell Juan Luis Nieves Sabrina Plet Jeffrey S. Foster 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(14):8151-8156
The perceived colors of reflecting surfaces generally remain stable despite changes in the spectrum of the illuminating light. This color constancy can be measured operationally by asking observers to distinguish illuminant changes on a scene from changes in the reflecting properties of the surfaces comprising it. It is shown here that during fast illuminant changes, simultaneous changes in spectral reflectance of one or more surfaces in an array of other surfaces can be readily detected almost independent of the numbers of surfaces, suggesting a preattentive, spatially parallel process. This process, which is perfect over a spatial window delimited by the anatomical fovea, may form an early input to a multistage analysis of surface color, providing the visual system with information about a rapidly changing world in advance of the generation of a more elaborate and stable perceptual representation. 相似文献
1000.