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81.
Supratentorial ependymoma: CT appearance 总被引:5,自引:0,他引:5
Armington WG; Osborn AG; Cubberley DA; Harnsberger HR; Boyer R; Naidich TP; Sherry RG 《Radiology》1985,157(2):367-372
The computed tomographic appearances of 22 biopsy-proved supratentorial ependymomas were analyzed. Supratentorial ependymomas were usually intraparenchymal, larger than 4 cm, and cystic. Contrast enhancement was moderate to intense, with homogeneous or ring-enhancement patterns commonly seen. Intratumoral calcification was present in one-third of the cases, while hydrocephalus and peritumoral edema were seen in 50%. Intratumoral hemorrhage was not a characteristic of the lesion. In contrast to cellular ependymomas, malignant ependymomas and ependymoblastomas demonstrate higher attenuation prior to administration of contrast material, more intense enhancement, lower frequency of calcification within the tumor, and less distinct margination. 相似文献
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Kohler KA Deshpande JM Gary HE Banerjee K Zuber PL Hlady WG 《Epidemiology and infection》2003,131(1):711-718
Acute flaccid paralysis (AFP) surveillance data from India were analysed to examine sensitivity of poliovirus isolation from stool specimens and the added sensitivity obtained from collection of a second stool specimen. Analysis was restricted to Indian AFP cases, 1998-2000, with two adequate stool specimens. The proportion of cases confirmed with wild poliovirus isolation by the second specimen only was calculated, regardless of specimen quality. Overall specimen sensitivity (1998-2000) was 81% using the first specimen, 78% using the second, and 96% using both. Sensitivity increased from 1998 to 2000, with slightly higher sensitivity each year for the first specimen. The second specimen increased sensitivity by 15% overall and contributed more when the first specimen was collected late or was in poor condition. As wild poliovirus disappears, increased sensitivity provided by a second stool specimen may reduce the risk of missing circulating virus. 相似文献
84.
Kohler KA Hlady WG Banerjee K Gupta D Francis P Durrani S Zuber PL Sutter RW 《Bulletin of the World Health Organization》2003,81(1):2-9
OBJECTIVE: To describe the characteristics of compatible poliomyelitis cases and to assess the programmatic implications of clusters of such cases in India. METHODS: We described the characteristics of compatible poliomyelitis cases, identified clusters of compatible cases (two or more in the same district or neighbouring districts within two months), and examined their relationship to wild poliovirus cases. FINDINGS: There were 362 compatible cases in 2000. The incidence of compatible cases was higher in districts with laboratory-confirmed poliomyelitis cases than in districts without laboratory-confirmed cases. Of 580 districts, 96 reported one compatible case and 72 reported two or more compatible cases. Among these 168 districts with at least one compatible case, 123 had internal or cross- border clusters of compatible cases. In 27 districts with clusters of compatible cases, no wild poliovirus was isolated either in the same district or in neighbouring districts. Three of these 27 districts presented laboratory-confirmed poliomyelitis cases during 2001. CONCLUSION: Most clusters of compatible cases occurred in districts identified as areas with continuing wild poliovirus transmission and where mopping-up vaccination campaigns were carried out. As certification nears, areas with compatible poliomyelitis cases should be investigated and deficiencies in surveillance should be corrected in order to ensure that certification is justified. 相似文献
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A detailed immunohistologic and cytogenetic analysis of 12 cases of intermediate lymphocytic lymphoma was performed. The characteristic immunophenotype of intermediate lymphocytic lymphoma was: surface IgM and IgD+, BA1+, B1+, BA2-, B2-, B4+, Leu 14+, Leu 1+, HLA-DR+, and common acute lymphocytic leukemia associated (CALLA) antigen negative. Clonal chromosome abnormalities were identified in ten cases, with structural or numerical abnormalities of chromosomes 11 or 12 in nine cases. Five cases had structural abnormalities involving the long arm of chromosome 11; three of these had translocations with chromosome 14 at band q32. Three cases had trisomy 12, and one case had a translocation involving the long arm of chromosome 12. The tenth case had a translocation involving the long arms of chromosomes 7 and 9. These characteristic immunophenotypic and cytogenetic findings suggest a close lineage relationship between intermediate lymphocytic lymphoma and small lymphocytic (well differentiated) lymphoma/chronic lymphocytic leukemia. Their differing clinical, cytologic, and architectural features suggest, however, that intermediate lymphocytic lymphoma should be considered a separate category of lymphocytic lymphoma in the International Working Formulation. 相似文献
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Plasma cytokine levels and monocyte activation in patients with obstructive jaundice 总被引:4,自引:0,他引:4
Some monocytic cytokines are important immune regulators. We have investigated cytokine production by monocytes and the blood levels of IL-1β, IL-6, TNFα, and TGFβ, in patients with obstructive jaundice. The supernatant from LPS stimulated monocytes from jaundiced patients released significantly increased quantities of TNFα by both bioassay and radioimmunoassay (RIA) (12.4 ± 2.5 fmol/mL and 32.6 ± 8.3 fmol/mL, respectively, for jaundice, compared with 1.6 ± 0.3 fmol/mL and 2.4 ± 0.5 fmol/mL respectively for controls, and also of IL-6 (54.8 ± 5.0 fmol/mL in jaundice compared with 35.6 ± 5.0 fmol/mL for controls). The production of IL-1β and TGFβ by stimulated monocytes was unchanged. Jaundiced patients had significantly higher plasma TGFβ, but TNFα and IL-1β were below the limits of detection. The highest monocyte TNFα and IL-6 levels were seen in malignant disease patients, especially those with a poor immediate prognosis. We conclude that the production of some cytokines by monocytes is up-regulated in patients with obstructive jaundice. 相似文献
90.
Edgar JG. Peters Didier Collard Sander Van Assen Martijn Beudel Marije K. Bomers Jacqueline Buijs Lianne R. De Haan Wouter De Ruijter Renée A. Douma Paul WG. Elbers Abraham Goorhuis Niels C. Gritters van den Oever Lieve GHH. Knarren Hazra S. Moeniralam Remy LM. Mostard Marian JR. Quanjel Auke C. Reidinga Roos Renckens Jonne J. Sikkens 《Clinical microbiology and infection》2021,27(2):264-268
ObjectiveTo compare survival of individuals with coronavirus disease 2019 (COVID-19) treated in hospitals that either did or did not routinely treat patients with hydroxychloroquine or chloroquine.MethodsWe analysed data of COVID-19 patients treated in nine hospitals in the Netherlands. Inclusion dates ranged from 27 February to 15 May 2020, when the Dutch national guidelines no longer supported the use of (hydroxy)chloroquine. Seven hospitals routinely treated patients with (hydroxy)chloroquine, two hospitals did not. Primary outcome was 21-day all-cause mortality. We performed a survival analysis using log-rank test and Cox regression with adjustment for age, sex and covariates based on premorbid health, disease severity and the use of steroids for adult respiratory distress syndrome, including dexamethasone.ResultsAmong 1949 individuals, 21-day mortality was 21.5% in 1596 patients treated in hospitals that routinely prescribed (hydroxy)chloroquine, and 15.0% in 353 patients treated in hospitals that did not. In the adjusted Cox regression models this difference disappeared, with an adjusted hazard ratio of 1.09 (95% CI 0.81–1.47). When stratified by treatment actually received in individual patients, the use of (hydroxy)chloroquine was associated with an increased 21-day mortality (HR 1.58; 95% CI 1.24–2.02) in the full model.ConclusionsAfter adjustment for confounders, mortality was not significantly different in hospitals that routinely treated patients with (hydroxy)chloroquine compared with hospitals that did not. We compared outcomes of hospital strategies rather than outcomes of individual patients to reduce the chance of indication bias. This study adds evidence against the use of (hydroxy)chloroquine in hospitalised patients with COVID-19. 相似文献