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排序方式: 共有1935条查询结果,搜索用时 515 毫秒
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Daniel Van Gansbeke Thierry M. Metens Celso Matos Nicole Nicaise France Gay Hubert Raeymaekers Julien Struyven 《Journal of magnetic resonance imaging : JMRI》1997,7(3):482-489
This study was devoted to tumor differentiation in liver MR T1-weighted imaging with superparamagnetic iron oxide (SPIO). Twenty-one patients with 40 liver lesions were studied at 1.5 T. Before and at least 45 minutes after SPIO administration, turbo-field-echo (TFE) T1-weighted, TFE T1 × T2*-weighted (MXT), and fat-suppressed turbo-spin-echo T2-weighted images were acquired. A quantitative analysis was performed blindly. On TFE T1-weighted images, the signal enhancement was ?33% ± 12 for the liver, ?24% ± 2 for adenomas and focal nodular hyperplasia, +60% ± 33 for the hemangiomas; metastases and cyst enhancement were not significant. After SPIO on TFE T1-weighted images, the hemangioma-to-liver signal ratio (149% ± 18) was definitely higher than the mean metastasis-to-liver signal ratio (90% ± 16). This T1-related differentiation ability lacked dramatically on TFE MXT images and, in one case, was reduced on post-SPIO TFE T1-weighted images by a long imaging delay after SPIO administration (2 hours). 相似文献
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Detection of Human T-Lymphotropic Virus (HTLV) tax Sequences in New York City Blood Donors Seronegative for HTLV Types 1 and 2 下载免费PDF全文
Charlene S. Dezzutti Patricia C. Guenthner Sylvester Daniel Ursula Utz Thania Cabrera James H. Marshall Celso Bianco Renu B. Lal Elliot P. Cowan 《Clinical and Vaccine Immunology : CVI》2003,10(4):715-717
A potential public health concern is the reported detection of the human T-lymphotropic virus (HTLV) tax gene in the lymphocytes of up to 11% of a low-risk group of New York City blood donors (NYBD). This study aimed to independently confirm the prevalence of HTLV tax sequences in 293 NYBD. All NYBD tested negative for antibodies to HTLV types 1 and 2 and HTLV Tax. HTLV tax sequences were not detected in the NYBD lymphocytes. These data demonstrate the lack of HTLV-1 tax in this group of NYBD at low risk for HTLV infection. 相似文献
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Dalton A Anjos Elba C S C Etchebehere Celso D Ramos Allan O Santos César Albertotti Edwaldo E Camargo 《Journal of nuclear medicine》2007,48(5):764-770
PET with (18)F-FDG has been considered of limited value for detection of bladder cancer because of the urinary excretion of the tracer. The purpose of this study was to investigate the role of PET/CT in the detection and restaging of bladder cancer using furosemide and oral hydration to remove the excreted (18)F-FDG from the bladder. METHODS: Seventeen patients with bladder cancer (11 without cystectomy, 6 with total cystectomy and urinary diversion) underwent (18)F-FDG PET/CT from head to the upper thighs 60 min after the intravenous injection of 370 MBq of (18)F-FDG. Additional pelvic images were acquired 1 h after the intravenous injection of furosemide and oral hydration. PET/CT findings were confirmed by MRI, cystoscopy, or biopsy. RESULTS: PET/CT was able to detect bladder lesions in 6 of 11 patients who had not undergone cystectomy. These images changed the PET/CT final reading in 7 patients: Recurrent bladder lesions were detected in 6 patients, pelvic lymph node metastases in 2 patients, and prostate metastasis in 1. This technique overcame the difficulties posed by the urinary excretion of (18)F-FDG. Hypermetabolic lesions could be easily detected by PET and precisely localized in the bladder wall, pelvic lymph nodes, or prostate by CT. Seven of 17 patients (41%) were upstaged only after delayed pelvic images. CONCLUSION: Detection of locally recurrent or residual bladder tumors can be dramatically improved using (18)F-FDG PET/CT with delayed images after a diuretic and oral hydration. 相似文献
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Santos AO Ueda-Nakamura T Dias Filho BP Veiga Junior VF Pinto AC Nakamura CV 《Journal of ethnopharmacology》2008,120(2):204-208
Ethnopharmacological relevance
Copaiba oil has been used in folk medicine since the 19th century. The use of copaiba oils to treat leishmaniasis is cited in several ethnopharmacological studies. Nevertheless, the potential antileishmania of copaiba oils had not been studied.Aim of the study
Eight different kinds of Brazilian copaiba oils were screened for antileishmanial activity.Materials and methods
The antiproliferative effect of copaiba oil on promastigote and amastigote axenic were determined. To determine the survival index peritoneal macrophage were infected with promastigotes of Leishmania amazonensis and treated with copaiba oil. The cytotoxic effect of copaiba oil was assessed on macrophage strain J774G8 by assay of sulforhodamine B.Results
Copaiba oils showed variable levels of activity against promastigote forms with IC50 values in the range between 5 and 22 μg/mL. The most active oil was that from Copaifera reticulata (collected in Pará State, Brazil) with IC50 values of 5, 15, and 20 μg/mL for promastigote, axenic amastigote and intracellular amastigote forms, respectively. Amphotericin B showed IC50 of 0.058 and 0.231 μg/mL against promastigote and amastigote forms, respectively. Cytotoxicity assay showed that this copaiba oil obtained from Copaifera reticulata showed low cytotoxicity against J774G8 macrophages.Conclusion
Copaiba oils showed significant activity against the parasite Leishmania amazonensis. 相似文献7.
Luzitano Brando Ferreira Celso Teixeira Mendes Cludia Emília Vieira Wiezel Marcelo Rizzatti Luizon Aguinaldo Luiz Simes 《American journal of human biology》2006,18(5):702-705
Allelic frequencies of eight autosomal short‐tandem repeat (STR) loci (TH01, TPOx, CSF1PO, vWA, FES/FPS, F13A1, F13B, and CD4) were determined in 400 individuals born in the State of São Paulo. No significant deviations from Hardy‐Weinberg equilibrium were found in any loci analyzed. The Unweighted Pair‐Group Method with Arithmetic Mean (UPGMA) tree constructed based on genetic distances revealed that the present population was grouped with Europeans, and separated from African and Amerindian populations. Estimates of admixture components based on the gene identity method revealed 79% European, 14% African, and 7% Amerindian contributions to this Brazilian population sample. Am. J. Hum. Biol. 18:702–705, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
8.
Knowledge and attitudes of primary health care personnel concerning mental health problems in developing countries: a follow-up study 总被引:1,自引:0,他引:1
L L Ignacio M V De Arango J Baltazar E D'Arrigo Busnello C E Climent A Elhakim R Giel T W Harding G H Ten Horn H H Ibrahim 《International journal of epidemiology》1989,18(3):669-673
Within the context of a World Health Organization coordinated collaborative study health workers in six developing countries were assessed 18 months after their training for improvement in their knowledge and attitude towards mental health problems and their management. The approaches to training varied between study areas, but the degree of improvement following the training, was of equal magnitude in all countries. The training process has formalized the recognition by the health workers that treatment of mental health problems is an integral part of their work. 相似文献
9.
Rocha AM Rocha GA Santos A de Oliveira CA Queiroz DM 《Journal of clinical microbiology》2003,41(1):447-448
We validated a commercial enzyme-linked immunosorbent assay for the detection of anti-CagA antibodies in Brazilian patients with Helicobacter pylori infection. The test presented high sensitivity (97.4%) and specificity (88.9%) when employed in patients without gastric carcinoma. However, in gastric carcinoma patients, the test was neither sensitive nor specific enough to detect cagA-positive H. pylori infection. 相似文献
10.
Toxoplasma gondii prevents neuron degeneration by interferon-gamma-activated microglia in a mechanism involving inhibition of inducible nitric oxide synthase and transforming growth factor-beta1 production by infected microglia 总被引:2,自引:0,他引:2 下载免费PDF全文
Rozenfeld C Martinez R Seabra S Sant'anna C Gonçalves JG Bozza M Moura-Neto V De Souza W 《The American journal of pathology》2005,167(4):1021-1031
Interferon (IFN)-gamma, the main cytokine responsible for immunological defense against Toxoplasma gondii, is essential in all infected tissues, including the central nervous system. However, IFN-gamma-activated microglia may cause tissue injury through production of toxic metabolites such as nitric oxide (NO), a potent inducer of central nervous system pathologies related to inflammatory neuronal disturbances. Despite potential NO toxicity, neurodegeneration is not commonly found during chronic T. gondii infection. In this study, we describe decreased NO production by IFN-gamma-activated microglial cells infected by T. gondii. This effect involved strong inhibition of iNOS expression in IFN-gamma-activated, infected microglia but not in uninfected neighboring cells. The inhibition of NO production and iNOS expression were parallel with recovery of neurite outgrowth when neurons were co-cultured with T. gondii-infected, IFN-gamma-activated microglia. In the presence of transforming growth factor (TGF)-beta1-neutralizing antibodies, the beneficial effect of the parasite on neurons was abrogated, and NO production reverted to levels similar to IFN-gamma-activated uninfected co-cultures. In addition, we observed Smad-2 nuclear translocation, a hallmark of TGF-beta1 downstream signaling, in infected microglial cultures, emphasizing an autocrine effect restricted to infected cells. Together, these data may explain a neuropreservation pattern observed during immunocompetent host infection that is dependent on T. gondii-triggered TGF-beta1 secretion by infected microglia. 相似文献