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31.
Trypanosoma cruzi, the protozoan parasite that causes human Chagas' disease, induces a type I interferon (IFN) (IFN-α/β) response during acute experimental infection in mice and in isolated primary cell types. To examine the potential impact of the type I IFN response in shaping outcomes in experimental T. cruzi infection, groups of wild-type (WT) and type I IFN receptor-deficient (IFNAR(-/-)) 129sv/ev mice were infected with two different T. cruzi strains under lethal and sublethal conditions and several parameters were measured during the acute stage of infection. The results demonstrate that type I IFNs are not required for early host protection against T. cruzi. In contrast, under conditions of lethal T. cruzi challenge, WT mice succumbed to infection whereas IFNAR(-/-) mice were ultimately able to control parasite growth and survive. T. cruzi clearance in and survival of IFNAR(-/-) mice were accompanied by higher levels of IFN-γ production by isolated splenocytes in response to parasite antigen. The suppression of IFN-γ in splenocytes from WT mice was independent of IL-10 levels. While the impact of type I IFNs on the production of IFN-γ and other cytokines/chemokines remains to be fully determined in the context of T. cruzi infection, our data suggest that, under conditions of high parasite burden, type I IFNs negatively impact IFN-γ production, initiating a detrimental cycle that contributes to the ultimate failure to control infection. These findings are consistent with a growing theme in the microbial pathogenesis field in which type I IFNs can be detrimental to the host in a variety of nonviral pathogen infection models. 相似文献
32.
发生于骶骨以上的脊柱骨巨细胞瘤罕见[1],关于其CT表现仅见零星个案报道。我院误诊1例,报告如下。患者男性,20岁。胸背部疼痛2月,加重伴双下肢麻木10天入院。病史中无明显咳嗽、潮热、盗汗现象。外院X线及CT提示第5胸椎体结核伴椎旁冷脓肿形成。专科检查:胸椎活动受限,尤以屈曲位为明显,第5胸椎处叩压痛明显,局部无明显畸形及包块,剑突平面以下痛觉略减退,双下肢踝阵挛阳性,双膝反射、踝反射亢进。实验室检查:肝功、肾功、电解质、CEA、AFP及血、尿常规均无异常,入院时ESR:41mm/h,1周后复查ESR:16mm/h,2周后复查ESR:37mm/h。影像表… 相似文献
33.
Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis 总被引:1,自引:0,他引:1
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent. 相似文献
34.
Speech-controlled generation of radiology reports 总被引:1,自引:0,他引:1
Robbins AH; Horowitz DM; Srinivasan MK; Vincent ME; Shaffer K; Sadowsky NL; Sonnenfeld M 《Radiology》1987,164(2):569-573
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%. 相似文献
35.
Specific immunoradiometric assay of insulin-like growth factor I with use of monoclonal antibodies 总被引:1,自引:0,他引:1
M G Scott G C Cuca J R Petersen L R Lyle B D Burleigh W H Daughaday 《Clinical chemistry》1987,33(11):2019-2023
We identified two monoclonal antibodies that bind spatially distinct epitopes on insulin-like growth factor I (IGF-I). Using these two antibodies, we developed a simultaneous, two-site immunoradiometric assay (IRMA) specific for IGF-I. This IRMA has no detectable cross reactivity with insulin, proinsulin, prolactin, or somatotropin, and less than 2% crossreactivity with IGF-II. The assay response varies linearly with IGF-I concentrations of 0-800 micrograms/L in serum; the detection limit is about 10 micrograms/L. A comparison of 26 IGF-I serum values from the IRMA and from a previously reported IGF-I specific RIA gave a correlation coefficient of 0.96 with no substantial bias (slope = 1.10). IGF-I values for serum, as an aid in assessing growth abnormalities, are easily (only three pipetting steps) obtained in less than 4 h. 相似文献
36.
Delayed hepatic CT scanning: increased confidence and improved detection of hepatic metastases 总被引:1,自引:0,他引:1
Bernardino ME; Erwin BC; Steinberg HV; Baumgartner BR; Torres WE; Gedgaudas- McClees RK 《Radiology》1986,159(1):71-74
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary. 相似文献
37.
Mafee MF; Peyman GA; Grisolano JE; Fletcher ME; Spigos DG; Wehrli FW; Rasouli F; Capek V 《Radiology》1986,160(3):773-780
Twenty-one patients with intraocular disease were studied by magnetic resonance (MR) imaging and computed tomography (CT). In 13 cases, malignant uveal melanoma was considered the likely diagnosis. Both imaging methods were accurate in determining the location and size of uveal melanomas. MR imaging was superior for the assessment of possible associated retinal detachment, for assessment of vitreous change, and for differentiating uveal melanoma from choroidal hemangioma and choroidal detachment. A case of retinal gliosis could not be differentiated from uveal melanoma by either technique. Uveal melanomas appeared as hyperintense lesions on T1-weighted images and as hypointense lesions on T2-weighted images. High signal intensity of the vitreous was observed in patients with vitritis and in those who were thought to have protein leaking into the vitreous as a result of impairment of the retinal-blood barrier. 相似文献
38.
M Carrozzo A Elia V Mereu E Dametto ME Fasano R Broccoletti S Rendine A Amoroso 《Oral diseases》2011,17(3):309-313
Oral Diseases (2011) 17 , 309–313 Objectives: Oral Lichen Planus (OLP) is associated with hepatitis C virus (HCV) infection and resembles graft‐versus‐host disease (GVHD) both clinically and histologically. The killer cell immunoglobulin‐like receptor (KIR) genes encode a family of receptors expressed on NK and T cells and are supposed to play a significant role in GVHD and HCV infection. The aim of this study was to analyze the association among OLP, HCV infection and variants in KIR gene expression. Methods: A total of 81 patients with OLP (36 HCV+ve and 45 HCV?ve) and 217 healthy controls (HCV?ve) were typed for the presence of eight KIR genes and of HLA‐Cw* alleles by polymerase chain reaction‐sequence specific primer. Results: There were no significant differences in the frequency of the KIR genes and HLA‐C1/C2 group alleles between cases and controls. We only found a significant difference in the frequency of the gene KIR2DL2 between HCV+ve and HCV?ve OLP patients. Conclusions: The present data suggest that OLP is not associated with particular KIR genes or with HLA‐Cw* alleles in patients without HCV infection. Contrarily, the role of the genes in OLP‐HCV+ve patients remains unclear and might warrant further researches. 相似文献
39.
Choyke PL; Frank JA; Girton ME; Inscoe SW; Carvlin MJ; Black JL; Austin HA; Dwyer AJ 《Radiology》1989,170(3):713
40.