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1.
2.
Introduction: Features of spiral CT (SCT) — fast scanning, dynamic injection of contrast allowing optimal vessel opacification, and supplemental multiplanar imaging — promises to provide increased accuracy in the diagnosis of acute and non acute thoracic vascular disease. Recent work demonstrating the cost effective triage of hemodynamically stable patients after blunt chest trauma for angiography based on dynamic CT findings has prompted an investigation into the accuracy of SCT in this clinical setting. Methods: A retrospective review of all patients seen in the emergency department over the period of one year for aortic, thoracic, or blunt chest trauma evaluation was performed (74 patients) and all SCT scans available were reviewed and data reformatted for optimal delineation of pathology using maximum intensity projection and multiplanar reformation. The accuracy and predictive positive and negative values of SCT were calculated with respect to angiography, surgical, and/or clinical follow up evaluation. Results: Twenty three (31%) patients went directly to angiography owing to mediastinal widening on chest film and hemodynamic instability, of which four were positive and required emergent surgery. Seven hemodynamically stable patients (9%) had noncontrast SCT owing to mediastinal widening on chest film, all of which had angiography with none having great vessel trauma. Fourty four hemodynamically stable patients (60%) had contrast enhanced SCT (ceSCT), of which five (11%) were abnormal and underwent angiography, four of these were positive for aortic damage, one for a subclavian artery laceration. Of the remaining 39 patients who had normal ceSCT; five had angiography, all of which were normal. Of the remaining 34 patients that had normal ceSCT none had adverse outcome on clinical follow-up, minimum of 12 months. Conclusion: The predictive positive value for aortic trauma of ceSCT in blunt trauma is 80%, with a predictive negative value of 100%, indicating that it is feasible for SCT to be a first line exam in blunt chest trauma in the future.  相似文献   
3.
A cross-sectional study was conducted among 395 patients presenting with genital ulcers at a primary health care centre in Kigali, Rwanda. Using clinical data and the results of a rapid plasma reagin (RPR) test, we simulated the diagnostic outcome of two simple WHO flowcharts for the management of genital ulcers. These outcomes and a clinical diagnosis were then compared with the laboratory diagnosis based on culture for genital herpes and Haemophilus ducreyi and serology for syphilis. The prevalence of HIV infection was high (73%) but there was no difference between HIV-positive and HIV-negative patients in the clinical presentation and etiology of genital ulcer disease. The proportion of correctly managed chancroid and/or syphilis cases was 99% using a syndromic approach, 82.1% using a hierarchical algorithm including an RPR test, and 38.3% with a clinical diagnosis. In situations where no laboratory support is available, a simple syndromic approach is preferable to the clinical approach for the management of genital ulcer. If an RPR test can be included in the diagnostic strategy, patients with a reactive RPR test should be treated for both syphilis and chancroid infection.  相似文献   
4.
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   
5.
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   
6.
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   
7.

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   
8.
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   
9.
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.
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   
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