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151.
BACKGROUND AND PURPOSE: Quantitative MR imaging techniques such as magnetization transfer imaging (MTI), diffusion-weighted imaging (DWI), and MR spectroscopy are promising diagnostic tools for use with patients with diffuse brain diseases such as neuropsychiatric systemic lupus erythematosus (NPSLE). Such patients are often on corticosteroid (CS) treatment. Presently, it is unknown whether CSs per se influence quantitative MR imaging measurements. The aim of this study was to evaluate the effect of low-dose oral CSs on MTI, DWI, and MR spectroscopy parameters of the brain. METHODS: Twenty-seven rheumatoid arthritis (RA) patients with and without CS medication and 15 healthy controls were subjected to conventional MR imaging, whole-brain MTI and DWI, and single-voxel MR spectroscopy. Oral CSs were used by 13 of the RA patients. Univariate analyses with age as a covariate were performed on MTI, DWI, and MR spectroscopy parameters between RA patients with and without CSs and healthy controls. Pearson correlations were calculated between all imaging parameters and duration of disease, duration of CS use, and CS dosage. RESULTS: No significant differences between the groups of subjects or significant correlations with clinical parameters were found for MTI, DWI and MR spectroscopy parameters. CONCLUSION: In this study, we found no evidence for an effect of low-dose oral CSs on whole-brain MTI and DWI histogram parameters and single-voxel MR spectroscopy measurements of the brain. The results of this study demonstrate that it is unlikely that MTI, DWI, and MR spectroscopy parameters reported in NPSLE studies are confounded by low-dose oral CS.  相似文献   
152.
Intracerebral and non-central nervous system (non-CNS) cysticercosis caused by the larval pork tapeworm Taenia solium was diagnosed in patients in an Islamic state. The mode of transmission and challenges in diagnosis are highlighted. Sixteen patients with neurocysticercosis and six with non-CNS lesions were diagnosed by imaging studies (computerized tomography [CT]/magnetic resonance imaging [MRI]) and serology (ELISA and/or enzyme-linked immunoelectrotransfer blot assay [EITB]). Four of 55 family members, including servants, tested for antibodies were positive by the EITB and ELISA. Only one of these sera tested for antibodies to adult T. solium was positive: that of the cook, the probable source of the infection. We postulate a similar mode of transmission in the other Kuwaitis. Evaluation of several commercially available ELISA kits showed they were of poor specificity. Even in countries where pork consumption is proscribed by religious laws, physicians should include cysticercosis in their differential diagnosis in patients with neurological symptoms or non-CNS lesions, especially in non-endemic countries with a large expatriate population such as Kuwait. In children particularly, and in this region, suspected tuberculous lesions on CT must be investigated to rule out cysticerci by a more diligent use of the sensitive and specific EITB assay. Failure to understand the local epidemiology leads to empirical, inappropriate and prolonged therapy for chronic disease.  相似文献   
153.
BACKGROUND: Catheter angiography is traditionally used to determine renal arterial anatomy in live renal donors. Three-dimensional (3D) contrast-enhanced magnetic resonance imaging (MRA) has been suggested as a noninvasive replacement. We assessed the possibility of using MRA in live renal donors in Malaysia. METHODS: Twenty-six consecutive live renal donors were recruited from 2000 to 2002. All potential donors underwent evaluation of the renal arteries using both techniques. Angiographic findings from both modalities were subsequently compared with surgical findings at the time of donor nephrectomy. The total number and diameter of the arteries and the presence of early branching and renal abnormalities were noted. RESULTS: Both angiographic modalities were able to detect multiple renal arteries with catheter angiography having a sensitivity of 100% and MRA a sensitivity of 97%. MRA missed one 1-mm artery due to a low index of suspicion. Renal artery caliber measurements were not significantly different between the two methods. However, both techniques tended to overestimate the caliber of the renal arteries when compared with measurements taken at surgery. Early branching was found in two arteries at the time of surgery, but only one was detected by both techniques. Renal cysts seen on MR were not detected by catheter angiography. CONCLUSIONS: Our findings suggest that noninvasive MRA is a promising substitute for catheter angiography to evaluate the renal arteries of live donors.  相似文献   
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156.
A retrospective study, reviewing the medical records of 157 patients with a final diagnosis of tuberculosis on discharge, was conducted at King Abdul Aziz University Hospital during the period July 1999 to July 2001. The data included demographic characteristics, the spectrum of clinical presentations, diagnostic methods, and the outcome of treatment. A total of 157 patients were admitted with tuberculosis; their median age was 33(+/- 15.33) years. Fifty-seven (36%) were Saudis and 100 (64%) were non-Saudis. Pulmonary tuberculosis and pleural effusion were the commonest presentations (37.6%). Diagnosis was confirmed in most cases by either a positive sputum smear for AFB or by pleural biopsy; in five patients the diagnosis was made on clinical grounds and pleural fluid analysis. There was a wide spectrum of extra-pulmonary tuberculosis, diagnosed histologically except in five cases, in which treatment was started empirically based on high clinical suspicion and a strongly positive tuberculin test.  相似文献   
157.
Is it time to standardize granulocyte alloantigen nomenclature?   总被引:1,自引:0,他引:1  
Stroncek D  Bux J 《Transfusion》2002,42(4):393-395
  相似文献   
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159.
Unique endemicity of cryptosporidiosis in children in Kuwait   总被引:12,自引:0,他引:12  
To understand the transmission of Cryptosporidium infection in children, fecal specimens from 62 Kuwaiti children with gastrointestinal symptoms found to be positive by microscopy were genotyped and subtyped with a small subunit rRNA-based PCR-restriction fragment length polymorphism analysis and a 60-kDa glycoprotein-based DNA sequencing tool. The median age of infected children was 4.5 years, and 77% of infections occurred during the cool season of November to April. Fifty-eight of the children (94%) had Cryptosporidium parvum, three (5%) had Cryptosporidium hominis, and one (1%) had both C. parvum and C. hominis. Altogether, 13 subtypes of C. parvum (belonging to four subtype allele families) and C. hominis (belonging to three subtype allele families) were observed, with 92% of specimens belonging to the common allele family IIa and the unusual allele family IId. Thus, the transmission of cryptosporidiosis in Kuwaiti children differed significantly from other tropical countries.  相似文献   
160.
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