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131.
Lam S Bux S Kumar G Ng Kh Hussain A 《Biomedical imaging and intervention journal》2009,5(3):e13-Sep;5(3):e13
Purpose
To compare the image quality of the low-dose to the standard-dose protocol of MDCT scanning of the paranasal sinuses, based on subjective assessment and determine the radiation doses to the eyes and thyroid gland and dose reduction between these two protocols.Materials and Methods
31 adult patients were scanned. Prior to scanning, thermoluminescent dosimeters (TLDs) were placed at 4 sites: outer canthus of right eye, outer canthus of left eye, inner canthus and anterior neck (thyroid gland). Every patient was scanned twice using the standard-dose protocol (100mAs) followed by the low-dose protocol (40mAs). The images were reviewed by 3 radiologists. Wilcoxon test was used as the test of significance for the image quality assessments. The paired sample t-test was used as the test of significance for the analysis of the radiation doses measured by the TLDs.Results
Of the 30 patients selected for analysis, this study showed no significant difference in the scores for the diagnostic image quality and the anatomical structures assessments between the two protocols. The average calculated mean entrance surface doses and standard deviation for the standard-dose and low-dose protocols were 12.40±1.39 mGy and 5.53±0.82 mGy respectively to the lens and 1.03±0.55 mGy and 0.63±0.53 mGy respectively to the thyroid gland.Conclusion
The reduction of mAs from 100 to 40 resulted in a significant reduction of the radiation doses to the lens and thyroid gland by 55.4% and 38.8% respectively without causing any significant effect to the diagnostic image quality and assessment of the anatomical structures. 相似文献132.
BACKGROUND: The neutrophil-specific CD 177 molecule (NB1 glycoprotein/HNA-2a) has gained clinical interest because of its involvement in severe antibody-dependent diseases like transfusion-related acute lung injury and neonatal alloimmune neutropenia. Up regulation of CD 177 in response to different stimuli (granulocyte-colony-stimulating factor, N-formyl-Met-Leu-Phe, bacterial infections) has been described in adults. STUDY DESIGN AND METHODS: The regulation of CD 177 expression was evaluated on mRNA and glycoprotein levels from cord blood neutrophils of 56 neonates, 38 of them with complications during pregnancy or delivery. Real-time polymerase chain reaction and flow cytometry were used for quantification. RESULTS: White blood cells from neonates of both sexes showed significantly elevated glycoprotein and mRNA levels compared to adults. In addition, there was a significant mRNA up regulation in female newborns predominantly occurring in cases with pathologic cardiotocogram, premature rupture of the amniotic membrane, and health disorders of the mother. CONCLUSION: These findings show a significantly increased CD 177 expression in neutrophils from newborns compared to adults, which suggests the existence of additional factors being able to stimulate CD 177 expression. 相似文献
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Najla Mezghani Emna Mkaouar-Rebai Mouna Mnif Nadia Charfi Nabila Rekik Saoussan Youssef Mohamed Abid Faiza Fakhfakh 《Journal of diabetes and its complications》2010,24(4):270-277
Diabetes mellitus (DM) is a heterogeneous disorder characterized by the presence of chronic hyperglycemia. Genetic factors play an important role in the development of this disorder, and several studies reported mutations in nuclear genes implicated in the insulin function. Besides, DM can be maternally transmitted in some families, possibly due to the maternal mitochondrial inheritance. In fact, mitochondrial genes may be plausible causative agents for diabetes, since mitochondrial oxidative phosphorylation plays an important role in glucose-stimulated insulin secretion from beta cells.Materials and MethodsIn this report, we screened two Tunisian families with mitochondrial diabetes for the m.3243A>G and the m.14709T>C mutations, respectively, in the tRNALeu(UUR) and the tRNAGlu genes.ResultsThe polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) and the sequence-specific primers by polymerase chain reaction (SSP-PCR) analysis in the leucocytes and the buccal mucosa in the members of the two families showed the absence of the m.3243A>G mutation and the presence of the heteroplasmic m.14709T>C mutation in the tRNAGlu gene in the two tested tissues.ConclusionsWe conclude that the m.14709T>C mutation in the tRNAGlu gene could be a cause of mitochondrial diabetes in Tunisian affected families. In addition, the heteroplasmic loads correlated with the severity and the onset of mitochondrial diabetes in one family but not in the other, suggesting the presence of environmental factors or nuclear modifier genes. 相似文献
135.
Schmitz N Admiraal-Behloul F Arkink EB Kruit MC Schoonman GG Ferrari MD van Buchem MA 《Headache》2008,48(7):1044-1055
Objective.— The aim of this study was to pinpoint predilection sites of brain damage in migraine by quantitatively identifying morphometric and diffusion differences in migraineurs, compared with control subjects, and to assess whether migraine attack frequency and attack history are indicators for brain abnormalities in migraineurs.
Background.— Previous clinical neuroimaging investigations introduced the concept of migraine as a progressive brain disease. They reported an increased risk of white matter hyperintensities (WMH) with increasing attack frequency in migraineurs.
Methods.— We investigated 28 patients with migraine, using high-resolution T1- and diffusion-weighted magnetic resonance imaging and optimized voxel-based morphometry to localize gray and WM density, and fractional anisotropy and apparent diffusion coefficient differences.
Results.— We identified predilection sites of brain abnormalities in migraineurs in the frontal lobes, brainstem, and the cerebellum, and we show that both attack frequency and disease duration are indicators for brain damage in migraine.
Conclusion.— Our findings report an unbiased quantitative whole brain assessment of morphological abnormalities in migraine. This might help to identify indicators for migraine as a possibly progressive brain disease. In order to reveal the causes and consequences of brain damage in migraine, further neuroimaging studies have to investigate quantitative brain changes in a longitudinal design. 相似文献
Background.— Previous clinical neuroimaging investigations introduced the concept of migraine as a progressive brain disease. They reported an increased risk of white matter hyperintensities (WMH) with increasing attack frequency in migraineurs.
Methods.— We investigated 28 patients with migraine, using high-resolution T1- and diffusion-weighted magnetic resonance imaging and optimized voxel-based morphometry to localize gray and WM density, and fractional anisotropy and apparent diffusion coefficient differences.
Results.— We identified predilection sites of brain abnormalities in migraineurs in the frontal lobes, brainstem, and the cerebellum, and we show that both attack frequency and disease duration are indicators for brain damage in migraine.
Conclusion.— Our findings report an unbiased quantitative whole brain assessment of morphological abnormalities in migraine. This might help to identify indicators for migraine as a possibly progressive brain disease. In order to reveal the causes and consequences of brain damage in migraine, further neuroimaging studies have to investigate quantitative brain changes in a longitudinal design. 相似文献
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Current UK child mental health policy seeks to engage primary care personnel in improving service delivery under the heading of 'Comprehensive CAMHS' but little is known about the size of this resource, the sufficiency of its training or its commitment to children's mental health. We surveyed local health, education and social services agencies within a UK Unitary Authority just outside London, using both questionnaire and focus group methodologies: 150 primary care personnel were identified in 14 teams. Of these 122 participated in the questionnaire survey, and 60 took part in focus groups. There was, approximately, one such team member for every 30 children with a mental health problem. Respondents reported deficiencies in skills and knowledge, but wanted training and support to increase their involvement provided it related to their daily practice, professional roles, and was developed in accordance with local needs and resources. Lack of training and organization impedes the effective deployment of a potentially huge resource for children with mental health problems. This could be addressed by appropriately tailored training courses, combined with managerial work on systems and remits. Such a programme would be needed to realize the National Service Framework's concept of a 'comprehensive CAMHS'. 相似文献
138.
Yetish Sing Sumeshini Subrayan Buhle Mqadi Pratistadevi K. Ramdial Jenendhiran Reddy Manogran S. Moodley Shamim Bux 《Pathology international》2010,60(9):621-625
Plexiform angiomyxoid myofibroblastic tumor (PAMT) is a relatively recently described gastric tumor with a peculiar plexiform growth pattern. PAMT is typified by a myofibroblastic immunophenotype that distinguishes it from the more common gastrointestinal stromal tumors and the rarely documented fibromyxomas. We report an additional PAMT, the seventh tumor with this label, which was an incidental finding on abdominal computed tomography scan of a 35‐year‐old Indian female. The tumor measured 4 × 3 × 2 cm and demonstrated plexiform architecture, myxoid stroma, prominent vasculature and spindled cells with myofibroblastic differentiation. The clinicopathological features, progesterone immunopositivity, hitherto undocumented, and mimicry of other primary and secondary gastric mesenchymal tumors, including endometrial stromal sarcoma, are discussed. 相似文献
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140.
Antibody-induced neutrophil activation as a trigger for transfusion-related acute lung injury in an ex vivo rat lung model 总被引:1,自引:1,他引:0
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Transfusion-related acute lung injury (TRALI) is a hazardous complication of transfusion and has become the leading cause of transfusion-related death in the United States and United Kingdom. Although leukoagglutinating antibodies have been frequently shown to be associated with the syndrome, the mechanism by which they induce TRALI is poorly understood. Therefore, we reproduced TRALI in an ex vivo rat lung model. Our data demonstrate that TRALI induction by antileukocyte antibodies is dependent on the density of the cognate antigen but does not necessarily require leukoagglutinating properties of the antibody or the presence of complement proteins. Rather, antibody-mediated activation of neutrophils seems to initiate TRALI, a process that could be triggered by neutrophil stimulation with fMLP. Antibody-mediated neutrophil activation and subsequent release of reactive oxygen species may thus represent key events in the pathophysiologic cascade that leads to immune TRALI. 相似文献