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Annals of Surgical Oncology - The role of sentinel lymph node biopsy (SLNB) when ductal carcinoma in situ with microinvasion (DCISM) is identified on core biopsy is unclear. Our aim was to assess...  相似文献   
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We have identified the A3243G heteroplasmic point mutation in mitochondrial DNA from a female patient with headache as the main clinical feature. The mitochondrial origin of her disease was only suspected because of her brother with MELAS syndrome. Morphological and biochemical studies failed to reveal mitochondrial respiratory chain dysfunction in her muscle which contained 65% of mutated mitochondrial DNA molecules. Molecular studies performed among four generations (in the blood of seven subjects) showed the variable transmission of mutated molecules and pointed out the difficulty in giving genetic counsel.  相似文献   
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Respiratory manifestations have been reported after exposure to hydroquinone and to methionine. One hundred and three men in the same chemical plant were divided into three groups according to their exposure and compared by questionnaire, respiratory functional tests with methacholine then salbutamol challenges, and measurements of serum immunoglobulins G and E. Group H included 33 workers exposed to hydroquinone, trimethyl-hydroquinone, and retinene-hydroquinone. Group M included 15 workers exposed to methionine. Group C was a control group of 55 workers. The prevalence of respiratory symptoms was higher in the two exposed groups. Before challenges, pulmonary function values were significantly lower in groups H and M than those in group C. The challenges induced significant variations in the three groups but these variations were less pronounced in group M than in the other groups. The level of immunoglobulin G in group H (m +/- SD = 12.5 gram/liter +/- 2.6) was significantly higher than in group C (10.6 gram/liter +/- 2.4; p less than 0.002). The level of immunoglobulin E in group H (m = 140 IU/l) was also higher in group C (109 IU/l) but this difference was not significant. These findings suggest that exposure to methionine and to hydroquinone and its derivatives induce ventilatory impairment, perhaps by an immunological mechanism.  相似文献   
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Hepatitis C virus (HCV) infection is a major public-health-care problem, with over 170 million infected worldwide. Patients with chronic HCV infection often complain of various cognitive problems as well as symptoms of depression, anxiety, and fatigue. Relatively little is known, however, about the specific cognitive deficits that are common among HCV patients, and the influence of psychiatric symptomatology on cognitive functioning. In the current study of 21 chronically infected HCV patients, we assessed subjective cognitive dysfunction, depression, anxiety, and fatigue and compared these symptom areas to cognitive tests assessing visuoconstruction, learning, memory, visual attention, psychomotor speed, and mental flexibility. Results revealed that cognitive impairment ranged from 9% of patients on a visuoconstruction task to 38% of patients on a measure of complex attention, visual scanning and tracking, and psychomotor speed, and greater HCV disease severity as indicated by liver fibrosis was associated with greater cognitive dysfunction. Objective cognitive impairment was not related to subjective cognitive complaints or psychiatric symptomatology. These findings suggest that a significant portion of patients with chronic HCV experience cognitive difficulties that may interfere with activities of daily living and quality of life. Future research using cognitive measures with HCV-infected patients may assist researchers in identifying if there is a direct effect of HCV infection on the brain and which patients may be more likely to progress to cirrhosis and hepatic encephalopathy.  相似文献   
7.
Disorders of the pyruvate dehydrogenase complex   总被引:3,自引:1,他引:2  
Pyruvate dehydrogenase deficiency may be a non-specific consequence of many different neurological degenerative disorders. There are also serious methodological problems in estimating the activity of this enzyme complex.  相似文献   
8.
Biochemical results concerning 64 patients suspected of mitochondrial myopathies are presented. Four clinical groups were studied including 21 encephalomyopathies, 42 ocular myopathies, 8 isolated myopathies and 3 cardiomyopathies. In 26 cases, the coexistence of a normal mitochondrial DNA and a mutated mitochondrial DNA (heteroplasmy) was found (19 simple deletions, 4 multiple deletions and 3 punctual mutations) and all cases presented with ocular disorders (excepted 2 cases with MERRF). Furthermore, 1 complex I deficiency (1 ocular myopathy), 1 complex IV deficiency (1 adult encephalomyopathy type Leigh), 3 complexes I + IV deficiencies (2 cases with a cardiomyopathy and 1 familial MELAS) and 2 pyruvate (1 adult from of Leigh's encephalomyopathy) dehydrogenase deficiencies (clinically and genetically different) did not show evidence of mitochondrial DNA mutation.  相似文献   
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Kearns-Sayre syndrome with sideroblastic anemia: molecular investigations.   总被引:2,自引:0,他引:2  
The progressive syndrome of Kearns-Sayre has been studied at the clinical, biochemical and genetic levels in a patient. Clinical arguments suggest an evolution from Pearson's disease to Kearns-Sayre syndrome. The respiratory chain activities were low, and Southern blot analysis, together with gene sequencing, showed a heteroplasmic deletion of 7767 base pairs in a significant proportion of the mitochondrial DNA in different tissues. Protein synthesis studies on lymphoblasts did not reveal any translation of the new reading frame created by the deletion, although the corresponding deleted mitochondrial DNA sequence is transcribed.  相似文献   
10.
Objective: To describe the development and reproducibility of a self‐report instrument, for use with children in years 4–6, to identify sources of food eaten during the day, and type and frequency of food purchases at school. Design: Tool development stages included formulation of content and format, expert review, piloting and a test–retest study. Subjects/setting: The pilot study included school students (n = 20) in years 4 and 5 (seven girls, mean age 9.7 ± 0.7 years) attending an Australian public primary school. The test–retest study was performed in a large metropolitan public primary school (n = 245 children, 52% female, mean age 10.7 ± 0.91 years) including children from years 4 (n = 88), 5 (n = 84) and 6 (n = 73). Statistical analysis: A Kappa statistic was used to assess level of agreement between the two time periods separated by 1 week. The results were analysed using SAS version 8.2 with each question compared at time 1 and 2. Results: The mean kappa was 0.529 using pairings from 17 questions. Values ranged from 0.18 to 0.71 (CI 0.46–0.60). Conclusions and applications: The School Eating Habits and Lifestyle Survey has been developed and pilot‐tested in primary school‐aged children and shown to have moderate stability over time. The results show that each phase of development, particularly those spent in consultation and testing, led to progressive improvement of this instrument. This process improved the quality of information produced and gave insights to self‐report of dietary intake and behaviours among children.  相似文献   
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