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41.
Amyotrophic lateral sclerosis (ALS) is generally considered to be a paradigm of pure motor neuron disorder; nevertheless, the possible occurrence of cognitive impairment up to a frank dementia in patients affected by ALS is recognized. The appraisal of the cognitive impairment in ALS patients is crucial not only to the therapeutic trials of this incurable disease, but also to the planning of care, compliance to interventions, the end-of-life decisions. The cognitive/behavioral changes of ALS patients are consistent with frontotemporal dysfunctions; the overlap of neuropathological features of ALS and frontotemporal lobe degeneration (FTLD) supports, in addition, the putative spectrum of ALS and FTD. In the present review, the pertinent clinical, genetic, neuropathological, neuropsychological and neuroimaging data of the literature are comprehensively and critically discussed. The distinct and overlapping features of ALS and FTD are pointed out, as well as the undisclosed questions deserving additional studies.  相似文献   
42.
Cellulose synthase-interactive protein 1 (CSI1) was identified in a two-hybrid screen for proteins that interact with cellulose synthase (CESA) isoforms involved in primary plant cell wall synthesis. CSI1 encodes a 2,150-amino acid protein that contains 10 predicted Armadillo repeats and a C2 domain. Mutations in CSI1 cause defective cell elongation in hypocotyls and roots and reduce cellulose content. CSI1 is associated with CESA complexes, and csi1 mutants affect the distribution and movement of CESA complexes in the plasma membrane.  相似文献   
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44.
High‐risk skin cancer arising on the upper limb or trunk can cause axillary nodal metastases. Previous studies have shown that axillary radiotherapy improves regional control. There is little published work on technique. Technique standardization is important in quality assurance and comparison of results especially for trials. Our technique, planned with CT assistance, is presented. To assess efficacy, an audit of patients treated in our institution over a 15‐month period was conducted. Of 24 patients treated, 13 were treated with radical intent, 11 with this technique. With a follow up of over 2 years, the technique had more than a 90% (10/11) regional control in this radical group. Both of the radical patients who were not treated according to the technique had regional failure. One case of late toxicity was found, of asymptomatic lymphoedema in a radically treated patient. This technique for axillary radiotherapy for regional control of skin cancer is acceptable in terms of disease control and toxicity as validated by audit at 2 years.  相似文献   
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46.
Inactivation of the von Hippel-Lindau (VHL) gene and activation of the hypoxia-inducible factor (HIF) in susceptible cells precedes formation of tumorlets and frank tumor in the epididymis of male VHL patients. We performed detailed histologic and molecular pathologic analysis of tumor-free epididymal tissues from VHL patients to obtain further insight into early epididymal tumorigenesis. Four epididymides from two VHL patients were serially sectioned to allow for three-dimensional visualization of morphologic changes. Areas of interest were genetically analyzed by tissue microdissection, immunohistochemistry for HIF and markers for mesonephric differentiation, and in situ hybridization for HIF downstream target vascular endothelial growth factor. Structural analysis of the epididymides revealed marked deviations from the regular anatomic structure resulting from impaired organogenesis. Selected efferent ductules were represented by disorganized mesonephric cells, and the maldeveloped mesonephric material was VHL-deficient by allelic deletion analysis. Furthermore, we observed maldeveloped mesonephric material near cystic structures, which were also VHL-deficient and were apparent derivatives of maldeveloped material. Finally, a subset of VHL-deficient cells was structurally integrated in regular efferent ductules; proliferation of intraductular VHL-deficient cells manifests itself as papillary growth into the ductular lumen. Furthermore, we clarify that that there is a pathogenetic continuum between microscopic tumorlets and formation of tumor. In multiple locations, three-dimensional reconstruction revealed papillary growth to extend deeply into ductular lumina, indicative of progression into early hamartoma-like neoplasia. We conclude epididymal tumorigenesis in VHL disease to occur in two distinct sequential steps: maldevelopment of VHL-deficient mesonephric cells, followed by neoplastic papillary proliferation.  相似文献   
47.
In a case-control study to understand the risk factors for development of life-threatening dehydration, a total of 379 children comprising 243 cases (moderate or severe dehydration) and 136 controls (non or mild dehydration) up to 2 years of age suffering from acute watery diarrhoea were studied. By univariate analysis, the presence of vibrios in stool, withdrawal of breast feeding during diarrhoea, not giving fluids, including oral rehydration solution (ORS), during diarrhoea, frequent purging (> 8/ day), vomiting (> 2/day) and undernutrition were identified as risk factors. However, by multivariate analysis after controlling for confounders, withdrawal of breast feeding during diarrhoea (odds ratio (OR) = 6.8, p < 0.00001) and not giving ORS during diarrhoea (OR = 2.1, p < 0.006) were identified as significant risk factors. The confounding variables which also contributed significantly to increasing the risk were age (≤ 12 months; OR = 2.7, p = 0.001), frequent purging (> 8/day; OR = 4.1, p < 0.00001), vomiting (> 2/day; OR = 2.4, p = 0.001) and severe undernutrition (%median <60 weight-for-age of Indian Academy of Paediatrics classification; OR = 3.1, p = 0.001). We feel that these findings will be useful for Global and National Diarrhoeal Diseases Control Programmes for formulating intervention strategies for preventing death due to diarrhoeal dehydration.  相似文献   
48.
Anti-myeloperoxidase (MPO) antibodies are associated with the development of anti-neutrophil cytoplasmic antibody (ANCA)-related vasculitis. The imbalance between the protease-antiprotease activity in the neutrophils has been implicated in the pathogenesis of ANCA-related vasculitis. Ceruloplasmin is an acute-phase protein that has antiproteinase and antioxidant properties and inhibits MPO activity. We attempted to study the association between serum ceruloplasmin and ANCA in childhood vasculitis. Forty-five ANCA-related diseases were included in the study. The age range was 4-16 years. Patients were divided into two groups based on indirect immunofluorescence and/or ELISA specificity (MPO). Twenty-six patients had p-ANCA- and 19 patients had c-ANCA-positive disease. Nine patients with Henoch-Sch?nlein purpura were studied as an ANCA-negative control group. Serum ceruloplasmin levels in p-ANCA-, c-ANCA-positive patients, and controls were 125.85+/-93.48 mg/dl, 59.79+/-17.60 mg/dl, and 64.34+/-18.77 mg/dl, respectively, and were significantly higher in patients with p-ANCA ( P<0.05). Ceruloplasmin levels were significantly decreased in remission ( P<0.05). Median MPO level in p-ANCA-positive patients was 15.2 (5-250) and was negative in all c-ANCA-positive patients. There was a significant positive correlation between MPO and ceruloplasmin levels ( r=0.70, P<0.05). Of 26 patients (53.8%) in the p-ANCA-positive group, 14 had renal involvement. The patients with renal disease had significantly higher ceruloplasmin levels than others (151.17+/-92.14 and 134.64+/-95.16 mg/dl respectively, P<0.05). In conclusion, the increase in ceruloplasmin levels during the acute phase suggests that this might be an activation criterion or a response to neutrophil-mediated tissue injury. Increased ceruloplasmin levels together with p-ANCA positivity may be predictive for renal involvement and a serious clinical course. The correlation between ceruloplasmin and MPO levels supports their association. Further studies are necessary to elucidate whether genetic and/or functional alterations in ceruloplasmin are effective in the pathogenesis of vasculitis.  相似文献   
49.
The effect of subinhibitory concentrations (1/2-1/32 x MIC) of ciprofloxacin, ofloxacin and levofloxacin on the adherence of three strains of Escherichia coli (a mannose-resistant haemagglutinating clinical isolate, a non-haemagglutinating clinical isolate and the mannose-resistant haemagglutinating ATCC 25922 strain) were studied. Ciprofloxacin had the lowest MIC values but only the 1/2 MIC concentration inhibited adherence of mannose-resistant haemagglutinating strains after exposure to subMIC values. Significant inhibition of adherence was observed with 1/4 x MIC ofloxacin for both haemagglutinating isolate (27096) and the ATCC strain. Levofloxacin might be more effective and safer than ciprofloxacin and ofloxacin as a long acting fluoroquinolone at subMIC values in patients with UTI.  相似文献   
50.
Recent studies have demonstrated that the metabolic hormones insulin and leptin can modulate behavioral performance in reward-related paradigms. However, specific anatomical substrate(s) within the CNS for these effects remain to be identified. We hypothesize that midbrain dopamine neurons, which have been implicated to be critical in the mediation of motivational and reward aspects of stimuli, contribute to these behavioral effects of insulin and leptin. As one approach to evaluate this hypothesis, we used double-labeling fluorescence immunohistochemistry to determine whether the midbrain dopamine neurons express insulin receptors or leptin receptors. Extensive co-expression of tyrosine hydroxylase (a marker for dopamine neurons) with both the insulin receptor and the leptin receptor was observed in the ventral tegmentum and substantia nigra. These findings suggest that midbrain dopamine neurons are direct targets of insulin and leptin, and that they participate in mediating the effects of these hormones on reward-seeking behavior.  相似文献   
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