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A 51 year old man presented in 1969 with slowly progressive cerebellar ataxia of unknown origin. He was admitted to hospital aged 68 after a fall, and a ruptured spleen was removed at laparotomy. Histological analysis of the spleen suggested Niemann-Pick disease, which was subsequently confirmed. He deteriorated and died of bronchopneumonia shortly afterwards: subdural haemorrhage with storage material in neurones was found at necropsy. This late onset case of Niemann-Pick disease with neurovisceral storage is unusual and may represent a variant.  相似文献   
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Thirteen complementary DNA (cDNA) probes were used to detect the presence of foot-and-mouth disease virus (FMDV) RNA extracted from cell cultures. When labelled with 32P, these probes enabled the detection of 1 pg of FMDV-RNA, or 1 virus copy per cell. Two FMDV A12 probes that coded for the leader, structural protein VP1 region and part of the polymerase gene respectively, showed no hybridization with other closely related picornaviruses. Differentiation between FMDV serotypes A, O and C was possible, using cDNA probes from individual serotypes that corresponded to structural protein VP1.  相似文献   
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The amyloid beta precursor protein can exist as both a membrane-bound and a secreted protein, with the former having the potential to generate the amyloid beta peptide present in the neuritic plaques which are characteristic of Alzheimer's disease. In this study, we have used a clone of the AtT20 mouse pituitary cell line which expresses high levels of the amyloid beta precursor protein to characterize the glycosylation state of the secreted and membrane-bound forms of the protein and to examine the role of post-translational modifications in protein processing. Lectin blot analysis of immunoprecipitated amyloid beta precursor protein demonstrated that the soluble form of the protein contains significant amounts of sialic acid, with the lectin staining being reduced in the particulate cellular fractions. Treatment of the cells with mannosidase inhibitors to interfere with the formation of complex-type N-linked glycans resulted in a decrease in secreted amyloid beta precursor protein and an increase in the level of the cellular form of the protein. The increase in amyloid beta precursor protein levels in the cellular fraction was accompanied by an increase in perinuclear staining. Furthermore, cells overexpressing the alpha2,6(N)-sialyltransferase enzyme also demonstrated an increase in amyloid beta precursor protein secretion. These results suggest that the presence of terminal sialic acid residues on complex-type N-glycans may be required for the optimal transport of the amyloid beta precursor protein from the Golgi to the cell membrane with the subsequent cleavage to generate the secreted form of the protein.  相似文献   
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自1994年以来,我院采用改良的尿道拖人术治疗外伤性后尿道狭窄22例,取得满意疗效,现报道如下。l临床资料本组病例均为男性,为严重车祸伤或高处跌伤致骨盆骨折所致,年龄则一46岁,平均35岁。临床症状有尿道四溢血、尿摊留、腹胀、肛周青紫肿胀,有休克者2例,合并直肠损伤2例,磅眈破裂6例。术中发现前列腺尖游离者4例。所有病例不能将导尿管插入膀跳,而均行单纯“耻骨上膀胜造疾术”,有膀脱破裂者行“膀脱破裂修补术”,有直肠损伤者,行“乙状结肠造疫术”。患者于术后3-6个月来院行尿道重建术。术前常规尿道造影,显示膜部尿道狭…  相似文献   
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BACKGROUND AND PURPOSE OF THE STUDY: To compare the level of post-operative care requested for surgical patients with that provided in a Scottish teaching hospital. METHODS: A three months pragmatic prospective observational study was undertaken which included patients undergoing major surgery excluding gynaecological and elective orthopaedic surgery. A study specific questionnaire was used to collate the information. The data were inputted to DataEase 4.5 and subsequently exported to SPSSWIN version 6.1.3 for analysis. The main outcome measure was the level of care requested and the level of care actually received. MAIN FINDINGS: Among 1363 patients a total of 1395 operations were performed. The median age was 59 years with a male: female ratio of 1.1:1. The type of admission was elective in 58% and emergency in 42% of cases. The operations were elective in 44% and nonelective in 56% of cases. The ASA score was 3 or greater in 33% of patients. The optimum level of care requested by surgeons and anaesthetists was intensive therapy unit (ITU) in 9.7% and high dependency unit (HDU) in 23.6% of patients. Twenty-one (15.9%) of 132 ITU requests and 256 (73.8%) of 349 HDU requests were not met immediately post-operatively. Overall mortality was 1.5%. For those patients who received optimum requested care mortality was 1.2% and, in those patients who did not receive optimum requested care, mortality was 3.1% (p < 0.038: Chi-square). CONCLUSION: This study confirms a significant lack of access to properly staffed and equipped HDU facilities in a major teaching hospital with a consequent increase in mortality in those not receiving optimal post-operative care.  相似文献   
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Updating working memory for words: a PET activation study   总被引:2,自引:0,他引:2  
A PET study of 10 normal individuals was carried out to investigate the cerebral regions involved in the controlled updating of verbal working memory. Subjects viewed single concrete words on a computer monitor and detected occasional target words in an attended color. In the activating condition, a target was defined as a word that was identical to the previous word presented in the attended color. In the control condition, the target was a predesignated word. The same word lists, target probabilities, and target response demands were used for both conditions, with interword intervals constrained to ensure equivalence in the demand for target rehearsal. A comparison of the conditions found bilateral activation of dorsolateral prefrontal (middle frontal gyrus; MFG) and inferior parietal (supramarginal gyrus; SMG) cortical regions. Activation of the MFG is taken to reflect executive control by prefrontal regions over the working memory updating process linking posterior representations of the anticipated target stimulus to anterior representations of the planned response. It is proposed that the updating of the stimulus link is mediated via connections between the MFG and SMG. The role of the SMG as an amodal region binding the various modal representations in posterior association cortex of the word being retained in working memory is considered and reviewed. It is suggested that the combined activation of these regions is related to the executive control of goal-setting in planned behavior.  相似文献   
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Hazard RG  Reid S  Haugh LD  McFarlane G 《Spine》2000,25(11):1419-1423
STUDY DESIGN: Randomized controlled trial. OBJECTIVE: To test the ability of an educational pamphlet to improve recovery in terms of pain, work status, and health care utilization after occupational low back injury. BACKGROUND: Low back pain and disability persist as occupational health problems of epidemic proportions. Because interventions based on biomechanical models have had limited impact, recent educational approaches to preventing back problems have stressed psychosocial recovery issues. METHODS: A pamphlet was developed by compiling activity resumption, self-care, and attitudinal advice from recent publications. The pamphlet was sent at random to half of all consenting workers reporting back pain within 11 days of occupational injury between 7/96 and 6/97. Three and 6 months later, back pain, work status, health care use, and pamphlet impact outcomes were assessed through structured telephone interviews. RESULTS: Of the 726 eligible workers, 486 consented to participate. Consenters and nonconsenters and intervention and control groups were similar in initial demographic variables. The pamphlet had no statistically significant impact at the 0.05 significance level on pain severity or reduction, health care visits, or work absence. Of the 229 pamphlet recipients, 129 thought it had provided useful information, but only 25 thought it had helped them return to work more quickly. CONCLUSIONS: In this trial, a pamphlet stressing psychosocial recovery issues did not prevent or reduce postinjury pain, health care use, or work absence.  相似文献   
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