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The light- and electron-microscopic changes in a biopsy of the liver obtained at age 17 mo from a child with fetal alcohol syndrome were studied. At the time of biopsy, hepatomegaly and raised serum transaminases were present as well as neurologic and growth defects and the typical facial anomalies seen in this syndrome. Light microscopy of the liver biopsy specimen revealed parenchymal fat with portal and perisinusoidal fibrosis. Ultrastructurally, perisinusoidal spaces contained deposits of intermediate-size and large collagen fibers, myofibroblasts and occasional Ito cells, and subendothelial basement membrane-like material. These changes resemble those seen in adult human and baboon alcoholic liver disease and suggest that hepatic fibrosis in fetal alcohol syndrome has a similar pathogenesis.  相似文献   
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Introduction Heparin sulfate (HS) has long been implicated in the bone deformity hereditary multiple exostoses (HME), and it is now clear that HME is associated with mutations in the HS biosynthetic genes EXT1 and EXT2. Interestingly, HME is also associated with an increased risk of chondro‐ and osteo‐sarcomas. Methods and results Preliminary analysis of GAG samples purified from fibroblasts of both HME and isolated non‐HME exostoses patients reveal a dramatic shift in the ratio of CS : HS, with the HME and isolated cases having a much higher proportion of CS relative to normal controls. This is true in the case of both shed and cell surface material but is far more extreme in the latter, with the HS reducing from approximately 45% in the controls to less than 10% in HME patients. Initial analysis also reveals shortened chain length within these samples; indeed they often have two populations of chains present. Simple analysis of the total disaccharide composition of these samples demonstrates no significant differences against controls. However, detailed analysis of the subpopulations of chains (as determined by chain length) within these samples as well as cartilaginous samples from exostoses patients may provide further insight into the changes that occur within the biosynthetic pathway following disrupted EXT function. We are also carrying out immunocytochemistry with a variety of HS‐specific antibodies with the aim to further investigate normal HS structure and localization. This is being carried out on human primary chondrocytes isolated from normal patients and also adult mesenchymal stem cells as they undergo differentiation into chondrocytes. HS has been identified in both these cell types, and it is hoped that the manipulation of these cells through RNAi of different enzymes of the HS biosynthetic pathway will provide a suitable model for studying what changes may occur in cellular HS structures over the initial differentiation process in the growth plate. Discussion Together, these investigations should provide a good model to allow us to determine the role of HS in chondrocyte differentiation and maturation in both normal and diseased states.  相似文献   
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Introduction:  Occupational contact dermatitis (OCD) is very common in the printing industry due to contact with chemicals, paper, and wet work. It can be avoided by adequate protective measures, but the effectiveness of intervention depends heavily on the employer's and employee's awareness of this health risk.
Objectives:  The study aimed to collect information on the knowledge, attitudes and beliefs of print workers about the risk of OCD and methods of prevention.
Methods:  A series of focus groups were held with print workers, health and safety officers and managers to discuss their awareness of dermal risk factors, risk behaviour at work, attitudes to health and safety and options on possible preventive measures. A number of companies were also visited to observe, overtly and covertly, the normal work practices.
Results:  OCD was not perceived to be either a major problem or a health and safety priority. There was general agreement about the processes and work practices that could cause skin problems. However, work practices varied considerably and did not always reflect this awareness. There was general concern about the type and availability of personal protective equipment, especially gloves and after‐work skin cream. The provision of an occupational health service was generally felt to be inadequate, and no company had a policy in place that specifically addressed skin care.
Conclusions:  These findings highlight the urgency to intensify health and safety education on skin care within the printing industry. Recommendations were developed for the evaluation of a series of risk reduction strategies.  相似文献   
6.
The dietary intake of homeless males sleeping rough in Central London   总被引:1,自引:0,他引:1  
Data concerning the food and beverage intake (including alcohol) of 79 males, aged 19–50 years, sleeping rough in Central London, who did not appear to be under the influence of drink, drugs or suffering from mental illness were collected by prompted 24-h recall and food-frequency questionnaire (FFQ). The source of food was noted and the subjects were asked about food availability and food needs. The group had intakes significantly lower than Dietary Reference Values (DRV) for the UK for energy, carbohydrate, non-starch polysaccharides (NSP), folate, zinc and magnesium. Significantly higher values were seen for protein, fat, vitamin B12, calcium and iron. Alcohol intake was higher than that assumed to approximate current intakes of the UK population. Mean macronutrient intakes for the group were similar to means for British adult men (OPCS, 1990), only protein and NSP were significantly lower. The FFQ showed very low consumption/week of fruit, vegetables, salad, fruit juice and wholewheat/brown products. Organized charities provided the major source of food energy for the group as a whole. Self-supplied sources provided the major source of total energy. It is suggested that the group may benefit from an increase in dietary fibre and energy, with an increase in the proportion of energy supplied by carbohydrate and a reduction in energy from fat and alcohol. A varied supply of food and hot meals during weekends as well as during the week may benefit the group both aesthetically and nutritionally. It may be advisable to increase the supply of wholemeal/brown bread, fruits, vegetables and salad foods without decreasing the energy content of the food available.  相似文献   
7.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
8.
Hydrolysis of peptides within lumen of small intestine   总被引:2,自引:0,他引:2  
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9.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation  相似文献   
10.
Differential pattern of DNA-aneuploidy in human malignancies   总被引:5,自引:0,他引:5  
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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