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31.
Benign symmetric lipomatosis (BSL), also known as Madelung's disease, is a rare condition and characterized by diffuse but painless growth of unencapsulated lipomas. A close correlation to alcohol and nicotine abuse, metabolic disturbances and malignant tumours have been observed. Surgical treatment is frequently followed by recurrence, nevertheless, it can yield satisfactory functional and cosmetic results. A case of BSL with uncommonly distributed tumors is reported. 相似文献
32.
We have tested the effect of several bile acids on the proliferation and differentiation of the HL60 human promyelocytic leukemia cell line in vitro. Deoxycholate, chenodeoxycholate and lithocholic acid caused dose-dependent inhibition of cell proliferation and induction of differentiation along the monocyte/macrophage pathway as determined by morphology, NBT test, non-specific esterase, and staining by monoclonal antibodies against specific cell-surface antigens. Optimal effects were obtained at 100, 75, and 60 microM of the 3 bile acids respectively. Cell-cycle flow-cytometric analysis showed that a substantial fraction of HL60 cells accumulated at the G0/G1 transition. Protein-kinase-C inhibitors such as sphinganine and H-7 inhibited the differentiation-inducing effect of bile acids, suggesting a possible role for PKC in this regulation. When bile acids were combined with non-effective concentrations of all-trans retinoic acid, enhancement of the monocytic differentiation of THP-1 human leukemia cells was observed. Our findings demonstrate induction of tumor-cell differentiation by bile acids, compounds that present minimal undesirable effects in humans. 相似文献
33.
The degradation of interlaminar shear strength and shear fracture toughness of glass/epoxy composites due to uptake of distilled water and sea water has been studied. The composites were immersed in water for up to eight months at temperatures up to 70 °C. Unreinforced matrix resin samples were also immersed for periods up to 2 years. Sea water was absorbed less rapidly than distilled water. Weight gains below 1% did not influence the shear strength while higher weight gains reduced shear strength up to 25%. The loss in apparent interlaminar shear strength was uniquely related to specimen weight gain. Mode II fracture toughness, G
IIc, also decreased with increasing immersion time after an initial incubation period, but the accelerated tests were found to reduce G
IIc less than the room temperature tests at comparable weight gains. 相似文献
34.
G Nadali EA de Wynter F Perandin L Tavecchia C Vincenzi A Ambrosetti M Fornalè G Perona G Pizzolo NG Testa 《Canadian Metallurgical Quarterly》1998,83(12):1059-1065
BACKGROUND AND OBJECTIVE: Long-term culture-initiating cells (LTC-IC) are the best available approximation to an in vitro assay of stem cells in humans although they still represent a heterogeneous population in terms of proliferative capacity and sensitivity to different growth factors. Human umbilical cord blood (CB) is rich in hemopoietic progenitor cells, as measured by clonogenic assays and contains stem cells capable of reconstituting the marrow after ablation in clinical transplantation. We evaluated the influence of culture conditions on the in vitro behavior of LTC-IC from CB. DESIGN AND METHODS: LTC-IC were evaluated in long-term cultures, comparing two types of murine stromal cell lines: M2-10B4 and M2-10B4 transfected with cDNAs for human G-CSF and IL-3. RESULTS: Two and five fold higher numbers of terminally differentiated cells were produced during nine weeks of culture of CB mononuclear or CD34+ cells respectively, in cultures containing a M2-10B4 IL-3 G-CSF cell line compared to cultures containing the parental cell line. Likewise, a higher number of colony-forming cells (CFC) were detected in the supernatant of cultures with the transfected cell line. In contrast, the number of CFC generated within the stromal layer, after 5 or 9 weeks of culture, was significantly higher in cultures on M2-10B4 cells than those on M2-10B4 IL-3 G-CSF. INTERPRETATION AND CONCLUSIONS: Our results show that the proliferative capacity of CB LTC-IC can be strongly influenced by culture conditions and that the frequency of LTC-IC estimated using these cell lines as stromal support is not identical. 相似文献
35.
Castagna Claudia; Absil Philippe; Foidart Agnès; Balthazart Jacques 《Canadian Metallurgical Quarterly》1998,112(1):233
The authors investigated the behavioral actions of vasotocin (VT) in castrated testosterone-treated male Japanese quail. The appetitive and consummatory components of sexual behavior as well as the occurrence frequency of crows were inhibited, in a dose-dependent manner, by injections of VT. The authors observed opposite effects after injection of the V1 receptor antagonist, dPTyr(Me)AVP. Lower doses of VT were more active after central than after systemic injection, and effects of systemic injections of VT were blocked by a central injection of dPTyr(Me)AVP. The behavioral inhibition was associated with a modified diuresis after systemic but not central injection. These results provide direct evidence that VT affects male sexual behavior in quail by a direct action on the brain independent of its peripheral action on diuresis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Asendorpf Jens B.; Warkentin Veronique; Baudonnière Pierre-Marie 《Canadian Metallurgical Quarterly》1996,32(2):313
Eighteen-month-old children were tested for mirror self-recognition using the classic rouge test or an alternative procedure, for social contingency awareness by being closely imitated for a long time, and for the capacity for communication by synchronic imitation. The classic mirror rouge test was shown to produce false negatives. Most recognizers and nonrecognizers became aware of being imitated and imitated the activity of a model, but only recognizers engaged in sustained synchronic imitation of the model. The results support our hypothesis that self-recognition and spontaneous perspective-taking develop in close synchrony because both require a capacity for secondary representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
Cerebral palsy (CP) is classified as a static encephalopathy. CP is a nonprogressive disorder affecting posture and movement and is commonly associated with a spectrum of developmental disabilities. Serial testing of physiological function can provide a quantitative assessment of improvement or decline in the condition of the patient. Furthermore, there are increasing numbers of children with disability who are involved in athletic activity, and the need for physiological feedback to the disabled athlete and coach is the same as for able-bodied individuals. It is acknowledged that children and adolescents with CP have a lower maximal oxygen consumption (VO2max) compared with their able-bodied peers. Children with CP also have distinctly subnormal values for peak anaerobic power and muscular endurance of the upper and lower limbs. Irrespective of the scaling method used (absolute or relative), when compared with normal data from healthy controls, children with CP scored between 2 and 4 standard deviations below the expected mean value for power. Gait abnormalities in children with CP have been shown to increase submaximal walking energy expenditure almost 3-fold compared with healthy children. Assessment of the metabolic cost alone is important but does not provide any information on the mechanisms giving rise to the high energy cost of locomotion in children with CP. Hence, a multidisciplinary (kinetic, kinematic and electromyographic) approach is an important noninvasive tool for studying some of the underlying mechanisms responsible for abnormal gait and elevated energy costs. A certain level of muscle co-contraction is necessary for achieving joint stability during locomotion, particularly at the ankle and knee. There appears, however, to be a co-contraction threshold beyond which there are associated elevated metabolic costs during locomotion in children with CP. 相似文献
38.
S Ronsseray M Lehmann D Nouaud D Anxolabéhère 《Canadian Metallurgical Quarterly》1996,143(4):1663-1674
Genetic recombination was used in Drosophila melanogaster to isolate P elements, inserted at the telomeres of X chromosomes (cytological site IA) from natural populations, in a genetic background devoid of other P elements. We show that complete maternally inherited P repression in the germline (P cytotype) can be elicited by only two autonomous P elements at 1A and that a single element at this site has partial regulatory properties. The analysis of the surrounding chromosomal regions of the P elements at 1A shows that in all cases these elements are flanked by Telomeric Associated Sequences, tandemly repetitive noncoding sequences that have properties of heterochromatin. In addition, we show that the regulatory properties of P elements at 1A can be inhibited by some of the mutant alleles of the Su(var)205 gene and by a deficiency of this gene. However, the regulatory properties of reference P strains (Harwich and Texas 007) are not impaired by Su(var)205 mutations. Su(var)205 encodes Heterochromatin Protein 1 (HP1). These results suggest that the HP1 dosage effect on the P element properties is site-dependent and could involve the structure of the chromatin. 相似文献
39.
A Nobrega A Grandien M Haury L Hecker E Malanchère A Coutinho 《Canadian Metallurgical Quarterly》1998,28(4):1204-1215
Our objective was to determine the effect of level and chemical form of dietary selenium on productivity of beef cows, concentrations of triiodothyronine (T3), and thyroxine (T4) in plasma, and immunoglobulins (IgG and IgM) in plasma and colostrum of cows. Pregnant cows (n = 60) were randomly allocated among four dietary treatments of 20, 60, or 120 ppm Se as selenite and 60 ppm as selenomethionine from selenized yeast (SeY) in salts offered free-choice. Treatments began 90 d prepartum and continued through the second parturition. Treatments did not affect the final body weights of cows or birth weights or weaning weights of calves. At parturition, cows given salt with 20 ppm Se as selenite had lower (P < . 05) concentrations of Se in blood than cows with access to higher-Se salts. Treatments affected (P < .01) the concentration of T3 and the ratio of T3:T4 in plasma of cows. The concentration of T3 in plasma of cows with access to salt with 20 ppm Se was 14% lower than that in cows supplemented with 60 ppm Se as selenite or SeY. Plasma IgG in cows and calves, colostrum, and Se concentrations in colostrum, casein, and whey were lowest (P < .01) for cows given salt with only 20 ppm Se. Thus, salts with concentrations of 60 and 120 ppm Se improved measures of Se status in cows and calves. Consideration should be given to the concentrations of T3 and IgG when determining the nutritional requirements for Se in cattle. 相似文献
40.