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1.
Morphological and biochemical studies of a mouse mutant (fro/fro) with bone fragility. 总被引:4,自引:0,他引:4
The mutation fragilitas ossium (fro) was discovered in a random-bred stock of mice during an experiment aimed at detecting recessive lethal mutations after treatment of the postmeiotic germ cells of male mice with tris (1-aziridinyl)phosphine sulphide. The affected mice were moderately runted and had deformities in all four limbs. The radiological and histological findings indicate that the mutant is similar to human osteogenesis imperfecta. The ash content of long bones was lower in the mutant. A defect of type I collagen could not be detected. The electrophoretic patterns of alpha bands of type I and V collagen and CB derived peptides of type I collagen from bone and skin showed no abnormalities. The total collagen synthesis and secretion in cultures of dermal fibroblasts, as well as the gel electrophoresis of procollagen and collagen chains synthesized, and of their CB peptides, were the same as those found in the controls. The percentage of type I and type V collagen synthesized was similar; that of type III was lower in the mutants. Bone osteonectin was found to be decreased by 30% and bone sialoprotein by 5%. The mRNA level for osteonectin was decreased in the fibroblasts of the mutant by about 50%. Whether the defective expression of the osteonectin in fro/fro mice is due to a mutation in the gene itself or its regulatory site(s), or is secondary to other factors remains to be established. The fro/fro mouse may represent a model for some forms of human bone fragility without collagen abnormalities. 相似文献
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Muriel Mitcheson Brown 《British Journal of Psychotherapy》2006,22(4):463-470
ABSTRACT Freud's paper on the Schreber Case is considered from a contemporary perspective drawing on the object relations theorists. Some of Winnicott's ideas are used to illustrate how one might understand Schreber's predicament today. Although Freud's views on the role of repressed homosexual longings in the aetiology of Schreber's illness are not endorsed his prescience in the search for meaning in the patient's discourse is applauded. 相似文献
4.
A 79-year-old man was referred to emergency department for vagueabdominal pain. In the past, the patient had cardiac arrhythmiasnecessitating a pacemaker placement. On admission, the patienthad a normal ausculation and the abdomen examination was unremarkable.Postero-anterior chest radiograph revealed normal cardiac sizeand a small left pleural effusion. 相似文献
5.
Kevin Montgomery Michael Stephanides Stephen Schendel Muriel Ross 《Computerized medical imaging and graphics》2005,29(2-3):203-222
This paper covers work in virtual reality-based, patient-specific surgical planning over the past decade. It aims to comprehensively examine the user interface paradigms and system designs during that period of time and to objectively analyze their effectiveness for the task. The goal is to provide useful feedback on these interface and implementation paradigms to aid other researchers in this field. First, specialized systems for specific clinical use were produced with a limited set of visualization tools. Later, through collaboration with NASA, an immersive virtual environment was created to produce high-fidelity images for surgical simulation, but it underestimated the importance of collaboration. The next system, a networked, distributed virtual environment, provided immersion and collaboration, but the immersive paradigm was found to be of a disadvantage and the uniqueness of the framework unwieldy. A virtual model, workbench-style display was then created using a commercial package, but limitations of each were soon apparent. Finally, a specialized display, with an integrated visualization and simulation system is described and evaluated. Lessons learned include: surgical planning is an abstract process unlike surgical simulation; collaboration is important, as is stereo visualization; and that high-resolution preoperative images from standard viewpoints are desirable, but interaction is truly the key to planning. 相似文献
6.
Laboratory investigation: Effects of propofol on the systemic inflammatory response during aortic surgery 总被引:2,自引:0,他引:2
José M. Rodríguez-López Pilar Sánchez-Conde Francisco S. Lozano Juan L. Nicolás Francisco J. García-Criado Carlos Cascajo Clemente Muriel 《Journal canadien d'anesthésie》2006,53(7):701-710
PURPOSE: A laboratory investigation was undertaken to assess the effects of propofol on renal function, through modulation of the systemic inflammatory response, in an in vivo experimental model of aortic surgery in comparison with sevoflurane. METHODS: Twenty young male piglets were anesthetized with either propofol 4 mg.kg(-1).hr(-1) (n = 10) or sevoflurane 1.5% end-tidal concentration (n = 10). Animals were subjected to aorta-aortic bypass with suprarenal aortic clamping for 30 min. At specific intervals (basal -before the start of surgery; reperfusion 15 min after unclamping the aorta; at 24, 48 and 72 hr after surgery, and on the seventh day after surgery) the levels of the following were determined: plasma creatinine, renal myeloperoxidase, tumour necrosis factor-alpha, interleukin 1-ss, and interferon-gamma; kidney superoxide anion and its detoxifying enzyme superoxidase dismutase, kidney malondialdehyde and the activity of inducible nitric oxide synthase. Seven days after surgery, the animals were anesthetized using the described techniques, and after blood withdrawal and kidney sampling they were sacrificed. RESULTS: In comparison with sevoflurane, propofol was associated with a lower concentration of plasma creatinine (P < 0.05) together with lower concentrations of myeloperoxidase, tumour necrosis factor-alpha, interleukin 1-ss, interferon-gamma, superoxide anion and superoxidase dismutase, malondialdehyde and inducible nitric oxide synthase (P < 0.05). CONCLUSION: In an experimental model of aortic reconstructive surgery, and compared with sevoflurane, propofol anesthesia is associated with less neutrophil infiltration, lower plasma proinflammatory cytokine levels, lower production of oxygen free radicals, less lipid peroxidation, and reduced inducible nitric oxide synthase activity. These observations suggest a possible renal protective effect of propofol in this surgical setting. 相似文献
7.
Muriel Wisniewski Alain Le Borgne Nicolas Spassky 《Macromolecular chemistry and physics.》1997,198(4):1227-1238
The polymerization of lactides with various D /L enantiomeric compositions using achiral Schiff's base/aluminium methoxide as initiator (SALENAlOCH3) in dichloromethane solution at 70°C is reported. The conversion was kept below 70% in order to limit transesterification reactions. The polymers obtained after precipitation show a narrow molecular weight distribution (ratio of weight- to number-average molecular weights M w/M n = 1,1–1,2) and an optical rotation higher than that expected from the optical purity of the starting monomers. The examination of the thermal properties reveals that whatever their enantiomeric composition all the prepared polymers are crystalline. This unusual behavior is explained by an end-chain propagation mechanism producing stereocopolymers with long enantiomeric sequences, i.e., increased isotacticity as substantiated by an examination of the microstructure of the polymers by means of 13C nuclear magnetic resonance. A stereocomplex formation was observed for stereocopolymers with optical purities below 40%. 相似文献
8.
Walter Matthys MD Han De Vries MS Ankie Hectors MS Maarten Veerbeek MS Willeke Heidemann MS Muriel Goud MS Jan A. R. van Hooff PhD Herman Van Engeland MD 《Child psychiatry and human development》1995,26(1):29-41
The behavior of conduct disordered (CD) children was compared with normal control (NC) children in interaction with normal
peers. Dyads consisting of a) a CD child and a normal peer and b) an NC child and the same normal peer as in a) were observed.
CD boys were less able than NC boys to neutralize incipient conflicts. Hitherto most behavioral studies of CD boys have concentrated
on their tendency to escalate conflicts but have paid very little attention to their difficulty in neutralizing conflicts. 相似文献
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