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11.
OP Rosaeg M Bell NJ Cicutti KC Dennehy AC Lui B Krepski 《Canadian Metallurgical Quarterly》1998,23(6):575-579
BACKGROUND: The main purpose of the reconstruction of the cranium is the protection of the brain. Besides we have to consider important functional and aesthetic necessities in order to achieve satisfactory results. METHODS: Thirty-six clinical cases, operated from November 1991 to June 1996, in which the reconstruction of the cranial vault is carried out by a polymethylmethacrylate acrylic resin are analysed. The causes and locations of the most common bone defects and the main indications for reconstruction are examined. While the repair of the osseous gaps caused by neoplasms is immediate, in the traumatic occurrences, in order to reduce the probability of infectious complications, an average time of 11 months elapsed from the first operation. The surgical technique, with slightest alterations, is the same in all the presented cases, preparing the acrylic resin straight on the operating table. The resin, moulded and adapted to the defect until its complete hardening, presents, thanks to its properties, manifold advantages (and few real disadvantages). RESULTS: The results, in terms of complications, are very satisfactory, with an infectious rate of 2.7%. Besides, in one third of the patients, a considerable clinical improvement after the repair has been observed. CONCLUSIONS: According to personal experience, it is possible to affirm that polymethylmethacrylate, with its remarkable plasticity and stability in time, can always guarantee a satisfactory functional and aesthetic result. 相似文献
12.
We have determined the nucleotide and encoded amino acid sequences of the capsid, membrane precursor, membrane, envelope, and nonstructural NS1 protein genes of a dengue-2 virus (D2-04) isolated from a patient in Hainan, China. The sequenced region contains a gene organization similar to that of other flaviviruses. The overall amino acid sequence similarity between D2-04 and other dengue-2 viruses is greater than 92%, whereas that between D2-04 and members of the other dengue serotypes is about 65%. 相似文献
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The uncorrected cumulative five-year survival rate ("actuarial method") among 195 patients with infiltrative malignant melanoma of the skin was 58% (160 cases) in clinical stage I, 26% (35 cases) in clinical stage II. In addition to clinical staging, microstaging - i.e. the histologically determined depth of invasion of the primary tumour - is of great prognostic significance. In microstages 2 and 3 with the largest vertical tumour diameter below 0.76 mm, five-year survival rate was 100% while in microstage 3 with greater vertical tumour diameter it was 66% in microstage 4 55% and microstage 5 31%. Results of treatment can be reliably interpreted only if they are divided according to microstage. Propylactic dissection of the regional lymph-nodes (dissection in clinical stage I) need not be undertaken in microstages 2 and 3 with vertical tumours diameter below 0.76 mm. Whether prophylactic dissection was done in one or two sessions has apprarently no significant influence on survival rate. A single X-radiation dose to the primary tumour of 4 000 -6000 R immediately before excision of the tumour did not significantly increase the results. The results were particularly bad when the primary tumour was removed after inadequate manipulation. 相似文献
16.
In the present work, sealant compounds based on MO-BaO-SiO2 (where MO is MgO, CaO, and SrO) were synthesized. These materials are used for manufacture of electrochemical devices with
solid electrolytes. The sealant properties such as the temperature coefficient of linear expansion, softening temperature,
and temperature of electrolyte wetting were studied, and X-ray diffraction analysis of the samples was carried out.
Original Russian Text ? V.P. Ishchuk, M.V. Glumov, A.K. Demin, 2009, published in Neorganicheskie Materialy, 2009, Vol. 45,
No. 4, pp. 492–495. 相似文献
17.
H Peltola I Davidkin M Valle M Paunio T Hovi OP Heinonen P Leinikki 《Canadian Metallurgical Quarterly》1997,350(9088):1364-1365
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The fluorescent probe Prodan has been widely used as a probe of model and biological membranes. Its fluorescent maxima in phospholipid bilayers vary as a function of phase state, with maxima at 485 for the liquid crystal Lalpha, 435 nm for the gel L'beta, and 507 nm for the interdigitated gel LbetaI phase, with excitation at 359 nm. These spectral changes have been used for the detection of phase changes among these phases. In the present study, the fluorescent properties and partition coefficients of Prodan in model membranes of phosphatidylcholines and phosphatidylethanols have been studied as a function of lipid phase state and cholesterol content. It is shown that the Prodan spectrum in the presence of cholesterol no longer reflects the known phase state of the lipid; in each phase state, the presence of cholesterol leads to a spectrum with the maximum at 435 nm, characteristic of the noninterdigitated gel phase. The partition coefficient of Prodan into these lipids also varies with the phase state, giving values of 0.35 x 10(4) in the interdigitated gel, 1.8 x 10(4) in the noninterdigitated gel, and 7. 6 x 10(4) in the liquid crystal phase. In the presence of cholesterol these partition coefficients are increased to 13 x 10(4) for the liquid crystal and the gel phase, and 5.1 x 10(4) in the presence of 100 mg/ml ethanol. These results suggest that Prodan has preferential interactions with cholesterol, and is thus not a randomly distributed fluorescent reporter probe in membranes containing cholesterol. These results suggest that Prodan should be used only with great caution in complex lipid mixtures, particularly biological membranes. 相似文献