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981.
982.
J Baulieux M Adham E Oussoultzoglou E De la Roche N Berthoux O Bourdeix C Ducerf 《Canadian Metallurgical Quarterly》1998,123(5):438-444
Collagenase-1 (C1) is the predominant matrix metalloproteinase present in newly formed microvessels and serves as a marker of neovascularization. The expression of the oncofetal fragment of fibronectin (Fn-f) was found to be increased during angiogenesis. In the present study, we investigated the relationship between the expression of collagenase-1 and the oncofetal fragment of fibronectin in newly formed microvessels as markers of tumor angiogenesis. In aggressive skin tumors (i.e., morpheaform and recurrent basal cell carcinomas) and squamous cell carcinomas, neovascularization was associated with a marked increase in the number of C1-positive and Fn-f-positive microvessels. At the beginning of elongation, microvessels begin to produce C1 but lose their ability to express type IV collagen and FVIII-related antigen. Later, this endothelium produces both Fn-f and C1. As maturation of microvessels occurs, C1-containing endothelium fails to express Fn-f but begins to produce a type IV collagen-containing basement membrane and FVIII-related antigen. These studies show that there is a selective expression of both Fn-f and collagenase by immature endothelial cells. C1 production begins at early stages of blood vessel formation and continues throughout angiogenesis. In contrast, Fn-f expression is limited to later stages of vasculogenesis, indicating that these proteins are reliable markers of angiogenesis. 相似文献
983.
V. V. Afrosimov E. K. Gol’man R. N. Il’in M. N. Panov D. A. Plotkin S. V. Razumov V. I. Sakharov I. T. Serenkov A. V. Tumarkin 《Technical Physics Letters》1998,24(1):41-42
Superconducting YBa2Cu3O7−x
films were prepared by magnetron sputtering on Al2O3 single crystals with a CeO2 sublayer. Scattering of moderate-energy ions and x-ray diffraction were used to show that the films exhibit good single-crystal
properties over the entire thickness up to 2.6 μm. The hypothesis is advanced that the indentations formed by the growth of films above “extraneous” phase grains may act
as defect sinks.
Pis’ma Zh. Tekh. Fiz. 24, 91–95 (January 12, 1998) 相似文献
984.
W Zorzi O Thellin B Coumans F Melot G Hennen B Lakaye A Igout E Heinen 《Canadian Metallurgical Quarterly》1998,19(4):269-277
Thrombopoietin (TPO) or Mpl ligand is the primary physiological regulator of platelet production. This cytokine is the most potent stimulator of the proliferation and differentiation of MK progenitor and precursor cells in vitro. It also acts additively or synergistically with several cytokines on progenitor cells from various hematopoietic lineages, including the primitive stem cells. The factor is an extremely potent thrombocytopoietic agent when administrated to normal animals, and it accelerates platelet and erythropoietic recovery in several models of myelosuppression. Phase I/II clinical trials are ongoing with no detectable adverse effects. Mpl ligand does not induce platelet aggregation, but it lowers the platelet sensitivity to physiological dose of agonists. In experimental mouse models, high and chronic dose of Mpl ligand results in myelofibrosis. TPO is constantly produced by the liver and the kidney; its plasmatic clearance occurs by binding to its receptor expressed on megakaryocytes and platelets. However, the full spectrum of the biological effects of this new cytokine is not fully understood, in particular its the role in the terminal stage of platelet production. In the near future, it is likely that new insights will be obtained in the physiopathological mechanisms underlying abnormal platelet production in human. 相似文献
985.
A. A. Andronov I. A. Grishin V. A. Gur’ev V. V. Orekhovskii A. P. Savikin 《Technical Physics Letters》1998,24(5):365-366
In fluorozirconate glasses the luminescence yield of Er
2
3+
ions on the 4
I
13/2–4
I
15/2 lasing transition was increased more than tenfold by additional doping with Yb3+ and Tb3+ ions.
Pis’ma Zh. Tekh. Fiz. 24, 81–85 (May 12, 1998) 相似文献
986.
F Velardi A Di Chirico C Di Rocco C Fundarò O Genovese C Rendeli G Menichella R Serafini M Piastra L Viola D Pietrini A Pusateri F Stoppa 《Canadian Metallurgical Quarterly》1998,14(12):732-9; discussion 740-1
The authors describe the results obtained in 13 consecutive cases of craniosynostosis operated on according to a protocol devised at avoiding allogeneic blood transfusion. The protocol is based on pre- and postoperative treatment with erythropoietin, preoperative autologous blood donation, preoperative normovolemic hemodilution and intraoperative blood salvage. Nine subjects were affected by simple forms of craniosynostosis, whereas the remaining 4 presented with oxycephaly or craniofacial syndromes. Five of the 13 children were under 7 months and a further 3, under 10 months of age at the time of the surgical operation. Seven children weighed less than 10 kg. Allogeneic blood transfusion was avoided in 11 of the 13 children considered. Two failures - defined as the necessity to reinfuse the patient with an allogeneic blood transfusion - were recorded, 1 of them resulting from an unexpected hemorrhage during surgery. The results obtained indicate that this protocol designed to avoid allogeneic blood transfusion can be safely applied in the great majority of children with craniosynostosis, even when the surgical correction is carried out early in life. 相似文献
987.
The Wiener-Hopf technique is used to compute the electrostatic field distribution in an interdigital transducer at the plane interface between two dielectric media sandwiched between two grounded metallic plates, with two grounded semi-infinite neighboring plates at the interface on each side of the transducer. To this end, the associated Green's function, which already satisfies the boundary conditions at all the grounded plates, is computed. The Green's function is used to derive the elements of the charge-potential-interrelation matrix for various basis and testing functions for a method-of-moments application. Examples demonstrate that the method has considerable advantages with respect to accuracy and computer-memory requirements 相似文献
988.
T. A. Bykhovskaya K. P. Zakharova T. T. Karpova O. L. Masanov A. A. Orlova O. M. Khimchenko 《Atomic Energy》1995,79(3):606-608
Main Science Center of the Russian Federation, A. A. Bochvara All-Russia Scientific-Research Institute of Standardization
in Machine Engineering. Atomnaya énergiya, Vol. 79, No. 3, pp. 197–200, September, 1995. 相似文献
989.
In an infertility treatment programme for spinal-cord injured men, vibrator application was primarily used in cases of upper motor neurone lesion and electroejaculation in men with lower lesions, or when vibrator application failed to induce ejaculation. Spermatozoa were obtained by these methods from 29 out of 35 men who desired infertility treatment. No ejaculate was obtained from six men. Three of these men plus two others with very poor sperm quality with electroejaculation underwent micro-surgical sperm aspiration from the vas deferens for invitro fertilization (IVF), and spermatozoa were obtained from all of them. Thus it was possible to obtain spermatozoa from almost every spinal-cord injured man who had ongoing spermatogenesis using these three methods. Insemination was the primary infertility treatment used with all the couples where there was successful ejaculation. In all, 12 pregnancies resulted from home vaginal inseminations, eight from intrauterine inseminations, two from IVF with ejaculated spermatozoa, and two from IVF with spermatozoa aspirated from the vas. Three couples had children from donor inseminations (not counted in the results); 12 are still in the programme. From 24 pregnancies, 22 children have now been born to 18 couples out of the original 35 (51%), and there were four abortions. Hence, overall, infertility treatment of spinal-cord injured men has given good results. 相似文献
990.
D Sch?fer O Bianchi W Greulich C Sch?fer T Sch?fer ME Schl?fke 《Canadian Metallurgical Quarterly》1996,146(13-14):296-298
Most information about the structures within the brain stem that modulate respiration and sleep are gathered from animal experiments. Therefore we examined 10 patients several weeks after an infarction of the brain stem by means of polysomnography and tested the chemosensitive drives of respiration. None of these patients complained about symptoms of sleep disordered breathing. In each case polysomnographic measurements and ventilatory response curves revealed pathologic findings. The respiratory response to CO2 was diminished or completely abolished in each patient. In some cases hypoventilation or disturbances of the respiratory rhythmicity could be seen. In several cases missing REM sleep, sleep fragmentation or the reduction of slow wave sleep were observed. The study indicates that on the base of results from animal research the comparison of morphological and pathophysiological data is helpful to gain a better understanding on the coupling of the respiratory system with sleep at the brain stem level as well as on the pathomechanism of sleep related breathing disorder. 相似文献