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51.
52.
Nils Johan Nilsson 《Pflügers Archiv : European journal of physiology》1956,262(6):595-615
Ohne ZusammenfassungMit 12 Textabbildungen 相似文献
53.
Karyotypic evolution in Ph-positive chronic myeloid leukemia in relation to management and disease progression 总被引:1,自引:0,他引:1
Birgitta Swolin Aleksander Weinfeld Jan Westin Johan Waldenström Bengt Magnusson 《Cancer Genetics and Cytogenetics》1985,18(1):65-79
In a prospective study of 32 patients with chronic myeloid leukemia the frequency of chromosome abnormalities in addition to the Philadelphia chromosome (Ph) increased when the disease progressed. Before metamorphosis, 10 patients (31%) had developed additional abnormalities. Such abnormalities were present in three of them at the time of diagnosis; in the other seven, they were detected late in the chronic phase. New clonal abnormalities heralded or accompanied a more malignant phase of the disorder, usually a blastic leukemia. During metamorphosis, 78% of the patients had additional abnormalities, which in 68% of these cases comprised at least one of +8, +22q- or i(17q). Clones with additional abnormalities disappeared in eight cases, either spontaneously or in association with cytostatic therapy during the chronic or blastic phase. Involvement of chromosome #8, usually in the form of a trisomy, was found in 7 of 12 patients treated with busulfan, but was not found in any of the 10 hydroxyurea-treated patients, of whom 8 were splenectomized early during the chronic phase. Cells from the spleen, obtained by fine needle aspiration or splenectomy were cytogenetically examined in 18 cases during the chronic phase, but abnormalities in addition to the Ph were noted in only one patient, who was examined in the late chronic phase. The same abnormalities were present in bone marrow cells of this patient. 相似文献
54.
Magnesium-inhibited, TRPM6/7-like channel in cardiac myocytes: permeation of divalent cations and pH-mediated regulation 总被引:5,自引:0,他引:5
55.
Hartman EH Pikkemaat JA Vehof JW Heerschap A Jansen JA Spauwen PH 《Tissue engineering》2002,8(6):1029-1036
In animal studies of tissue engineering of bone, histology remains the standard for assessing bone formation. As longitudinal studies with this method are feasible only at the cost of large numbers of animals, we looked for an alternative. Therefore, demineralized bone matrix (DBM) and inactivated demineralized bone matrix (iDBM) implants were subcutaneously implanted in a rat. At 1, 3, 5, and 7 weeks postimplantation soft X-ray and magnetic resonance imaging (MRI) were done to monitor bone formation in the implants. At 7 weeks, the animal was killed and the implants were retrieved for histology. Our results showed that in vivo MRI is well suited to assess bone formation larger than 0.5 mm in diameter and to monitor the complete three-dimensional shape of the newly formed bone noninvasively and longitudinally. The MRI results matched well with the histology results obtained at 7 weeks. In contrast, X-ray imaging appeared inappropriate to monitor the bone formation process in DBM. 相似文献
56.
13C NMR spectroscopic studies on polyanion-polycation complexes and their component polyelectrolytes
Joachim Ktz Andreas Ebert Jürgen Kunze Burkart Philipp Johan Lindberg Kari Soljamo 《Macromolecular chemistry and physics.》1990,191(3):651-658
Position and intensities of the 13C NMR signals and relaxation times T1 of several anionic and cationic polyelectrolytes in the solid state were compared with those of the appropriate polyanion-polycation complexes. At a high charge density of the components, the most significant changes of the parameters in question due to complex formation are observed for the C atoms adjacent to the charge centers, indicating a strong Coulombic interaction. At lower charge density, conformational changes of the polymer chains have also to be taken into consideration. 相似文献
57.
58.
Molecular genetic analysis of familial early-onset Alzheimer's disease linked to chromosome 14q24.3 总被引:4,自引:2,他引:4
Cruts Marc; Backhovens Hubert; Wang Sheng-Yue; Van Gassen Geert; Theuns Jessie; De Jonghe Chris; Wehnert Anita; De Voecht Joke; De Winter Goedele; Cras Patrick; Bruyland Marc; Datson Nicole; Weissenbach Jean; Dunnen Johan T.den; Martin Jean-Jaques; Hendriks Lydia; Van Broeckhoven Christine 《Human molecular genetics》1995,4(12):2363-2371
Genetic linkage studies have indicated that chromosome 14q24.3harbours a major locus for early-onset (onset age <65 years)Alzheimer's disease (AD3). Positional cloning efforts have identifieda novel gene S182 or presenilin 1 as the AD3 gene. We have mappedS182 in the AD3 candidate region between D14S277 and D14S284defined by genetic linkage studies in the two chromosome 14linked, early-onset AD families AD/A and AD/B. We have shownthat S182 is expressed in lymphoblasts and have determined thecomplete cDNA in both brain and lymphoblasts by RT-PCR sequencing.S182 is alternatively spliced in both brain and lymphoblastswithin a putative phosphorylation site located 5' in the codingregion. We identified two novel mutations, Ile143Thr and Gly384Alalocated in, respectively, the second transmembrane domain andin the sixth hydrophilic loop of the putative transmembranestructure of S182. As families AD/A and AD/B have a very similarAD phenotype our observation of two mutations in functionallydifferent domains suggest that onset age and severity of ADmay not be very helpful predictors of the location of putativeS182 mutations. 相似文献
59.
Pierre-Paul van Bogaert Johan S. Vereecke Edward E. Carmeliet 《Pflügers Archiv : European journal of physiology》1978,375(1):45-52
- Cardiac Purkinje fibers exposed to alkaline solutions (pH 8 to 9.5) show an increase in rate of diastolic depolarization, eventually resulting in induction of spontaneous activity or an increase of the spontaneous firing rate.
- The voltage-clamp analysis of the transmembrane currents in pH 9–9.5 shows: i) a shift in the depolarizing direction of the activation (s∞) and time constants (τ s ) curve of the \(i_{{\text{K}}_{\text{2}} }\) current, ii) a small increase in the maximal value of the fully activated \(i_{{\text{K}}_{\text{2}} }\) current, iii) no significant change of background current in the pacemaker region of membrane potentials.
- The effect of NH4Cl was studied as a means to vary intracellular pH. In the presence of Tris buffer the addition of 5 mM NH4Cl resulted in i) a shift in the depolarizing direction and a decrease in slope of the activation curve of the \(i_{{\text{K}}_{\text{2}} }\) current, ii) a shift in the depolarizing direction of the time-constants curve together with an increase in the maximum value of τ s , iii) an increase in the maximum value of the fully activated \(i_{{\text{K}}_{\text{2}} }\) current and a depolarizing shift of the reversal potential, similar to the effect of addition of Kc. In the presence of CO2?HCO3 buffer the addition of NH4Cl had no significant effect on the kinetics of the \(i_{{\text{K}}_{\text{2}} }\) current. Since intracellular pH is only affected by NH4Cl in the presence of Tris buffer, the results suggest that intracellular alkalinization is responsible for the change in \(i_{{\text{K}}_{\text{2}} }\) kinetics.
- Based on the findings with NH4Cl it is suggested that perfusion with Tris buffered alkaline solutions not only affects net negative surface charges on the outside but also and to a larger extent increases negative surface charges on the inside of the cell membrane.
60.
Helin H Lundin M Lundin J Martikainen P Tammela T Helin H van der Kwast T Isola J 《Human pathology》2005,36(4):381-386
Gleason grading forms the basis of prognostic and therapeutic assessment in prostatic carcinoma despite its subjective nature and substantial interobserver variation. The accuracy of Gleason grading can be improved by the use of educational tools such as reference images. However, conventional microscopy images are of limited educational value because it is neither possible to view the sample at different magnifications nor to navigate into different areas of the specimen. This limitation can be overcome by the use of virtual microscopy, which allows viewing entire digitized microscope slides. We created an interactive Web site ( www.webmicroscope.net/gleason ) featuring a comprehensive set of prostatic needle biopsies as virtual slides, which can be viewed with a standard Web browser (Internet Explorer or Netscape). To evaluate the validity of Web-based virtual microscopy for Gleason grading, an experienced uropathologist (TK) scored a series of 62 biopsies from the original glass slides and 6 weeks later from virtual slides on the Web site using an ordinary desktop computer. The intraobserver agreement was excellent, with identical Gleason scores found in 48 of the 62 cases ( kappa = 0.73). The 14 remaining scores differed only by 1 point on the Gleason scale (2-10). The virtual slides were viewed by 2 other uropathologists (PM and HH), with interobserver kappa coefficients ranging from 0.55 to 0.62, which is within the range of previously reported studies using glass slides. The 3 uropathologists' Gleason scores were included as reference scores on the Web site, which now serves as a publicly open platform for self-testing and learning of Gleason grading. We conclude that Web-based virtual microscopy is a promising new tool for teaching and standardizing Gleason grading. 相似文献