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81.
W. Schröter E. Schulz R. Bonn 《Journal of molecular medicine (Berlin, Germany)》1970,48(16):1013-1014
Zusammenfassung Bei 16 von 17 Patienten mit Osteomyelofibrose wurden in den Erythrocyten erhöhte Konzentrationen an reduziertem Glutathion nachgewiesen. Die Bestimmung des Glutathions kann als differentialdiagnostisch wertvolles Kriterium für die Charakterisierung der Osteomyelofibrose angesehen werden.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
Summary In 16 of 17 patients with osteomyelofibrosis the concentration of erythrocyte reduced glutathione was increased. It is concluded that the determination of erythrocyte glutathione is of differential diagnostic value in the characterization of osteomyelofibrosis.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
82.
Carsten Fülber Dan E. Demco Ofer Weintraub Bernhard Blümich 《Macromolecular chemistry and physics.》1996,197(2):581-593
The transverse nuclear 1H magnetization decay in poly(styrene-co-butadiene) (SBR) is investigated by editing 13C NMR spectra. This technique allows for the assignment of localized 1H dynamical information by discriminating the chemical sites based on their chemical shift in the 13C dimension. Here, the homo- and heteronuclear dipolar couplings contribute to the 1H NMR relaxation giving additional information to a homonuclear experiment. In this heteronuclear 2D experiment two prominent peaks are observed in the 13C dimension, which correspond to CH and CH2 groups, respectively. The decay rate in the 1H dimension is found for both groups to scale with the crosslink density. An additional ultra-fast magnetization decay is reported. The effect of the carbon black filler is investigated for this component. The analysis of the 13C NMR edited transverse 1H magnetization relaxation is a useful tool in combining high resolution NMR spectra with information on molecular dynamics, providing insight into crosslink density and filler effects. 相似文献
83.
CATs and HATs: the SLC7 family of amino acid transporters 总被引:18,自引:0,他引:18
Verrey F Closs EI Wagner CA Palacin M Endou H Kanai Y 《Pflügers Archiv : European journal of physiology》2004,447(5):532-542
The SLC7 family is divided into two subgroups, the cationic amino acid transporters (the CAT family, SLC7A1–4) and the glycoprotein-associated amino acid transporters (the gpaAT family, SLC7A5–11), also called light chains or catalytic chains of the hetero(di)meric amino acid transporters (HAT). The associated glycoproteins (heavy chains) 4F2hc (CD98) or rBAT (D2, NBAT) form the SLC3 family. Members of the CAT family transport essentially cationic amino acids by facilitated diffusion with differential trans-stimulation by intracellular substrates. In some cells, they may regulate the rate of NO synthesis by controlling the uptake of l-arginine as the substrate for nitric oxide synthase (NOS). The heterodimeric amino acid transporters are, in contrast, quite diverse in terms of substrate selectivity and function (mostly) as obligatory exchangers. Their selectivity ranges from large neutral amino acids (system L) to small neutral amino acids (ala, ser, cys-preferring, system asc), negatively charged amino acid (system xc–) and cationic amino acids plus neutral amino acids (system y+L and b0,+-like). Cotransport of Na+ is observed only for the y+L transporters when they carry neutral amino acids. Mutations in b0,+-like and y+L transporters lead to the hereditary diseases cystinuria and lysinuric protein intolerance (LPI), respectively. 相似文献
84.
Prognostic value of MMP-2, -9 and TIMP-1,-2 immunoreactive protein at the invasive front in advanced head and neck squamous cell carcinomas 总被引:10,自引:0,他引:10
Ondruschka C Buhtz P Motsch C Freigang B Schneider-Stock R Roessner A Boltze C 《Pathology, research and practice》2002,198(8):509-515
In head and neck cancer as well as in other carcinomas, tumor expansion and spread to distant sites require the secretion of destructive enzymes that degrade the extracellular matrix. A variety of proteases contribute to matrix destruction. Characteristics of the invasive tumor front may reflect tumor prognosis better than do other parts of the tumor. Therefore, it was the aim of the present study to (i) compare central and peripheral tumor zones for differences in the expression of matrix-metalloproteinases (MMP) -2 and -9 and their naturally occurring inhibitors (tissue inhibitor of matrix-metalloproteinases (TIMP) -1 and -2), (ii) examine the morphological potential of malignancy, and (iii) correlate these findings with clinicopathological parameters. The study population consisted of 106 surgical specimens of advanced head and neck squamous cell carcinomas. The invasive front was graded for malignancy, and immunohistochemical staining with MMP-2, MMP-9, TIMP-1 and TIMP-2 antibodies was performed. Both MMP-2 and MMP-9 were found to be significantly overexpressed at the tumor front. The MMP-2-positive invasive front exhibited diminished overall survival times. In multivariate analysis, MMP-2 expression retained its correlation with overall survival in addition to nodal status and total malignancy score. Expression of TIMP-2 correlated with local tumor invasion. We conclude that the expression of MMP-2 at the invasive front is a marker of poor survival and appears to be associated with early recurrence in initially lymph node-negative patients. 相似文献
85.
Meyer-Hoffert U Lezcano-Meza D Bartels J Montes-Vizuet AR Schröder JM Teran LM 《International archives of allergy and immunology》2003,131(4):264-271
BACKGROUND: Both CXC and CC chemokines play an important role in leukocyte recruitment. However, a systematic examination of their production by human airway epithelial cells (HAECs) has not been carried out. The objective of this study was to investigate whether Th1- and Th2-type cytokines regulate chemokine production in HAECs. METHODS: HAECs were grown from both nasal and bronchial tissue and subsequently stimulated with either Th1- or Th2-type cytokines. RESULTS: Constitutive mRNA expression for gro-alpha, IL-8 and RANTES was seen in both human nasal and human bronchial epithelial cells. IL-4 was the strongest stimulus for both gene expression and protein production of the chemokines RANTES, IL-8 and gro-alpha, while both IL-13 and IFN-gamma were weaker inducers of these chemokines, with the exception of gro-alpha (IL-13 was a strong stimulus for gro-alpha production). TNF-alpha synergized with IL-4, and to a lesser extent with IFN-gamma and IL-13, to release RANTES, IL-8 and gro-alpha. IL-4 and to a lesser extent IL-13 and IFN-gamma stimulated the production of MCP-3 and -4, eotaxin and eotaxin-2 immunoreactivities. However, no induction of the mRNAs encoding these chemokines was observed, suggesting that they may be released from a preformed pool within the HAECs. CONCLUSION: These findings suggest that when released into the airways, Th2- and to a lesser extent Th1-type cytokines may stimulate recruitment of eosinophils and neutrophils through the release of CC (RANTES, MCP-3 and -4, eotaxin and eotaxin-2) and CXC chemokines (gro-alpha and IL-8). 相似文献
86.
Schäfer P Tenschert W Cremaschi L Schröter M Zöllner B Laufs R 《Journal of medical virology》2001,65(1):85-89
A novel approach to predicting symptomatic cytomegalovirus (CMV) infections combines the level and the duration of viraemia in a single parameter. Sixty-four kidney transplant recipients were monitored by quantitative shell vial culture, pp65 antigenaemia, and polymerase chain reaction (PCR) of leucocytes. The area under the curve (AUC) of each parameter was determined from the onset of viraemia to the beginning of antiviral treatment. The AUC values were significantly higher in symptomatic than in asymptomatic patients. For antigenaemia and PCR, optimal AUC thresholds for predicting symptomatic CMV infections were determined. They were superior to standard cutoff levels of absolute viral load in sensitivity, specificity, and positive and negative predictive value. In 8 of the 23 patients who became symptomatic, impending clinical features were indicated earlier by the AUC thresholds than by standard viral load. In conclusion, the concept of the AUC should facilitate identification of patients at risk of symptomatic CMV infection. 相似文献
87.
Heinz C. Schröder August Bernd Rudolf K. Zahn Werner E.G. Müller 《Mechanisms of ageing and development》1983,22(1):35-50
Microtubules have been isolated from immature (3-4 weeks' old) and old (11-13 years' old) bovine brains. Quantitative studies revealed that the concentration of extractable microtubule protein per gram of wet brain decreased from 0.47 mg (immature animals) to 0.34 mg (old animals). The major components of microtubule protein (tubulin and high-molecular-weight microtubule-associated proteins) do not undergo an age-correlated change. Determination of the endogenous protein kinase activity revealed that the activity associated with "immature" calf brain microtubules was six times higher than the activity present in "old" preparations. In contrast, the stimulatory effect of cyclic AMP on protein phosphorylation in microtubules from old bovine brains exceeds nine-fold the value obtained from immature animals. After addition of casein (exogenous acceptor), the basal activities increased in both preparations without altering the age-correlated difference in the specific activity. By comparing the radioactivity pattern of sodium dodecyl sulfate polyacrylamide gels after autophosphorylation of microtubule protein with [gamma-32P]ATP, 1.5 moles of phosphate per mole of high-molecular-weight microtubule-associated protein were estimated to be incorporated in preparations from immature animals and 0.9 mole of phosphate per mole of associated protein in the experiments with "old" microtubule protein. Adenosine triphosphatase activity, associated with the high-molecular-weight microtubule-associated protein 1, was determined to be 15% reduced in preparations from old animals, compared to the activity in "young" preparations. In contrast, the guanosine triphosphatase activity increased five-fold during ageing; the higher activity of this enzyme was observed both during the initial and the steady-state phases of microtubule formation. 相似文献
88.
89.
90.
S?ren L Petersen Hans O Madsen Lars P Ryder A Svejgaard Tania N Masmas Ebbe Dickmeiss Carsten Heilmann Lars L Vindel?v 《Biology of blood and marrow transplantation》2004,10(5):337-346
Chimerism analysis of hematopoietic cells has emerged as an essential tool in nonmyeloablative hematopoietic stem cell transplantation. We have investigated the development of donor chimerism in granulocytes and CD4(+) and CD8(+) T cells in blood and bone marrow of 24 patients with hematologic malignancies who received HLA-identical sibling peripheral blood stem cell grafts after conditioning with fludarabine and 2 Gy of total body irradiation. The T-cell chimerism of blood and bone marrow was tightly correlated. Complete donor chimerism was reached earlier in the granulocytes than in the T cells. Mixed T-cell chimerism was common at the time of onset of acute graft-versus-host disease (aGVHD), and both CD4(+) and CD8(+) donor T-cell chimerism increased with the occurrence of aGVHD grades II to IV (P =.0002 and P =.019, respectively). The rate of disappearance of recipient CD8(+) T cells was faster in patients with aGVHD grades II to IV than in patients without clinically significant aGVHD (P =.016). This observation indicates a role of graft-versus-lymphohematopoietic tissue reactions in creating complete donor T-cell chimerism. A donor CD8(+) T-cell count above the median on day +14 increased the risk of subsequent development of aGVHD grades II to IV (P =.003). 相似文献