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91.
Stefan Dinges 《Strahlentherapie und Onkologie》1998,174(7):386-387
Ohne Zusammenfassung 相似文献
92.
Stefan Somlo 《Clinical and experimental nephrology》1998,2(3):211-217
Conclusion The past decade has seen extraordinary progress in the study of autosomal-dominant polycystic kidney disease. The 2 major
genes for this disorder have been identified. Animal models of ADPKD have been produced. The molecular basis of the disease
has been characterized. ADPKD is a “second-hit” disease, much like many cancer predisposition syndromes. This has profound
implications for our understanding. The progression of ADPKD in individual patients is likely related more to their individual
rate of acquisition of second hits at thePKD1 orPKD2 locus than to the inherited germ line mutation itself. Therapeutic approaches will perhaps now be considered, which will
include interventions that may limit the rate at which somatic mutations occur in the kidney. The major focus of research
at present is to elucidate the normal functions ofPKD1 andPKD2. Protein binding partners are being sought for both proteins. The possible calcium channel function ofPKD2 is being investigated. The downstream effects of cellular deficiency of either protein are likely to yield many clues. Modifying
genetic factors that may independently affect disease progression are likely to be identified using the several mouse models.
Perhaps the next decade will bring great strides in understanding and in potential therapy for this common disease.
This paper was presented at the 2nd International Forum “The Frontiers of Nephrology,” Tokyo, May 10, 1998. 相似文献
93.
Thomas Lachmann Stefan Berti Teija Kujala Erich Schr?ger 《International journal of psychophysiology》2005,56(2):105-120
The present study addressed auditory processing in 8-11-year-old children with developmental dyslexia by means of event-related brain potentials (ERP). Cortical sound reception was evaluated by recording N250 responses to syllables and tones and cortical sound discrimination by analyzing the mismatch negativity (MMN) to syllable and tone changes. We found that both cortical sound reception and sound discrimination were impaired in dyslexic children. The analysis of the data obtained from two dyslexic subgroups, Dyslexics-1 being impaired in non-word reading (or both non-word and frequent word reading) and Dyslexics-2 in frequent word reading but not in non-word reading, revealed that the MMN was specifically diminished in the latter group whereas it was normal-like in Dyslexics-1. However, no differences were found between these subgroups in sound reception as indicated by the responses elicited by the standard stimuli. These results show that different diagnostic subgroups of dyslexics have different patterns of auditory processing deficits as suggested by similarly impaired sound reception in both dyslexic groups and the sound-discrimination impairment specific to one of the groups. 相似文献
94.
WIF1, a component of the Wnt pathway, is down-regulated in prostate, breast, lung, and bladder cancer 总被引:19,自引:0,他引:19
95.
96.
Dengjel J Decker P Schoor O Altenberend F Weinschenk T Rammensee HG Stevanovic S 《European journal of immunology》2004,34(12):3644-3651
T-helper (Th) cells play an important role in orchestrating the effector function of CTL in anti-tumor immunity. However, only a limited number of Th cell epitopes has been characterized. Here we describe a novel approach for identifying naturally processed and presented peptides derived from chosen antigens. This method combines a transfection step of antigen-presenting cells with a vector encoding a fusion protein between the Ii chain and the antigen of interest, elution of the HLA-bound peptides and identification of the antigen-derived peptides by mass spectrometric comparison to the non-transfected cells. In vitro-stimulated Th cells against the identified peptide of interest specifically recognize transfectants overexpressing the cognate antigen. Using this approach, we were able to identify the HLA-DR4-restricted Th cell epitope NPPSMVAAGSVVAAV derived from cyclin D1, which is frequently overexpressed in tumors. This method will help in identifying peptide candidates for vaccination studies for tumor immunotherapy. 相似文献
97.
Murine macrophages were treated with various doses of cyclosporin A (CsA) to enhance the killing of Leishmania major parasites. CsA reduced the rate of infected cells from 75% in non-treated controls to less than 15% with 1 micro g CsA/ml in a dose-dependent manner. The leishmanicidal effect was also observed when CsA was added 48 h after the infection of macrophages. In contrast, FK506, another structural non-related immunosuppressive drug with antiparasitic activities, showed no effect on the ability of macrophages to kill intracellular Leishmania parasites. Since nitric oxide has been identified as a key molecule for the leishmanicidal function of macrophages, we analyzed the role of this molecule. There was no influence on the leishmanicidal effect of CsA when L- N-(1-iminoethyl)lysine, a potent and selective inhibitor of mouse inducible nitric oxide synthase, was added. Furthermore, the presence of the macrophage-inhibiting cytokines interleukin (IL)-10 and IL-13 simultaneously or prior to CsA did not inhibit leishmania killing, while both cytokines completely prevented parasite killing by macrophages activated with gamma interferon and tumor necrosis factor (TNF). CsA was fully active on macrophages from TNF-receptor p55 knockout mice arguing against autocrine activation by TNF. We therefore conclude that the antileishmanial effect of CsA is independent of effector mechanisms employed by macrophage-activating cytokines. 相似文献
98.
Dudel J Hallermann S Heckmann M 《Pflügers Archiv : European journal of physiology》2000,441(2-3):175-180
Quartz glass electrodes are superior to conventional glass electrodes for low-noise recording. They have better electrical characteristics and hydrophobic surfaces which resist creeping of salt solutions. We used oxy-hydrogen heating with program-controlled gas pressure to melt quartz glass capillaries. Usually, the relative wall thickness (the quotient of the outer and inner diameters do/di) of capillaries is, at best, maintained up to the electrode tip. If tips with thicker walls can be produced, coating and other surface treatments can be avoided. We found that programmed heating periods without pull allowed an fivefold increase of do/di in the tip region. Since do/di is inversely proportional to input capacity, the recording noise was minimized and became insignificant relative to amplifier and holder noise. A sample patch-clamp recording is shown. 相似文献
99.
V. V. Raevskii Ch. Tegetmayer A. A. Trifonov 《Neuroscience and behavioral physiology》1993,23(6):529-533
The influence of the destruction of the catecholaminergic (CA) system on the reactions of neurons of the somatosensory zone of the cortex elicited by stimulation of the sciatic nerve, and on the features of the modulation of these reactions following the stimulation of the region of the basal nuclei (source of cholinergic innervation of the neocortex) and the microiontophoretic application of acetylcholine (ACh), was investigated in mongrel infant rats, 21–31 days of age. It was demonstrated that destruction of the CA system in newborn rats increases the reactivity of neurons somatosensory cortex to sensory stimulation, has no influence on the modulating effect of the cholinergic system, of the forebrain, and leads to intensification of the modulating influence of applied ACh [2].Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 42, No. 5, pp. 1018–1022, September–October, 1992. 相似文献
100.