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91.
Making routine clinical-care-data available for medical research requires adequate consent to legitimize use and exchange. While, public interest in supporting medical research is increasing, individuals often find it difficult to actively enable researchers to access their data. In addition to broad consent, the idea of (consent-free) data donation has been brought into play as another way to legitimize secondary research use of medial data. However, flanking the implementation of broad consent policies or data donation, the attitude of patients, and the general public toward different aspects of these approaches needs to be assessed. We conducted two empirical studies to this end among Dutch patients (n = 7430) and representative German citizens (n = 1006). Wide acceptance of broad consent was observed among Dutch patients (92.3%), corroborating previous findings among German patients (93.0%). Moreover, 28.8% of the Dutch patients generally approved secondary data-use for non-academic research, 42.3% would make their decision dependent upon the type of institution in question. In the German survey addressing the general population, 78.8% approved data donation without explicit consent as an alternative model of legitimization, the majority of those who approved (96.7%) would allow donated data to be used by universities and public research institutions. This willingness to support contrasted sharply with the fact that only 16.6% would allow access to the data by industry. Our findings thus not only add empirical evidence to the debate about broad consent and data donation, but also suggest that widespread public discussion and education about the role of industry in medical research is necessary in that context.Subject terms: Medical research, Social sciences  相似文献   
92.
Summary To study morphogenetic events of rotavirus SA11-infected MA104 cells with strictly defined reagents we produced monoclonal antibodies against synthetic peptides from both outer capsid proteins VP4 (aa residues 228–241: QNTRNIVPVSIVSR) and VP7 (aa residues 319–326: SAAFYYRV) of simian rotavirus SA11. Two of the selected monoclonal antibodies proved to be reactive with determinants of SA11-infected MA104 rhesus monkey kidney cells, with purified SA11 as well as with the particular peptides used for immunization. The anti-VP4 antibody had a demonstrable neutralizing titer of 200 (50% focus reduction) whereas the anti-VP7 MuMAb revealed no detectable neutralizing activity. In peptide-inhibition experiments, the corresponding peptide inhibited its MuMAb whereas the noncorresponding peptide had no effect on antibody binding to intracellular viral antigen. Localization of VP7 was preceded by VP4 as shown by immunofluorescence microscopy.  相似文献   
93.
Two types of photoreceptors, rods and cones, coexist in the vertebrate retina. An in-depth analysis of the retinal circuitry that transmits rod and cone signals has been hampered by the presence of intimate physical and functional connections between rod and cone pathways. By deleting the cyclic nucleotide-gated channel CNG3 we have generated a mouse lacking any cone-mediated photoresponse. In contrast, the rod pathway is completely intact in CNG3-deficient mice. The functional loss of cone function correlates with a progressive degeneration of cone photoreceptors but not of other retinal cell types. CNG3-deficient mice provide an animal model to dissect unequivocally the contribution of rod and cone pathways for normal retinal function.  相似文献   
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95.
Leg ulcers are common. They cause a substantial burden to the patient and society. However, there is no need for therapeutic nihilism. The target of leg ulcer therapy is the individual patient. To be treated in a rational and successful way, exact diagnosis of the underlying cause(s) and associated diseases is necessary. This can be done in the most effective way with an interdisciplinary approach. The collection of cases demonstrates the need for careful clinical investigation substantiated and supported by vascular, histopathologic, and microbiologic techniques whenever needed. It is difficult to heal every ulcer completely, but improvement of the medical situation as well as the quality of life of the patient is possible in most cases.  相似文献   
96.
Most bioartificial liver support systems are based on hollow fiber capillaries within modified dialysis cartridges or more sophisticated bioreactor constructions. Due to their design microscopic follow-up of reorganization and growth of tissue between the hollow fibers is not possible. The SlideReactor is a simple hollow fiber based bioreactor construction suitable for light microscopy and time-lapse video observation. The SlideReactor offers a cell compartment separated from a medium inflow and outflow compartment. Cell compartment access ports enable easy filling of the cell compartment with cell suspension, as well as fixation of the tissue. For more complex procedures or full access to all the cells, the bioreactor can be opened easily by cutting the silicone seal with a scalpel. Due to its simple design and the utilization of standard materials, it could serve as a suitable, cost-efficient tool to evaluate the behavior of cells cultured between hollow fiber capillaries. The paper describes the production process: similar to open source projects in software engineering, we would like to propose the concept as an open platform to anyone interested in hollow fiber based cell culture.  相似文献   
97.
Appropriate software tools may improve communication and ease access to knowledge for research groups. A weblog is a website which contains periodic, chronologically ordered posts on a common webpage, whereas a wiki is hypertext-based collaborative software that enables documents to be authored collectively using a web browser. Although not primarily intended for use as an intranet-based collaborative knowledge warehouse, both blogs and wikis have the potential to offer all the features of complex and expensive IT solutions. These tools enable the team members to share knowledge simply and quickly-the collective knowledge base of the group can be efficiently managed and navigated.  相似文献   
98.
BACKGROUND: Interleukin-2 (IL-2) is a potent cytokine with potential activity against several tumors including Ewing tumors (ET). Side effects of systemic IL-2 can be circumvented by the use of transgenic tumor cells. However, in vitro manipulation may change the overall gene expression profile of tumor cells unfavorably. Therefore, we assessed gene expression profiles, safety, and immunomodulatory efficacy of IL-2 transgenic (IL-2-tg) ET cells in vitro and in NOD/scid mice. PROCEDURE: Viable wild type A673 tumor cells were co-cultured together with irradiated IL-2-tg or mock-transfected cells and HLA matched peripheral blood mononuclear cells. Activation of T and NK cells was assessed by FACS analysis. The effect of irradiated IL-2-tg cells on tumor growth in vivo was investigated by using NOD/scid mice. Gene expression profiles of wild type and transfected cells were analyzed with Affymetrix HG-U95A microarrays. RESULTS: IL-2-tg cells activated and increased the number of T cells and NK cells in vitro. Co-culture with IL-2-tg but not with mock-transfected cells almost completely suppressed wild type tumor cell growth in vitro. Cell depletion experiments indicated a major contribution of NK cells to this tumor cell suppression. Co-transfer of irradiated IL-2-tg cells significantly reduced wild type tumor growth in NOD/scid mice. Side effects in the treated animals were not observed and no tumor growth was observed after injection of irradiated IL-2-tg cells alone. Gene expression profiling revealed a substantial degree of homogeneity of gene expression in transfected and wild type cells and suggests that transfection and selection procedures had no major impact on the gene expression profile. CONCLUSIONS: Next to a high degree of homogeneity between transgenic and wild type cells, our data suggest that irradiated IL-2-tg ET cells can activate cytolytic effector cells. These cells may have therapeutic potential for ET patients.  相似文献   
99.
100.
Primary human liver cells from donor organs unsuitable for transplantation were cultivated in bioreactors developed for extracorporeal liver support. Because each system contains cells originating from an individual organ, each bioreactor culture must be individually characterized. The objective of this study was to identify suitable decisive parameters for the evaluation of cell culture performance. We analyzed the data from 47 bioreactor cultures containing 437 +/- 110 g of cells. Choosing urea production as the decisive parameter, the bioreactor cultures were divided into high-performance (daily urea production > or = 110 mg per bioreactor between culture days 3 and 14) and low-performance cultures. Comparing the mean courses of the groups revealed a significant distinction in most other investigated biochemical parameters. In conclusion, urea production seems to be an appropriate parameter for evaluating the performance of liver cell cultures in bioreactors because it corresponds to all other evaluated parameters of cell function.  相似文献   
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