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41.
O van der Heijden HC Chiu TC Park H Takahashi VA LiVolsi JI Risinger JC Barrett A Berchuck AC Evans K Behbakht AW Menzin PC Liu I Benjamin MA Morgan SA King SC Rubin J Boyd 《Canadian Metallurgical Quarterly》1998,23(4):243-247
The degree and nature of patient involvement in consultations with health professionals influences problem and needs recognition and management, and public accountability. This paper suggests a framework for understanding the scope for patient involvement in such consultations. Patients are defined as co-producers of formal health services, whose potential for involvement in consultations depends on their personal rights, responsibilities and preferences. Patients' rights in consultations are poorly defined and, in the National Health Service (NHS), not legally enforceable. The responsibilities of patients are also undefined. I suggest that these are not to deny, of their own volition, the rights of others, which in consultations necessitate mutuality of involvement through information-exchange and shared decision-making. Preferences should be met insofar as they do not militate against responsibilities and rights. 相似文献
42.
JG Izzo VA Papadimitrakopoulou XQ Li H Ibarguen JS Lee JY Ro A El-Naggar WK Hong WN Hittelman 《Canadian Metallurgical Quarterly》1998,17(18):2313-2322
Cyclin D1 proto-oncogene is a key regulator of the mammalian cell-cycle acting at the restriction point in late G1. Amplification of the cyclin D1 locus, located on chromosome 11q13, as well as cyclin D1 protein overexpression have been reported in several human malignancies. The purpose of this study was to evaluate cyclin D1 gene copy status and protein expression during the multistep process of head and neck tumorigenesis, using a combination of fluorescence in situ hybridization and immunohistochemistry techniques. From 29 selected patients presenting with head and neck squamous carcinoma and whose tumor cytospins had been previously screened for presence (16 cases) or absence (13 cases) of amplification at the 11q13 band, we analysed 46 paraffin-embedded tissue specimens that demonstrated, besides the primary tumor, the presence of contiguous adjacent normal tissue and/or premalignant lesions. Of the 16 amplified cases, nine demonstrated a continuous progression from premalignant to invasive carcinoma and seven (77.7%) of these cases showed cyclin D1 gene amplification in premalignant lesions prior to development of invasive carcinoma. Increased cyclin D1 protein expression was observed in all 16 amplified tumors and five of the 13 (38.4%) non-amplified tumors. Interestingly, dysregulated cyclin D1 expression was also found in the premalignant lesions adjacent to all 16 amplified tumors, and it appeared to precede cyclin D1 gene amplification. In contrast no dysregulated expression was detected in the premalignant lesions of the non-amplified tumors. In conclusion, these findings provide strong evidence for early dysregulation of cyclin D1 expression during the tumorigenesis process and suggest that dysregulated increased expression precedes and possibly enables gene amplification. 相似文献
43.
44.
CT Lai VA Tanay GA Rauw AN Bateson IL Martin GB Baker 《Canadian Metallurgical Quarterly》1997,704(1-2):175-179
Reported here is a rapid, sensitive and relatively inexpensive procedure using gas chromatography with nitrogen-phosphorus detection (GC-NPD) to quantify buspirone levels in brains of rats. The analyte was directly extracted from brain homogenate with toluene after basification and then subjected to GC-NPD analysis using a capillary column. The calibration curves were linear over the range of 10 to 320 ng per 2 ml of brain homogenate, with typical r2 values >0.99. The assay was highly reproducible and gave peaks with excellent chromatographic properties. 相似文献
45.
VA Poberskaia LV Kozhelupenko EA Kradinova OI Dement''eva 《Canadian Metallurgical Quarterly》1995,75(4):10-13
A favourable effect of sanatorium treatment on the key body functions was found in children with thyroid hyperplasia consequent to environmental pollution due to Chernobyl accident. It is emphasized that balneofactors in the above children should be used in sparing regimens. 相似文献
46.
JG Gribben GJ Freeman VA Boussiotis P Rennert CL Jellis E Greenfield M Barber VA Restivo X Ke GS Gray 《Canadian Metallurgical Quarterly》1995,92(3):811-815
The regulation of T cell-mediated immune responses requires a balance between amplification and generation of effector function and subsequent selective termination by clonal deletion. Although apoptosis of previously activated T cells can be induced by signaling of the tumor necrosis factor receptor family, these molecules do not appear to regulate T-cell clonal deletion in an antigen-specific fashion. We demonstrate that cross-linking of the inducible T-cell surface molecule CTLA4 can mediate apoptosis of previously activated human T lymphocytes. This function appears to be antigen-restricted, since a concomitant signal T-cell receptor signal is required. Regulation of this pathway may provide a novel therapeutic strategy to delete antigen-specific activated T cells. 相似文献
47.
NV Beloborodova VA Kurchavov VV Pozdorovkina NB Bo?ko EA Rogatina AM Demina 《Canadian Metallurgical Quarterly》1998,43(4):24-29
Methods for preventing and treating Ebola virus hemorrhagic fever are not still available despite the fact that this virus have been studied for 20 years. Methods of immunization of the animals (sheep, goats) non-susceptible to Ebola virus with live virus preparations were developed to obtain the hyperimmune anti-Ebola virus sera required to have highly immune antivirus gamma-globulins. These methods made it possible to obtain the immune sera having high virus-neutralizing antibodies. Caprine immunoglobulins were obtained from sera by fractionation of immune sera by Kohn's method. The neutralization indices of the immunoglobulins obtained were at least Ig. When administered in the first hours of infection, the protective effect of these preparations was shown on guinea pigs infected with LD50 of the strain pathogenic to the animals. Preclinical trials of these immunoglobulins on laboratory animals and clinical trials on volunteers were performed. The preparation was used as a preventive agent when accidents took place at the laboratory working with Ebola virus. The similar preparation from equine sera having high neutralizing and protective properties was elaborated at the Virological Center, Microbiological Institute, Russian Ministry of Defense. Its prophylactic efficiency was also shown in infected gamadrias. 相似文献
48.
Expansion of DNA trinucleotide repeats (TNRs) is the causative mutation in a growing number of human genetic diseases. Large expansions of a CTG tract were obtained and shown by genetic and physical assays to be length-dependent sites of chromosome breakage in Saccharomyces cerevisiae. Deletion of RAD27, which encodes a nuclease involved in Okazaki fragment processing, caused length-dependent destabilization of CTG tracts and a substantial increase in expansion frequency. The genetic assay described here can be used to evaluate other factors that induce TNR expansion or chromosome fragility in humans. 相似文献
49.
Tukhtaev R. K. Aleksandrov V. V. Boldyrev V. V. 《Combustion, Explosion, and Shock Waves》1977,13(2):234-236
Combustion, Explosion, and Shock Waves - 相似文献
50.
KS Makarova IuI Vul'f IA Seledtsov VA Ratner 《Canadian Metallurgical Quarterly》1995,31(12):1614-1629
Transposons of gypsy group are assigned to LTR-containing retrotransposons present in the genomes of invertebrates, fungi, and plants. In this work, a theoretical analysis of the potential products of ORFs of these retrotranposons was conducted. Alignments were obtained and trees of similarity were constructed for domains of the POL region. On the basis of the obtained data, two hypothetically monophyletic subgroups of transposons were distinguished within the framework of the gypsy group, settling the genomes of taxonomically related organisms (the subgroup of "true" gypsy of insects and the subgroup of gypsy-like transposons of plants and fungi). A number of peculiarities of the topology of these trees hypothetically indicate cases of genetic conversion and recombination of domains accompanying the evolution of this group. The amino acid substitution fixation rate was evaluated on the basis of comparison of sequences of the protein products of ORFs. Estimates of the time of divergence of subgroups of gypsy-group transposons are significantly less than estimates of the times of divergence of their host species. One explanation for this discrepancy might be the hypothesis of settlement by transposons of the genomes of isolated host species. 相似文献