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排序方式: 共有479条查询结果,搜索用时 390 毫秒
471.
W Hao DV Serreze DK McCulloch JL Neifing JP Palmer 《Canadian Metallurgical Quarterly》1993,6(6):787-798
In NOD mice, endogenous retroviruses including intracisternal type A particles (IAP) are expressed in the pancreatic beta cells. Furthermore, in these mice, insulin autoantibodies (IAA) cross-react with retroviral protein p73 (the IAP gag gene product), suggesting molecular mimicry between insulin and p73. We therefore investigated whether IAA and insulin antibodies (IA) associated with human IDDM cross-reacted with p73. Fifty IAA positive sera from 30 newly diagnosed IDDM before insulin therapy and 20 non-diabetic first degree relatives of IDDM and 27 IA positive sera from insulin treated IDDM, initially defined as IAA or IA positive by radioimmunoassay, were evaluated. Binding to insulin and to p73 of these sera were analysed by ELISA. Approximately 65% of sera which bound insulin by ELISA also bound p73. Only one sample negative for insulin binding was positive for p73 binding. Preabsorption with either insulin or p73 inhibited binding to both insulin and p73. However, preabsorption with mouse hemoglobin had no effect on their binding. Repeat measurement of binding to insulin and p73 in 10 non-diabetic first degree relatives of IDDM over an average of 16.6 months showed that each individual's reactivity to insulin and to p73 was relatively stable over time. Furthermore, in different individuals, binding to p73 and to insulin was closely correlated over time. In addition, 75 healthy teenagers (IAA negative by RIA) were used as normal controls in this study. p73 binding was found in only two (2.7%) of the 75 subjects. These results indicate that approximately 65% of ELISA (+) IAA and IA subjects have antibodies which recognize both insulin and p73, suggesting that IAA and IA from some subjects recognize an epitope shared between human insulin and the murine gag gene product. This raises the possibility that for some subjects who are IAA positive, the immunizing antigen may be antigenically similar to p73, rather than insulin, and that endogenous retroviruses may be involved in human IDDM. 相似文献
472.
Random samples of nurses in two states which differed in abortion statues were sent questionnaires. Content areas included experience with 12 specific nursing activities associated with abortion, willingness to participate in the same activities, and extent of agreement with statements related to abortion. Attitudes toward abortion were inferred from the willingness-to-participate items and from the agreement section. These two measures correlated highly suggesting a common underlying dimension. However, the two samples differed significantly in extent of agreement but did not differ in willingness to participate. These results were interpreted as supporting the position that attitudes derived from items using situational contexts might bear a better relationship to behavior. The findings also suggest that abortion facilities can probably be staffed without violating personal preferences since so many expressed willingness to participate in at least some of the activities. Comparison across the two samples suggest that increased experience or even the potential for experience with abortion patients tended to increase the favorableness of attitudes toward this issue. 相似文献
473.
DV Pastrana N Raghavan P FitzGerald SW Eisinger C Metz R Bucala RP Schleimer C Bickel AL Scott 《Canadian Metallurgical Quarterly》1998,66(12):5955-5963
Filarial nematode parasites establish long-term chronic infections in the context of an antiparasite immunity that is strongly biased toward a Th2 response. The mechanisms that lead to this Th2 bias toward filarial antigens are not clear, but one possibility is that the parasites produce molecules that have the capacity to proactively modify their immunological environment. Here we report that filarial parasites of humans secrete a homologue of the human proinflammatory cytokine macrophage migration inhibitory factor (MIF) that has the capability of modifying the activity of human monocytes/macrophages. A cDNA clone isolated from a Brugia malayi infective-stage larva expression library encoded a 12.5-kDa protein product (Bm-MIF) with 42% identity to human and murine MIF. MIF homologues were also found to be expressed in the related filarial species Wuchereria bancrofti and Onchocerca volvulus. Bm-mif was transcribed by adult and larval parasites, and the protein product was found in somatic extracts and in the parasite's excretory-secretory products. Immunohistocytochemistry revealed that Bm-MIF was localized to cells of the hypodermis/lateral chord, the uterine wall, and larvae developing in utero. Unexpectedly, the activities of recombinant Bm-MIF and human MIF on human monocytes/macrophages were found to be similar. When placed with monocytes/macrophages in a cell migration assay, Bm-MIF inhibited random migration. When placed away from cells, Bm-MIF induced an increase in monocyte/macrophage migration that was specifically inhibited by neutralizing anti-Bm-MIF antibodies. Bm-MIF is the first demonstration that helminth parasites produce cytokine homologues that have the potential to modify host immune responses to promote parasite survival. 相似文献
474.
LM Clark WM McDonald KA Welsh-Bohmer IC Siegler DV Dawson LA Tupler KR Krishnan 《Canadian Metallurgical Quarterly》1998,44(7):592-599
Even today psychotic depression is connected to a lot of unanswered questions. A self-questionnaire (BFD) was developed in order to evaluate cognitions corresponding to mood congruent depressive delusions. They were assumed to indicate psychotic depression and to be related to severity of the depressive syndrome. 42 depressed inpatients were examined by the BFD, the Hamilton Depression Scale (HAMD) and the Beck Depression Inventory (BDI). BFD scores were found increased in psychotic depression (p = 0.009) and correlated to BDI scores (p = 0.002). 19 re-examined patients showed a significant improvement in HAMD and BDI scores but not concerning the delusion indicating cognitions (BFD), which were significantly correlated to suicidality items of BDI and HAMD (p = 0.005). The results prove the delusion indicating nature of cognitions measured by the BFD and their correlation to severe depression. Differences in treatment response are indicated and persisting or increasing BFD scores seem to be accompanied by more severe suicidal tendency. 相似文献
475.
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477.
The application of nanostructured luminescent silicon nitride (SiN(X)) thin films for label-free cell imaging is reported for the first time. Different strong local fields ensured by various molecules concentrated in various cell compartments can lead to the creation of preferential electronic conditions for radiative recombination of photogenerated charge carriers via a given electronic channel. Thus, highly contrasted multicolor luminescent cell imaging under one photon excitation becomes possible. The described label-free bio-imaging approach has good compatibility with fluorescence optical microscopy, and allows rapid and efficient cell imaging and cell line recognition. 相似文献
478.
OBJECTIVE: Community-based treatment of persons with serious mental illness requires providers to become involved in clients' personal lives to a greater degree than does hospital-based treatment. The study examined attendant ethical dilemmas, especially for staff who lack professional training or work in rural communities. METHODS: A total of 95 staff members from five community mental health centers read 14 vignettes describing ambiguous ethical dilemmas involving professional role boundaries or client confidentiality. Twenty-seven staff members were from rural agencies, and 68 from urban-suburban agencies; 60 were direct care staff, and 35 were supervisory. Participants were asked to make and justify a more conservative or a less conservative decision in response to each dilemma. RESULTS: Years of experience as a mental health provider and previous ethics training correlated positively with staff having experienced more situations similar to those in the vignettes; however, these variables were not related to the decision made or the type of ethical justification for it. When the analysis controlled for experience and previous ethics training, staff made fewer conservative decisions in boundary dilemmas than in confidentiality dilemmas. Compared with nonrural providers, rural providers had experienced more boundary dilemmas and made fewer conservative decisions in response to them. CONCLUSIONS: Boundary problems occur frequently in community-based services, especially in rural settings, and may or may not be handled conservatively. With the expansion of case management and other in vivo services, better understanding of ethical risks and informal practices will help improve services and provide appropriate training and supervision of staff. 相似文献
479.
Vitalii Serdiuk Oleh Shevchuk Kovalenko Tetiana Natalya Bukartyk Viktor Tokarev 《应用聚合物科学杂志》2023,140(1):e53254
A series of reactive copolymers with peroxide functionality (RCPFs) were synthesized via radical copolymerization of monomer mixtures in an organic solvent comprised of a peroxide monomer 5-(tert-butyl peroxy)-5-methylhex-1-en-3-yne, acrylamide, maleic anhydride, and butyl methacrylate. Peroxide functionality allows the RCPFs to initiate a variety of radical processes, including cross-linking of organic polymers. Hydrophilic monomer subunits (acrylamide and maleic anhydride) within the RCPF macromolecules promote cross-linking of water-soluble polymers. We aimed to investigate RCPF comonomer ratio and its effects on copolymerization kinetics and composition, as well as physico-chemical and colloidal properties. We also evaluated and characterized the kinetic parameters of the thermal decomposition of peroxide moieties in the synthesized RCPF. Findings revealed that RCPF possessed surface-active properties and reduced surface tension at its aqueous solution–air interface. The data indicated that the decomposition process complied with the first-order kinetics, and complex thermal analysis confirmed the presence of peroxide moieties. RCPFs' ability to cross-link water-soluble polymers was demonstrated on poly(acrylamide) and poly(vinyl alcohol). 相似文献