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81.
How health–disease is perceived or conceptualized is important for nursing research There is increasing evidence that individual representations are important in constructing the experience of health–disease What is the personal saliency of health–disease for the individual? To explore the patterns of meaning inherent in health–disease, a card sort was undertaken among 15 healthy individuals and 15 individuals with chronic renal disease Both groups were given 28 cards to sort twice once for when they felt ‘well’ and again for when they felt ‘ill’ The theoretical basis underlying the items of the card sort was a model of wellness-illness being developed Latent partition analysis was used to cluster the concepts from each data set followed by multi-dimensional scaling to analyse the structure of the intercategory probability estimates A possible unidimensional pattern of meaning (harmony) emerged for the ‘well’ data and a two-dimensional pattern (disharmony and optimism) for the ‘ill’ data This represents a preliminary step in the development of a theoretical model that would permit assessment of the meaning of health–disease for the individual  相似文献   
82.
The AA. refer on the first Italian case of amoebae "Limax" primitive myelitis in a 25-year-old man. Microscopical observation showed amoebae free-living, but their cultivation and identification were not possible. The patient recovered because of the propriety of diagnosis and therapy with amphotericin B.  相似文献   
83.
A simple and rapid method for the simultaneous determination of 11 metals (As, Be, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in urine by inductively coupled argon plasma-atomic emission spectrometry is presented. Acidification of the urine was the only sample preparation required. Background correction was applied to ensure accuracy. Analytical calibration was based on matrix matching using a "simulated urine" solution. Detection limits in the low mg/L range and linearity over three orders of magnitude were obtained for all 11 metals. In the Occupational Health Laboratory, this procedure has been applied for routine screening of workers for occupational exposure to toxic metals.  相似文献   
84.
Summary The in vitro and in vivo antineoplastic activity of 5-aza-2-deoxycytidine (5-AZA-dCyd) and 3-deazauridine (3-DU) against L1210 and L1210/ARA-C (resistant to cytosine arabinoside) leukemic cells were investigated. L1210/ARA-C cells were more sensitive to the inhibitory effects of 3-DU than L1210 cells. Deoxycytidine completely reversed the in vitro cytotoxic effects produced by 3-DU on L1210 cells, but not those produced in L1210/ARA-C cells. L1210/ARA-C cells, which are deficient in deoxycytidine kinase, were completely resistant to the antileukemic effects of 5-AZA-dCyd, whereas this analogue produced a very potent antileukemic effect against L1210 cells. To study the in vivo interaction of 5-AZA-dCyd and 3-DU with respect to drug resistance, mice were simultaneously injected i. v. with 104 L1210 cells plus 102 L1210/ARA-C cells. A 9-h i. v. infusion of 5-AZA-dCyd (12.8 mg/kg) or 3-DU (186 mg/kg) produced an increase in life span of 56% and 26%, respectively. However, the sequential administration of 5-AZA-dCyd followed by 3-DU produced a 265% increase in life span and 7/10 longterm survivor, a very potent antileukemic effect. These results suggest that 3-DU is an excellent agent for use in combination chemotherapy to overcome drug resistance to the deoxycytidine analogue, 5-AZA-dCyd.This investigation was supported by grant MA-6356 from the Medical Research Council of Canada and by LEUCAN  相似文献   
85.
BACKGROUND: It has been argued that lay interviewers' use of fully-structured interviews could lead to a diagnostic pattern different to that by treating physicians. Clinical interviewers in community samples should probably identify cases that are closer to those seen in clinical settings. The greatest advantage of using clinical interviewers consists of the immediate assessment of a possible psychopathology, i.e. the evaluation of current disorders. METHODS: Two thousand three hundred and sixty-three citizens from the community of Sesto Fiorentino, Italy, were interviewed by their own general practitioners using the Mini International Neuropsychiatric Interview (MINI). Positive cases for any lifetime psychiatric disorder as well as a random sample of the negative cases were re-interviewed by psychiatrists or trained residents in psychiatry using the Florence Psychiatric Interview (FPI). RESULTS: The point prevalence for any current disorder was 8.7%; the two disorders with the highest prevalence were generalised anxiety disorder (2.9%) and major depressive episode (2.7%). The figures increase about 50% when the sub-threshold sequelae of previous disorders are considered. Current comorbidity was generally high. The one-year prevalence of any disorder was 10.6%. Ninety-two percent of the cases sought help, 82% were being treated at the moment of interview. Social impairment was considerable. CONCLUSIONS: The period prevalence rates for most of the disorders considered were generally comparable with the range defined by previous studies conducted in other Western countries, despite using different methodologies. Conversely, the use of health facilities, the treatment received and the social impairment were much higher than those reported by the other studies, suggesting a greater similarity with the clinical samples.  相似文献   
86.
Summary Spontaneous mitotic intragenic and intergenic recombination at various sites is enhanced 10 to 100 fold in the methyl methanesulfonate (MMS)-sensitive mutants mms9-1, mms13-1, and mms21-1 of Saccharomyces cerevisiae. All three mutants show elevated rates of spontaneous mutation. Sporulation is reduced in diploids homozygous for any of the three mutations, and a deficiency in meiotic recombination and meiotic chromosome segregation is observed. Pleiotropic effects on cell viability, growth rate, and radiation sensitivity, in combination with the alterations in recombination and mutagenesis displayed by mutant strains, suggest that the MMS9, MMS13, and MMS21 genes play important roles in DNA replication and/or genetic recombination.  相似文献   
87.
88.
Thymic stromal cell specialization and the T-cell receptor repertoire   总被引:5,自引:0,他引:5  
Ten years ago, we proposed a model for thymus function in which thymic epithelial cells are primarily responsible for imprinting major histocompatibility complex (MHC)-restricted specificity, and bone marrow-derived macrophages or dendritic cells are responsible for the induction of self-tolerance. Since then, transgenic and knockout models have allowed for a dissection of thymic stromal components in vivo, leading to a new understanding of their specialized functions. We have determined that with regard to class II-restricted CD4 T-cell development, two distinct subsets of thymic epithelium help shape the repertoire: Cortical epithelium appears solely responsible for positive selection, whereas a fucose-bearing subset of medullary epithelium is specialized for negative selection. This absolute separation of positive and negative selection into two distinct spatial and temporal compartments leads to a much simpler view of the process of repertoire selection. Finally, a novel view of the function of the thymic medulla is discussed.  相似文献   
89.
Lo SK  Woo PC  Yuen KY 《Archives of virology》1999,144(3):601-612
Summary.  Nested polymerase chain reaction (PCR) amplifying the morphological transforming region II (mtrII) of cytomegalovirus (CMV) has been shown to be useful in the detection of CMV DNA in bone marrow transplant (BMT) recipients. However, there has never been any report on mutation hot spots and subtypes of this open reading frame. Using primers derived from sequences upstream and downstream of mtrII (ORF 79), CMV DNA from peripheral blood leukocytes (PBL) and conventional CMV culture of 16 BMT recipients were amplified by PCR, cloned into pUC118, and sequenced. The amino acid sequences were predicted using the standard triplet code. The DNA sequences obtained from direct amplification of CMV in PBL obtained from the 16 patients were 100% identical to the corresponding ones obtained by amplification of CMV DNA extracted from conventional CMV culture. Within mtrII (ORF 79), hot spot single base mutations were observed at positions +40 (G→A), +123 (A→G), +213 (T→C), and +219 (T→C). However, because of third base degeneracy, only amino acid 14 was changed from valine to isoleucine in the predicted protein of 13 patients. This corresponded to the hot spot mutation at position +40 (GTC→ATC), while the rest were silent mutations. An insertion of 3 bases (ACG) was observed in the CMV DNA of 10 patients at positions +91 to +93, leading to a threonine insertion at amino acid 31 in these patients. For patient no. 147 there was a 65 bp deletion in the CMV DNA amplified later in the course of BMT as compared with that early in the course. This gave rise to a frame shift mutation and a change of more than 70% in the predicted amino acid sequence of the protein. Accepted October 14, 1998 Received May 20, 1998  相似文献   
90.
The atypical teratoid/rhabdoid tumor, primary to the central nervous system, is a highly malignant and aggressive neoplasm of infancy and childhood. Although having distinct biological features and clinical outcomes, it is frequently misdiagnosed as primitive neuroectodermal tumor/medulloblastoma. To further distinguish the underlying pathogenesis and to identify biological markers for clinical use, an atypical teratoid/rhabdoid tumor-derived cell line was established and its gene expression pattern analyzed in comparison to the human astrocyte SVG12 cell line and the human DAOY medulloblastoma cell line using a complementary DNA microarray method. The osteopontin gene was found specifically upregulated in atypical teratoid/rhabdoid tumor cells. This specificity was confirmed by immunohistochemistry in pathological sections of tissues from atypical teratoid/rhabdoid tumor patients. Even though the role of osteopontin in the cytopathogenesis of atypical teratoid/rhabdoid tumor still needs to be determined, our data support that overexpressed osteopontin is a potential diagnostic marker for atypical teratoid/rhabdoid tumor.  相似文献   
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