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81.
The finding that expressed emotion is associated with the course of psychiatric disorder has generated a great deal of clinical and research interest in expressed emotion as an important risk factor. Theoretical elucidation of the construct of expressed emotion has lagged considerably behind this interest, however. The authors contribute to a dialogue on what is inside the "black box" called expressed emotion. They argue that cross-cultural research can provide an empirical basis for the theoretical grounding of expressed emotion factors. A comparative approach reveals that the construct of expressed emotion is essentially cultural in nature. The constellation of emotions, attitudes, and behaviors that are indexed by the expressed emotion method represent cross-culturally variable features of family response to an ill relative. Questions surrounding the cultural validity of the construct of expressed emotion, the qualitative dimensions of expressed emotion, and statistically significant cross-cultural variations in expressed emotion profiles are discussed. Finally, the authors provide an outline of diverse (cultural, psychobiological, social-ecological) features of expressed emotion. Anthropological analysis of expressed emotion reveals that although expressed emotion indexes a Pandora's box of diverse features, culture provides the context of variation through which these factors are most productively analyzed. 相似文献
82.
This is a retrospective study of the outcome of surgical procedures in patients who were Jehovah's Witnesses. Over a 75-month period, 58 Jehovah's Witness patients had 78 surgical procedures at the Vancouver General Hospital. Three patients had preexisting anaemia of less than 100 g.L-1 haemoglobin. Postoperative haemoglobin concentration decreased below 50 g.L-1 in three patients. One patient had a postoperative haemoglobin of 34 g.L-1 (haematocrit 10.1 per cent) and survived. One patient died from uncontrollable postoperative haemorrhage. Perioperative morbidity was not uncommon, including significant hypotension (eight cases), cardiac arrhythmias (six), myocardial ischaemia (three), excessive bleeding (four), postoperative nausea or syncope (four), and wound or urinary tract infection (four). 相似文献
83.
Identification of a Thymidylate Synthase Gene within the Genome of Chilo Iridescent Virus 总被引:1,自引:0,他引:1
The thymidylate synthase (TS, EC 2.1.1.45) is essential for the de novo synthesis of dTMP in pro- and eucaryotic organisms. Consequently it plays a major role in the replication of the DNA genome of a cell or a DNA virus. The gene encoding the TS of Chilo iridescent virus (CIV) was identified by nucleotide sequence analysis of the viral genome and was mapped within the EcoRI CIV DNA fragments G and R. Computer assisted analysis of the DNA nucleotide sequence between the genome coordinates 0.482 and 0.489 revealed an open reading frame (ORF) of 885 nucleotides. This ORF was found to encode a polypeptide of 295 amino acid residues (33.9 kDa) that showed significant homologies to known TS of different species including mammals, plants, fungi, protozoa, bacteria, and DNA viruses. The highest amino acid homologies were found between the CIV-TS and the TS of herpesvirus ateles (54.0%), Saccharomyces cerevisiae (51.8%), herpesvirus saimiri (51.0%), rhesus monkey rhadinovirus (50.7%), mouse (50.5%), rat (50.2%), varicella-zoster virus (50.2%), equine herpesvirus 2 (50.0%), and the human TS (48.4%). The CIV-TS contains six amino acid domains that are highly conserved in the TS of other species. Within these domains the major amino acid residues are present for which a functional role has been reported. The CIV-TS was found to be more closely related to the TS of eucaryotes than to the TS of procaryotes indicating the phylogenetic origin of the CIV-TS gene. The identification of a TS gene in the genome of CIV is the first report of a viral TS that is not encoded by a herpesvirus or a bacteriophage. 相似文献
84.
Joncourt F Neuhaus B Jostarndt-Foegen K Kleinle S Steiner B Gallati S 《Human mutation》2004,23(4):385-391
Recently developed PCR systems offer online-monitoring of amplification and allow simple and reliable DNA quantification. We have used the LightCycler system to develop a simple and rapid method for direct identification of female carriers of deletions and duplications in the dystrophin gene. The challenge resides in the ability to identify the presence of a deleted or duplicated allele over the background contributed by the normal allele. Quantification is based on the determination of the ratio between potentially deleted/duplicated dystrophin exons and non-deleted/-duplicated reference exons using the unspecific dsDNA-dye SYBRgreen I. In a retrospective study, we evaluated our method in female relatives of DMD/BMD patients with known carrier status by comparative analysis of deleted or duplicated versus non-deleted/-duplicated exons. Carrier status was accurately attributed in 100% of cases, the mean ratios being 0.52+/-0.12 for deletion carriers (expected value: 0.5) and 1.56+/-0.18 for duplication carriers (expected value: 1.5) vs. 1.022+/-0.17 for non-carriers (expected value: 1.0). The method proved to be simple, rapid, reliable, and cost-effective. It may be used for direct determination of deletions/duplications in potential DMD/BMD carriers and may easily be adapted for other genetic conditions involving deletions and duplications. 相似文献
85.
Michael C. Stevens Kristin R. Laurens Peter F. Liddle Kent A. Kiehl 《International journal of psychophysiology》2006,60(3):292-303
Event-related potential (ERP) studies have shown that the neural systems engaged during performance of oddball tasks are sensitive to contextual manipulations, such as the number of stimulus classes. Some ERP components (i.e., N1) are modulated by the number of stimulus types, while others (i.e., P3) are not greatly affected. However, little is known about how these contextual manipulations affect the hemodynamics underlying oddball processing. The purpose of this study was to examine the hemodynamic correlates of target stimulus processing in single-tone (targets alone) and two-tone (targets and standard tones) auditory oddball tasks. The primary hypothesis was that processing of salient stimuli in both contextual conditions would engage the same spatially distributed cortical and subcortical networks observed in previous oddball fMRI studies. Results were consistent with this hypothesis and suggest that the brain engages many potentially useful brain regions during salient stimulus processing despite the low probability that said regions are necessary for task performance, which likely reflects a form of “adaptive reflexive processing”. Results were also consistent with ERP data that shows that the N1 is larger for single-tone tasks by showing greater amplitude of hemodynamic response for single-tone targets, relative to two-tone targets, in bilateral temporal cortex and bilateral inferior lateral frontal cortex. The results are discussed as they relate to the understanding of neurocognitive function pertaining to contextual manipulations in general, and orienting processes in particular. 相似文献
86.
Raymond G. Goodwin Wenie S. Din Terri Davis-Smith Dirk M. Anderson Steven D. Gimpel Timothy A. Sato Charles R. Maliszewski Camilynn I. Brannan Neal G. Copeland Nancy A. Jenkins Terry Farrah Richard J. Armitage William C. Fanslow Craig A. Smith 《European journal of immunology》1993,23(10):2631-2641
4-1BB is an inducible T cell antigen that shows sequence homology to members of an emerging family of cytokine receptors, including those for tumor necrosis factor and nerve growth factor. To aid in the analysis of the function of 4-1BB we have utilized a soluble form of the molecule as a probe to identify and clone the gene which encodes its ligand. The ligand for 4-1BB is a type II membrane glycoprotein that has homology to tumor necrosis factor, lymphotoxin, and the ligands for CD40 and CD27, all of which are themselves ligands to receptors in this superfamily. The gene for 4-IBB is on mouse chromosome 4 and maps close to the p80 form of the tumor necrosis factor receptor as well as the gene for CD30. The gene for 4-IBB ligand maps to mouse chromosome 17, but considerably distal to the tumor necrosis factor and lymphotoxin genes. Interaction of 4-1BB with its ligand induces the proliferation of activated thymocytes and splenic T cells, a response which is mimicked on similar cell populations stimulated with an antibody to 4-1BB. 相似文献
87.
Wilson R Moore J Jenkins C Miller H Maclean MA McInnes IB Walker JJ 《Human reproduction (Oxford, England)》2003,18(7):1529-1530
BACKGROUND: Immunological abnormalities have been found in pregnant women with a history of recurrent miscarriage. This study compared interleukin-2 receptor (IL-2R) levels in non-pregnant women with a history of recurrent miscarriage with those found in serum from a non-pregnant group with no such history. METHODS: Group 1 comprised 49 non-pregnant women with a history of recurrent miscarriage (at least three consecutive miscarriages). Group 2 comprised 22 non-pregnant women with no history of miscarriage. Serum IL-2R levels were measured in all patients. RESULTS: The results obtained showed that although all women were not pregnant at the time of sampling, IL-2R levels were significantly higher in women in Group 1 compared with those in Group 2 (1589 +/- 1289 versus 1082 +/- 823 pg/ml; P < 0.05). Follow-up data were available for 21 women from Group 1. The next pregnancy ended successfully for 14 of these women, while seven miscarried again. The IL-2R levels obtained pre-pregnancy were not significantly different between the two groups (1480 +/- 910 versus 1356 +/- 716 pg/ml). CONCLUSION: This study has shown that non-pregnant women with a history of recurrent miscarriage have raised IL-2R levels. These increased pre-pregnancy IL-2R levels did not necessarily predict miscarriage for the next pregnancy. 相似文献
88.
Fayer R Trout JM Lewis EJ Xiao L Lal A Jenkins MC Graczyk TK 《Parasitology research》2002,88(11):998-1003
Although Cryptosporidium has been found worldwide in molluscan shellfish from waters contaminated with human and animal feces, little or no related environmental data have been obtained. In the present study, oysters ( Crassostrea virginica) were collected eight times over 3 years from seven sites in the Chesapeake Bay or its tributaries, with accompanying data on water temperature, salinity, rainfall, and streamflow. Oyster gill washings were examined by immunofluorescence microscopy for Cryptosporidium oocysts. Of 1,590 oysters collected, 19.6% had detectable oocysts. Of 53 collections, oocysts were detected 81% of the time. The time when the greatest percentage of oysters at most sites had detectable oocysts coincided with the time of greatest weekly and monthly rainfall, greatest streamflow into the Bay, and lowest water temperatures. In 28% of 53 collections, C. parvum genotypes 1 and 2 and C. baileyi were identified by PCR and gene sequencing. Oocyst infectivity was confirmed from 37.5% of 40 collections by initiating C. parvum genotype 2 infections in mice. 相似文献
89.
Onchocerca volvulus larval antigen, OvB20, induces partial protection in a rodent model of onchocerciasis.
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OvB20 is an antigen of Onchocerca volvulus preferentially recognized by sera from cattle vaccinated with irradiated infective larvae of Onchocerca lienalis. Antibodies raised against the recombinant protein were used to characterize the expression of the native protein in different developmental stages of O. volvulus and the rodent filaria Acanthocheilonema viteae. In O. volvulus, antibodies reacted to a polypeptide of 42 kDa in microfilariae and with proteins of 52 and 65 kDa in third-stage larvae. No products were detected in adult stages. Immunogold electron microscopy localized the native protein to discrete patches of the hypodermis and cuticle of infective larvae. Characterization of a homologous protein in A. viteae confirmed the stage-specific expression in infective larvae of the 65-kDa protein, which was secreted during in vitro culture. Vaccination of rodents against A. viteae with a B20-maltose-binding-protein fusion protein resulted in a 49 to 60% reduction in adult worm recoveries with a corresponding 97% reduction in microfilaremia. 相似文献
90.
High responsiveness of HLA-B57-restricted Gag-specific CD8+ T cells in vitro may contribute to the protective effect of HLA-B57 in HIV-infection 总被引:1,自引:0,他引:1
Jansen CA Kostense S Vandenberghe K Nanlohy NM De Cuyper IM Piriou E Manting EH Miedema F van Baarle D 《European journal of immunology》2005,35(1):150-158
HLA-B57 has been shown to be associated with long-term asymptomatic HIV-1 infection. To investigate the biological mechanism by which the HLA-B57 allele could protect from HIV-1 disease, we studied both the number of CD8(+) T cells as well as CD8(+) T cell responsiveness directed to different HIV-1 Gag peptides presented by HLA-A2, -B8 or -B57. T cells specific for the HLA-B57 peptide KAFSPEVIPMF responded more readily and to a higher extend to antigenic stimulation in vitro than T cells specific for the HLA-A2 peptide SLYNTVATL or the HLA-B8 peptide EIYKRWII. This phenomenon was reproducible with T cells from individuals expressing HLA-B57 in combination with one or both of the other alleles and was persistent during long-term follow-up. Lower reactivity of A2- and B8-restricted T cells was not explained by mutations in the B8- or A2-restricted Gag-peptides. Moreover, no correlation between peptide mutation frequency and IFN-gamma production by the corresponding Gag-specific T cells was observed. In conclusion, functional differences were observed between T cells specific for HIV epitopes derived from the same protein presented by different HLA molecules. B57-restricted KAFSPEVIPMF-specific CD8(+) T cells have relatively high responsiveness, which could contribute to the protective effect of HLA-B57 in HIV infection. 相似文献