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991.
The sequence is presented of RNA-5 of Echinochloa hoja blanca tenuivirus, a second tenuivirus associated with rice cultivation in Latin America (after rice hoja blanca virus). The RNA is 1334 nucleotides long and contains in the complementary sense RNA a single long open reading frame. The deduced amino acid sequence of this open reading frame shows that it encodes a highly basic and hydrophilic 44 kD protein (pc5) with about 50% similarity to the pc5 protein of maize stripe virus (MStV). This and other features of the RNA are discussed.The GenBank accession number of the sequence reported in this paper is L47430. 相似文献
992.
G. Majella de Jong Irma G. H. Timmerman Paul M. G. Emmelkamp 《Journal of behavioral medicine》1996,19(6):529-542
Hitherto, various critics have claimed that the most commonly used measure for daily hassles is confounded with psychological well-being in both content and format. In order to circumvent such contamination, the Survey of Recent Life Experiences (SRLE) was developed by Kohn and MacDonald (1992). In the present study, the SRLE was psychometrically evaluated within a general sample of the Dutch population. Confirmatory factor analysis showed that, with the exception of one item, the original six-factor structure was strongly replicated. For five of six factors, internal consistency reliabilities proved satisfactory. It is argued that the rather low internal consistency reliability of the sixth factor may be improved if additional items are subjoined. In addition, yielded relationships between the SRLE and other variables were in accordance with previous research. It is therefore argued that the results are in support of cross-cultural construct validity of the SRLE. Future use within other Western European societies is recommended. 相似文献
993.
VanderZee KI Sanderman R Heyink JW de Haes H 《International journal of behavioral medicine》1996,3(2):104-122
The reliability and validity of the RAND 36-Item Health Survey 1.0 were investigated in a population sample of 1,063 inhabitants of a Dutch township, all age 17or older. Confirmatory factor analysisonly partly supported the internal structure of the RAND 36-Item Health Survey 1.0. The internal consistency of the instrument was high. Pointing to high convergent validity, a multitrait-multimelhod matrix revealed that the RAND-36 scales showed higher correlations with corresponding scales from other instruments than with noncorresponding scales. However, indicating low discriminant validity, some of these correlations did not exceed the intercorrelations among the RAND-36 scales. Multivariate analysis of variance (MANOVA) showed significant effects of age for physical functioning, role limitations (physical problem), general health perception and pain, and significant effects of education on physical functioning and general health perception. Significant sex differences were found for mental health only. The results of this study on the psychometric properties of the RAND 36-Item Health Survey 1.0 seem promising. There is a need for further studies investigating its factor structure and cross-cultural equivalence. 相似文献
994.
Verhell Coleta; de Graaff Graaff Esther; Bakker Cathy E.; Willemsen Rob; Willems Patric J.; Meijer Nicolle; Galjaard Hans; Reuser Arnold J.J.; Oostra Ben A.; Hoogeveen Andre 《Human molecular genetics》1995,4(5):895-901
FMR1 protein expression was studied in different tissues. Inhuman, monkey and murine tissues, high molecular mass FMR1 proteins(6780 kDa) are found, as shown in lymphobiastoid celiiines. The identity of these proteins was confirmed by theirabsence in tissues from patients with the fragile X syndromeand a FMR1 knock-out mouse. An IIe367Asn substitution in theFMR1 protein did not aiter the transiation, processing and localizationof FMR1 proteins in lymphoblastoid cells from a patient carryingthis mutation. All the high molecular mass FMR1 proteins isolatedfrom normal lymphoblastoid cells and cells from the patientwith the IIe367Asn substitution were able to bind RNA. However,the FMR1 proteins of the patient had reduced affinity for RNAbinding at high salt concentrations. In some human, monkey andmurine tissues low molecular mass FMR1 proteins (3941kDa) were found, which had the same N terminus as the 6790kDa isoforms, but differ in their C terminus and are thereforemost likely the result of carboxy-terminal proteolytic cleavage.These low molecular mass FMR1 proteins did not bind RNA, incontrast with the high molecular mass FMR1 proteins. The significanceof these low molecular mass proteins remains to be studied. 相似文献
995.
M Rits P S Hiemstra H Bazin L A Van Es J P Vaerman M R Daha 《European journal of immunology》1988,18(12):1873-1880
The ability of rat monoclonal IgA, specific for 2,4-dinitrophenyl (DNA), to activate the complement (C) system of the rat was investigated using aggregated IgA or IgA immune complexes (IC). IgA was coated onto a solid phase, and tested for its capacity to bind C3 upon incubation at 37 degrees C in normal rat serum (NRS) in the presence of Mg-EGTA. Binding of C3 was observed dependent on the dose of dimeric (d-), polymeric (p-) and secretory IgA tested. In contrast, little C3 fixation was observed in this system with monomeric (m-) rat IgA or with mouse m- and d-IgA (MOPC315). Soluble and insoluble rat IgA IC were prepared using dinitrophenylated rat serum albumin (DNP8RSA) as antigen (Ag), and assessed for C activation. It was shown that insoluble IC (immune precipitates; IP) containing m-, d- or pIgA of rat origin activate the alternative pathway of rat C, as demonstrated by their capacity to induce C consumption in NRS in the presence of Mg-EGTA. When p- and m-IgA IP were compared for their capacity to activate C, it was found that p-IgA activated C four times as efficiently as m-IgA IP (at 2 mg/ml). Soluble rat IgA IC were prepared in an excess of DNP8RSA, fractionated by gel filtration on Sepharose 6B, and analyzed for C activation and antibody (Ab)/Ag ratio. In contrast to m-IgA IP, soluble m-IgA did not activate C. On the other hand soluble d-IgA IC activated C dependent on their concentration and size: at a concentration of 0.1 mg/ml high-molecular weight d-IgA IC with a high Ab/Ag ratio were four times as efficient as low-molecular weight IC with a low Ab/Ag ratio, and twice as efficient as IP prepared at equivalence. To demonstrate the induction by IgA of the assembly of the terminal membrane attack complex, trinitrophenyl (TNP)-conjugated rat red blood cells (TNP-RRBC) coated with d- or p-IgA were shown to be lysed in NRS in the presence of Mg-EGTA. No lysis of m-IgA-coated TNP-RRBC was observed. The results in this study demonstrate that both soluble and insoluble rat IgA IC activate the alternative pathway of homologous rat C. Alternative pathway activation by soluble rate IgA IC is dependent on the size of the IC. The degree of polymerization of the IgA Ab itself also influences C activation. 相似文献
996.
P Klück F J Ten Kate A W Van der Kamp D Tibboel J C Molenaar 《American journal of clinical pathology》1986,86(4):490-492
Until now, no pathologic explanation could be found for the postoperative obstipation occurring in some patients with intestinal aganglionosis. Twenty-two of 108 infants treated for intestinal aganglionosis suffered from postoperative obstipation. Resected material from these 22 patients and from 17 control subjects was investigated with monoclonal anti-neurofilament antibody staining. An abnormal staining pattern was revealed in 18 of the constipated patients. Consequently, this new immunohistochemical staining technic has revealed a hitherto unsuspected cause for postoperative obstipation in aganglionosis. The monoclonal antibody may provide early warning of such postoperative constipation. 相似文献
997.
I. Zimmermann B. A. Peskar W. T. Ulmer A. A. Bugalho de Almeida 《Inflammation research》1984,15(3-4):153-161
The effects of Hi and ACH aerosol and of intravenous infusion of compound 48/80 on bronchoconstriction and plasma levels of Hi, TXB2, KH2PGF2 and KH2PGE2 were investigated in 11 bastard dogs. Administration of Hi and ACH aerosol induced bronchoconstriction accompanied by an increase in the plasma levels of Hi and TXB2. No effect on the plasma levels of KH2PGF2 and KH2PGE2 was detected. Release of endogenous Hi by compound 48/80 induced bronchoconstriction and significant increases in the plasma levels of TXB2 as well as of KH2PGF2 and KH2PGE2. The effects of a second administration of Hi and ACH aerosols after compound 48/80 did not differ qualitatively from the effects of the first aerosol administration. However, quantitatively, the second Hi aerosol induced significantly less bronchoconstriction and TXB2 release. Similarly, effects of the second ACH aerosol tended to be decreased as compared to the first ACH aerosol, although the difference was not significant. The diminished effect of the agonists could be due to receptor desensibilization and/or release of adrenaline, which in turn decreases bronchoconstriction and eicosanoid release. 相似文献
998.
Intracellular rubella virus (RV) polypeptide synthesis during a productive infection of murine fibroblasts (L2 cells) has been investigated using immune precipitation techniques. Four structural and three additional intracellular polypeptides (p75, p60, VP44, VP41, p30, VP24, and VP19) were observed following polyacrylamide slab gel electrophoresis and autoradiography. However, when normal rat glial (RG) cells were infected only five polypeptides could be observed (p75, p60, VP44, VP41, and VP19). No infectious RV could be detected in tissue culture medium from flasks of infected RG cells. Calculations of relative concentrations of intracellular RV polypeptides precipitated from L2 and RG cells indicated that undetectable amounts of p30 and VP24, diminished amounts of p60 and VP19 and more than twice as much p75 were precipitated from infected RG cells. These data indicate that there is restricted replication of RV in normal rat glia. 相似文献
999.
1000.
Functional insights on the polarized redistribution of leukocyte integrins and their ligands during leukocyte migration and immune interactions 总被引:4,自引:2,他引:4
Olga Barreiro Hortensia de la Fuente María Mittelbrunn Francisco Sánchez-Madrid 《Immunological reviews》2007,218(1):147-164
Summary: Cell–cell and cell–matrix interactions are of critical importance in immunobiology. Leukocytes make extensive use of a specialized repertoire of receptors to mediate such processes. Among these receptors, integrins are known to be of crucial importance. This review deals with the central role of integrins and their counterreceptors during the establishment of leukocyte–endothelium contacts, interstitial migration, and final encounter with antigen-presenting cells to develop an appropriate immune response. Particularly, we have addressed the molecular events occurring during these sequential processes, leading to the dynamic subcellular redistribution of adhesion receptors and the reorganization of the actin cytoskeleton, which is reflected in changes in cytoarchitecture, including leukocyte polarization, endothelial docking structure formation, or immune synapse organization. The roles of signaling and structural actin cytoskeleton-associated proteins and organized membrane microdomains in the regulation of receptor adhesiveness are also discussed. 相似文献