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21.
An experimental competitive enzyme-linked immunosorbent assay (morbillivirus cELISA) using a recombinant N antigen (rRPV N) expressed in a baculovirus and a ruminant morbillivirus (RPV and PPRV)-specific monoclonal antibody (P-13A9) was developed for simultaneous detection of rinderpest virus (RPV) and peste des petits ruminants virus (PPRV) antibodies and its diagnostic performance was evaluated. A set of known reference antisera against RPV and PPRV belonging to different lineages, experimental sera from cattle vaccinated for a RPV of Asian lineage, and field sera from cattle and sheep/goat populations known to be positive (West Africa) and negative (Korea) for RPV and PPRV were used for the evaluation. Morbillivirus cELISA results on the panel of experimental RPV and PPRV antisera showed high correlation (r=0.97) between the whole virus and the rRPV N antigens, suggesting that the rRPV N contains a ruminant morbillivirus-specific antigenic determinant recognized by the P-13A9 and it may be suitable as an ELISA antigen in place of the whole virus. Morbillivirus cELISA detected anti-RPV and anti-PPRV antibodies in all reference RPV and PPRV antisera containing VN titers >/=1:8, suggesting that the assay can simultaneously detect antibodies against RPV and PPRV. Anti-RPV antibody was detected by morbillivirus cELISA in vaccinated cattle as early as the VNT and continued to be detectable by both the cELISA and the VNT until termination of the study. When applied to field samples from Africa, morbillivirus cELISA showed good agreement with a RP cELISA kit (kappa value of 0.86) in bovine sera and with a peste des petits ruminant cELISA kit (kappa value of 0.81) in caprine/ovine sera. Usefulness of morbillivirus cELISA using the rRPV N protein was discussed.  相似文献   
22.
HSV-1 B capsids are composed of seven major proteins, designated VP5, VP19C, 21, 22a, VP23, VP24, and VP26. VP indicates that the capsid protein is also a component of the infectious virion. Capsid proteins 21, 22a, and VP24 are specified by a single open reading frame (UL26) that encodes 635 amino acids. An objective of the work in our laboratory is to identify and map interactions among and between capsid proteins. In the present studies we employed the yeast GAL4 two-hybrid system developed by Fields and his colleagues (Nature 240, 245-246 (1989)) for this purpose. DNA corresponding to the capsid open reading frames was derived as a PCR product and fused to sequences of the GAL4 activation and DNA binding domains. Using this system each of the capsid proteins has been tested for interactions with all of the other capsid proteins. Three interactions have been identified: a relatively strong self-interaction between 22a molecules (residues 307-635 of UL26), bimolecular interactions between 22a and VP5, and another between VP19C and VP23. The interactions were detected by the expression of beta-galactosidase enzyme activity, and yielded 289, 86, and 63 units of enzyme activity, respectively. For the 22a self-interaction, elimination of residues 611-635 resulted in an approximately twofold decrease in enzyme activity. The C-terminal 25 amino acids of 22a were also essential for the bimolecular interaction between 22a and VP5.  相似文献   
23.
The effects of batrachotoxin (BTX) on cloned alpha-subunit Na+ channels were examined in CHO-K1 cells (a chinese hamster ovary cell line) transfected with rat brain NaIIA cDNA. Under whole-cell patch clamp conditions, BTX shifted the voltage dependence of the activation process by about 45 mV towards the hyperpolarizing direction and eliminated the inactivating phase of Na+ currents. Repetitive depolarizations greatly facilitated the binding of BTX with NaIIA channels while the membrane was held at -100 mV. In chloramine-T-pretreated cells, the association rate of BTX binding with the NaIIA channel was 6.5-fold faster than that in untreated cells. The estimated association rate constant for BTX binding with the open form of NaIIA channel was 1.11 x 10(6) mol-1.s-1 at room temperature. BTX-modified NaIIA channels were blocked by tetrodotoxin (TTX) in a complicated manner. First, the TTX binding to the closed state of BTX-modified NaIIA channels was not voltage dependent. The KD value of TTX was measured at 8.9 nM, which was similar to that of unmodified channels (KD = 14.2 nM). Second, the block of the open state of BTX-modified NaIIA channels by TTX was voltage dependent; depolarization reduced the potency of TTX block between -20 mV to +50 mV. Below -30 mV, the TTX affinity began to level off, probably because of the increased presence of the closed state. Unexpectedly, steady-state inactivation of BTX-modified NaIIA channels was minimal as measured by the two-pulse protocol, a phenomenon distinctly different from that found in GH3 cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
24.
An initial Bentall operation was performed on a patient aged 38 years with annuloaortic ectasia and aortic regurgitation. An echocardiogram and RI angiogram revealed a perigraft aortic aneurysm on the same patient aged 45 years. The aneurysm gradually developed and the maximum diameter reached 90 mm in size. The Redo-Bentall operation (Piehler modification) was successfully done once again on the same patient aged 56 years. The anastmosis between the right coronary orifice and the graft was detached on all sides. The anastmosis between the left coronary orifice and the graft was detached two thirds of all sides.  相似文献   
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The production of the cognitive internal state word know by four 2- to 5-year-old children and their parents was examined. The levels of meaning of cognitive words can be categorized hierarchically along the dimensions of conceptual difficulty and abstractness (see Booth & Hall, 1995). The present study found that children and their parents expressed low levels of meaning less frequently, whereas they expressed high levels of meaning more frequently as a function of age. The children's use of know was also correlated positively with (1) their number of different words produced suggesting that cognitive words are related to more general semantic processes, and (2) with parental use of those same cognitive words suggesting that parental linguistic input may be an important mechanism in cognitive word acquisition. Finally, young children tended to use know more to refer to themselves than to refer to others, whereas their parents tended to use know equally to refer to self and others. The importance of cognitive words in a theory of language acquisition is discussed.  相似文献   
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AIM: To examine the association of Epstein-Barr virus (EBV) with carcinoma of the ear. METHODS: Five non-keratinising squamous cell carcinomas and two undifferentiated carcinomas of the ear were examined. In situ hybridisation was used to localised EBV-encoded RNAs (EBER). Immunohistochemical methods to detect LMP-1 and EBNA2 were performed in the EBER positive cases. RESULTS: Two cases were EBER positive, including one non-keratinising and one undifferentiated carcinoma. Both showed identical morphology to those arising from the nasopharynx, with abundant lymphoid stroma. They were both negative for LMP-1 and EBNA2. CONCLUSIONS: EBV associated carcinoma with the morphology of lymphoepithelioma can also arise from the middle ear.  相似文献   
30.
Depression following childbirth (postpartum depression) is a common psychiatric illness of women, postpartum. We review Japanese and English literature on postpartum depression. Problems with definition, study design and validity of the diagnosis prevented comprehensive understanding whether postpartum depression is a distinct subtype of endogenous depression. In general, postpartum depression seems to be the same illness as depression at other times in life. The biological and psycho-social pathogenetic factors, unique to the puerperal period, are not yet known. Clinicians caring for women and infants should learn to screen their patients for this multifactorial (genetic, temperamental, and environmental) disorder, and try to integrate a multidisciplinary (pharmaco-, psycho-, socio-, familial) approach.  相似文献   
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