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11.
Serum IgE levels in rats infected with Paragonimus westermani] 总被引:1,自引:0,他引:1
Paragonimus westermani is a common fluke in Korea. The present study aimed to determine serum total IgE and specific IgG levels in experimental paragonimiasis of rats. Each Wistar rat was inoculated orally with 20-25 metacercariae of P. westermani from Cambaroides similis. Before and after infection (1, 2, 3, 4, 6, 8 weeks) of P. westermani, the blood was collected from the retro-orbital venous plexus of rats and kept serum at -70 degrees C. Serum total IgE and specific IgG levels were determined by the capture and conventional enzyme-linked immunosorbent assay, respectively. The results were as follows; 1. Serum IgE values were increased to 0.18 +/- 0.042 at 2 weeks, 0.28 +/- 0.151 at 4 weeks and 0.43 +/- 0.055 at 8 weeks after infection. The absorbances of non-infected rats ranged 0.07 +/- 0.021-0.12 +/- 0.025. 2. Specific IgG values were slightly increased at 3 weeks (0.20 +/- 0.032) and gradually increased up to 8 weeks (0.31 +/- 0.067) after infection. The absorbances of non-infected rats ranged 0.11 +/- 0.035-0.18 +/- 0.019. The present results suggested that P. westermani could elevate serum IgE and specific IgG antibodies in Wistar rats which were not a good definitive host. 相似文献
12.
A single-stage two-flap method of total ear reconstruction 总被引:2,自引:0,他引:2
A single-stage two-flap method of total ear reconstruction in congenital microtia is reported. This method was derived from the one-stage reconstruction described by Song and Song. Two flaps defined by vascular basis were elevated on the mastoid area: the superficial skin flap supplied mainly by subcutaneous pedicled arteriole perforators from the posterior auricular artery and the deeper axial-pattern fascial flap including the posterior auricular artery itself. The ear framework, exaggeratedly carved using autologous rib cartilage, could be inserted easily between the two flaps, simultaneously producing the auriculocephalic angle and the conchal wall. Intraoperative expansion of the skin flap and postoperative external ear molding also were performed to create aesthetically pleasing ears. 相似文献
13.
The F2 progeny of a cross between a chromosome 2 multiple marker stock and an adapted cultivar of barley were analyzed for four
morphological markers and electrophoretic patterns of eight leaf isozymes. TheIdh-2 locus was linked to thePer-5 locus (27.96±5.07 cM) and to thee locus (10.26±3.13 cM). Also, thePer-5 ande loci were located on the short arm of chromosome 2. In additionIdh-2 was also located on barley chromosome 2 and was linked to thev locus (13.18±3.56 cM), which is located on the long arm of chromosome 2. Two other marker genes,li andwst,,B, were linked (26.50±5.24 cM) on chromosome 2 but segregate independently of the other loci evaluated.
This project was supported by funds from the U.S.-Spain Joint Committee for Scientific and Technological Cooperation. 相似文献
14.
Heterogeneity of adrenocortical ferredoxin 总被引:1,自引:0,他引:1
Bovine adrenocortical ferredoxin (adreno-ferredoxin) was purified from adrenocortical mitochondria by an improved method that included hydrophobic chromatography on Toyopearl gels. The purified ferredoxin was electrophoretically homogeneous. It was further separated into five fractions by hydrophobic chromatography on a TSK-gel phenyl-5PW column with a high-pressure liquid chromatography system. The properties of the three main fractions were examined. The fractions had identical absorption spectra and almost the same activity in an NADPH-cytochrome c reducing system. Their amino-terminal sequences all corresponded to the reported sequence, but the carboxyl-terminal residues were glycine or serine, not alanine as reported. These results indicate that these adreno-ferredoxins had additional amino acid residues at the carboxyl end. It seems that adreno-ferredoxin extracted from mitochondria undergoes proteolytic attack during purification to become heterogeneous. 相似文献
15.
Role of endogenous complement in monoclonal IgM antibody-dependent leukemia suppression in vivo: participation of C3b 总被引:1,自引:0,他引:1
R J Johnson H Kaizer A G Massey H S Shin 《Journal of immunology (Baltimore, Md. : 1950)》1985,134(5):3497-3503
The mechanism by which McAb of the IgM isotype causes prolonged survival of leukemic rats was investigated. The participation of endogenous C in the suppression of IgM-sensitized leukemia cells was demonstrated by the observations that a) suppression was abrogated in CVF-treated rats, and b) the CVF effect was partially reversed if C3b was provided on the surface of IgM-sensitized leukemia cells. 相似文献
16.
C. A. Batt M. T. Follettie H. K. Shin P. Yeh A. J. Sinskey 《Trends in biotechnology》1985,3(12):305-310
The coryneforms are a diverse group of bacteria which includes animal and plant pathogens as well as non-pathogenic bacteria. Although they are of significant economic and health importance, their genetics is poorly understood. The development of genetic engineering techniques for coryneforms and initial gene cloning studies are discussed. 相似文献
17.
Summary Short-term effects of CaCl2-treatment on parathyroid cells of the rat, especially on their storage granules, were studied at the ultrastructural level. After an injection of 4% CaCl2, serum calcium levels (SCL) rapidly increased from 9.1 mg/dl (controls) to a maximum of 14.9 mg/dl at 20 min. At 5 min after the injection, the number of type-I storage granules (large core) [NSG-I] and that of type-II storage granules (small core) [NSG-II] remained unchanged, in spite of elevated SCL (12.4 mg/dl). As soon as SCL rose to 13.2 mg/dl at 7.5 min, NSG-I gradually decreased to a minimum at 30 min; in contrast, NSG-II gradually increased to a maximum at 30 min. Vacuolar bodies also increased together with the augmentation of type-II storage granules. The average diameter of the core of the storage granules decreased significantly after the injection. Protein A-gold method for immunocytochemistry showed that the cores of these granules contain parathormone. Acid-phosphatase activity was occasionally found in storage granules of both types, especially in those of type II. It is concluded (i) that type-I storage granules may be transformed into vacuolar bodies via type-II granules as a result of hydrolysis, and (ii) that these processes may be accelerated during hypercalcemia. 相似文献
18.
Sumitomo Shinichiro Tatemoto Yukihiro Fukui Shin Nakamura Taka-aki Fukushima Shoji Ito Nobuyuki Mori Masahiko 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(1):395-399
Virchows Archiv B Cell Pathology - Paget cells from cases of mammary and extramammary Paget’s disease were examined for carcinoembryonic antigen (CEA) and CEA-related antigens by the... 相似文献
19.
Direct evidence for the existence of nominal antigen binding sites on T cell surface Ti alpha-beta heterodimers of MHC-restricted T cell clones 总被引:15,自引:0,他引:15
R F Siliciano T J Hemesath J C Pratt R Z Dintzis H M Dintzis O Acuto H S Shin E L Reinherz 《Cell》1986,47(2):161-171
The binding of nominal antigen to Ti alpha-beta heterodimers on MHC-restricted human T cell clones specific for fluorescein-5-isothiocyanate (FL) was detected by flow cytometry and affinity chromatography. The FL-Ti interaction is of physiologic significance, since T cell activation is induced by cross-linked arrays of FL in the absence of the specific MHC recognition. High antigen valence is required to achieve stable binding to cells and subsequent activation, which is consistent with estimated Ti-FL association constants of less than 3 X 10(5) l/mol. In addition to providing direct evidence that the Ti alpha-beta heterodimer is the receptor for antigen, these data suggest that nominal antigen binding sites exist on the Ti molecules of at least some MHC-restricted clones. 相似文献
20.
A possible phagocytic role for folliculo-stellate cells of anterior pituitary following estrogen withdrawal from primed male rats 总被引:3,自引:0,他引:3
Summary Ultrastructural changes suggesting a phagocytic role for the nongranular folliculo-stellate cells of the anterior pituitary are investigated in estrogen-primed male rats after withdrawal of estrogen. Morphological changes in mammotropes following the removal of a subcutaneous estradiol-containing Silastic implant include the formation of intracellular lipid bodies. These lipid bodies appear to be associated with enhanced estrogen-dependent prolactin secretion in mammotropes. Seven and 24 h after estrogen withdrawal intracellular lipid within mammotropes seems to be released into the intercellular space. Seventy-two h after estrogen withdrawal, lipid droplets are almost entirely cleared from mammotropes while folliculo-stellate cells become packed with lipid globules. Folliculo-stellate cells also undergo dramatic hypertrophy 7 and 24 h after the removal of E2-containing implants. Extensive intercellular junctions including zonulae adhaerentes, desmosomes, and putative gap junctions are formed. Intercellular junctions delineate extravascular channels into which numerous microvilli project. Folliculo-stellate cells appear capable of accumulating many lipid droplets, presumably related to mammotrope metabolism. What appear to be large secondary lysosomes as well as the lipid droplets are observed within folliculostellate cells; lipid, therefore, may be degraded through a lysosomal pathway in folliculo-stellate cells. 相似文献