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51.
The inhibitory effects of various ion channel blockers were examined on in vitro excystment of Paragonimus ohirai metacercariae induced by a bile salt, sodium cholate. At a concentration of 10 µM, bepridil, a non-selective Ca2+ channel blocker, completely inhibited in vitro excystment, whereas TEA, lidocaine, and R(+)-IAA-94, channel blockers against K+, Na+ and Cl ions, respectively, benzamil, an Na+/H+ and Na+/Ca2+ ion exchanger blocker, and R(+)-DIOA, a [K+, Cl] cotransporter inhibitor, did not. Considering the previous result that Ca2+ ionophores are also efficient inducing factors for in vitro excystment of P. ohirai metacercariae and the present result, bile salts appear to induce the excystment of P. ohirai metacercariae through evoking the Ca2+ channels of target cells within the metacercarial juveniles.  相似文献   
52.
The aim of this study is to develop a technical quality evaluation system of electroencephalogram (EEG) recording in order to acquire technically satisfactory EEG records, which may contribute to the accuracy improvement of EEG interpretation. In our developed system, the evaluation of EEG recording comprises the detection of technical artifacts and physiological status, which indicates the recording status objectively. In addition, the caution signals to users are generated in the system according to the undesired status detected. The information displayed to users includes the updated EEG records and instant evaluation results. Two examples of evaluation results are introduced in this paper, illustrating unsatisfactory records and artifact free records, respectively. The experimental results are proposed to verify the effectiveness of the technical quality evaluation of EEG recording. The implementation of the technical quality evaluation of EEG recording is helpful to acquire technically satisfactory EEG records, which may improve the accuracy of results in both the visual and the automatic EEG interpretation, and ease the laborious work of EEG technicians in the recording progress.  相似文献   
53.
Previous developmental studies on the temporomandibular joint (TMJ) have proposed several hypotheses on the formation of its articular cavity. However, detailed information is meager. The present study examined the formation process of the articular cavity in the rat TMJ by immunocytochemistry for CD31, RECA-1, and ED1, which are useful cellular markers for endothelial cells and monocyte/macrophage lineages, respectively. The upper articular cavity formation had begun by embryonic day 21 (E21) and was completed at postnatal day 1 (P1) in advance of the lower cavitation; the latter took place from P1 to P3. The occurrence and distribution pattern of the CD31-, RECA-1-, and ED1-positive cells differed between the upper and lower articular cavity-forming areas: the ED1-positive cells exclusively occurred in the area of the prospective upper articular cavity prior to its formation, while no ED1-positive cell appeared in the lower cavity-forming area. In contrast, the CD31- and RECA-1-positive endothelial cells were restricted to the lower cavity-forming area (never the prospective upper cavity) at E19 and diminished thereafter. Throughout the cavity formation, we failed to find any apoptotic cells in the cavity formation area, indicating no involvement of apoptosis in the cavity formation in TMJ. The present findings on the behaviors of endothelial cells and ED1-positive cells show a possibility of different mechanism in the cavity formation between the upper and lower articular cavities in the rat TMJ. The appearance of ED1-reactive cells and temporal vascularization may play crucial roles in the upper and lower articular cavity formation, respectively.  相似文献   
54.
The concept of antiphospholipid syndrome(APS) has been widely accepted. Antiphospholipid antibodies originally included anticardiolipin antibodies and lupus anticoagulants as serological marker of APS. However, recent advances have shown that most pathogenic antiphospholipid antibodies are directed to phospholipid binding proteins such as beta 2-glycoprotein I and prothrombin as well as phospholipids. The preliminary classification criteria for definite APS have been advocated as the "Sapporo criteria". Further prospective investigations are required to re-evaluate the clinical significance of so-called antiphospholipid antibodies.  相似文献   
55.
Allergens present in the excretory/secretory (ES) products of adult Paragonimus ohirai were biochemically identified. Immunoblot analysis using sera from P. ohirai-infected rats revealed only two allergens to be major proteins in the ES products, with apparent molecular masses (M(r)) of 27 and 29 kD. As the ES products contained a high proportion of acidic and neutral cysteine proteinases, we examined whether or not the allergens and the cysteine proteinases were identical. The acidic and neutral cysteine proteinases were biochemically purified from the ES products and showed M(r) of 27 and 29 kD, respectively. The two cysteine proteinases had almost identical N-terminal amino acid sequences and were reactive with specific IgE in sera from the infected rats. The allergenicity of the cysteine proteinases was confirmed by 48-hour homologous passive cutaneous anaphylaxis. Immunoblot and immunocapture assays using anti-human IgE monoclonal antibody showed that the proteinase allergens were reactive with specific IgE of patients with paragonimiasis westermani. Also, the cysteine proteinases were reactive with specific IgG of both the infected rats and the patients. Therefore the acidic and neutral cysteine proteinases prepared from the ES products of P. ohirai will be useful allergens and antigens for the immunodiagnosis of paragonimiasis.  相似文献   
56.
Environmental fungi, in particular primary pathogens and Cryptococcus spp. can be responsible for skin lesions mimicking sporotrichosis. In this paper, we report a case of subcutaneous cryptococcosis in an apparently healthy, young male patient due to a non-C. neoformans Cryptococcus species, C. diffluens. The isolate showed in vitro phenotypic switching that may affect virulence and host inflammatory and immune responses, and in vitro resistance to amphotericin B and 5-flucytosin. This species shares several phenotypic traits with C. neoformans, and, therefore, decisive diagnosis should be based on biopsy and culturing results followed by molecular identification.  相似文献   
57.
58.
Summary.  Following establishment, via the vaginal route, of infection with an AP-1 binding-site deleted mutant (ΔAP-1) of feline immunodeficiency virus (FIV), cats were challenged with a homologous intact strain (TM2) of FIV. The cats were observed for 23 weeks to evaluate the efficacy of the ΔAP-1 against the homologous TM2 strain challenge. These two viruses were differentiated by Southern blotting after amplification of proviral DNA by semi-nested polymerase chain reaction in DNAs of peripheral blood mononuclear cells and tissues. A TM2-specific band was detected in one cat exposed to but not infected with ΔAP-1, but not in two ΔAP-1-infected. These results indicate that ΔAP-1 could protect against subsequent challenge with homologous FIV TM2 strain. Received December 23, 1998 Accepted March 31, 1998  相似文献   
59.
The lysosome-associated membrane proteins (LAMPs)-1 and -2 are major constituents of the lysosomal membrane. These molecules are known to be among the most glycosylated proteins of several types of cells and cancer cells, and their expression in cancer cells is marked by a distinct difference in the structures of the oligosaccharides as compared to nonmalignant cells. We analyzed by immunohistochemistry the intensity and distribution of LAMP-1 and LAMP-2 in 9 human colorectal cancer cases and in 16 control cases, including inflammatory diseases (diverticulitis, ulcerative colitis, and Crohn's disease). LAMP proteins were expressed more intensely in the epithelium of colorectal neoplasms than in normal mucosa (P < 0.05), and no significant differences were found between adenoma and cancer cells (P > 0.05) in the same tissue section. Further, in sites of inactive inflammatory diseases and nonneoplastic areas in cancer specimens, no significant increases in epithelial LAMP proteins were observed, even in the proliferative zone of the lower crypt epithelium. Northern blot analysis showed increased expression of LAMP-1 and LAMP-2A in two of three colorectal cancers examined and increased LAMP-2B in all three cancers. Our findings suggest that LAMPs are related to neoplastic progression, but there is no direct association between the expression of LAMP molecules and cell proliferation.  相似文献   
60.
Localization of glycosaminoglycans (GAG) in Bruch's membrane of postnatal rat eyeballs was examined histochemically. Fixed eyeballs from postnatal rats (ages 5 days and 8 weeks) were routinely processed and embedded in paraffin wax or Quetol 651 resin. Paraffin-embedded tissue sections were stained with hematoxylin and eosin or sensitized high iron diamine procedure in combination with selective methods such as GAG-degrading enzyme digestions and/or a chemical modification, and examined by light microscopy. Quetol 651-embedded ultrathin sections were stained with heavy metals and examined by electron microscopy. In rats at postnatal day 5, Bruch's membrane contained mainly chondroitin sulfate (CS) and heparan sulfate (HS). In contrast, at 8 weeks after birth the membrane included a large amount of dermatan sulfate (DS) and HS. According to electron microscopic findings, Bruch's membrane on day 5 consisted of only 3 layers without a central elastic layer. However, at 8 weeks after birth the membrane was constructed of 5 layers. These findings suggested that the difference in GAG molecular species in the membranes at 5 days and at 8 weeks after birth could be correlated with the development and maturation of the collagenous layer in Bruch's membrane. Moreover, maturation of Bruch's membrane may contributes to the architectural stabilization of the outer portions of the photoreceptor cells.  相似文献   
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