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81.
Neokadsuranic acid A, which is the first triterpenoid with the 14(13-->12) ABEO lanostane skeleton, was isolated from KADSURA HETEROCLITA together with (24 Z)-3-oxo-lanosta-8,24-dien-26-oic acid. The present paper deals with the isolation and structure elucidation of these two new compounds.  相似文献   
82.
Previous studies have suggested that facial displays in the presence of others are influenced by the relationship with accompanying persons. In these studies, subjects participated with friends or strangers, without any focus on social interactions between partners. In the current study, pairs of friends or strangers viewed film clips expected to elicit positive and negative affects; the control group participated without partners. We measured synchronous smiles between partners as a social interactive display, in addition to the duration and the frequency of smiles and frowns. Subjective emotion and social motive were also measured. Smiles were facilitated by the presence of a friend than a stranger or the condition of lone participation, regardless of stimulus valence. Synchronous smiles and the communication motive were also enhanced with a friend than with a stranger. These results suggested that the expression of smiles was facilitated by the communication motive and social interactions between partners.  相似文献   
83.
The K-variant of butyrylcholinesterase (BCHE-K) recently has been reported to be associated with Alzheimer disease (AD) in carriers of the epsilon4 allele of the apolipoprotein E (APOE) gene. We have re- examined the frequency of the BCHE-K allele in a large data set of both sporadic and familial cases of AD disease, and we have also examined the segregation of three genetic markers on chromosome 3 near BCHE . Our data neither support an association of BCHE-K with sporadic or familial AD, nor do they suggest the existence of another gene nearby on chromosome 3 as a common cause of familial AD.   相似文献   
84.
We used proteins in rat lung lavage fluid to successfully produce an antiserum against Clara cell secretory products. When used with the immunoperoxidase method, the antiserum specifically stained cells of the bronchiolar lining, which are morphologically consistent with Clara cells, as well as a few columnar cells in the bronchial and tracheal mucosa. B-5-fixed lung tissue furthermore demonstrated the immunoreactive layer over the bronchiolar epithelium. The alveolar and bronchial lining layers, on the other hand, were not immunoreactive, although a trace of granular immunoreactivity was seen in the latter. It was suggested that Clara cells produce and secrete some proteinaceous materials, which are mainly localized in the bronchiolar area after secretion and are seldom transferred into the alveolar lining layer. Our antibody cross-reacted with the Clara cells of mice, but not with those of hamsters, guinea pigs, rabbits, dogs, cats, monkeys, and man. The high degree of specificity of this antisera to Clara cells in formalin-fixed materials should make it a valuable tool for identifying Clara cell change in non-neoplastic lung pathology and in obtaining some insights into cell origin in neoplastic diseases.  相似文献   
85.
BACKGROUND: Exposure to acute stressors modulates both innate and acquired immune function. However, little is known about whether stress has the potential to modulate the pathogenesis of allergic rhinitis. OBJECTIVES: To determine the effects of acute restraint stress on the initiation of allergic rhinitis in a murine model. METHODS: CBA/J mice were repeatedly intranasally sensitized with phospholipase A2 (PLA2) from honeybee venom without adjuvant. Restraint stress was applied using uniform cylinders once a week for a continuous 8-hour period, on five occasions in total. Production of PLA2-specific antibodies and degree of nasal and blood eosinophilia were compared between stressed and control mice. RESULTS: Repeated intranasal sensitization with PLA2 induced PLA2-specific IgE and marked eosinophilia in both the nose and blood in CBA/J mice. Exposure to restraint stress significantly inhibited production of PLA2-specific IgE, IgG1 and IgG2a. Conversely, the stress exerted no significant effect on eosinophilia. CONCLUSIONS: Exposure to acute restraint stress inhibits antigen-specific antibody production, but not local or systemic eosinophilia. The results of this study suggest that acute stress has the potential to modulate the initiation of allergic rhinitis.  相似文献   
86.
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   
87.
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   
88.
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   
89.
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   
90.
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   
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