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71.
Recently we have shown that the major antigenic sites of bovine serum albumin exhibit functional equivalence progessively increasing with the time at which antibodies are obtained after the first immunization. Analysis of our recent immunochemical findings and the known covalent structure of bovine serum albumin have enabled us to predict the locations of five antigenic sites of bovine serum albumin. The predicted locations were synthesized, and immunochemical studies with late-course antisera showed them to constitute antigenic sites of native bovine serum albumin.  相似文献   
72.
Summary The proboscis extension reponse of the blowfly during stimulation of the tarsal sugar receptors was inhibited by the presence of NaCl. Acceptance thresholds for sucrose in various concentrations of NaCl were measured. The median acceptance thresholds for sucrose in mixtures of 0.01, 0.25, 0.5 and 1.0 M NaCl were 1.8 × 10–3, 6.0 × 10–3, 1.2 × 10–2, and 2.0 × 10–2 M, respectively. Concentration-response curves for sucrose in the tarsal D-type sugar receptor shifted to the right under the existence of high concentration of NaCl. Number of impulses per D-type sugar receptor at the median acceptance thresholds described above were 7.5, 8.4, 6.8 and 10.4 for the first 0.1 s of stimulation, respectively. The average number was 8.2 impulses per 0.1 s. Comparisons were made between the behavioral acceptance thresholds (1) on one leg exposed to sucrose mixed with 0.01 M NaCl and (2) on two contralateral legs, one of which was exposed to sucrose in 0.01 M NaCl and the other to 0.5 M NaCl alone. The acceptance thresholds from two experiments agreed with each other. The median threshold value was 1.7 × 10–2 M sucrose. Behavioral inhibition by NaCl in mixtures with sucrose can be explained by its peripheral inhibition of sugar receptors.This research was supported in part by ITO foundation and Scientific Research Fund from the Ministry of Education of Japan.  相似文献   
73.
Taka amylase A glycopeptide (TA-GP) strongly inhibited the interaction of antimannan (antibodies directed towards mannan from Saccharomyces cerevisiae) with yeast mannan, whereas ovalbumin glycopeptide (OA-GP) did so only poorly. We inferred that this is due to the strong reactivity of antimannan with terminal trimannosides composed of Manα1→2Man or Manα1→3Man linkages which occur in mannan and TA-GP. In contrast, TA-GP and OA-GP were nearly equally reactive with concanavalin A having the ability to interact with terminal mannose and 2-0-mannose residues which occur abundantly in these glycopeptides. Thus, antimannan should be useful as a probe for characterizing glycoproteins from extracellular fluids or cellular membranes.  相似文献   
74.
Polarographic studies on oxidation-reduction components bound with chromatophores from Rhodospirillum rubrum were carried out at 24 degrees. 1. Using a carbon-paste electrode as the working electrode, polarographic waves characteristic of oxidation-reduction components were observed in the presence, but not in the absence of Triton X-100; these waves were therefore measured in the presence of the detergent. 2. At least two kinds of oxidation-reduction components were detectable, having different half-wave potentials (E1/2); at pH 7, one had an E1/2 value of +275 mV (POC+275) and the other had a value of +60 mV (POC+60). 3. POC+275 was reduced by succinate and by NADH. Both reductions were almost completely inhibited by antimycin A, which hardly affected the reductions of ubiquinone-10 by succinate and by NADH. Most POC+275 molecules were not reduced by the substrates when quinones were extracted from the chromatophores, and the reductions were mostly restored when ubiquinone-10 was re-added. This indicates that POC+275 is functional between ubiquinone-10 and cytochrome c2 in the electron transport system. 4. POC+60 was reduced by succinate, but hardly at all by NADH. The reduction of POC+60 was not influenced either by the addition of antimycin A or by the extraction of quinones. This suggests that POC+60 is functional in the process from succinate dehydrogenase [EC 1.3.99.1] to ubiquinone-10 in the electron transport system. 5. Of the POC+275 reducible by dithionite, approximately 70% could be reduced in the absence of Triton X-100, provided that the potential of the working electrode immersed in chromatophore suspensions was set at potentials of 0 mV or lower and that the electrochemical reaction was carried out at pH 7.5. When the potential of the electrode was set at +50 mV (the same as the E1/2 value of ubiquinone-10 bound with chromatophores), and the suspension was allowed to stand for various lengths in the presence of the detergent, it was found that approximately half of the electrochemically reducible POC+275 was rapidly reduced, followed by a slow reduction. The discrepancy in the oxidation-reduction equilibrium on the basis of the E1/2 values of ubiquinone-10 and POC+275 is discussed.  相似文献   
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Bordetella bronchiseptica strains isolated from the nasal cavities of young pigs in Japan from 1969 to 1972 were surveyed for drug resistance and distribution of R factors. Of 304 strains examined, 71 (23%) were resistant to either one or more of following three drugs, streptomycin (SM), sulfadimethoxine (SA), and aminobenzyl penicillin (APC). Triple (SM.SA.APC)-resistance was most frequent among these resistant strains. Strains of double (SM. SA)- or single (SM)- and (SA)-resistance were also isolated, but were very few in numbers. Of the 71 drug-resistant strains, 61 (86%) were found to carry R factors which were capable of conjugal transfer. All of these R factors had the triple (SM.SA.APC)-resistant markers and were identified as fi (no fertility inhibition) type. The (SM.SA.APC)-resistant strains carrying R factors had been isolated from pigs reared on various farms in different districts, and consequently the prevalence of B. bronchiseptica strains carrying R factors was considered to be relatively wide-spread in young pigs.  相似文献   
78.
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017.  相似文献   
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Given their sessile nature, land plants must use various mechanisms to manage dehydration under water‐deficit conditions. Osmostress‐induced activation of the SNF1‐related protein kinase 2 (SnRK2) family elicits physiological responses such as stomatal closure to protect plants during drought conditions. With the plant hormone ABA receptors [PYR (pyrabactin resistance)/PYL (pyrabactin resistance‐like)/RCAR (regulatory component of ABA receptors) proteins] and group A protein phosphatases, subclass III SnRK2 also constitutes a core signaling module for ABA, and osmostress triggers ABA accumulation. How SnRK2 is activated through ABA has been clarified, although its activation through osmostress remains unclear. Here, we show that Arabidopsis ABA and abiotic stress‐responsive Raf‐like kinases (AtARKs) of the B3 clade of the mitogen‐activated kinase kinase kinase (MAPKKK) family are crucial in SnRK2‐mediated osmostress responses. Disruption of AtARKs in Arabidopsis results in increased water loss from detached leaves because of impaired stomatal closure in response to osmostress. Our findings obtained in vitro and in planta have shown that AtARKs interact physically with SRK2E, a core factor for stomatal closure in response to drought. Furthermore, we show that AtARK phosphorylates S171 and S175 in the activation loop of SRK2E in vitro and that Atark mutants have defects in osmostress‐induced subclass III SnRK2 activity. Our findings identify a specific type of B3‐MAPKKKs as upstream kinases of subclass III SnRK2 in Arabidopsis. Taken together with earlier reports that ARK is an upstream kinase of SnRK2 in moss, an existing member of a basal land plant lineage, we propose that ARK/SnRK2 module is evolutionarily conserved across 400 million years of land plant evolution for conferring protection against drought.  相似文献   
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