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371.
An old adage in anthropology holds that societies perpetuate their moral codes by the manner in which people raise their children, but socialization is far more than the straightforward passing on of culture. Rather, culture acquisition is a highly conflictual process, rich in contested meanings. What other theorists have shown on the level of cultural systems, this analysis intends to show at the level of micro-interactive processes. The article examines Samoan child-rearing routines, subjective reactions to these routines, the manner in which these reactions are in conformity and in resistance to cultural norms, and the discourse through which Samoan society finally strives to temper the resisting subject. By taking the conflictual dimensions of the socialization process into account, the article describes and analyzes indigenous perspectives on Samoan temperament. These perspectives have the potential to reconcile certain vehement disagreements that characterize the ethnography of the self in Samoa. 相似文献
372.
Different plant parts varied in copper sulfate (CuSO(4)) and cadmium sulfate (CdSO(4))-induced ethylene production, inflorescences showed the greatest induction, while all other plant parts tested produced significantly less. Leaf age had a dramatic effect on CuSO(4) and CdSO(4)-induced ethylene production with the youngest leaves showing the greatest stimulation and as the age of the leaf increased there was a reduction in their ability to produce ethylene. However, there was no significant difference in CuSO(4), CdSO(4) and wound-induced ethylene production when whole rosettes were taken from plants that were 7, 14 or 21-day-old. The highest amount of CuSO(4) and CdSO(4)-induced ethylene production was produced in the root tip with regions below this producing less. CuSO(4) and CdSO(4)-induced ethylene production was also greatest from the tip of the inflorescence to 2cm below the tip and from this point down there was a reduction in ethylene production. When inflorescence stalks or leaves were treated with CuSO(4) or CdSO(4) over a range of concentrations from 0 to 800microM, there was an increase in ethylene production starting at 50microM with increasingly greater responses up to 400microM. There was no further increase at the 800microM CuSO(4) concentration; however, there was a slight decline with 800microM CdSO(4). Inflorescence stalks or leaves treated with either 400microM CuSO(4) or CdSO(4) exhibited a dramatic increase in ethylene production 2h following treatment initiation and remained high over a 24-h period with a decline in ethylene production after this time in inflorescence stalks but not the leaves. It was found that light caused a dramatic decrease in CuSO(4), CdSO(4) and wound-induced ethylene production in both inflorescence stalks and leaves. When inflorescence stalks or leaves were treated at 43 degrees C, there was a dramatic effect on CuSO(4), CdSO(4) and wound-induced ethylene production in each. 相似文献
373.
Muñoz-Aguayo J Lang KS LaPara TM González G Singer RS 《Applied and environmental microbiology》2007,73(17):5421-5425
Antibiotics and antibiotic metabolites have been found in the environment, but the biological activities of these compounds are uncertain, especially given the low levels that are typically detected in the environment. The objective of this study was to estimate the selection potential of chlortetracycline (CTC) on the antibiotic resistance of aerobic bacterial populations in a simulated river water ecosystem. Six replicates of a 10-day experiment using river water in continuous flow chemostat systems were conducted. Each replicate used three chemostats, one serving as a control to which no antibiotic was added and the other two receiving low and high doses of CTC (8 microg/liter and 800 microg/liter, respectively). The addition of CTC to the chemostats did not impact the overall level of cultivable aerobic bacteria (P = 0.51). The high-CTC chemostat had significantly higher tetracycline-resistant bacterial colony counts than both the low-CTC and the control chemostats (P < 0.035). The differences in resistance between the low-CTC and control chemostats were highly nonsignificant (P = 0.779). In general a greater diversity of tet resistance genes was detected in the high-CTC chemostat and with a greater frequency than in the low-CTC and control chemostats. Low levels of CTC in this in vitro experiment did not select for increased levels of tetracycline resistance among cultivable aerobic bacteria. This finding should not be equated with the absence of environmental risk, however. Low concentrations of antibiotics in the environment may select for resistant bacterial populations once they are concentrated in sediments or other locations. 相似文献
374.
Ward SE Johnson CN Lovell PJ Scott CM Smith PW Stemp G Thewlis KM Vong AK Watson JM 《Bioorganic & medicinal chemistry letters》2007,17(18):5214-5217
A series of 5-(piperidinylethyloxy)quinoline 5-HT(1) receptor ligands have been studied by elaboration of the series of dual 5-HT(1)-SSRIs reported previously. These new compounds display a different pharmacological profile with potent affinity across the 5-HT(1A), 5-HT(1B) and 5-HT(1D) receptors and selectivity against the serotonin transporter. Furthermore, they have improved pharmacokinetic profiles and CNS penetration. 相似文献
375.
Evaluating the Effects of Chlortetracycline on the Proliferation of Antibiotic-Resistant Bacteria in a Simulated River Water Ecosystem 总被引:1,自引:0,他引:1
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Jeannette Muoz-Aguayo Kevin S. Lang Timothy M. LaPara Gerardo Gonzlez Randall S. Singer 《Applied microbiology》2007,73(17):5421-5425
Antibiotics and antibiotic metabolites have been found in the environment, but the biological activities of these compounds are uncertain, especially given the low levels that are typically detected in the environment. The objective of this study was to estimate the selection potential of chlortetracycline (CTC) on the antibiotic resistance of aerobic bacterial populations in a simulated river water ecosystem. Six replicates of a 10-day experiment using river water in continuous flow chemostat systems were conducted. Each replicate used three chemostats, one serving as a control to which no antibiotic was added and the other two receiving low and high doses of CTC (8 μg/liter and 800 μg/liter, respectively). The addition of CTC to the chemostats did not impact the overall level of cultivable aerobic bacteria (P = 0.51). The high-CTC chemostat had significantly higher tetracycline-resistant bacterial colony counts than both the low-CTC and the control chemostats (P < 0.035). The differences in resistance between the low-CTC and control chemostats were highly nonsignificant (P = 0.779). In general a greater diversity of tet resistance genes was detected in the high-CTC chemostat and with a greater frequency than in the low-CTC and control chemostats. Low levels of CTC in this in vitro experiment did not select for increased levels of tetracycline resistance among cultivable aerobic bacteria. This finding should not be equated with the absence of environmental risk, however. Low concentrations of antibiotics in the environment may select for resistant bacterial populations once they are concentrated in sediments or other locations. 相似文献
376.
Erik Bannert Tanja Tesch Jeannette Kluess Hana Valenta Jana Frahm Susanne Kersten Stefan Kahlert Lydia Renner Hermann-Josef Rothkötter Sven Dänicke 《Mycotoxin Research》2017,33(3):183-195
This study aimed to investigate a potential modulatory effect of E. coli lipopolysaccharide (LPS) on the kinetics of deoxynivalenol (DON) and zearalenone (ZEN) after pre- or post-hepatic LPS administration to unravel the putative role of the liver. Fifteen barrows were fed a diet containing mycotoxin-contaminated maize (4.59 mg DON/kg feed, 0.22 mg ZEN/kg feed) for 29 days and equipped with pre-hepatic catheters (portal vein, “po”) and post-hepatic catheters (jugular vein, “ju”), facilitating simultaneous infusion of LPS (“LPS group”, 7.5 μg/kg body weight) or 0.9% sterile NaCl solution (control, “CON group”, equivolumar to LPS group) and blood sampling. This resulted in three infusion groups, depending on infusion site: CONju-CONpo, CONju-LPSpo, and LPSju-CONpo. On day 29, pigs were fed their morning ration (700 g/pig) (?15 min), and blood samples were collected at regular intervals relative to infusion start. At 195 min, pigs were sacrificed and bile, urine, liquor, and liver samples collected. DON concentrations in jugular and portal blood decreased in both LPS-infused groups, whereas the ZEN concentrations increased, regardless of the treatment site. In liver tissue, a decrease of both toxin concentrations was observed in endotoxaemic pigs as well as a drop in hepatic conjugation, regardless of LPS entry site. In contrast to our hypothesis, DON and ZEN were not differently altered depending on the LPS-entry site. Neither the absorption nor the accumulation of DON and ZEN in different tissues differed significantly between animals which were infused with LPS via either the jugular or portal vein. 相似文献
377.
Mohamed Zommiti Nathalie Connil Jeannette Ben Hamida Mounir Ferchichi 《Probiotics and antimicrobial proteins》2017,9(4):415-424
The probiotic characteristics of Lactobacillus curvatus DN317, a strain isolated from chicken ceca, were evaluated. This strain was selected for study from the isolated Lactobacillus strains because it has specific anti-microbial activity against Campylobacter jejuni ATCC 33560, Camp. jejuni NCTC 11168, Listeria monocytogenes ATCC 7644, and Bacillus subtilis ATCC 8633. Lact. curvatus DN317 showed an auto-aggregation percentage of 72% and presented the highest co-aggregation with Lact. monocytogenes ATCC 7644 (68%) compared to B. subtilis ATCC 8633 (45%), Camp. jejuni ATCC 33560 (36%), and Camp. jejuni NCTC 11168 (35%). The data revealed that Lact. curvatus DN317 could survive at 0.25% bile, maintain viability at pH 2.5 for 30 min, produce biosurfactants, and adhere to Caco-2 cells. Quantification of IL-6, IL-8, IL-10, and β-defensin 2 levels shows that Lact. curvatus DN317 induces an increase in IL-8 and β-defensin 2 secretion, while the levels of IL-6 and IL-10 do not change. Lact. curvatus DN317 showed high levels of esterase and cysteine arylamidase activities (5); moderate levels of esterase lipase, β-galactosidase, and α-galactosidase activities (4, 3); and weak levels of leucine arylamidase, valine arylamidase, and acid phosphatase activity (1). Various activities were obtained of α-chymotrypsin, β-glucuronidase, β-glucosidase, and N-acetyl-β-glucosaminidase, which have been associated with intestinal diseases. Lact. curvatus DN317 lowered the cholesterol level in MRS with and without bile. Antibiotic susceptibility tests indicated that DN317 was sensitive to ampicillin, gentamicin, kanamycin, streptomycin, tetracycline, clindamycin, erythromycin, and vancomycin but was resistant to chloramphenicol and ciprofloxacin. These results suggest that Lact. curvatus DN317 could potentially function as a probiotic. 相似文献
378.
Jeannette Yen Jason Brown Donald R. Webster 《Marine and Freshwater Behaviour and Physiology》2003,36(4):307-319
Velocity measurements were performed for the flow field generated by tethered krill Euphausia pacifica. The particle image velocimetry (PIV) technique was used to measure the velocity field in vertical planes aligned with the krill body axis. The krill generates a narrow jet-like flow behind and below the pleopods (roughly 25° below horizontal). The volume of fluid moving at greater than 10% of the maximum velocity near the pleopods is roughly 18 times larger than the volume of the krill. Thus, the hydrodynamic disturbance occupies a significantly larger region than the animal body. Other krill, sensing the flow disturbance, may take advantage of the flow induced by a neighbor to locate a mate or to draft for efficient propulsion. 相似文献
379.
380.