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101.
Summary The influence of GA on the mitotic activity of each zone of the shoot apex is studied in two species having strikingly different morphogenetic responses to the chemical.InRudbeckia bicolor, the stimulation of mitoses mostly occurs in the central zone. This fact is related to the subsequent flowering of the plant. InPerilla nankinensis, the activation is more general and affects the central and the peripheral zones. It is connected to an acceleration of the plastochronic functioning.Therefore, the action of GA differs following the species and following the meristematic zones.In the pith, no increase of the length of the cells is apparent in either case, but the mitotic activity is enhanced. This increase of the number of cell divisions provokes the bolting ofRudbeckia and the elongation ofPerilla.With 1 Figure in the Text 相似文献
102.
Loeding E Thomas J Bernier D Santymire R 《Journal of applied animal welfare science : JAAWS》2011,14(3):220-246
Introductions of sable antelope (Hippotragus niger) can be difficult due to the potential ensuing aggression compounded by their large horns. The goal was to use hormonal assays and behavioral analyses to evaluate the success of an introduction of 2 adult females at Lincoln Park Zoo. The objectives were to (a) document behavioral and hormonal changes in 2 female sable antelope during the introduction, (b) compare fecal glucocorticoid metabolites (FGM) in each individual during the introduction stages, (c) measure fecal androgen metabolites (FAM) during introduction and compare with dominance rank and observed aggression, and (d) monitor estrous cycle synchronization. Results demonstrate that FGM were higher before than during and after the introduction. Behavioral observations indicated limited aggression between females, although the keeper survey results revealed that the new female was more dominant and had higher mean FGM and FAM than the resident. Both sable antelope were reproductively active throughout the year. Results indicate that fecal hormone analysis can provide zoo management with valuable information to minimize the risk of aggression, injury, and stress during introductions of nonhuman animals. 相似文献
103.
Global analysis of in vivo Foxa2-binding sites in mouse adult liver using massively parallel sequencing 总被引:1,自引:0,他引:1
104.
S A Rabbani S M Kaiser J E Henderson S M Bernier A J Mouland D R Roy D M Zahab W L Sung D Goltzman G N Hendy 《Biochemistry》1990,29(43):10080-10089
Recombinant analogues of human parathyroid hormone [hPTH-(1-84)] were expressed in Escherichia coli harboring plasmids containing synthetic genes under the control of the lac promoter. The level of expression of the gene encoding the truncated analogue, hPTH-(3-84), was greater than that of the gene encoding full-length hPTH-(1-84) but less than that of the gene encoding proparathyroid hormone (hProPTH). This may be due in part to the relative efficiency of translation of the mRNA as suggested by secondary structure analysis and in part because of enhanced stability of the extended peptide. Formylmethionyl derivatives of hProPTH and of hPTH-(3-84) and underivatized hPTH-(3-84) were purified by HPLC, and their identity was confirmed by NH2-terminal sequencing and amino acid analysis. The bioactivity of these recombinant peptides was then tested in skeletal and renal adenylate cyclase assays in vitro and in assays examining effects on plasma and urine calcium and phosphate levels and on urine cyclic AMP levels in vivo. The NH2-terminally extended analogue fMet-hProPTH displayed 10% of the in vitro activity of hPTH-(1-84) and was a partial agonist in vivo. The peptides hPTH-(3-84) and fMet-hPTH-(3-84) were inert in vitro and were very weak in vitro antagonists when compared to the NH2-terminal analogue bovine [Nle8,18Tyr34]PTH-(3-34)-NH2. In vivo, hPTH-(3-84) and the bPTH-(3-34) analogue, when assayed at a 10:1 molar ratio relative to bPTH-(1-84), were each inert, and neither demonstrated antagonist activity at these concentrations.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
105.
106.
The complex of ciliary neurotrophic factor-ciliary neurotrophic factor receptor alpha up-regulates connexin43 and intercellular coupling in astrocytes via the Janus tyrosine kinase/signal transducer and activator of transcription pathway 下载免费PDF全文
Ozog MA Bernier SM Bates DC Chatterjee B Lo CW Naus CC 《Molecular biology of the cell》2004,15(11):4761-4774
107.
Background
Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India 相似文献108.
In many cases of interspecific kleptoparasitism, hosts developdefensive behaviors to minimize the impact of kleptoparasites.Because vigilance and defensive behaviors are often costly,selection should favor hosts that adjust the amount of investmentneeded to minimize losses to kleptoparasitism. However, examplesof such facultative responses are rare. Here, we investigatethe response of cooperatively breeding pied babblers (Turdoidesbicolor) to the drongo (Dicrurus adsimilis), an avian kleptoparasitethat regularly follows pied babbler groups, often giving alarmcalls to alert the group to predators but also occasionallygiving false alarm calls in order to steal food items. We showthat pied babbler response to drongos varies markedly accordingto babbler group size. In small groups, where there are fewindividuals available to act as sentinels, babblers sentinelless when a drongo is present and respond strongly to drongoalarm calls. However, in large groups, where there are manyindividuals available to participate in predator vigilance,babblers sentinel more often when a drongo is present, rarelyrespond to drongo alarm calls, and aggressively displace drongos,with a consequent decline in the number of successful kleptoparasitismevents. This behavior represent a facultative response to akleptoparasite according to the costs versus benefits of toleratingtheir presence. 相似文献
109.
Generation of anti-idiotypic and anti-anti-idiotypic monoclonal antibodies in the same fusion. Support of Jerne's Network Theory 总被引:1,自引:0,他引:1
J Hébert D Bernier Y Boutin M Jobin W Mourad 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(11):4256-4261
Upon immunization of mice with a mAb (290A-167) directed against an epitope of Lol p I (the major allergenic determinant of Lolium perenne), both anti-idiotypic (aId) mAb (Ab2) and anti-aId mAb (Ab3) were produced. The Ab2 displayed the following internal image properties of Lol p I: it can be affinity-purified on an immobilized Id column; its binding to the anti-Lol p I mAb (290A-167) is inhibited by Lol p I; it inhibits in a dose-response fashion the binding of the specific Id to Ag. It is recognized by anti-Lol p I antisera from different species such as mouse, human, and goat. The Ab3 which binds to Lol p I was also produced from the same fusion. This binding was inhibited significantly by aId mAb (Ab2), anti-Lol p I mAb (290A-167) and Lol p I. These data indicate that the two mAb with specificity for Lol p I (290A-167 and Ab3) share similar reactivity to the Ag and that aId mAb is the internal image of the epitope recognized by the Id. We showed also that the capacity of rabbit aId Ab directed against the 290A-167 Id to inhibit the binding of Ab1 and Ab3 to Ag was almost abolished by passage over a Ab3-coated Sepharose column. This would suggest that not only are the two mAb with reactivity to Lol p I (Ab1 and Ab3) directed against identical epitopes, but that they in fact shared identical idiotopes as well. The production of identical mAb upon immunization with either the Ag or the aId mAb supports that the conceptual framework proposed by Jerne finds its biologic application in the course of an immune response. 相似文献
110.
Dolman KM Brouwer N Frakking FN Flatø B Tak PP Kuijpers TW Førre O Smerdel-Ramoya A 《Arthritis research & therapy》2008,10(2):R32