Think of each sentence as representing one of the following “codes” based on its
function: 根据功能，每个句子分别代表以下“代码”
B = Background information 背景信息
P = Principal activity/purpose/scope/aims of study 主要活动/目的/范围/研究目标M = Information about methodology 方法
F = Main findings/results 重要发现/结果
C = Main implications/conclusions of the work 重要意义/研究结论
S = Suggestions/recommendations 提示/建议
*Tip: B, P, M, F, China Science!
Adapted from Weissburg and Buker (1994)
Stimulus-induced oscillations in plant cell cytosolic free calcium. Ca2+ is implicated as asecond messenger in the response of stomata to a range of stimuli. [B1-well focused intro toresearch topic]However, the mechanism by which stimulus-induced increases in guard cellcytosolic free Ca2+([Ca2+] are transduced into different physiological responses remains to beexplained. [B2-gap in understanding] Oscillations in [Ca2+] may provide one way in which this canoccur. [B3-hypothesis] We used photometric and imaging techniques to examine this hypothesis inguard cells of Commelina communis. [P, M1-NB active rather passive]. External Ca2+ ([Ca2+]e),which causes an increase in [Ca2+], was used as a closing stimulus. [M2] The total increase in [Ca2+]was directly related to the concentration of [Ca2+]e, both of which correlated closely with thedegree of stomatal closure. [F1]Increases were oscillatory in nature, with the pattern of thdegree theoscillations being dependent on the concentration of [Ca2+]e. [F2] At 0.1 mM, [Ca2+]e inducedsymmetrical oscillations. In contrast, 1.0 mM [Ca2+]e induced asymmetric oscillations. [F3]Oscillations were stimulus-dependent and modulated by changing [Ca2+]e.[F4] Experiments usingCa2+ channel blockers and Mn2+-quenching studies suggested a role for Ca2+ influx during theoscillatory behavior without excluding the possible involvement of Ca2+ release from intracellularstores. [C1] These data suggest a mechanism for encoding the information required to distinguishbetween a number of different Ca2+-mobilizing stimuli in guard cells, using stimulus-specificpatterns of oscillations in [Ca2+]. [C, S-broader/possible focus for further research]
