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71.
The production of mycotoxins by Alternaria alternata in cellulosic ceiling tiles was examined with thin-layer chromatography and high-performance liquid chromatography procedures.
Alternariol and alternariol monomethyl ether were found in ceiling tile extracts, whereas extracts of control rice cultures
of all three isolates produced these mycotoxins plus altenuene and altertoxin I. Extensive fungal growth and mycotoxin production
occurred in the ceiling tiles at relative humidities of 84–89% and 97%.
Received 28 May 1997/ Accepted in revised form 06 October 1997 相似文献
72.
目的:改进现有的细胞冷冻保存方法,建立一个不舍二甲基亚砜(DMSO)和血清(FBS)的高效冷冻保存方法,为细胞治疗等临床实践提供优质细胞。方法:海藻酸微囊包埋鼠胚成纤维细胞(STO细胞)后用不含DMSO和FBS的冷冻保存液进行冷冻保存。,设四个对照组:添加10%DMSO和20%FBS的组、仅添加10%DMSO的组、仅添加20%FBS、DMSO和FBS均不添加组。在冷冻前后对各实验组细胞用台盼兰染色,进行细胞计数,计算细胞存活率,同时利用溴乙锭的二聚物(EthD)、钙黄绿素-AM(Calcein—AM)进行染色观察细胞的形态,且进一步验证细胞存活率;解冻复苏后用MTT法评估细胞的增殖速度和生长活力。结果:冷冻保存30天后对各组的细胞数量、细胞存活率、细胞形态和解冻复苏后细胞的生长活力进行比较发现,海藻酸微囊包埋冷冻组的细胞数、细胞存活率、细胞形态和生长活力均与添加DMSO和FBS的组之间无显著性差异,而与其它三个对照组呈显著性差异。结论:使用海藻酸微囊替代DMSO和FBS保存STO细胞,能有效的维持细胞形态、数量、存活率,同时不影响细胞的生长活力,从而建立了一个不含DMS0和FBS的高效冷冻保存方法。 相似文献
73.
几种旱生灌木种子萌发对干旱胁迫的响应 总被引:55,自引:5,他引:55
以不同渗透势的PEG(6 0 0 0 )溶液 (- 0 .3~ - 2 .7MPa)为模拟干旱胁迫条件 ,研究了柠条 (Caraganakorshinskii)、花棒 (Hedysarumscoparium)和白沙蒿 (Artemisiasphaerocephala)种子发芽、幼苗生长和累积吸水率对干旱胁迫的响应 ,讨论了参试种子发芽特性、初生根长度与幼苗建植成活率的关系 .结果表明 ,干旱胁迫下柠条发芽率最高 ,其次为花棒 ,白沙蒿最低 . - 0 .3~ - 0 .6MPa渗透势下白沙蒿发芽 10d的初生根长度显著大于花棒和柠条 (P <0 .0 5 ) ,三者的测量值依次为 7.9、4 .5和 3.1cm .干旱胁迫条件下参试种子发芽率与种子 72h累积吸水率均呈极显著的正相关 (P <0 .0 1) . 相似文献
74.
Myrmecophilous butterflies utilise ant–treehopper associations as visual cues for oviposition 下载免费PDF全文
1. Selection of a safe oviposition site is important for herbivorous insects whose immature stages have limited mobility. Female herbivores rely on environmental cues for this choice, and presence of natural enemies or mutualistic partners may be important in this process. 2. Some butterflies have mutualistic interactions with ants (myrmecophily), in which caterpillars offer a nutritional liquid and gain protection against natural enemies. Participants in butterfly–ant mutualisms may utilise signals to initiate interactions, but the use of visual cues by ovipositing myrmecophilous butterflies remains uncertain. 3. Larvae of facultatively myrmecophilous Parrhasius polibetes (Lycaenidae) feed on Schefflera vinosa, and females prefer to oviposit near aggregations of the ant‐tended treehopper Guayaquila xiphias, where caterpillars survive better due to increased ant attendance. Given the conspicuousness of ant–treehopper associations, it was investigated whether butterflies use them as visual cues for oviposition and, if so, which participants of the association are used as cues: ants, treehoppers, or both. 4. Experiments using dried insects on paired branches revealed that females visually recognise ants and ant–treehopper associations, using them for egg‐laying decisions. However, presence of a treehopper aggregation alone had no effect on oviposition choices. 5. This is a first insight into the importance of visual discrimination for ovipositing myrmecophilous butterflies. The results show that facultative mutualisms can be important enough to promote a behavioural adaptation (visual detection of ants) reinforcing the interaction. Our research highlights the importance of the behavioural interface within complex multispecies systems. 相似文献
75.
Conventional methods for histological preparation of degenerated myelin are time-consuming and difficult. The purpose of our study was to shorten the time required for the procedure and to obtain better quality results for light microscopic demonstration of degenerated myelin in the central and peripheral nervous systems by using microwave irradiation. Rat brain and sciatic nerve were used for the study. The middle cerebral artery was occluded and the sciatic nerve was cut to produce myelin degeneration. Marchi's method was used for staining degenerated myelin. Fixation for light microscopy that would take two days using the conventional procedure was completed in 16.5–18.5 min using microwave irradiation. While staining of degenerated myelin requires 10 days for the conventional Marchi method, we decreased it to 7 h for brain tissue and 1 h for sciatic nerve by using the microwave oven. Moreover, a better quality preparation was achieved in the groups stained under microwave irradiation than those prepared by the conventional method. 相似文献
76.
Apurva S. Chitre Oksana Polesskaya Katie Holl Jianjun Gao Riyan Cheng Hannah Bimschleger Angel Garcia Martinez Tony George Alexander F. Gileta Wenyan Han Aidan Horvath Alesa Hughson Keita Ishiwari Christopher P. King Alexander Lamparelli Cassandra L. Versaggi Connor Martin Celine L. St. Pierre Jordan A. Tripi Tengfei Wang Hao Chen Shelly B. Flagel Paul Meyer Jerry Richards Terry E. Robinson Abraham A. Palmer Leah C. Solberg Woods 《Obesity (Silver Spring, Md.)》2020,28(10):1964-1973
77.
A Västermark JA Jacobsson A Johansson R Fredriksson U Gyllensten HB Schiöth 《Journal of genetics》2012,91(2):237-240
78.
Background
Perturbations in cell-cell interactions are a key feature of cancer. However, little is known about the systematic effects of cell-cell interaction on global gene expression in cancer. 相似文献79.
Isabel La Rosa Luiz SA Camargo Michele M Pereira Rafael Fernandez-Martin Dante A Paz Daniel F Salamone 《Reproductive biology and endocrinology : RB&E》2011,9(1):18
Background
BMP4 is a member of the transforming growth factor beta (TGFbeta) superfamily and Noggin is a potent BMP inhibitor that exerts its function by binding to BMPs preventing interactions with its receptors. The aim of this work was to investigate the role of BMP4 and Noggin, on oocytes in vitro maturation (m experiments) and embryos in vitro development (c experiments) of bovine. 相似文献80.
The present study was conducted primarily to determine the occurrence of polypharmacy in patients with schizophrenia on risperidone. The secondary aim was to ascertain the incidence of inappropriate prescribing with anticholinergics. A retrospective review of the medical records of all patients who were being followed up at the out-patient clinic of a tertiary-care hospital in Malaysia was conducted. Only patients who were being prescribed risperidone between 1 June 2008 and 31 December 2008 were included in the study. Demographic data such as patient’s age, gender and race were obtained from the patient’s medical records. In total, 113 patients met the selection criteria. Polypharmacy was found to occur in 34 patients (30.09%), with the majority (76.47%) being on two antipsychotics. In total, 27 patients (34.18%) on monotherapy with risperidone were prescribed an anticholinergic on scheduled dosing, while 19 patients (24.05%) were prescribed it on an as-needed basis. Of the patients on polypharmacy, 26 (76.47%) were on scheduled dosing of anticholinergics, while three (8.82%) were taking the medication on an as-needed basis. Polypharmacy should be avoided, and the use of anticholinergics should be closely reviewed. By adopting more efficient prescribing practices, costs can be reduced and financial resources can instead be channelled towards more beneficial areas for the patients. 相似文献