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排序方式: 共有257条查询结果,搜索用时 15 毫秒
81.
A rapid epifluorescence staining method using the LIVE/DEAD® BacLight Bacterial Viability kit was applied to differentiate both viable and total counts of acetic acid bacteria in vinegar fermentation. The results obtained were compared with those from other measurement techniques: 4,6-diamidine-2phenyl indole (DAPI) and 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) and colony counts. BacLight total counts were comparable to DAPI (differing by <3.5%). BacLight viable counts were similar to CTC counts but considerable higher than colony-forming cells in plates. 相似文献
82.
TIAN Yi KONG Jie YANG Cuihua 《科学通报(英文版)》2006,51(19):2369-2374
The total yield of shrimp farming industry declined after WSSV broke out. It was only at the last 20 years that production had again begun to increase[1]. So far, shrimp farming industries mostly depend on capturing wild shrimps or wild post-larvae to sto… 相似文献
83.
最小存活种群的确定与生物多样性保护 总被引:9,自引:3,他引:6
以Allee的集群理论为基础,从种群内部的生态学机制出发,把物种划分为补偿物种(compensations species)、中性物种(middle species)与退偿物种(depensation species)三个类别,同时应用数学生态方法进行了种群生存力分析(PVA)的理论探讨,提出了最小存活种群(MVP)与物种濒危度的新观点,最后,对环境保护与生物多样性的保护提出了合理化建议。 相似文献
84.
《Electroanalysis》2017,29(6):1498-1505
In bioelectrochemical systems (BESs), living microorganisms are capable of converting the chemical energy of degradable organic matters into bioelectricity. The electrical current outputs are dependent on the microbial cell viability and the biodegradation rates. Therefore, monitoring the current generative through the BES is promising for the microbial activity assessments. As compared to conventional microbiological methods, BESs are considered as non‐invasive techniques that offer rapid and sensitive detection of cellular functions (extra‐ and/or intracellular). Therefore, several progressions were made in the last 100 years in order to develop effective BESs. In this review, the involvements of materials sciences, microbiology, and electrochemistry in the effective designing and developments of BESs were intensively discussed. Due to the nanotechnology revolutions, manipulation of electrode materials led to the creation of different BES generations. Therefore, the impact of nanomaterials on the developments of the second and third generations of BESs is still the outlook of this promising research area. 相似文献
85.
LUIS F. GORDILLO 《Natural Resource Modeling》2011,24(2):207-221
Abstract The success a species may have invading a patch previously unoccupied is of considerable interest for pest managers and conservation ecologists. The purpose here is to present a mechanistic approach to analyze reproductive Allee effects appearing through the failure in the process of fertilization in a two‐sex population and observe how the survival in an invaded patch is affected. This is in contrast to the usually employed stochastic models with a deterministic skeleton that describe the presence of Allee effects. A Poisson–Ricker model, which includes stochastic demography and sex determination with females classified as successfully fertilized or not fertilized, is used. Numerical approximations to the probabilities of extinction and the mean time to extinction are presented, for fixed parameter values, suggesting how stochasticity in the mating process combined with random fluctuations in the male and female densities, at each generation, contribute to the risk of extinction of a population which started an invasion at a low density. 相似文献
86.
87.
Sylvain Catros Bertrand Guillotin Markéta Ba?ákováJean-Christophe Fricain Fabien Guillemot 《Applied Surface Science》2011,257(12):5142-5147
Biofabrication of three dimensional tissues by Laser-Assisted Bioprinting (LAB) implies to develop specific strategies for assembling the extracellular matrix (ECM) and cells. Possible strategies consist in (i) printing cells onto or in the depth of ECM layer and/or (ii) printing bioinks containing both cells and ECM-like printable biomaterial. The aim of this article was to evaluate combinatorial effects of laser pulse energy, ECM thickness and viscosity of the bioink on cell viability. A LAB workstation was used to print Ea.hy926 endothelial cells onto a quartz substrate covered with a film of ECM mimicking Matrigel™. Hence, effect of laser energy, Matrigel™ film thickness and bioink viscosity was addressed for different experimental conditions (8-24 μJ, 20-100 μm and 40-110 mPa s, respectively). Cell viability was assessed by live/dead assay performed 24 h post-printing. Results show that increasing the laser energy tends to augment the cell mortality while increasing the thickness of the Matrigel™ film and the viscosity of the bioink support cell viability. Hence, critical printing parameters influencing high cell viability have been related to the cell landing conditions and more specifically to the intensity of the cell impacts occurring at the air-ECM interface and at the ECM-glass interface. 相似文献
88.
以华山松种子为研究材料,通过研究不同质量分数(0.2%、0.5%)四唑溶液、不同染色温度和不同染色时间对华山松 种子生活力的影响,探索出测定华山松种子生活力的最佳条件。 通过萌发率对比,得出:在 30 ℃下用质量分数为 0.5%的四唑 溶液染色为最佳染色条件,且染色时间仅需要 5 h;胚全部染色,胚乳未染色面积小于 1 / 3 的种子具有生活力。 相似文献
89.
钟华 《暨南大学学报(自然科学与医学版)》2004,25(2):205-209
心脏心肌功能的判断对疾病的治疗和预后极为重要。心肌存活属于可逆性心肌损害,故冠状动脉血运重建术可获益。存活心肌的检测,区分可逆性和不可逆性心肌损害,具有决策价值和预后价值。通过回顾近年来单光子心肌断层显像(SPECT)评价心肌存活的各种方法以及对比研究,以综合阐述SPECT对心肌存活评价的价值和最新进展,并对SPECT的未来作一初步探讨。 相似文献
90.