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361.
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The applicability of a bacterial storage method (maintenance after absorption on cryopreservative-immersed ceramic beads) was tested for different fungal strains of biotechnological importance: Aspergillus, Mucor, Phaffia, Rhizomucor and Saccharomyces. Polyethylene glycol (100ml of 30% or 45% solutions) added after the transfer of cells into the vial increased the safety of storage.  相似文献   
363.
Journal of Insect Conservation - The presence of Palingenia longicauda was considered to be restricted to the Tisza River basin (sub-basin of the Danube River Basin) and the Rába River...  相似文献   
364.
A new method for growing isolated wheat zygotes by co-cultivation with microspores isolated from the same species has been developed. Although the mortality of isolated zygotes within 6 h after the transfer into the nurse culture was relatively high (70%) in this method, the majority of the structures which survived developed into fertile plants (61%). Zygotic structures grown in these cultures were morphologically not as regular as embryos grown in planta, but they resembled them closely in cytological properties and developmental pattern.  相似文献   
365.
This paper focuses on enzymatic esterifications in non-conventional media (organic solvents, ionic liquids, and solvent-free systems) with reference to the water removal. Different types of water removal techniques are reviewed with a special emphasis on pervaporation. Pervaporation is a separation process in which liquid is transported through a selective membrane with simultaneous evaporation of permeates. In an integrated process where pervaporation is coupled with a bioreactor where esterification is performed, selective removal of water or other esterification products can be achieved. In this manner benefit can be doubled, due to the equilibrium shift and possible pure product recovery. Available literature on esterifications coupled with pervaporation is presented in detail. Reviewed examples are divided according to the type of reaction media.  相似文献   
366.
Metabolomics - The 2,6-dichloro-1,4-benzoquinone (DCBQ) and its derivative 2,6-dichloro-3-hydroxy-1,4-benzoquinone (DCBQ-OH) are disinfection by-products (DBPs) and emerging pollutants in the...  相似文献   
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It has been established that in sodium isethionate Ringer's solution containing chloride ions at low concentration (0-6.1 mmol/l) a repetitive firing of action potentials (APs) could be induced systematically by stimulation of muscle fibres with single square impulses. Repetitive firings occurred also on slow depolarization elicited by different agents e.g. by some antibiotics (primycin, desertomycin) which block potassium channels, or aldehydes (acrolein). On the basis of own and literary data it is concluded that under physiological conditions a high chloride concentration in the extracellular space prevents the occurrence of repetitive firing of APs which would result from the depolarization of tubular membrane on potassium ion accumulation in the luminal fluid of T-tubules.  相似文献   
370.
The anti-senescence effect of low-concentrations of some stress-inducing compounds of different toxicity and chemical nature such as Cd and Pb salts or 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) was investigated in the primary leaves of bean seedlings. In these leaves treated by spraying, chlorophyll content and photosynthetic activity increased, the active cytokinin content of roots and leaves was also significantly higher as compared to the control. These symptoms of stimulation could be eliminated by the inhibitors Li and PD [2-(2′-amino-3′-methoxyphenyl)-oxanaphthalen-4-one] added to each agent, indicating the involvement of PIP2-IP3/DAG and MAPK signaling pathways, respectively, in the response.  相似文献   
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