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251.
Effects of juglone on seedling growth of cucumber (Cucumis sativus cv. Beith Alpha) with respect to physiological and anatomical parameters were investigated. Growth parameters (seedling elongation, fresh and dry weights) were reduced by 1 mM juglone. Juglone also decreased chlorophyll a and b contents and reduced some anatomical tissues (xylem vessel and bundle radius of stem, stomata length and stomata number of the cotyledons). The anatomical changes in stem and cotyledon of the seedlings were related to growth inhibiting effect of juglone. On the other hand, increase in catecholase and tyrosinase activities by the effect of juglone were also recorded.  相似文献   
252.
Aim:  The aim of this study was to demonstrate the occurrence of potential pathogenic Vibrio parahaemolyticus in seafoods using DNA-based techniques in comparison with bacteriological methods.
Methods and Results:  From 120 fresh and processed fish and mussel samples collected from Middle Black Sea, 32 isolates were identified as V. parahaemolyticus by bacteriological methods and confirmed by tl gene-based conventional PCR. Of them, 13 isolates were found positive for only tdh gene, six isolates for only trh gene and 13 isolates for both genes by multiplex PCR.
Conclusions:  It is the first report demonstrating the presence of potential pathogenic V. parahaemolyticus isolates from the Black Sea seafoods by PCR detection of tl , trh and tdh genes that was found more rapid than bacteriological methods.
Significance and Impact of the Study:  This study confirmed the previous reports that characterization of potential pathogenic V. parahaemolyticus isolates based on the PCR techniques was reliable and cost-effective. These results suggest that molecular detection methods should be included in Turkish Standards of seafood control in addition to bacteriological methods.  相似文献   
253.
E Terzi  L Poteur  E Trifilieff 《FEBS letters》1992,309(3):413-416
Phospholamban (PLB), an integral membrane protein of cardiac sarcoplasmic reticulum (SR), is described as the regulator of the Ca(2+)-ATPase pump, via its phosphorylation-dephosphorylation of Ser-16. Recently it has been shown that a direct interaction between the N-terminal hydrophilic domain of PLB and Ca(2+)-ATPase may be one of the mechanisms of regulation. In order to show that this interaction could be modulated by a phosphorylation-induced conformational change in PLB, we ran CD studies on the synthetic peptide PLB(2-33) in its phosphorylated and non-phosphorylated forms, at various pHs, concentrations and in the absence or presence of trifluoroethanol. The results show a clear difference in structure of the phosphorylated and non-phosphorylated peptide.  相似文献   
254.
Effects of lambda-phage infection on bacterial synthesis   总被引:5,自引:0,他引:5  
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255.
Physiology of bacteriophage lambda in the restrictive host   总被引:3,自引:0,他引:3  
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256.
This study aimed to parameterize the effects of body and meal sizes on the gastric evacuation (GE) of farmed Russian sturgeon (Acipenser gueldenstaedtii) fed on live food (whiting fish) or commercial pellets. The radiography technique was used to monitor the evacuation of food from the stomach into the intestine at postprandial time. Acipenser gueldenstaedtii of different body sizes (total length ranged 82–105 cm) were fed on meal sizes ranged from 23 to 72 g composed of either live food or commercial pellets (had a 20% of BaSO4 as a radiopaque material). The square root model was found to adequality describe the process of GE in A. gueldenstaedtii independently of meal type and size. The effects of fish size on GER was described by simple power model and can be summarized by , where ρL was 0.000053 for live food and 0.000062 for commercial pellets (estimated from combined GE data), St is stomach contents (g), L is fish total length (cm) and t is time (h). The results of this study will provide a useful tool to estimate the stomach fullness of A. gueldenstaedtii at postprandial time t. Such information should assess the feeding strategy to minimize feed wastage and optimize the fish growth.  相似文献   
257.
Methionine-enkephalin first inhibited and then stimulated the spontaneous rhythmic activity of the rabbit isolated ileum. The inhibitory effect of methionine-enkephalin was antagonized by naloxone. On the contrary, atropine did not change significantly either the inhibitory or the stimulatory action of this peptide. Furthermore, methionine-enkephalin inhibited the peristaltic reflex of the rabbit isolated ileum as well. Naloxone completely antagonized the inhibition of peristalsis produced by methionine-enkephalin. On the other hand, acetylcholine reversed only the propulsive activity and the back pressure, but not the peristaltic movements of the longitudinal muscle previously abolished by methionine-enkephalin. It appears, therefore, that only the inhibitory effects of methionine-enkephalin are mediated through opioid receptors in the intestine.  相似文献   
258.
The authors study the statistical distribution and the graphical representation of the urinary chromium values investigated during three consecutive years in three work environments of a same plant: polishing 1 degree, electrotyping, polishing 2 degrees, to evaluate the environmental situations of exposure and their variations. The adopted method, based on the graphical representation of the values in logarithmic coordinate paper, allows to quickly and carefully calculate the percent of the workers having urinary chromium values above the prefixed limits.  相似文献   
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