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1.
A simple apparatus was developed to allow 12 petri plates to be poured simultaneously by hand. It was used when screening
bacterial isolates from sewage and dog feces for their ability to detect phages from these sources. This was done to assess
the ease with which source-specific phage hosts can be isolated from these sources of fecal pollution. Host bacteria that
consistently detected phages from sewage were easily isolated from sewage. These bacterial isolates did not detect phages
from dog feces. Host bacteria were not isolated from dog feces even after screening hundreds of colonies from fecal samples
from six dogs. Journal of Industrial Microbiology & Biotechnology (2000) 24, 124–126.
Received 06 July 1999/ Accepted in revised form 05 November 1999 相似文献
2.
S G Lee G A Ricca G Crumley R S Lloyd W Drohan 《Biochemical and biophysical research communications》1988,151(1):598-607
Plasmids expressing 2 forms of human immune interferon (IFN-gamma) in E. coli have been constructed: 1) pIFNTacI which expresses IFN-gamma with an N-terminal amino acid sequence of met-cys-tyr-cys-gln-, and 2) pIFNTacII which is a derivative of pIFNTacI from which the 9 base pairs (bp) coding for the cys-tyr-cys have been deleted. Quantitation of Western blots showed that approximately 10-fold more IFN-gamma was produced in cells harboring pIFNTacII (7.5% of total cellular protein) as compared to pIFNTacI. The IFN-gamma expressed in E. coli pIFNTacII is biologically active and routinely recoverable at 10(9) units per liter. When examined microscopically, IPTG induced E. coli harboring either plasmid construction contains prominent cytoplasmic inclusion bodies. 相似文献
3.
R Raffaele B Anicito A Battiato E Cosentino A Palmeri G Ricca A Casabona V Perciavalle 《Bollettino della Società italiana di biologia sperimentale》1990,66(9):873-877
With the aim of evaluating the excitability of the brain stem reflex centers, we studied the side-to-side differences in the EMG activity of the early and late components of the blink reflex, in subjects with unilateral dystonia without demonstrable brain lesions. We observed that both early and late responses of direct blink reflex were significantly higher in the affected side than in the contralateral one. 相似文献
4.
Margherita Sacco Ezio Ricca Rosangela Marasco Roberta Paradiso Maurilio De Felice 《FEMS microbiology letters》1993,107(2-3):331-336
5.
The venom glands of Heteropneustes lie deep in the epidermis at the sides of the pectoral fin spines, and consist of large cells that react positively to histochemical tests for proteins, histidine and tyrosine, negatively to periodic acid-Schiff and for serotonin and bombesin. The venom cells are of two types, appearing to have dense or lucent cytoplasm when seen by electron microscopy. The dense type has the better developed Golgi systems, the lucent type has more ribosomes. Both appear to differentiate from the basal layer of the epidermis. The epidermis over the glands has a zone with relatively few desmosomes and enlarged intercellular spaces. Both staining reactions and fine structure differentiate the venom gland cells from the club cells of the epidermis, to such an extent that they must be considered distinct secretory elements. 相似文献
6.
G. Zaccone G. Tagliafierro S. Fasulo A. Contini L. Ainis M. B. Ricca 《Histochemistry and cell biology》1990,93(4):355-357
Summary The present immunocytochemical study concerns the distribution of serotonin in the epidermis of three species of teleost fish. Serotonin-like immunoreactivity was found in the club cells of Heteropneustes fossilis and Carapus acus but not in those from the sea eel Conger conger. This study is the first immunocytochemical identification of serotonin in the club cells of teleost epidermis. By comparing data from the literature (Zaccone et al. 1986, 1987, 1988) regarding the occurrence of serotonin and GRP/bombesin in the exocrine sacciform gland cells of piscine skin, it is worthy mentioning here that the serotonin contained in the club cells of the species studied may have the ability to affect the pheromonal or other possible functions of these cells. The presence of serotonin in these systems has been correlated with the capacity of the exocrine glands of fish skin to secrete, ectopically, amine messengers in contrast to those produced eutopically i.e. in the neuron-paraneuron system in some vertebrates (Fujita et al. 1988). 相似文献
7.
8.
Lindorff-Larsen K Paci E Serrano L Dobson CM Vendruscolo M 《Biophysical journal》2003,85(2):1207-1214
Recent advances in experimental and computational methods have made it possible to determine with considerable accuracy the structures whose formation is rate limiting for the folding of some small proteins-the transition state ensemble, or TSE. We present a method to analyze and validate all-atom models of such structures. The method is based on the comparison of experimental data with the computation of the change in free energy of the TSE resulting from specific mutations. Each mutation is modeled individually in all members of an ensemble of transition state structures using a method originally developed to predict mutational changes in the stability of native proteins. We first apply this method to six proteins for which we have determined the TSEs with a technique that uses experimental mutational data (Phi-values) as restraints in the structure determination and find a highly significant correlation between the calculated free energy changes and those derived from experimental kinetic data. We then use the procedure to analyze transition state structures determined by molecular dynamics simulations of unfolding, again finding a high correlation. Finally, we use the method to estimate changes in folding rates of several hydrophobic core mutants of Fyn SH3. Taken together, these results show that the procedure developed here is a tool of general validity for analyzing, assessing, and improving the quality of the structures of transition states for protein folding. 相似文献
9.
Sadiq I Fanucchi F Paparelli E Alpi E Bachi A Alpi A Perata P 《Journal of plant physiology》2011,168(18):2234-2243
Rice is the staple food for more than fifty percent of the world's population, and is therefore an important crop. However, its production is hindered by several biotic and abiotic stresses. Although rice is the only crop that can germinate even in the complete absence of oxygen (i.e. anoxia), flooding (low oxygen) is one of the major causes of reduced rice production. Rice germination under anoxia is characterized by the elongation of the coleoptile, but leaf growth is hampered. In this work, a comparative proteomic approach was used to detect and identify differentially expressed proteins in the anoxic rice coleoptile compared to the aerobic coleoptile. Thirty-one spots were successfully identified by MALDI-TOF MS analysis. The majority of the identified proteins were related to stress responses and redox metabolism. The expression levels of twenty-three proteins and their respective mRNAs were analyzed in a time course experiment. 相似文献
10.
Emanuela Foglia Paolo Bonfanti Giuliano Rizzardini Erminio Bonizzoni Umberto Restelli Elena Ricci Emanuele Porazzi Francesca Scolari Davide Croce 《PloS one》2013,8(2)