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961.
P Salgame A S Varadhachary L L Primiano J E Fincke S Muller M Monestier 《Nucleic acids research》1997,25(3):680-681
We describe a simple and convenient enzyme-linked immunosorbent assay (ELISA) for the detection of apoptosis in tissue culture. An early event in apoptosis is DNA fragmentation followed by release of nucleosomes into the cytoplasm. Our sandwich assay uses a pair of monoclonal antibodies specific for two nucleosomal epitopes to capture and detect cytoplasmic nucleosomes onto the ELISA plate. Our assay is about 500 times more sensitive than the detection of apoptotic DNA ladder by agarose electrophoresis and is especially suited for the testing of large numbers of samples. 相似文献
962.
The optimum temperature for multiplication of legionella strains in culture media is around 37°C. The effect of high temperatures on the growth of strains isolated from various environments is poorly known. We studied the growth (cell multiplication, respiration) of clinical and environmental Legionella pneumophila strains in liquid media at intervals of 0.5°C in the temperature range from 41.6 to 51.6°C using a temperature gradient incubator. Cell multiplication and CO2 production decreased markedly with all the strains at temperatures above 44–45°C. CO2 continued to be produced up to 51.6C even if cell multiplication generally stopped at around 48.4–50.0C. Thus, legionella retained its metabolic activity beyond the maximum temperature for cell multiplication. The CO2 production per bacterial cell (metabolic quotient, qCO2 ) increased with increasing temperature up to 45°C, whereafter it decreased, the turning point being almost at the same at which the rate of cell multiplication decreased. The difference in qCO2 between the strains may reflect their different physiological capacities for tolerating high temperatures. 相似文献
963.
J. M. SORIANO S. PECCHIOLI C. ROMERO S. VILANOVA G. LLCER E. GIORDANI M. L. BADENES 《Molecular ecology resources》2006,6(2):368-370
The oriental persimmon (Diospyros kaki Lf) is believed to have originated in China with subsequent introduction into Japan and Korea in ancient times. The species was then brought to Europe, Brazil and the USA from Japan in the 19th century. Recent studies highlighted the poor state of identification of cultivars in these countries due to incorrect labelling and presence of synonyms among local varieties. Thus, molecular marker characterization of germplasm resources is of great value for genetic resource preservation and plant breeding of persimmon. Therefore, to identify accessions for further plant breeding and germplasm management, 37 microsatellite loci were developed from a CT/AG‐enriched persimmon genomic library. 相似文献
964.
U Pfeffer A Di Vinci E Geido G Vidali W Giaretti 《Journal of cellular physiology》1991,149(3):567-574
We have recently described a novel nuclear antigen, AF-2, which is related to cell cycle dependent alterations of chromatin structure. We show by two parameter flow cytometry on a cell by cell basis that the antigen is accessible to specific monoclonal antibodies only in mitotic and postmitotic early G1-phase cells. The evaluation of nuclease susceptibility and AF-2 antigen accessibility reveals different subcompartments of the G1-phase of the cell cycle with distinct chromatin conformations. Digestion with DNase I seems to alter the chromatin structure according to concentration and this is reflected by an increase of the antigen accessibility. Chromatin in the more condensed early G1-phase is specifically digested by lower concentrations of the enzyme than chromatin in later stages of interphase. Chromatin from cells in the late-G1, S-, and G2-phases shows a higher relative resistance to DNase I and a reduced accessibility of the AF-2 antigen to monoclonal antibodies. Nuclease S1 has a similar effect on chromatin topology, as revealed by the reaction with anti-AF-2 antibodies, without digestion of detectable amounts of DNA. The antigen becomes available to the antibodies in almost all cells by digestion with high concentrations of DNase I or Nuclease S1. 相似文献
965.
E Rudzki Z Grzywa P Rebandel K Parapura 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1988,43(42-43):1374-1376
966.
967.
Chicken gizzard tropomyosin was digested with carboxypeptidase A at the weight ratios of enzyme to substrate 1:200 and 1:50. Removal of about 16 C-terminal amino acid residues per tropomyosin molecule, at lower enzyme concentration, caused reversion of the effect on skeletal actomyosin ATPase activity from activating to inhibiting without an influence on polymerizability and actin-binding ability. Removal of about 26 C-terminal amino acid residues per molecule, at higher enzyme concentration, resulted in loss of polymerizability and actin binding ability. Digestion of gizzard tropomyosin with carboxypeptidase A has no dramatic effect on its binding to troponin T. The results show that not only the existence of head-to-tail overlapping regions but also their length is important for the functional properties of chicken gizzard tropomyosin. 相似文献
968.
E. J. Hyslop 《Journal of fish biology》1987,30(2):183-192
The growth and feeding habits of juvenile Clarias anguillaris (Linné 1762) during their 5-month residence in the floodplain pools of the Sokoto-Rima river basin are described. A mean growth increment of 202 mm and 69.7 g attained in the October to March season compares favourably with first-year growth recorded for other Clarias species. The diet of C. anguillaris is relatively unspecialized and includes a wide variety of items ranging from algae, higher plant material and detritus through larval dipterans, rotifers and copepods, to fish. There is variation in the diet according to month of capture and capture location, and a reduction in diet diversity with fish size. The findings are discussed in the context of work carried out on other Clarias species. It is proposed that C. anguillaris is suitable for locally operated fish culture programmes. 相似文献
969.
The biodegradability potentials of three detergent products with the trade names Omo, Teepol and sodium dodecyl sulfate (SDS)
by the native bacteria of the Lagos lagoon was carried out using the lagoon die-away method. Physicochemical parameters of
the water samples showed that the lagoon in Apapa was more polluted than at theUniversity of Lagos. In 12 days, approximately 30, 60 and 97% of Omo, Teepol and SDS respectively were degraded. SDS with an alkyl sulfate moiety
as surfactant supported the highest growth of the detergent-utilizing organisms, indicating that the components of Omo and
Teepol are more resistant to microbial attack. The detergent-utilizing bacteria identified were mainly Gram-negative and of
the following genera:Vibrio, Klebsiella, Flavobacterium, Pseudomonas, Escherichia, Enterobacter, Proteus, Shigella andCitrobacter. Vibrio was the most frequently encountered organism whileProteus was the rarest. Results of this investigation had shown that detergents made in Nigeria may still contain components that
are recalcitrant to biodegradation. 相似文献
970.