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991.
Brandon S. Nichols Erika Chelales Roujia Wang Amanda Schulman Jennifer Gallagher Rachel A. Greenup Joseph Geradts Josephine Harter Paul K. Marcom Lee G. Wilke Nirmala Ramanujam 《Journal of biophotonics》2020,13(10)
Use of genomic assays to determine distant recurrence risk in patients with early stage breast cancer has expanded and is now included in the American Joint Committee on Cancer staging manual. Algorithmic alternatives using standard clinical and pathology information may provide equivalent benefit in settings where genomic tests, such as OncotypeDx, are unavailable. We developed an artificial neural network (ANN) model to nonlinearly estimate risk of distant cancer recurrence. In addition to clinical and pathological variables, we enhanced our model using intraoperatively determined global mammographic breast density (MBD) and local breast density (LBD). LBD was measured with optical spectral imaging capable of sensing regional concentrations of tissue constituents. A cohort of 56 ER+ patients with an OncotypeDx score was evaluated. We demonstrated that combining MBD/LBD measurements with clinical and pathological variables improves distant recurrence risk prediction accuracy, with high correlation ( r = 0.98) to the OncotypeDx recurrence score. 相似文献
992.
993.
994.
A new method has been used to determine what fraction of human erythrocyte cholesterol is available for exchange with plasma unesterified cholesterol. Erythrocytes labeled with 3H-cholesterol by this exchange process were incubated with sonicated phosphatidylcholine vesicles, giving rise to a net movement of cholesterol out of the cells. The specific activity of cholesterol taken up by the vesicles depended on the length of time of incubation. Initially the specific activity in the vesicles was greater than that in the cells, but after approximately 10% of cell cholesterol had been removed, the specific activity of subsequently removed cholesterol was equal to that of the remaining erythrocyte cholesterol. We conclude from these data that (a) all of the cholesterol in the erythrocyte is exchangeable with plasma, and (b) approximately 10% of erythrocyte cholesterol is in a more rapidly exchangeable pool than the remainder. 相似文献
995.
The House mice (Mus musculus L.) of the Faroe Islands (62°N, 7°W) are frequently quoted as examples of rapid evolution, because they seem to be clearly differentiated both from mice in other parts of the world, and between different islands within the Faroe group despite being introduced through human agency within the last millennium. They are also of interest in being among the most climatically stressed mice in the Northern Hemisphere.
The present study is an attempt to determine the extent of differentiation between the populations on the six Faroe islands which harbour mice. It is based on size and organ weights, measurements on the mandibles and scapulae, non-metrical variation of the skeleton, and allozymic frequencies at 22 loci. Distance statistics calculated for all five groups of data between samples from each island compared with every other, showed that all the populations were clearly distinct. However the distances calculated from the different data were disconcertingly heterogeneous. The most likely explanation is that the different characteristics scored each depend on a relatively small number of different genes.
Taking all the results together, it seems most probable that mice first entered the Faroes via the main port of Torshavn and spread from there to Nols0y, Hestur and Sand0y, and from Sand0y to Fugloy and Mykines. The large inter-island differences can be attributed primarily to "instant sub-speciation" produced by each colonization depending on a probable small number of effective founders. 相似文献
The present study is an attempt to determine the extent of differentiation between the populations on the six Faroe islands which harbour mice. It is based on size and organ weights, measurements on the mandibles and scapulae, non-metrical variation of the skeleton, and allozymic frequencies at 22 loci. Distance statistics calculated for all five groups of data between samples from each island compared with every other, showed that all the populations were clearly distinct. However the distances calculated from the different data were disconcertingly heterogeneous. The most likely explanation is that the different characteristics scored each depend on a relatively small number of different genes.
Taking all the results together, it seems most probable that mice first entered the Faroes via the main port of Torshavn and spread from there to Nols0y, Hestur and Sand0y, and from Sand0y to Fugloy and Mykines. The large inter-island differences can be attributed primarily to "instant sub-speciation" produced by each colonization depending on a probable small number of effective founders. 相似文献
996.
Takao Tsuji Josephine Encarciaon Joya Takeshi Honda Toshio Miwatani 《FEMS microbiology letters》1990,67(3):329-332
We have previously reported that the heat-labile enterotoxin (LTc) isolated from a chicken enterotoxigenic Escherichia coli (ETEC) was identical to LTh produced by human ETEC (Tsuji et al. (1988) FEMS Microbiol Lett. 52, 79-84). In this study, we purified an LTc-like toxin (LTc') from another strain isolated from a chicken that developed diarrhea at a different place and time to the previously reported chicken. Its molecular weight and antigenicity were compared with those of purified LTs from porcine and human ETEC (LTp and LTh). The A subunit of LTc' was identical to those of the purified LTs in mobility on SDS-polyacrylamide gel electrophoresis. The Ouchterlony test demonstrated that LTc' was antigenically identical to LTp. The isoelectric point and amino acid composition of LTc' were also identical to those of LTp. These data suggest that chicken ETEC can be grouped with both the porcine and human types on the basis of the LTs produced. 相似文献
997.
Noriko Akashi Shunji Hitotsubashi Hiroyasu Yamanaka Yoshio Fujii Takao Tsuji Akio Miyama Josephine Encarnacion Joya Keinosuke Okamoto 《FEMS microbiology letters》1993,109(2-3):311-315
Abstract Enterotoxigenic Escherichia coli isolated from diarrhea stools of chickens were examined for production of heat-stable enterotoxin II which is considered to be implicated only in diarrhea of pigs. Seven out of 38 strains examined were found to contain heat-stable enterotoxin II gene, determined by colony hybridization and the polymerase chain reaction. The culture supernatants of these strains caused fluid accumulation in the mouse intestinal loop test. This fluid accumulation activity was not lost by heating at 100°C and was neutralized by anti-heat-stable enterotoxin II antiserum. Purified heat-stable enterotoxin II caused fluid accumulation in the chicken intestinal loop assay. These results indicate that STII-producing E. coli is implicated in chicken diarrhea. 相似文献
998.
Josephine Cardale 《Australian Journal of Entomology》1968,7(1):35-41
i
Immature stages of two species in each of the two tribes, Anthophorini and Melectini, of Anthophorinae found in Australia were studied for the first time. The larvae and pupa of Amegilla (Amegilla) pulchra (Smith), the mature larva and pupa of Amegilla (Asarapoda) sp., the mature larva of Thyreus lugubris (Smith) and the pupa of Thyreus caeruleopunctatus (Blanchard) are described and the larvae are figured, and information is given on their behaviour and development. 相似文献
Immature stages of two species in each of the two tribes, Anthophorini and Melectini, of Anthophorinae found in Australia were studied for the first time. The larvae and pupa of Amegilla (Amegilla) pulchra (Smith), the mature larva and pupa of Amegilla (Asarapoda) sp., the mature larva of Thyreus lugubris (Smith) and the pupa of Thyreus caeruleopunctatus (Blanchard) are described and the larvae are figured, and information is given on their behaviour and development. 相似文献
999.
HISTONE F1 OF TETRAHYMENA MACRONUCLEI : Unique Electrophoretic Properties and Phosphorylation of F1 in an Amitotic Nucleus 总被引:4,自引:2,他引:2 下载免费PDF全文
Martin A. Gorovsky Josephine Bowen Keevert Gloria Lorick Pleger 《The Journal of cell biology》1974,61(1):134-145
Histone fraction F1 has been isolated and purified from macronuclei of the ciliated protozoan, Tetrahymena pyriformis. In many respects, Tetrahymena F1 is similar to that of other organisms. It is the only Tetrahymena histone soluble in 5% perchloric acid or 5% trichloroacetic acid, has a higher molecular weight than any other Tetrahymena histone, is the histone most easily dissociated from Tetrahymena chromatin, and is susceptible to specific proteolytic cleavage. However, unlike F1 in all other organisms, Tetrahymena F1 is not the slowest-migrating histone fraction when analyzed by polyacrylamide gel electrophoresis at low pH. Tetrahymena F1 also exhibits unusual behavior in sodium dodecyl sulfate-containing polyacrylamide gels, migrating faster than calf thymus F1 at pH 10, and slower than calf thymus F1 at pH 7.6. Tetrahymena F1 was found to be highly phosphorylated in rapidly growing cells, suggesting that the relationship between cell replication and F1 phosphorylation previously observed in mammalian cells may extend to all eukaryotes. The observation that extensive F1 phosphorylation occurs in macronuclei, which divide amitotically, argues against a unique role for F1 phosphorylation in the process of chromosome condensation at mitosis. 相似文献
1000.
A numerical taxonomic study of non-motile non-fermentative Gram-negative bacteria from foods 总被引:4,自引:4,他引:0
A numerical taxonomic study using 155 unit characters was performed on 63 strains of Gram-negative non-motile non-fermentative bacteria isolated from proteinaceous foods. Similar bacteria from other sources and several Pseudomonas strains from meat were included for reference purposes. Three clusters were observed at 76% S which contained all the food strains. Cluster 1 was composed entirely of Acinetobacter strains including 17 isolated from foods that were provisionally identified with Acinetobacter johnsonii. Cluster 2 contained 22 strains identified as Psychrobacter immobilis , of which 20 were from food. Cluster 3 contained all the Pseudomonas reference strains and 26 non-motile strains isolated from meat. These were shown to be non-motile variants of Pseudomonas fragi. A simple identification scheme, based on five tests, is presented for the distinction of the three types of bacteria. 相似文献