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41.
Genetic data suggesting the absence of crossover in Saccharomycodes ludwigii have been described. Tetrad data obtained from 888 asci from 60 pairs of genes with 22 genetic markers showed the absence of tetratype asci, except for 5 asci in which a single pair of alleles showed tetratype segregation to the other genetic markers in each ascus. Spore arrays in the linear asci showed that the + - + - and + - - + (or - + + -) asci occurred at almost equal frequencies. The two coherent spores at each end of an ascus were always marked with different alleles of a gene.  相似文献   
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Patients with hormone receptor(HR)-positive tumors breast cancer usually experience a relatively low pathological complete response(p CR) to neoadjuvant chemotherapy(NAC). Here, we derived a 10-micro RNA risk score(10-mi RNA RS)-based model with better performance in the prediction of p CR and validated its relation with the disease-free survival(DFS) in 755 HRpositive breast cancer patients(273, 265, and 217 in the training, internal, and external validation sets, respectively). This model,pres...  相似文献   
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A sensitive method for determination of sialic acids by monitoring the fluorescence produced with malononitrile in borate buffer has been established. Measurement of the fluorescence intensity of the reaction mixture at 430 nm with irradiation at 360 nm allowed determination of 3-60 nmol of sialic acids with high reproducibility. A few amino sugars and deoxy sugars, as well as catecholamines reacted with this reagent; however other carbohydrates, amino acids, amines, aldehydes, and carboxylic acids including alpha-keto acids, etc., showed little reactivity. This method was successfully applied to postcolumn fluorescence labeling of sialic acids in high-performance liquid chromatography.  相似文献   
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SGIP1 has been shown to be an endophilin-interacting protein that regulates energy balance, but its function is not fully understood. Here, we identified its splicing variant of SGIP1 and named it SGIP1alpha. SGIP1alpha bound to phosphatidylserine and phosphoinositides and deformed the plasma membrane and liposomes into narrow tubules, suggesting the involvement in vesicle formation during endocytosis. SGIP1alpha furthermore bound to Eps15, an important adaptor protein of clathrin-mediated endocytic machinery. SGIP1alpha was colocalized with Eps15 and the AP-2 complex. Upon epidermal growth factor (EGF) stimulation, SGIP1alpha was colocalized with EGF at the plasma membrane, indicating the localization of SGIP1alpha at clathrin-coated pits/vesicles. SGIP1alpha overexpression reduced transferrin and EGF endocytosis. SGIP1alpha knockdown reduced transferrin endocytosis but not EGF endocytosis; this difference may be due to the presence of redundant pathways in EGF endocytosis. These results suggest that SGIP1alpha plays an essential role in clathrin-mediated endocytosis by interacting with phospholipids and Eps15.  相似文献   
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Nitrogen and carbon components in domestic modified wastewater were completely removed by simultaneous nitrification and denitrification using a membrane-aerated biofilm reactor where biofilm was fixed on a hollow-fiber membrane. To measure the spatial distribution of pH, ammonium and nitrate ions and to observe microbes inside the biofilm fixed on the membrane, microelectrodes and the fluorescence in situ hybridization (FISH) method were applied. Due to plug flow in the vertical direction (from the bottom to the top of the reactor), ammonium nitrogen was gradually removed and negligible nitrate nitrogen was detected throughout the reactor. FISH revealed that ammonia-oxidizing bacteria were mainly distributed inside the biofilm and other bacteria, which included denitrifying bacteria, were mainly distributed outside the biofilm and over the suspended sludge. In order to characterize bacterial activity in the vertical direction of the reactor, nitrification rates at lower, central and upper points were calculated using microelectrode data. The nitrification rate at the lower point was 7 and 125 times higher than those at the central and upper points, respectively. These results show that the removal of carbon and nitrogen compounds was accomplished efficiently by using various kinds of bacteria distributed vertically and horizontally in a single reactor.  相似文献   
47.
Although diabetic nephropathy (DN) is a major cause of end-stage renal disease, the mechanism of dysfunction has not yet been clarified. We previously reported that in diabetes proinsulin-producing bone marrow-derived cells (BMDCs) fuse with hepatocytes and neurons. Fusion cells are polyploidy and produce tumor necrosis factor (TNF)-α, ultimately causing diabetic complications. In this study, we assessed whether the same mechanism is involved in DN. We performed bone marrow transplantation from male GFP-Tg mice to female C57BL/6J mice and produced diabetes by streptozotocin (STZ) or a high-fat diet. In diabetic kidneys, massive infiltration of BMDCs and tubulointerstitial injury were prominent. BMDCs and damaged tubular epithelial cells were positively stained with proinsulin and TNF-α. Cell fusion between BMDCs and renal tubules was confirmed by the presence of Y chromosome. Of tubular epithelial cells, 15.4% contain Y chromosomes in STZ-diabetic mice, 8.6% in HFD-diabetic mice, but only 1.5% in nondiabetic mice. Fusion cells primarily expressed TNF-α and caspase-3 in diabetic kidney. These in vivo findings were confirmed by in vitro coculture experiments between isolated renal tubular cells and BMDCs. It was concluded that cell fusion between BMDCs and renal tubular epithelial cells plays a crucial role in DN.  相似文献   
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N-Methyl-d-aspartate (NMDA) receptors have been implicated in learning and memory, and may also play a central role in various conditions leading to neuronal degradation. NMDA receptor antagonists could therefore be of therapeutic benefit for a number of neurological disorders. We have designed hybrid compounds of polyamines and memantine, both of which function as NMDA channel blockers. The triamine derivative with a guanidine moiety showed more potent antagonistic activity than memantine.  相似文献   
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