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61.
Archives of Gynecology and Obstetrics - To examine trends, characteristics and outcomes of women who develop both ovarian and breast cancers. This is a retrospective study examining the...  相似文献   
62.
Lineage switch is a rare event at leukemic relapse. While mostly known to occur in KMT2A‐rearranged infant leukemia, the underlying mechanism is yet to be depicted. This case report describes a female infant who achieved remission of KMT2AMLLT3‐rearranged acute monocytic leukemia, but 6 months thereafter, relapsed as KMT2AMLLT3‐rearranged acute lymphocytic leukemia. Whole exome sequencing of the bone marrow obtained pre‐post lineage switch revealed two somatic mutations of PAX5 in the relapse sample. These two PAX5 alterations were suggested to be loss of function, thus to have played the driver role in the lineage switch from acute monocytic leukemia to acute lymphocytic leukemia.  相似文献   
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64.
The aim of this study was to evaluate whether transplantation of Schwann cells derived from bone marrow stromal cells (BMSC-SCs) promotes axonal regeneration and functional recovery in completely transected spinal cord in adult rats. Bone marrow stromal cells (BMSCs) were induced to differentiate into Schwann cells in vitro. A 4-mm segment of rat spinal cord was removed completely at the T7 level. An ultra-filtration membrane tube, filled with a mixture of Matrigel (MG) and BMSC-SCs (BMSC-SC group) or Matrigel alone (MG group), was grafted into the gap. In the BMSC-SC group, the number of neurofilament- and tyrosine hydroxylase-immunoreactive nerve fibers was significantly higher compared to the MG group, although 5-hydroxytryptamine- or calcitonin gene-related peptide-immunoreactive fibers were rarely detectable in both groups. In the BMSC-SC group, significant recovery of the hindlimb function was recognized, which was abolished by retransection of the graft 6 weeks after transplantation. These results demonstrate that transplantation of BMSC-SCs promotes axonal regeneration of lesioned spinal cord, resulting in recovery of hindlimb function in rats. Transplantation of BMSC-SCs is a potentially useful treatment for spinal cord injury.  相似文献   
65.
Genetic analyses of highly pathogenic avian influenza H5 subtype viruses isolated from the Izumi Plain, Japan, revealed cocirculation of 2 genetic groups of clade 2.3.4.4b viruses among migratory waterfowl. Our findings demonstrate that both continuous surveillance and timely information sharing of avian influenza viruses are valuable for rapid risk assessment.  相似文献   
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67.
The effect of radiotherapy during immunotherapy on immune-related adverse events (irAEs) is not fully understood. We herein report a 74-year-old woman diagnosed with lung adenocarcinoma with programmed death ligand 1 expression ≥50% and treated with pembrolizumab. She developed fatal immune thrombocytopenia associated with pembrolizumab immediately following radiotherapy. A flow cytometry analysis of peripheral blood detected an increased expression of programmed death-1 (PD-1) and Ki-67 in CD4 and CD8 T cells after radiotherapy, compared with pre-irradiation measurements. This case suggests that radiotherapy may evoke irAEs during treatment with anti-PD-1 antibodies, which physicians should consider when using radiotherapy in patients treated with these drugs.  相似文献   
68.
Purpose. The aim of the present work was to develop a new in vitro system to evaluate oral absorption of poorly water-soluble drugs by utilizing Caco-2 monolayers. Methods. Caco-2 monolayer was mounted between side-by-side chambers, which enabled the simultaneous assay of dissolution and permeation of drugs (dissolution/permeation system; D/P system). Apical and basal sides of the chamber were filled with buffer solutions. Drugs were applied to the apical side as powder, suspension, or solution, and then, the permeated amounts into the basal side were monitored for 2 h. At the same time, dissolved amounts of drugs at the apical side were detected. The amount of drug applied to the D/P system was based on its in vivo clinical dose. Results. Sodium taurocholate (5 mM, apical side) and bovine serum albumin (4.5% w/v, basal side) increased the permeated amount of poorly water-soluble drugs. Both additives were considered to be effective at mimicking in vivo conditions of intestinal drug absorption. From the correlation between the permeated amount of 13 drugs (% dose/2 h) in the D/P system and their percentage dose absorbed in humans in vivo, this system was found to be useful in evaluating oral absorption of poorly water-soluble drugs. Conclusions. With attempts made to mimic the physiologic conditions of the human GI tract, in vivo oral absorption of drugs was quantitatively assessed in the D/P system in vitro. This system is quite useful to predict the oral absorption of poorly water-soluble drugs after administration as solid dosage forms.  相似文献   
69.
The non-ionic detergent Tween 80, which is used as a solvent for lipophilic drugs such as VP-16 and Taxotere, was found to reverse VP-16 resistance of the P-glycoprotein-associated multidrug resistance phenotype via increasing VP-16 influx. In adriamycin-resistant human chronic myelogenous leukemia K562 cells (K562/ADM), which overexpress mdr1 mRNA, the accumulation of VP-16 was only about 10% that in wild-type K562 cells. Tween 80 enhanced VP-16 accumulation in K562/ADM cells but did not influence VP-16 accumulation in parental K562 cells. VP-16 efflux was rapid and similar in both sensitive and resistant cell lines and was not blocked by Tween 80 or verapamil. Under glucose-free conditions, VP-16 accumulation in K562/ADM cells was only half of that in K562 cells. Tween 80 increased VP-16 accumulation in K562/ADM cells in glucose-free medium. In growth inhibition assay, Tween 80 reversed K562/ADM sensitivity to VP-16 without cell damage. Taken together, Tween 80 reverses VP-16 sensitivity in multidrug-resistant K562 cells by increasing influx, which is considered to be the primary mechanism of VP-16 resistance in K562/ADM cells.  相似文献   
70.
In this study, we compared the kinetics of the postirradiation p53 protein expression for carbon ion beam (290 MeV/n, LET 75 keV/mu m) and proton beam (65 MeV) with that of (13)7Cs-gamma ray. We used two human lymphoblastoid cell lines derived from the same donor with different p53 status. Wild-type p53 protein increased after irradiation and it was dose-dependent. Meanwhile, the mutated p53 protein level did not show any increase with irradiation. With the three forms of radiation, there was no significant difference as regards the p53 protein kinetics.  相似文献   
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