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11.
Biology Bulletin - This study investigated the protective effects of quercetin (QUE) in doxorubicin (DOX)-induced testicular toxicity in rats. In the present study, testicular histomorphometry, the... 相似文献
12.
Young Seung Lee Jae‐Young Chung Sang Bong Jeon Ae‐Kyoung Lee Hyung‐Do Choi 《Bioelectromagnetics》2019,40(7):445-457
This paper proposes a novel in vitro exposure system operating at millimeter‐wave (mmWave) 28 GHz, one of the frequency bands under consideration for fifth generation (5G) communication. We employed the field uniformity concept along cross‐sectional observation planes at shorter distances from the radiation antenna for better efficiency and a small‐size system. A choke‐ring antenna was designed for this purpose in consideration of a wider beamwidth (BW) and a symmetric far‐field pattern across three principal planes. The permittivity of Dulbecco's modified Eagle's medium solution was measured to examine the specific absorption rate (SAR) of the skin cell layer inside a Petri dish model for a three‐dimensional (3D) cell culture in vitro experiment. The best deployment of Petri dishes, taking into account a geometrical field symmetry, was proposed. Local SAR values within the cell layer among the Petri dishes were determined with different polarization angles. It was determined that this polarization effect should be considered when the actual exposure and deployment were conducted. We finally proposed an in vitro exposure system based on the field uniformity including downward exposure from an antenna for 3D cell culture experiments. A small‐size chamber system was obtained, and the size was estimated using the planar near‐field chamber design rule. Bioelectromagnetics. 2019;40:445–457. © 2019 Bioelectromagnetics Society 相似文献
13.
14.
C S Hong Y G Kwak J H Ji S W Chae Do H Kim 《Biochemical and biophysical research communications》2001,289(4):882-887
Junctate is a newly identified integral ER/SR membrane calcium binding protein, which is an alternative splicing form of the same gene generating aspartyl beta-hydroxylase and junctin. Screening a mouse heart cDNA library using canine junctin cDNA as a probe yielded three complete mouse heart cDNAs. One of the cDNAs is homologous to the previously reported human junctate. The three mouse junctate proteins are composed of 270, 259, and 215 amino acids (we named them junctate-1, -2, and -3). The apparent molecular masses of the mouse junctates in SDS-PAGE were in the range between 40 and 53 kDa. Northern and Western blot analyses indicate that mouse junctates are expressed in heart, brain, spleen, lung, liver, kidney, and stomach, but not in skeletal muscle. The apparent molecular weights of junctates from heart and brain were somewhat different from those from the other tissues tested, suggesting that there are tissue-specific expression patterns of the different junctate isoforms. Immunohistochemical studies showed that junctates were expressed both in ventricular and atrial tissues. This is the first study that shows the presence of 3 distinct cardiac junctate isoforms expressed in various mammalian tissues. 相似文献
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16.
Wee1, a protein kinase, regulates the G2 checkpoint in response to DNA damage. Preclinical studies have elucidated the role of wee1 in DNA damage repair and the stabilization of replication forks, supporting the validity of wee1 inhibition as a viable therapeutic target in cancer. MK-1775, a selective and potent small-molecule inhibitor of wee1, is under clinical development as a potentiator of DNA damage caused by cytotoxic chemotherapies. We present a review of the role of wee1 in the cell cycle and DNA replication and summarize the clinical development to date of this novel class of anticancer agents. 相似文献
17.
Do Geum-Sook Seo Bong-Bo Ko Jong-Min Lee Seon-Hee Pak Jae-Hong Kim In-Sun Song Seung-Dal 《Plant Cell, Tissue and Organ Culture》1999,57(2):113-119
The effects of basal media and growth regulators on callus initiation and shoot regeneration have been investigated in wild
Allium tuberosum (2n = 4x = 32). Callus initiation was greatest from flower bud explants cultured on MS medium supplemented
with 2,4-D and BA at 1 mg l−1 each. Maximum number of shoots was obtained from callus grown on MS medium supplemented with NAA and BA at 0.2 and 2 mg l−1, respectively. The chromosome analysis of regenerants derived from callus revealed variation in ploidy, such as 2n = 28,
29, 30, 31, 33 as well as normal tetraploid. During the culture period for two generations, one aneuploid regenerant with
2n = 30 (named At30) showed better viability and growth than tetraploid plants and other aneuploid variants. In a karyotypic
analysis of At30, the chromosomal positions of 5S and 18S-5.8S-26S rDNA were physically mapped by fluorescent in situ hybridization
and compared to chromosomes of wild type A. tuberosum. Both wild type A. tuberosum and At30 exhibited two sets of 5S rDNA
sites, one on the proximal position of the short arm of chromosome 3, and the other on the intercalary region on the long
arm of chromosome 6. There was one 18S-5.8S-26S rDNA site in the secondary constriction including flanking short chromosomal
segments of satellite and terminal regions on the short arm of chromosome 8 in wild type A. tuberosum. However, At30 showed
only three labelled chromosome 8 indicating that this was one of the lost chromosomes of At30.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
18.
Helicobacter pylori Activates IL‐6‐STAT3 Signaling in Human Gastric Cancer Cells: Potential Roles for Reactive Oxygen Species 下载免费PDF全文
19.
Lymphoma development of simultaneously combined exposure to two radiofrequency signals in AKR/J mice
Lee HJ Jin YB Lee JS Choi SY Kim TH Pack JK Choi HD Kim N Lee YS 《Bioelectromagnetics》2011,32(6):485-492
There are public concerns regarding possible carcinogenic or cancer-promoting effects of radiofrequency electromagnetic fields (RF-EMFs) because of the extensive use of wireless mobile phones and other telecommunication devices in daily life. However, so far it is unclear if non-thermal exposure of single EMF exposure in animal studies has a direct influence on carcinogenesis. Here, carcinogenic effects of combined signal RF-EMFs on AKR/J mice, which were used for the lymphoma animal model, were investigated. Six-week-old AKR/J mice were simultaneously exposed to two types of RF signals: single code division multiple access (CDMA) and wideband code division multiple access (WCDMA). AKR/J mice were exposed to combined RF-EMFs for 45 min/day, 5 days/week, for a total of 42 weeks. The whole-body average specific absorption rate (SAR) of CDMA and WCDMA fields was 2.0 W/kg each, 4.0 W/kg in total. When we examined final survival, lymphoma incidence, and splenomegaly incidence, no differences were found between sham- and RF-exposed mice. However, occurrence of metastasis infiltration to the brain in lymphoma-bearing mice was significantly different in RF-exposed mice when compared to sham-exposed mice, even though no consistent correlation (increase or decrease) was observed between male and female mice. However, infiltration occurrence to liver, lung, and spleen was not different between the groups. From the results, we suggested that simultaneous exposure to CDMA and WCDMA RF-EMFs did not affect lymphoma development in AKR/J mice. 相似文献
20.
Epstein-Barr virus (EBV) is associated with human cancers such as nasopharyngeal carcinoma, Burkitt’s lymphoma, Hodgkin’s
disease, and gastric carcinoma (GC). EBV is associated with about 10% of all GC cases globally. EBV-associated GC has distinct
features from EBV-negative GC. However, it is still unclear if EBV infection has any effect on GC chemoresistance. Cell proliferation
assay, cell cycle analysis, and active caspase Western blot revealed that the EBV-positive GC cell line (AGS-EBV) showed chemoresistance
to docetaxel compared to the EBV-negative GC cell line (AGS). Docetaxel treatment increased expression of Bax similarly in
AGS and AGS-EBV cell lines. However, Bcl-2 induction was markedly higher in AGS-EBV cells, after docetaxel treatment. Although
docetaxel increased the expression of p53 to a similar extent in both cell lines, induction of p21 in AGS-EBV cells was lower
than in AGS cells. Furthermore, expression of survivin was higher in AGS-EBV cells than in AGS cells following docetaxel treatment
as well as at basal state. EBVlytic gene expression was induced by docetaxel treatment in AGS-EBV cells. The results suggest
that EBV infection and lytic induction confers chemoresistance to GC, possibly by regulating cellular and EBV latent and lytic
gene expression. 相似文献