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1.
Masayo Suzuki Hiroyuki Ishida Yukimasa Shiotsu Taisuke Nakata Shiro Akinaga Shigemitsu Takashima Toshiaki Utsumi Toshiaki Saeki Nobuhiro Harada 《The Journal of steroid biochemistry and molecular biology》2009,113(3-5):195-201
In order to evaluate the importance of estrogen production in tumor and surrounding tissues, we measured mRNA expression levels of 5 enzymes participating to estrogen synthesis in situ and 4 breast cancer-related proteins in 27 pairs of tumor and non-malignant tissues. Steroid sulfatase (STS) mRNA was more frequently detected in tumor tissues rather than in their non-malignant counterparts. Estrogen sulfotransferase (EST) was constantly expressed with high level not only in tumor tissues but also in their surrounding non-malignant counterparts. In contrast, mRNA expression levels of aromatase, and 17β-hydroxysteroid dehydrogenase type I and II were relatively low and detected only in small proportion of the patients. We also measured the mRNA expression levels of the same nine genes in tumor tissues of 197 breast cancer patients, and analyzed relationship between the mRNA expression level and the clinicopathological parameters. The mRNA expression levels of STS, aromatase and erbB2 in tumor tissues increased as breast cancer progressed. The tumoral mRNA expression levels of STS, estrogen receptor β, and erbB2 in patients with recurrence were higher than those in patients without recurrence. Upregulation of STS expression plays an important role in tumor progression of human breast cancer and is considered to be responsible for estrogen production in tumor and surrounding tissues. 相似文献
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Ruxandra Ion L. Telvi Jean-Louis Chaussain Jacques Patrick Barbet Manoel Nunes Anne Safar Marie-Odile Réthoré Marc Fellous Ken McElreavey 《Human genetics》1998,102(2):151-156
In 46,XY individuals, testes are determined by the activity of the SRY gene (sex-determining region Y), located on the short arm of the Ychromosome. The other genetic components of the cascade
that leads to testis formation are unknown and may be located on the Xchromosome or on the autosomes. Evidence for the existence
of several loci associated with failure of male sexual development is indicated by reports of 46,XY gonadal dysgenesis associated
with structural abnormalities of the Xchromosome or of autosomes (chromosomes9, 10, 11 and 17). In this report, we describe
the investigation of a child presenting with multiple congenital abnormalities, mental retardation and partial testicular
failure. The patient had a homogeneous de novo 46,XY,inv dup(9)(pter→p24.1::p21.1 →p23.3::p24.1→qter) chromosome complement.
No deletion was found by either cytogenetic or molecular analysis. The SRY gene and DSS region showed no abnormalities. Southern blotting dosage analysis with 9p probes and fluorescent in situ hybridisation data
indicated that the distal breakpoint of the duplicated fragment was located at 9p24.1, proximal to the SNF2 gene. We therefore suggest that a gene involved in normal testicular development and/or maintenance is present at this position
on chromosome 9.
Received: 20 January 1997 / Accepted: 5 November 1997 相似文献
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Ken Muneoka 《Developmental biology》1980,74(2):486-489
Pasteur pipets were prepared with constricted tips of such diameter that unfertilized Ciona intestinalis (L.) eggs could be held immobile while their chorions were lanced open with a tungsten needle. Eggs were pretreated with double-strength seawater to increase the space between egg and chorion. Eighty-five percent of the eggs dechorionated in this way developed normally after fertilization in regular seawater. 相似文献
6.
Antoine Wystrach Sebastian Schwarz Patrick Schultheiss Guy Beugnon Ken Cheng 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(2):167-179
The Australian desert ant Melophorus bagoti often follows stereotypical routes through a cluttered landscape containing both distant panoramic views and obstacles (plants)
to navigate around. We created an artificial obstacle course for the ants between a feeder and their nest. Landmarks comprised
natural objects in the landscape such as logs, branches, and tussocks. Many ants travelled stereotypical routes home through
the obstacle course in training, threading repeatedly the same gaps in the landmarks. Manipulations altering the relations
between the landmarks and the surrounding panorama, however, affected the routes in two major ways. Both interchanging the
positions of landmarks (transpositions) and displacing the entire landmark set along with the starting position of the ants
(translations) (1) reduced the stereotypicality of the route, and (2) increased turns and meanders during travel. The ants
might have used the entire panorama in view-based travel, or the distal panorama might prime the identification and use of
landmarks en route. Despite the large data set, both options (not mutually exclusive) remain viable. 相似文献
7.
Arash Masbough Kevin Frankowski Ken J. Hall Sheldon J.B. Duff 《Ecological Engineering》2005,25(5):552
Percolation of rainfall through woodwaste piles leaches natural chemicals from the wood residuals that can have adverse impacts on the environment. A study was conducted on a woodwaste storage site, adjacent to the Lower Fraser River, near Mission, BC, Canada. The objective of this research was to evaluate the effectiveness of constructed wetland for treatment of this woodwaste leachate. The leachate was characterized by high oxygen demand, tannin and lignin, and volatile fatty acids (VFAs), but low pH and nutrients. Diluted leachate passed through six pilot-scale wetland cells, four planted with cattail (Typha latifolia) and two unplanted controls, with a hydraulic retention time of 7 days and an average depth of 40 cm. Nutrient addition and pH adjustments were made to improve contaminant removal. Reductions in contaminants were consistently achieved, with average removals for BOD, COD, VFAs and tannin and lignin of 60, 50, 69 and 42%, respectively. Climatic conditions had an impact on the performance of the constructed wetland. Further operation of the system will help to elucidate the seasonal fluctuations. Aging of the constructed wetland system increased the treatment performance. 相似文献
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Gillian D Alton David L Pearl Ken G Bateman W Bruce McNab Olaf Berke 《BMC veterinary research》2010,6(1):42