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31.
TRA Lane HM Moore IJ Franklin AH Davies 《Annals of the Royal College of Surgeons of England》2015,97(2):e18-e20
The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae. 相似文献
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Raimund HM Preidl Tobias Ebker Martin Raithel Falk Wehrhan Friedrich W Neukam Philipp Stockmann 《BMC gastroenterology》2014,14(1):1-6
Background
Cyclooxygenase-2 (COX-2, PTGS2) is an enzyme involved in the synthesis of prostaglandins and thromboxanes, which are regulators of biologic processes such as inflammation, cell proliferation and angiogenesis. COX-2 over-expression was reported in many (pre) malignant tissues, but data strongly vary and seem to depend on the methodology used.Methods
Normal colorectal mucosa and paired cancerous tissue from 60 patients with colorectal cancer was investigated for the levels of COX-2 mRNA by real-time quantitative Polymerase Chain Reaction (qPCR). COX-2 levels were expressed relative to either: tissue weight or levels of the housekeeping genes beta-2 microglobulin (B2M) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH).Results
COX-2 mRNA levels, normalized with respect to tissue weight or mRNA levels of the housekeeping genes B2M or GAPDH, were over-expressed in 80%, 70% and 40% of the colorectal tumor tissues, as compared to the paired adjacent normal colorectal mucosa samples, respectively. Highest mRNA COX-2 ratios tumor/normal were measured when expressed per mg tissue (mean ratio 21.6). When normalized with respect to the housekeeping genes B2M or GAPDH, mean tumor/normal ratios were 16.1 and 7.5, respectively.Conclusion
Expression of COX-2 mRNA levels per mg tissue is most simple in comparison to normalization with respect to the housekeeping genes B2M or GAPDH. Levels of COX-2 mRNA are found over-expressed in almost 80% of the colorectal tumors, compared to paired adjacent normal colorectal mucosa, suggesting a role of COX-2 as a potential biomarker for cancer risk, whereas inhibitors of COX-2 could be of value in chemoprevention of colon cancer. 相似文献35.
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Bone Mass and Strength in School‐Age Children Exhibit Sexual Dimorphism Related to Differences in Lean Mass: The Generation R Study 下载免费PDF全文
Carolina Medina‐Gomez Denise HM Heppe Jia‐Lian Yin Katerina Trajanoska André G Uitterlinden Thomas J Beck Vincent WV Jaddoe Fernando Rivadeneira 《Journal of bone and mineral research》2016,31(5):1099-1106
Bone strength, a key determinant of fracture risk, has been shown to display clear sexual dimorphism after puberty. We sought to determine whether sex differences in bone mass and hip bone geometry as an index of strength exist in school‐age prepubertal children and the degree to which the differences are independent of body size and lean mass. We studied 3514 children whose whole‐body and hip scans were measured using the same densitometer (GE‐Lunar iDXA) at a mean age of 6.2 years. Hip dual‐energy X‐ray absorptiometry (DXA) scans underwent hip structural analyses (HSA) with derivation of bone strength indices. Sex differences in these parameters were assessed by regression models adjusted for age, height, ethnicity, weight, and lean mass fraction (LMF). Whole‐body bone mineral density (BMD) and bone mineral content (BMC) levels were 1.3% and 4.3% higher in girls after adjustment by LMF. Independent of LMF, boys had 1.5% shorter femurs, 1.9% and 2.2% narrower shaft and femoral neck with 1.6% to 3.4% thicker cortices than girls. Consequent with this geometry configuration, girls observed 6.6% higher stresses in the medial femoral neck than boys. When considering LMF, the sexual differences on the derived bone strength indices were attenuated, suggesting that differences in muscle loads may reflect an innate disadvantage in bone strength in girls, as consequence of their lower muscular acquisition. In summary, we show that bone sexual dimorphism is already present at 6 years of age, with boys having stronger bones than girls, the relation of which is influenced by body composition and likely attributable to differential adaptation to mechanical loading. Our results support the view that early life interventions (ie, increased physical activity) targeted during the pre‐ and peripubertal stages may be of high importance, particularly in girls, because before puberty onset, muscle mass is strongly associated with bone density and geometry in children. © 2015 American Society for Bone and Mineral Research. 相似文献
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Nylund A Plarre H Karlsen M Fridell F Ottem KF Bratland A Saether PA 《Archives of virology》2007,152(1):151-179
Summary. In the present study, 24 smolt production sites were screened for the presence of infectious salmon anaemia virus (ISAV) with
the help of a specific real-time RT PCR assay, and 22 of these sites had smolts that were positive. If these smolt production
sites are representative for the prevalence of ISAV in Norwegian smolts, then most marine production sites must be considered
to be positive for ISAV. In addition, 92 European ISAV isolates have been genotyped based on the hemagglutinin-esterase gene
(HE), and their distribution pattern was analysed. This pattern has been coupled to information about the origin of smolt,
eggs, and broodfish in those cases where it has been possible to obtain such information, and with information about ISAV
in neighbouring farms. The pattern suggests that an important transmission route for the ISAV could be that the salmon farming
industry in Norway is circulating some of the isolates in the production cycle, i.e. some sort of vertical or transgenerational
transmission may occur. It has also been shown that avirluent ISAV isolates are fairly common in Norwegian farmed salmon.
Based on this, it is hypothesized that the change from avirulent to virulent ISAV isolates is a stochastic event that is dependent
on the replication frequency of the virus and the time available for changes in a highly polymorphic region (HPR) of the HE
gene to occur. This, and the possibility that only avirluent ISAV isolates are vertically transmitted, may explain why ISA
most often occurs at marine sites and why no more than about 15 farms get ISA every year in Norway. 相似文献
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Serological markers of extracellular matrix remodeling predict transplant‐free survival in primary sclerosing cholangitis 下载免费PDF全文
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Background and Purpose: During repeat-dose toxicity studies, ECGs are collected from chemically or physically-restrained animals over a short timeframe. This is problematic due to cardiovascular changes caused by manual restraint stress and anesthesia, and limited ECG sampling. These factors confound data interpretation, but may be overcome by using a non-invasive jacket-based ECG collection (JET). The current study investigated whether a jacketed external telemetry system could detect changes in cardiac intervals and heart rate in non-human primates (NHPs), previously implanted with a PCT transmitter.Experimental Approach: Twelve male cynomolgus monkeys were treated weekly with vehicle or sotalol (8, 16, 32 mg kg−1) p.o. ECGs were collected continuously for 24 hours, following treatment, over 4 weeks. A satellite group of six NHPs was used for sotalol toxicokinetics.Key Results: Sotalol attained Cmax values 1–3 hours after dosing, and exhibited dose-proportional exposure. In jacketed NHPs, sotalol dose-dependently increased QT/QTc intervals, prolonged PR interval, and reduced heart rate. Significant QTc prolongation of 27, 54 and 76 msec was detected by JET after 8, 16, and 32 mg kg−1 sotalol, respectively, compared with time-matched vehicle-treated animals. Overall, JET-derived PR, QT, QTc intervals, QRS duration, and heart rate correlated well with those derived from PCT.Conclusions and Implications: The current findings clearly support the use of JET to quantify cardiac interval and rhythm changes, capable of detecting QTc prolongation caused by sotalol. JET may be a preferred method compared to restraint-based ECG because high-density ECG sampling can be collected in unstressed conscious monkeys, over several weeks. 相似文献