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71.
To evaluate potential clinical applications of nonautologous fibrin glue (FG) as a hemostatic agent in vascular surgery, we compared its efficacy to oxidized regenerated cellulose (OC) in hemostatically sealing polytetrafluoroethylene (PTFE) vascular graft anastomoses. PTFE grafts (4 mm wide and 4 to 6 cm in length) were placed to each femoral artery in a heparinized canine model, in end-to-end fashion in half of the dogs and in end-to-side fashion in the remaining dogs. Each set of graft-arterial anastomoses was then sealed with either FG or OC, determined randomly, followed by simultaneous measurement of blood loss through the graft anastomoses and needle holes. There was significantly less bleeding from anastomoses sealed with FG compared with those sealed with OC, regardless of whether the anastomoses sealed with FG compared with those sealed with OC, regardless of whether the anastomosis was constructed in end-to-end (p less than 0.03) or end-to-side (p less than 0.004) fashion; overall, the operative blood loss for grafts sealed with FG was 14 +/- 6 (mean +/- standard error of the mean) vs 99 +/- 27 ml/min for those sealed with OC (p less than 0.001). In the early postoperative period, significant groin hematomas occurred more frequently in grafts sealed with OC compared with those sealed with FG. Microscopic examination of graft-arterial specimens harvested at postoperative intervals ranging from 1 day to 3 months revealed no significant inflammatory reaction with either hemostatic agent; after 2 to 3 weeks, paired specimens appeared histologically similar despite previous treatment with either FG or OC.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
72.
Heather D. Hadjistavropoulos Vanessa Peynenburg David L. Thiessen Marcie Nugent Eyal Karin Lauren Staples Blake F. Dear Nickolai Titov 《Revue canadienne de psychiatrie》2022,67(3):192
Objective:There is strong evidence supporting internet-delivered cognitive behaviour therapy (iCBT) and consequently growing demand for iCBT in Canada. Transdiagnostic iCBT that addresses both depression and anxiety is particularly promising as it represents an efficient method of delivering iCBT in routine care. The Online Therapy Unit, funded by the Saskatchewan government, has been offering transdiagnostic iCBT for depression and anxiety since 2013. In this article, to broadly inform implementation efforts, we examined trends in utilization, patient characteristics, and longitudinal improvements for patients receiving transdiagnostic iCBT over 6 years.Methods:Patients who completed telephone screening between November 2013 and December 2019 were included in this observational study. Patients provided demographics and mental health history at screening and completed measures at pre-treatment, post-treatment and at 3- to 4-month follow-up. Treatment engagement and satisfaction were assessed.Results:A total of 5,321 telephone screenings were completed and 4,283 of patients were accepted for treatment over the 6-year period (80.5% acceptance). The most common reason for referral to another service was high suicide risk/severe symptoms (47.1%). Examination of trends showed growing use of transdiagnostic iCBT over time (37% increase per year). There was remarkable stability in patient characteristics across years. Most patients were concurrently using medication (57.3%) with 11.9% reporting using iCBT while on a waiting list for face-to-face treatment highlighting the importance of integrating iCBT with other services. Consistent across years, large improvements in depression and anxiety symptoms were found and maintained at 3- to 4-month follow-up. There was strong patient engagement with iCBT and positive ratings of treatment experiences.Conclusions:As there is growing interest in iCBT in Canada, this large observational study provides valuable information for those implementing iCBT in terms of likely user characteristics, patterns of use, and improvements. This information has potential to assist with resource allocation and planning in Canada and elsewhere. 相似文献
73.
Helen A Snooks Bridie Angela Evans David Cohen Michael Nugent Frances Rapport Jon Skone Angie Meredith Tricia Davies Diana O'Sullivan 《BMC public health》2011,11(1):25
Background
Inequalities in health have proved resistant to 'top down' approaches. It is increasingly recognised that health promotion initiatives are unlikely to succeed without strong local involvement at all stages of the process and many programmes now use grass roots approaches. A healthy living approach to community development (HLA) was developed as an innovative response to local concerns about a lack of appropriate services in two deprived communities in Pembrokeshire, West Wales. We sought to assess feasibility, costs, benefits and working relationships of this HLA. 相似文献74.
Purpose
There is strong evidence supporting the importance of the volume–outcome relationship with respect to lung and pancreatic cancers. This relationship for rectal cancer surgery however remains unclear. We review the currently available literature to assess the evidence base for volume outcome in relation to rectal cancer surgery. 相似文献75.
76.
In this perspective, we first review some of the published literature on structural modeling of the mechanical properties of the lung parenchyma. Based on a recent study, we demonstrate why mechanical dysfunction accompanying parenchymal diseases such as pulmonary fibrosis and emphysema can follow a very different course from the progression of the underlying microscopic pathophysiology itself, particularly in the early stages. The key idea is related to the concept of percolation on elastic networks where the bulk modulus of the network suddenly changes when the fibrotic stiff regions or the emphysematous holes become suddenly connected across the network. We also introduce the concept of depercolation as a basis for the rational optimization of tissue repair. Specifically, we use these network models to predict the functional improvements that a hypothetical biological or tissue engineering repair could achieve. We find that rational targeted repair can have significant benefits over generic random repair. This concept may find application in the treatment of lung fibrosis, surgical, bronchoscopic, or biological lung volume reduction, or any future alveolar regeneration or tissue engineering solution to the repair of connective tissue damage of the lung. 相似文献
77.
Luke M Geever Ciaran C Cooney John G Lyons James E Kennedy Michael J D Nugent Sinead Devery Clement L Higginbotham 《European journal of pharmaceutics and biopharmaceutics》2008,69(3):1147-1159
Hydrogel based devices belong to the group of swelling controlled drug delivery systems. Temperature responsive poly(N-isopropylacrylamide)-poly(vinylpyrrolidinone) random copolymers were produced by free radical polymerisation, using 1-hydroxycyclohexylphenyketone as an ultraviolet-light sensitive initiator, and poly(ethylene glycol) dimethacrylate as the crosslinking agent (where appropriate). The hydrogels were synthesised to have lower critical solution temperatures (LCST) near body temperature, which is favourable particularly for 'smart' drug delivery applications. Two model drugs (diclofenac sodium and procaine HCl) were entrapped within these xerogels, by incorporating the active agents prior to photopolymerisation. The properties of the placebo samples were contrasted with the drug-loaded copolymers at low levels of drug integration. Modulated differential scanning calorimetry (MDSC), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and atomic force microscopy (AFM) were used to investigate the influence of the drugs incorporated on the solid-state properties of the xerogels. MDSC and swelling studies were carried out to ascertain their effects on the LCST and swelling behaviour of the hydrated samples. In all cases, drug dissolution analysis showed that the active agent was released at a slower rate at temperatures above the phase transition temperature. Finally, preliminary in vitro cytotoxicity evaluations were performed to establish the toxicological pattern of the gels. 相似文献
78.
C E Nugent 《Current opinion in obstetrics & gynecology》1991,3(2):235-241
Advances in molecular genetics are leading to changes in practice that have a direct impact on the obstetrician and gynecologist. New techniques of prenatal screening, diagnosis, and potentially therapy are rapidly evolving. Recent developments in cystic fibrosis, preimplantation genetics, fragile X syndrome, neurofibromatosis, muscular dystrophy, and Marfan syndrome are discussed. 相似文献
79.
80.
S L Hillier M A Krohn R P Nugent R S Gibbs 《American journal of obstetrics and gynecology》1992,166(3):938-944
This study was undertaken to define the characteristics and persistence of vaginal flora in 7918 pregnant women at 23 to 26 weeks' gestation. Vaginal smears were categorized as normal (predominant lactobacilli), intermediate (reduced lactobacilli), or positive for bacterial vaginosis. The women with normal flora were least likely to have elevated vaginal pH, amine odor, milky discharge, or colonization by Gardnerella, Bacteroides, or genital mycoplasmas. Women with intermediate vaginal flora had intermediate frequencies of these clinical signs and microorganisms. Group B streptococci and yeast were associated with normal or intermediate flora, whereas Neisseria gonorrhoeae and Chlamydia trachomatis were recovered more frequently from women with intermediate flora or bacterial vaginosis. Trichomonas vaginalis was most associated with intermediate flora. At follow-up, 81% of the women with normal flora had remained normal. Of the women with intermediate flora, 32% acquired bacterial vaginosis and 30% shifted to normal flora. Only 12% of the women with bacterial vaginosis had shifted to normal flora. We conclude that there are two primary stable vaginal flora patterns (normal flora or bacterial vaginosis) and a third less distinct transitional flora pattern between these two. 相似文献