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1.
Rajiv V. Dave Baek Kim Alona Courtney Rachel OConnell Tim Rattay Vicky P. Taxiarchi Jamie J. Kirkham Elizabeth M. Camacho Patricia Fairbrother Nisha Sharma Christopher W. J. Cartlidge Kieran Horgan Stuart A. McIntosh Daniel R. Leff Raghavan Vidya Shelley Potter Chris Holcombe Ellen Copson Charlotte E. Coles Ramsey I. Cutress Ashu Gandhi Cliona C. Kirwan 《British journal of cancer》2021,124(11):1785
Background The B-MaP-C study aimed to determine alterations to breast cancer (BC) management during the peak transmission period of the UK COVID-19 pandemic and the potential impact of these treatment decisions.Methods This was a national cohort study of patients with early BC undergoing multidisciplinary team (MDT)-guided treatment recommendations during the pandemic, designated ‘standard’ or ‘COVID-altered’, in the preoperative, operative and post-operative setting.Findings Of 3776 patients (from 64 UK units) in the study, 2246 (59%) had ‘COVID-altered’ management. ‘Bridging’ endocrine therapy was used (n = 951) where theatre capacity was reduced. There was increasing access to COVID-19 low-risk theatres during the study period (59%). In line with national guidance, immediate breast reconstruction was avoided (n = 299). Where adjuvant chemotherapy was omitted (n = 81), the median benefit was only 3% (IQR 2–9%) using ‘NHS Predict’. There was the rapid adoption of new evidence-based hypofractionated radiotherapy (n = 781, from 46 units). Only 14 patients (1%) tested positive for SARS-CoV-2 during their treatment journey.Conclusions The majority of ‘COVID-altered’ management decisions were largely in line with pre-COVID evidence-based guidelines, implying that breast cancer survival outcomes are unlikely to be negatively impacted by the pandemic. However, in this study, the potential impact of delays to BC presentation or diagnosis remains unknown.Subject terms: Breast cancer, Surgical oncology, Health care economics, Quality of life, Health policy 相似文献
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Amani Nassar Yosria El Gohary Fatma El-Desoky 《Journal of cosmetic and laser therapy》2016,18(6):330-334
Striae distensae (SD) is a challenging cosmetic problem for which various treatment modalities have been applied. Our aim was to evaluate the efficacy and tolerability of needling therapy versus microdermabrasion with sonophoresis in the treatment of SD. Materials and methods: Forty female patients with SD (mean duration 2.98 ± 2.66) were enrolled in this study. Patients were assigned to two groups, Group 1 treated with needling therapy and Group 2 treated by microdermabrasion with sonophoresis. In Group 1, three sessions of needling therapy were performed for each patient with 4-week interval between the sessions, while in Group 2, ten sessions of combined microdermabrasion and sonophoresis were performed for each patient. Skin biopsies were taken from the most atrophic site stained with hematoxylin and eosin stain and Masson trichrome stains to study the histopathological changes and efficacy of treatment, respectively. Results: There was a significant clinical improvement in SD in Group 1 compared with Group 2. Amount of collagen, number of fibroblasts, and epidermal thickness increased in the dermis at the end of treatment sessions (90% in Group 1 compared to 50% in Group 2). Conclusion: Needling therapy is an easy, safe, and economic method and considered as a suitable modality in management of striae. 相似文献
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An-Qin Vicky Dong 《Developmental neurorehabilitation》2016,19(5):275-283
Objective: To investigate the effects of ‘remind to move’ treatment on hemiplegic arm function in children with unilateral cerebral palsy (CP). Methodology: Twelve students with unilateral CP aged 6–18 were recruited from a special school and randomly assigned into two groups. Participants in the experimental group underwent a 3-week sensory cueing treatment followed by a 3-week sham treatment. Participants in the waitlist group completed the sham treatment first followed by the sensory-cueing treatment. There was a 4-week washout period between treatments. Results: Both functional hand use and arm impairment level significantxly improved after the 3-week sensory cueing treatment for the combined sample between groups. However, no significant carryover effects were found for either treatment. Conclusion: Three weeks of ‘remind to move’ treatment is useful in improving hemiplegic arm function and quantity of hand use in children with unilateral CP but the long-term carryover effect requires further investigation. 相似文献
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Vicky G. Kastbjerg Line Hein-Kristensen Lone Gram 《Antimicrobial agents and chemotherapy》2014,58(6):3124-3132
Exposure of the human food-borne pathogen Listeria monocytogenes to sublethal concentrations of triclosan can cause resistance to several aminoglycosides. Aminoglycoside-resistant isolates exhibit two colony morphologies: normal-size and pinpoint colonies. The purposes of the present study were to characterize the small colonies of L. monocytogenes and to determine if specific genetic changes could explain the triclosan-induced aminoglycoside resistance in both pinpoint and normal-size isolates. Isolates from the pinpoint colonies grew poorly under aerated conditions, but growth was restored by addition of antibiotics. Pinpoint isolates had decreased hemolytic activity under stagnant conditions and a changed spectrum of carbohydrate utilization compared to the wild type and isolates from normal-size colonies. Genome sequence comparison revealed that all seven pinpoint isolates had a mutation in a heme gene, and addition of heme caused the pinpoint isolates to revert to normal colony size. Triclosan-induced gentamicin-resistant isolates had mutations in several different genes, and it cannot be directly concluded how the different mutations caused gentamicin resistance. However, since many of the mutations affected proteins involved in respiration, it seems likely that the mutations affected the active transport of the antibiotic and thereby caused resistance by decreasing the amount of aminoglycoside that enters the bacterial cell. Our study emphasizes that triclosan likely has more targets than just fabI and that exposure to triclosan can cause resistance to antibiotics that enters the cell via active transport. Further studies are needed to elucidate if L. monocytogenes pinpoint isolates could have any clinical impact, e.g., in persistent infections. 相似文献
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T. E. Graedel E. M. Harper N. T. Nassar Barbara K. Reck 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(20):6295-6300
It is indisputable that modern life is enabled by the use of materials in its technologies. Those technologies do many things very well, largely because each material is used for purposes to which it is exquisitely fitted. The result over time has been a steady increase in product performance. We show that this materials complexity has markedly increased in the past half-century and that elemental life cycle analyses characterize rates of recycling and loss. A further concern is that of possible scarcity of some of the elements as their use increases. Should materials availability constraints occur, the use of substitute materials comes to mind. We studied substitution potential by generating a comprehensive summary of potential substitutes for 62 different metals in all their major uses and of the performance of the substitutes in those applications. As we show herein, for a dozen different metals, the potential substitutes for their major uses are either inadequate or appear not to exist at all. Further, for not 1 of the 62 metals are exemplary substitutes available for all major uses. This situation largely decouples materials substitution from price, thereby forcing material design changes to be primarily transformative rather than incremental. As wealth and population increase worldwide in the next few decades, scientists will be increasingly challenged to maintain and improve product utility by designing new and better materials, but doing so under potential constraints in resource availability.The degree to which the materials of modern technology enable and improve our state of life is not adequately appreciated. A century ago, or even half a century ago, less than 12 materials were in wide use: wood, brick, iron, copper, gold, silver, and a few plastics. Today, however, substantial materials diversity in products of every kind is the rule rather than the exception. [A modern computer chip, for example, employs more than 60 different elements (1).] This use of materials is not a whim of the designer, but a carefully calculated effort to achieve increasingly high performance in products simple to complex. 相似文献
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PURPOSE: The purpose of this longitudinal study was to determine factors associated with mutans streptococci (MS) infection and development of caries lesions in a group of children 21 to 72 months old. METHODS: The 63 caries-free children, recruited since birth, were divided into: (1) a study group of 24 children who were colonized with MS; and (2) a control group of 39 children without MS. The children were recalled every 3 months for approximately 24 months, and their social, medical, and dental histories were updated. At each recall, the teeth were checked for presence or absence of plaque, enamel hypoplasia, and caries lesions, and their MS status was assessed using a commercial test kit. RESULTS: MS infection was associated with: (1) visible plaque (P < .01); (2) enamel hypoplasia (P < .05); (3) commencement of tooth-brushing after 12 months of age (P < .05); (4) lack of parental assistance with tooth-brushing (P < .025); and (5) increased hours of child care/school (P < .05). Four children (20%) were colonized at an age range of 21 to 36 months, 9 (45%) at 37 to 48 months, and 7 (35%) at 49 to 72 months (P < .001). Eight children who developed caries lesions: (1) had more hypoplastic teeth (P < .001); (2) ate sugar-containing snacks (P < .05); and (3) did not brush regularly with chlorhexidine gel (P < .01) compared to those who remained free of caries lesions. CONCLUSIONS: Lack of oral hygiene, consumption of sugar-containing snacks, and enamel hypoplasia are significant factors for both MS infection and caries lesion initiation. 相似文献
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BACKGROUND: Tacrolimus, an immunosuppressive drug used in organ transplantation, has been reported not to induce gingival overgrowth. However, prevalence studies are limited, and the methods used for assessing gingival overgrowth varies among studies. OBJECTIVE: The purpose of this study was to evaluate the effects of up to 240 days of tacrolimus therapy on gingival tissues of rats. MATERIALS AND METHODS: Rats were treated for 60, 120, 180 and 240 days with daily subcutaneous injections of 1 mg/kg body weight of tacrolimus. After histological processing, the oral and connective tissue, volume densities of fibroblasts (Vf), collagen fibers (Vcf) and other structures (Vo) were assessed in the region of the lower first molar. RESULTS: After 60 and 120 days of treatment with tacrolimus, gingival overgrowth was not observed. The gingival epithelium, connective tissue, as well as the values for Vf, Vcf, and Vo were similar to those of the control rats (P>0.05). After 180 and 240 days of the treatment, gingival overgrowth was associated with a significant increase in the gingival epithelium and connective tissue as well as an increase in the Vf and Vcf (P<0.05). CONCLUSIONS: Within the limits of the experimental study, it may be concluded that the deleterious side effects of tacrolimus on the gingival tissues of rats may be time-related. 相似文献
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Gogos C Theodorou V Economides N Beltes P Kolokouris I 《Journal of endodontics》2008,34(11):1385-1387
The aim of this study was to evaluate the relative bond strengths of AH-26 and Epiphany sealers to both Resilon and composite resin. Four groups of substrate/bonded sealer combinations were tested: group A, composite resin substrate + Epiphany sealer; group B, composite resin substrate + AH-26 sealer; group C, Resilon substrate + Epiphany sealer; and group D, Resilon substrate + AH-26 sealer. Bond strength was evaluated in shear mode by using a universal testing machine at a crosshead speed of 0.5 mm/min. Statistical analysis (Kruskall-Wallis and Dunn tests) showed that the bond strength of AH-26 to both substrates was significantly greater than the bond strength of Epiphany. Therefore, the monoblock in the root canal might be more effectively achieved by combining Resilon core material with the epoxy resin-based sealer (AH-26) rather than Epiphany sealer. 相似文献