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51.
Brandon Eilertson Fernanda Maruri Amondrea Blackman Miguel Herrera David C. Samuels Timothy R. Sterling 《Antimicrobial agents and chemotherapy》2014,58(6):3270-3275
Heteroresistance is the coexistence of populations with differing nucleotides at a drug resistance locus within a sample of organisms. Although Sanger sequencing is the gold standard for sequencing, it may be less sensitive than deep sequencing for detecting fluoroquinolone heteroresistance in Mycobacterium tuberculosis. Twenty-seven fluoroquinolone monoresistant and 11 fluoroquinolone-susceptible M. tuberculosis isolates were analyzed by Sanger and Illumina deep sequencing. Individual sequencing reads were analyzed to detect heteroresistance in the gyrA and gyrB genes. Heteroresistance to fluoroquinolones was identified in 10/26 (38%) phenotypically fluoroquinolone-resistant samples and 0/11 (P = 0.02) fluoroquinolone-susceptible controls. One resistant sample was excluded because of contamination with the laboratory strain M. tuberculosis H37Rv. Sanger sequencing revealed resistance-conferring mutations in 15 isolates, while deep sequencing revealed mutations in 20 isolates. Isolates with fluoroquinolone resistance-conferring mutations by Sanger sequencing all had at least those same mutations identified by deep sequencing. By deep sequencing, 10 isolates had a single fixed (defined as >95% frequency) mutation, while 10 were heteroresistant, 5 of which had a single unfixed (defined as <95% frequency) mutation and 5 had multiple unfixed mutations. Illumina deep sequencing identified a higher proportion of fluoroquinolone-resistant M. tuberculosis isolates with heteroresistance than did Sanger sequencing. The heteroresistant isolates frequently demonstrated multiple mutations, but resistant isolates with fixed mutations each had only a single mutation. 相似文献
52.
53.
The Hierarchical Clustering of Clinical Psychology Practicum Competencies: A Multisite Study of Supervisor Ratings 下载免费PDF全文
Craig J. Gonsalvez Frank P. Deane Russell Blackman Michael Matthias Roslyn Knight Yasmina Nasstasia Alice Shires Kathryn Nicholson Perry Christopher Allan Vida Bliokas 《Clinical psychology》2015,22(4):390-403
Competency evaluation rating forms are widely used to assess a range of global and specific psychology practitioner competencies during and at the end of clinical placements. Surprisingly, there is little research examining the dimensional structure or the hierarchical clustering of items on these ratings. The current, multisite study examined supervisor ratings of clinical psychology trainees (N = 204) on the Clinical Psychology Practicum Competencies Rating Scale (CΨPRS). Based on the proximity criterion chosen, hierarchical clustering yielded either nine clusters or four super clusters: Good Practitioner Attributes and Conduct, Scientist Practitioner and Professional Management, Assessment and Intervention, and Psychological Testing. The study also tracked the developmental trajectory of competency attainment. CΨPRS ratings differentiated groups between early but not between later stages of training. Measurement issues and implications for training and practice are discussed. 相似文献
54.
G M Spencer S M Thorpe I R Sargeant G M Blackman J Solano J S Tobias S G Bown 《Gut》1996,39(5):726-731
BACKGROUND: Palliation of malignant dysphagia is possible by a variety of methods although all have significant drawbacks. Laser therapy is an effective and safe treatment but has to be repeated at four to five weekly intervals to maintain palliation. A means of augmenting the benefits while reducing the need for repeat treatments would be highly beneficial to these patients. AIMS: To prospectively explore the safety and efficacy of intraluminal radiotherapy (brachytherapy) when used to augment laser recanalisation for malignant dysphagia. PATIENTS: Nineteen patients with dysphagia due to advanced adenocarcinoma of the oesophagus or cardia were recruited. METHODS: All patients received laser recanalisation until able to swallow a soft diet or better, before the application of a single dose of brachytherapy (10 Gy at 1 cm from the source). Patients were followed up and treated promptly by further endoscopic means in the event of their dysphagia worsening. RESULTS: Six patients (32%) required no further treatment until death at a median of 10 weeks (range 1-20 weeks). Further therapy was required at a median of 11 weeks (range 4-37 weeks) after brachytherapy for those 13 patients with recurrent dysphagia. Subsequent symptom control required endoscopic intervention at an average of once every nine weeks. There was no mortality associated with laser or brachytherapy. Median survival from initial treatment and including the one survivor was 36 weeks (range 5-132 weeks). CONCLUSIONS: Laser plus brachytherapy offers a safe and effective means of palliating malignant dysphagia due to adenocarcinoma, with a longer dysphagia free interval than historical controls treated with laser alone. 相似文献
55.
Longitudinal assessment of serum free testosterone concentration predicts memory performance and cognitive status in elderly men 总被引:15,自引:0,他引:15
Moffat SD Zonderman AB Metter EJ Blackman MR Harman SM Resnick SM 《The Journal of clinical endocrinology and metabolism》2002,87(11):5001-5007
Circulating testosterone (T) levels have behavioral and neurological effects in both human and nonhuman species. Both T concentrations and neuropsychological function decrease substantially with age in men. The purpose of this prospective, longitudinal study was to investigate the relationships between age-associated decreases in endogenous serum T and free T concentrations and declines in neuropsychological performance. Participants were volunteers from the Baltimore Longitudinal Study of Aging, aged 50-91 yr at baseline T assessment. Four hundred seven men were followed for an average of 10 yr, with assessments of multiple cognitive domains and contemporaneous determination of serum total T, SHBG, and a free T index (FTI). We administered neuropsychological tests of verbal and visual memory, mental status, visuomotor scanning and attention, verbal knowledge/language, visuospatial ability, and depressive symptomatology. Higher FTI was associated with better scores on visual and verbal memory, visuospatial functioning, and visuomotor scanning and a reduced rate of longitudinal decline in visual memory. Men classified as hypogonadal had significantly lower scores on measures of memory and visuospatial performance and a faster rate of decline in visual memory. No relations between total T or the FTI and measures of verbal knowledge, mental status, or depressive symptoms were observed. These results suggest a possible beneficial relationship between circulating free T concentrations and specific domains of cognitive performance in older men. 相似文献
56.
Familial congenital bundle branch system disease 总被引:1,自引:0,他引:1
G S Husson M S Blackman M C Rogers S Bharati M Lev 《The American journal of cardiology》1973,32(3):365-369
57.
Transdermal estradiol with oral progestin: biological and clinical effects in younger and older postmenopausal women. 总被引:1,自引:0,他引:1
M F Bellantoni S M Harman V E Cullins S M Engelhardt M R Blackman 《Journal of gerontology》1991,46(6):M216-M222
The purpose of this study was to compare the biochemical and clinical effects of transdermal estrogen replacement therapy (tERT) in younger and older postmenopausal women. We treated 15 younger (less than 60 y) and 13 older (greater than or equal to 60 y) healthy postmenopausal women (45-72 y) with four successive 8-week regimens of tERT at doses of 0 to 150 micrograms/day, combined with cyclic oral medroxyprogesterone acetate (MPA). In both age groups, there were similar (p = .0001) dose-responsive increases in plasma estrogen levels and decreases in LH and FSH levels, although LH values were lower in older women both before and after tERT (p less than .02). The addition of MPA further suppressed LH and, to a lesser extent, FSH in both younger and older women. The ratio of estrogenized to nonestrogenized vaginal cells increased with tERT (p less than .007) in both age groups, but significant symptomatic improvement of vaginal irritation was noted only at the highest tERT dose. Adverse effects unrelated to age included short-term nausea in 4/28 women, and skin irritation at the patch sites in 20/28 women. Vaginal bleeding was of shorter duration, but breast tenderness was more common in older women. Further studies of long-term tERT effects in elderly women are indicated. 相似文献
58.
EH Gemmill DJ Humes JA Catton 《Annals of the Royal College of Surgeons of England》2015,97(3):173-179
Introduction
Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.Methods
A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.Results
From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.Conclusions
The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay. 相似文献59.
Extracellular matrix of cultured bovine aortic endothelial cells contains functionally active type 1 plasminogen activator inhibitor 总被引:17,自引:0,他引:17
The extracellular matrix (ECM) of cultured bovine aortic endothelial cells (BAEs) was analyzed by immunoblotting and reverse fibrin autography and shown to contain type 1 plasminogen activator inhibitor (PAI-1). Most PAI-1 in the ECM formed complexes with exogenously added tissue-type plasminogen activator (tPA), demonstrating that this PAI-1 was functionally active. The resulting tPA/PAI-1 complexes were recovered in the reaction solution, indicating that the PAI-1 in such complexes no longer bound to ECM. The PAI-1 could not be removed by incubating ECM in high salt (2 mol/L NaCl), sugars (1 mol/L galactose, 1 mol/L mannose), glycosaminoglycans (10 mmol/L heparin, 10 mmol/L dermatan sulfate), or epsilon-aminocaproic acid (0.1 mol/L). However, PAI-1 could be extracted from ECM by treatment with either arginine (0.5 mol/L) or potassium thiocyanate (2 mol/L), or by incubation under acidic conditions (pH 2.5). ECM depleted of PAI-1 by acid extraction was able to bind both the active and latent forms of PAI-1. In this instance, most of the bound PAI-1 did not form complexes with tPA, indicating that the latent form was not activated as a consequence of binding to ECM. Although the PAI-1 activity in conditioned medium decayed with a half-life (t 1/2) of less than 3 hours, the t 1/2 of ECM- associated PAI-1 was greater than 24 hours. These data suggest that PAI- 1 is produced by cultured BAEs in an active form and is then either released into the medium where it is rapidly inactivated or into the subendothelium where it binds to ECM. The specific binding of PAI-1 to ECM protects it from this inactivation. 相似文献
60.
Eosinophils stimulate fibroblast DNA synthesis 总被引:9,自引:0,他引:9
Fibrosis complicates a number of chronic inflammatory diseases and occurs in some conditions following chronic hypereosinophilic syndromes. We assessed whether eosinophils might be a source of fibrogenic factors. Extracts of human and guinea pig cell populations enriched for eosinophils contained substances that stimulated tritiated thymidine incorporation by human fibroblasts. Supernatants derived from resting eosinophils and extracts prepared from eosinophil granules also contained fibrogenic factors. Our findings demonstrate a new potential role for eosinophils and suggest a causal relationship between tissue eosinophilia and scar formation in certain parasitic conditions. 相似文献