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2.
Victoria L. Parker Matthew C. Winter John A. Tidy Barry W. Hancock Julia E. Palmer Naveed Sarwar Baljeet Kaur Katie McDonald Xianne Aguiar Kamaljit Singh Nick Unsworth Imran Jabbar Allan A. Pacey Robert F. Harrison Michael J. Seckl 《International journal of cancer. Journal international du cancer》2023,152(5):986-997
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus. 相似文献
3.
Lauren Tingey Britta Mullany Rachel Chambers Ranelda Hastings Angelita Lee Anthony Parker 《AIDS care》2015,27(9):1087-1097
Potential for widespread transmission of HIV/AIDS among American Indian (AI) adolescents exists, yet no evidence-based interventions (EBIs) have been adapted and evaluated with this population. Intensive psychoeducation may improve knowledge and decision-making which could potentially translate to reductions in HIV risk behaviors. A peer group randomized controlled comparison of an adapted EBI vs. control was delivered over an eight-day summer basketball camp in one reservation-based tribal community to adolescents ages 13–19. Outcome data were gathered immediately post-camp and at 6 and 12 months follow-up. Self-selected peer groups were randomized to intervention (n = 138) or control (n = 129) conditions for a total sample of 267 participants (56.2% female), mean age 15.1 years (SD = 1.7). Intervention participants had better condom use self-efficacy post-camp (Adjusted Mean Difference [AMD] = ?0.75, p < 0.005) and at 6 (AMD = ?0.44, p < 0.005) and 12 months (AMD = ?0.23, p < 0.05) follow-up. Intervention participants also had higher HIV prevention and transmission knowledge (post-camp: AMD = 0.07, p < 0.01; 6 months: AMD = 0.06, p < 0.01) were more likely to believe condoms prevent sexually transmitted infections (post-camp: RR = 1.41, p < 0.005; 6 months: RR = 1.34, p < 0.05), to talk with an adult about HIV/AIDS (post-camp: RR=1.78, p < 0.005; 6 months: RR = 1.14, p < 0.005), had higher partner negotiation efficacy related to substance use during sex (post-camp: AMD = 0.37, p < 0.01), and were more likely to intend to use a condom (post-camp: RR = 1.39, p < 0.01). The adapted intervention had short- and medium-term impacts on AI adolescent risk for HIV/AIDS, but attenuated at 12 months. Intervention delivery through a community-based camp is feasible and acceptable with strong retention. Additional study is needed to evaluate the adapted intervention's impact on sexual risk behaviors and if booster sessions and parent involvement translate to long-term impacts. 相似文献
4.
Jeffrey Buenaflor Parker Sommerville Hang Qian Christine Luscombe 《Macromolecular chemistry and physics.》2020,221(2)
A comparative study involving bimetallic nickel catalysts designed from disubstituted N,N,N′,N′‐tetra(diphenylphosphanylmethyl)benzene diamine bridging ligands is reported. Catalyst behavior is explored in the Kumada catalyst‐transfer polymerization (KCTP) using poly(3‐hexylthiophene) (P3HT) as the model system. The success of a controlled polymerization is monitored by analyzing monomer conversion, degree of polymerization, end‐group identity, and molecular weight distribution. The characterization of P3HT obtained from KCTP initiated with the bimetallic catalysts shows chain‐growth behavior; however, the presence of Br/Br end‐groups and broader molecular weight distribution reveals a reduced controlled polymerization compared to the commonly employed Ni(dppp)Cl2. The observed increase in intermolecular chain transfer and termination processes in KCTP initiation with the bimetallic catalysts can be attributed to a weaker Ni(0)‐π‐aryl complex interaction, which is caused by increased steric crowding of the coordination sphere. 相似文献
5.
Purpose
Chest wall pain is an uncommon but bothersome late complication following lung stereotactic body radiation therapy. Despite numerous studies investigating predictors of chest wall pain, no clear consensus has been established for a chest wall constraint. The aim of our study was to investigate factors related to chest wall pain in a homogeneous group of patients treated at our institution.Patients and methods
All 122 patients were treated with the same stereotactic body radiation therapy regimen of 48 Gy in three fractions, seen for at least 6 months of follow-up, and planned with heterogeneity correction. Chest wall pain was scored according to the Common Terminology Criteria for Adverse Events classification v3.0. Patient (age, sex, diabetes, osteoporosis), tumour (planning target volume, volume of the overlapping region between planning target volume and chest wall) and chest wall dosimetric parameters (volumes receiving at least 30, 40, and 50 Gy, the minimal doses received by the highest irradiated 1, 2, and 5 cm3, and maximum dose) were collected. The correlation between chest wall pain (grade 2 or higher) and the different parameters was evaluated using univariate and multivariate logistic regression.Results
Median follow-up was 18 months (range: 6–56 months). Twelve patients out of 122 developed chest wall pain of any grade (seven with grade 1, three with grade 2 and two with grade 3 pain). In univariate analysis, only the volume receiving 30 Gy or more (P = 0.034) and the volume of the overlapping region between the planning target volume and chest wall (P = 0.038) significantly predicted chest wall pain, but these variables were later proved non-significant in multivariate regression.Conclusion
Our analysis could not find any correlation between the studied parameters and chest wall pain. Considering our present study and the wide range of differing results from the literature, a reasonable conclusion is that a constraint for chest wall pain is yet to be defined. 相似文献6.
Dynamic LVOT Obstruction and Aortic Stenosis in the Same Patient: A Case of Challenging Doppler Hemodynamics
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Matthew W. Parker M.D. Francis J. Kiernan M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1030-1032
We present a patient with both dynamic left ventricular outflow tract obstruction and valvular aortic stenosis. The aortic valve was calcified, and velocities and gradients measured by continuous‐wave Doppler met standard criteria for severe aortic stenosis. The increased subvalvular velocities invalidated assumptions of the simplified Bernoulli equation; correction using the longer form of the Bernoulli equation suggested a lower but still significant gradient. The complex shape of the subvalvular spectral Doppler envelope indicated supranormal systolic function and dynamic left ventricular outflow obstruction. Left heart catheterization with an end‐hole catheter was required to determine the subvalvular and valvular components of the obstruction. 相似文献
7.
目的:应用99mTc-DTPA肾动脉显像评价Stanford不同分型主动脉夹层患者术后左、右侧肾功能及总体肾功能受损程度,帮助临床制定进一步的治疗方案,改善患者预后。方法:回顾性分析2018年3月8日至2019年7月19日,在本院核医学科行99mTc-DTPA肾动态显像的主动脉夹层术后患者48例,评价患者双肾血流灌注、总肾小球滤过率(GFR)和分肾的GFR,比较Stanford主动脉夹层A型(简称A型)患者和主动脉夹层B型(简称B型)患者之间总肾功能及分肾功能,血肌酐、血尿素氮及血尿酸水平的差异。结果:B型患者术后总GFR低于A型患者(67.5 vs.80.6 m L/min,P<0.05),其中以左肾功能受损为著(30.9 vs.40.3 m L/min,P<0.05),差异有统计学意义。结论:肾动态显像对主动脉夹层术后患者早期评价肾功能有重要价值。主动脉夹层B型患者GFR较A型减低,且左侧肾GFR减低更明显,临床可以早期采取干预措施,改善主动脉夹层患者预后。 相似文献
8.
痤疮可辨为阴、阳两证。阳疮者,缘患者劳汗被寒、玄府闭合,汗脂凝聚日久不得外排,蕴热搏结气血而生疮化腐,疮症为热为痛,此为易治;阴疮者,由阳疮转化而来,缘患者外感寒风、内伤生冷,且医者又重用寒凉、失于托透,以至气血冰凝,久不溃脓或溃脓难出,此为难治。根据难治性痤疮临床表现,其多类属于阴疮,以阳虚表郁、邪闭毛窍为致病之关键,其中表郁毛窍、邪闭肌腠为病之标,阳虚阴凝为病之本。治疗当以温阳透发、祛邪外达为法。以麻黄附子细辛汤温阳化阴滞、发阳透毒治其本,待阴邪发越,即用火针强开门户、消疮排脓治其标。标本兼治、针药结合的方法治疗难治性痤疮在临床中能够安全有效地消除痤疮、改善皮损、降低复发率。 相似文献
9.