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1.
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   
2.
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   
3.
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   
4.

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   
5.
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   
6.
7.
There is increasing evidence that the assessment of eosinophilic airway inflammation using induced sputum and measurement of airway hyperresponsiveness provides additional, clinically important information concerning asthma control. The aim of this study was to directly compare the effects of different treatments on these markers in patients with asthma and persistent symptoms, despite the use of low-dose inhaled corticosteroids. A double-blind four-way crossover study was performed, which compared a 1-month treatment with budesonide 400 mug b.i.d., additional formoterol, additional montelukast and placebo in 49 patients with uncontrolled asthma despite budesonide 100 mug b.i.d., with each treatment separated by a 4-week washout period. The change in sputum eosinophil count with formoterol (2.4 to 3.8% change, 0.6-fold reduction, 95% confidence interval (CI) 0.5-0.9) differed significantly from placebo (2.8 to 2.5% change, 1.1-fold reduction, 95% CI 0.7-1.6) and high-dose budesonide (2.7 to 1.6% change, 1.6-fold reduction, 95% CI 1.2-2.2). The effects of montelukast did not differ from placebo. The changes in methacholine airway responsiveness were small and did not differ between treatments. High-dose budesonide had the broadest range of beneficial effects on other outcomes, including symptom scores, morning peak expiratory flow and forced expiratory volume in one second. In conclusion, treatment given in addition to low-dose inhaled corticosteroids results in modest benefits. Formoterol and high-dose budesonide have contrasting effects on eosinophilic airway inflammation.  相似文献   
8.

The Centers for Disease Control and Prevention (CDC) and 35 partner organizations have engaged in developing an agenda for Preconception Health. A summit was held in June 2005 to discuss the current state of knowledge regarding preconception care and convene a select panel to develop recommendations and action steps for improving the health of women, children, and families through advances in clinical care, public health, and community action. A Select Panel on Preconception Care, convened by CDC, deliberated critical related issues and created refined definition of preconception care. The panel also developed a strategic plan with goals, recommendations, and action steps for improving preconception health. The recommendations and action steps are specific to the implementation of health behavior, access, consumer demand, research, and surveillance activities for monitoring and improving the health of women, children and families. The outcome of the deliberations is the CDC publication of detailed recommendations and action steps in the Morbidity and Mortality Weekly Report series, Recommendations and Reports.

  相似文献   
9.
MATTHEW  B.  COLLIER  C.  ANDERSON  ENGH  JR.  JAMES  P.  MCAULEY  STUART  D.  GINN  GERARD  A.  ENGH  蔡迅梓 《骨科动态》2006,2(2):93-99
背景:从关节和胫骨假体聚乙烯衬垫后表面转移磨损碎屑,是全膝关节置换术后假体周围骨溶解的主要原因。全膝人工关节假体设计随时问而发生变化,例如对胫骨盘近端表面的粗糙度和聚乙烯衬垫的灭菌方法。我们假设胫骨盘表面抛光和采用空气中γ射线照射之外的其他方法对衬垫灭菌,可降低骨溶解的发生率。方法:从1987年至1998年,我们采用后十字韧带保留型的解剖型组配式全膝人工关节假体系列。对300名患者施行365例全膝关节置换术。术后5至10年,对这些患者的膝关节摄正、侧位X线片。由两位关节置换专家对X线片上的骨溶解状况进行单独评定(骨溶解的界定标准为假体周围存在边缘清晰的非线性松质骨丢失区)。结果:在粗糙表面的胫骨盘的242例膝关节中,使用空气中γ射线照射灭菌的衬垫固定,有34%(82例)骨溶解阳性。用惰性气体中γ射线照射或没有照射的衬垫与抛光表面连接的98例膝关节中,有9%(9例)骨溶解阳性。骨溶解与六项因素相关,这些因素为:一项与患者(男性)相关、一项与胫骨盘(近端表面抛光)相关、三项与聚乙烯衬垫(加工的原材料、灭菌方法及存放时间)相关及一项与手术技术(股骨假体与胫骨假体间的过伸)相关。结论:在这类假体设计中,胫骨盘近端表面采用抛光及衬垫采用更为先进的灭菌方法(不用空气中γ射线照射灭菌)能显著减少骨溶解的发生率,但不能避免骨溶解。  相似文献   
10.
Parker  Lisa S. 《JAMA》1998,280(20):1798-1799
  相似文献   
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