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1.
Rian M. Hasson Kayla A. Fay Joseph D. Phillips Timothy M. Millington David J. Finley 《American journal of surgery》2021,221(4):725-730
BackgroundRural populations face many health disadvantages compared to urban areas. There is a critical need to better understand the current lung cancer screening landscape in these communities to identify targeted areas to improve the impact of this proven tool.MethodsData from the County Health Rankings of New Hampshire and Vermont was reviewed for population density, distribution of adult smokers, and level of education compared to the distribution of Lung Cancer Screening Facilities throughout these two states.ResultsScreening programs in southern counties of Vermont with lower levels of education have decreased access. In New Hampshire, there are no programs within 30 miles of the areas with the largest distribution of smokers, and decreased access in some areas with the lowest levels of education.ConclusionsImproving equitable access to high-quality screening services in rural regions and the creation of targeted interventions to address decreased access in areas of high tobacco use and low education is vital to decreasing the incidence of latestage presentations of lung cancer within these populations. 相似文献
2.
Dean Follmann Michael P Fay Toshimitsu Hamasaki Scott Evans 《Statistics in medicine》2020,39(5):602-616
Composite endpoints are frequently used in clinical trials, but simple approaches, such as the time to first event, do not reflect any ordering among the endpoints. However, some endpoints, such as mortality, are worse than others. A variety of procedures have been proposed to reflect the severity of the individual endpoints such as pairwise ranking approaches, the win ratio, and the desirability of outcome ranking. When patients have different lengths of follow-up, however, ranking can be difficult and proposed methods do not naturally lead to regression approaches and require specialized software. This paper defines an ordering score O to operationalize the patient ranking implied by hierarchical endpoints. We show how differential right censoring of follow-up corresponds to multiple interval censoring of the ordering score allowing standard software for survival models to be used to calculate the nonparametric maximum likelihood estimators (NPMLEs) of different measures. Additionally, if one assumes that the ordering score is transformable to an exponential random variable, a semiparametric regression is obtained, which is equivalent to the proportional hazards model subject to multiple interval censoring. Standard software can be used for estimation. We show that the NPMLE can be poorly behaved compared to the simple estimators in staggered entry trials. We also show that the semiparametric estimator can be more efficient than simple estimators and explore how standard Cox regression maneuvers can be used to assess model fit, allow for flexible generalizations, and assess interactions of covariates with treatment. We analyze a trial of short versus long-term antiplatelet therapy using our methods. 相似文献
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BCL2 protein signalling determines acute responses to neoadjuvant chemoradiotherapy in rectal cancer
5.
Patrick Niccola? Lemlih Ouchchane Maurice Libier Fay?ale Beouche Monique Belon Jean-Marc Vedrinne Bilal El Drayi Laurent Vallet Franck Ruiz Céline Biermann Pascal Duchêne Claudine Chirat Sylvie Soule-Sonneville Christian Dualé Claude Dubray Pierre Schoeffler 《Canadian journal of surgery》2015,58(2):114-120
Background
A greater incidence of persistent pain after inguinal herniorrhaphy is suspected with the open mesh procedure than with laparoscopy (transabdominal preperitoneal), but the involvement of neuropathy needs to be clarified.Methods
We examined the cumulative incidence of neuropathic persistent pain, defined as self-report of pain at the surgical site with neuropathic aspects, within 6 months after surgery in 2 prospective subcohorts of a multicentre study. We compared open mesh with laparoscopy using different analysis, including a propensity-matched analysis with the propensity score built from a multivariable analysis using a generalized linear model.Results
Considering the full patient sample (242 open mesh v. 126 laparoscopy), the raw odds ratio for neuropathic persistent pain after inguinal herniorrhaphy was 4.3. It reached 6.8 with the propensity-matched analysis conducted on pooled subgroups of 194 patients undergoing open mesh and 125 undergoing laparoscopy (95% confidence interval 1.5–30.4, p = 0.012). A risk factor analysis of these pooled subgroups revealed that history of peripheral neuropathy was an independent risk factor for persistent neuropathic pain, while older age was protective.Conclusion
We found a greater risk of persistent pain with open mesh than with laparoscopy that may be explained by direct or indirect lesion of nerve terminations. Strategies to identify and preserve nerve terminations with the open mesh procedure are needed. 相似文献6.
Fracture characteristics of carbon fibre, ceramic and non-palladium endodontic post systems at monotonously increasing loads 总被引:8,自引:0,他引:8
A carbon fibre post system, three non-palladium and one palladium metal post systems, two ceramic post systems, and a metal post system with a ceramic core were studied in vitro. The control group consisted of root-filled test teeth without posts. The test teeth were identical artificial roots of an upper central incisor made from a posterior composite whose module of elasticity was similar to that of natural dentine. All posts were cemented in the roots using Panavia 21 TC. Subsequently, standardized full crowns were cemented onto all roots. On a universal testing machine, the test teeth were loaded palatally at monotonously increasing loads until root fracture. The highest mean fracture loads were found for the carbon fibre post system (312.5 +/- 58.8 N). The fracture load of non-palladium metal posts (242.3-300.4 N) did not differ significantly from that of the Perma-dor post (265.9 N), which does contain palladium. Values of 300.3 +/- 89.3 N (aluminium oxide ceramics) and 193.5 +/-57.0 N (zirconia ceramics) were found for the ceramic posts. The control group exhibited a fracture load of 228.8 +/- 35.7 N. The mean distance between the vestibular end of the fracture gap and the point of force application was between 10.1 +/- 2.3 and 14.7 +/- 1.2 mm. 相似文献
7.
Gerald F. Williams RN RM Crit Care Cert BAppSc Grad Cert PSM MHA CN FRCNA Director of Nursing Services Fay J. Hatch RN RM RMHN Crit Care Cert BN Clinical Nurse Consultant Michael C. Bradley RN RMDN Crit Care Cert BN Registered Nurse 《Australian critical care》1997,10(4):113-118
Methanol intoxication, a rare and potentially lethal form of poisoning, usually results from ingestion and occasionally inhalation of methanol. Initial symptoms of blurred vision, elongated anion gap and metabolic acidosis are typically delayed and may not at first be recognised as methanol-related complaints. Once diagnosed, treatment must be prompt and definitive. As well as general supportive care, ethanol infusion, dialysis and alkalinization form the mainstays of treatment.
The cases described in this paper are compared to previous reports from other countries worldwide and contrast the variance in outcome often seen in methanol poisoning. The paper describes two tragic deaths and two lucky survivors, all of whom had consumed a cocktail of methanol and other alcoholic beverages at the same party.
The ICU nurse's role in managing the methanol-intoxicated patient relies on that person's sound knowledge of the unusual biochemical reactions occurring in the body and the need to institute definitive and supportive measures to help both patient and family recover. 相似文献
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Peroxisome proliferator-activated receptors (PPARs), members of the superfamily of nuclear steroid hormone receptors, have traditionally been studied for their role in lipid, glucose, and energy homeostasis. Recent evidence suggests that pharmacological activation of PPARgamma and PPARalpha, and inhibition of PPARdelta, may prevent cancer. PPARgamma agonists induce differentiation, inhibit the growth of established tumor cells in vitro and in vivo, and have chemopreventive effects in animal models. PPARalpha has anti-inflammatory and differentiating activity and protects against the oxidative damage associated with aging. In contrast, PPARdelta expression may be a factor in colorectal carcinogenesis. PPARdelta is normally repressed by the adenomatous polyposis coli tumor suppressor gene, and impaired adenomatous polyposis coli is strongly associated with human colorectal cancer risk. This review presents a rationale for using PPAR modulators as cancer chemopreventive drugs. 相似文献
10.
Expression of myogenic regulatory factors in chicken embryos during somite and limb development 下载免费PDF全文
The expression of the myogenic regulatory factors (MRFs), Myf5, MyoD, myogenin (Mgn) and MRF4 have been analysed during the development of chicken embryo somites and limbs. In somites, Myf5 is expressed first in somites and paraxial mesoderm at HH stage 9 followed by MyoD at HH stage 12, and Mgn and MRF4 at HH stage 14. In older somites, Myf5 and MyoD are also expressed in the ventrally extending myotome prior to Mgn and MRF4 expression. In limb muscles a similar temporal sequence is observed with Myf5 expression detected first in forelimbs at HH stage 22, MyoD at HH stage 23, Mgn at HH stage 24 and MRF4 at HH stage 30. This report describes the precise time of onset of expression of each MRF in somites and limbs during chicken embryo development, and provides a detailed comparative timeline of MRF expression in different embryonic muscle groups. 相似文献