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91.
This paper propose a universal normalized vegetation index (UNVI), which is an improved vegetation index (VI) based on the universal pattern decomposition method (UPDM), termed VIUPD. We also derive new matrices to facilitate convenient calculation of the UNVI based on data from the MODIS and Landsat-TM, ETM, OLI satellite sensors. We compared the performance of the UNVI to the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) and modified soil adjusted vegetation index 2 (MSAVI2) to estimate the vegetation dynamics (chlorophyll content and leaf area index [LAI]). The results show that the UNVI was more sensitive to vegetation dynamics than the NDVI, EVI and MSAVI2. The UNVI has a higher LAI saturation point than the other three indices. The UNVI can be used to monitor global changes in above ground biomass (AGB) and gross primary production (GPP) with respect to a wide range of vegetation dynamics.  相似文献   
92.

Background

Although it is known that women do not participate in trials as frequently as men, there are limited recent data examining how women recruitment has changed over time.

Methods

We conducted MEDLINE search using a validated strategy for randomized trials published in New England Journal of Medicine, Lancet, and Journal of the American Medical Association between 1986 and 2015, and included trials evaluating pharmacologic or nonpharmacologic therapies. We abstracted data on demographics, intervention type, clinical indication, and trial design characteristics, and examined their relationships with women enrollment.

Results

In total, 598 trials met inclusion criteria. Women enrollment increased significantly over time (21% between 1986 and 1990 to 33% between 2011 and 2015; Pfor trend < 0.001) and did not differ by journal or funding source. Women enrollment varied with clinical indication, comprising 37% for non–coronary artery disease vascular trials, 30% for coronary artery disease trials, 28% for heart failure trials, and 28% for arrhythmia trials (P < 0.001), which were all significantly lower than the expected proportion in disease populations (P < 0.001). Women enrollment varied with trial type (31%, 29%, and 26% for pharmacologic, device, and procedural trials, respectively; P = 0.001). These findings were corroborated using multivariable analysis. We found significant positive correlations between women enrolled, and mean age and total number of participants. Fewer women were enrolled in trials reporting statistically significant results than those who did not (P = 0.001).

Conclusions

Although enrollment of women has increased over time, it remains lower than the relative proportion in the disease population. Future studies should elucidate the reasons for persistent under-representation of women in clinical trials.  相似文献   
93.
Weltweit entstehen an Feiertagen schwere Augenverletzungen durch Feuerwerkskörper. Die Datenlage für Deutschland ist bislang unklar. Wie häufig entstehen solche Verletzungen in Deutschland, wer ist gefährdet, wie schwer sind die Verletzungen, welche Therapien erfordern sie, und wie häufig treten Begleitverletzungen auf? Deutschlandweite standardisierte Online-Umfrage an bettenführenden, notdienstleistenden Augenkliniken und Auswertung der Ergebnisse über 3 Jahre. Die Beteiligung konnte von 2016 bis 2019 von 41 auf 51 Augenkliniken gesteigert werden. Von 1356 Patienten war mehr als ein Drittel (33–39 %) minderjährig, rund 60 % 25 Jahre oder jünger und rund 60 % Bystander. Ein Viertel der Verletzungen war schwer und erforderte eine stationäre Therapie. Begleitverletzungen am Partnerauge, an Händen und Gesicht waren bei Minderjährigen häufiger als bei Erwachsenen. Bulbusrupturen wurden bei 10 Kindern und 38 Erwachsenen dokumentiert. Vor allem Minderjährige und Zuschauer müssen besser geschützt werden.  相似文献   
94.
In an article in this issue of the Hastings Center Report, Aaron Wightman and his coauthors attempt to address health care providers’ moral distress about acceding to parents’ requests to provide life‐sustaining medical treatment to children who have profound cognitive disabilities. They propose combining John Arras's relational potential standard and care ethics, and they argue that the capacity for caring relationships can provide an independent moral justification for honoring such requests. This combination is, however, unstable. Wightman et al.'s language of potential and capacity opens the possibility of substantial misinterpretation. They rely on epistemological and prognostic uncertainty to argue that reciprocity and participation may be present in the parent‐child relationship even when the child's engagement cannot be observed. The terminology suggests that these are characteristics that can be gained or lost rather than characteristics of being born within certain social practices. In contrast, Eva Feder Kittay illuminates family membership as an important social relation. Her articulation of the independent moral value of parenting stands on its own without being conjoined to Arras's position.  相似文献   
95.
Bulletin of Environmental Contamination and Toxicology - This work describes the development of an analytical protocol combining cleanup by liquid–solid extraction and GC–MS for the...  相似文献   
96.

Objectives

The aim of this study was to develop a high-fidelity minimally invasive mitral valve surgery (MIMVS) simulator.

Methods

The process of industrial serial design was applied based on pre-set requirements, acquired by interviewing experienced mitral surgeons. A thoracic torso with endoscopic and robotic access and disposable silicone mitral valve apparatus with a feedback system was developed. The feedback system was based on 4 cameras around the silicone valve and an edge detection algorithm to calculate suture depth and width. Validity of simulator measurements was assessed by comparing simulator-generated values with measurements done manually on 3-dimensional reconstructed micro-computed tomography scan of the same sutures. Independent surgeons tested the simulator between 2014 and 2018, whereupon an evaluation was done through a questionnaire.

Results

The feedback system was able to provide width and depth measurements, which were subsequently scored by comparison to pre-set target values. Depth did not significantly differ between simulator and micro-computed tomography scan measurements (P = .139). Width differed significantly (P = .001), whereupon a significant regression equation was found (P < .0001) to calibrate the simulator. After calibration, no significant difference was found (P = .865). In total, 99 surgeons tested the simulator and more than agreed with the statements that the simulator is a good method for training MIMVS, and that the mitral valve and suture placement looked and felt realistic.

Conclusions

We successfully developed a high-fidelity MIMVS simulator for endoscopic and robotic approaches. The simulator provides a platform to train skills in an objective and reproducible manner. Future studies are needed to provide evidence for its application in training surgeons.  相似文献   
97.

Background

Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.

Methods

A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.

Results

Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.

Conclusion

Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile.  相似文献   
98.
99.
This review forms part of a series of annual updates that summarize the evidence base for atopic eczema (AE). It provides a summary of key findings from 25 systematic reviews that were published or indexed during 2017, and focuses on the treatment and prevention of AE. There is high‐quality evidence to demonstrate that dupilumab is better than placebo for the treatment of AE, is not associated with a higher incidence of adverse effects and does not increase the risk of infection compared with placebo; however, comparison studies with other systemic treatments are necessary. Topical tofacitinib is a promising treatment for mild–moderate AE, but currently lacks sufficient evidence from well‐designed randomized controlled trials (RCTs) comparing with other active treatments. Topical doxepin may be effective for pruritus in AE, but available studies have short follow‐up periods and longer‐term outcomes are needed. Bleach baths were no more effective than water baths alone at reducing AE severity. Topical antibiotics cannot be recommended for infected AE, owing to insufficient evidence of benefit. There is little comparison of different emollients in RCTs, but overall evidence indicates that they reduce AE severity, are steroid‐sparing and lead to better outcomes in combination with topical corticosteroids (TCS) than TCS alone. No clear benefit was demonstrated for vitamin D/C/E supplementation in pregnancy for eczema prevention.  相似文献   
100.

Objectives

Studies have shown that having a baseline mammogram, the first screening mammogram, available for comparison at the time of interpreting a subsequent mammogram significantly decreases the potential of a false-positive examination. Our aim was to evaluate knowledge of and perception about the significance of baseline mammograms in those women undergoing screening mammography.

Materials and Methods

A cross-sectional prospective survey study was conducted in women without a history of breast cancer presenting for their screening mammogram. Respondents were surveyed anonymously between March and April 2017. The questionnaire was developed by primary care providers and radiologists and pretested for readability and clarity.

Results

In all, 401 women (87% white, 93% educated beyond high school) completed surveys in which 77% of women reported having yearly mammograms, 31% reported having a history of an abnormal mammogram, and 45% had not heard the term baseline mammogram. Of those who had heard the term, the most commonly reported source was their primary care provider (31%). Although 74% chose the correct definition of a baseline mammogram, 67% did not think that a baseline mammogram was important for decreasing associated cost, time, and discomfort due to the number of mammograms incorrectly read as abnormal.

Conclusion

In a group of educated women who routinely get mammograms, almost one-half had not heard the term baseline mammogram. Furthermore, most women did not think baseline mammography was important for decreasing associated cost, time, and discomfort due to mammograms incorrectly read as abnormal. This study suggests that efforts to improve women’s understanding of baseline mammograms and their importance are warranted, with greatest opportunity for health care providers and radiologists.  相似文献   
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