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Grippo JO 《Journal of the American Dental Association (1939)》2007,138(12):1535; author reply 1535-1535; author reply 1536
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This study investigated the potential of pooled milk as an alternative sample type for foot‐and‐mouth disease (FMD) surveillance. Real‐time RT‐PCR (rRT‐PCR) results of pooled milk samples collected weekly from five pooling facilities in Nakuru County, Kenya, were compared with half‐month reports of household‐level incidence of FMD. These periodic cross‐sectional surveys of smallholder farmers were powered to detect a threshold household‐level FMD incidence of 2.5% and collected information on trends in milk production and sales. FMD virus (FMDV) RNA was detected in 9/219 milk samples, and using a type‐specific rRT‐PCR, serotype SAT 1 was identified in 3/9 of these positive samples, concurrent with confirmed outbreaks in the study area. Four milk samples were FMDV RNA‐positive during the half‐months when at least one farmer reported FMD; that is, the household‐level clinical incidence was above a threshold of 2.5%. Additionally, some milk samples were FMDV RNA‐positive when there were no reports of FMD by farmers. These results indicate that the pooled milk surveillance system can detect FMD household‐level incidence at a 2.5% threshold when up to 26% of farmers contributed milk to pooling facilities, but perhaps even at lower levels of infection (i.e., below 2.5%), or when conventional disease reporting systems fail. Further studies are required to establish a more precise correlation with estimates of household‐level clinical incidence, to fully evaluate the reliability of this approach. However, this pilot study highlights the potential use of this non‐invasive, routinely collected, cost‐effective surveillance tool, to address some of the existing limitations of traditional surveillance methods.  相似文献   
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Three patients complained of spontaneous and exertional chest pain, both associated with S-T segment depression in anterior electrocardiographic leads. In each, coronary spasm was demonstrated on coronary arteriography during a spontaneous attack of pain. Coronary arteriograms taken during exercise-induced angina did not show evidence of spastic obstruction; this suggests that exercise-induced chest pain and S-T segment depression were secondary to the increase in oxygen requirements rather than to a sudden decrease in coronary blood flow. Thus, two pathogenetic mechanisms coexisting in the same patient may cause chest pain associated with subendocardial ischemia.  相似文献   
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Background

Intravascular volume expansion plays a major role in the prevention of contrast-induced acute kidney injury (CI-AKI). Recommended standard amounts of fluid infusion before procedures do not produce homogeneous responses in subjects with different initial hydration status.

Objectives

The goal of this study was to compare the effect of standard and double intravenous (IV) infusion volumes in patients with low body fluid level, assessed by using bioimpedance vector analysis (BIVA), on the incidence of CI-AKI after elective coronary angiographic procedures.

Methods

A total of 303 patients with low BIVA level on admission were randomized to receive standard volume saline (1 ml/kg/h for 12 h before and after the procedure) or double volume saline (2 ml/kg/h). Patients (n = 715) with an optimal BIVA level received standard volume saline and were included in a prospective registry. The saline infusion was halved in all patients with an ejection fraction <40%. BIVA was repeated immediately before the angiographic procedure in all patients. CI-AKI was defined as an increase in levels of cystatin C ≥10% above baseline at 24 h after contrast administration.

Results

The incidence of CI-AKI was significantly lower (11.5% vs. 22.3%; p = 0.015) in patients receiving double volume saline than in those receiving standard volume saline, respectively. Before the angiographic procedure, 50% of the double volume patients achieved the optimal BIVA level compared with only 27.7% in the standard group (p = 0.0001). The findings were consistent in all the pre-specified subgroups excluding patients with a left ventricular ejection fraction <40% (p for interaction = 0.01).

Conclusions

Evaluation of BIVA levels on admission in patients with stable coronary artery disease allows adjustment of intravascular volume expansion, resulting in lower CI-AKI occurrence after angiographic procedures. (Personalized Versus Standard Hydration for Prevention of CI-AKI: A Randomized Trial With Bioimpedance Analysis; NCT02225431)  相似文献   
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The integrated clinical, laboratory and ultrasound approach is essential for the diagnosis, evaluation and monitoring of the patient's therapy in coronavirus disease 2019 pneumonia. The ideal imaging approach in this context is not yet well defined. Chest X-ray is characterized by low sensitivity in identifying earlier lung changes. The "bedside" pulmonary ultrasound has an undeniable series of advantages in the patient at high infectious risk and can provide incremental data in the respiratory intensive care for the serial control of the individual patient as well as for the home delivery of the stabilized subjects. Pulmonary computed tomography shows high sensitivity but should not be routinely performed in all patients, because in the first 48 h it can be absolutely negative and in the late phase the imaging findings may not change the therapeutic approach. Echocardiography should be limited to patients with hemodynamic instability to assess ventricular function and pulmonary pressures.  相似文献   
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The present work aimed to investigate the dry sliding wear behaviors of hybrid polymer matrix composites made up of Kevlar, bamboo, palm, and Aloe vera as reinforcement materials of varying stacking sequences, along with epoxy as the matrix material. Three combinations of composite laminates with different stacking sequences such as AB, BC, and CA were fabricated by a vacuum-assisted compression molding process. The influence of composite laminates fabricated through various stacking sequences and dry sliding wear test variables such as load, sliding distance, and sliding velocity on the specific wear rate and co-efficient of friction were investigated. Experiments were designed and statistical validation was performed through response surface methodology-based D-optimal design and analysis of variance. The optimization was performed using grey relational analysis (GRA) to identify the optimal parameters to enhance the wear resistance of hybrid polymer composites under dry sliding conditions. The optimal parameters, such as composite combinations of CA, a load of 5 N, a sliding velocity of 3 m/s, and a sliding distance of 1500 m, were obtained. Furthermore, the morphologies of worn-out surfaces were investigated using SEM analysis.  相似文献   
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