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41.
The present paper presents a new method for generating ultrasound, based on the interaction of laser-induced ultrasound generation and ultrasonic holography. An ultrasonic field generated in a water tank via the optoacoustic effect is spatially and temporally controlled: In order to produce defined ultrasonic frequencies in the MHz range, the laser pulses incident on a light-absorbing layer are modulated in time using an electro-optic modulator (EOM). Additionally, a high-resolution liquid crystal spatial light modulator (SLM) is used to imprint a pre-calculated phase front to the laser beam. A computer-generated binary hologram is also displayed at the SLM. The expanded laser beam projects the corresponding pattern to the plane absorptive layer in the water tank. The projection of specific patterns for the generation of ultrasonic beams resembles the use of, diffractive optical elements" in optics. Optical ultrasound generation with holographic steering is a flexible tool with promising numerous new applications in medical and technical ultrasound diagnostics.  相似文献   
42.
Dissimulation is the concealment of genuine psychiatric symptoms in an attempt to present a picture of psychiatric health. In this pilot study, the authors set out to demonstrate that defendants may conceal psychiatric illness even in forensic settings, contrary to their apparent self-interest. They reviewed their records for forensic assessments of dissimulators and malingerers and classified dissimulators as "intentional" or "uninsightful" depending on whether their concealment of symptoms appeared to be a volitional act or driven by a lack of insight. Although there were obvious diagnostic differences, the only other significant difference between malingerers and dissimulators was that malingerers were more likely to be facing charges related to financial crimes. Uninsightful dissimulators were significantly older than were intentional dissimulators. Uninsightful dissimulators were also more likely to be psychotic, particularly delusional and schizophrenic, than were intentional dissimulators. While forensic psychiatrists are vigilant in attempts to detect malingering, these data suggest that they should be equally vigilant regarding the possibility of dissimulation. Although further study is indicated, it appears that dissimulators are a heterogeneous group.  相似文献   
43.
There is evidence that the motor cortex is involved in cardiovascular adjustments associated with somatic motor activity, as it has functional connections with the ventrolateral medulla, a brainstem region critically involved in the control of blood pressure and the regulation of plasma catecholamine levels. The ventrolateral medulla sends projections to the spinal intermediolateral nucleus, where preganglionic neurones controlling heart and blood vessels (T2 segment) and adrenal medulla (T8 segment) are found. The aim of the present study was to determine whether electrical stimulation of the rat motor cortex induces cardiovascular responses and Fos expression in ventrolateral medulla neurones projecting to the T2 and T8 segments. After a set of experiments designed to record cardiovascular parameters (blood pressure and plasma catecholamine levels), injections of retrograde tracer (Fluorogold) were performed in the intermediolateral nucleus of two groups of rats, at the T2 or at the T8 segmental levels. Five days later, the motor cortex was stimulated in order to induce Fos expression in the ventrolateral medulla. Stimulation of the motor cortex induced: (1). hypotension and a significant decrease in plasma noradrenaline levels, and (2). a significant increase in the number of the double-labelled neurones in the rostral ventrolateral medulla projecting to T2. These data demonstrate that cardiovascular adjustments, preparatory to, or concomitant with, motor activity may be initiated in the motor cortex and transmitted to cardiac and vasomotor spinal preganglionic neurones, via the ventrolateral medulla.  相似文献   
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Local public health agencies are funded federal, state, and local revenue sources. There is a common belief that increases from one source will be offset by decreases in others, as when a local agency might decide it must increase taxes in response to lowered federal or state funding. This study tests this belief through a cross-sectional study using data from Missouri local public health agencies, and finds, instead, that money begets money. Local agencies that receive more from federal and state sources also raise more at the local level. Given the particular effectiveness of local funding in improving agency performance, these findings that nonlocal revenues are amplified at the local level, help make the case for higher public health funding from federal and state levels.  相似文献   
46.
Introduction: Adverse drug reactions (ADRs) are an important cause of morbidity and mortality worldwide. They are associated with healthcare costs due to hospital admissions or prolonged length of stay, as well as additional interventions. The aim of this study was to conduct a systematic review of observational studies to evaluate the economic impact of preventable ADRs.

Areas covered: Published observational research investigating the cost of preventable ADRs in Western countries (limited to the USA and European countries).

Expert opinion: Several reviews have been carried out in the field of the ADR epidemiology but fewer reviews have investigated the economic impact of ADRs, and at the time of writing, none has focused on preventable ADRs. The reason why future research should focus on the costs of preventable ADRs is that both the costs and the negative clinical outcomes are preventable, and as such, are a key point of public health policy action. Nevertheless, the present review highlights an important and sobering limitation of published research on the cost of preventable ADRs, of which the major limitation is the heterogeneity in methods and in reporting which limit what can be known through the summarizing work of a systematic review.  相似文献   

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The main source of capital for non-for-profit health care organizations is tax-exempt municipal bonds. The tax-exempt nature of this debt requires that they be issued through financing authorities, which are run by, or affiliated with, state or local government agencies. In some states, all tax-exempt health care bonds must be issued through a single financing authority, but in other states the issuing health care organization has a choice of multiple authorities. Using a Herfindahl index of issuer concentration, prior research has found that greater competition among authorities results in lower interest costs to the issuing health care organization. We pick up where this earlier study left off, examining the links between authority competition, the interest expenses to the issuer, and the yield to the market investor. Although our analysis of all hospital bonds issued between 1994 and 2002 corroborates earlier findings with regard to interest expenses to the issuing health care organization, we also find market yield is lower for statewide authorities where issuer concentration is lower. Thus, authority competition is good from the issuers' point of view, but holds no favor in the investors' eyes. On the other hand, the lower market yield associated with statewide authorities does not make its way down to the issuer in the form of lower interest costs. To help sort through this paradox, we explore our findings through interviews of executives in state issuing authorities.  相似文献   
49.
The retina, like many cancers, produces energy from glycolysis even in the presence of oxygen. This phenomenon is known as aerobic glycolysis and eponymously as the Warburg effect. In recent years, the Warburg effect has become an explosive area of study within the cancer research community. The expanding knowledge about the molecular mechanisms underpinning the Warburg effect in cancer promises to provide a greater understanding of mammalian retinal metabolism and has motivated cancer researchers to target the Warburg effect as a novel treatment strategy for cancer. However, if the molecular mechanisms underlying the Warburg effect are shared by the retina and cancer, treatments targeting the Warburg effect may have serious adverse effects on retinal metabolism. Herein, we provide an updated understanding of the Warburg effect in mammalian retina.  相似文献   
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