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A huge number of risk assessment tools have been developed. Far from all have been validated in external studies, more of them have absence of methodological and transparent evidence, and few are integrated in national guidelines. Therefore, we performed a systematic review to provide an overview of existing valid and reliable risk assessment tools for prediction of osteoporotic fractures. Additionally, we aimed to determine if the performance of each tool was sufficient for practical use, and last, to examine whether the complexity of the tools influenced their discriminative power. We searched PubMed, Embase, and Cochrane databases for papers and evaluated these with respect to methodological quality using the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS) checklist. A total of 48 tools were identified; 20 had been externally validated, however, only six tools had been tested more than once in a population‐based setting with acceptable methodological quality. None of the tools performed consistently better than the others and simple tools (i.e., the Osteoporosis Self‐assessment Tool [OST], Osteoporosis Risk Assessment Instrument [ORAI], and Garvan Fracture Risk Calculator [Garvan]) often did as well or better than more complex tools (i.e., Simple Calculated Risk Estimation Score [SCORE], WHO Fracture Risk Assessment Tool [FRAX], and Qfracture). No studies determined the effectiveness of tools in selecting patients for therapy and thus improving fracture outcomes. High‐quality studies in randomized design with population‐based cohorts with different case mixes are needed.  相似文献   
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Treatment of patients with concurrent mental illness and substance abuse represents a challenge to the traditional treatment systems. This article gives: 1) an introduction of the concept and frequency of dual diagnosis (DD), 2) a presentation and discussion of the latest guidelines on DD treatment, 3) status on the current situation in the DD field in Denmark, and 4) potentials for future research. The article is based on systematic examination of evidence-based research and popularized latest guidelines on DD treatment. Methodologically, both treatment and research is challenged by the diversity in DD combinations. Although integrated treatment with the inclusion of cognitive–behavioural therapy, motivational interviewing and family intervention in DD treatment show promising results, it remains to establish which treatment programme is the most qualified in improving mental health and reducing substance use. A future priority is the development of DD treatment that targets specific co-morbid combinations and treatment needs.  相似文献   
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We investigated whether a novel visitation model for school-aged youth with mental health problems based on a stage-based stepped-care approach facilitated a systematic identification and stratification process without problems with equity in access. The visitation model was developed within the context of evaluating a new transdiagnostic early treatment for youth with anxiety, depressive symptoms, and/or behavioural problems. The model aimed to identify youth with mental health problems requiring an intervention, and to stratify the youth into three groups with increasing severity of problems. This was accomplished using a two-phase stratification process involving a web-based assessment and a semi-structured psychopathological interview of the youth and parents. To assess problems with inequity in access, individual-level socioeconomic data were obtained from national registers with data on both the youth participating in the visitation and the background population. Altogether, 573 youth and their parents took part in the visitation process. Seventy-five (13%) youth had mental health problems below the intervention threshold, 396 (69%) were deemed eligible for the early treatment, and 52 (9%) had symptoms of severe mental health problems. Fifty (9%) youth were excluded for other reasons. Eighty percent of the 396 youth eligible for early treatment fulfilled criteria of a mental disorder. The severity of mental health problems highlights the urgent need for a systematic approach. Potential problems in reaching youth of less resourceful parents, and older youth were identified. These findings can help ensure that actions are taken to avoid equity problems in future mental health care implementations.

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Previously we have investigated a depth-independent compensation for collimator detector response (CDR) included in the OSEM reconstruction, intended for SPECT images that have been corrected for scatter and septal penetration using convolution-based methods. In this work, the aim was to study how different filtering strategies affect contrast as a function of noise when using Gaussian smoothing filters in combination with the above-described CDR compensation. The evaluation was performed for (123)I dopamine transporter (DAT) SPECT images. Prefiltering with 2D Gaussian filter kernels, where the deterioration in resolution is included in the depth-independent CDR compensation, was compared to conventional postfiltering with 3D Gaussian filter kernels. Images reconstructed without filtering are also included in the comparison. It was found that there is little benefit in noise reduction when using CDR compensation. However, this variant of prefiltering gives consistently higher contrasts as a function of noise compared with the postfiltering alternative, and that could be of interest when using other types of filters with contrast improving properties.  相似文献   
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Purpose

To examine whether maternal fever during pregnancy is associated with reduced head circumference and risk of microcephaly at birth.

Methods

A prospective study of 86,980 live-born singletons within the Danish National Birth Cohort was carried out. Self-reported maternal fever exposure was ascertained in two interviews during pregnancy and information on head circumference at birth was extracted from the Danish Medical Birth Registry.

Results

Fever in pregnancy was reported by 27% of the mothers, and we identified 3370 cases of microcephaly (head circumference less than or equal to third percentile for sex and gestational age) and 1140 cases of severe microcephaly (head circumference less than or equal to first percentile for sex and gestational age). In this study, maternal fever exposure was not associated with reduced head circumference (adjusted β = 0.03, 95% confidence intervals [CI]: 0.01–0.05), increased risk of microcephaly (odds ratio: 0.95, 95% CI: 0.88–1.03) nor severe microcephaly (odds ratio: 1.01, 95% CI: 0.88–1.15) in the offspring. These findings were consistent for increasing numbers of fever episodes, for increasing fever severity, and for exposure in both early pregnancy and midpregnancy.

Conclusions

In this most comprehensive study to date, we found no indication that maternal fever in pregnancy is associated with small head size in the offspring.  相似文献   
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BACKGROUND/AIMS: We investigated whether increasing the efferent vagal activity by insulin-induced hypoglycemia would enhance gastric emptying and volumes in healthy subjects. METHODS: Twenty healthy volunteers (10 males) were examined with and without vagal stimulation by insulin-induced hypoglycemia using a glucose clamp technique. Stomach function was tested by drinking meat soup (0.04 kcal ml(-1)) at a rate of 100 ml min(-1) until maximal capacity. Intragastric volume at maximal drinking capacity was determined by three-dimensional ultrasound. Respiratory sinus arrhythmia (RSA) was used as an index of cardiac vagal activity and plasma pancreatic polypeptide (PP) as a measure of gastric vagal activity, and skin conductance (SC) as a measure of sympathetic tone. RESULTS: Insulin-induced hypoglycaemia increased drinking capacity (p = 0.002), gastric emptying (p = 0.02), PP (p = 0.004) and SC (p = 0.004), while intragastric volume was unchanged (p = 0.7) and RSA decreased (p = 0.03). CONCLUSION: Enhancement of gastric vagal activity by insulin-induced hypoglycemia increased drinking capacity and gastric emptying similarly, resulting in an unchanged intragastric volume. Enhanced efferent vagal activity to the stomach (as measured by PP) was not associated by enhanced cardiac vagal activity (as measured by RSA), possibly a consequence of stress-induced sympathetic activation during the procedure.  相似文献   
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D1 and D2 dopamine receptors (D1DRs and D2DRs) may contribute differently to various aspects of memory and cognition. The D1DR system has been linked to functions supported by the prefrontal cortex. By contrast, the role of the D2DR system is less clear, although it has been hypothesized that D2DRs make a specific contribution to hippocampus-based cognitive functions. Here we present results from 181 healthy adults between 64 and 68 y of age who underwent comprehensive assessment of episodic memory, working memory, and processing speed, along with MRI and D2DR assessment with [11C]raclopride and PET. Caudate D2DR availability was positively associated with episodic memory but not with working memory or speed. Whole-brain analyses further revealed a relation between hippocampal D2DR availability and episodic memory. Hippocampal and caudate D2DR availability were interrelated, and functional MRI-based resting-state functional connectivity between the ventral caudate and medial temporal cortex increased as a function of caudate D2DR availability. Collectively, these findings indicate that D2DRs make a specific contribution to hippocampus-based cognition by influencing striatal and hippocampal regions, and their interactions.Dopamine (DA) plays a key role in several cognitive processes (14). Reductions of D1 and D2 DA receptors (D1DRs and D2DRs) in aging (57) have been linked to age-related cognitive deficits (8, 9). The D1DR system has been related to functions supported by the prefrontal cortex (PFC), such as working memory and executive functions (1012), which may reflect the relatively high density of D1DRs in the PFC (13). However, the role of D2DRs is far less clear. D2DRs are present in the PFC at very low densities (13), and evidence supporting a role for the D2DR system in working memory and executive functions is elusive (10). Pharmacological (14, 15) and PET studies assessing striatal D2DR availability (or binding potential to nondisplacable tissue uptake; BPND) with [11C]raclopride (16, 17) have yielded mixed findings in relation to cognition. It has been hypothesized that D2DRs make a specific contribution to hippocampus-based cognitive functions (10, 18, 19). Supporting these claims, positive links between D2DR BPND and episodic memory are commonly observed (2023). PET imaging of hippocampal D2DR BPND also provides support for this hypothesis, although some studies indicate that hippocampal D2DRs may be related to both episodic memory and PFC-based executive functions (22, 23), including verbal working memory (24). Medial temporal lobe regions have been implicated in working memory (25, 26), and D2DR-mediated modulation may be exerted via hippocampal–cortical pathways (27). In addition, a [11C]raclopride task-activation PET study demonstrated contributions of striatal D2DRs to a verbal working-memory task (11).Taken together, the specific role of the D2DR system in cognition remains unclear, likely due to the fact that past studies included small and age-heterogeneous samples and lacked comprehensive test batteries that allowed systematic comparison of the role of D2DRs in different cognitive functions. Here we present results from the Cognition, Brain, and Aging (COBRA) study that include assessment of episodic memory, working memory, and processing speed, in combination with [11C]raclopride PET and MRI of 181 healthy adults between 64 and 68 y of age (28). The main analyses concerned caudate D2DR–cognition associations, as this striatal region has been implicated in cognitive functioning (11, 12, 29, 30). Subsequently, whole-brain analyses were conducted to examine extrastriatal (especially hippocampal) D2DRs in relation to cognition. Finally, resting-state functional connectivity patterns were analyzed in relation to D2DR BPND, with special focus on interactions between the ventral caudate (31) and medial temporal cortex regions (32, 33).  相似文献   
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