BACKGROUND: Several studies have demonstrated that transient self-induced sadness activates anterior paralimbic structures. To further examine the specificity of these findings and the neural substrates involved in anger and anxiety, we studied the neural correlates of the induction of anxiety and anger in healthy adults. METHODS: We used H2(15)O and positron emission tomography (PET) to measure regional cerebral blood flow (rCBF) in 16 healthy adults during the induction of transient anxiety, anger, and neutral emotions. Subjects achieved differential emotions by recalling prior life events while viewing affect-appropriate faces. RESULTS: Both the anxiety and anger conditions were associated with increased normalized rCBF in left inferior frontal and left temporal pole regions and decreased rCBF in right posterior temporal/parietal and right superior frontal cortex, compared to the neutral induction. Additionally, compared to neutral induction, anxiety was associated with increased rCBF in the left anterior cingulate and cuneus and decreased rCBF in right medial frontal cortex, while the anger induction was uniquely associated with increased rCBF in right temporal pole and thalamus. CONCLUSIONS: Self-generated transient states of anxiety and anger are associated with both overlapping and distinct regional brain activity patterns and provide a template for further dissection of specific components of normal and pathologic emotions. 相似文献
OBJECTIVE: To assess the influence of the display monitor on observer performance. MATERIAL AND METHODS: Artificial enamel lesions were created in 40 extracted teeth at random using 1/4 and 1/2 round burs. Teeth were mounted in dental stone blocks to simulate a hemidentition. Approximate exposures were recorded at 70 kVp using a Digota (Soredex, Orion Corp, Helsinki, Finland) digital imaging system, calibrated to achieve optimum density. Six dentists rated each image on a five-point scale for the presence or absence of a lesion. Radiographic images were viewed on the following monitors: (1) AlphaScan 711 (Sampo Corp.); (2) Multiscan 17 Se II (Sony Electronics Inc.); (3) DS 2000 (Clinton Electronics Corp.) and (4) Latitude CP Laptop (Dell Computer Corp.). Raters were allowed to magnify and to adjust density and contrast of each image at will. Receiver Operating Characteristic (ROC) analysis was performed and curves were plotted for each image. Data was subjected to repeated measures analysis of variance and ordinal logistic regression to test for significance between variables and to determine odds ratios. RESULTS: Mean ROC curve areas ranged from 0.8728 for the Sampo monitor to 0.8395 for the Sony. Repeated measures analysis of variance showed significant differences between observers (P < 0.0001), lesion size (P < 0.0001), examiner/monitor interaction (P < 0.033) and examiner/block interaction (P < 0.013). However, no significant difference was found between monitors. CONCLUSION: This study suggests that observer performance is independent of the visual characteristics of the display monitor. 相似文献
There is a long-standing recognition that there is an organ donor shortage in the United Kingdom and Ireland (UK&E) that limits transplant activity. However, the fact that, at present, there are several unfilled consultant vacancies would suggest that a shortage of trained surgeons may soon be an equally important limiting factor. The aim of this current study was to identify all transplant trainees in the UK&E and to determine their career aspirations. A list of all trainees intending to practice as transplant surgeons was compiled. A combination of postal questionnaire and telephone interview was used to construct a database on past and present training in transplantation, and preferred type of consultancy was assessed both by direct questioning and by using a visual analogue scale to grade desirability of various posts. Of 110 potential trainees identified, 50 (45%) replied and indicated a desire to pursue a career in transplant surgery. Thirty-one intended practising in the UK&E (19 UK&E graduates and 12 overseas). The preferred consultancy (27/31) was transplantation (Tx) together with a second specialty while only four wanted a multivisceral practice. The mean score (0-10) for desirability of a multivisceral transplant post was 4.7, for renal transplant and vascular access it was 3.6 and for transplantation and a second specialty it was 8.4. We conclude that the majority of trainees do not wish to apply for pure transplant posts, either single organ or multivisceral, and that the majority wish to practice transplantation with a second specialty. In addition, there is still a major shortage of trainees and further studies are required to identify reasons why trainees fail to pursue a career in transplantation. 相似文献
This report describes a case of 16 small bowel atresias in a twin who was born at 31 weeks' gestation, weighing 1,690 g. All atresias and intestinal segments of 5 cm or less in length were resected, resulting in nine primary anastomoses, preserving 75% (107 cm) of his initial small bowel length. The baby went home on full oral feedings after 10 weeks. Multiple anastomoses in the low-birth-weight neonate can be tolerated with the functional benefit of maximal bowel length. The time taken to tolerate feedings appears to be independent of the number of anastomoses. Vascular anastomoses associated with monochorionic twinning may place both fetuses at risk of intestinal atresia in the event of an ischemic insult, either concurrently or with the demise of one affecting the other. Prenatal ultrasound scan appears to be useful for monitoring the evolution of intestinal atresia. However, the risks of extreme prematurity preclude the delivery of the affected baby at the time of initial diagnosis, and as yet it is unknown whether early delivery will alter the number, type, or prognosis of multiple atresias. 相似文献
Objectives. We sought to determine clinical, angiographic, and echocardiographic predictors of survival in children with isolated hypertrophic cardiomyopathy (HCM) in a large pediatric centre.
Background. Sudden death is a catastrophic outcome of HCM in childhood but has been difficult to predict. Current therapies might provide for improved outcome if factors identifying high risk can be identified.
Methods. Records of 99 patients diagnosed with HCM from 1958 to 1997 at <18 yr were reviewed for clinical, angiographic (n = 62) and echocardiographic (n = 83) predictors of survival outcome. The effects of clinical characteristics on sudden death (including resuscitated sudden death) were individually tested in Cox’s proportionate hazard modeling.
Results. Seventy-one subjects were male. Median age at diagnosis was 5.0 yr with a medical follow-up interval of 4.8 yr. Thirty-seven of 97 patients had a family history of HCM. Ambulatory electrocardiograms (ECG) in 78 patients demonstrated supraventricular tachycardia in 16 and ventricular tachycardia in 21. Death or resuscitated sudden death occurred in 18 patients. Sudden death rate was 2.7%/yr after age 8 yr. Cox’s proportionate survival modeling revealed increased corrected QT interval (QTc) dispersion on ECG (relative risk [RR] 1.61 per 20 ms increment, p < 0.0003), ventricular tachycardia (VT) on ambulatory ECG (RR 3.75, p < 0.006) and myocardial bridging of the LAD coronary (RR 12.0, p < 0.003) to be associated with reduced time to death or resuscitated sudden death.
Conclusions. Detailed assessment of ECGs, ambulatory ECGs, and coronary angiography can assist in identifying which children with HCM are at risk for sudden death. 相似文献
Background: Leptin is a satiety hormone mainly produced by white adipose tissue. Decreasing levels have been described following acute stress. Objective: To conduct a systematic review and meta-analysis to determine if leptin can be a biomarker of stress, with levels decreasing following acute stress. Methods: PubMed, Cochrane Library, Embase, and ScienceDirect were searched to obtain all articles studying leptin levels after acute stress on 15 February 2021. We included articles reporting leptin levels before and after acute stress (physical or psychological) and conducted random effects meta-analysis (DerSimonian and Laird approach). We conducted Meta-regressions and sensitivity analyses after exclusion of groups outside the metafunnel. Results: We included seven articles—four cohort and three case-control studies—(28 groups) from 27,983 putative articles. Leptin levels decreased after the stress intervention (effect size = −0.34, 95%CI −0.66 to −0.02) compared with baseline levels, with a greater decrease after 60 min compared to mean decrease (−0.45, −0.89 to −0.01) and in normal weight compared to overweight individuals (−0.79, −1.38 to −0.21). There was no difference in the overweight population. Sensitivity analyses demonstrated similar results. Levels of leptin after stress decreased with sex ratio—i.e., number of men/women—(−0.924, 95%CI −1.58 to −0.27) and increased with the baseline levels of leptin (0.039, 0.01 to 0.07). Conclusions: Leptin is a biomarker of stress, with a decrease following acute stress. Normal-weight individuals and women also have a higher variation of leptin levels after stress, suggesting that leptin may have implications in obesity development in response to stress in a sex-dependent manner. 相似文献
In vivo cancer detection based on the mid-infrared molecular fingerprint of tissue is promising for the fast diagnosis and treatment of suspected cancer patients. Few materials are mid-infrared transmissive, even fewer, which can be converted into functional, low-loss optical fibres for in vivo non-invasive testing. Chalcogenide-based glass optical fibres are, however, one of the few. These glasses are transmissive in the mid-infrared and are currently under development for use in molecular sensing devices. The cytotoxicity of these materials is however unknown. The cytotoxicity of Ge–Sb–Se chalcogenide optical glass fibres on 3T3 mouse fibroblast cells is here investigated. Fibres exposed to four different pre-treatment conditions are used: as-drawn (AD), propylamine-etched (PE), oxidised-and-washed (OW) and oxidised (Ox). To achieve the latter two conditions, fibres are treated with H2O2(aqueous (aq.)) and dried to produce a surface oxide layer; this is either washed off (OW) or left on the glass surface (Ox). Cellular response is investigated via 3 day elution and 14 day direct contact trials. The concentration of the metalloids (Ge, Sb and Se) in each leachate was measured via inductively coupled plasma mass spectrometry. Cell viability is assessed using the neutral red assay and scanning electron microscopy. The concentration of Ge, Sb and Se ions after a 3 day dissolution was as follows. In AD leachates, Ge: 0.40 mg L−1, Sb: 0.17 mg L−1, and Se: 0.06 mg L−1. In PE leachates, Ge: 0.22 mg L−1, Sb: 0.15 mg L−1, and Se: 0.02 mg L−1. In Ox leachates, Ge: 823.8 mg L−1, Sb: 2586.6 mg L−1, and Se: 3750 mg L−1. Direct contact trials show confluent cell layers on AD, PE and OW fibres after 14 days, while no cells are observed on the Ox surfaces. A >50% cell viability is observed in AD, PE and OW eluates after 3 days, when compared with Ox eluates (<10% cell viability). Toxicity in Ox is attributed to the notable pH change, from neutral pH 7.49 to acidic pH 2.44, that takes place on dissolution of the surface oxide layer in the growth media. We conclude, as-prepared Ge–Sb–Se glasses are cytocompatible and toxicity arises when an oxide layer is forced to develop on the glass surface.We present a study that aims to evaluate the cytotoxicity of Ge20Sb10Se70 at% glass optical fibres on 3T3 mouse fibroblast cells. To observe the toxicity of these optical fibres, 3T3 fibroblast proliferation was investigated. 相似文献