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1.
Ameloblastic carcinoma (AC) is an aggressive malignant epithelial odontogenic tumor. It may appear de novo or originate from a pre-existing ameloblastoma or odontogenic cyst. To our knowledge, an AC that originates from the anterior skull base has not been reported before in the English literature. We report a case of an AC that originated from the anterior skull base and invaded the dura of the anterior fossa and discuss its clinical course and treatment.  相似文献   
2.
Products of the Frizzled family of tissue polarity genes have been identified as putative receptors for the Wnt family of signaling molecules. Wnt-signaling is implicated in the regulation of limb mesenchymal chondrogenesis, and our recent study indicates that N-cadherin and related activities are functionally involved in Wnt-7a-mediated inhibition of chondrogenesis. By using an in vitro high-density micromass culture system of chick limb mesenchymal cells, we have analyzed the spatiotemporal expression patterns and the effects on chondrogenesis of RCAS retroviral-mediated misexpression of Chfz-1 and Chfz-7, two Frizzled genes implicated in chondrogenic regulation. Chfz-1 expression was localized at areas surrounding the cartilaginous nodules at all time points examined, whereas Chfz-7 expression was limited to cellular aggregates during initial mesenchymal condensation, and subsequently was down-regulated from the centers toward the periphery of cartilage nodules at the time of chondrogenic differentiation, resembling the pattern of N-cadherin expression. Chondrogenesis in vitro was inhibited and limited to a smaller area of the culture upon misexpression of Chfz-7, but not affected by Chfz-1 misexpression. Analyses of cellular condensation and chondrogenic differentiation showed that the inhibitory action of Chfz-7 is unlikely to be at the chondrogenic differentiation step, but instead affects the earlier precartilage aggregate formation event. At 24 hr, expression of N-cadherin, a key component of the cellular condensation phase of chondrogenesis, was delayed/suppressed in Chfz-7 misexpressing cultures, and was limited to a significantly smaller cellular condensation area within the entire culture at 48 hr, when compared with control cultures. Chfz-1 misexpressing cultures appeared similar to control cultures at all time points. However, neither Chfz-1 nor Chfz-7 misexpression affected mesenchymal cell proliferation in vitro. These results suggest that Chfz-7 is active in regulating N-cadherin expression during the process of limb mesenchymal chondrogenesis and that Chfz-1 and Chfz-7 are involved in different Wnt-signaling pathways.  相似文献   
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Experiments 1 and 2 address the controversy regarding the reliability of methamphetamine effects on interval timing. A temporal discrimination procedure was used, in which the rats were reinforced for pressing the left or the right levers after short and long signals, respectively. Methamphetamine (0.5 mg/kg sc) severely disrupted operant performance at 20-100 min after injection, which disabled the measurement of drug effects on temporal perception (Experiment 1). The same dose of methamphetamine shifted the psychometric function to the left at 100-180 min after injection, indicating an increase in subjective durations (Experiment 2). Although these results confirm the role of dopamine in interval timing, that a change in the speed of a neural clock mediates the methamphetamine-induced change in temporal perception is still a working hypothesis.  相似文献   
5.
Is obesity a risk factor for psychopathology among adolescents?   总被引:6,自引:0,他引:6  
BACKGROUND: Although several studies have documented the existence of psychopathology in obese adolescents, disagreement remains regarding the extent and nature of this psychopathology. The aim of the present study was to explore the type and frequency of psychopathology in a clinical as well as a non-clinical sample of obese adolescents, and in a normal weight control group. METHODS: The study sample consisted of a clinical study group of 30 obese adolescents, a non-clinical obese group of 30 obese adolescents, and a control group of 30 normal weight adolescents. Psychological assessment was performed using a non-structured psychiatric interview, the Child Behavior Checklist (CBCL), Children Depression Inventory (CDI), Rosenberg Self-esteem scale (SES) and the Eating Attitude Test (EAT). RESULTS: More than half of the clinical obese adolescents (16/30) had a DSM-IV diagnosis, often involving major depressive disorder (n = 10). The mean scores of anxiety-depression, social problems, social withdrawal and total problem in the CBCL scale of the clinical obese group were significantly higher than the non-clinical obese group and the normal weight control group. The mean total scores of the SES and the CDI of the clinical obese group were higher than the normal weight control group. The mean total score of EAT of the clinical obese group was significantly higher than the normal weight control group, and the mean score of EAT of the non-clinical obese group was significantly higher than the normal weight control group. CONCLUSIONS: The results support previously published reports which show a higher ratio of psychopathology (depression, behavioral problems, low-esteem) among clinical obese adolescents than among non-clinical obese adolescents. Findings provided evidence for a psychosocial at-risk population in a subgroup of obese adolescents.  相似文献   
6.
OBJECTIVES: To determine the differences in and factors related to satisfaction between barrier (male condom) and non-barrier method users. METHODS: A semi-structured questionnaire was used for collecting data for this cross-sectional survey. The questionnaires were completed via one-on-one interviews by the researchers. The study group was selected using stratified random sampling. Exclusion criteria were, being unmarried, pregnant, in postmenopausal status and using traditional methods. A total of 434 currently married women using modern contraceptive methods participated in the study. Contraceptive users were dichotomized into two groups as non-barrier method users and barrier method users. RESULTS: About half of the participants (n = 191, 44%) were barrier method users. Their mean age was 33.7 +/- 7.3 years, 66.6% (n = 131) were well educated and reported significantly less pregnancies, given births, living children and abortions (reproductive history events) than non-barrier users. Barrier method users were significantly more likely to be satisfied with their contraceptive method of choice (OR: 2.4; 95% CI 1.2-5.2). Among barrier method users, deciding the type of the contraceptive method themselves had significant effect on satisfaction.CONCLUSION: In our study, satisfaction was mostly affected by heavy side effects and health risks of the methods resulting in less satisfaction with the contraceptive method among non-barrier method users. Other factors which may influence satisfaction deserve further investigation.  相似文献   
7.
The aim of this study was to investigate the possible effects of ellagic acid in brain and sciatic nerve tissues of diabetic rats. Also, the impact of ellagic acid on catalase and paraoxonase (PON-1) activities, total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), malondialdehyde (MDA) and nitric oxide (NO) were examined. The rats were randomly divided into four groups, with eight rats each: Normal controls (not diabetic), only ellagic acid treated (ellagic acid controls, not diabetic), Diabetic controls (streptozotocin, diabetic), ellagic acid-treated diabetic (streptozotocin?+?ellagic acid). After a 4?week experiment, rats were sacrificed, and biomarkers for oxidative stress in the brain and sciatic nerve tissues of the rats were measured. There was significant depletion in the PON-1, catalase, and TAS levels in the brain and sciatic nerve tissues compared to the control groups (for both parameters, p?<?0.05). The values of catalase, PON-1 and TAS reversed back to normal levels in ellagic acid-treated diabetic rats compared to untreated diabetic rats (for both parameters, p?<?0.05). The levels of MDA, TOS, NO and, OSI in the brain and sciatic nerve tissues were higher in untreated diabetic rats compared to control group (for both parameters p?<?0.05). However, MDA, TOS, OSI, and NO levels were found to be significantly reduced in the ellagic acid-treated diabetic group compared to the untreated diabetic group in these tissues (for both parameters, p?<?0.05). In conclusion, the results of the present study suggested that ellagic acid exhibits neuroprotective effects against oxidative damage in diabetic rats.  相似文献   
8.
Alpha lipoic acid (ALA), which is an anti-oxidant acting as a scavenger for reactive oxygen species, is especially used to improve glycemic control and prevent polyneuropathies associated with diabetes mellitus. ALA is considered to be a safe drug and intoxication with ALA is extremely rare. However, this paper reports a 38-year-old young woman who was admitted to the emergency department after she had ingested ten pills of 600 mg ALA belonging to her diabetic parent, which led to delirium, metabolic acidosis, thrombocytopenia, and rhabdomyolysis. To the best of our knowledge, there are only four cases of ALA intoxication reported in the literature and all were observed in children. This report aims to present the first case of ALA related intoxication worldwide in an adult patient.  相似文献   
9.
The primary cause of preventable death in many hospitals is the failure to recognize and/or rescue patients from acute physiologic deterioration (APD). APD affects all hospitalized patients, potentially causing cardiac arrest and death. Identifying APD is difficult, and response timing is critical - delays in response represent a significant and modifiable patient safety issue. Hospitals have instituted rapid response systems or teams (RRT) to provide timely critical care for APD, with thresholds that trigger the involvement of critical care expertise. The National Early Warning Score (NEWS) was developed to define these thresholds. However, current triggers are inconsistent and ignore patient-specific factors. Further, acute care is delivered by providers with different clinical experience, resulting in quality-of-care variation. This article documents a semi-Markov decision process model of APD that incorporates patient and provider heterogeneity. The model allows for stochastically changing health states, while determining patient subpopulation-specific RRT-activation thresholds. The objective function minimizes the total time associated with patient deterioration and stabilization; and the relative values of nursing and RRT times can be modified. A case study from January 2011 to December 2012 identified six subpopulations. RRT activation was optimal for patients in “slightly concerning” health states (NEWS?>?0) for all subpopulations, except surgical patients with low risk of deterioration for whom RRT was activated in “concerning” states (NEWS?>?4). Clustering methods identified provider clusters considering RRT-activation preferences and estimation of stabilization-related resource needs. Providers with conservative resource estimates preferred waiting over activating RRT. This study provides simple practical rules for personalized acute care delivery.  相似文献   
10.
BackgroundThe information on electrocardiographic features of patients with coronavirus disease 2019 (COVID-19) is limited. Our aim was to determine if baseline electrocardiographic features of hospitalized COVID-19 patients are associated with markers of myocardial injury and clinical outcomes.MethodsIn this retrospective, single center cohort study, we included 223 hospitalized patients with laboratory-confirmed COVID-19. Clinical, electrocardiographic and laboratory data were collected and analyzed. Primary composite endpoint of mortality, need for invasive mechanical ventilation, or admission to the intensive care unit was assessed.ResultsForty patients (17.9%) reached the primary composite endpoint. Patients with the primary composite endpoint were more likely to have wide QRS complex (>120 ms) and lateral ST-T segment abnormality. The multivariable Cox regression showed increasing odds of the primary composite endpoint associated with acute respiratory distress syndrome (odds ratio 7.76, 95% CI 2.67–22.59; p < 0.001), acute cardiac injury (odds ratio 3.14, 95% CI 1.26–7.99; p = 0.016), high flow oxygen therapy (odds ratio 2.43, 95% CI 1.05–5.62; p = 0.037) and QRS duration longer than >120 ms (odds ratio 3.62, 95% CI 1.39–9.380; p = 0.008) Patients with a wide QRS complex (>120 ms) had significantly higher median level of troponin T and pro-BNP than those without it. Patients with abnormality of lateral ST-T segment had significantly higher median level of troponin T and pro-BNP than patients without.ConclusionsThe presence of QRS duration longer than 120 ms and lateral ST-T segment abnormality were associated with worse clinical outcomes and higher levels of myocardial injury biomarkers.  相似文献   
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