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11.
Pneumonia is one of the leading causes of morbidity, hospitalization, and mortality in both industrialized and developing countries. In particular, pulmonary infections acquired in the community, and pneumonias arising in the hospital setting, represent a major medical and economic problem and thus a continuous challenge to health care. For the radiologist, it is important to understand that community-acquired pneumonia (CAP) and nosocomial pneumonia (NP) share a number of characteristics, but should, in many respects be regarded as separate entities. CAP and NP arise in different populations, host different spectra of causative pathogens, and pose different challenges to both the clinician and the radiologist. CAP is generally seen in outpatients, is most frequently caused by Streptococcus pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, and Chlamydia, and its radiologic diagnosis is relatively straightforward. NP, in contrast, develops in the hospital setting, is commonly caused by gram-negative bacteria, and may generate substantial problems for the radiologist. Overall, both for CAP and NP, imaging is an integral component of the diagnosis, important for classification and differential diagnosis, and helpful for follow-up.  相似文献   
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Corticotropin-releasing hormone receptor type 1 (CRH-R1)-deficient mice display reduced anxiety-like behavior, a chronic corticosterone deficit, and an impaired neuroendocrine stress response caused by disruption of the hypothalamic-pituitary-adrenocortical (HPA) axis. The molecular substrates and pathways of CRH/CRH-R1-dependent signaling mechanisms underlying the behavioral phenotype as well as the consequences of lifelong glucocorticoid deficit remain largely obscure. To dissect involved neuronal circuitries, we performed comparative expression profiling of brains of CRH-R1 mutant and wild-type mice using our custom made MPIP (Max Planck Institute of Psychiatry) 17k cDNA microarray. Microarray analysis yielded 107 genes showing altered expression levels when comparing CRH-R1 knockout mice with wild-type littermates. A significant proportion of differentially expressed genes was related to control of HPA and hypothalamic-pituitary-thyroid (HPT) axes reflecting not only the disturbance of the HPA axis in CRH-R1 mutant mice but also the interplay of both neuroendocrine systems. The spatial analysis of regulated genes revealed a prevalence for genes expressed in the cerebral microvasculature. This phenotype was confirmed by the successful cross-validation of regulated genes in CRH overexpressing mice. Analysis of the cerebral vasculature of CRH-R1 mutant and CRH overexpressing mice revealed alterations of functional rather than structural properties. A direct role of the CRH/CRH-R1 system was supported by demonstrating Crhr1 expression in the adult murine cerebral vasculature. In conclusion, these data suggest a novel, previously unknown role of the CRH/CRH-R1 system in modulating neurovascular gene expression and function.  相似文献   
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Preoperative cytologic examinations were performed on bronchial material from 92 patients with postsurgical (pathologic) stage I (American Joint Committee) adenocarcinoma of the lung. All patients were followed up for at least 5 years or until death; thus, cases of adenocarcinoma metastatic to the lungs were virtually excluded. Only 22 patients (24%) had abnormal preoperative cytologic findings. This low cytologic sensitivity is ascribed to the small size and peripheral location of the tumors. Large lesions of high histologic grades were more likely to have positive preoperative cytologic findings than small, well-differentiated ones.  相似文献   
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Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction.  相似文献   
17.
Abstract  – The dental records made on presentation of 1367 consecutive patients (731 females and 636 males) for orthodontic treatment at a private orthodontic practice between 1998 and 2002 were examined for data relating to trauma to the permanent incisors. The results showed that 10.3% of these patients had suffered from dental trauma before the onset of orthodontic treatment. The highest prevalence of dental trauma was determined in the 11–15 years age group, corresponding to the dental developmental stage of the late mixed dentition. The most frequently affected teeth were the maxillary central incisors (79.6%), and the most common types of trauma were fracture of enamel–dentin without pulpal involvement (42.7%) and fracture of enamel (33.8%). Compared to patients with normal overjet and adequate lip coverage, the frequency of dental trauma was significantly higher in patients with increased overjet and adequate lip coverage ( P  = 0.028) or with increased overjet and inadequate lip coverage ( P  = 0.003). The results of the present study indicate that a significant percentage of candidates for orthodontic treatment, and especially those with increased overjet and inadequate lip coverage, suffer trauma to their permanent incisors before the onset of orthodontic treatment. It might also be concluded that preventive orthodontic treatment of such patients should be initiated and completed before the age of 11, i.e. in the early to middle mixed dentition.  相似文献   
18.
We report the first large-scale double-blind, randomly assigned study to compare two active dopaminergic therapies for Restless Legs Syndrome (RLS), the dopamine agonist cabergoline (CAB) and levodopa/benserazide (levodopa). Patients with idiopathic RLS were treated with fixed daily doses of 2 or 3 mg CAB or 200 or 300 mg levodopa for 30 weeks. Efficacy was assessed by changes in the IRLS (International RLS Severity Scale) and by time to discontinuation of treatment due to loss of efficacy or augmentation. 361 of 418 screened patients (age 58 +/- 12 years, 71% females) were randomly assigned and treated (CAB: n = 178; levodopa: n = 183) in 51 centers of four European countries. Baseline IRLS total score was 25.7 +/- 6.8. The baseline-adjusted mean change from baseline to week 6 in IRLS sum score was d = -16.1 in the CAB group and d = -9.5 in the levodopa group (d = -6.6, P < 0.0001). More patients in the levodopa group (24.0%) than in the CAB group (11.9%, P = 0.0029, log-rank test) discontinued because of loss of efficacy (14.2% vs. 7.9%, P = 0.0290) or augmentation (9.8% vs. 4.0%, P = 0.0412). Adverse events (AEs) occurred in 83.1% of the CAB group and in 77.6% of the levodopa group. In both groups, most frequent AEs were gastrointestinal symptoms (CAB: 55.6%, levodopa: 30.6%, P < 0.0001). This first large-scale active controlled study in RLS showed superior efficacy of cabergoline versus levodopa after a 30-week long-term therapy. Tolerability was found more favorable with levodopa than with cabergoline.  相似文献   
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There remains doubt about the need for gastroenterostomy in patients with advanced cancer of the pancreatic head, performed either prophylactically or when passage of food becomes impossible. The records of 142 patients admitted for advanced pancreatic cancer to the Erasmus University Hospital over a period of 11 years were reviewed. We concentrated especially on the pre- and postoperative intake of food in cases involving gastroenterostomy and the morbidity and mortality associated with abdominal surgery in these patients. Of 129 patients without symptoms of gastric outlet obstruction at the time of diagnosis, 31 underwent prophylactic gastroenterostomy. The procedure did not prevent gastric outlet obstruction in 4 patients. Of the remaining 98 patients, 15 developed gastric outlet obstruction. Cox proportional hazards analysis showed no significant difference in the interval to the occurrence of a symptomatic obstruction between these two groups, taking into account other covariables. Postoperative complications and mortality regarding a gastroenterostomy were high, ranging from 9% to 41% and 11% to 33%, respectively. Our results do not indicate that prophylactic gastroenterostomy may significantly prevent future gastric outlet obstruction; therefore, as it also increases morbidity, it should not be performed. A gastroenterostomy to relieve symptoms should be considered carefully, as the success rate is low and is accompanied by a considerable incidence of morbidity and mortality.
Resumen Persiste la duda sobre la necesidad de practicar gastroenterostomía en pacientes con cáncer avanzado de la cabeza del páncreas, así sea profiláctica o en presencia de obstrucción al paso de los alimentos. Se revisaron las historias de 142 pacientes con cáncer avanzado de la cabeza del páncreas en el Hospital de la Universidad de Erasmo observados en un periodo de 11 años. El estudio se concentré especialmente sobre la ingesta pre y postoperatoria de alimentos en los pacientos con gastroenterostomía y en la morbilidad y mortalidad asociada con la cirugía abdominal. De 129 pacientes libres de síntomas de obstrucción en el momento del diagnóstico, 31 fueron sometidos a gastroenterostomía profiláctica; el procedimiento no logró prevenir la obstrucción gástrica en 4 casos. De los 98 pacientes restantes, 15 desarrollaron obstrucción gástrico. El análisis proporcional de Cox no demostró diferencia significativa en el intervalo transcurrido hasta la aparición de los sintomas entre los dos grupos, tomando en consideración diversas variables. Las tasas de complicaciones y de mortalidad postoperatoria en relación con la gastroenterostomía fueron elevadas, 9–41% y 11–33%, respectivamente. Nuestros resultados no indican que la gastroenterostomía profiláctica pueda prevenir la obstrucción gástrica y, por cuanto incrementa la morbilidad, no debe ser realizada. La gastroenterostomía por razones de sintomatologia debe ser cuidadosamente considerada, puesto que la tasa de éxito es baja y se acompana de considerable morbilidad y mortalidad.

Résumé Réaliser une gastroentérostomie de faÇon prophylactique ou seulement lorsque l'alimentation devient impossible chez un patient ayant un cancer de la tÊte du pancréas reste une question sans réponse. Les dossiers de 142 patients ayant un cancer avancé de la tÊte du pancréas, observés à l'HÔpital Universitaire Erasmus en l'espace de 11 ans, ont été revus. Nous avons noté la possibilité d'alimentation en périodes préet postopératoire ainsi que la morbidité et mortalité en rapport avec la chirurgie chez ces patients. Des 129 patients n'ayant pas de symptÔmes d'obstruction postpylorique au moment du diagnostic, 31 ont eu une gastroentérostomie à titre prophylactique. Cette intervention n'a pu prévenir l'obstruction chez 4 de ces patients. Des 98 autres patients, 15 ont développé une obstruction postpylorique. Une analyse multifactorielle selon le modèle de Cox n'a pu démontrer de différence significative entre les deux groupes pour l'intervalle entre le moment du diagnostic et la survenue de l'obstruction. Le taux de complications et de décès postopératoires après gastroentérostomie était élevée, variant respectivement entre 9% et 41% et 11% et 33%. Nos résultats indiquent que la gastroentérostomie à titre prophylactique ne prévient pas la survenue d'une obstruction postpylorique mais qu'elle accroÎt la morbidité. Dans ces conditions, la gastroentérostomie ne devrait Être réalisée qu'en cas d'obstruction symptomatique, mais en sachant qu'elle n'est pas toujours couronnée de succès et que les taux de mortalité et de morbidité ne sont pas nuls.
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