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941.
942.
Haemangiopericytoma is a vascular, soft tissue neoplasm with rare occurrence in the head and neck region. On the basis of literature we discuss etiology, symptomatology, histopathology, diagnosis, treatment and prognosis. We present the case of 66-old woman with haemangiopericytoma in the parotid gland treated by surgery.  相似文献   
943.
BACKGROUND: Perinatal asphyxia constitutes a significant problem influencing neonatal mortality and morbidity. OBJECTIVES: The aim of the present work was to provide evidence of the usefulness of cardiac troponin T (cTnT) and echocardiographic investigations in the diagnosis of heart damage in full-term infants after intrauterine hypoxia. MATERIAL AND METHODS: The subjects were 39 asphyxiated and 44 term infants without fetal anoxia. Quantitative determinations of cTnT were performed between 12 and 24 h of life. Two-dimensional Doppler and color Doppler studies were performed at the bedside. We evaluated fractional shortening (FS), cardiac output (CO), cardiac index (CI), tricuspid (TI) and mitral (MI) insufficiency. RESULTS: Asphyxiated infants presented increased cTnT (mean 0.141+/-0.226 vs. 0.087+/-0.111 ng/ml; p<0.01) and TI (38.5 vs. 11.4% of population; p<0.05) compared to healthy infants. CO, CI and FS remained in the same range. CONCLUSIONS: We found cTnT to be the most useful among accessible diagnostic tools used in post-hypoxic heart damage in neonates. The data from our relatively small population study suggest a cTnT value of >0.1 ng/ml as a reliable marker of myocardial injury in neonates. Further study should be performed to generate a receiver-operator characteristic curve to discover what the cut-off level should be.  相似文献   
944.
945.
Helicobacter pylori-associated diseases, such as peptic ulcer and gastric cancer, are common in Vietnam, but the prevalence of the infection is largely unknown. A validated enzyme-linked immunosorbent assay was used for seroepidemiology with 971 samples from the general population, ages 0 to 88 years, with 546 samples from an urban population (Hanoi), and with 425 samples from a poor, rural province (Hatay). The overall seroprevalence of the infection was 746 per 1,000, with a prevalence of 788 per 1,000 in Hanoi and 692 per 1,000 in Hatay (P=0.0007). The risk for infection in the rural area of Hatay was 40% lower than in the urban population of Hanoi, with the odds ratio being 0.59 (95% confidence interval, 0.43 to 0.81). The study shows that the prevalence of H. pylori infection is high in Vietnam and especially high in a large urban area, such as the city of Hanoi.  相似文献   
946.
947.
The purpose of this study was to determine the basal levels of dopamine (DA) and to examine the enzymes involved in DA metabolism in different microdissected nephron segments from rat kidneys. Segments were incubated with DA (50 nM) or DA plus monoamine oxidase (MAO) or catechol-O-methyl transferase (COMT) inhibitors. Basal DA levels were higher in the proximal convoluted tubule (PCT, 10.8±3.7 pg/mm) and in the medullary collecting duct (MCD, 10.9±4.0 pg/mm) than in the medullary thick ascending limb of Henles loop (MTAL, 4.9±0.9 pg/mm) (P<0.05). The percentage of exogenously added DA that was not metabolised was similar in both PCT (67±13%) and MCD (65±5%) and lower in MTAL (35±7%), suggesting that MTAL is a major site of DA metabolism. Inhibition of MAO (pargyline 1 mM) significantly increased the basal content of DA and the percentage of the added non-metabolised DA (to 95±10%) in PCT but had no effect on MTAL or MCD. Conversely, inhibition of COMT (nitecapone or Ro-41-0960, both 1 mM) slightly increased the basal levels of DA only in MTAL, whereas the percentage of added DA not metabolised rose to 97±10% in MTAL and to 91±15% in MCD. COMT inhibition had no effect in PCT. In conscious rats pargyline (50 mg/kg) increased urinary DA from 680±34 to 1,128±158 ng/d/100 g BW (P<0.01) while nitecapone (40 mg/kg) produced a slight non-significant increment. Our results show that DA is present all along the rat nephron and that renal DA is metabolised continuously and predominantly by MAO in proximal segments, and by COMT in the more distal ones.  相似文献   
948.
DYRK1A, dual-specificity tyrosine-regulated kinase 1A, maps to human chromosome 21 within the Down syndrome (DS) critical region. Dyrk1 phosphorylates the human microtubule-associated protein tau at Thr212 in vitro, a residue that is phosphorylated in fetal tau and hyper-phosphorylated in Alzheimer disease (AD) and tauopathies, including Pick disease (PiD). Furthermore, phosphorylation of Thr212 primes tau for phosphorylation by glycogen synthase kinase 3 (GSK-3). The present study examines Dyrk1A in the cerebral cortex of sporadic AD, adult DS with associated AD, and PiD. Increased Dyrk1A immunoreactivity has been found in the cytoplasm and nuclei of scattered neurons of the neocortex, entorhinal cortex, and hippocampus in AD, DS, and PiD. Dyrk1A is found in sarkosyl-insoluble fractions which are enriched in phosphorylated tau in AD brains, thus suggesting a possible association of Dyrk1A with neurofibrillary tangle pathology. Yet, no clear relationship has been observed between tau phosphorylation at Thr212, and GSK-3 and Dyrk1A expression in diseased brains. Transgenic mice bearing a triple tau mutation (G272V, P301L, and R406W) and expressing hyper-phosphoyrylated tau in neurons of the entorhinal cortex, hippocampus, and cerebral neocortex show increased expression of Dyrk1A in individual neurons in the same regions. However, transgenic mice over-expressing Dyrk1A do not show increased phosphorylation of tau at Thr212, thus suggesting that Dyrk1A over-expression does not trigger per se hyper-phosphorylation of tau at Thr212 in vivo. The present observations indicate modifications in the expression of constitutive Dyrk1A in the cytoplasm and nuclei of neurons in various neurodegenerative diseases associated with tau phosphorylation.  相似文献   
949.
Evidence-based medicine (EBM) is defined as a set of processes that facilitate the conscientious, explicit, and judicious integration of individual clinical expertise with the best available external clinical evidence from systematic research in making decisions about the care of individual patients. EBM focuses not only on grading the strength of the evidence but also on the processes and tools that are necessary for clinicians to continually upgrade their knowledge and skills for those problems encountered in daily practice. This article, authored by members of the Duke Pediatric Psychiatry EBM Seminar Team, (1) describes EBM as applied to the training of child and adolescent psychiatrists in the Division of Child and Adolescent Psychiatry, Department of Psychiatry at Duke University Medical Center; (2) presents a simplified discussion of EBM as a technology for training and patient care; (3) discusses the basic principles and procedures for teaching EBM in the setting of a multidisciplinary training program; and (4) briefly mentions two training and research initiatives that are furthered by incorporating EBM.  相似文献   
950.
One hundred and four male patients hospitalized for the first time with the diagnosis of first-episode schizophrenia were comprehensively assessed on admission and discharge. Psychopathology, treatment response, and remission rates were evaluated (based on the Positive and Negative Syndrome Scale (PANSS), severity of symptoms only). On admission, the most frequently observed symptoms were lack of judgment and insight (87.6%), suspiciousness/feelings of persecution (82.3%), delusions (77%), poor attention (70%), disturbance of volition (65.4%), conceptual disorganization (64.7%), and active social avoidance (64%). Except for delusions and hallucinations, the positive items of the PANSS correlated significantly with negative symptoms, and conceptual disorganization correlated with the greatest number of negative symptoms. Individual negative symptoms were present in about half the patients. At discharge, the most frequent symptoms were again lack of judgment and insight (in 55.7%), and for negative symptoms they were blunted affect (22.1%), emotional withdrawal (21.2%), and passive/apathetic social withdrawal (19.5%). The positive symptoms of suspiciousness/feelings of persecution and grandiosity persisted in 20.6% of patients. On average, all symptoms were significantly reduced 44 days after admission. The negative symptoms improved less, compared with the positive ones. At discharge there was a high rate of responders (response defined as minimal 30% reduction of total PANSS): 73% and 74% of patients fulfilled the criteria for remission. On admission, the responders (n = 76) had significantly higher scores of most symptoms, both positive and negative ones than nonresponders (n = 28).  相似文献   
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