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31.
This multi-voxel, phosphorus magnetic resonance spectroscopy (31P MRS) study examined the prefrontal cortex (PFC), basal ganglia (BG) and superior temporal (ST) region in 10 children with attention-deficit/hyperactivity disorder (ADHD) and 15 healthy controls. ADHD patients had lower PFC and BG phosphomonoester (PME) levels compared to healthy children. No differences were noted in the ST. These deficits in membrane phospholipid (MPL) precursor levels suggest reduced mass of cellular MPLs due to a possible underdevelopment of neuronal processes and synapses in ADHD.  相似文献   
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BACKGROUND: Prior pilot investigation identified a larger pituitary gland volume (PGV) in pediatric patients with major depressive disorder (MDD) compared with healthy pediatric control subjects that was most prominent in boys with MDD. In this independent sample, we focus on gender differences in pituitary volume in a larger sample of pediatric patients with MDD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 35 psychotropic drug-na?ve children (15 boys, 20 girls), ages 8-17 years, and 35 case-matched healthy control subjects. RESULTS: The MDD boys had larger PGV (19%) compared with male control subjects. No significant diagnostic group differences in pituitary volume were observed in girls. Healthy boys had significantly smaller PGV (27%) than healthy girls, whereas MDD boys did not differ from girls with MDD. Nonfamilial (without a family history of mood disorder) boys with MDD had significantly larger PGV (35%) than male healthy control subjects and tended to have a larger PGV (27%) than familial (at least one first-degree relative with MDD) boys with MDD. Boys with familial MDD did not differ from control subjects. CONCLUSIONS: These findings provide new evidence of increased pituitary volume in psychotropic-na?ve pediatric patients with MDD that seems to be more prominent in male patients with nonfamilial MDD.  相似文献   
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BACKGROUND: Pantoprazole is a substituted benzimidazole which is a potent inhibitor of gastric acid secretion by its action upon H+, K+- ATPase. METHODS: Pantoprazole 40 mg and 80 mg were compared in a randomized double-blind study in 192 out-patients with stage II or III (Savary-Miller classification) reflux oesophagitis. Patients received either pantoprazole 40 mg (n = 97) or pantoprazole 80 mg (n = 95), once daily before breakfast for 4 weeks. Treatment was extended for a further 4 weeks if the oesophagitis had not healed. RESULTS: After 4 weeks complete healing of the reflux oesophagitis was seen in 78% of protocol-correct patients given pantoprazole 40 mg daily (n = 86), and in 72% in the 80 mg (n = 87) group. The cumulative healing rates after 8 weeks were 95 and 94%, respectively (P > 0.05, Cochran-Mantel- Haenszel), and time until healing of oesophagitis comparable in both groups. Differences between doses were also not significant in an intention-to-treat analysis. Both dosing schedules were well tolerated and the patients experienced remarkable symptom relief. No adverse event or changes in laboratory values of clinical significance could definitely be ascribed to the trial medication. CONCLUSION: The 40 mg pantoprazole dosage is comparable to 80 mg in reflux oesophagitis, both in efficacy and tolerability.  相似文献   
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DA Christakis  FP Rivara 《Pediatrics》1998,101(5):825-830
BACKGROUND: The increasing complexity of medical care and a desire to increase quality and control costs have led to growing use of clinical practice guidelines (CPGs). It is unclear how helpful these guidelines are to the practitioners expected to use them. We surveyed pediatricians about their knowledge and impressions of four well-publicized CPGs: the American Academy of Pediatrics' "Practice Parameter for Hyperbilirubinemia in Newborns" (hyperbilirubinemia), "A Guideline for the Management of Febrile Infants" (fever), the Agency for Health Care Policy and Research's "Guideline for Otitis Media With Effusion" (otitis), and the US Preventive Services Task Force Guide to Clinical Preventive Services (preventive care). OBJECTIVES: 1) What percentage of practicing pediatricians are aware of these guidelines? 2) How helpful do they find them? 3) What are practitioners' perceived limitations of these guidelines? 4) Have these guidelines affected provider behavior? 5) Are there features of a provider's training or practice that are associated with changing practice as a result of guidelines? DESIGN: A national survey of 600 pediatricians selected at random from the American Medical Association master file. RESULTS: A total of 300 of 555 eligible participants (54%) returned surveys. Of the respondents, 66% were aware of the hyperbilirubinemia guideline, 64% of the fever guideline, 50% of the otitis guideline, but only 16% knew of the preventive care guidelines. Mean helpfulness scores (1 to 10 scale, where 1 = "not at all helpful" and 10 = "extremely helpful") ranged from 3.67 to 6.67 for the different guidelines. In terms of limitations, 15% to 33% of respondents reported that CPGs were "too cookbook," 6% to 19% reported that they were "too time-consuming," and 4% to 16% reported that they were "too cumbersome." Additional reported limitations were believing that a guideline left no room for personal experience and judgment, concern of increased liability risk, and poor parental acceptance of CPG recommendations. The proportions reporting change in management as a result of a CPG were 28% for the hyperbilirubinemia guideline, 36% for the fever guideline, 19% for the preventive care guidelines, and 28% for the otitis guideline. Mean helpfulness scores reported by nonuniversity-affiliated physicians were significantly higher than those reported by university-affiliated physicians. In a regression model of respondents aware of a particular guideline, more recent graduation from medical school and increased helpfulness scores were associated with guideline-related behavior change. CONCLUSION: In their present form, CPGs are not perceived as very helpful by most practitioners. More recent medical school graduates and nonuniversity-affiliated physicians are more likely to find them helpful and more likely to change their behavior because of them.  相似文献   
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The femur length/abdominal circumference ratio, expressed as FL/AC X 100, was determined in 156 fetuses and evaluated as a predictor of fetal macrosomia within one week prior to delivery. The normal range (mean +/- 2 SD) in the 105 normal-weight fetuses was 22.0 +/- 2, while the normal range in the 51 macrosomic fetuses was 20.5 +/- 2; these differences were highly significant (P = less than .0001). The predictive power of a positive ratio was 68%, with a sensitivity of 63%. This ratio was particularly useful in the subset (n = 9) of macrosomic fetuses whose mothers were diabetic, correctly identifying 89% of this group. Because it is age independent, this ratio should prove most helpful in identifying fetuses at risk for macrosomia in patients whose dates are not known, since it may become abnormal before the fetal weight falls above the 90th percentile at term (3,900 g). In patients whose dates are known, early fetal macrosomia is best predicted by evaluating the abdominal circumference against normal standards for age.  相似文献   
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Medical treatment of patients inherently entails the risk of undesired complication or side effects. It is essential to inform the patient about the expected outcomes, but also the possible undesired outcomes. The patients preference and values regarding the potential outcomes should be involved in the decision making process. Even though many orthopaedic surgeons are positive towards shared decision-making, it is minimally introduced in the orthopaedic daily practice and decision-making is still mostly physician based. Decision aids are designed to support the physician and patient in the shared- decision-making process. By using decision aids, patients can learn more about their condition and treatment options in advance to the decision-making. This will reduce decisional conflict and improve participation and satisfaction.  相似文献   
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