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The present report describes psychobiological studies of behavior around the time of birth. An adaptive, ecological perspective is presented in which stimulation of the fetus and newborn is purported to instigate adaptive postpartum behavior. Studies describing the perinatal sensory environment are reviewed, with a consideration of emergent sensory function of the fetus. It is asserted that afferent input associated with parturition perturbs the fetus and neonate, producing a general arousal state that facilitates breathing, suckling, and early learning. The view developed herein is that perinatal sensory input induces and canalizes the newborn's behavior, thereby regulating adaptive postpartum function. Deviations in afferent input may alter ontogenetic trajectories and compromise developmental outcome by reducing availability of conditions necessary for adequate postpartum adaptation.  相似文献   
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OBJECTIVE: To investigate the frequency of lumbosacral anomalies, the association with urogenital abnormalities, and the correlation with defaecation pattern by magnetic resonance imaging (MRI). METHODS: A prospective analysis was performed of routine MRI in patients with anorectal malformations. Between 1990 and 1994, MRI was performed in 43 such patients: 31 boys and 12 girls. Twenty four had a high anorectal malformation, 16 had a low anorectal malformation, and three had Currarino's triad. MRI was performed before reconstruction in 26, and postoperatively in 17. Urogenital anomalies were found in 21. RESULTS: Abnormalities of the spinal cord and spine were found with MRI in 20 patients (46.5%); caudal regression syndrome in 10, tethered cord in two, a combination of both in three, and other spinal anomalies in five. These anomalies were found in 30% of the patients with low anorectal malformations, and in 50% with high anorectal malformations. In patients with urogenital malformations, MRI more often showed spinal anomalies (13/21, 62%) than in patients without (7/22, 32%). In high anorectal malformations, defaecation was more often a problem in patients with spinal anomalies (12/15, 80%) than in patients without (2/8, 25%). CONCLUSIONS: Spinal anomalies in the lumbosacral region were found with MRI in 46.5% of patients with anorectal malformations. Since presence of these anomalies seems to be related to clinical outcome, MRI should be performed routinely in all such patients.  相似文献   
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Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover.  相似文献   
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Widespread Castleman disease: CT and US findings   总被引:4,自引:0,他引:4  
The widespread form of Castleman disease is a rare condition that has been recognized only recently as a disease with an aggressive, often malignant course. The authors present computed tomographic (CT) findings in six patients with this condition and ultrasound (US) findings in four of the six. CT demonstrated splenomegaly and retroperitoneal lymphadenopathy in all six patients. In one patient, CT also showed additional widespread mesenteric and peripancreatic lymphadenopathy, a large mesenteric mass adherent to the descending colon in another, and mediastinal lymphadenopathy in a third. Three patients had peripheral axillary or inguinal lymphadenopathy. Enlarged lymph nodes were 1-4 cm in diameter, and none displayed contrast enhancement on CT scans obtained with drip infusion of contrast media. On US scans, the nodes were poorly echogenic in all four cases. In no case was focal liver or splenic infiltration seen on either CT or US scans.  相似文献   
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