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991.
Face encoding and psychometric testing in healthy dextrals with right hemisphere language 总被引:3,自引:0,他引:3
OBJECTIVE: To document how right hemisphere language dominance in neurologically normal right-handed individuals affects lateralization of face encoding and level of performance in neuropsychological tests. METHODS: Three healthy right-handed adults with predominantly right hemisphere language activation during single-word or sentence-level processing were identified from 210 consecutive right-handed subjects studied using blood oxygenation level-dependent contrast fMRI. These three study subjects (S1 to S3) underwent a second scanning session where they performed word and face encoding. Their functional scans were contrasted with those obtained from six healthy control subjects (C1 to C6) with left hemisphere language dominance. Psychometric tests were performed on the study subjects. RESULTS: Right hemisphere-dominant language activation was reproduced in the second scanning session in the three study subjects. The extent to which the lateralization of face encoding was reversed varied. Right hemisphere language was associated with lower (but within normal) verbal IQ compared with performance IQ in two of three volunteers. Verbal and nonverbal memory scores were normal and did not differ appreciably. CONCLUSION: Right hemisphere-dominant language in healthy dextrals exists but is rare. The extent to which face encoding is reversed in these individuals is variable. Cognitive function does not appear to be significantly compromised even though some psychometric test scores are asymmetric in favor of nonverbal performance when the reversal of lateralization of face and word memory is not complete. 相似文献
992.
Inasmuch as long-chain polyunsaturated fatty acids (PUFA, metabolites of the essential n-3 and n-6 fatty acids) are known to modulate inflammation, we hypothesized that supplementation of formula with these compounds would prevent necrotizing enterocolitis (NEC) and intestinal inflammation in our neonatal rat model. Newborn rats were stressed with asphyxia and formula feeding, and randomly assigned to control formula, control with PUFA supplementation, and PUFA with nucleotides. Animals were followed for 72--96 h and assessed for death, gross and histologic NEC, intestinal apoptosis, endotoxemia, and intestinal mRNA synthesis of phospholipase A(2)-II (rate-limiting enzyme for platelet activating factor production), platelet activating factor receptor, and inducible nitric oxide synthase. We found that PUFA reduced the incidence of death and NEC compared with the other groups (NEC 8 of 24 versus 17 of 24 control and 13 of 23 PUFA + nucleotides, p < 0.05). Furthermore, PUFA reduced plasma endotoxemia at 48 h (25 +/- 4 EU/mL versus 276 +/- 39 EU/mL in control and 170 +/- 28 EU/mL in PUFA + nucleotide), intestinal phospholipase A(2)-II expression at 24 h, and platelet activating factor receptor expression at 48 h. Formula supplementation had no effect on apoptosis of intestinal epithelium or intestinal inducible nitric oxide synthase expression. Addition of nucleotides with PUFA abrogated the beneficial effects of PUFA on intestinal inflammation. We conclude that PUFA reduces the incidence of NEC and intestinal inflammation in a neonatal rat model. 相似文献
993.
Psychopathology and pediatric complex partial seizures: seizure-related, cognitive, and linguistic variables 总被引:6,自引:2,他引:4
PURPOSE: This study examined the role of cognition, language, seizure-related, and demographic variables in the psychopathology of children with complex partial seizure disorder (CPS) of average intelligence. METHODS: One-hundred one CPS and 102 normal children, aged 5.1 to 16.9 years, had a structured psychiatric interview and cognitive and language testing. Parents provided demographic, perinatal, and seizure-related information, as well as behavioral information through the Child Behavior Checklist (CBCL) and a structured psychiatric interview about the child. RESULTS: Significantly more CPS patients had psychopathology, cognitive deficits, and linguistic deficits than did those in the normal group. Among the patients, Verbal IQ predicted the presence of a psychiatric diagnosis, as well as CBCL scores in the borderline/clinical range. Seizure, linguistic, and demographic variables were unrelated to psychopathology. The cognitive and linguistic deficits of the CPS group, however, were predicted by seizure factors (e.g., prolonged seizures/febrile convulsions; seizure frequency/number of antiepileptic drugs) and demographic factors (e.g., minority status). CONCLUSIONS: Because subtle verbal cognitive deficits predict behavioral disturbances in pediatric CPSs, the study's findings highlight the importance of assessing behavior, cognition, and language in these children. They also underscore the negative impact of prolonged seizures, febrile convulsions, seizure frequency, and antiepileptic drug polytherapy on cognition and language in pediatric CPSs. 相似文献
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996.
Caplan LR 《Current treatment options in cardiovascular medicine》2004,6(3):217-222
Opinion statement Many patients develop confusion, lethargy, and cognitive and behavioral abnormalities during or after cardiac decompensation.
Congestive heart failure and the accompanying elevation in systemic venous pressure and decrease in cardiac output can lead
to changes within the cranial cavity that cause an encephalopathy. At times, excess cerebrospinal fluid accumulates within
the cranium causing an apathetic state identical to that seen in patients with other causes of hydrocephalus. Awareness of
the syndrome of cardiac encephalopathy and optimal management of congestive heart failure and body fluids can reverse the
neurologic dysfunction. In some patients with excess cerebrospinal fluid, lumbar puncture with removal of cerebrospinal fluid
can reverse the apathetic state. 相似文献
997.
BACKGROUND: The authors used the American Society of Anesthesiologists Closed Claims Project database to identify specific patterns of injury and legal liability associated with regional anesthesia. Because obstetrics represents a unique subset of patients, claims with neuraxial blockade were divided into obstetric and nonobstetric groups for comparison. METHODS: The American Society of Anesthesiologists Closed Claims Project is a structured evaluation of adverse anesthetic outcomes collected from closed anesthesia malpractice insurance claims of professional liability companies. An in-depth analysis of 1980-1999 regional anesthesia claims was performed with a subset comparison between obstetric and nonobstetric neuraxial anesthesia claims. RESULTS: Of the total 1,005 regional anesthesia claims, neuraxial blockade was used in 368 obstetric claims and 453 of 637 nonobstetric claims (71%). Damaging events in 51% of obstetric and 41% of nonobstetric neuraxial anesthesia claims were block related. Obstetrics had a higher proportion of neuraxial anesthesia claims with temporary and low-severity injuries (71%) compared with the nonobstetric group (38%; P 相似文献
998.
Porcine small intestine submucosa as a flexor tendon graft 总被引:9,自引:0,他引:9
Derwin K Androjna C Spencer E Safran O Bauer TW Hunt T Caplan A Iannotti J 《Clinical orthopaedics and related research》2004,(423):245-252
An attractive strategy for tendon tissue engineering is the use of natural extracellular matrices as scaffold materials. One matrix that has been shown to promote healing and regeneration of neotissue in various applications is porcine-derived small intestinal submucosa. It was the objective of this study to investigate small intestinal submucosa for intrasynovial flexor tendon grafting in a canine model. We hypothesized that at 6 weeks small intestinal submucosa grafts would undergo host cell infiltration, neovascularization, and replacement by host neotendon. We also hypothesized that small intestinal submucosa grafts would be incorporated by the host without extensive adhesions to surrounding tissues and therefore maintain normal digit function. An intrasynovial tendon autograft was used as a gold standard. At 6 weeks the intrasynovial tendon autografts remained viable, contained normal numbers of cells along their length, and had minimal peritendinous adhesions. Four of six autografts had normal function as determined by rotation of the distal interphalangeal joint. Also at 6 weeks, the small intestinal submucosa grafts had host cell infiltration, neovascularization, and wavy, oriented tissue. However, ubiquitous adhesions together with impaired function in all cases suggest that small intestinal submucosa grafts in the configuration used are not suitable as full-length intrasynovial grafts in this tendon and animal model. 相似文献
999.
1000.
Relationship between crown placement and the survival of endodontically treated teeth 总被引:8,自引:0,他引:8
STATEMENT OF PROBLEM: Crowns have been considered the restoration of choice for endodontically treated teeth, but their selection has been based primarily on anecdotal evidence. PURPOSE: This study tested the hypothesis that crown placement (coronal coverage) is associated with improved survival of endodontically treated teeth when preaccess, endodontic, and restorative factors are controlled. MATERIAL AND METHODS: A University of Iowa College of Dentistry treatment database was used to identify permanent teeth that had undergone initial obturation between July 1, 1985, and December 31, 1987. Study patients were restricted to persons with at least 1 dental visit in each 2-year interval from 1985 to 1996; a simple random sample of 280 patients (n = 400 teeth) was selected. Dental charts, radiographs, and computerized databases were examined to ascertain variables of interest and to verify study inclusion criteria. Kaplan-Meier survival estimates were generated for the 203 teeth that satisfied study inclusion criteria. Multivariate Cox proportional hazards regression models were developed, with standard errors adjusted to account for clustering of teeth within patients. RESULTS: When tooth type and radiographic evidence of caries at access were controlled, the final Cox model showed that endodontically treated teeth not crowned after obturation were lost at a 6.0 times greater rate than teeth crowned after obturation (95% confidence interval: 3.2 to 11.3). CONCLUSION: Within the limitations of this study, a strong association between crown placement and the survival of endodontically treated teeth was observed. These results may impact treatment planning if long-term tooth retention is the primary goal. 相似文献