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21.
BACKGROUND: Production of grammatical morphology is typically impaired in agrammatic aphasic individuals, as is their capacity to produce the syntactic structure responsible for licensing that morphology. Whether these two impairments are causally related has been an issue of long-standing debate. If morphological deficits are a side-effect of underlying syntactic ones, as has been claimed (Friedmann & Grodzinsky, 1997; Izvorski & Ullman, 1999), therapy which improves the syntactic deficit should remediate the morphological deficit as well. This paper reports a case study of one individual with such co-occurring impairments and describes their recovery in response to linguistically-motivated treatment targeting his syntactic deficits. METHODS #ENTITYSTARTX00026; PROCEDURES: MD is a 56 year-old male diagnosed with non-fluent Broca's aphasia subsequent to a left-hemisphere CVA, with limited capacity to produce syntactically complex utterances and grammatical morphology. He was enrolled in therapy using Treatment of Underlying Forms (TUF; Thompson & Shapiro, 2005), targeting production of sentences involving Wh-movement (object relative clauses). MD participated in twice-weekly treatment sessions for approximately two months, with daily probes assessing his production of treated and untreated sentence types. In addition, probes assessing his grammatical morphology and sentence production were administered pre- and post-treatment. OUTCOMES #ENTITYSTARTX00026; RESULTS: Pre-treatment scores in tests of grammatical morphology and sentence production indicated deficits in both domains. During treatment, MD successfully acquired production of a variety of sentence with Wh-movement, though this did not generalize to sentences involving a grammatically distinct movement operation (NP-movement). Post-treatment scores also indicated a lack of improvement in production of grammatical morphology. CONCLUSIONS: The dissociation between MD's morphological and syntactic recovery indicates that the recovery of syntactic and morphological processes in aphasia may occur independently. This result is thus surprising under approaches in which morphological and syntactic impairments are strongly and causally related in aphasia, such as the Tree-Pruning Hypothesis (Friedmann, 2001; Friedmann & Grodzinsky, 1997). Further, these results reinforce the conclusion that aphasia treatment can lead to generalization, but only to linguistic material which is in a subset relation to trained structures (Thompson, Shapiro, Kiran & Sobecks, 2003). 相似文献
22.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献
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24.
Many different strategies are used to recruit students into scientific research careers, including neuroscience research. These strategies are rarely based on knowledge about students; instead, activities are selected based on their ease of implementation. The goal of the LEARN Project is to encourage high school students into mental health science research using the theme of learning and memory. One intervention the authors developed is five Web-based biographies introducing students to contemporary neuroscientist role models studying learning and memory. To guide the design of this intervention, the authors created a survey to determine where students obtain career information and who and what influences their career selection. In a convenience sample of 124 students, the authors found that almost all students use the Internet for information about careers, in addition to consulting family members and teachers. Students' career selections are influenced most by family members, teachers, and people already in the field. The most important factors students look for in their future career are money, fun, and a good match between current interests and future careers. The data affirm the value of outreach efforts that go beyond students to include a broader audience of parents and teachers who play a critical role in career selection. 相似文献
25.
26.
Estil Y. Strawn Jr. MD Miles J. Novy MD Kenneth A. Burry MD Cynthia L. Bethea PhD 《American journal of obstetrics and gynecology》1995,172(6):1837-1844
Objective: Our purpose was to determine whether insulin-like growth factors I and II preferentially stimulate uterine leiomyoma cells versus myometrial cells in monolayer culture.Study design: Leiomyomas and normal myometrium were obtained at hysterectomy from five premenopausal women. Specimens were enzymatically digested for use in primary monolayer cell cultures. By use of serum-free media, insulin-like growth factor I or II was added in 1, 10, and 100 ng/ml concentrations to both cell types with the patient serving as her own control. Cell number, prolactin production, and proliferative index values were measured on day 15 of cell culture.Results: Significant increases in cell number were found in the leiomyoma cultures (p < 0.05) treated with 10 and 100 ng/ml insulin-like growth factors I but not with insulin-like growth factos II. Neither factor exerted a stimulatory effect on myometrial cells.Conclusion: Insulin-like growth factor sI preferentially stimulates leiomyoma cells in monolayer culture. These results suggest an autocrine-paracine role in vivo for this factor in conjuction with gonadal steroids in promoting leiomyoma growth. 相似文献
27.
CONTEXT: The limited information available on the oral health status of rural children in the United States makes it difficult to devise policy strategies to address perceived problems. PURPOSE: To document the oral health status and dental care utilization of US children by place of residence, METHODS: Data from National Health Interview Surveys for 1995, 1997, and 1998, and from the third National Health and Nutrition Examination Survey (1988-1994) were analyzed. FINDINGS: Children residing in rural areas were more likely to be uninsured for dental care than were children from urban areas (41.1% versus 34.7%). A greater percentage of rural than urban children reported unmet dental needs (7.5% versus 5.6%); there was no difference in self-reported poor dental status. Urban children were more likely than rural children to have visited the dentist in the past year (73.6% versus 69.9%) and were also more likely to be regular users of dental care (61.7% versus 51.4%). Differences in percentage of rural and urban children with caries lesions and caries experience were not significant. CONCLUSIONS: Children residing in rural areas have less access to and utilization of dental care compared to children residing in urban areas. Moreover, poor rural children display less utilization of dental services than poor urban children. Differences in the sum of decayed and filled primary teeth and the sum of decayed, missing, and filled permanent teeth were not significant. 相似文献
28.
Cynthia J. Berg Jelka Zupan Philip J. d'Almada† Muin J. Khoury Lisa J. Fuller† ‡ 《Paediatric and perinatal epidemiology》1994,8(1):53-61
Summary. Very low birthweight (VLBW) is a commonly used endpoint in perinatal epidemiology, but the population of VLBW infants comprises a wide range of gestational ages and rates of fetal growth. We used data from a population-based study of all 1072 black and white VLBW liveborn infants born in 29 counties in Georgia between April 1986 and March 1988. Less than 1% of the VLBW infants were ≥ 37 weeks gestation; most were 29–32 weeks (26%) or 25 to 28 weeks (40%); 12% were 22 weeks or less. All infants 33 weeks gestation or greater were growth retarded. The population of VLBW infants seems to comprise three groups: approximately 11% very immature infants of 22 weeks or less; the majority of infants, born between 23 and 30 weeks, 90% of which are of normal weight for their gestational age; and a group of less premature, growth-retarded infants from 31 to 36 weeks. We found little or no difference in the distribution of gestational age or the percentage of intrauterine growth rates (IUGR) between black and white infants. In the USA the VLBW rate among black infants is over three times greater than that among white infants and consequently the rates of the three types of VLBW among black infants are likely to be triple those among white infants. 相似文献
29.
Sheana Salyers Bull Cynthia Gillette Russell E Glasgow Paul Estabrooks 《Health education & behavior》2003,30(5):537-549
Information on external validity of work site health promotion research is essential to translate research findings to practice. The authors provide a literature review of work site health behavior interventions. Using the RE-AIM framework, they summarize characteristics and results of these studies to document reporting of intervention reach, adoption, implementation, and maintenance. The authors reviewed a total of 24 publications from 11 leading health behavior journals. They found that participation rates among eligible employees were reported in 87.5% of studies; only 25% of studies reported on intervention adoption. Data on characteristics of participants versus nonparticipants were reported in fewer than 10% of studies. Implementation data were reported in 12.5% of the studies. Only 8% of studies reported any type of maintenance data. Stronger emphasis is needed on representativeness of employees, work site settings studied, and longer term results. Examples of how this can be done are provided. 相似文献
30.
David J Schretlen Cynthia A Munro James C Anthony Godfrey D Pearlson 《Journal of the International Neuropsychological Society》2003,9(6):864-870
Neuropsychologists often diagnose cerebral dysfunction based, in part, on marked variation in an individual's cognitive test performance. However, little is known about what constitutes the normal range of intraindividual variation. In this study, after excluding 54 individuals with significant health problems, we derived 32 z-transformed scores from 15 tests administered to 197 adult participants in a study of normal aging. The difference between each person's highest and lowest scores was computed to assess his or her maximum discrepancy (MD). The resulting MD values ranged from 1.6 to 6.1 meaning that the smallest MD shown by any person was 1.6 standard deviations (SDs) and the largest MD shown by any person was 6.1 SDs. Sixty-six percent of participants produced MD values that exceeded 3 SDs. Eliminating each person's highest and lowest test scores decreased their MDs, but 27% of the participants still produced MD values exceeding 3. Although MD values appeared to increase with age, adjusting test scores for age, which is standard in clinical practice, did not correct for this. These data reveal that marked intraindividual variability is very common in normal adults, and underscore the need to base diagnostic inferences on clinically recognizable patterns rather than psychometric variability alone. 相似文献