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121.
The present study evaluated the hypothesis (Mayeux et al., 1980) that visual confrontation naming deficits may underlie the memory complaint in patients with temporal lobe epilepsy (TLE). Thirty-nine patients with medically refractory left (n = 23) and right (n = 16) TLE were compared with an epilepsy control group with idiopathic primary generalized epilepsy (n = 38). All subjects completed selected subtests of the Multilingual Aphasia Examination and Wechsler Memory Scale (Form 1) together with a measure specifically designed for quantification of the memory complaint in TLE. Objective verbal memory test performance, confrontation naming, repetition, and comprehension were unrelated to memory self-report. Controlled Oral Word Association was the only measure to exert an influence on memory self-ratings, and this relationship was specific to the TLE group. The hypothesis of Mayeux et al. (1980) was not specifically supported, but the present findings do suggest that cognitive processes reflected in orthographically based and internally generated word retrieval play a role in memory self-report.  相似文献   
122.
Maze performance and morphology of frontal cortex were assessed in young adult, middle-aged, and aged rats with and without lesions of the nucleus basalis magnocellularis. Although maze performance did not vary with age, neuron number and the thickness of superficial laminae were reduced in aged rats. Lamina II-III neurons were hypertrophied in middle-aged rats relative to both younger and older groups. At all ages, lesions significantly impaired maze performance. In young adult rats, lesions moderately reduced the size of lamina II-III neurons. This effect was more pronounced in middle-aged rats. Lesions in aged rats did not affect neuron size. The neuronal changes seen in middle-aged rats may reflect a compensatory response to the expression of other age-related neuronal changes, which may affect the ability of cortical neurons to respond to lesion-induced loss of cholinergic input.  相似文献   
123.
The high rate of posttraumatic stress disorder (PTSD) among substance use disorder (SUD) patients has been documented in research protocols, but there is evidence that it is markedly under-diagnosed in clinical settings. To address the need for a brief self-report measure to identify SUD patients who may benefit from further assessment and/or treatment for PTSD, the psychometric properties of a modified version of the PTSD Symptom Scale Self-Report (PSS-SR) were examined in a treatment-seeking SUD sample (N = 118). The modified version of the PSS-SR, which measures both frequency and severity of PTSD symptoms, demonstrated good internal consistency reliability and was correlated with other self-report measures of trauma-related symptomatology. Comparisons between a structured PTSD diagnostic interview and the modified PSS-SR indicated that 89% of the PTSD positive patients were correctly classified by the modified PSS-SR. The clinical relevance of these findings was discussed.  相似文献   
124.
BACKGROUND: The aim of this study was to determine the mechanism by which the calcium channel promoter BAY y 5959 affects the control of heart rate and baroreflex sensitivity in conscious dogs with pacing-induced heart failure (HF). METHODS AND RESULTS: We compared responses to BAY y 5959, which increases inotropy and decreases chronotropy, with those to norepinephrine (NE), which coincidentally exerts the same directional effects on inotropy and chronotropy, albeit through different mechanisms, in the presence and absence of ganglionic blockade both in control and in HF. Both BAY y 5959 and NE elicit direct effects on the heart and indirect effects through activation of reflexes, primarily the sinoaortic baroreceptor reflex. BAY y 5959 still reduced heart rate in dogs with arterial baroreceptor denervation, but not after ganglionic blockade. HF induced classic catecholamine desensitization to the inotropic effects of NE and blunted reflex bradycardia. In contrast, inotropic responses to BAY y 5959 were preserved in HF. Surprisingly, the autonomically mediated bradycardia induced by BAY y 5959 was also preserved in HF. Baroreflex sensitivity was assessed in control and in HF by pulse interval-systolic arterial blood pressure (PI/SAP) slopes constructed in response to pharmacological alterations in arterial pressure. HF depressed the PI/SAP slope from 11.5+/-1.3 to 4.8+/-0.9 ms/mm Hg, but during BAY y 5959 infusion in HF, the PI/SAP slope was restored to 24.1+/-5.2 ms/mm Hg. To assess central versus peripheral actions of BAY y 5959, the agent was infused with intra-carotid artery perfusion at a low dose, which acted centrally but did not have an effect peripherally. Under these conditions, it still decreased heart rate and restored baroreflex sensitivity (PI/SAP slope, 12.7+/-2.8 ms/mm Hg). CONCLUSIONS: Thus, the calcium promoter restores arterial baroreflex sensitivity in HF. Based on intra-carotid artery experiments, this occurs through a central nervous system and vagal mechanism.  相似文献   
125.
The change in vascular smooth muscle cells (SMC) from a differentiated to a dedifferentiated state is the critical phenotypic response that promotes occlusive arteriosclerotic disease. Despite its importance, research into molecular mechanisms regulating smooth muscle differentiation has been hindered by the lack of an in vitro cell differentiation system. We identified culture conditions that promote efficient differentiation of Monc-1 pluripotent neural crest cells into SMC. Exclusive Monc-1 to SMC differentiation was indicated by cellular morphology and time-dependent induction of the SMC markers smooth muscle alpha-actin, smooth muscle myosin heavy chain, calponin, SM22alpha, and APEG-1. The activity of the SM22alpha promoter was low in Monc-1 cells. Differentiation of these cells into SMC caused a 20-30-fold increase in the activity of the wild-type SM22alpha promoter and that of a hybrid promoter containing three copies of the CArG element. By gel mobility shift analysis, we identified new DNA-protein complexes in nuclear extracts prepared from differentiated Monc-1 cells. One of the new complexes contained serum response factor. This Monc-1 to SMC model should facilitate the identification of nodal regulators of smooth muscle development and differentiation.  相似文献   
126.
A continual supply of the amino acid glutamine (GLN) may be necessary for cancerous cell growth. GLN plays a central role in multiple metabolic pathways and has long been considered an essential component of tissue culture media. However, the GLN requirements of tumor cell lines and the factors that determine a cell's need for GLN have not been comprehensively studied. Also, it remains unclear how various metabolic pathways contribute to GLN consumption. In the present study, possible determinants of GLN metabolism were examined in seven breast cell lines, two derived from immortalized normal tissue and five of tumor origin. These cells exhibited different dependencies on media GLN concentration for growth and a wide range of GLN utilization rates. GLN uptake was facilitated by a single, common transporter functionally defined as System ASC. However, the affinities for GLN exhibited by this transporter differed appreciably between cell lines. Furthermore, the concentration at which media GLN became a limiting factor for cellular proliferation correlated with transporter affinity. The origin of the cell lines was not a determinant of GLN metabolism because immortalized cells of nontumor origin exhibited GLN dependence and utilization rates comparable to those of tumor-derived cells. The rates of CO2 production from GLN were similar for each cell lines. Rates of GLN disappearance and glutamate appearance in media were strongly correlated, with 32-80% of media GLN converted to glutamate. Both rates were directly affected by media cystine concentration, suggesting that a large portion of glutamate efflux was coupled with cystine import through the amino acid transport system x(c)-. These results demonstrated that cell growth is a function of GLN influx and suggest that GLN is used to supply glutamate and cystine, perhaps for glutathione synthesis.  相似文献   
127.
It is the purpose of this study to compare the prognostic value of the Herring classification (lateral pillar) with that of the Catterall classification. The material is constituted by 45 patients affected with Perthes' disease and reviewed an average of 24 years after onset. At follow-up the hips were divided into three classes based on joint congruency as suggested by Stulberg. The Catterall classification demonstrated overall a better predictive value for the Herring system. Instead, the most satisfactory reproducibility seems to be that of Herring: 80% as compared to 42% for the Catterall classification.  相似文献   
128.
A multiple case study design was used to explore the practice of health education in acute care settings in Hong Kong. Two case studies, a medical ward and a surgical ward, were selected to reflect the real setting in which nurses carry out health education in acute care. Data collection methods involved the use of non-participant observation and semi-structured interviews. Seven nurses and eight patients were interviewed to explore their understanding of health education concepts, the use made in the wards of health education and the factors influencing such practice in the acute settings. Individual and cross-case analysis showed that respondents' understanding of the concept of health education was limited to patient information-giving. Although the importance of health education in acute patient care was acknowledged, the degree to which health education featured in nurses' practice was minimal. Many available opportunities for health education were missed and factors such as nurses' busy-ness and the associated lack of time and staff were identified as influencing health education practice in these acute care settings. Implications for practice and future studies were discussed in the light of these findings.  相似文献   
129.
130.
The nucleotide sequence of luxD (EMBL accession No. X65611), encoding acyltransferase (ACT), of the lux operon from Photobacterium leiognathi PL741 was determined, and the amino acid (aa) sequence was deduced. ACT is a component of the fatty acid reductase complex, which is responsible for converting fatty acid to aldehyde that serves as the substrate in the luciferase-catalyzed bioluminescent reactions. The protein has a calculated M(r) of 34,384 and comprises 305 aa residues. Alignment and comparison of the ACT of P. leiognathi with that of Vibrio fischeri ATCC7744, V. harveyi B392 and Xenorhabdus luminescens Hm shows that there is 66%, 59% and 61% aa identity, respectively.  相似文献   
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