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991.
Villarreal-Calderón A Acuña H Villarreal-Calderón J Garduño M Henríquez-Roldán CF Calderón-Garcidueñas L Valencia-Salazar G 《Archives of environmental health》2002,57(5):450-460
Strategies to promote lifelong physical activity among children are needed to stem the adverse health consequences of inactivity. However, the health effects in growing children of long-term exposure to a polluted atmosphere are of deep concern. The atmosphere of south Mexico City (SMC) is characterized by a complex mixture of air pollutants, including ozone, particulate matter, and aldehydes. Radiological evidence suggests that small-airway disease could be present in clinically healthy, tobacco unexposed SMC children. The aim of this study was to assess, by means of a self-reported questionnaire, the physical education class times, daily outdoor after-school exposure time, and tobacco exposure in students attending public elementary and middle schools in SMC. Additionally, the time each student spent viewing television was assessed, and the authors measured each student's weight and height to determine body mass index (BMI, weight in kg divided by height in m2). The survey included 1,159 students in grades 7-9. The authors identified 2 critical periods of outdoor exposure in SMC children that coincided with significant concentrations of both ozone and particulate matter with diameters less than 10 micrometers (PM10): during school time after 11:00 A.M. and in the after-school outdoor activity period, usually extending from 1:00 P.M. to 6:00 P.M. Thirty-two percent of elementary and 61% of middle school students have physical education classes after 11:00 A.M. Students in SMC spend an average of 19.6 hr/wk outdoors in the after-school period, during which time they are engaged in light to moderate physical activities. Half of the students are exposed to tobacco smoke at home, and 7% of middle school students smoke. On the basis of BMI, 60% of students were classified as undernourished, overweight, or obese. No correlations were found between BMI and time spent viewing TV, time outdoors (on weekdays and weekends), or exposure to environmental tobacco smoke. Children and adolescents in SMC are participating in physical activities that enhance multiple components of health-related fitness. However, their activities occur outdoors, where they are exposed to high concentrations of air pollutants throughout the year. The authors believe that SMC children and adolescents must be educated, through both the school and health systems, regarding ways to obtain the necessary exercise while protecting themselves from the high concentrations of pollutants. Individuals should instruct and encourage young people to be involved in lifetime fitness activities and to eat balanced diets, if the goal is to control health-care costs, reduce disease incidence, and improve the overall quality of life of the Mexico City population. 相似文献
992.
We undertook a retrospective analysis of epilepsy patients referred and treated for more than 6 months with the ketogenic diet during 1994-1999 at Connecticut Children's Medical Center. Outcome measures included antiepileptic drug number, seizure frequency, electroencephalogram background/paroxysmal activity, and adverse effects at 6 months and 1 year on the ketogenic diet. The final cohort included 24 of 48 referred patients (mean age, 6.5 years; range = 1-15 years of age). The etiology of epilepsy was equally divided between idiopathic and cryptogenic epilepsy and symptomatic epilepsy. Intention to treat analysis revealed that 35% (17 of 48) achieved more than 50% reduction in seizure frequency, and 8.5% (four of 48) were seizure-free by 6 months. A sustained 50% or greater reduction at 1 year was observed in 23% (11 of 48), and the same 8.5% (four of 48) remained seizure-free. None of these improvements were statistically related to age (P = 0.97), sex (P = 0.78), or epilepsy etiology (P = 0.80). The number of antiepileptic drugs used per patient decreased. Electroencephalogram at 1 year demonstrated an improvement in background in 31% (five of 16 patients) and a reduction in paroxysmal features in 37.5% (6 of 16 patients). Most adverse effects were mild, self-limited, and occurred early. Hyperuricemia (more than 6 mg/dL) was more persistent in three patients. 相似文献
993.
McAdam DB Zarcone JR Hellings J Napolitano DA Schroeder SR 《American journal of mental retardation : AJMR》2002,107(4):261-269
Consumer satisfaction and social validity were measured during a double-blind, placebo-controlled evaluation of the atypical neuroleptic risperidone in treating severe aberrant behavior of persons with developmental disabilities. First, a satisfaction survey was completed after a medication trial by each participant's caregiver. Results showed that 100% of the caregivers felt that participation was a positive experience for themselves and participants. Second, 52 community members viewed videotapes of 5 participants during a clinical interview when they were taking either placebo or risperidone. Raters also indicated that when on the medication, participants displayed fewer aberrant behaviors, were less irritable, in a better mood, and were more responsive to their environment. 相似文献
994.
Soto-Faraco S Lyons J Gazzaniga M Spence C Kingstone A 《Brain research. Cognitive brain research》2002,14(1):139-146
Integrating dynamic information across the senses is crucial to survival. However, most laboratory studies have only examined sensory integration for static events. Here we demonstrate that strong crossmodal integration can also occur for an emergent attribute of dynamic arrays, specifically the direction of apparent motion. The results of the present study show that the perceived direction of auditory apparent motion is strongly modulated by apparent motion in vision, and that both spatial and temporal factors play a significant role in this crossmodal effect. We also demonstrate that a split-brain patient who does not perceive visual apparent motion across the midline is immune to this audiovisual dynamic capture effect, highlighting the importance of motion being experienced in order for this new multisensory illusion to occur. 相似文献
995.
Michael A Kraut Sarah Kremen Lauren R Moo Jessica B Segal Vincent Calhoun John Hart 《Journal of cognitive neuroscience》2002,14(1):37-47
The human brain's representation of objects has been proposed to exist as a network of coactivated neural regions present in multiple cognitive systems. However, it is not known if there is a region specific to the process of activating an integrated object representation in semantic memory from multimodal feature stimuli (e.g., picture-word). A previous study using word-word feature pairs as stimulus input showed that the left thalamus is integrally involved in object activation (Kraut, Kremen, Segal, et al., this issue). In the present study, participants were presented picture-word pairs that are features of objects, with the task being to decide if together they "activated" an object not explicitly presented (e.g., picture of a candle and the word "icing" activate the internal representation of a "cake"). For picture-word pairs that combine to elicit an object, signal change was detected in the ventral temporo-occipital regions, pre-SMA, left primary somatomotor cortex, both caudate nuclei, and the dorsal thalami bilaterally. These findings suggest that the left thalamus is engaged for either picture or word stimuli, but the right thalamus appears to be involved when picture stimuli are also presented with words in semantic object activation tasks. The somatomotor signal changes are likely secondary to activation of the semantic object representations from multimodal visual stimuli. 相似文献
996.
Deuchert M Ruben J Schwiemann J Meyer R Thees S Krause T Blankenburg F Villringer K Kurth R Curio G Villringer A 《Neuroreport》2002,13(3):365-369
Cortical signal intensity changes due to brief (1 s) innocuous electrical stimuli applied to the second and fifth finger of the right hand were measured by means of fMRI at 1.5 T. The activation pattern in this event-related fMRI approach closely resembled that obtained in recent block-design studies. Activations were found in contralateral primary (SI) and bilaterally in secondary (SII) somato-sensory cortex as well as in posterior parietal cortex, insula, and supplementary motor area (SMA). In SI, the somatotopic organization of the hand area is demonstrated, more clearly to be seen in area 3b than in area 1 and 2. In conclusion, the feasibility to employ event-related somatosensory stimulation paradigms in fMRI studies is demonstrated. 相似文献
997.
The signaling adapter protein PINCH is up-regulated in the stroma of common cancers,notably at invasive edges 总被引:9,自引:0,他引:9
BACKGROUND: PINCH is an LIM (double zinc finger domain) protein that functions as an adapter at a key convergence point for integrin and growth factor signal transduction. Because no information is available regarding its expression in vivo in human tissues, this study evaluated the distribution and abundance of PINCH in patients with breast, prostate, lung, colon, and skin carcinomas. METHODS: A polyclonal antibody was raised to a purified 6-histidine PINCH fusion protein and used to evaluate 74 cases comprising 33 breast carcinomas (21 ductal carcinomas, 6 lobular carcinomas, 4 ductal carcinomas in situ, 2 lobular carcinomas in situ), 22 prostate carcinomas, 5 colon carcinomas, 6 lung carcinomas (3 adenocarcinomas and 3 squamous carcinomas), and 8 skin carcinomas (4 basal cell carcinomas and 4 squamous cell carcinomas) by immunoperoxidase histochemistry of formalin-fixed, paraffin-embedded tissues. Lysates of frozen tissue from the epithelium of two normal breasts and six breast carcinomas were evaluated by immunoblotting. RESULTS: Immunostaining for PINCH was increased in the cytoplasm of fibroblastoid cells in areas of the tumor-associated stroma in all carcinomatous tissues evaluated. The most intense stromal immunostaining for PINCH was noted at invasive edges, particularly in breast carcinomatous tissue. Immunoblotting of lysates from normal breast and breast carcinomatous tissue confirmed that PINCH protein expression was markedly increased in breast carcinomatous tissues. CONCLUSIONS: PINCH is up-regulated in tumor-associated stromal cells, particularly at invasive edges, and may be a marker for stroma manifesting the ability to facilitate invasion. Because of this and because PINCH functions as a "molecular switch" in signal transduction, PINCH may be a new target for drug discovery aimed at the tumor-associated stroma. 相似文献
998.
999.
The Utility of External Beam Radiation and Intracystic 32 P Radiation in the Treatment of Craniopharyngiomas 总被引:2,自引:0,他引:2
Schefter JK Allen G Cmelak AJ Johnson M Toms S Duggan D Blevins LS 《Journal of neuro-oncology》2002,56(1):69-78
Background. The management of craniopharyngiomas has historically been controversial in terms of the extent of initial surgical resection and the use of additional treatments. Various options include radical excision versus a more conservative surgical approach followed by external beam radiation; most recently, intracystic 32
P radiation has been used in selected patients.
Methods. We reviewed our experience with 25 patients with craniopharyngiomas treated between 1984 and 1999 to assess the effectiveness of external beam radiation and intracystic 32
P radiation therapy in preventing progression and recurrence of local disease.
Results. All patients underwent surgery as a component of initial therapy for their histologically-proven craniopharyngiomas. Fifteen patients additionally received external beam radiation. Forty-five percent of patients who underwent incomplete resections followed by external beam radiation required additional therapy. In contrast, 80% of patients who had incomplete resections without post-operative external beam radiation required further treatment. Seven patients had intracystic 32
P colloid injections. Neither of the two patients receiving 32
P intracystic radiation as part of their initial therapy needed further treatment. Only one of the five patients receiving 32
P intracavitary radiation for disease progression following initial therapy required further intervention. Of the remaining four patients, three enjoyed responses to treatment and one had stable disease.
Conclusions. Our observations support the use of external beam radiation for prevention of tumor progression in adults unable to receive a complete surgical resection. Our results additionally suggest that intracystic 32
P radiation results in control of cystic components of craniopharyngiomas in the majority of cases. 相似文献
1000.
In the last few years, three new herpesviruses, HHV-6, -7 and -8, have been discovered, which share interesting biological characteristics for a possible role in the development of both neurological and lymphoproliferative diseases. In particular HHV-8, besides being strongly associated with Kaposi's sarcoma, is related with several lymphoproliferative diseases. More recently, specific viral sequences belonging to HHV-8 have been detected in autoptic brain specimens from multiple sclerosis patients and controls, suggesting that, similarly to HHV-6, this novel herpesvirus is strongly neurotropic. HHV-8 is an unusual herpesvirus in that it is able to produce homologues of several human gene products, resulting in alterations in cell cycle, in apoptosis and cell-mediated immune responses. To verify a possible relationship between HHV-8 and the development of amyotrophic lateral sclerosis (ALS), we investigated the presence of signs of HHV-8 infection, by both nested polymerase chain reaction (nPCR) and indirect immune fluorescence analysis in ALS patients. Both PCR and serological data did not suggest a clear role of this virus in originating ALS. Nevertheless, new insights into the mechanisms by which viruses may interact with the host cell genome and with the human immune system make the viral hypothesis of ALS still worthy of further studies. 相似文献