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951.
952.
This study investigated the influence of attention on the sensory integration component of postural control in young and older adults. Eighteen young and 18 older healthy subjects performed information-processing tasks during different postural challenge conditions. Postural conditions included seated, standing on a firm surface, standing on a sway-referenced floor, and standing on a sway-referenced floor while viewing a sway-referenced scene. During each condition, reaction time (RT) was measured during two simple and one inhibitory RT tasks. For the inhibitory task, the time required to inhibit an action was derived, termed the inhibitory time (IT). Performing a RT task was associated with increased postural sway in older subjects, but not in young subjects. The greatest influence of RT task on sway of older subjects was found during the sway-referenced floor/sway-referenced scene condition. Conversely, postural condition had an influence on RT task performance in both young and older subjects. The IT was increased in both young and older subjects only during the sway-referenced floor/scene condition. These results suggest that the sensory integration component of postural control in particular seems to require attention. Further, our data suggest that attentional processes related to inhibitory control are engaged when sensory integration requirements are high. 相似文献
953.
954.
Lopoo JB Paek BW Maichin GA Lipshutz GS Jennings RW Farmer DL Sandberg PL Feldstein VA Filly RA Farrell JA Harrison MR Albanese CT 《Fetal diagnosis and therapy》2000,15(3):177-179
Placental vascular communications can present a life-threatening problem in monochorionic twins when one fetus has a lethal anomaly. Although selective feticide is the best option for salvaging the normal twin, techniques normally employed (i.e. intracardiac potassium, air embolism) are not prudent given the common circulatory system. Furthermore, in monoamniotic, monochorionic twin gestations it is important to transect the umbilical cord completely to prevent entanglement of the dead fetus around the cord of the normal twin. We present two cases of monochorionic twins in which the cords were transected with a harmonic scalpel under ultrasonic guidance via one trocar. The harmonic scalpel is an instrument which can simultaneously coagulate and cut blood vessels or tissues. The cord ultrasonic transection procedure is a novel, minimally invasive technique which offers several advantages over the methods currently used for selective feticide in discordant monochorionic twin gestations. 相似文献
955.
The potential of mitotane (ortho, para'-DDD, commonly used to treat adrenal carcinomas in humans and dogs) was investigated as an alternative to surgical adrenalectomy in birds, salamanders, and lizards. House sparrows (Passer domesticus) were injected twice daily with vehicle or one of two doses of mitotane (225 or 450 mg/kg), and basal and stress-induced levels of corticosterone (CORT) were measured 3 and 5 days after injections. Mitotane reduced basal CORT levels to nondetectable and abolished stress-induced CORT increases by the 3rd day of treatment. In another study, a single injection of mitotane was effective in lowering endogenous CORT levels 36 h later, but levels had apparently recovered by 10 days after the injection. Mitotane did not effect testicular weights and had no detectable effect on testosterone levels. In contrast to its effects on house sparrows, mitotane did not lower endogenous CORT levels in either tiger salamanders (Ambystoma tigrinum) or tree lizards (Urosaurus ornatus), even at doses much higher than those used in house sparrows. 相似文献
956.
The effects of chronic absence of active nasal respiration on the growth of the skull: A pilot study 总被引:2,自引:0,他引:2
Willis L. Schlenker DDS MS Bryan D. Jennings DDS MS M.Toufic Jeiroudi DDS MS Joseph M. Caruso DDS MS MPH 《American journal of orthodontics and dentofacial orthopedics》2000,117(6):706-713
Oral respiration associated with an obstructed nasal airway is common in orthodontic patients. For several years chronic oral respiration has been implicated as a prime causative factor in the development of "adenoid facies or the "long-face syndrome. The animal experiment reported here begins a series designed to study, as separate variables, the 2 components of chronic oral respiration: (1) chronic absence of active nasal respiration and 2) chronic mouth opening to find out what dentofacial changes can be attributed to chronic absence of active nasal respiration alone. In this pilot study, 5 growing dogs underwent tracheotomy so that significant active nasal respiration was not possible and oral respiration was not essential. 相似文献
957.
Victoria E. Rey Caballero Manuel Urbaneja LópezJosé L. García Benítez Dahlia Quijada To Ong 《Progresos de Obstetricia y Ginecología》2008
Cerebral venous sinus thrombosis is uncommon. Pregnancy is a major risk factor for the development of this entity. We report the case of a patient with Job’s syndrome and protein C and S deficiency who developed cerebral venous sinus thrombosis and dural fistula at 36 weeks’ gestation. After heparinization, the treatment of choice, pregnancy termination to eliminate the prothrombotic status and embolization of the dural fistula were required to obtain complete remission of the neurological symptoms. 相似文献
958.
Carey Jackson J Taylor VM Chitnarong K Mahloch J Fischer M Sam R Seng P 《Journal of community health》2000,25(5):359-375
Southeast Asian immigrants have lower levels of Pap testing than any other racial/ethnic group in the US, and are particularly unfamiliar with western culture and biomedical concepts of prevention. We completed an ethnographic study (N = 42) focusing on cervical cancer screening among Cambodian American women. We also conducted a community-based survey (N = 413) to examine the generalizability of our qualitative results. This report summarizes the results, and describes how we used our findings to influence the content of a multifaceted intervention program targeting Cambodian immigrants. The following constructs were found to be barriers to cervical cancer control: a traditional orientation to the prevention, causation, and treatment of disease; lack of familiarity with western early detection concepts; low levels of knowledge about cervical cancer; concerns about the Pap testing procedure; and health care access issues. In general, the quantitative results confirmed our ethnographic findings. The intervention program, which is delivered by bicultural outreach workers, includes home visits, presentations at small group meetings, barrier-specific counseling, use of a Khmer-language video, and tailored logistic assistance (e.g., transportation and medical interpretation). Both the video and presentation provide cultural context while simultaneously addressing multiple barriers to screening (e.g., women's fear of surgery and preference for female providers). Outreach workers are trained to counsel women about 10 potential barriers including avoidance of biomedicine, perceptions that gynecologic exams are embarrassing, and lack of English proficiency. Our results reinforce the importance of considering health problems within the context of a population's traditional belief systems and daily routines. 相似文献
959.
Cynthia M. Austin Sandra P. Stewart James M. Goldfarb Leon A. Sheean Victoria R. Gindlesperger Method A. Duchon 《Journal of assisted reproduction and genetics》1996,13(7):540-545
Purpose: Our purpose was to assess how the number of embryos transferred can be adjusted to limit multiple gestations.
Methods: A retrospective analysis of 535 consecutive embryo transfers for the years 1991–1993 was conducted.
Results: Fewer than three embryos were associated with a low pregnancy rate. Pregnancy rates were highest in women less than 35 when four or more embryos were transferred. With four or more embryos, multiple gestation pregnancy correlated with the number of high-quality embryos transferred. The risk of triplets and quadruplets was greatest for women less than 40.
Conclusions: Multiple-embryo transfer carries a risk of plural gestation. The risk of multiple pregnancy cannot be eliminated without decreasing the pregnancy rate. The risk of high-order multiple pregnancy was best correlated with the number of good-quality embryos transferred. While all are at risk, patients younger than 40 were at highest risk. 相似文献
960.
Victoria Romanus ers Fasth Paul Tordai Bengt Erik Wiholm 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S385):1043-1052
A retrospective analysis of the adverse reactions reported between 1979 and 1991, in the 139000 children under six years of age vaccinated in Sweden with the Danish BCG vaccine, strain Copenhagen 1331, showed an incidence of I.9 per 1000 vaccinated children. Regional lymphoglandular swellings and/or abscesses were most commonly reported in 1.4 per 1000. Serious, disseminated, BCG infections developed in four infants vaccinated neonatally. Three of the infants suffered from severe, combined, immunodeficiency syndrome, undiagnosed at the time of vaccination. The incidence of severe, combined, immunodeficiency syndrome was higher in the BCG-vaccinated population (4 per 100000 infants vaccinated within a year of their births), compared with all newborns in Sweden (1 per 100 000). The mean age at the onset of symptoms was 2.4 months for the seven non-BCG-vaccinated infants versus 1.3 months for the four BCG-vaccinated ones, while the immunodeficiency syndrome was diagnosed at an average age of 7.6 months in those who were not vaccinatedversus 5.3 months in those BCG-vaccinated. It is recommended that the selective BCG vaccination of infants at high risk of exposure to tuberculosis should be postponed to six months of age to reduce the risk of inoculating infants suffering from immunodeficiency syndromes. 相似文献