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91.
目的 评价2019年广东省不同地市(除中山市)的公共卫生资源配置状况。方法 从《2019年广东省卫生健康统计年鉴》中选取专业公共卫生机构数、专业公共卫生机构床位数、专业公共卫生机构执业(助理) 医师数、专业公共卫生机构注册护士数和每万人口公共卫生人数五个评价指标,利用加权秩和比法综合评价广东省不同地市的公共卫生资源配置差异。结果 WRSR与Probit的回归方程为[AKY^5]=0.250Probit-0.745(F=362.461,P<0.05,R=0.980);将不同地市公共卫生资源配置分为四档,肇庆市、广州市、佛山市、深圳市四市公共卫生资源配置处于较高水平,则汕尾市、潮州市则较为落后。结论 广东省公共卫生资源整体上逐年提升,但每万人口公共卫生人数与目标相比还具有差距;不同地区间公共卫生资源配置差异大,人均获得资源不均衡。  相似文献   
92.
多通道人工耳蜗在语前聋儿童及青少年中的应用   总被引:4,自引:0,他引:4  
目的 通过对植入人工耳蜗的语前聋儿童和青少年的听力和语言能力的评估 ,探讨我国儿童在使用人工耳蜗后的听力和言语能力发展规律及影响因素。方法  2 5例行人工耳蜗植入的语前聋儿童及青少年患者参与本组测试。选用《聋儿听觉言语康复评估方法》作为测试材料 ,分别进行声音、言语声和环境声的辨别 ,数词、单字词、双字词、3字词、韵母、声母、声调、封闭项列短句的识别 ,开放项列字词和开放项列短句识别 ,语言清晰度 ,模仿句长 ,听话识图和看图说话等方面测试。结果 受试者术后均能感知到声音 ,辨别不同类别的声音。封闭项列测试结果全部大于机会水平 ,正确识别率随人工耳蜗使用时间而不断增加 ,随植入时年龄的增长而呈下降趋势。术后约半年显现开放项列识别能力 ,使用人工耳蜗后对患儿的言语发育具有较大帮助。结论 尽早对语前聋患儿植入人工耳蜗及进行术后康复 ,以达改善听力 ,提高语言能力 ,促进身心全面发展的目的。  相似文献   
93.
Localized brain activation in response to moving visual stimuli was studied by functional magnetic resonance imaging (fMRI). Stimuli were 100 small white dots randomly arranged on a visual display. During the Motion condition, the dots moved along random, noncoherent linear trajectories at different velocities. During the Blink condition, the dots remained stationary but blinked on and off every 500 ms. The Motion and Blink conditions continuously alternated with 10 cycles per run and 6–8 runs per experiment. In half of the runs, the starting stimulus condition was Motion, while in the remaining runs it was Blink. A series of 128 gradient echo echoplanar images were acquired from 5–7 slices during each run using a 1.5 T GE Signa with an Advanced NMR echoplanar subsystem. The time series for each voxel were analyzed in the frequency domain. Voxels which demonstrated a significant spectral peak at the alternation frequency and whose phase changed in response to stimulus order were considered activated. These activated voxels were displayed upon high resolution anatomical images to determine the sites of activation and were also transformed into the coordinates of Talairach and Tournoux ([1988] Co-planar Stereotaxic Atlas of the Human Brain, New York: Thieme) for comparison to prior neuroimaging studies. Seven of ten subjects showed clusters of activation bilaterally at the junction of the temporal and occipital lobes (area 37) in response to moving stimuli. Most activated voxels were located within or adjacent to a region designated the parietal-temporal-occipital fossa, or PTOF. Five subjects also showed activation to moving stimuli in midline occipital cortex. The activated voxels in midline cortex had a significantly shorter phase delay in their MR signal change relative to voxels in PTOF. © 1995 Wiley-Liss, Inc. 1
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America
  •   相似文献   
    94.
    Ehrenberg’s Law-like relationship between height and weight [log was applied to a group of public school and Govt. school children in New Delhi. It was found that the model log was comparatively a good fit for public school children and the model log for Govt. school children. On fitting the model to the sample data it was found that the value of ‘a’ was 0.8, with some minor variation in the second decimal point and the value of ‘b’ was 0.39 & 0.36 respectively for public school boys and girls and 0.32 & 0.29 respectively for Govt. school boys & girls. These results corroborates with the findings of the earlier studies that the intercept constant ‘b’ in the Law-like relationship equation is influenced by the nutrition of children. This model is recommended because of its simplicity and practical usefulness using only already available information.  相似文献   
    95.
    IntroductionAt extremely low gestational ages, preterm infants are markedly physiologically immature, thus their responses to common clinical interventions may differ from more mature preterm babies. This study was performed to describe the evidence base which is available to make care decisions for such infants.MethodsA literature search of recent large neonatal randomized controlled trials (RCTs) was performed to determine the representation of infants <25 weeks of gestation, and whether it is clear if the overall results applied to the most immature infants.ResultsAmong 30 multi-centre RCTs in neonatology from the last 5 years, many excluded the most immature infants, and those that included them rarely presented the impacts of the intervention on the most at-risk group. Over 25,000 infants of under 32 weeks gestational age (GA) were included in these trials. Eight trials presented results of the primary outcome for infants of <26 weeks GA (n = 2,152) and a further four trials for infants <25 weeks, n = 711.ConclusionThe evidence base for treatment decisions for the highest risk infants in the NICU is severely limited. RCTs in extremely preterm infants should not exclude the highest risk group, and lower limits of gestational age (or body weight) should be avoided, any infant receiving intensive care should be eligible regardless of how immature. The results among the most immature infants should be presented separately, or be easily available, in order to build a database of effective treatments among infants of 22,23, and 24 weeks GA.  相似文献   
    96.
    为了解分泌性中耳炎( O M E)对内耳听觉功能的影响,对 O M E220 例、304 耳分别进行纯音测听及声阻抗测定。结果表明,部分 O M E 患者骨导听阈升高,除造成传音性耳聋外,合并感音性耳聋( S N H L)为318% ,并随着病程延长, S N H L 发病率增高。提示应积极有效地治疗本病,应用扩血管及营养神经药物可防治 S N H L的发生。  相似文献   
    97.
    Body growth was studied in 32 subjects with vesicoureteric reflux (VUR), diagnosed following the prenatal finding of urinary tract dilatation, who had normal renal filtration function and who received antibacterial prophylaxis by the first few days of life. They were followed for 1–5 years (mean 2.3 years). Most had persistent VUR during the 1st year of life. Body growth performance was compared with that of 94 subjects with VUR diagnosed and treated by us after the neonatal period. During the follow-up period, none of the patients with prenatally detected VUR had a height Z score below –2, nor a weight-for-height index below 90%, and 1 had variations in height Z score ≥1. The difference in the percentage of patients with prenatally detected VUR (1/32) and those with VUR diagnosed and treated after the neonatal period (20/94) who had variations in height Z score ≥1 was significant (P=0.035). Patients with prenatally detected VUR and normal renal filtration function, given antibacterial prophylaxis by the first few days of life, have normal body growth, although VUR still persists. Received: 19 March 1998 / Revised: 10 February 1999 / Accepted: 10 February 1999  相似文献   
    98.
    Overnight urines were collected each month for 12–16 months from 321 normal subjects at 19 medical centers in 14 countries distributed on 5 continents at latitudes from 31 01 South to 77 00 North. Mean melatonin concentration was found to negatively correlate with age, weight, and height. When the sexes were considered separately melatonin only correlated with age for female and with age and weight for males. A weak correlation with latitude, but not longitude, was also found. Received: 26 February 1998 / Accepted: 9 September 1999  相似文献   
    99.
    Illusory contours provide a striking example of the visual system's ability to extract a meaningful representation of the surroundings from fragmented visual stimuli. Psychophysical and neurophysiological data suggest that illusory contours are processed in early visual cortical areas, and neuroimaging studies in humans have shown that Kanizsa-type illusory contours activate early retinotopic visual areas that are also activated by real contours. It is not known whether other types of illusory contours are processed by the same mechanisms, nor is it clear to what extent attentional effects may have influenced these results, as no attempt was made to match the salience of real and illusory stimuli in previous imaging studies. It therefore remains an open question whether there are any brain regions specifically involved in the perception of illusory contours. To address these questions, we have used 15O-butanol positron emission tomography (PET) and a novel kind of illusory contour stimulus that is induced only by aligned line ends. By employing a form discrimination task that was matched for attention and stimulus salience across conditions we were able to directly contrast perception of real and illusory contours. We found that the regions activated by illusory contour perception were the same as those activated by real contours. Only one region, located in the right fusiform gyrus, was significantly more strongly activated by perception of illusory contours than by real contours. In addition, a principal component analysis suggested that illusory contour perception is associated with a change in the correlation between V1 and V2. We conclude that different kinds of illusory contours are processed by the same cortical regions and that these regions overlap extensively with those involved in processing of real contours. At the regional level, perception of illusory contours thus appears to differ from perception of real contours by the degree of involvement of higher visual areas as well as by the nature of interaction between early visual areas.  相似文献   
    100.
    van Assen MA  Vos PG 《Vision research》1999,39(26):3142-4392
    Visual interpolation between dots responsible for rectilinear versus curvilinear contour interpretation was examined with the psychophysical forced directional response (FDR) paradigm. Regular four-dot polygon segments, together with a target dot, were presented to the subjects for 150 ms. Subjects were required to indicate the direction of deviation of the target dot from the midpoint of the intermediate line segment. Crucial variables were the outer angle of the line segments and symmetry axis orientation of the polygon segment. Logistic regression analyses showed that curvilinear interpolation occurred for angles up to 30 degrees, but emerged more pervasively under the vertical symmetry axis orientation for angles up to 60 degrees.  相似文献   
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