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1.
OBJECTIVE: Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In recent years, various studies have been published stating that children with nocturnal enuresis exhibit growth and skeletal maturation retardation. METHODS: In this cross-sectional study, we included 27 patients (16 boys, 11 girls) between the ages of 6 and 14 years who had presented with primary nocturnal enuresis (PNE) complaints. We included in the evaluation 19 healthy subjects (12 boys, 7 girls), who were the siblings of the children with PNE, as the control group. RESULTS: The patients in both groups were similar in chronological age, bone age, height and weight, with no significant difference between groups (P>0.05). CONCLUSION: The two groups in our study consisted of the same genetic background. Thus, our results were found to be different from the previous studies. We have concluded that there is no direct relationship between enuresis nocturnal and skeletal maturation.  相似文献   
2.
Thirteen children with acute lymphoblastic leukemia (ALL) were investigated before and during cytotoxic therapy. EEG findings were correlated with the clinical course and the therapy protocol and compared with normal data obtained from 295 healthy children. Frequency analysis of the background activity of the EEG revealed an initial slowing of the background activity prior to therapy and further slowing each time a combination of vincristine (VCR), daunorubicine (DAU) or adriblastine (ADR), prednisone (FRED), and L-asparaginase (L-ASP) was administered. The slowing of the background activity correlated only with the administration of these drugs. DAU, ADR, and FRED are not known to influence the EEG; therefore, VCR and L-ASP remain the primary candidates responsible for the central nervous system alteration.  相似文献   
3.
The smooth pursuit system moves the eyes in space accurately while compensating for visual inputs from the moving background and/or vestibular inputs during head movements. To understand the mechanisms underlying such interactions, we examined the influence of a stationary textured visual background on smooth pursuit tracking and compared the results in young and adult humans and monkeys. Six humans (three children, three adults) and six macaque monkeys (five young, one adult) were used. Human eye movements were recorded using infrared oculography and evoked by a sinusoidally moving target presented on a computer monitor. Scleral search coils were used for monkeys while they tracked a target presented on a tangent screen. The target moved in a sinusoidal or trapezoidal fashion with or without whole body rotation in the same plane. Two kinds of backgrounds, homogeneous and stationary textured, were used. Eye velocity gains (eye velocity/target velocity) were calculated in each condition to compare the influence of the textured background. Children showed asymmetric eye movements during vertical pursuit across the textured (but not the homogeneous) background; upward pursuit was severely impaired, and consisted mostly of catch-up saccades. In contrast, adults showed no asymmetry during pursuit across the different backgrounds. Monkeys behaved similarly; only slight effects were observed with the textured background in a mature monkey, whereas upward pursuit was severely impaired in young monkeys. In addition, VOR cancellation was severely impaired during upward eye and head movements, resulting in residual downward VOR in young monkeys. From these results, we conclude that the directional asymmetry observed in young primates may reflect a different neural organization of the vertical, particularly upward, pursuit system in the face of conflicting visual and vestibular inputs that can be associated with pursuit eye movements. Apparently, proper compensation matures later. Electronic Publication  相似文献   
4.
AIM: Digital imaging is useful in conventional photography because it immediately provides images, and the image quality can be improved afterwards by the use of computer programs. The major disadvantages of consumer-type digital cameras mounted on microscopes are (i) unequal illumination through the image, and (ii) a coloured background. A computer program was specifically adapted and refined to improve images obtained with consumer-type digital cameras mounted on microscopes. METHODS AND RESULTS: An approach using a division operation between the specimen image and a background image leads to homogeneous illumination throughout the image, with automatically corrected brightness and white background. The correct colour spectrum is preserved by correction of the histogram. This approach was obtained from the freeware computer program 'Image Arithmetic'. In a test, three different consumer-type digital cameras (Sony, Nikon, Olympus) on different microscopes were used to obtain images of different types of histological specimens (cervical smear, bone marrow biopsy, and colonic biopsy). The computer program dramatically improved the quality of images obtained with all tested cameras. CONCLUSION: Using this approach, even low-cost digital cameras mounted on microscopes produce brilliant images with homogeneous illumination and a white background, the image quality being comparable with expensive cameras especially designed for microscopes.  相似文献   
5.
Guy's, King's, and St. Thomas's School of Medicine encourages students to learn anatomy from human dissection. Today, there is a worldwide move of anatomy-based teaching away from dissection to prosection. This study investigates how attitudes toward dissection vary with gender and ethnicity. We assessed students' reactions and concerns regarding the dissecting room, any coping strategies they use to combat them, and analyzed effective methods of teaching anatomy to medical and dental students. Three questionnaires were distributed amongst 474 first-year medical and dental students before dissection and 1 week and 12 weeks after exposure to the dissecting room. Over the 3 months we found significant changes in the concerns of students about dissection. There were also significant differences (P < 0.05) between medical and dental students, males and females, and students of differing ethnic backgrounds, which persisted over 12 weeks. Both medical and dental students found tutorials and textbooks of most value in learning anatomy. Dental students found prosection more useful than medical students (P < 0.001) though neither group demonstrated a significant preference for prosection over dissection. Of concern, 7% reported recurring images of cadavers and 2% insomnia after commencing dissection. Interest in the subject matter and discussion were the commonest methods used to combat stress. This study contributes to the ongoing debate about the value of the dissecting room in the medical school curriculum.  相似文献   
6.
In an attempt to identify prognostic factors, non-drug users and abusers in the Gothenburg year cohort of 1953 were compared with reference to background data. Individuals with chronic abuse differed most from the "normal" group. Prognostic factors for drug abuse were: member of a multiproblem family, child psychiatric care, contact with the Social Welfare Administration at an early age, truancy, placement in special class, premature drop-out from school, admitted high-frequency drug use in a school questionnaire, for boys early registration for crimes and for girls nervous complaints. The results indicate the necessity of earlier and more effective prevention.  相似文献   
7.
〔目的〕掌握肖厝口岸鼠形动物所携带的恙螨的种类、分布和季节消长的本底情况。〔方法〕从2004年8月 ̄2005年7月分别采用捕鼠夹和捕鼠笼对肖厝口岸的鼠形动物所携带的恙螨的种群构成、季节消长进行了调查。〔结果〕本次调查共捕获鼠形动物60只,其中22只携带恙螨,共检集恙螨2938只,经鉴定隶属2科2属4种,其中地理纤恙螨为优势种,占总恙螨数的74.13%。恙螨全年平均密度(恙螨指数)为48.97,鼠体染恙螨率为36.67%。优势鼠种黄胸鼠的恙螨密度最高,为102.48,鼠体染恙螨率为59.26%。全年的季节消长有3个高峰期,最高峰月份为5月。〔结论〕肖厝口岸优势鼠种携带的恙螨率较高,存在着恙虫病发生的可能性。改善港区办公大楼及食堂室内外和与港区连接部的海龙餐馆室内外的环境卫生,消灭恙螨孽生地,加强防治知识的宣传以及开展群众性灭鼠是我们今后工作的重点。每年的5月和12月是开展灭鼠、灭螨的最好时机。  相似文献   
8.
Of the Dutch school population 0.1% suffer from a hearing loss which makes it necessary for them to attend a special school. This permanent, binaural hearing impairment is of a moderate to severe degree (degrees II and III) and adversely affects the child's linguistic skills and school performance. Of the pupils attending ordinary schools 4–5% suffer from a hearing loss which, according to the Dutch audiologist Huizing, lies on the borderline of a slight to moderate hearing impairment (degrees I and II). This loss is characterised by its temporary nature, the fact that it is monaural in 71% of the cases and that there is no evidence for its clearly affecting the learning process. The risk of hearing impairment is predominantly determined by the child's family background.  相似文献   
9.
Abstract

Objective: Word recognition is a basic component in a comprehensive hearing evaluation, but data are lacking for listeners speaking two languages. This study obtained such data for Russian natives in the US and analysed the data using the perceptual assimilation model (PAM) and speech learning model (SLM). Design: Listeners were randomly presented 200 NU-6 words in quiet. Listeners responded verbally and in writing. Performance was scored on words and phonemes (word-initial consonants, vowels, and word-final consonants). Study sample: Seven normal-hearing, adult monolingual English natives (NM), 16 English-dominant (ED), and 15 Russian-dominant (RD) Russian natives participated. ED and RD listeners differed significantly in their language background. Results: Consistent with the SLM, NM outperformed ED listeners and ED outperformed RD listeners, whether responses were scored on words or phonemes. NM and ED listeners shared similar phoneme error patterns, whereas RD listeners’ errors had unique patterns that could be largely understood via the PAM. RD listeners had particular difficulty differentiating vowel contrasts /i-I/, /æ-ε/, and /ɑ-Λ/, word-initial consonant contrasts /p-h/ and /b-f/, and word-final contrasts /f-v/. Conclusions: Both first-language phonology and second-language learning history affect word and phoneme recognition. Current findings may help clinicians differentiate word recognition errors due to language background from hearing pathologies.  相似文献   
10.
Nosocomial infections pose a significant and escalating threat to both patients and healthcare workers (HCWs). By their nature, hospitals induce antibiotic resistance in virulent and commensal strains, leading to increasingly severe hospital-acquired infections. This study measured environmental exposure experienced by domestic staff cleaning vacated patient rooms of a community hospital to bacteria in ambient bioaerosols. While they cleaned the room, participants wore an N95 filtering facepiece respirator (FFR), from which coupons were cut and bacteria were extracted, cultured and enumerated. Extrapolation to the full area of the respirator yielded measured exposures of 0.2–1.4 × 104 colony-forming units/hour, of which ~97% collected on the front layer of the N95, suggesting a possible role for minimal respiratory protection in nonpatient environments. Random resistance testing of 1.6% of the isolates showed that ~70% of both Gram-positive and Gram-negative organisms exhibited resistance to oxacillin and ~9% of the Gram-positives displayed resistance to vancomycin. These data provide an estimate for mask bioaerosol loading that can be used in risk modeling and to refine strategies for reuse of FFRs during critical shortages.  相似文献   
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