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991.
Results of an hierarchical factor analysis with university students (N = 101) do not support the construct validity of the Multidimensional Aptitude Battery (MAB). Although the MAB Full Scale IQ seems to be a valid measure of general mental ability, the construct validity of the Verbal and Performance scale IQs is not supported. Therefore, the Verbal and Performance IQs should be interpreted with caution, if at all. In addition, re-analysis of previous investigations of the MAB underscores the importance of ascertaining the reading level of subjects prior to the administration of the MAB. Marginal reading proficiency, especially on a timed paper-and-pencil test such as the MAB, will confound results.  相似文献   
992.
Variations of the medial and inferior choanal limits may facilitate snoring. These are: 1) short vomer without crista choanalis vomeris and adaptational formations, 2) extremely concave posterior margin of the hard palate leading to disproportion between the muscular and aponeurotic part of m. tensor veli palatini and hence to a flabby soft palate especially during sleep, and 3) neonatal relation of the height and width of the choane resulting in a very large choanal region instead of relative reduction of choanal width compared to its increasing height. All these variations result in a flabby soft palate especially during sleep and may lead to formation of whirles of inspired air and snoring.  相似文献   
993.
Various forms of signal processing are used in modern ASP hearing aids. The present study investigated the relationship between sentence recognition ability and two types of signal processing used in commercially available hearing aids. Results indicated a significant improvement in sentence recognition ability employing an instrument with adaptive compression (variable release time) versus an instrument with an adaptive high-pass filter with short attack and release times. Data were obtained for a single-talker competing message at several message-to-competition ratios. The adaptive compression system may prove to be beneficial to hearing-impaired listeners in certain background noise environments.  相似文献   
994.
Fronto-ethmoidal mucocoeles: a histopathological analysis.   总被引:1,自引:0,他引:1  
From a series of 118 fronto-ethmoidal mucocoeles, 40 specimens have been submitted to detailed histological analysis. The frequency of each epithelial and sub-epithelial component is considered and reveals features which support a dynamic theory of bone resorption and formation rather than that of pressure erosion in the pathogenesis of mucocoeles.  相似文献   
995.
Facial reanimation after acoustic neuroma excision is currently accomplished using a variety of surgical techniques. A multi-institutional survey of patient perceptions of facial reanimation success was accomplished by mailing a questionnaire to 809 randomly selected members of the Acoustic Neuroma Association. Four hundred sixty patients who underwent 296 reanimation procedures responded. Facial to hypoglossal nerve anastomosis, tarsorrhaphy, and upper eyelid implants were most frequently performed. The patient's estimations of initial deficit, spontaneous recovery, and overall satisfaction with the reanimation procedures are discussed.  相似文献   
996.
The degree of metabolic acidosis at birth has been calculated in cord artery and vein samples from 21 term fetuses with cord artery pH less than 7.20. The aim of the study was to compare base deficit values calculated from either Siggaard-Andersen alignment nomogram (BD blood) or the Acid-Base chart (BD extra cellular fluid, BDecf). BDblood was found to be consistently higher in the cord artery as compared with BDecf, 13.2 +/- 3.5 and 9.9 +/- 2.9 mmol/l (Mean +/- SD), respectively. A significant correlation was found between cord artery PCO2 and BDblood whereas BDecf appeared unaffected by PCO2. In cases with cord entanglement BDecf a-v differences were increased to 3.4 +/- 2.3 mmol/l as compared with the small a-v difference noted in acidotic cases without cord entanglement, 1.1 +/- 1.25 mmol/l. It is speculated that with acutely emerging, intermittent asphyxia due to cord compression, a cord artery and vein difference in metabolic acidosis may exist and where the vein captures the basal level and the artery the acute changes. It is concluded that BDecf in both cord artery and vein add valuable information on the mechanisms behind metabolic acidosis.  相似文献   
997.
We tested the urine of 30 infants 6 weeks to 7 months of age after they received standard 10-micrograms (0.5-ml) doses of HbOC (HibTITER) Haemophilus influenzae b (Hib) conjugate vaccine for the presence of Hib antigenuria using a commercially available latex particle agglutination assay (Directigen). Urines were collected within 1 hour, from 1 to 3 hours, at 24 hours and at 3, 6 and 9 days after vaccine administration and reactions were quantitated from 0 to 3+. In contrast to previous studies in older children which showed little or no antigenuria following HbOC vaccination, our study shows that in infants intense Hib antigenuria is evident within 2 to 3 hours and persists 3 days after vaccine administration and that less intense antigenuria may be detected in some infants for several days. With efficacious vaccines now being used in 2- to 6-month-old infants, invasive Hib disease may soon be limited to infants of this age just before their seroconversion. It should be recognized that antigenuria occurs for several days after vaccination with Hib conjugate vaccines and that it could be erroneously interpreted as evidence of invasive Hib infection.  相似文献   
998.
Bone mineral density of the lumbar spine in women with endometriosis   总被引:2,自引:1,他引:1  
Young women with endometriosis have reduced cortical and trabecular bone mineral density of the wrist compared with age-matched controls. This conclusion was based on 41 subjects from one geographical location. The purpose of this study was to test this finding in a larger, more geographically diverse population. One hundred women with laparoscopically proven endometriosis were enrolled in this study for the evaluation of the efficacy of nafarelin, a gonadotropin-releasing hormone agonist. Patients were recruited from nine investigators across the United States and Canada, and bone mineral density of the lumbar spine was obtained at baseline, with 6 Hologic QDR (Hologic Inc., Waltham, MA) and a Lunar DPX (Lunar Radiation Corp., Madison, WI) instrument. The age of the women was 30.3 +/- 5.8 years (mean +/- SD); 91% were white. Bone mineral density of the lumbar spine was 1.1 +/- 0.11 g/cm2 (n = 85 Hologic QDR) and 1.2 +/- 0.93 g/cm2 (n = 15 Lunar DPX). Hologic bone mineral density was 104.8 +/- 11.0 and Lunar bone mineral density was 103.4% +/- 7.8% of normal values for age. To conclude, in a population based cross-sectional study of patients with endometriosis, we do not observe low bone mineral density of the lumbar spine by techniques that measure a combination of cortical and trabecular bone.  相似文献   
999.
A prospective study of 17 cases of microsurgical reversal of tubal sterilization by a combined approach of laparoscopy and minilaparotomy was performed. Inclusion criteria included age less than 43; weight less than ideal body weight plus 20%; documentation of ovulation; 2 cm of proximal oviduct on hysterosalpingography; and a normal semen analysis or postcoital test. A comparison group of the 5 cases of sterilization reversal performed by a standard inpatient technique during the same period was analyzed. The study technique was performed on an outpatient basis in 15 of the 17 cases, 12 patients (71%) conceived 13 intrauterine pregnancies, one ectopic pregnancy occurred, and total patient costs and time until return to work were significantly less with the study versus standard technique.  相似文献   
1000.
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