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Care-giving and care-seeking behaviours of parents who take their children to an emergency department for non-urgent care.

OBJECTIVE: This study explored the care-giving and care-seeking behaviours of parents who took their children to the emergency department (ED) of a large urban hospital in Western Canada for non-urgent care. METHOD: Data were collected from a convenience sample of 114 parents during a two-week period in January 1992, using a self-administered 53-item questionnaire. The data were analyzed using nonparametric statistics (Chi-square) and thematic content analysis. RESULTS: Eighty-two percent of parents were unsure of or overestimated the seriousness of their child's illness or injury. Prior to attending the ED, 40% of parents administered comfort measures and 45% gave medications. Only 17% of parents used at-home reading materials, while 31% sought lay advice. Fifty-eight percent of parents did not try to contact their family physician or the ED by telephone before coming to the ED. Forty-eight percent of parents who phoned their family physician were unable to obtain advice, and those who did were almost always referred to the ED. Eighty-eight percent of those who phoned the ED were instructed to bring the child to the ED. INTERPRETATION: The results suggest the need for more acceptable, accessible community primary care services.

Adult↗

Sex-related patterns in the profiles of human urinary amino acids.

The urinary amino acid profiles of 79 young women and 72 young men were studied with an automated highpressure amino acid analyzer. A nonparametric statistical analysis was applied for detecting profile differences related to sex and other variables. A strong sex-related pattern was confirmed and its power for sex determination was evaluated. For the women, profile differences related to the use of oral contraceptives were also discovered and evaluated. No correlation with the menstrual cycle was detected.

Adolescent↗

Electromyographic study of the masseter muscle in individuals with Class II malocclusion.

The objective of this work was to study the action of the masseter muscle through electromyography and to analyze the difference of action potential generated by several pre-established jaw movements in individuals with Class II malocclusion. It was studied nine young individuals from both sexes, with ages ranging from 17 to 35, with no history of orthodontic treatment and/or having some kind of alteration in the temporomandibular joint (T.M.J.). In order to collect the electromyographic signs we have used a TECA TE-4 Electromygraph and surface electrodes type Beckman. The data were submitted to nonparametric statistical analysis by Friedman test. The response variables left occlusive contact, free protraction, protraction with occlusive contact, incisor mastication, right molar mastication and forced central occlusion movements showed significant outcomes. Thus we have concluded that as the occlusive balance suffers alterations, the malocclusions become predominant and the masseter muscle undergoes functional and structural modifications.

Action Potentials↗

Influence of choking and arm lock technique in judo on the acoustic reflex threshold (art) in healthy well-trained male and female judoka.

The objective of this controlled parallel group study was to assess the effects of standardized choke holds (test) and arm lock techniques (controls) in on the acoustic hearing threshold. 104 (test group, 32 female subjects and 72 male subjects, mean age = 28.0 years, SD = 7.9 years) and 51 experienced judoka (controls. 21 female subjects, 30 male subjects; mean age = 26.8 years; SD = 13.2 years) participated. Acoustic reflex thresholds (ART [dB]) were measured separately before and after each manoeuvre both for air and bone conduction of the right and left side. The difference Dart of the ART before and after a manoeuvre (Dart = ARTbefore - ARTafter) was calculated. Data were presented descriptively and nonparametric statistics was applied for nonrelated (Kruskal Wallis ANOVA) or related samples (Friedman ANOVA). Wilcoxon tests were used for pre/post comparisons of original ART values. The effect of choking on Dart was significantly different from the effect of the arm lock technique on Dart independent of the experimental condition. A significant influence of applied frequencies on Dart was ascertained if a choking technique was used. For all frequency ranges applied a highly significant improvement of the ART after choking was found. With regard to bone conduction thresholds increased by an average of 6.1 dB and for air conduction the average increase was 4.9 dB. On the contrary, arm locks induced a slight mean deterioration of the ART for bone conduction of 1.8 dB. The ART for bone conduction also showed a trend towards a reduction after arm locks with a mean decrease of about 1.2 dB. In conclusion, standardized choking manoeuvres reduced the ART corresponding to an improved hearing both with regard to air and bone conduction. Such an effect on hearing ability was not found for arm lock techniques.

Adolescent↗

Magnetic source imaging demonstrates altered cortical distribution of function in patients with arteriovenous malformations.

OBJECTIVE: Arteriovenous malformations (AVMs) can be treated successfully, but treatment can pose unacceptable risks if the AVM is located in eloquent cortex. Because AVMs are developmental lesions, the location of primary cortical function may be deranged. We used magnetic source imaging (MSI) to identify the central sulcus and to determine whether primary cortical function was shifted in a set of 30 patients. We correlated these findings with outcome after treatment. METHODS: We retrospectively analyzed the clinical data of 30 patients with AVMs who underwent MSI. Nonparametric statistical comparisons were made to correlate the proximity of AVMs to primary cortex and somatosensory shift to outcome at 12 months. RESULTS: Using MSI, 14 patients (47%) were found to have AVMs involving primary cortex, and 10 patients (33%) were found to have shift in the somatosensory homunculus. Primary cortical involvement was neither required nor sufficient to cause shift (Mann-Whitney U test, z = -0.02, P = 0.31). Patients with AVMs involving primary cortex fared worse after treatment than did patients with AVMs that spared primary cortex (Mann-Whitney U test, z = -2.3, P = 0.02). The presence or absence of shift did not correlate with outcome after treatment (Mann-Whitney U test, z = -0.18, P = 0.48). CONCLUSION: MSI showed that some patients with AVMs have abnormal cortical distribution of function. The involvement of primary cortex correlated with worse outcome after treatment. Our results suggest that preoperative functional imaging may help to better estimate treatment risks and ultimately to guide therapeutic planning.

Adolescent↗

Language abilities of 18-month-old Zulu speakers.

The receptive, expressive and pragmatic language abilities of 18-month-old Zulu speakers were assessed in order to obtain preliminary norms. Twenty-five participants of the Birth to Ten cohort study were investigated using parent reports, mother-child and tester-child interactions. Data was transcribed and analysed using nonparametric statistics. Results demonstrated that receptively subjects understood two-part instructions. Expressively, the mean lexicon was 4.12 words and mean length of utterance 0.65. Pragmatically, subjects were functioning on a nonverbal level and exhibited culture-specific items. The results provided information which could enable speech, language and hearing therapists to engage in primary and secondary prevention. An appropriate test battery for these children is discussed.

Child Language↗

[Various indicators of the hormonal profile in patients with neuroses after psychopharmacotherapy and functional test with sinacten].

Studies of adenohypophyseal hormones, cortisol, T3, T4, thyroxine-binding globulin, testosterone, progesterone and estradiol in 90 neurotic men, treated or not with amitriptyline and benzodiazepines, allowed a conclusion that in the majority of them, endocrine functions were activated. 11 healthy men and 11 male patients underwent the three-day test with sinacten-depot (1 mg intramuscularly). The functional test data were compared over time by the methods of nonparametric statistics. The patients manifested a decrease of reserve potentialities of the pituitary-adrenal system, redistribution of the fractions of thyroid hormones, gonadotropins, the progesterone/estradiol ratio, a rise of prolactin and testosterone secretion. The drugs were found to improve the functioning of the pituitary-adrenal system. However, they did not contribute much to the positive changes in the pituitary-thyroid and other systems.

Adrenal Cortex Hormones↗

Second- and third-trimester serum levels of placental proteins in preeclampsia and small-for-gestational age pregnancies.

BACKGROUND: Poor placentation may perpetuate preeclampsia, but the presence of a major placental pathology has been questioned in cases of preeclampsia where the newborn has an appropriate birthweight for gestational age. On the other hand, poor placentation is also observed in the absence of preeclampsia, in pregnancies with small-for-gestational-age (SGA) fetuses. In late gestation, maternal serum levels of placental protein hormones are changed in both preeclampsia and SGA, but no longitudinal pre-onset studies are available for pregnancy-associated plasma protein A (PAPP-A), pregnancy-specific beta1-glycoprotein (SP1) or human placental lactogen (HPL). METHODS: In a nested case-control study we compared maternal serum levels of PAPP-A, SP1, HPL and placenta growth factor (PLGF) at 17, 25 and 33 weeks in pregnancies developing preeclampsia without fetal growth restriction (n = 28), or characterized by a growth-retarded fetus (n = 25), with gestation-matched controls (n = 65). The proteins were quantified using microplate enzyme immunometric assays and the serum levels at 17, 25 and 33 weeks compared between the three groups by nonparametric statistical tests. RESULTS: In pregnancies with subsequent preeclampsia PAPP-A, SP1, HPL and PLGF were reduced at 17 weeks of gestation whereas at 25 and 33 weeks only PLGF remained below the controls. In growth-restricted pregnancies PAPP-A, SP1 and HPL were reduced at 17 weeks, and only HPL continued to be strongly affected thereafter. CONCLUSION: The reduced serum levels of the placental proteins PAPP-A, SP1 and HPL in the early second trimester (17 weeks) in pregnancies with subsequent preeclampsia or with fetal growth restriction involve an underlying role for the placenta in either pathology independent from the other.

Adult↗

Medical students' opinions on physicians' strike: cross sectional questionnaire study.

AIM: To investigate what Zagreb Medical School students think about general physicians' strike in Croatia, which began in February 2003. METHODS: We surveyed 771 students using a specially designed anonymous self-report questionnaire. In addition to questions on demographic data (student's sex, year of studies, average grade, and whether at least one parent was a physician), the questionnaire contained 19 items divided in three subscales, each assessing different aspects of student opinion on the strike. The first subscale, "Support", assessed students' opinion on situations where strike was an acceptable solution (8 items, alpha=0.82). The second one was "Consequences", assessing students' opinion on possible negative consequences of physician's strike (8 items, alpha=0.77). The third subscale, "Croatia", assessed students' opinions about the social and economic status of physicians in Croatia (3 items, alpha=0.73). Items were graded on a 5-point Likert-type scale. Data were analyzed with nonparametric statistics (Mann-Whitney test, Sperman's r), and the significance level was set at p<0.05. RESULTS: Students scored high on the "Support" subscale (median=34, range=8-40, interquartile range=6;) and were undecided on the "Consequences" subscale (median=23, range=8-40, interquartile range=8), whereas on the "Croatia" subscale, their scores were low, reflecting their poor opinion on the physicians status in Croatia (median=6, range=3-15, interquartile range=4). Students in the clinical years, as well as students whose one or both parents were physicians, scored higher on the "Support" subscale and lower on the "Consequences" and "Croatia" subscales than their colleagues from preclinical years or students whose neither parent was a physician (p<0.001 for all, Mann-Whitney test). No differences were found according to the students' sex, and there was no correlation between average grades and subscale scores. CONCLUSION: Zagreb Medical School students supported the physicians' strike and were undecided on its negative consequences. They thought that physicians' status in Croatia was poor. This trend was more obvious among students in clinical years whose one or both parents were physicians.

Attitude↗

Management of thoracolumbar fractures with accompanying neurological injury.

The optimal surgical approach for spinal canal reconstruction of thoracolumbar fractures is controversial, and the relationship between spinal canal reconstruction and neurological recovery remains unclear. To address these issues, 22 consecutive cases of thoracolumbar fracture with accompanying neurological deficit were reviewed. Neurological status was graded at the time of admission, postoperatively, and at a mean of 15 months postinjury. By using preoperative and postoperative radiographs and computed tomographic scans, the degree of spinal canal compromise was quantified in the sagittal, coronal, and axial planes. All fractures were stabilized by posterior instrumentation and fusion, and in 10 injuries, retropulsed vertebral body fragments were further reduced by posterolateral decompression. Spinal canal dimensions, neurological function, and operative approach were compared by using nonparametric statistical analysis. The greater the initial spinal canal compromise, the more severe the neurological deficit (P = 0.04). With injuries involving L1 and above, this relationship increased (P = 0.003). The extent of spinal canal reconstruction failed to correlate with neurological recovery. Compared with spinal instrumentation alone, transpedicular decompression showed no benefit in terms of postoperative canal dimensions or neurological outcome. On the basis of this experience, transpedicular decompression offers no advantage over spinal instrumentation alone. The relationship between initial spinal canal encroachment and neurological deficit demonstrates that the degrees of bony and neurological injury directly reflect the kinetic energy transferred at the time of impact. The lack of correlation between the extent of spinal canal reconstruction and neurological recovery suggests that ongoing neural compression/distortion contributes little to the overall neurological injury.

Adolescent↗

Theory-based study of the basic values of 565 physical therapists.

BACKGROUND AND PURPOSE: There is a prevailing belief expressed in the physical therapy literature that values influence behavioral choices. There is, however, meager research on physical therapists' values. A values theory was used to study the organization of physical therapists' basic values and to generate hypotheses about age-related value priority differences. SUBJECTS: Participants were volunteers from the Wisconsin Physical Therapy Association (N=565). METHODS: Values importance ratings were gathered using a modified Schwartz Values Survey. Demographic data were obtained with an investigator-developed questionnaire. Analyses included descriptive and nonparametric statistics and nonmetric multidimensional scaling. RESULTS: The organizational structure of therapists' values was similar to the theoretical model. Physical therapists rated values associated with benevolence as most important and values associated with power as least important. Three of 7 age-related hypotheses were supported. DISCUSSION AND CONCLUSION: The theory adequately explained the organization of physical therapists' values and provided rational explanations for age-based value priority differences. Compared with occupationally heterogeneous samples, the results suggest that physical therapists highly prize values that benefit others and give remarkably little importance to values associated with power.

Adult↗

Nicotine induced proliferation and cytokine release in osteoblastic cells.

Smoking has deleterious effects on osteoporosis and periodontitis both characterized by bone loss. Smoking also interferes with the protective effect that hormone replacement therapy (HRT) has on bone loss. Our study investigated two mechanisms by which smoking may affect bone metabolism: nicotine-induced proliferation and nicotine-induced cytokine secretion in osteoblasts. Two osteoblastic cell models were used: mouse osteoblasts derived from mouse calvaria and human osteoblasts. Thymidine incorporation and immunoassays were used to evaluate proliferation, interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) secretion. Parametric and nonparametric statistical analyses were used for comparisons. The results showed that nicotine induced stimulation and inhibition of proliferation in both osteoblastic cell models. In human osteoblasts, the proliferative and inhibitory effects were also donor dependent. Il-6 secretion showed different patterns in mouse and human osteoblasts. In mouse osteoblasts, nicotine significantly increased IL-6 secretion and estradiol significantly inhibited the nicotine-induced IL-6 release. In human osteoblasts, cells derived from one subject did not respond to nicotine. However, in the second sample, nicotine increased secretion of Il-6 but estradiol did not oppose this effect. In human osteoblasts, nicotine also induced an increase in the TNF-alpha secretion and estradiol opposed this increase. These results suggest that nicotine affects bone metabolism by modulating proliferation, and Il-6 and TNF-alpha secretion. These studies provide a possible explanation for differences in bone loss among subjects who smoke and offer a possible mechanism for the oppositional effect of smoking on HRT in subjects with bone loss.

Animals↗

Functional electrical stimulation changes dynamic resources in children with spastic cerebral palsy.

BACKGROUND AND PURPOSE: Children with cerebral palsy (CP) often are faced with difficulty in walking. The purpose of this experiment was to determine the effects of functional electrical stimulation (FES) applied to the gastrocnemius-soleus muscle complex on the ability to produce appropriately timed force and reduce stiffness (elastic property of the body) and on stride length and stride frequency during walking. SUBJECTS AND METHODS: Thirteen children with spastic CP (including 4 children who were dropped from the study due to their inability to cooperate) and 6 children who were developing typically participated in the study. A crossover study design was implemented. The children with spastic CP were randomly assigned to either a group that received FES for 15 trials followed by no FES for 15 trials or a group that received no FES for 15 trials followed by FES for 15 trials. The children who were having typical development walked without FES. Kinematic data were collected for the children with CP in each walking condition and for the children who were developing typically. Impulse (force-producing ability) and stiffness were estimated from an escapement-driven pendulum and spring system model of human walking. Stride length and stride frequency also were measured. To compare between walking conditions and between the children with CP and the children who were developing typically, dimensional analysis and speed normalization procedures were used. RESULTS: Nonparametric statistics showed that there was no significant difference between the children with CP in the no-FES condition and the children who were developing typically on speed-normalized dimensionless impulse. In contrast, the children with CP in the FES condition had a significantly higher median value than the children who were developing typically. The FES significantly increased speed-normalized dimensionless impulse from 10.02 to 16.32 when comparing walking conditions for the children with CP. No significant differences were found between walking conditions for stiffness, stride length, and stride frequency. DISCUSSION AND CONCLUSION: The results suggest that FES is effective in increasing impulse during walking but not in decreasing stiffness. The effect on increasing impulse does not result in more typical spatiotemporal gait parameters.

Cerebral Palsy↗

[Determination of the quantitative composition of fecal microflora].

Shifts in the quantitative composition of fecal microflora may be assessed by estimating the summary share (in per cent) of the bacterial groups associated with fecal microbiocenosis, this share being estimated by the nonparametric statistics methods. The ratio between potentially dominating and concomitant groups of microorganisms in fecal microbiocenosis helps estimate the severity of disorders in the quantitative composition of fecal microflora.

Diarrhea↗

Considerations in design and use of scales in rehabilitative audiology.

Self-assessment questionnaires in rehabilitative audiology typically possess the measurement characteristics of scales based on forced-choice and rank-order. Data from these ordinal scales neither support arithmetic analysis nor arithmetic interpretation. However, powerful nonparametric statistics are available for application to data from ordinal level questionnaires. Thus, methodologic principles influence the way self-assessment scales are designed, constructed, and analyzed. They also influence the way clinicians interpret responses from individual patients. Within these constraints, well constructed questionnaires can provide information on a wide range of topics in rehabilitative audiology. Suggestions are given for generating interval level questionnaires that are more precise than existing, ordinal level scales.

Audiology↗

Sex-related differences in the nuclear population of postpubertal rat pineal gland. A quantitative study.

Male and female parenchymal pineal cell types have been studied throughout postpubertal development to determine the existence of sex-related differences on a time basis. Six age groups (2, 3, 4, 8, 15 and 24 months) of eight rats (4 males and 4 females) were used in this study. Nuclei of both parenchymal pineal cell types were counted in 5 areas of 26.377 microns 2 per pineal gland on semithin sections. Nonparametric statistics of our results (Mann-Whitney U-test and Kruskal-Wallis H-test) demonstrated significant differences between male and female pinealocytes through the stages studied. In all age groups, the number of nuclei per unit area was larger in female rats. Pineoglial cells did not show significant sex-related differences.

Animals↗

Quantitative electroencephalography in dogs anesthetized with 2.0% end-tidal concentration of isoflurane anesthesia.

Quantitative electroencephalography was assessed in dogs under controlled, 2% end-tidal isoflurane anesthetic conditions, and each variable at each electrode site was tested for normal distribution. With the quantitative electroencephalographic system used, 16 values for each of 21 electrode sites were evaluated. Absolute power ratios also were evaluated. The methods for quantitative electroencephalographic recording and analysis appear to be readily adaptable to the dog. Most of the data do not conform to a normal distribution. Therefore, distribution-free nonparametric statistics should be used when looking for differences under experimental or clinical conditions. Quantitative electroencephalography appears to be a sensitive noninvasive method that could be used to evaluate brain function under anesthetic, clinical, and experimental settings.

Acid-Base Equilibrium↗

Electromyography interference pattern decomposition.

Decomposition of an interference pattern enables examination of individual electromyography (EMG) motor units and their firing rates at more than minimal contraction forces. In this decomposition method, significant events with a constant occurrence (near motor unit action potentials) can be enhanced, and unwanted events (distant motor unit action potentials, artifacts) eliminated, by calculating the average accumulated change while sliding a fixed-width window along the digitized EMG interference pattern. Nonparametric statistical methods are then applied to these data to determine which information is significant at the .05 level. The exact duration of significant information is identified without the need for arbitrary thresholds and filters to eliminate unwanted information. Events are then classified into groups of similar events by comparing: (1) correlation coefficients, (2) point-to-point differences, (3) amplitudes, and (4) areas. The classification is further refined by the use of firing-rate information.

Action Potentials↗