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51.
Measures to prevent cricket injuries: an overview 总被引:6,自引:0,他引:6
Cricket is a major international sport, generally played in British Common-wealth nations. Although strictly a non-contact sport, injuries in cricket can result in a number of ways. In high level cricket, overuse injuries are common and related to the physical demands of the sport, particularly in the delivery of the ball. The bowling action involves repetitive twisting, extension and rotation of the trunk at the same time as absorption of large ground reaction forces over a short period of time. These movements, if performed incorrectly or too frequently, can lead to overuse injuries of the back, particularly in elite and high level cricketers. Cross-sectional studies have demonstrated that spinal overuse injuries occur more frequently to cricketers adopting a mixed bowling action than to those who favour a front- or side-on bowling technique. Strategies to ensure that cricketers do not adopt the mixed action or bowl too fast for extended periods can prevent these back injuries. Injuries resulting from impacts, generally from the cricket ball, can also occur and are more common during low level competition or informal participation. Because of the potential severity of these impacts, a range of protective equipment ranging from body padding to gloves and face protectors are now common features of standard cricket equipment. Although a number of measures to prevent cricket injuries have been widely suggested in the literature, there have been very few studies that have formally assessed their effectiveness in preventing injury. Further research is needed to gain a greater understanding of the biomechanics of cricket actions, the mechanisms of resultant injuries and the role of various risk factors in injury causation. 相似文献
52.
Waller SA Armstrong KJ McGrath AM Sullivan CL 《Journal of autism and developmental disorders》1999,29(6):485-490
This review summarizes subject selection and diagnostic procedures documented in the Journal of Autism and Developmental Disorders. One hundred forty-two empirical articles published between February 1993 and April 1997 were examined. Reviewers independently evaluated articles using a coding instrument developed by the authors. Results indicated that a majority of researchers reported the use of one or more standard diagnostic criteria in classifying their subjects. However, numerous studies did not report the methods by which the diagnostic criteria were quantified or applied. Additionally, there was a lack of clear specification of inclusion and exclusion criteria for comorbid disorders. Improving the documentation of diagnostic practices in research on autism will benefit researchers and practitioners. 相似文献
53.
McGrath J 《Schizophrenia Research》1999,40(3):113-177
The central nervous system is increasingly being recognised as a target organ for vitamin D via its wide-ranging steroid hormonal effects and via the induction of various proteins such as nerve growth factor. This paper proposes that low maternal vitamin D may impact adversely on the developing foetal brain, leaving the affected offspring at increased risk of adult-onset schizophrenia. The hypothesis can parsimoniously explain diverse epidemiological features of schizophrenia, such as the excess of winter births, increased rates of schizophrenia in dark-skinned migrants to cold climates, the increased rate of schizophrenia births in urban versus rural setting, and the association between prenatal famine and schizophrenia. Studies that will allow rejection of the hypothesis are proposed. 相似文献
54.
OBJECTIVE: The current study tested whether adolescent children of alcoholics (COAs) showed poorer academic performance than did demographically matched controls, and whether such parent alcoholism effects varied as a function of heterogeneity within the COA sample. In addition, controlling for parent educational attainment, we examined whether relations between parental alcohol dependence and academic performance could be accounted for by COAs' lower levels of task orientation, heightened levels of environmental stress, lowered levels of family organization and less parental involvement in their school activities. METHOD: A sample of 221 adolescent COAs and 196 demographically matched controls (53% boys, mean [+/-SD] age = 12.7+/-1.46 years), and their parents, were included in the current study. Adolescents were selected from a larger 3-year longitudinal study in which participants were interviewed three times at annual intervals. Those who were interviewed at Time 3 and who had academic achievement data were included in the current analyses. Demographic information and diagnoses of parental alcoholism were collected at Time 1, and data on potential mediators were collected at Time 3. Academic achievement data were collected at Time 3 from school records. RESULTS: Multiple regression analyses indicated that COAs received lower school grades than did their non-COA peers (mean = 2.19+/-1.08 vs 2.54+/-1.01, respectively). COAs with two alcoholic parents (mean = 1.80+/-1.17) and COAs with at least one parent diagnosed alcohol dependent (mean = 2.01+/-1.01) showed particularly low grades. Parental alcohol dependence was also associated with lower math achievement scores (mean = 48.52+/-24.68 vs 62.47+/-26.71). Evidence indicated that adolescents' task orientation mediated the relation between parental alcohol dependence and adolescent grades (indirect effect, t = -2.93, 289 df, p < .01), and between parental alcohol dependence and adolescent math achievement (indirect effect, t = -1.99, 194 df, p < .01). Adolescents' life stress did not mediate the relations of interest after controlling for task orientation. CONCLUSIONS: The current study confirmed that COAs, particularly those whose parents are alcohol dependent as opposed to having a diagnosis of alcohol abuse, achieve relatively lower academic outcomes in comparison to non-COA peers. Adolescent task orientation partially mediated the relations between parent alcohol dependence and academic achievement, indicating that academic difficulties in COAs may be partly due to impaired motivation and organization. 相似文献
55.
Summary Adrenergic mechanisms were analysed in the pithed rat to determine to what extent the actions of drugs observed in vitro are relevant in situ.The drugs examined were those which are known to block the neuronal or extraneuronal uptake of noradrenaline (cocaine, desipramine and corticosterone) or to be antagonists at post and/or pre-junctional -adrenoceptors (prazosin and yohimbine) together with the antidepressant, mianserin, which has been implicated in several of these actions. These drugs were tested against the arterial diastolic pressor, cardiac chronotropic and vas deferens responses to sympathetic nerve stimulation, to indirect sympathomimetics or to direct sympathomimetics, which were chosen according to whether they were substrates for noradrenaline uptake processes or selective between adrenoceptors.Pressor and cardiac responses to sympathetic nerve stimulation or to intravenous noradrenaline were potentiated by blockade of neuronal uptake but only the pressor effect of noradrenaline was potentiated by blockade of extraneuronal uptake. The effects of the antagonists suggested that the pressor effects of noradrenaline and of sympathetic nerve stimulation result from a combination of activation of 1- and 2-adrenoceptors, but that the effect of noradrenaline had a relatively greater contribution from the 2-adrenoceptors. Mianserin was found to potentiate adrenergic responses at low doses, to produce limited antagonism at post-junctional 1-adrenoceptors in high doses but to have no detectable effect at postjunctional 2-adrenoceptors. 相似文献
56.
B P McGrath D J Tiller A Bune J P Chalmers P I Korner J B Uther 《Kidney international》1977,12(4):294-302
Hemodynamic studies were performed at two levels of dietary sodium intake (10 mmoles/day and 100 mmoles/day for 14 days) in a group of patients (with retained kidneys) on chronic hemodialysis. Plasma renin activity and aldosterone, plasma, and extracellular fluid (ECF) volumes were measured while the patient were at rest. Cardiac output, mean intraarterial pressure, and the calculated total peripheral resistance index were recorded while the patients were at rest and during acute "total" autonomic blockade. On the sodium diet of 10 mmoles/day, normotensive and hypertensive patients had similarly low total blood volumes, low-normal ECF volumes, and similar levels of plasma renin and aldosterone. The resting cardiac output was increased in both groups, but the total peripheral resistance was increased only in the patients with hypertension, in whom peripheral resistance was inappropriately high for the degree of anemia. Six hypertensive patients were studied on both diets. The resting mean arterial pressure was greater on the sodium diet of 100 mmoles/day than on the 10 mmoles/day diet, accompanied by increased in plasma volume, extracellular fluid volume, and cardiac output, but no change in peripheral resistance. During autonomic blockade on either diet, there was a marked fall in blood pressure in the patients with hypertension. This was mainly due to a fall in peripheral resistance which reached levels similar to those seen in the normotensive patients whose resistance was unaltered by blockade. Autonomic factors appear to contribute to the elevated peripheral resistance of hypertensive dialysis patients. In these patients, the effect of a high sodium diet, at least over the time-scale studied here, is to increase blood pressure and cardiac output, without the change in peripheral resistance expected from autoregulation. 相似文献
57.
58.
Frequency of the ATM IVS10-6T→G variant in Australian multiple-case breast cancer families
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59.
Neeraj Kaushik MD Debra Brody Neil Christie Kevin McGrath 《Journal of gastrointestinal cancer》2003,34(2-3):95-99
Basaloid squamous cell carcinoma (BSCC) is a rare form of cancer that arises primarily in the upper aerodigestive tract. Esophageal BSCC is extremely rare, accounting for less than 2% of primary esophageal malignancies. It is histopathologically distinct from squamous cell carcinoma and has an aggressive biological behavior with poor survival outcomes. There is no known association of Barrett’s esophagus with esophageal BSCC. Here, we report what we believe is the first such case of esophageal BSCC occurring in the setting of Barrett’s esophagus. 相似文献
60.
Hypospadias trends in two US surveillance systems 总被引:6,自引:0,他引:6
OBJECTIVE: Hypospadias is a common congenital anomaly, the cause of which is unknown. Unexplained increases in the rates of hypospadias occurred in five European countries in the 1970s and 1980s. We examined data from two birth defects surveillance systems in the United States for evidence of similar trends. METHODOLOGY: The Metropolitan Atlanta Congenital Defects Program (MACDP) provided birth prevalence rates from 1968 to 1993. The nationwide Birth Defects Monitoring Program (BDMP) provided rates from 1970 to 1993. MACDP data are population-based and could be categorized by the severity of the hypospadias. BDMP data allowed analysis of rate trends for the four census regions of the United States. RESULTS: Data from both surveillance systems showed an approximate doubling of hypospadias rates in the 1970s and 1980s. MACDP data showed that the rate of severe cases increased while the ratio of mild to severe cases decreased. BDMP data showed that hypospadias rates increased markedly in all four regions of the United States. CONCLUSIONS: The observed increases are unlikely to be attributable to increased sensitivity of the surveillance systems or the identification of more mild cases by physicians over time, because either trend would have increased rather than decreased the ratio of mild to severe cases. If real, these trends represent the largest number of cases and the first report of an increase in hypospadias rates outside of Europe. Additional investigation of a possible increase in hypospadias rates is warranted. 相似文献