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OBJECTIVE: Female athletes who are at increased risk for anterior cruciate ligament (ACL) injury demonstrate biomechanical differences between limbs during athletic tasks that may persist following anterior cruciate ligament reconstruction (ACLR). This may limit an athlete's potential for safe return to sports competition. The purpose of this study was to determine if female athletes demonstrate lower limb asymmetries in landing and takeoff force following ACLR and clearance for return to competitive sports participation. We hypothesized that females following ACLR would demonstrate side-to-side differences in landing and jumping kinetics after their return to sport (2+ years) that would not be observed in a group of healthy female controls. DESIGN: Case control study. SETTING: The Sports Medicine Biodynamics Center at Cincinnati Children's Hospital Medical Center. PATIENTS: Fourteen female athletes at a mean of 27 months following ACLR and 18 healthy female athletes participated in the study. ASSESSMENT: All subjects executed a drop vertical jump (DVJ) task onto 2 force plates. Vertical ground reaction force (VGRF) was measured during landing and takeoff and was used to calculate landing phase loading rates. A 2-way analysis of variance was used to determine differences between the involved, uninvolved, and control limbs. RESULTS: Females who had undergone ACLR demonstrated increased VGRF (P = 0.001) and loading rate (P < 0.001) on the uninvolved limb during landing when compared with the involved limb and the control group. During takeoff, the involved limb showed significantly less ability to generate force (P = 0.03) than the uninvolved limb and the control limbs. CONCLUSIONS: Female athletes who have undergone ACLR and returned to sport may continue to demonstrate biomechanical limb asymmetries 2 years or more after reconstruction that can be identified during landing.  相似文献   
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Abstract: Increasing awareness of health effects of solar ultraviolet radiation has focused attention on protection measures, including sunglasses. Sunglasses, or fashion glasses with tinted lenses, may be associated with some risks, and quality is not evident from casual inspection. This study investigates one possible ‘hazard’ of sunglasses—that they may induce behavioural changes which reduce the wearer's tendency to use adequate sun protection for the rest of the body. Findings consistent with such a proposition were shown in a photographic survey of 373 people in the summer of 1991 in Perth, Western Australia. This revealed maladaptive associations between the wearing of sunglasses and a high degree of leg or arm exposure as recorded by length of sleeves or trouser legs. This was significant for the arms and the legs in males (P < 0.05), but approached significance only for the arms in females (P < 0.10). There was no significant association between degrees of arm and leg exposure in either sex. The health implications of these maladaptive behaviours, and some advantages and disadvantages of the survey technique, are discussed. The results suggest that promotion of sun-protective behaviour should encourage the use of both sunglasses and protective clothing, as subjects' behaviours with respect to these do not appear to be correlated in a rational manner. If public awareness of links between skin cancer and eye disease could be increased, promotion of sunglasses might lead to a reduction in the incidence of skin cancers in general, not just those in the periorbital area.  相似文献   
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Abstract: We aimed to determine the alcohol consumption, blood alcohol levels (BALs) and subsequent driving of patrons leaving 15 hotels and taverns in Perth, Western Australia. Of the 414 patrons approached by interviewers on Friday and Saturday evenings, 307 (74 per cent) consented to take part. Self-reported alcohol consumption, driving intentions, perceived levels of fitness to drive and demographic information were collected using an interviewer-administered questionnaire. Observations of subsequent driving were recorded and BALs were measured by breath-alcohol meter. The patrons surveyed were predominantly male (76 per cent) and aged between 18 and 35 (87 per cent). Average reported alcohol consumption was 7.6 standard drinks for males and 4.9 drinks for females, around double the daily amount recommended by the National Health and Medical Research Council. Further, 23 per cent of the sample had consumed more than 10 drinks (male) and 6 drinks (female). With respect to BALs, 37 per cent of patrons exceeded the drink-drive limit then in force of 0.087 and 56 per cent exceeded 0.05. Of greater concern, 23 per cent who were over the 0.08 legal limit were subsequently observed to drive even though they had been informed of their BAL and legal status with respect to driving. The results suggest that most young patrons drinking in Perth metropolitan hotels and taverns consume alcohol on such occasions in excess of limits currently recommended by health authorities and attain blood alcohol levels dangerous for driving. This is likely to remain unchanged without public debate as to the responsibility of licensees in serving a potentially harmful psychotropic drug and effective enforcement of liquor licensing laws.  相似文献   
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We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene.  相似文献   
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Acute lower limb ischemia secondary to Buerger's disease in a young patient responded to thrombolysis and subsequent popliteal and anterior artery angioplasty. The value of angioplasty in non-limb-threatening ischemia in Buerger's disease has not been established but this case illustrates a role for thrombolysis and angioplasty in acute ischemia.  相似文献   
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