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1.

Objectives

To investigate whether functional overreaching affects locomotor system behaviour when running at fixed relative intensities and if any effects were associated with changes in running performance.

Design

Prospective intervention study.

Methods

Ten trained male runners completed three training blocks in a fixed order. Training consisted of one week of light training (baseline), two weeks of heavy training designed to induce functional overreaching, and ten days of light taper training designed to allow athletes to recover from, and adapt to, the heavy training. Locomotor behaviour, 5-km time trial performance, and subjective reports of training status (Daily Analysis of Life Demands for Athletes (DALDA) questionnaire) were assessed at the completion of each training block. Locomotor behaviour was assessed using detrended fluctuation analysis of stride intervals during running at speeds corresponding to 65% and 85% of maximum heart rate (HRmax) at baseline.

Results

Time trial performance (effect size ±95% confidence interval (ES): 0.16 ± 0.06; p < 0.001), locomotor behaviour at 65% HRmax (ES: ?1.12 ± 0.95; p = 0.026), and DALDA (ES: 2.55 ± 0.80; p < 0.001) were all detrimentally affected by the heavy training. Time trial performance improved relative to baseline after the taper (ES: ?0.16 ± 0.10; p = 0.003) but locomotor behaviour at 65% HRmax (ES: ?1.18 ± 1.17; p = 0.048) and DALDA (ES: 0.92 ± 0.90; p = 0.045) remained impaired.

Conclusions

Locomotor behaviour during running at 65% HRmax was impaired by functional overreaching and remained impaired after a 10-day taper, despite improved running performance. Locomotor changes may increase injury risk and should be considered within athlete monitoring programs independently of performance changes.  相似文献   
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Ninety-seven inpatients with tardive dyskinesia (average AIMS score = 13), the majority of whom were schizophrenic, were studied. Forty patients were Caucasian, and 57 were African-American. The APOE genotypes of these patients were compared to previously published genotypes of controls and with previously published studies of APOE genotypes in patients with schizophrenia. There were no significant differences in APOE allele frequencies comparing the African-American tardive dyskinesia population and the African-American control groups. In contrast, significant (< 0.05) P values were obtained comparing the Caucasian tardive dyskinesia population to the Caucasian controls, when comparing allele frequencies and genotypic frequencies. This study suggests that Caucasians bearing an APOE2 allele are at increased risk of developing tardive dyskinesia, whereas African-Americans are not. APOE genotype-specific risks of both tardive dyskinesia and Alzheimer's disease that vary across populations could be due to recruitment of patients or controls or could be due to modifying effects of differing genetic or environmental backgrounds. The mechanism by which the APOE2 allele increases risk of tardive dyskinesia is not known. Further information about the mechanisms of increased risk of tardive dyskinesia could result in stratification of prescribing practices weighing the costs of medications against the relative risk of side effects.  相似文献   
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BACKGROUND: Obsessive-compulsive disorder (OCD) is a chronic, impairing and often comorbid disorder. METHODS: 1000 subjects who called the Anxiety Disorders Association of America (ADAA) were surveyed and divided in three groups: (a) callers with OCD (OCD) and two overlapping control groups: (b) callers with no axis I disorder (NAC) and (c) with no-OCD (NOC) using a 97-item questionnaire. RESULTS: The rate of OCD was 14.5% (N = 145). Relative to the NOC group, OCD subjects were more likely to be female, White, younger and not married. Relative to the NAC group, subjects with OCD were more likely to be White, not married and younger. OCD was accompanied by significant comorbidity and was associated with an increased number of visits to health professionals than NAC subjects. There was no significant difference regarding unemployment rates among the three groups. However, OCD callers were more likely than both control groups to have missed work or have decreased productivity due to their mental condition. OCD subjects took an average of 1 psychotropic medication in the past year and were statistically more likely than the control groups to experience sleepiness and nervousness as side effects. CONCLUSIONS: OCD was fairly prevalent among ADAA callers and presented high levels of comorbidity, impairment, health care utilization and sensitivity to psychotropic side effects.  相似文献   
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BACKGROUND: The relationship between the circumstances and severity of closed head injury (CHI) and the clinical and imaging features of cranial nerve 3, 4, and 6 palsies has not been rigorously addressed in a large study. METHODS: Retrospective chart review of 210 consecutive patients with CHI examined at a single tertiary care center from 1987 to 2002. Patients were located by searching the ophthalmology inpatient consultation and neuro-ophthalmology outpatient databases and hospital emergency room billing codes for a diagnosis of traumatic 3, 4, or 6 cranial nerve palsy (Cranial Nerve Injury Group) and a diagnosis of CHI without traumatic 3, 4, or 6 nerve palsy (Control Group). The Cranial Nerve Injury Group was then subdivided into two groups: those with injuries to an individual cranial nerve and those with multiple (including bilateral) cranial nerve injuries. Comparisons between groups were based on age, gender, type of accident, Glasgow Coma Scale (GCS), documented loss of consciousness (LOC), type of ocular injury, presence of systemic injury, need for rehabilitation, physical therapy and cognitive scores, and imaging features. RESULTS: The Cranial Nerve Injury Group had a significantly higher severity of head injury, more CT abnormalities, and worse short-term neurologic outcomes as compared with the Control Group. These trends were also found when each cranial nerve injury subgroup was compared with the Control Group. Those with cranial nerve 3 palsy had the most severe head injury; those with cranial nerve 4 palsy had an intermediate level of head injury; and those with cranial nerve 6 palsy had the lowest level of head injury. There were no consistent associations between the location of the imaging abnormalities and which cranial nerve was damaged. CONCLUSIONS: CHI with palsy of an ocular motor nerve was more severe than CHI without ocular motor nerve palsy, as measured by the GCS, intracranial and skull imaging abnormalities, and a greater frequency of inpatient rehabilitation. Palsy of cranial nerve 3 was associated with relatively more severe CHI than was palsy of cranial nerves 4 or 6. The location of the imaging abnormalities did not correlate with a particular cranial nerve injury.  相似文献   
8.
This study examined the feasibility of isolating and transferringthe centrosome-containing region of spermatozoa to mature humanoocytes. The findings demonstrate that individual sperm centrosomescan be transferred and are capable of nucleating maternal tubulinto form a well-developed sperm aster in the recipient oocyte.The results are discussed with respect to centrosome functionin early human development and applications in clinical in-vitrofertilization in the treatment of certain forms of male factorinfertility.  相似文献   
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Summary Squamous cell carcinoma of the head and neck is a disease predominantly of males and is due to a variety of known environmental irritants, notably cigarette smoke. Dietary, viral and immunological factors may also be relevant. Head and neck squamous cancers express epidermal growth factor receptors and some show weak levels of oestrogen receptor activity, but a reliable serum marker of tumour burden remains to be identified. The prognosis is found to be less favourable in females, in those with advanced T stage, in association with multiple node involvement, especially where extracapsular spread is present and where the T4/T8 ratio is elevated. Administration of heterologous blood during therapy may also have an adverse effect on prognosis. Interested clinicians must remember that most cases are preventable. Correspondence to: A.G.D. Maran  相似文献   
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