Previous work has suggested that there may be a widespread disturbance of motor control mechanisms in patients with cervical dystonia. In the present study, we used transcranial magnetic stimulation to investigate the topography of the corticomotor projection to the abductor pollicis brevis (APB) muscle in 10 subjects with idiopathic torticollis. Threshold-adjusted stimuli were delivered at multiple scalp sites during a low-level voluntary contraction of the APB, and maps were generated of motor evoked potential amplitude versus scalp site. The cortical maps for the APB on the side opposite to the direction of head rotation were displaced laterally or posteriorly in all subjects and reverted to a more normal position after botulinum toxin injection of the cervical muscles in 5 subjects. The findings point to a reversible reorganisation of the corticomotor representation of the hand on the same side as the sternocleidomastoid (SCM) muscle that is involved in producing the dystonia. These results provide further evidence for the involvement of cortical centres and for a more widespread abnormality of motor control mechanisms in focal dystonia. The findings also support the notion that head turning is chiefly mediated by the hemisphere ipsilateral to the direction of the head rotation by means of a corticomotor projection to the contralateral SCM. 相似文献
Background: Exercise is an important strategy with potential to improve recovery in older adults following a hip fracture.Purpose: The purpose of this study was to test the impact of a self-efficacy based intervention, the Exercise Plus Program, and the
different components of the intervention, on self-efficacy, outcome expectations, and exercise behavior among older women
post-hip fracture.Methods: Participants were randomized to one of four groups: exercise plus, exercise only, plus only (i.e., motivation), or routine
care. Data collection was done at baseline (within 22 days of fracture), 2, 6, and 12 months post-hip fracture.Results: A total of 209 women were recruited with an average age of 81.0 years (SD=6.9). The majority was White (97.1%), was widowed
(57.2%), and had a high school education (66.7%). Generalized Estimating Equations were used to perform repeated measures
analyses. No differences in trajectories of recovery were observed for self-efficacy or outcome expectations. A statistically
significant difference in the overall trajectory of time in exercise was seen (p<.001), with more time spent exercising in
all three treatment groups.Conclusions: The study demonstrated that it was possible to engage these women in a home-based exercise program and that the plus only,
exercise only, and the exercise plus groups all increased exercise.
Support for this project was provided by National Institute on Aging grants R37 AG09901, R01-AG18668, R01 AG17082, and the
Claude D. Pepper Older Americans Independence Center P60-AG12583. 相似文献
Background: Pathophysiology in the primary sensory neuron may contribute to chronic neuropathic pain. Ca channels play a central role in neuronal processes, and sensory neurons are rich in low-voltage-activated calcium channels (LVACCs). However, the physiologic function of these channels is unknown. Their possible role in rebound burst firing makes them a candidate for increased excitability after neuropathic injury.
Methods: This study uses pharmacological methods to isolate LVACC in cells from the dorsal root ganglia of neuropathic and sham-operated rats, including the blockade of high-voltage-activated Ca channels with fluoride and selective toxins. LVACCs were examined with conventional whole cell patch clamp electrophysiology techniques.
Results: After chronic constriction injury of the peripheral axon, LVACC was significantly reduced compared to sham rats as shown by a 60% reduction in peak current density and an 80% reduction in total calcium influx. A depolarizing shift in the voltage dependence of activation and an increase in the rate of deactivation and inactivation appear to cause this reduction of LVACC. Either Ni2+ or mibefradil, blockers of LVACC, applied in the bath to normal dorsal root ganglion cells during current clamp significantly and reversibly increased excitability. 相似文献
OBJECTIVE: To report on the high incidence of anatomical variants of the origin and course of the internal spermatic vein (ISV) discovered at the time of percutaneous embolization of left varicoceles in a pediatric population. METHODS: We reviewed retrospectively the 65 cases of left varicocele treated by percutaneous embolization (grade II and III) in our institution between 1990 and 2000. The course of the left renal vein (LRV), the origin of the ISV, and the number of ISVs and their pathway were recorded in all cases, according to the B?hren classification. RESULTS: In 37/65 (57%), the ISV was single and arose from a normal LRV (type I). The following variants were encountered: type V--circumaortic LRV 9/65 (14%); type IVb--intrarenal origin of ISV 8/65 (12%); type II--multiple ISV 5/65 (8%); and pelvic collaterals 6/65 (9%). CONCLUSION: Venous anatomical variants are frequently encountered (43%) at the time of left varicocele embolization in children. Such variants often impose some adjustments to the technique of embolization and, at times, hamper the procedure. 相似文献
In conclusion, plasma levels of the endothelialderived vasoconstrictor endothelin-1 (but not those of other neurohormonal vasoconstrictor factors), measured during exercise correlated closely with objective variables of exercise capacity in patients with heart failure. These findings suggest that endothelin-1 may contribute to exercise intolerance in patients with heart failure, perhaps by limiting the ability of the peripheral vasculature to dilate during exercise. 相似文献
This study was carried out to test whether women who think they know when they ovulate, really know. Fifty-three women of age 18.7 to 46.1 (mean age 28.4 years) participated in initial interviews about ovulation. Criteria for recruitment included perceived ovulation, regular menstrual cycles, and not using hormonal contraception. Women collected and refrigerated urine samples from day 5 until they thought they ovulated. Samples collected within 48 h of the perceived signal were then tested for a pre-ovulatory LH surge. Of the 53 original participants, 36 women provided urine samples for 1-6 cycles, so that 87 cycles were tested. Subjective signals of ovulation varied between women and between cycles but included abdominal pain and changes in cervical discharge, libido, and mood. Of the 87 cycles tested, during which women identified one or multiple signals of ovulation, 37 of the 87 urine specimens tested positive for an LH surge for a concordance rate of 42.5%. Using the first tested cycle from the 36 women who provided urine specimens, 13 of those specimens demonstrated an LH surge, for a concordance rate of 36.1%. That rate dropped to 28% (7/25) when women who used basal body temperature as an ovulatory signal were excluded. Finally, the mean level of accuracy among the 15 women who contributed 3-6 urine specimens for testing was 48.9%. The results of this study demonstrate a low degree of concordance between LH surge and perceived ovulation among women who think they know when they ovulate. The most motivated study participants were right about half of the time. Although there is variation among women in their ability to know when they ovulate, this study suggests that, for most women, ovulation is concealed. 相似文献