| 1. |
|
|
| 2. |
- Lindvall, O, et al.
(författare)
-
Human fetal dopamine neurons grafted into the striatum in two patients with severe Parkinson's disease. A detailed account of methodology and a 6-month follow-up
- 1989
-
Ingår i: Archives of Neurology. - : American Medical Association (AMA). - 0003-9942. ; 46:6, s. 31-615
-
Tidskriftsartikel (refereegranskat)abstract
- By using stereotaxic surgical techniques, ventral mesencephalic tissues from aborted human fetuses of 8 to 10 weeks' gestational age were implanted unilaterally into the striata in two patients with advanced Parkinson's disease. The patients were treated with a cyclosporine, azathioprine, and steroid regimen to minimize the risk for graft rejection. They were examined for 6 months preoperatively and 6 months postoperatively and continued to receive the same doses of antiparkinsonian medication. There were no significant postoperative complications. No major therapeutic effect from the operation was observed. However, in the clinical tests, both patients showed small but significant increases of movement speed for repeated pronation-supination, fist clenching, and foot lifting. The rate of walking also increased in the one patient tested. For both patients, there was an initial worsening postoperatively, followed by improvement vs preoperative performance at 1 to 3 months. Both patients also showed significant improvement in the magnitude of response to a single dose of levodopa (L-dopa), but there was no increase in the duration of drug action. The motor readiness potential increased in both patients postoperatively, primarily over the operated hemisphere. Neurophysiological measurements also showed a more rapid performance of simple and complex arm and hand movements on the side contralateral to transplantation in one patient at 5 months postoperatively. Positron emission tomography demonstrated no increased uptake of 6-L-(18F)-fluorodopa in the transplanted striatum at 5 and 6 months. Taken together, these results suggest that the fetal nigral implants may have provided a modest improvement in motor function, consistent with the presence of small surviving grafts. Although our results support further scientific experimentation with transplantation in Parkinson's disease, widespread clinical trials with this procedure are probably not warranted at this time.
|
|
| 3. |
- Rothwell, P.L., et al.
(författare)
-
A new model for auroral breakup during substorms
- 1989
-
Ingår i: IEEE Transactions on Plasma Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0093-3813 .- 1939-9375. ; 17, s. 150-157
-
Tidskriftsartikel (refereegranskat)
|
|
| 4. |
|
|
| 5. |
- Rothwell, P.L., et al.
(författare)
-
Substorm breakup on closed field lines
- 1988
-
Ingår i: Advances in Space Research. - : Elsevier BV. - 0273-1177. ; 8, s. 347-350
-
Tidskriftsartikel (refereegranskat)abstract
- This model explains why breakup has been observed as low as L = 5-6 and predicts that a higher concentration of O+ in the plasma sheet will permit breakup at such low L values. It is argued that the establishment of a coupled current structure within a single arc leads to a quasi-stable system i.e. the pre-breakup regime. Perturbation of the pre-breakup structure leads to an instability criterion. Certain quiescent configurations are inherently unstable. Thus transitions from a stable to an unstable situation can trigger a rapid poleward expansion of the quiescent arc or substorm breakup. In our model the kinetic energy of injected plasma from the magnetotail supplies the energy for breakup. © 1989.
|
|
