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Sensitivity of laser-evoked potentials versus somatosensory evoked potentials in patients with multiple sclerosis. 总被引:11,自引:0,他引:11
J?rg Spiegel Christiane Hansen Ulf Baumg?rtner Hanns Christian Hopf Rolf Detlef Treede 《Clinical neurophysiology》2003,114(6):992-1002
OBJECTIVE: Somatosensory evoked potentials (SEPs) play a less important role in the diagnosis of multiple sclerosis (MS) than visually evoked potentials. Since standard SEPs only reflect the dorsal column function, we now investigated spinothalamic tract function in patients with MS using laser-evoked potentials (LEPs). METHODS: LEPs to thulium laser stimuli (3ms, 540 mJ, 5mm diameter) were recorded from 3 midline positions (Fz, Cz, Pz) in 20 patients with MS, and 6 patients with possible but unconfirmed MS. Peak latencies and peak-to-peak amplitude of the vertex potential negativity (N2) and positivity (P2) were evaluated and compared with normative values from 22 healthy control subjects. Median and tibial nerve SEPs were recorded with standard methods. Depending on the results of sensory testing, two skin areas (both hands, both feet, or one hand and foot of the same body side) were assessed in each patient. RESULTS: In group comparisons, LEPs in patients with MS were significantly delayed and reduced in amplitude compared with healthy subjects (P<0.001) or patients with suspected but unconfirmed MS (P<0.05). In intraindividual comparisons within the patients with MS, LEP amplitude was significantly lower (P<0.01) and latencies were significantly longer (N2: P<0.01; P2: P<0.05) for a clinically hypoalgesic skin area than an unaffected control area. On a single case basis, LEPs were abnormal in 12 (60%) and SEPs in 8 (40%) of the patients with MS; combined analysis of LEPs and SEPs raised sensitivity to 75% (15 patients). LEPs were also abnormal for 7 skin areas with clinically normal nociception and thermal sensitivity, indicating subclinical lesions. Standard SEPs detected subclinical lesions in 5 areas with normal tactile sensitivity. CONCLUSIONS: In patients with multiple sclerosis, spinothalamic tract function and LEPs were impaired more often than dorsal column function and SEPs. LEPs also detected subclinical lesions. Combined assessment of LEPs and SEPs can help to document dissemination of demyelinating CNS lesions and thus contribute to the diagnosis of multiple sclerosis. 相似文献
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Early nerve regeneration after Achilles tendon rupture — a prerequisite for healing? A study in the rat 总被引:4,自引:0,他引:4
Paul W Ackermann Mahmood Ahmed Andris Kreicbergs 《Journal of orthopaedic research》2002,20(4):849-856
Nerve regeneration during healing of Achilles tendon rupture in the rat was studied by immunohistochemistry including semi-quantitative assessment. Neuronal markers for regenerating and mature fibers, ie., growth associated protein 43 (GAP-43) and protein gene product 9.5 (PGP 9.5), respectively, were analyzed at different time points (1-16 weeks) post-rupture. In the paratenon, both the ruptured and intact contralateral tendon (control) consistently exhibited immunoreactivity to the two neuronal markers. However, in the proper tendinous tissue only the ruptured tendon showed immunoreactivity to GAP-43 and PGP 9.5. This expression was seen already at week 1 post-rupture to reach a peak at week 6 followed by a successive drop till week 16. Also the occurrence of sensory and autonomic fibers according to immunoreactivity for calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY), respectively, was analyzed. CGRP-positivity was abundantly seen from weeks 2-6 in both perivascular and sprouting free nerve endings in the proper tendon tissue undergoing healing. NPY appeared later, at weeks 6-8 post-rupture around blood vessels mainly located in the surrounding loose connective tissue. Apart from a role in vasoaction (CGRP, vasodilatory; NPY, vasoconstrictory). both neuropeptides have been implicated in fibroblast and endothelial cell proliferation required for angiogenesis. The present study shows that early healing of ruptured tendons is characterized by an orchestrated, temporal appearance of nerve fibers expressing peptides with different actions. The observed pattern of neuronal regeneration and neuropeptide expression may prove to be important for normal connective tissue healing. 相似文献
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H W Losken W M Morris P B Uys J W Earle P A Le Roux E Ackermann 《Suid-Afrikaanse tydskrif vir geneeskunde》1988,73(10):575-577
Trauma to the orbital region may result in fractures of the bony orbit, displacement of which gives rise to malposition of the eye and diplopia. If initial treatment is not feasible or is unsuccessful, later correction may be achieved by osteotomy or reduction and stabilisation of the bony fragments, often with bone grafts. Displaced medial or lateral canthi may need to be repositioned, where feasible in an overcorrected position. Where bone grafts are necessary, the skull is now favoured as the best donor site. 相似文献
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H. -W. Ackermann P. Auclair S. Basavarajappa H. P. Emadi Konjin C. Savanurmath 《Archives of virology》1994,137(1-2):185-190
Summary Preparations of silkworm larvae contained two large phages with contractile tails (Myoviridae). One phage was active onPseudomonas paucimobilis. The other, not cultivated, was one of the largest viruses known. 相似文献
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Dr. med. et med. dent. Hanns Schmidt 《European archives of oto-rhino-laryngology》1923,110(4):266-281
Ohne ZusammenfassungMit 8 Abbildungen 相似文献
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Hess B; Hasler-Strub U; Ackermann D; Jaeger P 《Nephrology, dialysis, transplantation》1997,12(7):1362-1368
BACKGROUND: Metabolic evaluation in recurrent idiopathic calcium renal
stone-formers (RCSF) was analysed with respect to the following questions:
(1) do three 24-h urines provide more diagnostic accuracy in the metabolic
evaluation of RCSF than 1 or 2 urines?; (2) does time after stone event
influence the diagnostic yield?; (3) is urine composition at weekends
different from that at mid-week?; (4) what are the prevalences of the most
important risk factors (RF) of idiopathic calcium nephrolithiasis, i.e. low
volume (LV), hypercalciuria (HC), hyperoxaluria (HO), hyperuricosuria (HU),
hypocitraturia (Hypo-Cit), and hypomagnesiuria (Hypo-Mg)?; and (5) do male
RCSF differ from females with respect to urinary RFs? METHODS: Seventy-five
RCSF (59 men, 16 women) collected three 24-h urines (U1-3) while on
free-choice diet. To account for possible variations in lifestyle and diet,
U1 and U3 had to be collected midweek and U2 at a weekend. RESULTS: When
considering all three urines together (U1 + U2 + U3), the number of RF
abnormalities/patient was 2.8 +/- 0.1, higher than numbers of any
combination of two urines or of any single urine (P = 0.0001 for all
comparisons). The number of RF abnormalities also rose with time after
stone event, from 0.8 +/- 0.1 (range 0-4) in U1 to 1.1 +/- 0.1 (range 0- 4)
in U3 (P = 0.011 vs U1). Whereas all other RF did not change between
collections, urine volume was lower in U2 (1793 +/- 90 ml) than in U1 (2071
+/- 97 ml, P = 0.0001 vs U2) and U3 (1946 +/- 97 ml, P = 0.046 vs U2). At
least 1 abnormality was found in 85.3% of all RCSF, and multiple
abnormalities occurred in 47%. The most frequent RF was HC (39%), followed
by HO and LV (32% each), Hypo-Cit (29%), HU (23%) and Hypo-Mg (19%). Males
more often had Hypo-Cit (P < 0.001) and Hypo-Mg (P < 0.01) than
females, whereas HO was more frequent in female RCSF (P < 0.025 vs
males). CONCLUSIONS: Diagnostic accuracy of metabolic evaluation in RCSF
increases both with the number of urines collected and the time passing
after a stone event. Urines collected at weekends differ from those of the
week only by their lower volumes. Abnormalities of RF for calcium
nephrolithiasis can be detected in 85.3% of RCSF, and HC is the most common
RF both in male and female RCSF.
相似文献
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