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排序方式: 共有2661条查询结果,搜索用时 88 毫秒
1.
Matthieu Talagas Nicolas Lebonvallet Franois Berthod Laurent Misery 《Experimental dermatology》2019,28(12):1466-1469
Recent years have brought an enhanced understanding of keratinocyte contribution to cutaneous nociception. While intra‐epidermal nerve endings were classically considered as the exclusive transducers of cutaneous noxious stimuli, it has now been demonstrated that epidermal keratinocytes can initiate nociceptive responses, like Merkel cells do for the innocuous mechanotransduction. In the light of recent in vivo findings, this article outlines this paradigm shift that points to a not yet considered population of sensory epidermal cells. 相似文献
2.
Electrical resistance and macromolecular permeability of brain endothelial monolayer cultures 总被引:8,自引:0,他引:8
Electrophysiological measurements were made on endothelial cells initially isolated as individual clones from bovine brain microvessels, and then grown as monolayers on a permeable support of glutaraldehyde-treated collagen gel. When transendothelial cell resistance (R) of the clones was measured, there was a range of values from a low of 157.4 +/- 4.5 omega.cm2 (n = 6) to a high of 783.2 +/- 7.0 omega.cm2 (n = 34). With the high-resistance cells, there was also a small potential difference of -0.46 +/- 0.03 mV luminal-side negative (n = 34). In comparison, endothelial cells from bovine aortas and rat epididymal fat pads cultured on the collagen gels had transendothelial R values of 13.5 +/- 0.2 (n = 62) and 0.45 +/- 0.03 (n = 10) omega.cm2, respectively. Exposure of the high-resistance brain endothelial cell monolayers to a Ca2+-free medium for 10 min decreased the R to 75% of the control values. Addition of Ca2+ back to the medium caused a return of the transendothelial R to control values within 1 h. Endothelial cells were also grown to confluency on microcarrier beads for permeability measurements to Evans blue dye-bovine serum albumin. Microcarriers with no cells (control) and microcarriers with bovine and epididymal endothelial cell monolayers showed no difference in the amount of adsorbed dye. Microcarriers with brain endothelial monolayers excluded up to 80% of the dye. This mammalian brain endothelial culture system will be a useful model for studies of the electrophysiological and permeability properties of the blood-brain barrier. 相似文献
3.
4.
J. H. Meier Dr. W. L. C. Rutten H. B. K. Boom 《Medical & biological engineering & computing》1995,33(3):409-417
Experimentally, during electrical nerve stimulation, the influence is examined of two intrafascicular anodes on the force
recruitment with one intrafascicular cathode. It is found that the anodes suppress recruitment and that this effect is more
pronounced when the distance of the anodes to the cathode is decreased, or when the anodal currents are increased. The measured
recruitment curve patterns can be qualitatively explained by a nerve stimulation model that calculates theoretical recruitment
curves for intrafascicular multi-electrode configurations. Discrepancies between the experimental and the theoretical recruitment
curves are seen, but these can be understood by taking into account a non-uniform fibre distribution. 相似文献
5.
The study described in this paper was primarily conducted toidentify the cell types involved in the formation, progressionand regression of metaplastic changes in the respiratory tractepithelium of hamsters after intratracheal intubations withbenzo[a]pyrene Furthermore, the role of vitamin A and ß;-carotenein these processes was studied. In the course of the study aremarkable effect of dietary ß;-carotene on survivalof hamsters became a subject of investigation. Hamsters werefed diets with various levels of vitamin A or ß-caroteneand were treated intratracheally with a suspension of benzo[a]pyrenewith ferric oxide in saline. The tumour response of the respiratorytract was very low (2.8%) and hyper- and metaplasia of respiratoryepithelium were virtually absent. However, an interesting observationwas an exceptionally low mortality of only 2% after 69 weeksin the group of hamsters fed a high ß-carotene diet(1% w/w), whereas in the other groups mortality after 69 weeksamounted to 25%. Although the exact cause of death of most ofthe hamsters could not be established, a 40% reduction of lipidperoxidation in the livers was found in the high ß-carotenegroup. Moreover, In this group the degree and incidence of nephroslsand of focal mineralization of kidneys and heart were lowerthan in the other groups. These favourable effects of the highß-carotene diet may have contributed to the unusuallyhigh survival rate in hamsters fed this diet. Further studiesare planned to verify and study this observation. 相似文献
6.
Michael J. Rutten 《Methods in Cell Science》1992,14(4):235-245
Summary The adherence, growth, and electrophysiologic properties of guinea pig gastric mucous epithelial cells were investigated using porous membrane filters. We also tested three commercially available Ussing-type chambers that were designed to be used with the various porous membrane supports. Overall, the 0.45-µm Falcon-Cyclopore porous membrane was found to be very favorable for the consistent attachment and growth of our cells. This same filter also gave good results in the detection of periodic acid Schiff-positive mucous glycoprotein and Nile red neutral lipid fluorescence in the gastric mucous cells. Our cells grew poorly on collagen-coated Costar-Snapwells and Millipore Millicell-CM porous filters. For measurement of transepithelial potential difference resistance, and short-circuit current, the Costar-Snapwell with the Costar-Snapwell Diffusion-chamber system was superior in design and operation when compared to the Costar Transwell-COL, Falcon-Cyclopore, or Anotec-Anocell porous inserts used with conventional Ussing-chambers. The gastric mucous cells grew best on ICN-Cellagen membranes, but these filters routinely detached from their plastic holder and therefore could not be used for Ussing-chamber studies. The large 24.5-mm, 0.40-µm pore size Costar-Transwell-COL and the 24.1-mm, 0.45-µm Falcon-Cyclopore membranes gave good results when used in a modified horizontal-chamber for microelectrode analysis of membrane potentials and resistances of the gastric mucous cell monolayers. 相似文献
7.
Three cases of acrocephalosyndactyly with duplication of the first toe and presence of six well-individualized metatarsals are reported. This type of polysyndactyly should suggest the diagnosis of Carpenter syndrome, which is inherited on a recessive autosomal basis. However, in the three patients reported here, the facial dysmorphism was distinct from that seen in Carpenter syndrome and the syndactyly was more marked. The correct diagnosis therefore seems to be Apert acrocephalosyndactyly, a disease with dominant transmission. A mutation seems very likely and consequently the risk of recurrence in siblings is probably minimal. 相似文献
8.
Matthieu Eveillard Patrice Mertl Blaise Tramier Fran?ois Eb 《Infection control and hospital epidemiology》2003,24(10):778-780
Effectiveness of gentamicin-impregnated cement in preventing deep wound infection after total knee arthroplasty (TKA) was estimated using data from prospective surveillance. In multivariate analysis, the protective effect of gentamicin-impregnated cement on the development of infection was close to the limit of significance. Gentamicin-impregnated cement may prevent TKA infections. 相似文献
9.
Matthieu Vinchon Patrick Dhellemmes Emmanuelle Laureau Gustavo Soto-Ares 《Child's nervous system》2007,23(8):839-845
INTRODUCTION: Spinal cord compression due to meningeal thickening is a rare occurrence in shunted patients. Because of the long delay to clinical onset, this complication has not been identified as yet. AIMS: We report on nine cases of shunt-related progressive myelopathy due to meningeal thickening (SPMMT). MATERIALS AND METHODS: We reviewed our database of shunted children, for cases having developed progressive tetraparesis due to cervical meningeal thickening. RESULTS: We identified nine observations of SPMMT, eight of these with hydrocephalus due to neonatal meningitis; the last case had Dandy-Walker malformation shunted at birth and suffered postoperative meningitis. The age of clinical onset of myelopathy was between 6 and 20 years (median 12.8). All patients presented with slowly progressive walking difficulties with falls and no spinal pain. Magnetic resonance imaging (MRI) showed typically a thickened dura mater with collapse of the arachnoid space, compensatory expansion of the epidural fat, and T2 hyperintensity in the spinal cord. We operated on seven patients for surgical decompression and arachnoidolysis: One died postoperatively because of shunt malfunction, and two others died later of complications of tetraplegia. Three patients were aggravated after surgery, three experienced partial improvement, but one of these subsequently deteriorated again. CONCLUSION: SPMMT appears to be a novel and well-defined clinical and pathological entity; its pathological and radiological features are stereotyped; however, the diagnosis is delayed because of the slow pace of the disease. Although surgical decompression may be the only option, its results were poor in our experience; earlier surgery might improve this grim prognosis. 相似文献
10.
Treatment of motoneuron degeneration by intracerebroventricular delivery of VEGF in a rat model of ALS 总被引:18,自引:0,他引:18
Storkebaum E Lambrechts D Dewerchin M Moreno-Murciano MP Appelmans S Oh H Van Damme P Rutten B Man WY De Mol M Wyns S Manka D Vermeulen K Van Den Bosch L Mertens N Schmitz C Robberecht W Conway EM Collen D Moons L Carmeliet P 《Nature neuroscience》2005,8(1):85-92
Neurotrophin treatment has so far failed to prolong the survival of individuals affected with amyotrophic lateral sclerosis (ALS), an incurable motoneuron degenerative disorder. Here we show that intracerebroventricular (i.c.v.) delivery of recombinant vascular endothelial growth factor (Vegf) in a SOD1(G93A) rat model of ALS delays onset of paralysis by 17 d, improves motor performance and prolongs survival by 22 d, representing the largest effects in animal models of ALS achieved by protein delivery. By protecting cervical motoneurons, i.c.v. delivery of Vegf is particularly effective in rats with the most severe form of ALS with forelimb onset. Vegf has direct neuroprotective effects on motoneurons in vivo, because neuronal expression of a transgene expressing the Vegf receptor prolongs the survival of SOD1(G93A) mice. On i.c.v. delivery, Vegf is anterogradely transported and preserves neuromuscular junctions in SOD1(G93A) rats. Our findings in preclinical rodent models of ALS may have implications for treatment of neurodegenerative disease in general. 相似文献