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961.
Pilar Ramírez JoséA. Bonilla Edgardo Moreno Pedro León 《Journal of immunological methods》1983,62(1):15-22
Peroxidase-bound protein A and lectins in combination with precipitable substrates were used to detect viral proteins and glycoproteins on ‘Western blots’. The sensitivity of various methods was compared, including radioiodinated protein A, enzyme immunosorbent assay and peroxidase staining with DAP. The sensitivity of the peroxidase reaction, its rapidity and low cost compared with other methods make this a useful choice for developing protein bands transferred to nitrocellulose paper. In addition, a procedure was devised to clarify and fix nitrocellulose sheets for direct quantification of the precipitated substrate by densitometric analysis. 相似文献
962.
Ronald F. Dodson Pedro Castillo-Mozun L. R. Hieger M. Glenn Williams 《Ultrastructural pathology》1981,2(4):365-372
A muscle biopsy that, by light microscopy, exhibited mild atrophy consistent with chronic denervating disease was submitted for ultrastructural analysis. Inorganic structures within the tissue were defined by energy dispersive analysis as aluminosilicates, magnesium silicates, and iron deposits. These structures were localized in the interstitial (intercollagenous) area and in high concentrations within degenerated muscle bundles. An alteration of the blood/muscle barrier has obviously occurred; however, the extent to which the end result commonly occurs in humans is unknown. Clarification of the question raised by this observation will have to be derived from animal studies, and clinicians must have an awareness of the need for electron microscopy/energy-dispersive x-ray analysis in muscle biopsies from patients with similar therapeutic backgrounds. 相似文献
963.
Several techniques have been advocated for knee arthrodesis, and there has been an increasing interest in modular intramedullary nails in the recent last years. We report a case of femoral and tibial fractures at each end of a modular nail in a solidly fused knee 8 months after an arthrodesis. 相似文献
964.
Barroso-Chinea P Cruz-Muros I Aymerich MS Rodríguez-Díaz M Afonso-Oramas D Lanciego JL González-Hernández T 《The European journal of neuroscience》2005,21(7):1815-1827
Glial cell line-derived neurotrophic factor (GDNF) is a member of the transforming growth factor-beta superfamily that when exogenously administrated exerts a potent trophic action on dopaminergic (DA) cells. Although we know a lot about its signalling mechanisms and pharmacological effects, physiological actions of GDNF on the adult brain remain unclear. Here, we have used morphological and molecular techniques, and an experimental model of Parkinson's disease in rats, to investigate whether GDNF constitutively expressed in the adult mesostriatal system plays a neuroprotective role on midbrain DA cells. We found that although all midbrain DA cells express both receptor components of GDNF (GFRalpha1 and Ret), those in the ventral tegmental area (VTA) and rostromedial substantia nigra (SNrm) also contain GDNF but not GDNFmRNA. The levels of GDNFmRNA are significantly higher in the ventral striatum (vSt), the target region of VTA and SNrm cells, than in the dorsal striatum (dSt), the target region of DA cells in the caudoventral substantia nigra (SNcv). After fluoro-gold injection in striatum, VTA and SNrm DA cells show triple labelling for tyrosine hydroxylase, GDNF and fluoro-gold, and after colchicine injection in the lateral ventricle, they become GDNF-immunonegative, suggesting that GDNF in DA somata comes from their striatal target. As DA cells in VTA and SNrm are more resistant than those in SNcv to intracerebroventricular injection of 6-OHDA, as occurs in Parkinson's disease, we can suggest that the fact that they project to vSt, where GDNF expression is significantly higher than in the dSt, is a neuroprotective factor involved in the differential vulnerability of midbrain DA neurons. 相似文献
965.
da Silva-Júnior FP Braga-Neto P Sueli Monte F de Bruin VM 《Parkinsonism & related disorders》2005,11(7):449-452
We evaluated the effects of amantadine on levodopa-induced dyskinesia (LID) in eighteen consecutive Parkinson's disease (PD) patients in a randomized, double-blind, placebo-controlled study. The primary outcomes were the Clinical Dyskinesia Rating Scale (CDRS) and the Unified Parkinson's Disease Rating Scale (UPDRS) part IVa score changes. The secondary outcomes were the UPDRS II and III score changes. Amantadine did not change the CDRS score for hyperkinesia or dystonia, but decreased the duration of LID and its influence on daily activities (p=0.04) and the UPDRS II score (p=0.01) more than placebo. These findings show that amantadine reduces the duration of LID and improves motor disability in PD. 相似文献
966.
Fernández A García-Segura JM Ortiz T Montoya J Maestú F Gil-Gregorio P Campo P Viaño J 《Dementia and geriatric cognitive disorders》2005,20(2-3):169-177
Whole-head magnetoencephalographic recordings were obtained from 10 patients with Alzheimer's disease (AD) and 10 healthy controls in a resting position. Spectroscopic examinations were performed by means of a 1.5-tesla whole-body scanner in the temporoparietal regions of both hemispheres. The relationship between (1)H-MRS-based and magnetoencephalography (MEG)-based measures and their conjoined capability to improve the diagnosis of AD were investigated in this study. Logistic regression analyses were performed. Three separated logistic models were calculated for (1)H-MRS-based metabolites, low-frequency magnetic activity, and the combination of both measures. A combined myoinositol/N-acetyl aspartate (mI/NAA)-delta dipole density (DD) model predicted the diagnosis with 90% sensitivity and 100% specificity. Additionally, the combination of temporoparietal mI/NAA and delta DD values explained the variability of individuals' cognitive status. The results support the notion that a multidisciplinary approach may improve the understanding and diagnosis of AD. 相似文献
967.
Perez-Cerda C García-Villoria J Ofman R Sala PR Merinero B Ramos J García-Silva MT Beseler B Dalmau J Wanders RJ Ugarte M Ribes A 《Pediatric research》2005,58(3):488-491
We describe three patients, from two Spanish families, with 2-methyl-3-hydroxybutyryl-CoA dehydrogenase (MHBD) deficiency, a recently described X-linked neurodegenerative inborn error of isoleucine metabolism. Two of them are males with severe lactic acidosis suggestive of a mitochondrial encephalopathy, and the third is a female who was less severely affected, suggesting skewed X-inactivation. Molecular studies revealed a new missense mutation, 740A-->G, in one family and a previously described mutation, 388C-->T, in the other, causing the amino acid substitutions N247S and R130C, respectively. Both male patients died, one of them despite treatment with an isoleucine-restricted diet, but the disease has remained stable in the female patient after 1 y of treatment. 相似文献
968.
Poor response to desmopressin acetate (DDAVP) in children with Hermansky-Pudlak syndrome 总被引:1,自引:0,他引:1
Cordova A Barrios NJ Ortiz I Rivera E Cadilla C Santiago-Borrero PJ 《Pediatric blood & cancer》2005,44(1):51-54
BACKGROUND: Hermansky-Pudlak syndrome (HPS) is a common genetic disorder in Puerto Rico. In children with HPS, bleeding is the most disturbing and incapacitating problem. Desmopressin (1-deamino-8-D-arginine vasopressin, (DDAVP)) has been recommended in the management of bleeding disorders characterized by platelet dysfunction, such as HPS. METHODS: Nineteen pediatric Puerto Rican patients with HPS and prolonged bleeding time (BT) were tested for response to administration of DDAVP. RESULTS: Baseline BT was abnormal in 18 (95%) of the patients. The BT following DDAVP administration improved in two cases (11%): one from 7.2 to 5.6 min and the other from 8 to 6 min (Tables II and III). BT measurements remained very prolonged (>15 min) in 17 (89%) of the patients. Patients with the HPS 1 gene mutation had a statistically significant correlation with the poor response following DDAVP (P = 0.03). CONCLUSIONS: DDAVP seldom improves the BT of Puerto Rican children with HPS. Response to DDAVP should be determined individually and platelet transfusion should remain the treatment of choice for a major bleeding episode or surgical procedure. 相似文献
969.
Control of T helper 2 cell function and allergic airway inflammation by PKCzeta 总被引:2,自引:0,他引:2
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Martin P Villares R Rodriguez-Mascarenhas S Zaballos A Leitges M Kovac J Sizing I Rennert P Márquez G Martínez-A C Diaz-Meco MT Moscat J 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(28):9866-9871
Asthma is a disease of chronic airway inflammation in which T helper (Th) 2 cells play a critical role. The molecular mechanisms controlling Th2 differentiation and function are of paramount importance in biology and immunology. PKCzeta has been implicated in the regulation of apoptosis and NF-kappaB, as well as in the control of T-dependent responses, although no defects were detected in na?ve T cells from PKCzeta-/- mice. Here, we report that PKCzeta is critical for IL-4 signaling and Th2 differentiation. Thus, PKCzeta levels are increased during Th2 differentiation, but not Th1 differentiation, of CD4+ T cells, and the loss of PKCzeta impairs the secretion of Th2 cytokines in vitro and in vivo, as well as the nuclear translocation and tyrosine phosphorylation of Stat6 and Jak1 activation, essential downstream targets of IL-4 signaling. Moreover, PKCzeta-/- mice display dramatic inhibition of ovalbumin-induced allergic airway disease, strongly suggesting that PKCzeta can be a therapeutic target in asthma. 相似文献
970.
Pérez-Peñate G Cabrera Navarro P Ponce González M Górriz Gómez E Pulido Duque J García Quintana A Juliá Serdá G 《Respiration; international review of thoracic diseases》2005,72(4):419-422
Inhaled nitric oxide (iNO) has been shown to be a potent and selective vasodilator in pulmonary arterial hypertension (PAH). However, the clinical experience in prolonged treatment is limited. We assess the safety and effectiveness of long-term administration of iNO in severe PAH. Two female patients were admitted to our hospital because of severe dyspnea (World Health Organization functional class IV) and hypoxemia. They were diagnosed with PAH (primary and secondary to congenital heart disease) and treated with iNO for 2 years. The delivery system consisted of an NO tank of 800 ppm, a modified gas-pulsing device, and nasal cannulas. On iNO treatment the patients showed remarkable improvement of symptoms, oxygenation and 6-min walk distance. After 16 months the patients began to experience a progressive rebound of symptoms. A phosphodiesterase type 5 inhibitor (dipyridamole) was added to iNO. This intervention proved useful in improving clinical deterioration and hemodynamics. This is the first study reporting 2-year iNO therapy in 2 patients with primary and secondary pulmonary hypertension. The combination of dipyridamole with iNO augments the pulmonary vasodilatation and may be useful in managing PAH. 相似文献