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61.
OBJECTIVES: To describe functional recovery after surgical resection of low grade gliomas (LGG) in eloquent brain areas, and discuss the mechanisms of compensation. METHODS: Seventy-seven right-handed patients without deficit were operated on for a LGG invading primary and/or secondary sensorimotor and/or language areas, as shown anatomically by pre-operative MRI and intraoperatively by electrical brain stimulation and cortico-subcortical mapping. RESULTS: Tumours involved 31 supplementary motor areas, 28 insulas, 8 primary somatosensory areas, 4 primary motor areas, 4 Broca's areas, and 2 left temporal language areas. All patients had immediate post-operative deficits. Recovery occurred within 3 months in all except four cases (definitive morbidity: 5%). Ninety-two percent of the lesions were either totally or extensively resected on post-operative MRI. CONCLUSIONS: These findings suggest that spatio-temporal functional re-organisation is possible in peritumoural brain, and that the process is dynamic. The recruitment of compensatory areas with long term perilesional functional reshaping would explain why: before surgery, there is no clinical deficit despite the tumour growth in eloquent regions; immediately after surgery, the occurrence of a deficit, which could be due to the resection of invaded areas participating (but not essential) to the function; and why three months after surgery, almost complete recovery had occurred. This brain plasticity, which decreases the long term risk of surgical morbidity, may be used to extend the limits of surgery in eloquent areas.  相似文献   
62.
Recent observations indicate that in thyroparathyroidectomized (TPTX) rats fed a low (0.2 g/100 g) phosphorus diet, the tubular phosphaturic response to parathyroid hormone (PTH) remains markedly blunted even when it is assessed at normal or high plasma concentration and filtered load of inorganic phosphate (Pi). Because 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] decreases the tubular capacity to reabsorb Pi when chronically administered to TPTX rats, we have studied whether this vitamin D(3) metabolite could specifically increase the phosphaturic response to PTH in phosphate-deprived animals. The results show that in Vitamin D-replete TPTX rats fed a low (0.2 g/100 g) phosphorus diet, 1,25(OH)(2)D(3) (2 x 13 pmol/d i.p. for 7 d) markedly enhanced the acute tubular phosphaturic response to PTH (2.5 IU/h i.v.) without affecting the action of the peptide hormone on Ca reabsorption and cyclic-3',5'-AMP excretion. The influence of 1,25(OH)(2)D(3) on the phosphaturic response to PTH could not be ascribed to an increased plasma concentration and(or) filtered load of Pi during the administration of the peptide hormone. However, it could be, at least in part, related to the elevation in the basal level of plasma Pi which was observed in the 1,25(OH)(2)D(3)-treated animals. The results also indicate that 1,25(OH)(2)D(3) significantly enhanced the calcemic response to PTH, which was blunted in these conditions of phosphate deprivation. Unlike 1,25-(OH)(2)D(3), 25-hydroxyvitamin D(3) did not unmask the phosphaturic effect of PTH in phosphate-depleted animals, even when given in doses 100 times larger. Thus, 1,25(OH)(2)D(3) displays a selective and powerful activity in preventing the occurrence of tubular resistance to the phosphaturic action of PTH during Pi depletion. This finding suggests the existence of an important interaction between dietary Pi, 1,25(OH)(2)D(3), and PTH in the homeostasis of phosphate.  相似文献   
63.
64.
Immunohistochemical examination demonstrated widespread granular deposits of alpha-synuclein (alphaSN) in the brains of sheep and goats with natural scrapie, especially in the cornu ammonis and subiculum of the hippocampus; this contrasted with the diffuse and non-granular immunolabelling seen in healthy controls. There was non-regular "co-localization" of PrP(Sc) and alphaSN. The findings resembled those reported in Creutzfeldt-Jakob disease and in experimental prion disease in hamsters and mice. The results suggest that perturbation of alphaSN metabolism plays a role in human and animal prion diseases.  相似文献   
65.
Advances in biology have lead to the characterization of the molecular mechanisms underlying angiogenesis, a crucial process of tumor growth. Tumor cells secrete various growth factors, including VEGF, which activate endothelial cells to form new blood vessels. Numerous drugs, at present in clinical development, interfere with the molecular mediators of angiogenesis. The death of neovessels achieved by some of such compounds allows reduction in tumor size. This review describes many angiogenesic inhibitors which mechanisms of action are quite diverse.  相似文献   
66.
Hrabina M  Dumur JP  Sicard H  Viatte A  Andre C 《Allergy》2003,58(8):808-813
BACKGROUND: Cypress pollen allergy is a major cause of rhinoconjunctivitis and asthma in the Mediterranean area. The nonstandardized cypress allergen extracts currently available for the diagnosis of cypress allergy have a low level of activity. The search for an active material has led to the selection of Juniperus ashei (Ja) pollen because of its very high cross-reactivity with cypress extracts and its superior allergenic activity. The aim of this study was to characterize in vitro and calibrate in vivo an in-house reference extract (IHRS) of J. ashei pollen and determine the specificity and sensitivity of a standardized Ja extract for the prick test diagnosis of cypress allergy. METHODS: Juniperus ashei pollen extract was analysed by 2-D electrophoresis. The IHRS Ja extract was calibrated by skin prick testing in 28 cypress-allergic patients. The sensitivity and specificity of cypress allergy diagnosis using a standardized Ja extract was studied by skin prick test in 42 cypress-allergic patients and 53 nonallergic patients. Jun a 1 content of the IHRS was determined by a monoclonal antibody-based electrophoretic technique. RESULTS: The Jun a 1 content of the 100 IR/ml Ja IHRS extract was 180 microg/ml. For in vivo diagnosis of cypress allergy, Ja pollen extract demonstrated a sensitivity of 95%, a specificity of 100%, a negative predictive value of 96%, and a positive predictive value of 100%. CONCLUSION: Standardized Ja pollen extract is therefore a very appropriate tool for the in vivo diagnosis of cypress pollen allergy and good candidate for specific immunotherapy.  相似文献   
67.
Apoptosis plays a major role in the development of the central nervous system. Previous studies of apoptosis induction during retinal development are difficult to interpret, however, because they explored different mouse strains, different developmental periods, and used different assays. Here, we first established a comprehensive sequential pattern of cell death during the whole development of the C57BL/6J mouse retina, from E10.5 to postnatal day (P) 21 by using the terminal deoxynucleotidyl transferase (TdT) -mediated deoxyuridine triphosphate (dUTP)-biotinylated nick end labeling (TUNEL) assay. We confirmed the existence of three previously described apoptotic peaks and identified another, later peak at P15, in both the outer nuclear layer, in which the photoreceptors differentiate, and the ganglion cell layer. Comparison of wild-type C57BL/6 mice, gld mice, defective in the death ligand fasL, and bax-/- mice, defective in the pro-apoptotic BAX protein, revealed a minor role for FAS ligand but a crucial role for BAX in both apoptosis and normal retinal development. The lack of BAX resulted in thicker than normal inner neuroblastic and ganglion cell layers in adults, with larger numbers of cells and an impaired electroretinogram response related to a decreased number of responsive cells. Our findings indicate that cell death during normal retinal development is important for the modeling of a functional vision organ and showed that the pro-apoptotic BAX protein plays a crucial role in this process.  相似文献   
68.
采用免疫荧光组织化学技术及迷走神经切断术,探讨猪食管一氧化氮类及肽类神经支配的神经化学特性。在光学显微镜下可观察到肌间神经丛及粘膜下神经丛中有部分神经元呈nNOS、VIP、GAL、NPY、PACAP、L-ENK、SP、5-HT及CB免疫阳性,但未见CGRP及SOM阳性神经元。nNOS及CB免疫阳性产物主要分布于不同的神经元胞体内。将PGP9.5作为神经元胞体的标记物,并采用免疫荧光免疫组织化学双重染色方法,分别观察了PGP9.5与nNOS、VIP、SP的双标情况。结果如下:(1)nNOS免疫阳性神经元约占PGP9.5标记神经元总数的63%,而VIP免疫阳性神经元约占36%,SP免疫阳性神经元约占28%;(2)神经节内神经元的平均数量呈现吻尾方向的递增趋势,且食管腹段神经丛内神经节数量明显高于食管其他部位;(3)食管肌层内VIP/GAL/NPY免疫阳性纤维分布最广,其中部分阳性纤维同时呈nNOS或PACAP免疫阳性;SP和/或L-ENK免疫阳性纤维在粘膜肌层的分布明显多于平滑肌层。CGRP阳性纤维非常少见,这一点不同于对其他动物的观察结果;(4)经一侧迷走神经切断后,肌间神经丛内PACAP及5-HT免疫阳性纤维明显减少,提示这些纤维可能来源于迷走神经;而平滑肌中VIP/GAL/NPY和/或nNOS免疫阳性纤维数量未发现明显变化,可能为内源性来源。  相似文献   
69.
BACKGROUND: Persistent organochlorine pollutants (POP) may affect both the female and male reproductive system in animals as well as in humans. METHODS: Blood samples were collected from pregnant women and their partners from Greenland, Warsaw and Kharkiv, and from a cohort of Swedish fishermen's wives. Blood samples were analysed for 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE). Information on the participants' fertility, measured as time to pregnancy (TTP), was collected. In total, 778 men and 1505 women were included in the analyses. RESULTS: The data from Warsaw, Kharkiv and the Swedish fishermen's wives indicated no effect of either male or female exposure to POP on TTP. However, among men and women from Greenland, there seemed to be an association between serum concentrations of CB-153 and p,p'-DDE and prolonged TTP. Due to the strong intra-individual correlation between CB-153 and p,p'-DDE in the Greenlandic population, it was not possible to determine whether the risk was associated with CB-153 or p, p'-DDE or was an interaction between the two compounds. CONCLUSIONS: The overall results of the present study create a somewhat ambiguous pattern, but give some support to the idea that dietary POP exposure might be harmful for couple fertility.  相似文献   
70.
BACKGROUND: Cytokeratin immunohistochemistry (IHC) reveals a higher rate of occult lymph node metastases among lobular carcinomas than among ductal breast cancers. IHC is widely used but is seldom recommended for the evaluation of sentinel lymph nodes in breast cancer patients. Objective: To assess the value of cytokeratin IHC for the detection of metastases in sentinel lymph nodes of patients with invasive lobular carcinoma. METHODS: The value of IHC, the types of metastasis found by this method, and the involvement of non-sentinel lymph nodes were analysed in a multi-institutional cohort of 449 patients with lobular breast carcinoma, staged by sentinel lymph node biopsy and routine assessment of the sentinel lymph nodes by IHC when multilevel haematoxylin and eosin staining revealed no metastasis. RESULTS: 189 patients (42%) had some type of sentinel node involvement, the frequency of this increasing with increasing tumour size. IHC was needed for identification of 65 of these cases: 17 of 19 isolated tumour cells, 40 of 64 micrometastases, and 8 of 106 larger metastases were detected by this means. Non-sentinel-node involvement was noted in 66 of 161 cases undergoing axillary dissection. Although isolated tumour cells were not associated with further lymph node involvement, sentinel node positivity detected by IHC was associated with further nodal metastases in 12 of 50 cases (0.24), a proportion that is higher than previously reported for breast cancer in general. CONCLUSIONS: IHC is recommended for the evaluation of sentinel nodes from patients with lobular breast carcinoma, as the micrometastases or larger metastases demonstrated by this method are often associated with a further metastatic nodal load.  相似文献   
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