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81.
André A Tessier C Brétillon L Sébédio JL Chardigny JM 《Brain research. Molecular brain research》2005,136(1-2):142-147
In situ hybridization can be carried out using different methods. The experimenter has to choose various parameters: the type of tissue fixation, the time of incubation, and the duration of the exposure time. All these parameters are determinant for the sensitivity and the resolution of this technique. This publication of technical aspects described different experiments performed for in situ hybridization on liver tissue. We may conclude on the parameters to optimize each step of the hybridization procedure. Moreover, this technique could be transposed to the brain and applied to little structures with a light expression of DHAP-AT. 相似文献
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83.
Several assays are available for testing nuclear quality of spermatozoa, many of them allowing to define a DNA fragmentation index (DFI). Numerous recent studies on this subject agree on several points: negative correlations are observed between DFI and sperm characteristics. Concerning the relationships between DFI and artificial reproductive technologies, there are some disagreements about correlations between DFI and fertilization rates; conversely, in case of high DFI, both blastocyst formation rate and pregnancy rate are significantly reduced. Several authors have defined a threshold value for DFI, corresponding to an absence of pregnancy, or a very low pregnancy rate, for samples above this value. Unfortunately, there are no data available concerning the relationships between sperm DNA quality and abnormalities at birth. 相似文献
84.
Söderman AC Möller J Bagger-Sjöbäck D Bergenius J Hallqvist J 《The Laryngoscope》2004,114(10):1843-1848
BACKGROUND: Menière's disease is defined as the presence of recurrent, spontaneous episodic vertigo, hearing loss (HL), aural fullness, and tinnitus. The occurrence of attacks is unpredictable. The etiology is still unknown, but the disease has a pathologic correlate in hydropic distension of the endolymphatic system. Earlier studies have shown increased incidence of stress on the same day as vertigo attacks, but it has not been determined whether stress occurring on the day of the vertiginous episode came before or after the onset of the vertigo. METHODS: A case-crossover study including 46 patients with active Menière's disease. MAIN OUTCOME MEASURE: Relative risks with 95% confidence intervals (CI). FINDINGS: During the study period, 153 Menière's attacks were reported. Twenty-four (52%) of the 46 patients reported attacks. Twelve of the 153 (8%) attacks occurred within 3 hours after exposure to emotional stress. The relative risk of having an attack was 5.10 (95% CI 2.37-10.98) during 3 hours after being exposed to emotional stress. Twenty-nine percent of the patients with attacks had at least one attack after exposure to emotional stress. For mental stress, the relative risk was 4.16 (95% CI 1.46-11.83) and the hazard period 1 hour, but only five attacks were exposed. No excess risk was found after physical stress. INTERPRETATION: Being exposed to emotional stress increases the risk of getting an attack of Menière's disease during the next hour, and the hazard period is possibly extended up to 3 hours. 相似文献
85.
Recent studies have indicated that nitric oxide (NO)-induced cGMP synthesis is involved in different steps of neurogenesis in invertebrates. The development of putative NO synthetising elements was described earlier in the embryonic and juvenile pond snail, Lymnaea stagnalis, applying NADPH-diaphorase histochemistry (Serfz et al., 1998). In the present study, we examined the distribution of NO synthase (NOS) during Lymnaea development by in situ hybridization for Lymnaea-NOS mRNA, histochemical, and immunohistochemical techniques for the NOS and NO-stimulated cGMP. Peripheral fibers projecting to the CNS and terminating in the ganglionic neuropils showed NOS immunoreactivity from 85% of embryonic development. At the same time, a fine dot-like, immunostaining indicated the presence of cGMP in the neuropil area. In the CNS, Lymnaea-NOS mRNA positive, as well as NOS and cGMP immunoreactive perikarya were detected first during postembryonic development; their number significantly increased from P3 juvenile stage. Some of the cell groups in the CNS containing NOS immunoreactive material also displayed Lymnaea-NOS mRNA hybridization signal and were cGMP-positive. However, in the subesophageal ganglia, the distribution of Lymnaea-NOS mRNA positive cell groups did not correspond to that of the NOS immunoreactive cells. Neurons revealing transient NOS and cGMP immunoreactivity, respectively, could also be detected in this part of the CNS. In most of the ganglia the number of Lymnaea-NOS mRNA containing and cGMP immunopositive neurons, respectively, exceeded that of the NOS immunoreactive cells from P4 juvenile stage. The localization of NADPH-diaphorase reaction also correlated well with that of the NOS immunoreactivity in the developing CNS. At the periphery, colocalization of Lymnaea-NOS mRNA signal, NOS and cGMP immunoreactivities were observed in the epithelial cells of the esophagus and mantle after hatching. The findings suggest the functional maturity of the NO/cGMP signal transduction pathway at both central and peripheral levels during the development of the snail, Lymnaea stagnalis. The differences in the localization of Lymnaea-NOS mRNA labeling and NOS immunoreactivity in the CNS and PNS can be explained by the existence of different NOS isoforms, posttranslational regulation of NOS, and/or some non-specific antibody labeling. 相似文献
86.
Dietary purified cis-9,trans-11 conjugated linoleic acid isomer has anticarcinogenic properties in chemically induced mammary tumors in rats 总被引:2,自引:0,他引:2
Lavillonnière F Chajès V Martin JC Sébédio JL Lhuillery C Bougnoux P 《Nutrition and cancer》2003,45(2):190-194
To determine whether the purified 9c,11t conjugated linoleic acid (CLA) isomer, the main dietary isomer, is biologically active on mammary tumor growth, we carried out a dietary intervention study designed to compare its effects with those of a mixture of CLA isomers on the incidence and growth of autochthonous mammary tumors induced by methylnitrosourea in rats. After the initiation step, rats were fed a sunflower oil-based diet (5%) and separated into three experimental groups supplemented with either a 1% homemade synthesized 9c,11t isomer, a 1% CLA isomer mixture, or free fatty acids prepared from sunflower oil for the control group. We found that, in the two CLA groups compared with the control group, CLA levels were about 30 times higher in mammary fat pads and about 10 times higher in tumor tissues. Compared with the control group, there was a 44% and 45% decrease in tumor mass per rat in the CLA mixture and the 9c,11t groups, respectively, at 20 wk of diet (P < 0.05). There was a nonsignificant trend for a decrease multiplicity in CLA groups compared with the control group, with a 30% and 35% decrease in the CLA mixture and the 9c,11t groups, respectively. Incidence and latency were not significantly different between the dietary groups. Although the effect was specifically restricted in reduction in tumor mass, we concluded that the main CLA isomer found in human diet has anticarcinogenic properties in experimental mammary carcinogenesis. 相似文献
87.
88.
Involvement of precerebellar nuclei in multiple system atrophy 总被引:7,自引:0,他引:7
In this semiquantitative study based on 26 post-mortem cases, we describe the involvement of precerebellar nuclei in multiple system atrophy (MSA), a progressive degenerative disorder of the human central nervous system characterized by abnormal, argyrophilic and alpha-synuclein immunopositive intracellular inclusions within selectively vulnerable oligodendrocytes and nerve cells. The Campbell-Switzer silver-pyridine technique with alpha-synuclein immunoreactions using 100-microm thick sections is recommended over more conventional methods, thereby permitting visualization of the pertinent lesions in greater detail and facilitating post-mortem diagnosis of MSA specimens. Affected oligodendrocytes occur in specific fibre tracts and grey matters, with most pathology being observed in projections from the precerebellar nuclei to the cerebellum (ponto-cerebellar, olivo-cerebellar, reticulo-cerebellar tracts) and in descending/ascending fibre tracts of the motor system (cortico-pontine, cortico-bulbar, cortico-spinal, spino-reticular, spino-olivary, spino-cerebellar tracts). Three types of abnormal intraneuronal aggregations occur: (i) a loosely woven network within the cell nucleus; (ii) a latticework accumulating in peripheral portions of the cell body; and (iii) irregularly outlined patches of compact, intensely argyrophilic material usually located within deposits of lipofuscin granules. Counter-staining for the presence of extraneuronal lipofuscin can aid neuropathologists in the recognition of lost existent neurones in MSA. Neurones with inclusion bodies occur in the inferior olivary nuclear complex, lateral reticular nucleus, external cuneate nucleus, conterminal nucleus, interfascicular nucleus, nucleus of Roller, dorsal paramedian reticular nucleus, subventricular nucleus, arcuate nucleus, pontobulbar body and pontine grey. The lateral reticular nucleus and accessory nuclei of the inferior olive sustain the most damage and reveal prominent neuronal loss, followed by the pontobulbar body and arcuate nucleus. The uniformly bilateral damage and, in some cases, even obliteration of the nuclei studied, supply additional evidence for the pathoanatomical substrata of the cerebellar dysfunction that reportedly emerges in the clinical course of MSA. 相似文献
89.
90.
Ethmoid adenocarcinomas: retrospective study of 76 patients 总被引:2,自引:0,他引:2
Stoll D Bébéar JP Truilhé Y Darrouzet V David N 《Revue de laryngologie - otologie - rhinologie》2001,122(1):21-29
From the retrospective study of 76 adenocarcinomas of the ethmoid sinuses, results were expressed in two terms: the morbidity related to surgery and the oncologic outcome. This case study extends between 1975 and 2000. It includes 71 men and 5 women, with an average of 61 years. 81% of them works in wood dust, with a mean duration of exposure of 26 years. The diagnosis of adenocarcinoma is realized in the three months after the first signs, essentially rhinologicals, next neurologicals and ophthalmologicals. The majority of tumors were classified as T3N0M0, i.e. 57.89%. The treatment of this tumors is surgical: 34.2% surgical only and 59.2% with radiotherapy. The transfacial approach (paralateronasal and degloving) and the combined surgery are respectively performed in 36 patients and 35 patients. 23.2% patients had a local recurrence, and 10% developed cervical nodes and systemic metastasis. Survival rate based on the Kaplan-Meier actuarial method is 82% at 3 years, 80% at 5 years, 72% at 10 years. The prognosis of ethmoidal cancer is strictly correlated to local control. Local recurrence is statistically more likely in patients with involvement of the dura, brain and sphenoid sinus. With the analysis of the carcinologics results, we discuss the therapeutics indications of the adenocarcinomas and a new classification. Taking in account the involvement of the dura, sphenoid and orbit. We did not find any statistical differences between T3 patients treated by combined approach (n = 13) or by transfacial approach (n = 15). 相似文献