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81.
82.
乙醇对人绒毛孕酮分泌的影响 总被引:1,自引:0,他引:1
本工作利用灌流技术观察了四种不同浓度的乙醇(0.5%、1%、2.5%、5%)对妊娠早期人工流产新鲜胎盘绒毛分泌孕酮的影响。结果表明,乙醇具有促进孕酮分泌的作用,并存在剂量依赖的关系。提示乙醇可能破坏胎盘激素内分泌的平衡,从而影响胎儿的正常生长与发育。 相似文献
83.
L. J. Burgart J. Zheng Q. Shu J. G. Strickler D. Shibata 《The American journal of pathology》1995,147(4):1105-1111
Likely hot spots for mutations are mitochondrial sequences as there is less repair and more damage by carcinogens compared with nuclear sequences. A somatic 50-bp mitochondrial D-loop deletion was detected in four gastric adenocarcinomas. The deletion included the CSB2 region and was flanked by 9-bp direct repeats. The deletion was more frequent in adenocarcinomas arising from the gastroesophageal junction (4/32, 12.5%) compared with more distal tumors (0/45). Topographical analysis revealed the absence of the deletion from normal tissues except in focal portions of smooth muscle in one case. In two cases, apparent mutant homoplasmy was present throughout two tumors, including their metastases. In the two other cases, the mutation was present in only minor focal portions ( < 5%) of their primary tumors. These findings document the presence of somatic mitochondrial alterations in gastric cancer, which may reflect the environmental and genetic influences operative during tumor progression. 相似文献
84.
Somatic mitochondrial DNA mutations in cortex and substantia nigra in aging and Parkinson's disease 总被引:5,自引:0,他引:5
Simon DK Lin MT Zheng L Liu GJ Ahn CH Kim LM Mauck WM Twu F Beal MF Johns DR 《Neurobiology of aging》2004,25(1):71-81
Oxidative damage to mitochondrial DNA (mtDNA) increases with age in the brain and can induce G:C to T:A and T:A to G:C point mutations. Though rare at any particular site, multiple somatic mtDNA mutations induced by oxidative damage or by other mechanisms may accumulate with age in the brain and thus could play a role in aging and neurodegenerative diseases. However, no prior study has quantified the total burden of mtDNA point mutation subtypes in the brain. Using a highly sensitive cloning and sequencing strategy, we find that the aggregate levels of G:C to T:A and T:A to G:C transversions and of all point mutations increase with age in the frontal cortex (FCtx). In the substantia nigra (SN), the aggregate levels of point mutations in young controls are similar to the levels in the SN or FCtx of elderly subjects. Extrapolation from our data suggests an average of 2.7 (FCtx) to 3.2 (SN) somatic point mutations per mitochondrial genome in elderly subjects. There were no significant differences between Parkinson's disease (PD) patients and age-matched controls in somatic mutation levels. These results indicate that individually rare mtDNA point mutations reach a high aggregate burden in FCtx and SN of elderly subjects. 相似文献
85.
The anatomical relationships between pro-opiomelanocortin-containing axons and serotonin neurons in the nucleus raphe dorsalis (NRD) of the rat were examined at the light microscope level with antibodies against CLIP (corticotropin-like intermediate lobe peptide), alpha-MSH (alpha-melanocyte-stimulating hormone) and serotonin. Sequential double labeling was performed with either immunofluorescence or peroxidase-antiperoxidase techniques. It was observed that the network of POMC-immunoreactive axons displayed a gradient of decreasing density from rostral to caudal levels and from dorsal to ventral parts or the NRD. The examples of close proximity between immunoreactive axons and serotonin cell bodies or dendrites were rather scarce. On the whole, the immunoreactive fibers seemed to run quasi-independently of the serotonin neurons. 相似文献
86.
In this paper, we propose a new approach aimed at handling the temporal Brainstem Auditory Evoked Potentials (BAEPs) non-stationarity. It is pointed out that for some endocochlear pathologies, BAEPs could be randomly delayed from one response to another. This non-stationarity leads to smoothed BAEPs when applying ensemble averaging or any other technique based on BAEPs stationarity. In that case, waves identification is very difficult, sometimes impossible. The problem consists in estimating time delays. Knowing the distribution of delays allows subsequent study of the dynamic of the cochlea and, perhaps, identification of the nature of its pathology. The approach suggested in this paper is based on Simulated Annealing, used to minimize a non-linear criterion involving delays. This technique is advantageously compared to the non-corrected ensemble averaging method, using a set of simulated data based on a realistic model. As an illustration, results based on real signals recorded from two patients are presented and discussed at the end of the paper. 相似文献
87.
目的 研究单克隆抗体CK2 0在恶性上皮性肿瘤和卵巢转移性腺癌组织中的表达及其意义。方法 应用S P法对鼻咽非角化性癌、乳腺浸润性导管癌、肺的鳞癌和腺癌、卵巢黏液性囊腺癌、胃腺癌和结肠直肠腺癌各组总计 6 7例和 4 1例分别进行了CK2 0和CK19检测。结果 CK2 0阳性率 :肺腺癌 1/ 7(14 3% ) ,卵巢浆液性和黏液性腺癌 3/ 12 (33 3% ) ,胃腺癌 3/ 9(33 3% ) ,结肠直肠腺癌组 2 1/ 2 2 (95 5 % ) ,其他癌组织均呈阴性。结肠直肠腺癌组组与其他各组间比较差异有显著性 (P <0 0 1)。CK19在上述 4 1例癌组织中均呈强阳性表达。结论 CK2 0表达对鉴别结肠腺癌和直肠腺癌与肺腺癌和乳腺浸润性导管癌具有高度特异性和较高的敏感性 ;CK2 0高表达对鉴别卵巢原发性腺癌与卵巢的结肠腺癌或直肠腺癌转移具有一定的意义 相似文献
88.
89.
Ikegaya H Iwase H Zheng HY Nakajima M Sakurada K Takatori T Fukayama M Kitamura T Yogo Y 《Journal of virological methods》2005,126(1-2):37-43
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time. 相似文献
90.
应用细胞原位杂交技术,观察经重组小鼠白细胞介素-19(IL-1β)处理后的体外培养的新生1d大鼠中脑黑质神经元c-jun基因的表达.结果显示,培养的黑质细胞多为酪氨酸羟化酶阳性神经元,IL-1β可诱导体外培养的黑质神经元c-junmRNA表达,高水平的表达出现在IL-1β处理后2~4h。说明IL-1β有兴奋黑质神经元的作用,并提示黑质神经元上可能存在IL-1β受体. 相似文献