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71.
OBJECTIVE: To understand the role of nasal mucous epithelial cells to hypoxia in early stage of nasal polyps(NP) formation. METHODS: Epithelial cells of NP and inferior turbinate (IT) were cultured without serum under normal oxygen and hypoxia, and stimulus of inflammatory cytokines. Erythropoietin (EPO) was regarded as hypoxia mark, and expression of vascular endothelial growth factor(VEGF) mRNA and protein derived from epithelial cells were detected respectively by in situ hybridization and ELISA. RESULTS: 1. Under hypoxia, EPO mRNA was expressed intensely in epithelial cells from NP and IT, and there was no significant difference between both of them. This result suggested that EPO might be regarded as a hypoxic mark. 2. The ability of producing VEGF mRNA increased with cytokines stimulation, especially under hypoxia. Protein level of VEGF from epithelial cells of NP and IT increased with cytokines stimulation, especially in hypoxia and was time-dependent. CONCLUSION: Epithelial cells actively produce vast VEGF under hypoxia. The VEGF induced by hypoxia of the mucosa in middle meatus is of importance in the formation of nasal polyps(NP) in early stage, which may be the major cause of NP formation in middle meatus. 相似文献
72.
Computed tomographic (CT) scans of the brain in a child with Smith-Lemli-Opitz syndrome revealed enlargement of the ventricular system, hypoplasia of the cerebellum, and abnormal thickening of the gray matter, consistent with pachygyria. These findings have been previously noted in autopsies performed on patients with this disorder. We conclude that CT scanning is a valuable tool in the evaluation of children suspected of having the Smith-Lemli-Opitz syndrome. 相似文献
73.
Normal seminal vesicles were studied histologically in 80, and by Feulgen’s cytophotometric method in 10 autopsied cases (males,
44–82 years of age). In every case large, hyperchromatic nuclei were found. By cytophotometry euploid polyploid atypia was
also shown in every case, which is characteristic of benign hormonal dysplasia. 相似文献
74.
来源于骨髓和脐带血的基质细胞基本特性的比较 总被引:5,自引:0,他引:5
目的比较骨髓与脐带血细胞体外培养基质细胞的基本特性,为基质细胞的选择应用提供依据.方法用Dexter长期培养体系培养骨髓和脐带血基质细胞,以细胞增殖、细胞形态、细胞化学染色、细胞表面及基质细胞支持另一骨髓细胞形成的鹅卵石造血区(CAFC),长期培养起始细胞(LTC-IC)为指标,比较两者的生长特性、成分及功能.结果①细胞生长特性:出现贴壁细胞时间,骨髓细胞为培养3d,脐带血细胞为培养5~6d;细胞融合成片时间,骨髓细胞为培养10~14d,脐带血细胞为培养12~18d;第21天细胞增殖数,骨髓比脐带血细胞增殖少;②细胞成分:21d培养后细胞成分,骨髓来源者以成纤维细胞为主,其次是巨噬细胞与内皮细胞,脂肪细胞最少;脐带血细胞来源者,以巨噬细胞为主,其次是内皮细胞、成纤维细胞,偶见脂肪细胞;细胞化学与上述结果基本一致;细胞表面抗原检测,CD14、CD45的表达骨髓细胞明显低于脐带血细胞;③细胞功能:骨髓来源的基质细胞较脐带血细胞的基质细胞支持另一骨髓细胞形成的CAFC和LTC-IC明显多.结论①生长特征:形成贴壁细胞时间骨髓较脐带血短,骨髓细胞比脐带血细胞有核细胞数增殖快、持续时间相对短;②细胞成分特性:骨髓来源形成的基质细胞以成纤维细胞为主,脐带血来源者以巨噬细胞为主;③细胞功能特性:骨髓细胞形成的贴壁细胞较脐带血细胞形成的贴壁细胞更利于CAFC、LTC-IC生长. 相似文献
75.
S Amartur Z P Liang F Boada E M Haacke 《Journal of magnetic resonance imaging : JMRI》1991,1(6):721-724
The authors present an improvement to a sigma-filter extrapolation method for the reconstruction of magnetic resonance (MR) images from symmetric discrete Fourier data. By making use of the phase information in the image data, the proposed method can overcome the data inconsistency problem of the original method for handling MR image data with large phase variations, such as those obtained in gradient-echo pulse sequences. Reconstruction results show that its performance is comparable with that of the modified complex sigma-filter method proposed previously to handle the inconsistency problem. However, the new approach has the advantage of reducing computation time by a factor of two with use of a sigma filter applied to real instead of complex images. It is expected that this method will be more practical for use in clinical MR imaging systems. 相似文献
76.
K Mahmood M N Chowdhury E A Ayoola I A Mofleh R S Rashed F Z Faleh 《Tropical gastroenterology》1991,12(4):188-191
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture. 相似文献
77.
Rats exposed on their first postnatal day to 100% nitrogen for 25 min developed hyperactivity and lower performance in passive avoidance task during development. Administration of MK-801 (0.5 mg/kg i.p.) 1 h before anoxia or (0.25 and 0.5 mg/kg) 1 h after completely reversed this behavioral impairment. Senescent rats (24-26 months) exposed to hypoxia (92% N2 + 8% O2) for 5 h failed in their performance in C.A.R., 30 days later. Pretreatment with MK-801 (1 mg/kg i.p.) completely reversed this impairment. These data suggest that activation of endogenous NMDA receptors produces different behavioral consequences in neonatal and senescent rats and that MK-801 administration close to exposure of animals to anoxia or hypoxia can prevent such damage, thus preventing behavioral impairments in postnatal as well as in senescent rats. 相似文献
78.
Z M Huang D Thewke Q Q Gong D Schlichter W D Wicks 《Brain research. Molecular brain research》1991,11(3-4):309-319
Transient transfection of pLB2CAT constructs bearing short synthetic oligonucleotides derived either from the tyrosine hydroxylase (TH) promoter or other sources was used to examine functional cAMP regulatory element (CRE) activity in a variety of cell lines. The region containing only the putative TH CRE was found to be as or more effective in conferring cAMP responsiveness onto pLB2CAT (which employs the TK promoter) than the immediate 272 bp region of the TH promoter. Increases in CAT activity of 10- to 20-fold were observed in JEG-3 cells with a single insert of the TH CRE region (-31 to -54) in pLB2CAT, and the presence of a second insert generated only a modest further increase. This construct also responded to cAMP in 4 other cell lines tested but the degree of increase was less dramatic. Inserts containing the consensus 8 bp CRE motif embedded in other natural or artificial contexts served generally as weak functional CREs in all cell lines tested. In vitro analysis revealed that a specific protein-DNA complex apparently containing a single protein with a MW of 45-50 kDa was formed equally well with JEG-3 cell nuclear extract and CRE-bearing-TH and other fragments which produced dramatically different cAMP effects in vivo. These results suggest specificity in the effects of cAMP on different CREs which are dictated by contextual differences. 相似文献
79.
Oncologic screenings of the populations in the areas with increased incidence of esophageal cancer have revealed Barrett's ulcer in 1 percent of the examinees. Endoscopic and cytologic characteristics of this condition are presented. Precancer changes--severe dysplasia--are most frequent in male Kazakhs (14.1 percent) aged 50 to 59 (14.7 percent). Subjects with Barrett's ulcer developing severe dysplasia, as evidenced by cytograms, should be included in the group of subjects at risk for carcinoma of the lower third of the esophagus and cardia. 相似文献
80.
本文用磷酸盐Giemsa法观察了小剂量X射线照射对人离体外周血淋巴细胞SCE的影响。其结果照射组各剂量点均不明显地高于对照组,证实了SCE对电离辐射不敏感,说明染色体结构畸变和SCE的发生是彼此独立的两个不同事件。 相似文献