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91.
Qian KX Zeng P Ru WM Yuan HY Feng ZG Li L 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(3):290-292
Our former work demonstrated that our impeller pump could support the circulation of experimental animals for several months without harm to blood elements or organ function. The termination of the experiments was mostly related to wear of the mechanical bearing and thrombosis along the bearing. To solve the bearing problem, we investigated a magnetic bearing in our lab, which resulted in some new problems, such as complicated design and control, considerable energy consumption, and lesser reliability. Progress in developing an impeller pump for long-term application has recently been achieved. Instead of using a sliding bearing system, we devised a rolling bearing system. Its service life is more than 10 years because of a wearproof roller made of ultra high molecular weight polythene. To avoid thrombus formation, we introduced a special purge system to the bearing, allowing the saline with heparin to be infused through the bearing into the pump. The bearing, therefore, keeps working in the saline, and no thrombus will be formed. Animal experiments demonstrated that a 30 ml fluid infusion per hour is enough to prevent thrombus formation. With these improvements, the impeller pump has continuously run for 8 months, and no bearing wear can be measured. The device, weighing 150 g, is fully implantable, consumes approximately 9.6 watts, and delivers a 9L/min blood flow against a 120 mm Hg mean pressure and reaches a highest total efficiency of 24.7% for the motor (including the controller) and pump. The system can produce both pulsatile and nonpulsatile flow according to requirements. 相似文献
92.
93.
A patient with Waardenburg syndrome type II associated with Hirschsprung megacolon and Marcus Gunn ptosis is presented. It is suggested that these different anomalies are manifestations of the same neurocrestopathy. 相似文献
94.
Jocelyne Fleury-Feith Laurence Kheuang Lin Zeng Jean Bignon Christian Boutin Isabelle Monnet Marie-Claude Jaurand 《The Journal of pathology》1995,177(2):209-215
The aim of this study was to determine, by transmission electron microscopy, the differentiation features of 21 human malignant mesothelioma cell lines (HMCLs) established from 13 specimens of 12 confirmed human malignant mesotheliomas, and of tumours induced in nude mice injected with 16 HMCLs. Fifty per cent of HMCLs showed typical mesothelial differentiation (long and slender microvilli, desmosomes, perinuclear intermediate filaments); 29 per cent did not show differentiation; and the remainder were poorly differentiated. Three human tumour specimens gave several different HMCLs; the cell lines obtained from a given tumour exhibited variable mesothelial differentiation. Eleven HMCLs were compared with the native tumour. Four were similar to the tumour and seven were less well differentiated, in most cases in relation to their microvilli. With six HMCLs, tumours induced in nude mice were less well differentiated than the corresponding cell lines, whereas with four HMCLs, tumours were equally or better differentiated. However, in most nude mice tumours, typical mesothelial microvilli were present. These results show that cell lines established from malignant mesothelioma may exhibit dedifferentiated features. However, while the variability in ultrastructural differentiation may result from the culture microenvironment, it could also be related to the state of differentiation, of the native tumour sample and to tumour cell heterogeneity. 相似文献
95.
Correlation of AIB1 overexpression with advanced clinical stage of human colorectal carcinoma 总被引:7,自引:0,他引:7
AIB1, a member of the steroid receptor coactivator 1 family, has been cloned on 20q12 and is a candidate oncogene in human breast cancer. It is commonly amplified and overexpressed in several types of human cancers. In this study, we examined the expression of AIB1, as related to clinicopathologic features, in 85 human colorectal cancers (CRCs). The status of the number of AIB1 copies, p53 expression, and DNA ploidy was also analyzed. The overexpression of AIB1 was detected in 35% of CRCs. Amplification of AIB1 was observed in 10% of CRCs. In addition, the overexpression of AIB1 was observed more frequently in CRCs in later clinical stages (T3 N1 M0/T3 N0 2M1), compared with that in T3 N0 M0 stage (P < .05). These results suggest that overexpression of AIB1 might provide a selective advantage for the developmental growth and/or progression of subsets of CRCs. In addition, a significant correlation (P < .05) of overexpression of AIB1 with p53 overexpression as well as with aneuploid DNA content was observed in these CRCs. The overexpression of p53 was also correlated significantly with CRC DNA ploidy (P < .05). Furthermore, there was a substantial population of CRCs showing overexpression of both AIB1 and p53 protein and all had aneuploid DNA content; most of these were in the later clinical stage. These findings suggest a possible convergence of AIB1 with a pathway involving p53, which might induce chromosomal instability and affect the clinical phenotype of a subset of CRCs. 相似文献
96.
Descamps D Flandre P Joly V Meiffrédy V Peytavin G Izopet J Tamalet C Zeng AF Harel M Lastère S Aboulker JP Yéni P Brun-Vézinet F;NOVAVIR 《Journal of acquired immune deficiency syndromes (1999)》2002,31(5):464-471
The authors studied the effect of zidovudine (ZDV) resistance mutation on virologic response to treatment with ZDV or stavudine (d4T) each in combination with lamivudine and indinavir. Viral genotyping was performed on plasma HIV-1 RNA at study entry and concerned 155 patients previously treated with ZDV, didanosine, or zalcitabine and enrolled in the NOVAVIR (Agence National de Recherche sur le SIDA [ANRS] 073) trial. Three virologic responses were investigated: early response (<50 copies/mL at week 24), late response (<500 copies/mL at week 80), and virologic failure (two HIV-1 RNA >5000 copies/mL). Patients were classified as resistant or susceptible to ZDV according to the ANRS algorithm. Plasma viral RNA from 123 of 155 patients had two or more ZDV resistance mutations. The number of ZDV resistance mutations was positively correlated with the duration of prior antiviral therapy (p <.001). At week 24, 74% and 77% of patients with virus classified as resistant were responders in the d4T and ZDV arm, respectively. Similar results were found at week 80. Virologic failure was reached in 7 of 24 patients with virus classified as susceptible and in 26 of 131 patients with resistant virus (p =.29). In the ZDV arm, patients classified as resistant had longer times to virologic failure than those classified as susceptible (p =.003). In conclusion, sustained virologic response despite presence of ZDV resistance mutations implies that these mutations do not preclude an early and durable response to treatment with a potent three-drug regimen in these patients. Patients susceptible to ZDV had lower median mean corpuscular volumes and lower random indinavir levels, suggesting that adherence was the main reason for failure. 相似文献
97.
Recurrent genetic alterations in 26 colorectal carcinomas and 21 adenomas from Chinese patients 总被引:5,自引:0,他引:5
He QJ Zeng WF Sham JS Xie D Yang XW Lin HL Zhan WH Lin F Zeng SD Nie D Ma LF Li CJ Lu S Guan XY 《Cancer Genetics and Cytogenetics》2003,144(2):112-118
Colorectal cancer (CRC) is one of the most common malignancies worldwide. The incidence of CRC in the Chinese population has increased dramatically during the last two decades; however, nonrandom chromosomal alterations in Chinese patients have not been described. In the present study, comparative genomic hybridization (CGH) was applied to detect recurrent chromosome alterations in 26 primary colorectal carcinomas and 21 colorectal adenomas from Chinese patients. In CRC, several recurrent chromosomal changes were found, including gains of 8q (14/26 cases, 54%), 20q (54%), 3q (50%), 13q (50%), 5p (46%), 7p (42%), 7q (42%), and 12p (38%) and losses of 18q (65%) and 17p (42%). From comparison with previous CGH studies, the frequent gains of 3q and 12p might be distinctive occurrences in Chinese patients. The distribution of frequently found chromosomal alterations in different locations was studied. The gain of 20q was more frequently found in colon cancer (P<0.01) and the gain of 12p was more frequently found in rectal cancer. Chromosomal alterations were found in 19/21 of adenomas; the most frequent chromosomal alteration was the loss of 18q (9/21 cases, 43%). These recurrent alterations provide several starting points for the isolation of candidate oncogenes and tumor suppressor genes. 相似文献
98.
构建7q32区域鼻咽癌和正常鼻咽上皮细胞部分基因的表达图谱 总被引:7,自引:2,他引:7
目的构建7q32区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞的部分基因表达图谱。方法通过差异RT-PCR和Northern杂交的方法检测定位于7q32区域的20个EST在鼻咽癌细胞和鼻咽癌组织及原代培养人正常鼻咽上皮细胞mRNA的表达水平。结果8个EST在鼻咽癌细胞HNE1和原代培养人正常鼻咽上皮细胞中表达量较一致,7个EST在两种细胞中均无表达,3个EST(W72688、H19830、AA130630)在鼻咽癌细胞株中表达上调,而2个EST(AA070437、H90882)在原代培养人鼻咽上皮细胞中表达上调。在13例鼻咽癌活检组织中30.7%(4/13)的AA070437表达下调,77%(10/13)的W72688和77%(10/13)的H19830表达上升。结论构建了7q32区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞部分基因表达图谱,并初步认为A070437的表达下调和W72688、H19830的过表达与鼻咽癌的发生有关。 相似文献
99.
OBJECTIVE: This study aimed to investigate the effects of folate on the monocyte chemoattractant protein-1 (MCP-1) expression and release in rats with hyperhomocystinemia induced by ingestion of excess methionine. METHODS AND RESULTS: Thirty male Sprague-Dawley rats (200+/-20 g) were randomly divided into three groups (n=10 for each group): control group (Control), high-homocystinemia (Hhcy) group, and folate treatment (FA) group. They were fed with a normal regular diet, enriched by 1.7% methionine plus 1.7% methionine and 0.006% folate for 45 days. Our study showed the following: (a) A high methionine diet for 45 days is sufficient to induce hyperhomocystinemia; folate supplementation to the rats fed the high-methionine diet prevented an elevation homocysteine (Hcy) levels in the blood (P<.01). (b) Compared with the Control group, the Hhcy group had elevated plasma levels of MCP-1, and Hcy was significantly correlated with MCP-1 (P<.05). (c) The protein and mRNA expression of MCP-1 in the aorta was higher in rats from the Hhcy group than in rats from the Control group. (d) Most important, after folic acid supplementation, the lowering of Hcy levels was accompanied by a marked reduction of MCP-1 expressed in aortae and released from plasma and peripheral blood mononuclear cells (PBMCs) stimulated by oxidized low-density lipoprotein (P<.05, P<.01). CONCLUSION: Folic acid supplementation not only can blunt the rise in Hcy and reduce MCP-1 released from both plasma and PBMCs of rats with hyperhomocystinemia but also can downgrade MCP-1 expression in the aorta of rats with hyperhomocystinemia. 相似文献
100.
不同年龄人脑视皮质毛细血管密度的计量分析 总被引:1,自引:1,他引:1
本文应用碱性磷酸酶染色,按立体学方法观测了不同年龄(14岁以下儿童4例,成年人2例,60岁以上老人2例)共8例人脑视皮质有纹区各层毛细血管的密度(各层均取40个数据).结果:成年组视皮质第三层血管网3c亚层(位于皮质第Ⅳc层)毛细血管密度平均为1580.79±47.73mm/mm~3;儿童组为1087.19±44.90mm/mm~3;老年组为619.95±21.39mm/mm~3.经方差分析检验,P<0.01,说明在第三层血管网3c亚层三个年龄组之间具有非常显著性差异.讨论了各年龄组之间视皮质有纹区毛细血管密度差异与机能的关系. 相似文献