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61.
目的:建立一种因血管内皮细胞损伤而诱导的大鼠局灶性脑梗死模型。方法:取S—D大鼠11只,分离左侧颈总动脉、颈外动脉和颈内动脉。结扎左颈外动脉远心端,夹闭左翼腭动脉和颈总动脉,经颈外动脉逆行插管并缓慢注入月桂酸钠至颈内动脉系统,造成大脑中动脉血管内皮细胞受损。结果:从模型动物的行为表现、梗死灶形态学和病理学进行考察,10只大鼠均产生一定程度的脑梗死表现,造模成功率为90.9%。结论:该模型的稳定性和重复性较好,能在大脑中动脉的供血区产生恒定的梗死灶,适合进行脑缺血损伤的有关实验研究。 相似文献
62.
The association of diet, obesity, and breast cancer in Hawaii. 总被引:1,自引:0,他引:1
M T Goodman A M Nomura L R Wilkens J Hankin 《Cancer epidemiology, biomarkers & prevention》1992,1(4):269-275
A case-control study of the association of dietary fat and animal protein consumption with breast cancer was conducted between 1975 and 1980 on Oahu, Hawaii. Data from this study were used to explore the relation of selected foods and the interaction of nutrients and foods with other factors, such as body size, age at menopause, and ethnicity on the risk for breast cancer. The sample included 272 postmenopausal breast cancer cases and 296 neighborhood controls. Study participants included Japanese and Caucasian women, aged 45 to 74, who were residents of Oahu. There was a suggestion of a positive-dose response relation (P < 0.01) between sausage consumption and the odds ratio for breast cancer. Significant odds ratios for breast cancer were also found for higher intakes (above the 50th percentile) of diary items, sausage, and all meats combined. The dose-response relation for nutrients and foods tended to be stronger among women with a high Benn's index (kg/cm1.5182) compared to women with a low Benn's index. In general, subjects with high dietary intakes of fat and animal protein who were in the upper 50th percentile of body size were at the greatest risk for breast cancer. However, there was no evidence for an interaction between the dietary variables and body size, ethnic group, age at menarche, age at menopause, or age at first birth that would affect the odds ratio for breast cancer. These data suggest that women with both a high intake of foods rich in fat and animal protein and with a large body size are at increased risk for breast cancer. 相似文献
63.
64.
Otto Robertsson Kaj Knutson Stefan Lewold Stuart Goodman Lars Lidgren 《Acta orthopaedica》1997,68(6):545-553
The Swedish Knee Arthroplasty Register has data on 4, 381 primary operations performed 1985-1995 for rheumatoid arthritis. Of these, 192 were performed with unicompartmental prostheses and 4143 with tricompartmental. 77% were women and the mean age was 66 years. There were 126 first, 20 second, and 1 third revision in tricompartmental arthroplasties, mainly for loosening, infection and patellar problems. There were 38 first, 3 second, and 1 third revision in unicompartmental arthroplasties, mainly for progression of RA and loosening .
Cumulative revision rates (Kaplan-Meier) were calculated. Tricompartmental knees had a 10-year cumulative revision rate of 5% and uni-knees 25%. Patients treated before 1990, men and patients younger than 55 had higher revision rates than patients treated after 1990, women and older patients, respectively. Cemented tibial components resulted in lower revision rates than uncemented ones. There was no significant difference in revision rates between patellar replaced and unreplaced knees or between the 9 commonest implant types. 相似文献
Cumulative revision rates (Kaplan-Meier) were calculated. Tricompartmental knees had a 10-year cumulative revision rate of 5% and uni-knees 25%. Patients treated before 1990, men and patients younger than 55 had higher revision rates than patients treated after 1990, women and older patients, respectively. Cemented tibial components resulted in lower revision rates than uncemented ones. There was no significant difference in revision rates between patellar replaced and unreplaced knees or between the 9 commonest implant types. 相似文献
65.
67.
BACKGROUND. Adenocarcinoma of the small intestine is uncommon. The Hawaii Tumor Registry (HTR) has identified 49 of these tumors since 1960, and the Japan-Hawaii Cancer Study (JHCS) has identified only four of these tumors among a cohort of 8006 Hawaiian-Japanese men followed up for a period of 22 years. Each of the four men reported by the JHCS had multicentric gastrointestinal cancers. METHODS. Newly diagnosed cancers are recorded separately by the HTR and JHCS, and linkage is maintained between the two files. Family histories are available from the JHCS, and these are supplemented by a state population file maintained by the Department of Genetics, University of Hawaii. RESULTS. Five men, all Japanese, were found to have carcinoma of the proximal small intestine. Each had multicentric carcinomas of the gastrointestinal tract. Carcinoma of the stomach and colon was found in the primary relatives of each of four men whose families lived in Hawaii. CONCLUSIONS. The familial clustering of uncommon neoplasms (small bowel carcinoma and multicentric large bowel carcinoma), and the concurrence of gastric and colonic carcinoma suggests that these subjects have a genetic trait that increases susceptibility to a broad range of carcinogens. 相似文献
68.
The wrap around the toe flap from the great toe is considered to be a good reconstructive proce-dure for degloved injuries of the thumb. 1 In this study, we used prefabricated flaps of the medial plan-tar skin to cover a degloved injury of the thumb of a patient unsuitable for application of this method and obtained satisfactory clinical results. 相似文献
69.
特发性甲状旁腺机能减退症颅脑CT及MRI表现 总被引:2,自引:0,他引:2
目的探讨颅脑CT及MRI检查对特发性甲状旁腺机能减退症(IHP)的诊断价值。方法回顾性分析16例经临床确诊的IHP患者头颅CT(16/16)和MRI(3/16)表现,观察病变的范围和密度/信号等特点。结果IHP颅内主要表现为多发钙化性病变,在CT上表现为高密度,CT值114~373HU,在MRT1WI呈稍高信号或高信号,T2WI呈等信号。双侧尾状核、苍白球、壳核及丘脑的对称性、条形或团块状钙化16例;双侧额、颞、顶、枕叶皮层下钙化10例;小脑齿状核钙化6例(双侧4例,单侧2例);侧脑室旁钙化2例。结论CT和MR对IHP的诊断非常重要,其中CT对病变的显示优于MR,与临床结果结合,对IHP具有定性诊断意义。 相似文献
70.
Objective: To study the differences of gene expression between earlier gestational skin and later gestational skin of rats with the aids of single primer amplification (SPA) and high-density oligonucleotide DNA array to understand the molecular mechanism of scarless healing. Methods: Total RNAs were isolated from fetal rat skin of the scarless (E15) and scar-forming (E18) periods of gestation (term =21.5 days). The RNAs from earlier gestational skin (EGS) and later gestational skin (LGS) were both reversely transcribed to cDNAs, then labeled with the incorporation of fluorescent dCTP for preparing the hybridization probes by SPA method. The mixed probes were then hybridized to the oligonucleotide DNA arrays which contained 5 705 probes representing 5 705 rat genes. After highly stringent washing, these DNA arrays were scanned for fluorescent signals to display the differentially expressed genes between the 2 groups of skin. Results: Among 5 705 rat genes, there were 53 genes (0.93%) with differentially expressed levels between EGS and LGS groups, 27 genes, including fibroblast growth factor 2 ( FGF2 ) and follistatin were up-regulated (0.47%) and 26 genes were down-regulated (0.46%) in fetal skin during scarless period versus scar-forming period. Higher expressions of FGF2 and follistatin in EGS than those in LGS were also revealed by RT-PCR method. Conclusions: High-density oligonucleotide DNA array provided a powerful tool for investigating differential gene expression in earlier and later gestational fetal skins. This technology validates that the mechanism of fetal scarless healing is very complicate and the change of many gene expressions is associated with fetal scarless healing. 相似文献