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排序方式: 共有10000条查询结果,搜索用时 125 毫秒
111.
目的:探索上海地区农民人群中α-雌激素受体基因(ER-α)及芳香烃受体基因(Ahr)不同基因形态和老年痴呆症高发风险的可能联系.方法:分别以PCR—RFLP和AS—PCR方法分析一组老年痴呆症患者(n=52)ER-α基因及Ahr基因的多态位点,同一地区的健康人群(n=125)为对照.结果:Alzheimer症病人ER-α基因两个位点突变形态频率显著高于对照人群(Pvu Ⅱ位点:P=0.023,OR=2.94,95%CI 1.13—7.71;Xba I位点:P=0.046,0R=2.28,95% CI 1.003—5.17).Ahr G1721A位点基因型频率在病人组和对照组间无显著差异.结论:ER-α基因多态性可能与Alzheimer症易感性个体差异有关,本工作不支持Ahr基因多态性与老年痴呆症高发风险间的可能关联. 相似文献
112.
MA Ebert J Blight S Price A Haworth C Hamilton D Cornes DJ Joseph 《Journal of Medical Imaging and Radiation Oncology》2004,48(3):347-352
Digital data from 3‐D treatment planning computers is generally used for patient planning and then never considered again. However, such data contains enormous quantities of information regarding patient geometries, tissue outlining, treatment approaches and dose distributions. Were such data accessible from planning systems from multiple manufacturers, there would be substantial opportunities for undertaking quality assurance of radiotherapy clinical trials, prospective assessment of trial outcomes and basic treatment planning research and development. The technicalities of data exchange between planning systems are outlined, and previous attempts at producing systems capable of viewing and/or manipulating imaging and radiotherapy digital data reviewed. Development of a software system for enhancing the quality of Australasian clinical trials is proposed. 相似文献
113.
114.
WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献
115.
J. Bornstein MD D. Zarfati MD N. Goldshmid MD Z. Stolar MA N. Lahat PhD H. Abramovici MD 《American journal of obstetrics and gynecology》1997,177(6):1439-1443
OBJECTIVE: Our purpose was to recognize special features of women with both vestibulitis and constant vulvar pain (vestibulodynia) and to determine whether vestibulodynia is a separate disease entity or a subset of vestibulitis. STUDY DESIGN: Ninety-one women with severe vulvar vestibulitis underwent perineoplasty by a single surgeon during 1992 to 1995. Twenty-five (27%) of them who had vestibulodynia were compared with 66 (73%) who had dyspareunia alone. With univariate and then multivariate analysis, the two groups were compared with regard to demographic, social, and medical variables, the presence of human papillomavirus deoxyribonucleic acid, physical findings in the vestibule, and surgical outcome. RESULTS: The vestibulodynia and vestibulitis groups differed in age (30.5 ± 10.6 years vs 24.7 ± 6.2 years respectively), as well as in marital status (married, 44% vs 18%, respectively), nonuse of contraception (20% vs 1%, respectively), presence of human papillomavirus deoxyribonucleic acid in the vestibule (80% vs 48%, respectively), and failure of surgical treatment (incomplete response rate, 64% vs 2%, respectively). With multivariate analysis, patients with human papillomavirus deoxyribonucleic acid present in the vestibule have an odds ratio of 5.44 (95% confidence interval, 1.45 to 20.33) of belonging to the group with vestibulodynia, whereas dysuria and age have odds ratios of 3.70 (95% confidence interval 1.09 to 12.55) and 1.14 (95% confidence interval 1.04 to 1.24), respectively. CONCLUSIONS: Vestibulodynia is a unique syndrome in that it affects women who are older than those who have vestibulitis alone and it is associated with human papillomavirus deoxyribonucleic acid, dysuria, and a higher surgical failure rate than that for vestibulitis.(Am J Obstet Gynecol 1997;177:43) 相似文献
116.
117.
Impact of education for physicians on patient outcomes 总被引:4,自引:0,他引:4
NM Clark M Gong MA Schork D Evans D Roloff M Hurwitz L Maiman RB Mellins 《Pediatrics》1998,101(5):831-836
118.
目的观察双途径化疗对晚期非小细胞肺癌合并胸腔积液的疗效.方法采用胸腔穿刺、CVP管植入灌注顺铂+地塞米松与长春瑞宾(NVB)+顺铂(DDP)联合静脉化疗相结合的方法治疗33例肺癌.结果治疗胸腔积液的有效率为93.94%,肺部病灶治疗有效率为48.48%.结论双途径给药为临床上值得推广的方法. 相似文献
119.
120.
人血管内皮细胞生长因子基因克隆、表达与纯化 总被引:1,自引:0,他引:1
目的研究人血管内皮细胞生长因子121(hVEGF121)基因在pET-24a(+)中的表达,获得高效表达、具有生物学活性的rhVEGF121。方法提取人原髓白血病细胞(HL60)总RNA,RT-PCR扩增hVEGF121基因,经DNA序列分析后,克隆于高效原核表达载体pET-24a(+),并转化到大肠杆菌B121(DE3)中,经IPTG诱导表达,超滤复性,DEAESephamseFastFlow阴离子交换和SephacryS-100分子筛色谱纯化后,以HUVEC测定其生物学活性。结果SDS-PAGE结果显示,目的蛋白质以包涵体形式存在,表达量达菌体总蛋白质的20%,纯化后rhVEGF121纯度达95%以上,生物学活性检测证实,具有刺激HUVEC增殖的功能。结论在原核系统中实现了hVEGF121的高效表达。 相似文献