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631.
微核实验评价自制烤瓷合金的生物相容性 总被引:1,自引:1,他引:1
目的:通过微核实验检测自制Ni-Cr-Ti烤瓷合金对小鼠的致畸作用,评价其生物相容性.
方法:实验于2006-04/08在中国医科大学中心实验室完成.①实验分组:选择N1H纯系小鼠80只,按随机数字表法分为8组,每组10只:Ni-Cr-Ti合金组(剂量分别为0.02,0.002,0.000 2 mL/kg)、纯钛浸提液组(剂量分别为0.02,0.002,0.000 2 mL/kg),阴性对照组(生理盐水),阳性对照组(注射用环磷酰胺,75 mg/kg).②实验方法:按50 mL/kg口服同剂量的浸提液,各组均于一次给药后24 h,麻醉后处死小鼠,取小鼠骨髓细胞.③实验评估:光镜下计数1 000个嗜多染红细胞的微核细胞数,并计数嗜多染红细胞与正红细胞的比值,即P/N比值.比值≥1,属于正常,比值<1,则可能受试物对骨髓细胞产生毒性.
结果:Ni-Cr-Ti合金组、纯钛浸提液组每1 000个嗜多染红细胞的微核细胞数与阴性对照组比较,差异无显著性意义(P>0.05),即Ni-Cr-Ti合金、纯钛浸提液对骨髓细胞无毒性.阳性对照组每1 000个嗜多染红细胞的微核细胞数高于Ni-Cr-Ti合金组、纯钛浸提液组,差异有显著性意义(P<0.01),对骨髓有毒性作用.Ni-Cr-Ti合金组、纯钛浸提液组P/N比值均≥1.
结论:自制Ni-Cr-Ti合金对小鼠无致畸作用,有较良好的生物相容性. 相似文献
632.
Published reports have confirmed the superior sensitivity of the manual hexadimethrine bromide (Polybrene) test (MPT) for demonstrating many alloantibodies in vitro; however, the clinical significance of alloantibodies demonstrable exclusively by MPT has not been shown conclusively. A patient with macroglobulinemia experienced chills, fever, hemoglobinemia, and hemoglobinuria following the transfusion of 1 unit of red cells (RBCs) shown to be compatible by the low-ionic-strength antiglobulin (LIS-AG) method. Serologic investigation was negative. Intravascular hemolysis occurred with a second "compatible" unit. Serologic studies were again negative by LIS-AG and ficin-AG methods, but revealed anti-Jka by MPT. Both donors were Jk(a+b-), and 51Cr studies of the second donor's RBCs revealed a t1/2 of less than 30 minutes, with marked intravascular hemolysis. A LIS-AG-compatible Jk(a-) unit was transfused uneventfully, but with no rise in hematocrit. MPT next revealed anti-C; subsequent 51Cr studies with the Jk(a-), Cc donor's RBCs showed a 51Cr t1/2 of 100 minutes with slight intravascular lysis. Four transfusions of Jk(a-), C- blood were uneventful, but 5 days later the patient's hemoglobin declined. The following day, anti-E was demonstrable exclusively by MPT. 51Cr-labeled Jk(a-), C-, E- RBCs had normal 24-hour survival. The patient's hemoglobin rose to 11 g per dl following transfusions of Jk(a-), C-, E- RBCs, and he was discharged. In vitro studies employing the patient's purified IgM paraprotein revealed no interference with alloantibody binding or detection. 相似文献
633.
OBJECTIVES: We evaluated mortality from cardiovascular disease (CVD), coronary heart disease (CHD) and all causes in relation to use of any hormone therapy (HT) and HT with oestradiol and norethisterone or levonorgestrel. DESIGN: Population-based cohort study. SETTING AND SUBJECTS: Women in three Norwegian counties were invited to a health survey in 1985-88 and 82.8% participated. In all 14 324 post- or perimenopausal women aged 35-62 years, including 702 HT users with a mean age of 48.8 years, were followed for 14 years. RESULTS: Women using HT had mortality from all causes and CVD comparable with that of nonusers. The relative risk (RRs) for CVD mortality amongst all women were 0.69 (95% CI: 0.35-1.33) for users of HT, and 0.96 (95% CI: 0.43-2.17) for users of HT with norethisterone or levonorgestrel. Amongst women free of self-reported cardiovascular health problems at baseline all-cause, CVD and CHD mortality tended to be lower amongst users of HT whilst HT use was linked with increased mortality amongst women with cardiovascular health problems. CONCLUSIONS: In this cohort of women around the usual age of menopause all-cause or CVD mortality amongst users of HT, most often oestradiol combined with norethisterone or levonorgestrel, was not markedly different from that of nonusers. Early CHD events amongst HT users prior to the baseline survey, together with selective inclusion of healthy subjects, may in part explain protective effects of HT on CHD reported from previous observational studies. 相似文献
634.
Coffee and incidence of diabetes in Swedish women: a prospective 18-year follow-up study 总被引:7,自引:0,他引:7
Rosengren A Dotevall A Wilhelmsen L Thelle D Johansson S 《Journal of internal medicine》2004,255(1):89-95
Abstract. Rosengren A, Dotevall A, Wilhelmsen L, Thelle D, Johansson S (Sahlgrenska University Hospital/Östra, Göteborg; Göteborg University, Göteborg; AstraZeneca Research and Development, Mölndal; Sweden). Coffee and incidence of diabetes in Swedish women: a prospective 18‐year follow‐up study. J Intern Med 2004; 255: 89–95. Objectives. To examine the long‐term incidence of diabetes in relation to coffee consumption in Swedish women. Design. Prospective longitudinal cohort study. Setting. City of Göteborg, Sweden. Subjects. A random population sample of 1361 women, aged 39–65 years, without prior diabetes or cardiovascular disease took part in a screening study in 1979–1981 with questionnaires, physical examination and blood sampling. Main outcome measures. The development of diabetes until 1999 was identified by questionnaires in a second screening and the Swedish hospital discharge register. Results. Altogether, there were 74 new cases of diabetes. The risk of developing diabetes was 475 per 100 000 person‐years in women who consumed two cups of coffee or less per day, 271 in women who consumed three to four cups per day, 202 with a consumption of five to six cups per day, and 267 in drinkers of seven cups or more per day. Associated hazard ratios, after adjustment for age, smoking, low physical activity, education and body mass index were 0.55 (0.32–0.95), 0.39 (0.20–0.77) and 0.48 (0.22–1.06) for daily consumption of three to four, five to six and seven cups or more, respectively, with a consumption of less than two per day as reference. Additional adjustment for serum cholesterol and triglycerides attenuated the relation between coffee and diabetes slightly, indicating a possible mediating effect on the effect of coffee by serum lipids. Conclusions. The findings of the present study support the hypothesis that coffee consumption protects from the development of diabetes in women. 相似文献
635.
Jodhbir S Mehta FRCOphth Leonard H Yuen MRCOphth MPH Lakhbir S Mengher DPhil MRCOphth Miltos Papathanassiou MD Bruce DS Allan MD FRCOphth 《Clinical & experimental ophthalmology》2010,38(8):764-767
Background: We evaluate the Visian Implantable Collamer Lens (Staar, Monrovia, CA, USA) phakic intraocular lens for treating post‐keratoplasty anisometropia. Methods: Case series of three eyes (2 phakic and 1 pseudophakic). Results: The mean age was 47.3 years (range 30–73 years), with a minimum of 3‐month follow up. The mean preoperative spherical equivalent was ?8.75 ± 5.17 D (?4.00 to ?14.25 D) improving to ?0.29 ± 1.21 D postoperatively (range 0.75 to ?1.625 D). Mean logMAR uncorrected visual acuity improved from 1.66 ± 0.60 (6/240) preoperatively to 0.41 ± 0.52 (6/152). Mean logMAR best spectacle‐corrected visual acuity improved from 0.32 ± 0.15 (6/12) preoperatively to 0.10 ± 0.11 (6/7.5). Anisometropia improved from a difference of 6.37 ± 2.59 D preoperatively to 2.09 ± 1.37 D postoperatively, and there were no complications. Conclusion: Our technique for this clinical indication shows that the Visian Implantable Collamer Lens is a safe and effective alternative for treating post‐keratoplasty anisometropia. 相似文献
636.
Kirsten Mehlig Elisabeth Strandhagen Per-Arne Svensson Annika Rosengren Kjell Torén Dag S. Thelle Lauren Lissner 《Alcohol》2014
Alcohol consumption at moderate levels has been associated with decreased risk of coronary heart disease (CHD). However, the cardio-protective effect of alcohol may be restricted to subjects with a particular genotype of the cholesteryl ester transfer protein (CETP) polymorphism. There is evidence for this from one study in men, but the finding has not been confirmed since. The present study specifically re-examines the potential modification of the association between alcohol consumption and CHD by the CETP TaqIB (rs708272) polymorphism in a sample including both men and women. The INTERGENE case-control study consists of 618 patients with CHD and 2921 control subjects, of whom 19% were homozygous for the CETP TaqIB B2 allele. Alcohol consumption was categorized into sex-specific tertiles of ethanol intake, with non-drinkers constituting a separate category. Logistic regression was used to determine the association between CHD with genotype, ethanol intake, and their interaction. Participants with intermediate ethanol intake (2nd tertile) had lower risk of CHD than those with low ethanol intake (odds ratio [OR] = 0.65; 95% confidence interval [CI] 0.50–0.85). The strongest protective association was seen in the CETP TaqIB B2 homozygotes for intermediate vs. low ethanol intake (odds ratio OR = 0.21; 95% CI 0.10–0.44). The interaction between ethanol intake and genotype was statistically significant (p = 0.008), and of similar size in men and women though significant only in men (p = 0.01). The effect modification could not be explained by differences in lifestyle, socioeconomics, or alcohol-related biological variables such as HDL–cholesterol. Our study is the first to replicate previous findings of an effect modification in men. It gives only suggestive results for women, possibly due to the small number of female cases (n = 165). The prevented fraction for the favorable combination of genotype and alcohol consumption is about 6%, a value suggesting that the cardio-protective effect of moderate alcohol consumption applies only to a small segment of the general population. 相似文献
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