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991.
应用鼻中隔矫正术和以鼻丘为中心的划痕术治疗鼻中隔偏曲伴变应性鼻炎(PAR)患者32例,术后症状立即消失,术后随访6个月~18个月.仅2例复发,但症状明显较前减轻,鼻中隔矫正术及鼻丘划痕术治疗PAR短期效果满意,是基层医院治疗PAR较理想的手术方法. 相似文献
992.
993.
R J Coates D J Bowen A R Kristal Z Feng A Oberman W D Hall V George C E Lewis M Kestin M Davis M Evans J E Grizzle C K Clifford 《American journal of epidemiology》1999,149(12):1104-1112
This randomized clinical trial examined the feasibility of low-fat dietary interventions among postmenopausal women of diverse backgrounds. During 1992-1994, 2,208 women aged 50-79 years, 28% of whom were black and 16% Hispanic, enrolled at clinics in Atlanta, Georgia, Birmingham, Alabama, and Miami, Florida. Intervention/support groups met periodically with a nutritionist to reduce fat intake to 20% of energy and to make other diet modifications. At 6 months postrandomization, the intervention group reduced fat intake from 39.7% of energy at baseline to 26.4%, a reduction of 13.3% of energy, compared with 2.3% among controls. Saturated fatty acid and cholesterol intakes were reduced, but intakes of fruits and vegetables, but not grain products, increased. Similar effects were observed at 12 and 18 months. Black and non-Hispanic white women had similar levels of reduction in fat, but the decrease in Hispanic women was less. Changes did not vary significantly by education. While bias in self-reported intakes may have resulted in somewhat overestimated changes in fat intake, the reported reduction was similar to the approximately 10% of energy decrease found in most trials and suggests that large changes in fat consumption can be attained in diverse study populations and in many subgroups. 相似文献
994.
S K Reaves J C Fanzo J Y Wu Y R Wang Y W Wu L Zhu K Y Lei 《The Journal of nutrition》1999,129(10):1855-1861
Apolipoprotein B (apoB) exists as two major isoforms and serves as an obligatory component of lipid-rich plasma lipoprotein particles. Apolipoprotein B mRNA editing is a zinc-dependent, site-specific cytidine deamination that determines whether the apoB-100 or apoB-48 isoform is synthesized. The objective of this work was to examine whether dietary zinc levels affect apoB mRNA editing in vivo. Adult male Sprague-Dawley rats were randomly assigned to zinc-deficient (ZD, <0.5 mg Zn/kg diet), zinc-adequate (ZA, 30 mg Zn/kg diet) or zinc-replenished (ZDA, ZD rats fed the ZA diet for last 2 d) dietary groups for 18 d. The ratio of plasma apolipoprotein B-48 (apoB-48) to total apoB was significantly lower in zinc-deficient compared with zinc-adequate rats. Primer extension analysis indicated a modest but significant reduction in hepatic apoB mRNA editing in ZD rats compared with that of the ZA group. In ZDA rats, hepatic apoB mRNA editing and the percentage of plasma apoB-48 to total apoB were not different from ZA rats. The mRNA abundance of hepatic apobec-1 (apoB mRNA editing catalytic subunit 1) was significantly lower in ZD and ZDA rats than in ZA rats. In summary, the plasma ratio of apoB-48 to total apoB protein as well as hepatic apoB mRNA editing and hepatic apobec-1 mRNA levels were reduced in rats consuming a zinc-deficient diet. These data suggest that one or more components of apoB metabolism may be influenced by dietary zinc status. 相似文献
995.
Dietary copper, manganese and iron affect the formation of aberrant crypts in colon of rats administered 3,2'-dimethyl-4-aminobiphenyl 总被引:4,自引:0,他引:4
Aberrant crypt foci (ACF) are preneoplastic lesions for colon cancer. Altered amounts of copper-zinc (CuZnSOD) and manganese (MnSOD) superoxide dismutases have been implicated in multistage carcinogesis of both rodents and humans. Dietary factors are potential modulators of both CuZnSOD and MnSOD activity. The purpose of this study was to investigate the interactive effects of dietary copper, manganese, and iron on 3,2'-dimethyl-4-aminobiphenyl (DMABP)-induced ACF and superoxide dismutase activities in weanling rats fed low or adequate copper (0.8 or 5.1 microg Cu/g diet), low or adequate manganese (0.6 or 17 microg Mn/g diet), and adequate or high iron (37 or 140 microg Fe/g diet). Twelve rats were allowed free access to each of these eight diets for 3.5 wk prior to DMABP administration and for an additional 8 wk after the first DMABP injection. Rats fed low dietary copper had 105% (P < 0.0001) higher formation of DMABP-induced ACF than those fed adequate dietary copper. Rats ingesting low rather than adequate dietary manganese had 23% higher formation of ACF, and rats ingesting high rather than adequate dietary iron had 18% higher formation of ACF. Heart total superoxide dismutase activity was significantly correlated with the number of ACF (r = -0.43, P < 0.0001) in rats administered DMABP. These results suggest that dietary alterations that affect superoxide dismutase activity may affect cancer susceptibility. 相似文献
996.
Preliminary study on HA coating percutaneously implanted in bone 总被引:1,自引:0,他引:1
Yang BC Weng J Li XD Yang ZJ Feng JM Chen JY Zhang XD 《The International journal of artificial organs》1999,22(10):713-718
A comparative investigation on the possibility of hydroxyapatite (HA) coating and pure Ti column to form biological sealing with skin tissue was completed in this study. HA coating and pure Ti column were percutaneously implanted in the tibia of rabbits. Compared with titanium (Ti) implant, HA coating forms epithelial sealing with skin tissue at 6 weeks postoperatively, while the Ti implant may loosen from the implanted site and be lost. The Ti column loosing rate at this time was 50%. However, once the Ti implant becomes fixed with the bone tissue, it can form epithelial sealing with skin tissue just like the HA coating, at 8 weeks postoperatively. At 8 weeks postoperatively, the epithelial sealing is not destroyed in spite of the fact that the HA coating is biodegraded. Our results show that the HA coating can become fixed with the bone faster than the Ti, which is beneficial for epithelial sealing formation. The main role of HA coating for epithelial sealing is beneficial for sealing at the initial period after it is implanted. 相似文献
997.
报告鼻腔鼻窦非上皮源性恶性肿瘤7 例,其中恶性黑色素瘤2 例,恶性神经鞘瘤2 例,非霍奇金氏淋巴瘤2 例,平滑肌肉瘤1 例。因鼻腔鼻窦恶性黑色素瘤罕见,故易误诊,其中1 例因高度疑为此病,经病检证实,及时准确切除了瘤体,术后存活5 年余;恶性神经鞘瘤临床确诊主要依靠病检,诊断平滑肌肉瘤则需结合免疫组化检测,随免疫组化的开展,非霍奇金氏淋巴瘤的临床与病理诊断符合率已有提高,前三者治疗以手术切除为主,非霍奇金氏淋巴瘤则可先化疗再局部放疗。 相似文献
998.
目的 了解保存时间及温度对补体活性的影响。方法:用单向琼脂扩散法和非离心单管法对不同温度和时间下标本的C_3含量及CH50进行测定。结果与结论:血清补体C_5含量在室温下24h、4C下4dC、-10C和-20C下8d内无显著变化;CH50在室温下12h、4C下24h,-10C和-20C下8d内CH50无明显变化。 相似文献
999.
目的:探索诊断早期肝纤维化的敏感指标。方法:用放射免疫法检测236例各型肝病患者血清Ⅲ型胶原(TpyeⅢcolagen,PCⅢ)、Ⅳ型胶原(TpyeⅣcolagen,Ⅳ-C)和板层素(Laminin,LN)水平。结果:各类肝病患者血清PCⅢ、Ⅳ-C和LN水平随病情进展而逐渐升高。以PCⅢ≥135μg/L、Ⅳ-C≥130μg/L为诊断肝纤维化的临界点,其敏感度、特异性、准确率分别达80%以上。结论:表明PCⅢ、Ⅳ-C及LN可作为肝纤维化诊断较为敏感的指标,其中Ⅳ-C对早期肝纤维化的诊断优于PCⅢ及LN,对肝癌的诊断有一定意义 相似文献
1000.
目的:为中国林蛙油和卵渣应用提供科学依据。方法:采用等离子光谱和分光光度计法测定中国林蛙卵油和卵渣中的微量元素。结果:卵油和卵渣中均含 Zn, M n, Cu, Fe 等 9 种人体必需微量元素,且 Zn/ Cu 比值较小。结论:卵油可能具有抗衰老及防治冠心病和高血压等作用。 相似文献