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31.
Yang Hee Kim Young In Moon Young Hee Kang Jung Sook Kang 《Nutrition Research And Practice》2007,1(4):298-304
This study was conducted to investigate the hypocholesterolemic effect of simvastatin (30 mg/kg BW) and antioxidant effect of coenzyme Q10 (CoQ10, 15 mg/kg BW) or green tea (5%) on erythrocyte Na leak, platelet aggregation and TBARS production in hypercholesterolemic rats treated with statin. Food efficiency ratio (FER, ADG/ADFI) was decreased in statin group and increased in green tea group, and the difference between these two groups was significant (p<0.05). Plasma total cholesterol was somewhat increased in all groups with statin compared with control. Plasma triglyceride was decreased in statin group and increased in groups of CoQ10 and green tea, and the difference between groups of statin and green tea was significant (p<0.05). Liver total cholesterol was not different between the control and statin group, but was significantly decreased in the group with green tea compared with other groups (p<0.05). Liver triglyceride was decreased in groups of statin and green tea compared with the control, and the difference between groups of the control and green tea was significant (p<0.05). Platelet aggregation of both the initial slope and the maximum was not significantly different, but the group with green tea tended to be higher in initial slope and lower in the maximum. Intracellular Na of group with green tea was significantly higher than the control or statin group (p<0.05). Na leak in intact cells was significantly decreased in the statin group compared with the control (p<0.05). Na leak in AAPH treated cells was also significantly reduced in the statin group compared with groups of the control and CoQ10 (p<0.05). TBARS production in platelet rich plasma was significantly decreased in the groups with CoQ10 and green tea compared with the control and statin groups (p<0.05). TBARS of liver was significantly decreased in the group with green tea compared with the statin group (p<0.05). In the present study, even a high dose of statin did not show a cholesterol lowering effect, therefore depletion of CoQ10 following statin treatment in rats is not clear. More clinical studies are needed for therapeutic use of CoQ10 as an antioxidant in prevention of degenerative diseases independent of statin therapy. 相似文献
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33.
成人成骨细胞与珊瑚羟基磷灰石的体外生物相容性 总被引:13,自引:2,他引:11
目的:研究成人骨髓成骨细胞与珊瑚羟基磷灰石(carolline hydroxyapatite,CHA)在体外培养条件下的生物相容性。方法:抽取健康成人骨髓组织,置于含体积分数为10%胎牛血清的DMEM培养基中培养,传代后改用含地塞米松、β-甘油磷酸钠和维生素C的条件培养基培养,分为CHA复合细胞组和单纯细胞组,不同时间用倒置相关显微镜,HE染色光镜及扫描电镜观察,MTT法进行细胞增殖测定,并进行细胞微量蛋白含量和碱性磷酸酶的定量检测,结果:成人骨髓成骨细胞体外培养时复合或不复合CHA均生长良好,表现出典型成骨细胞的形态特征和生物学特性,CHA利于细胞的贴附,生长与增殖,并对细胞的功能无不良影响,结论:CHA是较理想的骨组织工程支架材料,成骨细胞复合CHA用于骨缺损的修复,具有广阔的临床应用前景。 相似文献
34.
Critical size defect in the canine mandible. 总被引:3,自引:0,他引:3
Jin-Young Huh Byung-Ho Choi Byung-Young Kim Seoung-Ho Lee Shi-Jiang Zhu Jae-Hyung Jung 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(3):296-301
OBJECTIVE: The purpose of this study was to determine the minimum size defect in a canine mandible that would not spontaneously heal during the dog's natural life (the critical size defect). STUDY DESIGN: Sixteen adult female mongrel dogs underwent continuity resection on both sides of the mandible to create bilateral defects. In 8 dogs, mandibular defects ranging from 5 to 20 mm were created with periosteal resection. In the other 8 dogs, mandibular defects ranging from 30 to 60 mm were created preserving the periosteum. The dogs were then killed at 6 months and the defects examined using radiographs and histologic analysis. RESULTS: When the periosteum was removed, mandibular defects greater than 15 mm failed to heal across the entire defect. However, when the periosteum was preserved, mandibular defects needed to be greater than 50 mm in order to fail to heal. CONCLUSION: The critical size defect in a canine mandible model is 15 mm when the periosteum is removed and 50 mm when the periosteum is preserved. 相似文献
35.
神经外科麻醉对体感诱发电位的影响 总被引:1,自引:0,他引:1
目的探讨神经外科手术麻醉对体感诱发电位(SEP)的影响,以期为麻醉和手术处理提供依据。方法随机抽取我科17例全麻手术病人,分成颅内疾病手术组(A组)与脊柱、脊髓疾病手术组(B组),于术前、麻醉(诱导完成)、术始、术中、术毕和术后6个时程连续监测SEP的潜伏期、波幅及波形并记录。结果麻醉后SEP潜伏期延长5.96%,波幅下降24.00%,未出现波形消失的情况。结论麻醉抑制SEP,表现为潜伏期延长和波幅下降,但未出现波形消失的情况。 相似文献
36.
Cheung-Yeoul Park Su-Gwan Kim Myung-Duck Kim Tae-Gwan Eom Jung-Hoon Yoon Sang-Gun Ahn 《Journal of oral and maxillofacial surgery》2005,63(10):1522-1527
OBJECTIVES: Dental lasers have been used for uncovering submerged implants as well as decontaminating implant surfaces when treating peri-implantitis. The objective of this study was to compare the possible alterations of the smooth surface and resorbable blast material (RBM) surface implants after using NdYAG and CO(2) lasers at various energies. MATERIALS AND METHODS: Ten smooth surface implants and 10 RBM surface implants were used. Two smooth surface implants and 2 RBM surface implants served as a control group that was not lased. The remaining implants were treated using NdYAG and CO(2) lasers. The surface of each implant was treated for 10 seconds on the second and third threads. The smooth surface implants (group 1) were treated using a pulsed contact NdYAG laser at power settings of 1, 2, 3.5, and 5 W, which are commonly used for soft tissue surgery; the corresponding energy and frequency were 50 mJ and 20 Hz, 100 mJ and 20 Hz, 350 mJ and 10 Hz, and 250 mJ and 20 Hz, respectively. The group 2 RBM implants were treated using a pulsed contact NdYAG laser. The group 3 smooth surface implants were treated using a pulsed wave non-contact CO(2) laser at 1, 2, 3.5, and 5 W, and the group 4 RBM implants were treated using a pulsed wave non-contact CO(2) laser. Data were analyzed using scanning electron microscopy. RESULTS: The control surface was very regular and smooth. After NdYAG laser treatment, the implant surface showed alterations of all the surfaces. The amount of damage was proportional to the power. A remarkable finding was the similarity of the lased areas on the smooth and RBM surfaces. CO(2) laser at power settings of 1.0 or 2.0 W did not alter the implant surface, regardless of implant type. At settings of 3.5 and 5 W, there was destruction of the micromachined groove and gas formation. CONCLUSION: This study supports that CO(2) laser treatment appears more useful than NdYAG laser treatment and CO(2) laser does not damage titanium implant surface, which should be of value when uncovering submerged implants and treating peri-implantitis. 相似文献
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38.
目的 探讨甲睾酮对雄性小鼠精子的产生及生殖器官的影响.方法 将48只昆明小白鼠随机分为4组,每组12只,每天分别向各组灌胃甲睾酮16 mg/kg,32 mg/kg,64 mg/kg 和等量蒸馏水(对照组),连续10 d.结果 与对照组比较,甲睾酮16 mg/kg组精子活率最高为66.22%(P<0.05);甲睾酮64mg/kg组睾丸指数、精子畸形率、精子密度都极显著和显著地升高(P<0.01和P<0.05),且睾丸组织有较明显的病理学损伤.结论 适量甲睾酮能提高精子活率,大剂量使精子活率降低且畸形率升高. 相似文献
39.
Seunghan Ha Minhee Lee Onseok Lee Gunwoo Lee Jeayoung Kim Jongsub Moon Mingi Kim Chilhwan Oh 《Skin research and technology》2009,15(2):200-213
Background/aims: The objective and quantitative assessment of the skin is important in medical and cosmeceutical research. Assessment of color is an important element for analyzing the surface of the skin, which is usually determined subjectively by a doctor or using color analysis devices. These devices, however, cannot provide correct color information because color is construed from the mean value of the observation region, and analysis of color distribution is impossible. The purpose of this paper is to develop an objective analysis method to permit skin color measurement of each pixel unit of an image and analyze the distribution of skin surface color. Methods: The Skin Color Distribution Analyzer (SCDA) is an analysis method newly developed at the Research Institute for Skin Image at Korea University. The SCDA system presented in this paper performed a novel form of quantitative and objective analysis of skin color distribution using each pixel color model parameter found in image wavelength information. In this paper, distribution analysis was conducted on normal skin and skin lesions and skin affected by artificially induced irritant contact dermatitis and pigmented nevous. The method selected a grade using a color model parameter. Twenty healthy Korean males participated in this study. A comparative study of the eight anatomical areas was performed, including the exposure and non‐exposure parts and the medial aspect and the lateral aspect of the forearm. A reliability test for the SCDA system was also conducted with a spectrometer (SPEC) using the color analysis method. Results: Each skin lesion was precisely segmented by grade and each parameter hada different statistical significance for results of analysis of distribution in pigmented nevous and the artificially induced irritant contact dermatitis. Parameters L*, b*, a*, and EI showed salient traits. Showed resemble measured result in the SCDA system and the SPEC of normal skin. The exposed site, in comparison with the non‐exposed site, showed a notable difference in the L* parameter and a significant statistical difference in the x and z parameters, except b*. The comparison of the medial and lateral aspects of the forearm showed a notable difference in the L* parameter and a significant statistical difference in the parameters except y and b*. In the reliability test result using the SCDA system and the SPEC, the SCDA system was highly reliabile in terms of the CV value in all color model parameters. Conclusions: The color distribution analysis method using the SCDA system has revealed an aspect that the existent method of medical research has not shown, and is considered to be more reliable than other methods. This method can provide better study findings because it can be applied to other fields in addition to the medical science field and the ripple effect is thought to be bigger in other science field too. 相似文献
40.