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991.
目的 了解外源性褪黑素对大鼠体温及活动度昼夜节律的影响及其可能的调节机制。方法 正常光照条件下,24h连续记录大鼠的体温及活动度的变化,以不同剂量褪黑素在不同的昼夜时间给药观察体温和活动度节律的变化。结果 大鼠的体温及活动度存在昼夜节律性,给药后昼夜节律性不消失;但体温振幅减小,中值降低。黑暗中期给药后,峰值位相显著延迟;活动度振幅增加,中值显著降低,峰值位相延迟。结论 外源性褪黑素不能使体温或活动度的昼夜节律消失,而只是改变昼夜节律的参数。褪黑素可分别调节体温和活动度的昼夜节律,但对活动度的调节作用更为明显。 相似文献
992.
植物血凝素及淋巴因子激活的杀伤细胞体外抗肿瘤作用的MTT比色法分析 总被引:2,自引:0,他引:2
目的 检测植物血凝素及淋巴因子激活的杀伤细胞(PHA-LAK)的体外广谱抗肿瘤作用。方法 用MTT比色法测定 PHA-LAK对体外培养的K562、MGc80-3、143TK-、HeLa、LoVo等5种肿瘤细胞的杀伤活性。结果PHA-LAK对5种不 同组织器官来源的肿瘤细胞均有明显杀伤活性,在效靶比为7.5:1.0时,PHA-LAK对143TK-细胞的杀伤率可高达 57.3%,杀伤效应随效靶比增加而升高;但在效靶比为15:1时,杀伤效应不随效靶比增加而增高数。结论 (1)来自健康献血 员的PHA-LAK对肿瘤细胞具非特异性杀伤活性,能较好解决传统过继免疫治疗中免疫效应细胞的数量和活性问题; (2)在一定的条件下,MTT法用于检测免疫效应细胞的杀瘤作用时才具灵敏、可靠的优点。 相似文献
993.
本文总结了北京大学口腔医学院3届八年制口腔医学专业学生口腔固定修复学临床前期实习教学的经验,针对实习中出现的典型问题进行了分析,采取了相应的对策和方法,取得了良好的效果. 相似文献
994.
995.
Yu Seong Hyeon Hur Young Hoe Hwang Eu Chang Kim Myung Soo Chung Ho Seok Lee Byung Chan Heo Suk Hee Choi Chan Hwang Jun Eul Bae Woo Kyun Jung Seung Il Kwon Dong Deuk 《International urology and nephrology》2021,53(1):69-75
International Urology and Nephrology - Multidetector computed tomographic urography (MDCTU) is not yet sufficient to be used in the clinical staging of upper tract urothelial carcinoma (UTUC). This... 相似文献
996.
The aim of this study was to assess the relationship between serum folic acid (FA) levels and erectile dysfunction (ED) through a meta-analysis. A research was conducted in MEDLINE via PubMed, Cochrane Library, EMBASE and Web of Science up to 22 November 2020 to identify studies related to FA and ED. Two authors independently screened the literature, evaluated methodological quality and extracted the data. We used RevMan5.3 and STATA 14.0 for meta-analysis. A total of six studies including 1,842 participants were included, and the results showed that the FA levels in the non-ED group were significantly higher than those in the ED group (MD = 3.37, 95% CI 1.49–5.52, p = 0.004). Subgroup analysis indicated that with the increase in ED severity, the difference in FA levels between groups was more obvious (MD: 1.99 vs. 4.63 vs. 5.63). The differences in FA levels between groups seem more significant in the younger group (MD = 4.87, 95% CI 2.58–6.89, p < 0.001) than in the older group (MD = 3.15, 95% CI 2.21–4.08, p < 0.001). In conclusion, FA deficiency is closely related to ED, and the degree of FA deficiency may reflect the severity of ED. In addition, the association seems to be more pronounced in the younger group. 相似文献
997.
Jun Guo Fu Wang Qing Zhou Qiang Geng Qinghe Gao Rui Zhang Chunhe Zhang Zhihua Xuan Jian Cai Bin Bin Qiang Han Boda Guo Bin Yan Jiwei Zhang Elena Colonnello Emmanuele A. Jannini 《Andrologia》2021,53(1):e13915
To evaluate the safety and efficacy of Chinese medicine, Qiaoshao formula combined with dapoxetine was used for the treatment of premature ejaculation in a real-life setting. Nine hundred and five males diagnosed with premature ejaculation were reviewed in this retrospective cohort study. We divided the patients into two groups: dapoxetine alone and Qiaoshao formula combined with dapoxetine according to actual interventions provided to patients in clinics. The perceived intravaginal ejaculation latency time and the premature ejaculation profile measures markedly improved in both groups. However, in men with severe premature ejaculation (baseline perceived intravaginal ejaculation latency time <1 min) and those with baseline age ≤30 years, the perceived intravaginal ejaculation latency time was slightly but significantly longer with combined therapy than with dapoxetine alone (p < .05). Therefore, combined therapy involving the Qiaoshao formula and dapoxetine proved to safe as well as effective for treating premature ejaculation while prolonging the perceived intravaginal ejaculation latency time, which significantly improved the overall satisfaction of the patient and likely that of the couple. 相似文献
998.
Jun Ho Kim Eunsun Oh Young Cheol Yoon Do Kyung Lee Sung-Sahn Lee Joon Ho Wang 《Arthroscopy》2021,37(1):209-221
999.
Zichen Hao Jun Li Bo Li Kareme D Alder Sean V Cahill Alana M Munger Inkyu Lee Hyuk-Kwon Kwon JungHo Back Shuogui Xu Min-Jong Kang Francis Y Lee 《Journal of bone and mineral research》2021,36(1):186-198
Smokers are at a higher risk of delayed union or nonunion after fracture repair. Few specific interventions are available for prevention because the molecular mechanisms that result in these negative sequelae are poorly understood. Murine models that mimic fracture healing in smokers are crucial in further understanding the local cellular and molecular alterations during fracture healing caused by smoking. We exposed three murine strains, C57BL/6J, 129X1/SvJ, and BALB/cJ, to cigarette smoke for 3 months before the induction of a midshaft transverse femoral osteotomy. We evaluated fracture healing 4 weeks after the osteotomy using radiography, micro-computed tomography (μCT), and biomechanical testing. Radiographic analysis demonstrated a significant decrease in the fracture healing capacity of smoking 129X1/SvJ mice. μCT results showed delayed remodeling of fracture calluses in all three strains after cigarette smoke exposure. Biomechanical testing indicated the most significant impairment in the functional properties of 129X1/SvJ in comparison with C57BL/6J and BALB/cJ mice after cigarette smoke exposure. Thus, the 129X1/SvJ strain is most suitable in simulating smoking-induced impaired fracture healing. Furthermore, in smoking 129X1/SvJ murine models, we investigated the molecular and cellular alterations in fracture healing caused by cigarette smoking using histology, flow cytometry, and multiplex cytokine/chemokine analysis. Histological analysis showed impaired chondrogenesis in cigarette smoking. In addition, the important reparative cell populations, including skeletal stem cells and their downstream progenitors, demonstrated decreased expansion after injury as a result of cigarette smoking. Moreover, significantly increased pro-inflammatory mediators and the recruitment of immune cells in fracture hematomas were demonstrated in smoking mice. Collectively, our findings demonstrate the significant cellular and molecular alterations during fracture healing impaired by smoking, including disrupted chondrogenesis, aberrant skeletal stem and progenitor cell activity, and a pronounced initial inflammatory response. © 2020 American Society for Bone and Mineral Research (ASBMR). 相似文献
1000.
Rui Sheng Yuan Wang Yunshu Wu Jun Wang Shiwen Zhang Qiwen Li Danting Zhang Xingying Qi Qingyue Xiao Shuang Jiang Quan Yuan 《Journal of bone and mineral research》2021,36(2):412-423
N6-methyladenosine (m6A), as a eukaryotic mRNA modification catalyzed by methyltransferase METTL3, is involved in various processes of development or diseases via regulating RNA metabolism. However, the effect of METTL3-mediated m6A modification in tooth development has remained elusive. Here we show that METTL3 is prevalently expressed in odontoblasts, dental pulp cells, dental follicle cells, and epithelial cells in Hertwig's epithelial root sheath during tooth root formation. Depletion of METTL3 in human dental pulp cells (hDPCs) impairs proliferation, migration, and odontogenic differentiation. Furthermore, conditional knockout of Mettl3 in Osterix-expressing cells leads to short molar roots and thinner root dentin featured by decreased secretion of pre-dentin matrix and formation of the odontoblast process. Mechanistically, loss of METTL3 cripples the translational efficiency of the key root-forming regulator nuclear factor I-C (NFIC). The odontogenic capacity of METTL3-silenced hDPCs is partially rescued via overexpressing NFIC. Our findings suggest that m6A methyltransferase METTL3 is crucial for tooth root development, uncovering a novel epigenetic mechanism in tooth root formation. © 2020 American Society for Bone and Mineral Research (ASBMR). 相似文献