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1.
A 1,934-bp muscle-specific promoter from the zebrafish mylz2 gene was isolated and characterized by transgenic analysis. By using a series of 5' promoter deletions linked to the green fluorescent protein (gfp) reporter gene, transient transgenic analysis indicated that the strength of promoter activity appeared to correlate to the number of muscle cis-elements in the promoter and that a minimal -77-bp region was sufficient for a relatively strong promoter activity in muscle cells. Stable transgenic lines were obtained from several mylz2-gfp constructs. GFP expression in the 1,934-bp promoter transgenic lines mimicked well the expression pattern of endogenous mylz2 mRNA in both somitic muscle and nonsomitic muscles, including fin, eye, jaw, and gill muscles. An identical pattern of GFP expression, although at a much lower level, was observed from a transgenic line with a shorter 871-bp promoter. Our observation indicates that there is no distinct cis-element for activation of mylz2 in different skeletal muscles. Furthermore, RNA encoding a dominant negative form of cAMP-dependent protein kinase A was injected into mylz2-gfp transgenic embryos and GFP expression was significantly reduced due to an expanded slow muscle development at the expense of GFP-expressing fast muscle. The mylz2-gfp transgene was also transferred into two zebrafish mutants, spadetail and chordino, and several novel phenotypes in muscle development in these mutants were discovered.  相似文献   
2.
Transiliac bone biopsies were obtained from 55 women treated with teriparatide or placebo for 12-24 months. We report direct evidence that modeling bone formation at quiescent surfaces was present only in teriparatide-treated patients and bone formation at remodeling sites was higher with teriparatide than placebo. INTRODUCTION: Recombinant teriparatide [human PTH(1-34)], a bone formation agent for the treatment of osteoporosis when given once daily subcutaneously, increases biochemical markers of bone turnover and activation frequency in histomorphometry studies. MATERIALS AND METHODS: We studied the mechanisms underlying this bone-forming action of teriparatide at the basic multicellular unit by the appearance of cement lines, a method used to directly classify surfaces as modeling or remodeling osteons, and by the immunolocalization of IGF-I and IGF-II. Transiliac bone biopsies were obtained from 55 postmenopausal women treated with teriparatide 20 or 40 microg or placebo for 12-24 months (median, 19.8 months) in the Fracture Prevention Trial. RESULTS: A dose-dependent relationship was observed in modeling and mixed remodeling/modeling trabecular hemiosteons. Trabecular and endosteal hemiosteon mean wall thicknesses were significantly higher in both teriparatide groups than in placebo. There was a dose-dependent relationship in IGF-II immunoreactive staining at all bone envelopes studied. The greater local IGF-II presence after treatment with teriparatide may play a key role in stimulating bone formation. CONCLUSIONS: Direct evidence is presented that 12-24 months of teriparatide treatment induced modeling bone formation at quiescent surfaces and resulted in greater bone formation at remodeling sites, relative to placebo.  相似文献   
3.
中等专业学校学生重视专业课,而淡化非专业课程,尤其对政治课不感兴趣。兴趣是最好的教师,学生学习兴趣是构成学习动机中最现实、最活跃的成分,对于提高学习效果、智力发展、能力培养及教学质量的全面提高有着巨大的作用。1创设情境,激发学习热情思想政治学科,向学生传授的是马列主义、毛泽东思想、邓小平理论的基本观点、基本方法,以及党和国家在现阶段的路线、方针、政策等。因其理论性较强,故有其严肃性、枯燥性的一面。如若教师没有真挚情感的投入,照本宣科,依葫芦画瓢,则必然出现“听者昏昏然”的局面,学生的学习情绪必然陷于低谷,这种…  相似文献   
4.
血中原卟啉一级标准物质的研制及其应用   总被引:1,自引:0,他引:1  
吴宜群  鲁雁飞 《卫生研究》1994,23(3):129-132
血中原卟啉(EP)是一项评价铅接触人群健康危险度的生物监测指标,也是筛查缺铁性贫血的敏感和特异性指标。为了保证EP测定的准确度,控制分析误差,在分析中应用血EP的标准物质进行质量控制是很有必要的。根据国家计量局颁布的国家一级标准物质技术规范要求,进行了EP冻干血标准物质的研制工作。收集新鲜牛血,加入EP标准,混匀后分装,冷冻干燥,密封后辐射灭菌,低温避光保存。对样品的均匀性及稳定性进行了检验,结果符合国家一级标准物质的规定。并按照国家一级标准物质的要求,组织了9个实验室,使用灵敏、准确的方法进行定值,取得了准确的特性量值。该标准物质经过国内有关实验室试用,通过专家审查鉴定,已被国家技术监督局批准为国家一级标准物质,样品编号为GBW09136、GBW09137。  相似文献   
5.
Zhang  Hui  Che  Lin  Wang  Yanfei  Zhou  Haiyan  Gong  Haihong  Man  Xiaofei  Zhao  Qian 《International urology and nephrology》2021,53(10):2107-2116
Background

Acute kidney injury (AKI) is a common and serious complication of sepsis. MicroRNA-22-3p (miR-22-3p) has been found to be involved in septic AKI progression. The purpose of this study was to analyze both the serum and urinary expression of miR-22-3p in septic AKI patients, and evaluated the clinical value of miR-22-3p in the diagnosis and prognosis of sepsis-induced AKI.

Methods

Serum and urinary expression of miR-22-3p was examined using qRT-PCR. The risk factors related with septic AKI onset were assessed using logistic analysis. A receiver-operating characteristic (ROC) curve was constructed to evaluate the diagnostic performance of miR-22-3p, and the Kaplan–Meier survival curves and Cox regression analysis were used to evaluate the predictive value of miR-22-3p for the 28-day survival of septic AKI patients.

Results

Both serum and urinary miR-22-3p expression was decreased and negatively correlated with kidney injury biomarkers in septic AKI patients. MiR-22-3p expression was a risk factor for AKI onset and had diagnostic accuracy in septic AKI patients. The expression of both serum and urinary miR-22-3p was lower in patients who died, and served as a prognostic biomarker to predict 28-day survival in septic AKI patients.

Conclusion

Serum and urinary miR-22-3p was reduced in sepsis-induced AKI patients, and served as a biomarker to predict AKI occurrence and 28-day survival in sepsis patients.

  相似文献   
6.
The sperm quality of some males is in a critical state, making it hard for clinicians to choose the suitable fertilisation methods. This study aimed to develop an intelligent nomogram for predicting fertilisation rate of infertile males with borderline semen. 160 males underwent in vitro fertilisation (IVF), 58 of whom received rescue ICSI (R-ICSI) due to fertilisation failure (fertilisation rate of IVF ≤30%). A least absolute shrinkage and selection operator (LASSO) regression analysis identified sperm concentration, progressively motile spermatozoa (PMS), seminal plasma anti-Müllerian hormone (spAMH), seminal plasma inhibin (spINHB), serum AMH (serAMH) and serum INHB (serINHB) as significant predictors. The nomogram was plotted by multivariable logistic regression. This nomogram-illustrated model showed good discrimination, calibration and clinical value. The area under the receiver operating characteristic curve (AUC) of the nomogram was 0.762 (p < .001). Calibration curve and Hosmer–Lemeshow test (p = .5261) showed good consistency between the predictions of the nomogram and the actual observations, and decision curve analysis showed that the nomogram was clinically useful. This nomogram may be useful in predicting fertilisation rate, mainly focused on new biomarkers, INHB and AMH. It could assist clinicians and laboratory technicians select appropriate fertilisation methods (IVF or ICSI) for male patients with borderline semen.  相似文献   
7.
蔡蕾  杨钰云  张燕飞  陆建锋  孙菲 《新中医》2023,55(2):107-110
目的:观察口炎清颗粒辅助治疗慢性牙周炎的临床疗效及其对龈沟液炎症因子水平的影响。方法:选择慢性牙周炎患者62例,按随机数字表法分为治疗组和对照组各31例。2组均给予西医常规干预措施,对照组加用罗红霉素胶囊、替硝唑片治疗,治疗组在对照组的基础上联合口炎清颗粒治疗。连续治疗4周后,比较2组临床疗效、牙周炎指标及龈沟液肿瘤坏死因子(TNF)-α和白细胞介素(IL)-1β水平。结果:治疗组总有效率为93.55%,明显高于对照组的70.97%,组间比较,差异有统计学意义(P<0.05)。治疗前,2组菌斑指数、牙龈指数、探针深度、龈沟出血指数评分比较,差异无统计学意义(P>0.05);治疗后,2组上述各项指标均较治疗前明显下降(P<0.05),且治疗组上述指标均低于对照组(P<0.05)。治疗前,2组龈沟液TNF-α、IL-1β水平比较,差异无统计学意义(P>0.05);治疗后,2组TNF-α、IL-1β水平标均较治疗前显著降低(P<0.05),且治疗组TNF-α、IL-1β水平均低于对照组(P<0.05)。结论:西医常规联合口炎清颗粒治疗慢性牙周炎,能有...  相似文献   
8.
9.
目的 探讨上海市≥50岁人群维生素D水平与握力的关系。方法 数据来源于WHO全球老龄化与成人健康研究我国上海市2018-2019年数据,采用logistic回归模型分析维生素D水平与握力的关系,进一步按照性别、年龄及乳制品摄入情况进行分层;采用限制性立方样条曲线绘制维生素D水平与低握力的剂量-反应曲线。结果 共4 391人纳入研究,其中男性2 054人(46.8%);年龄(67.02±8.81)岁;低握力1 421人(32.4%);维生素D不足及缺乏分别为1 533人(34.9%)和401人(9.1%)。在调整相关混杂因素后,logistic回归分析结果显示,维生素D缺乏的人群发生低握力的风险更高(OR=1.41,95%CI:1.09~1.83);在男性中,调整相关混杂因素后,维生素D缺乏与低握力发生风险呈显著正相关(OR=1.67,95%CI:1.12~2.50),而女性中两者之间无关联(OR=1.30,95%CI:0.97~1.74);在60~69岁及≥80岁年龄组中,调整相关混杂因素后,维生素D缺乏与低握力发生风险呈显著正相关(OR=1.57,95%CI:1.05~2.35;OR=2.40,95%CI:1.08~5.31),在乳制品摄入<250 ml/d的人群中,调整相关混杂因素后,二者之间呈显著正相关(OR=1.57,95%CI:1.17~2.09),而在乳制品摄入≥250 ml/d的人群中无明显关联。限制性立方条样图显示,低握力的发生风险可能随维生素D含量的上升而降低,但差异无统计学意义(P>0.05)。结论 维生素D水平与握力存在一定的关系,维生素D缺乏人群出现低握力的风险更高。  相似文献   
10.
报告14 例小儿咽后脓肿,急性型13 例,慢性型1 例;异物性2 例,结核性1 例,邻近炎症扩散引起者2 例,上呼吸道感染所致9 例;14 例颈侧位X线片示脓肿2 例,10 例颈部CT扫描示脓肿7 例。所有病例经脓液引流及抗炎或抗痨治疗后痊愈。  相似文献   
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