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91.
目的:观察孕期大鼠摄入不同剂量的氟之后,对子代鼠血液和骨氟浓度及软骨细胞和骨关节结构的影响,以探索通过妊娠期母体给氟预防乳牙龋齿的新途径。方法:给妊娠SD大鼠分别用N aF按1 m g/kg体重、10 m g/kg体重和50 m g/kg体重灌胃至分娩,并用0.9%N aC l灌胃作为对照组。结果:①实验组各组子鼠血清中的氟化物含量均较对照组高(P<0.01);并且与母鼠摄入的氟剂量呈正相关。②在中、高剂量组子鼠上肢骨骨氟的含量明显高于对照组。③在高剂量组子鼠的上肢骨切片中可见软骨细胞和关节结构的破坏。结论:①妊娠期母体摄入的氟化物可进入其子体体内。②当母鼠摄入的氟化物剂量过高时,可引起骨组织的毒性损害。 相似文献
92.
Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献
93.
大蒜素对大鼠心室肌细胞L-型钙通道的影响 总被引:9,自引:0,他引:9
目的:探讨大蒜素对大鼠心室肌细胞L-型钙通道的作用.方法:用急性酶解法获得大鼠的单个心肌细胞,用标准的全细胞膜片钳技术记录钙通道电流.结果:5、50、250和500μmol/L大蒜素分别抑制钙电流4.4%、26.91%、38.06%、72.90%.250μmol/L大蒜素能使心肌细胞钙电流-电压曲线明显上移,峰电流密度从(7.17±0.65)pA/pF减少至(4.44±0.52)pA/pF(n=15,P<0.05),但激活电位、峰电位和翻转电位无明显改变(P>0.05).大蒜素能使钙电流失活曲线明显左移(P<0.05).大蒜素对钙电流激活曲线、失活再复活曲线和频率依赖性无明显影响(P>0.05).结论:大蒜素呈浓度依赖性地抑制心肌细胞L-型钙通道. 相似文献
94.
Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management. It is a common requirement to reuse the data for clinical research. However, we have to face challenges like the inconsistence of terminology in electronic health records (EHR) and the complexities in data quality and data formats in regional healthcare platform. In this paper, we propose methodology and process on constructing large scale cohorts which forms the basis of causality and comparative effectiveness relationship in epidemiology. We firstly constructed a Chinese terminology knowledge graph to deal with the diversity of vocabularies on regional platform. Secondly, we built special disease case repositories (i.e., heart failure repository) that utilize the graph to search the related patients and to normalize the data. Based on the requirements of the clinical research which aimed to explore the effectiveness of taking statin on 180-days readmission in patients with heart failure, we built a large-scale retrospective cohort with 29647 cases of heart failure patients from the heart failure repository. After the propensity score matching, the study group (n=6346) and the control group (n=6346) with parallel clinical characteristics were acquired. Logistic regression analysis showed that taking statins had a negative correlation with 180-days readmission in heart failure patients. This paper presents the workflow and application example of big data mining based on regional EHR data. 相似文献
95.
酸性染料比色法测定乌头属不同药材中乌头生物碱含量 总被引:1,自引:0,他引:1
目的:测定毒性中药附子、川乌、草乌、雪上一枝蒿的乌头生物碱含量,对这4种药材的临床用量进行控制。方法:用酸性染料比色法,测定制附子、川乌、草乌中雪上一枝蒿的乌头生物碱含量。结果:附子中生物碱含量为0.2403 mg/g,川乌为1.0412 mg/g,草乌为2.1149 mg/g,雪上一枝蒿为0.6702 mg/g。结论:本实验中建立的酸性染料比色法测定乌头生物碱含量,可作为评价毒性药材质量的根据。 相似文献
96.
本文将本院需参加住院医师规范化培训非针灸专业硕士研究生60人采用随机数字表法分为2组,每组30人.对照组采取传统方式授课,观察组采取新的教学方法教学.1个月轮转结束后进行考评,采用SPSS17.0对2组学生成绩进行统计学分析,探讨针灸科新教学方案对非针灸专业硕士研究生在针灸科规培中的学习效果.结果,观察组理论成绩、技能成绩、病种诊治率及调查问卷总评分高于对照组(P<0.05).表明针灸科新教学方案的教学效果优于传统教学方法,为针灸学教学在住院医师规范化培训中提供新思路. 相似文献
97.
目前三叉神经的纤维跟踪成像过程中普遍存在人工依赖性问题,主要包括人工绘制感兴趣区域(ROI)及手动筛选目标纤维束,导致结果的不确定性和数据误差。针对此类问题,提出一种数据驱动的三叉神经纤维自动分割算法。利用多组大脑样本的纤维数据,建立数据驱动的纤维聚类图谱,实现新样本纤维数据的自动分割,直接得到三叉神经纤维束。在实验中,选择25组青年健康人的数据作为样本数据。首先,利用FSL软件分割工具提取脑干作为ROI,进行确定性纤维跟踪。其次,通过对20组纤维数据进行多样本配准和谱聚类,创建数据驱动的纤维聚类图谱。根据三叉神经细小的特点,在建立纤维图谱过程中,通过对脑干纤维束进行二次分类来标注三叉神经纤维束。最后,选择5组青年健康人的新样本数据,将其脑干纤维数据应用纤维图谱自动分割得到三叉神经纤维束,并计算同一样本数据的自动分割结果与手动分割结果之间的加权Dice系数。结果显示,所提出的方法成功分割5组数据的三叉神经纤维束,而传统人工方法成功识别4组三叉神经纤维束,两者结果之间的加权Dice系数分别为0.865,0.939,0.824,0.942。该方法可以有效避免人为因素的影响,提高神经外科医生... 相似文献
98.
Xiuyu Zhu Hao Qian Hongxiao Wu Quan Zhou Huiping Feng Qiang Zeng Ye Tian Shengqian Ruan Yajun Zhang Shikun Chen Dongming Yan 《Materials》2022,15(17)
The geopolymerization of aluminosilicate materials in alkaline environments is a complex physicochemical process that greatly influences the microstructure and engineering performances. This work aims to reveal the geopolymerization process of metakaolin-based geopolymer (MKG) in the first 5 d. Physicochemical characteristics of different evolution stages are disposed of in chronological order. The evolutions of electrical resistivity, dehydration process, volume deformation, and ionic concentration are comprehensively analyzed. Results show that chemical dissolution produces large dismantled fragments rather than small free monomers. The formation of a solid matrix follows the “spatial filling rule”, which means that gels grow by locking swelling fragments to form a framework, then densely filling residual space. Based on chemical models, early geopolymerization of MKG can be divided into six stages from the physicochemical perspective as dismantling, locking fixation, free filling, limited filling, second dissolution, and local mending. Those findings expand the understanding of the phase evolution of the early geopolymerization process; thus, the microstructure of MKG can be better manipulated, and its engineering performances can be improved. 相似文献
99.
Fan Yang Jie Ruan Yijun Zhao Linfeng Zhu Xiaohao Wang Guangjie Chen 《Translational andrology and urology》2022,11(9):1345
BackgroundUrethrocutaneous fistula (UCF) remains the most common complication after hypospadias repair, and the recurrence rate of UCF is still high if the surgical techniques is not chosen properly, which called for better approaches to this problem. UCF presents different clinical characteristics due to their different locations and sizes, therefore we retrospectively analyzed the effects of different surgical techniques on single UCF after hypospadias repair in order to reduce the recurrence rates of UCF.MethodsA total of 602 patients diagnosed with UCF after hypospadias repair from January 2014 to December 2021 were enrolled. Baseline clinical characteristics such as age of patients, UCF location, size, surgical techniques were recorded. Patients were followed up in the outpatient clinic. The recurrence of UCF was defined as outcomes. Patients were divided according to the location of the UCF into a coronal UCF group and a non-coronal UCF group, which was then further classified according to the diameter of the UCF. The surgical technique and the recurrence rate of different types of UCF were analyzed and summarized.ResultsA total of 425 patients satisfied the inclusion criteria and 71 patients (16.7%) had recurrent UCF. Five surgical techniques were used to repair the UCF, namely tubularized incised plate (TIP) urethroplasty, Mathieu urethroplasty, double ligation, simple classical closure and trap-door procedure. The recurrence rate was 24.1%, 14.3%, 15.1%, 16.7%, and 22.2%, respectively. TIP or Mathieu urethroplasty is recommended for patients with coronal UCF with glans dehiscence or patients with coronal UCF diameter ≥4 mm without glans dehiscence. In patients with coronal UCF without glans dehiscence, double ligation is recommended for small UCF with diameter <2 mm, and simple classical closure is recommended for UCF with diameter 2–<4 mm. In patients with non-coronal UCF, double ligation is recommended for UCF with diameter <3 mm, and simple classical closure is recommended for UCF with diameter ≥3 mm.ConclusionsSingle UCF can be classified according to the location and size of the UCF. Different types of UCF should be treated with more appropriate individualized strategies, which can effectively reduce the recurrence rate of UCF. 相似文献
100.
Haoyu Zhao Hongjiang Ruan Yuting Cao Hengfeng Yuan Qinglin Kang 《Orthopaedic Surgery》2022,14(12):3417
ObjectiveThe outcome of congenital clubfoot treatment is still challenging if the feet deformities are not completely corrected. Here we explore a minimal invasive procedure with an eight‐plate implant to correct the residual forefoot adduction deformity after treatment of neglected or relapsed clubfoot.MethodsWe retrospectively reviewed patients with residual forefoot adduction deformity after clubfoot treatment between January 2013 and June 2016. The patients underwent temporary epiphysiodesis of the lateral column of the mid‐foot, which in detail, an eight‐plate was placed on each side of the calcaneocuboid joint. The foot deformities were recorded according to the weight‐bearing radiographic measurements including talo‐first metatarsal angle, calcaneo‐fifth metatarsal angle and medial‐to‐lateral column length.ResultsA total of 13 patients (20 feet) with an average age of 7.8 years old were located with an average duration of 40.8 months follow‐up (range, 28 to 54 months). The average talo‐first metatarsal angle improved from 28.3° (range, 19° to 47°) preoperatively to 8.3° (range, 3° to 18°) and the calcaneo‐fifth metatarsal angle improved from 29.1° (range, 19° to 40°) preoperatively to 8.4° (range, 0° to 21°) at final follow‐up. The mean ratio of the medial‐to‐lateral column length improved from 1.14 ± 0.06 to 1.55 ± 0.09 with statistical significance (t = 3.566; P < 0.001).ConclusionsEight‐plate epiphysiodesis is an easy and effective method for the correction of residual forefoot adduction deformity after clubfoot treatment in growing children without the need of osteotomy. 相似文献