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91.
92.
目的 采用视频跟踪技术考察酒石酸美托洛尔片的溶出行为,为仿制药的质量评价提供新的技术参考。方法 以酒石酸美托洛尔片为模型药物,pH1.2的氯化钠盐酸溶液为溶出介质,采用摄像头视频跟踪直观考察溶出行为;同时测定酒石酸美托洛尔片的溶出曲线并计算相似因子(f2),并对处方组成、比例及其制剂工艺进行剖析。结果 各时间点的视频图显示各企业样品均为溶蚀性崩解,与原研一致;企业A的样品与原研溶出行为最为接近,B、G和J的25 mg规格样品以及企业E、I和J的50 mg规格样品与原研溶出行为存在较大的差异,与溶出曲线获得的结果一致。溶出视频记录的溶散速率和崩解的颗粒大小、形态更直观反映出处方工艺的差异。结论 视频跟踪技术清晰客观地反映了酒石酸美托洛尔片的溶出行为,为溶出质量评价提供新思路新方法。 相似文献
93.
摘要:目的 对比分析乳腺放射状瘢痕(RS)与乳腺癌的临床及超声特征。方法 选取2015年2月—2017年12月经病理科确诊并行乳腺超声检查的40例RS和40例浸润性导管癌(IDC)患者,收集2组患者的基线资料:年龄、月经状态、哺乳史、流产史、病灶侧别、既往同侧乳腺手术史、临床症状;术前乳腺超声检查结果:超声图像(形态、边缘、内部回声、后方回声、周围高回声晕、钙化)、血流信号及弹性评分,比较2组患者间临床及超声特征的差异。以病理诊断为金标准,采用受试者工作特征(ROC)曲线评估彩色多普勒超声联合弹性成像技术对两者的诊断效能。结果 RS组和IDC组临床均多表现为乳腺肿物。与IDC组相比,RS组超声图像多表现为形态尚规则、边缘清晰、周围无高回声晕、内部回声均匀、不伴钙化、无血流信号、后方回声无改变或增强、弹性评分良性(P<0.05)。ROC曲线提示二维超声乳腺影像报告和数据系统分类、彩色血流信号和弹性评分三者联合对RS和IDC的诊断效能较好,曲线下面积(AUC)为0.802(95%CI:0.673~0.930,P<0.05),敏感度为0.833,特异度为0.652。结论 RS组和IDC组的超声特征有差异,彩色多普勒超声联合弹性成像检查对于鉴别诊断2种病变有一定意义。 相似文献
94.
目的:筛选可准确描述三七提取物吸湿过程的数学模型,科学量化吸湿过程。方法:25、35和45℃下,用重量法测试三七提取物吸湿过程动力学曲线和吸附/解吸等温线,并用1stOpt统计分析软件进行拟合,以均方根误差(RMSE),残差平方和(RSS)和决定系数(R^2)为评价指标,筛选最佳拟合模型,结合25、35和45℃下吸附等温线计算吸附热。结果:25、35和45℃下,三七提取物吸湿动力学双指数模型、吸附/解吸等温线Peleg模型拟合效果较好,吸附/解吸等温线都属于第Ⅱ种类型,解吸等温线因较高的平衡含水量而出现明显的滞后现象,该滞后现象属于H3型。随着温度升高这种滞后现象变弱。吸附热随着平衡吸湿量的增大而增大。结论:双指数模型和Peleg模型分别较好地拟合三七提取物的吸湿动力学曲线及吸附/解吸等温线,且吸附/解吸等温线存在滞后现象,该滞后现象随温度升高而变弱,吸附热与平衡吸湿量密切相关。 相似文献
95.
96.
药用植物金荞麦的光合特性研究 总被引:2,自引:2,他引:2
目的:研究金荞麦叶片的光合特性,为提高金荞麦的产量和质量提供依据。方法:自然条件下利用LI-6400型便携式光合系统测定金荞麦品种贵州Ⅰ号和江苏Ⅱ号孕蕾期叶片的光响应及光合日变化进程。结果:金荞麦叶片的光响应曲线符合非直角双曲线方程,贵州Ⅰ号金荞麦的光饱和点和光补偿点均高于江苏Ⅱ号金荞麦,对环境的适应能力较强。金荞麦叶片的净光合速率、光合有效辐射、蒸腾速率和气孔导度的日变化曲线均呈单峰曲线,不存在明显的"午休"现象。相关性分析表明,金荞麦叶片净光合速率与气孔导度、光合有效辐射、蒸腾速率和水分利用效率等呈正相关,与胞间CO2浓度呈负相关。结论:金荞麦为阳生植物,气孔导度、光合有效辐射和蒸腾速率是影响金荞麦叶片净光合速率的主要环境因子。 相似文献
97.
Levy A Sheiner E Hammel RD Hershkovitz R Hallak M Katz M Mazor M 《Archives of gynecology and obstetrics》2006,273(4):203-206
Background: The study was aimed to compare pregnancies complicated with shoulder dystocia, of patients with and without diabetes mellitus.
Methods: A comparison of all singleton, vertex, term deliveries between the years 1988–1999, complicated with shoulder dystocia with
and without diabetes mellitus was performed. Statistical analysis was done using receiver operating characteristic curve analysis.
Results: Using a receiver operating characteristic curve analysis, the area under the curve for birth weight was 0.92 (95% CI 0.90–0.93).
However, for birth weight of 4,000 g the sensitivity was only 56% with specificity of 95%. While comparing shoulder dystocia
between patients with (n=38) and without diabetes mellitus (n=207), neonates of the diabetic patients were significantly heavier (mean birth weight 4,244.2±515.1 vs. 4,051.6±389.5; P=0.008) and had higher rate of Apgar scores lower than 7 at 1 min (50.0% vs. 25.9%; P=0.030), but not at 5 min (2.6% vs. 2.0%; P=0.083) when compared to the non-diabetic group. No significant differences were noted regarding perinatal mortality between
the groups (0% vs. 4.3%; P=0.362). Conclusions: The newborn of the diabetic mother complicated with shoulder dystocia does not appear to be at an increased risk for perinatal
morbidity compared with the newborn of the non-diabetic mother.
Presented in part at the Society for Gynecologic Investigation 50th Annual Scientific Meeting, Washington, DC, 27–30 March
2003. 相似文献
98.
Pamela T. Soliman David Iglesias Mark F. Munsell Michael Frumovitz Shannon N. Westin Alpa M. Nick Kathleen M. Schmeler Pedro T. Ramirez 《Gynecologic oncology》2013
Background
The increasing role of robotic surgery in gynecologic oncology may impact fellowship training. The purpose of this study was to review the proportion of robotic procedures performed by fellows at the console, and compare operative times and lymph node yields to faculty surgeons.Methods
A prospective database of women undergoing robotic gynecologic surgery has been maintained since 2008. Intra-operative datasheets completed include surgical times and primary surgeon at the console. Operative times were compared between faculty and fellows for simple hysterectomy (SH), bilateral salpingo-oophorectomy (BSO), pelvic (PLND) and paraaortic lymph node dissection (PALND) and vaginal cuff closure (VCC). Lymph nodes counts were also compared.Results
Times were recorded for 239 SH, 43 BSOs, 105 right PLNDs, 104 left PLNDs, 34 PALND and 269 VCC. Comparing 2008 to 2011, procedures performed by the fellow significantly increased; SH 16% to 83% (p < 0.001), BSO 7% to 75% (p = 0.005), right PLND 4% to 44% (p < 0.001), left PLND 0% to 56% (p < 0.001), and VCC 59% to 82% (p = 0.024). Console times (min) were similar for SH (60 vs. 63, p = 0.73), BSO (48 vs. 43, p = 0.55), and VCC (20 vs. 22, p = 0.26). Faculty times (min) were shorter for PLND (right 26 vs. 30, p = 0.04, left 23 vs. 27, p = 0.02). Nodal counts were not significantly different (right 7 vs. 8, p = 0.17 or left 7 vs. 7, p = 0.87).Conclusions
Robotic surgery can be successfully incorporated into gynecologic oncology fellowship training. With increased exposure to robotic surgery, fellows had similar operative times and lymph node yields as faculty surgeons. 相似文献99.
目的 对比观察ReSTORSV25T0与ReSTORSN6AD1多焦点人工晶状体(moltifocalintraocularlens,MIOL)植入术后的临床视觉效果。方法 行白内障超声乳化吸出联合MIOL植入术的白内障患者41例(43眼),根据植入的MIOL不同分为两组:SN6AD1组20例(22眼)植入ReSTORSN6AD1MIOL,SV25T0组21例(21眼)植入ReSTORSV25T0MIOL,观察两组患者术前及术后3个月裸眼近视力、裸眼中距离视力(50cm、70cm)及裸眼远视力,绘制离焦曲线,并进行对比敏感度检查、视觉质量及满意度问卷调查。结果 术后3个月两组患者5m裸眼远视力对比差异无统计学意义(P>0.05);SV25T0组患者50cm及70cm的裸眼中距离视力分别为(0.12±0.07)logMAR和(0.17±0.08)logMAR,均明显优于SN6AD1组患者的(0.18±0.08)logMAR和(0.24±0.09)logMAR(均为P<0.05),而SN6AD1组患者33cm的裸眼近距离视力为(0.11±0.08)logMAR,高于SV25T0组患者的(0.16±0.08)logMAR(P<0.05);SV25T0组术后暗视下3.0c·d-1及6.0c·d-1空间频率的对比敏感度优于SN6AD1组,差异均有统计学意义(均为P<0.05);术后问卷调查示两组患者均未出现明显视觉干扰,SV25T0组患者在近距离视力的视近满意度较SN6AD1组低,在中距离和远距离下满意度稍高,但是两组间差异均无统计学意义(均为P>0.05)。结论 ReSTORSV25T0与SN6AD1MIOL均能改善白内障患者术后视力及对比敏感度,ReSTORSV25T0在中距离视力的表现优于ReSTORSN6AD1。 相似文献
100.
Human cytochrome P450 2C9 (CYP2C9) accounts for ∼20% of hepatic total CYP content and metabolizes ∼15% clinical drugs such as phenytoin, S-warfarin, tolbutamide, losartan, and many nonsteroidal anti-inflammatory agents (NSAIDs). CYP2C9 is highly polymorphic, with at least 33 variants of CYP2C9 (*1B through *34) being identified so far. CYP2C9*2 is frequent among Caucasians with ∼1% of the population being homozygous carriers and 22% are heterozygous. The corresponding figures for the CYP2C9*3 allele are 0.4% and 15%, respectively. There are a number of clinical studies addressing the impact of CYP2C9 polymorphisms on the clearance and/or therapeutic response of therapeutic drugs. These studies have highlighted the importance of the CYP2C9*2 and *3 alleles as a determining factor for drug clearance and drug response. The CYP2C9 polymorphisms are relevant for the efficacy and adverse effects of numerous NSAIDs, sulfonylurea antidiabetic drugs and, most critically, oral anticoagulants belonging to the class of vitamin K epoxide reductase inhibitors. Warfarin has served as a practical example of how pharmacogenetics can be utilized to achieve maximum efficacy and minimum toxicity. For many of these drugs, a clear gene–dose and gene–effect relationship has been observed in patients. In this regard, CYP2C9 alleles can be considered as a useful biomarker in monitoring drug response and adverse effects. Genetic testing of CYP2C9 is expected to play a role in predicting drug clearance and conducting individualized pharmacotherapy. However, prospective clinical studies with large samples are warranted to establish gene–dose and gene–effect relationships for CYP2C9 and its substrate drugs. 相似文献