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991.
采用薄层扫描法分别测定了12批穿心莲商品药材中茎和叶所含穿心莲内酯和脱水穿心莲内酯的含量,并进行了比较,结果其总量在茎中平均占0.29%,在叶中平均占2.26%.因此建议穿心莲中叶所占比例应不少于35%.  相似文献   
992.
The purpose of this study was to develop and optimize the propranolol once-daily extended release formulations containing HPMC, Microcrystalline cellulose (MCC) and lactose. In vitro studies, the response surface methodology and multiple response optimization utilizing the polynomial equation were used to search for the optimal formulation with specific release rate at different time intervals. The constrained mixture experimental design was used to prepare systematic model formulations, which were composed of three formulation variables: the content of HPMC (X(1)) MCC (X(2)) and lactose (X(3)). The drug release percent at 1.5, 4, 8, 14 and 24 h were the target responses and were restricted to 15-30, 35-55, 55-75, 75-90 and 90-110%, respectively. The results showed that the optimized formulation provided a dissolution pattern equivalent to the predicted curve, which indicated that the optimal formulation could be obtained using response surface methodology. The mechanism of drug release from HMPC matrix tablets followed non-Fickian diffusion. In the vivo study, the MRT was prolonged for matrix tablets when compared with commercial immediate release tablets. Furthermore, a linear relationship between in vitro dissolution and in vivo absorption was observed in the beagle dogs.  相似文献   
993.
Notexin, a presynaptic phospholipase A2 (PLA2) neurotoxin isolated from Notechis scutatus scutatus venom, was inactivated by arginine-specific reagents, phenylglyoxal and 1,2-cyclohexanedione. Kinetic analyses of the modification reaction revealed that the inactivation of notexin followed pseudo-first order kinetics and the loss of PLA2 activity was correlated with the incorporation of one molecule of modification reagent per toxin molecule. However, the results of amino acid analysis and sequence determination revealed that two arginine residues at positions 43 and 79 of notexin were modified simultaneously. Modification of the arginine residues was accompanied with a decrease in the ability to inhibit the indirectly evoked contraction of chick biventer cervicis muscle and bind with synaptic membranes. The secondary structure of the toxin molecule did not significantly change after modification with phenylglyoxal as revealed by the CD spectra. The modified derivative retained its affinity for Ca2+, indicating that the modified arginine residues did not participate in Ca2+ -binding. Together with the notion that Arg-43 and Arg-79 of notexin are located in the proximity of its catalytic site and toxic site, respectively, our results suggest that modification of Arg-43 and Arg-79 should differently contribute to the observed decrease in the PLA2 activity and neurotoxic effect of notexin.  相似文献   
994.

目的:采用Keratograph 5M眼表综合分析仪比较小梁切除术和超声乳化白内障摘除联合小梁切除术对眼表的影响。

方法:纳入原发性闭角型青光眼合并白内障患者62例62眼,按手术方式分为两组:小梁切除术组32例32眼,超声乳化白内障摘除联合小梁切除术组(青白联合手术组)30例30眼。运用Keratograph 5M评估术前,术后3d,1、 3mo的非侵入性首次泪膜破裂时间(NifBUT)、非侵入性平均泪膜破裂时间(NiaBUT)、泪河高度(TMH)和角膜荧光素染色评分(CFS)。

结果:术前两组患者眼表参数比较差异均无统计学意义(P>0.05)。术后3d青白联合手术组的NiaBUT、NifBUT、CFS、TMH最差,分别为10.13±1.48、12.59±1.96s、0.80±0.22分与0.31±0.02mm,变化幅度明显高于小梁切除组(均 P<0.05),术后1mo两组的各项指标均有所恢复,但直到术后3mo仍未完全恢复到术前水平。

结论:眼表综合分析仪可以客观、精确地用于评估抗青光眼手术后泪膜功能的变化。在术后3mo短期内超声乳化白内障摘除联合小梁切除术比单纯小梁切除术对眼表的影响更为严重,提示在此期间应加强对眼表的护理。  相似文献   

995.

目的:探讨分析糖尿病视网膜病变(diabetic retinopathy,DR)患者全视网膜激光光凝术(panretinal photocoagulation,PRP)治疗后1a视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度的变化。

方法:选取2014-05/2017-06在我院行PRP治疗的92例92眼DR患者,采用OCT的DISC CIRCLE程序,测量分析以视盘为中心、直径3.45mm范围DR患者PRP术前和术后1a(采用Follow-Up程序自动追踪模式)视盘周围RNFL厚度,按视盘上方(S)、下方(I)、鼻侧(N)、颞侧(T)4个象限分区所得的数值进行统计分析。

结果:DR患者PRP术后1a较术前视盘周围上方、下方、鼻侧、颞侧和全周平均RNFL厚度明显变薄,且差异有统计学意义(均P<0.05)。

结论:PRP治疗可导致视网膜RNFL变薄,临床上应充分重视和考虑RNFL的损伤,更好地保护视网膜神经细胞的机能对DR治疗具有重要意义。  相似文献   

996.
AIM: To evaluate the efficacy and safety of intravitreal injection of conbercept in patients with neovascular age-related macular degeneration (AMD). METHODS: Retrospective review of 66 eyes of 63 patients with neovascular AMD. All patients received 0.5 mg intravitreal injections of conbercept monthly for 3 consecutive months, and then pro re nata treatment was performed. The changes of best-corrected visual acuity (BCVA) and central macular thickness (CMT) were observed before and after treatments. Minimum follow-up time was 12mo. SPSS 22.0 statistical software was used for statistical analysis. RESULTS: The mean BCVA and CMT of 66 eyes (63 patients) were 1.11±0.60, 533.20±219.95 μm at baseline, and were 0.68±0.38, 310.28±125.60 μm at 3mo. No subjects were lost during the first three months, the improvements were all significantly (P<0.05). During the whole follow-up time of 12mo, 15 subjects (18 eyes) were lost. The mean BCVA and CMT of the rest 48 eyes with the follow-up time at least 1y were 0.83±0.46 and 547.59±196.77 μm at baseline, after 3mo and 12mo of conbercept injections became 0.55±0.41, 318.24±141.29 μm and 0.55±0.51, 333.87±173.25 μm. The differences were significant (P<0.05). No serious complications were observed. CONCLUSION: Intravitreal injection of conbercept appears to significantly improve visual acuity and anatomical outcomes in patients with neovascular AMD, no serious adverse reactions and complications are observed.  相似文献   
997.
探究晶状体超声乳化联合人工晶状体(IOL)植入术围手术期瞳孔直径、反应的变化。方法:前瞻性临床研究。收集于2016年1-9月上海交通大学医学院附属第九人民医院眼科行超声乳化联合IOL植入术的连续白内障和高度近视透明晶状体置换患者。采用动态瞳孔测量仪(Metro-vision MONCV3)测量术前、术后1周、术后1个月在4种光照度下(0、1、10和100 cd/m2 )的瞳孔直径,并检测瞳孔反应(如瞳孔初始直径、收缩幅度、收缩潜伏期、收缩持续时间、收缩速度、扩张潜伏期、扩张持续时间和扩张速度等)。采用重复测量方差分析、Pearson相关分析及Spearman相关分析对数据进行分析。结果:共纳入患者53例(53眼)。在4种光照度下,术前瞳孔直径随年龄增加而下降(r0=-0.467,P0<0.001;r1=-0.383,P1=0.005;r10=-0.374,P10=0.006;r100=-0.312,P100=0.023)。 4种光照强度下瞳孔直径手术前后总体差异有统计学意义(F0=206.9,P0<0.001;F1=106.8,P1<0.001; F10=41.7,P10<0.001;F100=36.7,P100<0.001),与术前相比,4种光照强度下瞳孔直径术后1周、1个月均下降(均P<0.001)。手术前后瞳孔反应的初始直径、收缩幅度、收缩和扩张速度总体差异有统计学意义(F初始直径=99.5,P初始直径<0.001;F收缩幅度=36.2,P收缩幅度<0.001;F收缩速度=51.9,P收缩速度<0.001;F扩张速度=23.8,P扩张速度<0.001),与术前相比,术后1周、1个月初始直径、收缩幅度、收缩和扩张速度均下降(均P<0.001)。结论:超声乳化联合IOL植入术后1个月内可引起瞳孔缩小,瞳孔反应的收缩、扩张速度变慢,为IOL设计中确定有效光学区范围提供依据。  相似文献   
998.
目的探讨SBL-3新型区域折射型多焦点人工晶状体(MIOL)植入术后的中期临床效果。 方法前瞻性研究。选取2016年6月至2018年1月在成都爱尔眼科医院诊断为年龄相关性白内障,并行超声乳化白内障吸除联合人工晶状体植入的患者59例(87只眼)为研究对象。根据植入人工晶状体类型的不同分为两组。其中,30例(40只眼)植入SBL-3新型区域折射多焦点人工晶状体为多焦组;29例(47只眼)植入Softec HD单焦点人工晶状体为单焦组。术后随访3~12个月,记录术后裸眼远距离(5 m)、中距离(80 cm)、近距离(40 cm)的裸眼视力,矫正远视力及术后等效球镜屈光度;利用VF-14量表行主观问卷调查;对术后眩光的发生率、日常生活老视眼镜依赖与否进行问卷记录;采用双通道视觉质量分析系统测量客观散射指数(OSI)、调制传递函数截止空间频率(MTF cutoff)、斯特尔比值(SR)、对比度视力(包含100%、20%及9%三种)及调节幅度等指标。单焦组和多焦组两组患者各个指标的比较采用独立样本t检验,术前术后的比较采用配对t检验。 结果单焦组与多焦组患者术后裸眼远距离视力均较术前有显著提高,差异有统计学意义(t=-10.859,-13.382;P<0.05)。多焦组与单焦组术后等效球镜屈光度差异无统计学意义(t=1.370,P>0.05)。多焦组与单焦组患者术后裸眼远距离视力分别为(0.87±0.17)与(0.82±0.21),差异无统计学意义(t=-1.129,P>0.05)。多焦组与单焦组患者术后矫正远距离视力分别为(0.91±0.13)与(0.91±0.14),差异无统计学意义(t=0.081,P>0.05)。多焦组与单焦组患者术后裸眼中距离视力分别为(0.70±0.17)与(0.54±0.22),差异具有统计学意义(t=-3.888,P<0.05)。多焦组与单焦组患者术后裸眼近距离视力分别为(0.71±0.20)与(0.28±0.10),差异具有统计学意义(t=-12.340,P<0.05)。单焦组与多焦点组患者采用VF-14表评分分别为(75.39±10.30)与(97.50±4.50),前者低于后者,差异有统计学意义(t=-9.837,P<0.05)。多焦组与单焦组患者对老视眼镜的依赖程度分别为5%(2/40)与93.6%(44/47),差异有统计学意义(χ2=68.104,P<0.05)。多焦组与单焦组患者术后眩光的发生率分别为7.5%(3/40)与4.26%(2/47),差异无统计学意义(χ2=0.035,P>0.05)。多焦组与单焦组患者的MTF cutoff分别为(24.17±7.68)c/deg与(27.00±10.98)c/deg,差异无统计学意义(t=1.398,P>0.05)。多焦组与单焦组患者的OSI分别为(2.0±0.7)与(1.7±0.8),差异无有统计学意义(t=-2.139,P>0.05)。多焦组与单焦组患者的SR分别为(0.13±0.03)与(0.15±0.06),差异有统计学意义(t=2.130,P<0.05)。多焦组与单焦组患者在100%、20%及9%对比度视力比较,差异均无统计学意义(t=1.545,1.886,1.968;P>0.05)。多焦组与单焦组患者术眼调节幅度分别为(2.30±0.80)D与(1.60±0.70)D,差异有统计学意义(t=-3.600,P<0.05)。 结论SBL-3新型区域折射多焦点人工晶状体可以提供较好的全程视力和视觉质量,术后患者满意度较高。  相似文献   
999.
AIM: To investigate the incidence of abrupt visual loss and its associated factors, during anti-vascular endothelial growth factor (VEGF) treatment for type 3 neovascularization. METHODS: This retrospective study included 137 eyes that were newly diagnosed with type 3 neovascularization. All eyes were treated with anti-VEGF therapy. Abrupt visual loss was defined as loss of 5 or more lines in best-corrected visual acuity (BCVA) in comparison to the previous visit. The incidence and timing of abrupt visual loss as well as the factors associated with it, were determined. In addition, the BCVA at the final follow-up was compared between the eyes with and those without abrupt visual loss. RESULTS: The mean follow-up period was 42.4±18.9mo after diagnosis, and abrupt visual loss was noted in 22 eyes (16.1%) at a mean of 19.6±13.9mo. Abrupt visual loss was found to be associated with subretinal hemorrhage in 11 eyes (50.0%), development of or increase in the height of pigment epithelial detachment with fluid in 8 eyes (36.4%), and tears in the retinal pigment epithelium in 3 eyes (13.6%). The logarithm of minimum angle of resolution (logMAR) mean BCVA at the final follow-up was 2.07±0.67 (Snellen equivalents: 20/2349) and 1.00±0.55 (20/200) in eyes with and without abrupt visual loss, respectively. BCVA was significantly worse in the eyes with abrupt visual loss (P<0.001). CONCLUSION: Abrupt visual loss is noted in 16.1% of patients with type 3 neovascularization and is associated with poor visual outcome. Additional studies are needed to determine how abrupt visual loss can be prevented.  相似文献   
1000.
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