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21.
To investigate a simple method during extracapsular cataract extraction with posterior chamber intraocular lens implantation in order to reduce surgically induced corneal astigmatism.Methods: A modified scleral flap incision was used in the extracapsular cataract extraction with intraocular lens implantation and the postoperative changes in conreal astigmatism was observed.Results: The peak value of postoperative corneal astigmatism was 3. 60 D, and the corneal astigmatism regression was 2. 11 D, surgically induced astigmatism was less significant in modified scleral flap incision group than that in conventional limbal incison group (P<0. 05).Conclusions: The modified scleral flap incision is an ideal incision for cataract extraction with intraocular lens implantation when phacoemulsifier is not available. Eye Science 1995; 11-. 136-139.  相似文献   
22.
从芫花Daphne genkwa条的乙酸乙酯可溶部分分到3个结果性化合物,借助于波谱分析手段推断出Ⅱ为西瑞香素,Ⅲ为daphnodorin B。  相似文献   
23.
Summary The total body clearance and fractional extraction of isoprenaline (ISO) have been determined, and the relation between these parameters and cardiac output established. Whether desipramine, an inhibitor of neuronal uptake, altered the plasma catecholamine response to ISO was also investigated.Seven healthy subjects were given i.v., infusions of ISO in two, consecutive 25-min periods, at constant dose rates of 31–43 and 80–124 pmol·kg–1·min–1, respectively. The total-body (ER), pulmonary (ERp) and forearm (ERf) fractional extractions and the total body clearance (CL) of ISO were obtained from measurements of cardiac output and the steady-state ISO concentration in mixed central venous, arterial and forearm venous plasma.ISO-induced increases in cardiac output resulted in increases in CL, decreases in ER and no consistent change in ERf. ERp did not differ from zero. ISO also produced a dose-dependent increase in the mixed venous plasma concentrations of noradrenaline and 3,4-dihydroxyphenylglycol (DOPEG), and a decrease in that of adrenaline. Pretreatment with desipramine did not alter any of the pharmacokinetic parameters of ISO. Desipramine, however, reduced the mixed venous baseline plasma levels of noradrenaline (47%) and DOPEG (40%), and tended to reduce that of adrenaline (34%). It enhanced the plasma noradrenaline response 2.4-fold, abolished the plasma DOPEG response and did not alter the plasma adrenaline response to ISO.Hence, owing to its haemodynamic effects, ISO modifies its own pharmacokinetics which involve non-neuronal removal processes only. The increased DOPEG in plasma resulting from the ISO-induced increase in noradrenaline release was presynaptic in origin. Desipramine appears to reduce sympathetic activity. The enhancement by desipramine of the ISO-induced increase in plasma noradrenaline points towards recapture by neuronal uptake of at least 58% of the noradrenaline released in response to ISO.  相似文献   
24.
目的 :测量在 4个区分别拔除 1个前磨牙后的 Bolton指数全牙比。方法 :选取 5 8例拔除 4个前磨牙正畸治疗后的满意病例 ,测量模型的牙齿宽度 ,计算其 Bolton指数全牙比。结果 :拔除 4个前磨牙正畸满意病例的 Bolton指数全牙比为 90 .5 0 %± 1 .60 %。结论 :本文测得的拔除 4个前磨牙的病例治疗后的 Bolton指数全牙比对临床具有一定参考意义。  相似文献   
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采用聚偏氟乙烯固体微孔膜,与溶解在煤油中的三烷基氧磷组成支撑液膜(SLM),分离稀水溶液中的乳酸。考察了pH值、料液浓度、载体浓度、温度、料液及解析液流量对传质速率的影响。同时进行了膜稳定性的定性研究。发现乳酸以分子形式通过SLM;载体浓度为40%时传质速率最大;SLM对乳酸的通量与稀水溶液中乳酸浓度成正比。料液和解析液预先用有机相饱和时,膜的稳定性可大大改善。  相似文献   
28.
Abstract A periodontally affected tooth was prepared for a special treatment: Calcium hydroxide was introduced into the apical half of the root canal whereas its cervical part was filled with glass ionomer cement. The tooth was shortened subgingivally. After 6 weeks of epithelization over the residual root a palatal full-thickness flap was mobilized. The root was carefully extracted and chairside copy-milled from the biodegradable polylactic acid (PLA) material. The PLA-replica was implanted immediately into the socket and the flap was sutured. Aim of the treatment was to prevent the ridge collapse of the extraction area. Ridge height could be preserved during the 21 months of observation. With time the radiographic density of the cancellous bone increased in the implanted area, indicating that a PLA-replica is replaced by host's bone tissue.  相似文献   
29.
考察了开式涡轮转盘塔(OTRDC)中的分散相滞留率和液泛特性。采用五种不同的液-液体系,在两种不同直径的塔中进行了实验。给出了估算分散相滞留率的关联式及无传质时临界转速的判据,进而大体上确认了OTRDC的操作区域。  相似文献   
30.
Abstract: Extraction of adsorbed proteins from dialysis membranes that had been used during actual hemodialysis procedures was performed. The condition of extraction with SDS plus 2–mercaptoethanol at 95°C is more efficient than with only PBS or with SDS solution without 2–mercaptoethanol at 37°C.  相似文献   
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