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991.
目的 分析高度近视眼白内障手术效果。方法 高度近视合并白内障病例共191 例(279 只眼),行白内障术后3mo以上,随访视力、眼屈光度及并发症,计算测量误差及SRK-II公式误差。结果 术后矫正视力0 .5 者200 只眼,占71.7 % ;矫正视力< 0.1 者13 只眼,占4 .7 % - 眼轴越长,近视性眼底病变越重。术后发生视网膜脱离2 只眼(0 .7%) 。眼轴长度测量误差值平均为0.53mm ,SRK-II公式计算的平均绝对屈光误差值为1.12D。结论 高度近视眼白内障手术效果较一般人群差,且眼轴越长效果越差。 相似文献
992.
眼铁质沉着症临床分析:附7例报告 总被引:1,自引:0,他引:1
探讨眼铁质沉着症对眼组织的损害,诊断及常见误诊原因,方法对7例眼铁质沉着症临床资料进行分析。结果6例经手术治疗者随访视力0.3-0.8,但眼底,视野,眼底荧光血管造影及ERG检查均显示视网膜,视神经有不同程度的损害。结论眼铁质沉着症常因误诊,漏诊引起,重在预防。 相似文献
993.
Inhibition of herpes simplex virus type 1 and adenovirus type 5 by heterocyclic Schiff bases of aminohydroxyguanidine tosylate 总被引:3,自引:0,他引:3
Eleven heterocyclic Schiff bases of aminohydroxyguanidine tosylate (SB-AHGs), compounds I-XI, were tested for antiviral activity against herpes simplex virus type 1 (HSV-1) and adenovirus type 5 (Ad 5) via plaque reduction and virus yield reduction assays. This work was undertaken to test the hypothesis that low molecular weight SB-AHGs (MW < 235 for the free SB) make better antiviral agents than high MW SB-AHGs (MW > 300). The plaque reduction assay method demonstrated that three compounds, I, VII and IX, had moderate activity against HSV-1, with 50% inhibitory concentration (IC50) values of 38.0, 23.5 and 52.1 microM, respectively. Against Ad 5, compounds I, VIII and XI exhibited moderate activity, with IC50 values of 52.7, 19.3 and 5.1 microM, respectively. Among the compounds screened, compound I (1-[(3'-hydroxy-6'-methyl-2'-pyridyl)methylene]amino-3-hydroxyguanidi ne tosylate) was the most promising antiviral candidate, with selectivity indices (SI) of 10.2 (HSV-1) and 7.6 (Ad 5), respectively. Virus yield reduction assays indicated that compound I had less antiviral potency against HSV-1 than against Ad 5. The antiviral effects of compound I at a high input virus multiplicity of infection (MOI > 5) indicated that compound I had effective anti-adenoviral activity at 24 h post infection. This work demonstrated that some of SB-AHGs only have moderate antiviral activities against Ad 5 and HSV-1 viruses. In general, low MW SB-AHGs have low cytotoxicities to the host cells. 相似文献
994.
阿芙唑嗪及多沙唑嗪十二指肠给药及对猫尿道压的选择性作用 总被引:1,自引:0,他引:1
目的观察不同给药途径对芙唑嗪(Alf)和多沙唑嗪(Dox)降尿道反压的选择性作用。方法 电刺激麻醉猫腹下神经以长高尿道压,比较十二指肠和静脉两种途径给药时,Alf和Dox降低平均动脉血压(MBP)及尿道压(UP)的作用。结果:相同电刺激条件(10Hz,25V)Alf肠道给药与静脉给经时ED20(BP)/ED50(UP)比值为10.9:4.3;Dox两种给药途径的比值为3.1:2.1,Alf十二指肠 相似文献
995.
目的:动态观察大鼠C6胶质瘤模型的自然生长过程及反义IGF-1mRNA对胶质瘤的治疗效果和治疗机制。方法:将32只Wistar大鼠分成4组,每组8只,(1)对照组(C组)于右尾状核接种C6鼠胶质瘤细胞。(2)治疗组(T组):于右尾状核接种C6细胞后的第7、10天在接种点注射脂质体包裹的质粒P-anti-IGF-1,对胶质瘤进行治疗于右尾状核接种经反义IGF-1mRNA转染的C6胶质瘤细胞。(4)K 相似文献
996.
平阳霉素联合地塞米松治疗颌面部大面积海绵状血管瘤 总被引:4,自引:0,他引:4
目的:观察平阳霉素(PYM)联合地塞米松(DXM)治疗颌面部大面积海绵状血管瘤的临床疗效和不良反应。方法:对9例临床确诊的颌面部范围6cm×7cm~10cm×12cm之间的大面积海绵状血管瘤,采用每周1次多点多方向瘤腔内注射药物,比较治疗前后患者的反应和肿瘤的形成变化。结果:全部病例肿瘤消失,无明显不良反应,经8个月~46个月观察,临床治愈率为100%。结论:PYM联合DXM能够治愈颌面部大面积海绵状血管瘤,具有完整保存组织正常形态和功能的特点,克服了单独使用PYM带来的不良反应,提示两药在治疗上有协同作用。 相似文献
997.
Smith Geoff Shekunov Boris Yu. Shen Jie Duffy Alistair P. Anwar Jamshed Wakerly Mark G. Chakrabarti Roma 《Pharmaceutical research》1996,13(8):1181-1185
Purpose. A knowledge of the interfacial properties of lecithin underpins our understanding of many of the physicochemical characteristics of drug delivery systems such as liposomes and lecithin stabilized microemulsions. In order to further this understanding, a high frequency dielectric study of the interfacial properties of egg lecithin liposomes was undertaken.
Methods. The effect of temperature, lecithin concentration and probe sonication on the interfacial dielectric properties of liposomal suspensions was investigated by high frequency dielectric relaxation spectroscopy between 0.2–6 GHz.
Results. The frequency dependent permittivity of each suspension exhibited a dielectric dispersion centred around 100 MHz, corresponding to the relaxation of zwitterionic head groups. The activation energy for head group reorientation was estimated as H = 6.3 kJ mol–1. There was an increase in extent of inter-head group interactions on increasing the liposome volume fraction, whereas the effect of probe sonication showed that: (i) head groups in both the outer and inner lamellae contribute to the dielectric response; (ii) the head groups may be less restricted in liposomes of high surface curvature with few lamellae; (iii) the high frequency permittivity of the suspension increased on sonication, as a result of a reduction in the amount of (depolarized) interlamellar water following a reduction in the number of lamellae per liposome.
Conclusions. Dielectric analysis of the zwitterionic head groups of lecithin therefore provides a means for investigating the surface of lecithin liposomes, and may be used to investigate the effect of drugs and other solutes on membranes. 相似文献
998.
999.
Yves Bécouarn Binh Nguyen Bui René Brunet Alain Ravaud 《Cancer chemotherapy and pharmacology》1991,29(2):159-163
Summary A total of 2,238 new cancer patients were treated in our institution in 1988; among the 423 (18.9%) who were>70 years old, 51 underwent chemotherapy. The median age was 75.8 years, and the Karnofsky performance status (KPS) was 70% for 40 patients. Malignancies were hematopoietic in 24 cases (47%) and digestive in 15 patients (29%), and 12 subjects (24%) had other types of cancers. The first chemotherapy course was given at the full dose to 23/51 (45.1%) patients. The drug dose was reduced for 28/51 (54.9%) patients, due in 25 cases to the subjects being>70 years old. Neither age, KPS, pretreatment assessment, nor cancer extent was correlated with the modifications made to the first cycle. An overall toxicity of grade 3+4 (WHO grading scale) was noted in 10 subjects (19.6%). Although these elderly patients were probably selected, analysis of their charts did not evidence an increase in chemotherapy toxicity, regardless of the dose they received.Presented at the EORTC Pharmacokinetics and Metabolism Group Meeting, Bordeaux, November 1990 相似文献
1000.
Piotr Kruszewski Maria Luisa Fasano AIf O. Brubakk Jie Ming Shen Trond Sand Ottar Sjaastad 《Headache》1991,31(6):399-405
The recently described "Sunct" syndrome is a rare picture of unilateral, shortlasting headache attacks accompanied by autonomic phenomena (conjunctival injection, tearing, etc.) on the symptomatic side. Heart rate and blood pressure were monitored in two elderly "Sunct" patients during and outside headache attacks. An ultrasound Doppler servo method was used for the non-invasive, continuous, beat-to-beat determination of instantaneous arterial blood pressure. In a third patient, systolic and diastolic blood pressure, both outside and during pain paroxysms, were assessed using the standard Korotkoff method. Heart rate was found to be significantly decreased during pain paroxysms. Systolic blood pressure was observed to be significantly increased during attacks, when compared with the inter-attack period, while a less consistent pattern was observed for diastolic blood pressure. Some of the changes in the cardiovascular system seemed to start prior to pain onset. Therefore, it seems unlikely that these changes were caused by pain activation of the sympathetic nervous system or the oculocardiac reflex. 相似文献