Anterior eye focusing of peripheral ultraviolet and visible radiation albedo

Concern about short- and long-term ultraviolet radiation (particularly UVB) damage to the eye has led to increased research in this area. Numerous studies have confirmed the pathogenic enhancing roles of reflected ultraviolet (UV) and visible radiation in our environment. There is concern that conventional sunglasses do not protect the eye adequately from reflected rays (albedo), especially on the lateral aspect, from behind and from below. Using eye models and computer ray tracing methods, the pathways of oblique rays incident at the temporal peripheral cornea have been plotted by Maloof, Ho and Coroneo.¹ These rays are refracted and focused and theoretically can result in up to 20 times the concentration of incident irradiance at the nasal anterior chamber angle and nasal equatorial cortex of the crystalline lens. The purpose of this study was to determine the limits of angular subtense of the incident peripheral light which is refracted in this manner in human subjects and to investigate the relation between corneal shape and certain ocular parameters to the limits. A statistically significant positive correlation was found between temporal entrance angle and anterior chamber depth (r = 0.70, P< 0.0006). The entrance angle ranged from 15 degrees to 30 degrees and was located 10 degrees to 45 degrees posterior to the coronal plane. Our results support Maloof and colleagues' predictions for the implication of focused peripheral UV and high intensity visible radiation in the pathogenesis of pterygium and cortical cataract and emphasise the need for lateral eye protection in conditions of high ultraviolet albedo.     

开式涡轮转盘塔的操作区域

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。     

Laparoscopic trans-cystic-duct common-bile-duct exploration

One thousand seventy-one consecutive laparoscopic cholecystectomies were performed. Routine cholangiography was employed with a 99% success rate. One hundred thirty patients were found to have common duct stones (CBDS). In 48 (37%) patients they were unsuspected. One hundred eleven patients underwent attempted trans-cystic-duct extraction techniques (TCD-CBDE). One hundred three (93%) were successful. The following techniques were employed: 101—biliary endoscopy, 23—ampullary balloon dilation, 2—fluoroscopic basket retrieval.The average operative time was 136 min. The average postsurgical stay was 3.7 days. There were 19 (17%) complications—6 (5%) major. There were 4 retained stones (2 intentional) and 1 death. Patients over 65 years of age had more complications and patients with unsuspected CBDS under 65 years of age had the fewest.TCD-CBDE is a safe, effective way to extract common duct calculi. Endoscopy and basket stone retrieval was the primary technique employed.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Nashville, Tennessee, USA, 18–19 April 1994     

劈裂技术在白内障超声乳化术中的应用

目的：探讨劈裂技术在白内障超声乳化术中的应用。方法：运用劈裂技术治疗白内障及囊袋内植入人工晶体462例(516眼)。参数设定：能量50％～70%，负压150～l80mmHg(1mmHg=0．133kPa)，流量24ml／min。结果：超声平均时间1．3min，最短0．4min，术后1天裸眼视力≥0．5者占69％，≥1．0者21％。术后1周最佳矫正视力≥0．5者占78％，≥1．0者25％。术中后囊破裂14只限。术后角膜轻度水肿59只眼，1周内消退。结论：劈裂技术具有使用能量低、超声时间短等优点，是目前较理想的机械性碎核方法。     

无痛麻醉在拔牙术中的临床应用

目的：评价无痛麻醉技术的临床麻醉效果，寻求一种更有利于手术进行的局麻技术。方法：选择120例就诊于齿槽外科门诊需要拔牙的患者，将其随机分为对照组和实验组，每组60例。对照组施常规局麻，实施组施无痛麻醉技术，观察每组麻醉结束、术中及术后的血压、心率变化。结果：对照组与实验组对比，术中、术后观测指标的变化无显著性差异，麻醉结束后的观测指标15以下者无显著性差异，15岁以上者有显著性差异。结论：无痛麻醉技术与常规的局麻技术一样可以达到麻醉的目的，无痛麻醉可减少麻醉注射中因疼痛所引起的血压、心率的变化。     

实验性D—半乳糖诱发动物白内障造模的探讨

用D—半乳糖餵饲、腹腔及球后注射诱发白内障造模,经裂隙灯检查结果表示,30％D—半乳糖餵饲大鼠造模是一种简单有效的方法。     

超声波提取快速测定复混肥料中的水溶性磷

研究超声波提取复混肥料中水溶性磷的方法及提取条件对测定结果的影响,该方法与国家标准GB150632001《复混肥料》中规定的方法比较,操作简单、省时,准确度较高,RSD值小于0.5%。     

白内障形成机制研究

通过对老年性白内障、外伤性白内障、先天性白内障(共14例)及正常晶体(20例)的SOD测定,表明晶体内自由基产生增加,抗氧化能力障碍是白内障形成的重要原因之一。同时,对晶体内自由基的发生及致病机理进行了探讨,提示在白内障形成初期,给予抗氧化制剂在可能阻止或延缓白内障形成。     

A rapid solid-phase extraction and HPLC/DAD procedure for the simultaneous determination and quantification of different benzodiazepines in serum,blood and post-mortem blood

Summary A rapid and quantitative method for the determination of benzodiazepines using high-performance liquid chromatography (HPLC) with diode-array detection (DAD) is reported. The drugs were extracted from serum, blood or post-mortem blood using C₁₈ extraction columns. Brotizolam was used as internal standard. Experiments with spiked serum/blood samples resulted in recoveries between 75% and 94% for all investigated benzodiazepines. Excellent linearity was obtained over the concentration range 5–1500 ng benzodiazepine/ml. The limit of detection was approximately 2 ng/ml. The detection of low therapeutic serum levels of highly potent benzodiazepines is also possible.