Variability of the Schirmer tear test values in a normal Arab population

Background: As in many parts of the world, the Schirmer tear test is the main test used by optometrists in Saudi Arabia for assessing adequacy of tear production. Variability of the test has been reported in different ethnic groups but not in Arabs. This paper looks at the mean and repeatability of the values obtained by the Schirmer test in a normal Arab population Method: The test was performed on the right eyes of 23 young adult Saudi male subjects at five visits over two weeks. Result: Results showed that for each subject the test values were not repeatable, varying widely over the period of evaluation. The mean value was estimated at 10.6 mm and the 95 per cent confidence limits were 7.9 and 13.3 mm. It was also established that the greater the amount of tears, the greater the variability. Conclusion: This study supports the claim that the Schirmer test is not repeatable and hence is unreliable. Therefore, caution should be exercised in employing it for clinical diagnosis. (Clin Exp Optom 1995; 78: 5: 190–193)     

正常人口腔粘膜不同部位表面感觉的测试

目的 建立正常人口腔粘膜不同部位表面感觉的正常参考值，并测试各年龄组感觉值是否存在差异。方法 利用动静两点辨别觉试验，测试90例健康人口腔粘膜不同部位的表面感觉。结果 舌尖感觉功能最好，其次为舌背、舌腹、颊粘膜、口底和硬腭。健康人的口腔粘膜不同部位的表面感觉随着年龄增长有显著性变化。结论 口腔粘膜不同部位感觉辨别力存在差异，健康人口底、舌腹、舌背、颊和硬腭粘膜感觉功能有增龄性变化。     

Fluid shear induced endothelial cell detachment from glass - influence of adhesion time and shear stress

In this study, human umbilical vein and human saphenous vein endothelial cells were seeded on glass and exposed to fluid shear in a parallel-plate flow chamber. Cell retention, morphology and migration were studied as a function of shear stress and of adhesion time prior to exposure to shear. Three-hour and 24-h adhesion times gave rise to comparable cell retention values after 2 h of flow for both cell types. Cell retention decreased from 85 to 20% as shear stress increased from 88 to 264 dynes cm⁻² (8.8 to 26 Pa). Mean spreading areas decreased after the onset of flow, but subsequently stabilized to plateau values, which were smaller at higher shear stresses. Shape factors increased faster to higher values as cells were exposed to higher shear stresses, without any obvious preference in orientation of the cells with respect to the direction of flow. Migration was unidirectional with flow and linear with time. Migration was faster for cells which had adhered for 24 h than for cells which had adhered for 3 h and was accompanied by the presence of fibrillar structures left behind on the surface upstream of migrating cells. It is concluded that after 3 h adhesion to glass, cells have adhered with an adhesion strength that does not substantially increase during the next 21 h. However, during this time changes in cell-substratum interactions seem to occur judging by the differences in, e.g., migration rates.     

Effect of ethanol on sustained attention in rats

 Acute exposure to ethanol produces deficits in sustained attention in humans, but these attentional deficits have not been modeled in animals. In this study, an operant task was used to investigate the effects of low and moderate doses of ethanol on sustained attention in rats. Performance on a two-choice reaction time task over a 1-h session was assessed immediately following administration of ethanol (0.0, 0.5, 0.75, 1.0 and 1.5 g/kg IP). Each rat was required to respond to a light stimulus of variable duration (20, 100, and 500 ms) occurring at one of two locations. Under control and saline conditions, increases in stimulus length systematically increased choice accuracy and decreased reaction time. Ethanol produced a dose-dependent decrease in choice accuracy that interacted with time, with an initial impairment that was stimulus length-dependent followed by a general vigilance decrement. The data demonstrate that ethanol impaired the ability of rats to direct and sustain attention to brief, infrequent stimuli, and provide a model for further investigations into the underlying neurobiological mechanisms for ethanol-induced attentional deficits. Received: 19 March 1996 / Final version: 30 August 1996     

Pronounced bronchial hyper-responsiveness and asthma severity

Summary. Fifty-six asthmatics from an asthma ward or from an asthma out-patient clinic were challenged with two low concentrations (0–03 and 0–012 mg) of metacholine chloride in order to assess the relationship between pronounced hyper-responsiveness and asthma severity in a clinical setting. Only inhaled bronchodilators were stopped before challenge. Asthma severity was assessed retrospectively and prospectively on the basis of treatment, number of days in hospital, intensive care, number of emergency visits and days on sick-leave. The results show that pronounced hyper-responsiveness (n= 28) is not associated with asthma severity. It is concluded that a single simplified test of pronounced bronchial hyper-responsiveness, performed without taking into consideration the actual state of the disease and without stopping all medication, is of no help in identifying the patients with the clinically most severe asthma and worst prognosis.,     

应用羧化胶乳凝集试验诊断人、畜布鲁氏菌病的研究

应用以化学交联法制备的布鲁氏菌１６Ｍ抗原－羧化胶乳制剂的羧化胶乳凝集试验（ＬＡＴ）、试管凝集试验（ＳＡＴ）、虎红平板凝集试验（ＲＢＰＴ）以及酶联免疫吸附试验（ＥＬＩＳＡ）、半胱氨酸凝集试验（ＣＹＴ），对在四省布鲁氏菌病疫区收集的部分人、畜血清中布氏菌抗体进行对比检测。结果表明，ＬＡＴ较之ＲＢＰＴ具有更高的特异性；与ＳＡＴ相比，无论阳性或阴性符合率均较一致。另外，ＬＡＴ可检测血清中ＩｇＧ、ＩｇＭ两类布氏菌特异性抗体。因而本试验对人、畜布病的诊断具有特异、敏感和简便的优点，更宜在基层推广应用。     

The desipramine-induced growth hormone response and the dexamethasone suppression test in obsessive-compulsive disorder.

Ten patients with DSM-III-R obsessive-compulsive disorder (OCD) underwent the desipramine (DMI) growth hormone (GH) stimulation test as well as the dexamethasone suppression test (DST). The results were compared with the responses in a group of matched healthy controls. The GH response to DMI did not differ between patients and controls and 9 of 10 patients showed cortisol suppression in response to dexamethasone. The data suggest that neither alpha 2 adrenergic dysfunction nor DST non-suppression are features of primary OCD.     

改良锂清除试验──一种在人体测量肾小管钠转运功能的方法

在常用的七小时锂清除试验方法基础上，我们观察了实验开始后第四小时血清理浓度与血清理代表浓度的关系，二者密切相关，ｙ＝０．９０９ｘ＋０．１７，ｒ＝０．９５２，Ｐ＜０．００５。应用此方程式，可将原方案中两次取血减为一次。另外，我们还总结出正常人锂清除率和锂排泄分数的参照值分别为８．４～３１．６ｍｌ／ｍｉｎ和９．６％～２６．３％。     

赤灵芝的致突变性试验

使用赤灵芝的水提取液、乙醇（３０％）提取液进行鼠伤寒沙门氏菌回复、小鼠骨髓多染红细胞微核和雄小鼠精子畸变等三种致突变试验。剂量为１０００μｇ．皿＾－１和５０００μｇ／皿＾－１的鼠伤寒沙门氏菌回复试验的结果为阴性。小鼠在服用７５００ｍｇ．ｋｇ＾－１的水提取液或２５００ｍｇ．ｋｇ＾－１的醇提取液时，微核试验和精子畸变试验结果均为阴性。