The effect of font size and type on reading performance with Arabic words in normally sighted and simulated cataract subjects

Background: Previous investigations have shown that reading is the most common functional problem reported by patients at a low vision practice. While there have been studies investigating effect of fonts in normal and low vision patients in English, no study has been carried out in Arabic. Additionally, there has been no investigation into the use of optimum print sizes or fonts that should be used in Arabic books and leaflets for low vision patients. Methods: Arabic sentences were read by 100 normally sighted volunteers with and without simulated cataract. Subjects read two font types (Times New Roman and Courier) in three different sizes (N8, N10 and N12). The subjects were asked to read the sentences aloud. The reading speed was calculated as number of words read divided by the time taken, while reading rate was calculated as the number of words read correctly divided by the time taken. Results: There was an improvement in reading performance of normally sighted and simulated visually impaired subjects when the print size increased. There was no significant difference in reading performance between the two types of font used at small print size, however the reading rate improved as print size increased with Times New Roman. Conclusion: The results suggest that the use of N12 print in Times New Roman enhanced reading performance in normally sighted and simulated cataract subjects.     

粉针剂无菌分装模拟验证

目的:为确保粉针无菌分装生产整个过程对产品不产生污染,保证粉针生产药品质量,我们采取一系列验证试验.方法:我们采取无菌分装模拟验证,而且每年做一次.结果:通过此次验证,观察14天乳糖培养情况,我们可知试验乳糖合格率达到100%,染菌率0%.结论:此次验证对乳糖没有造成污染,保证了无菌分装,为粉针剂无菌分装提供了可靠的数据.     

Investigation of bone changes in microgravity during long and short duration space flight: comparison of techniques

BACKGROUND: Loss of bone mass is a continuing problem in long-term space flight. Although counter-measure programmes have been developed, effective assessment of these programmes is hampered by a lack of monitoring techniques that can be used in-flight. MATERIALS AND METHODS: Three techniques were used to evaluate changes in bone during two missions of 180 and 20 days to the MIR space station, involving three subjects. Dual energy X-ray absorptiometry (DXA) was used before and after flight to measure whole body and regional bone mineral density (BMD). Ultrasonic measurements of velocity (SOS) and broadband attenuation (BUA) of the calcaneus were measured during the 180 day mission and before and after the 20 day mission. Phase velocity of flexural waves in the tibia was also measured on the same days as the ultrasonic measurements of the calcaneus. RESULTS: DXA measurements demonstrated significant variation between different sites in the body for changes in BMD, with the greatest changes occurring in the lumbar spine and proximal femur. There was a trend for increasing phase velocity in the tibia during the 180 mission, but this was not significant. BUA and SOS measurements of the calcaneus showed consistent but divergent patterns of changes during the mission. CONCLUSION: Although in-flight measurements of bone using ultrasound or phase velocity may provide information on the kinetics of bone loss in space flight, the heterogeneity of response in the skeleton means that it is difficult to predict overall bone loss from measurements at one particular site.     

宫内节育器(Cu-IUD)体外释放Cu~(2+)以及含药Cu-IUD体外释放吲哚美辛的研究

目的:比较含Cu及含消炎药IUD释放Cu2+和吲哚美辛(IMC)的释放行为。方法:通过模拟人体宫腔内环境,采用火焰原子吸收光谱仪和UV-752分光光度仪测定TCu380A IUD、MLCu375 IUD和元宫型药Cu365IUD 300d内Cu2+和320d内IMC的释放行为。结果:3种Cu-IUDs的Cu2+都呈现了双相的释放行为:初始阶段的快速释放与随后的稳定缓慢释放。元宫型药Cu365IUD的Cu2+释放为零级过程,其内IMC的体外释放结果符合Weibull方程。结论:3种型号中,元宫型药Cu365IUD中Cu2+的释放最为稳定。依据IMC的体外释放特点,可以解释含药Cu-IUD防治置IUD副作用的功能。     

计算机仿真实验在机能学实验教学中的应用

计算机仿真实验是以虚拟实验动物为实验对象,利用计算机仿真实验软件系统来完成特定实验项目的一种实验教学形式。它是机能学活体动物实验教学的有益补充及延伸。其科学严谨的实验操作流程,丰富的实验项目和处理因素,高实验成功率及文字、语音、图像、动画等多媒体信息并举的实验教学模式,有助于当代大学生综合素质的提高。     

Conformational studies of a synthetic cyclic decapeptide fragment of rat transforming growth factor-α

The solution conformation of a synthetic cyclic decapeptide [with sequence mimicking the third disulfide loop of rat transforming growth factor-α (rTGF-α)] in deuterated dimethyl sulfoxide was studied by 2D NMR. The determination of solution structures was based on NOE interproton distances, using a combination of distance geometry and simulated annealing protocols. The convergence of the selected structures was evident from the small atomic pairwise root-mean-square deviation values among them. Good agreement was noted between the experimental and simulated NOESY spectra, thereby reflecting the accuracy of the calculated solution structures. Analysis of the structures indicates that the residues Tyr5 and Arg9 exhibit similar side chain orientation as that in the corresponding disulfide loop of human transforming growth factor-α.     

模拟舱中超氧化物供氧的医学观察

为研究人体正常活动状态在模拟舱环境之间气体交换的关系，探讨超氧化物在供氧系统中的作用，由６名１８～１９岁的健康男性青年在相对密闭的模拟舱内常压下，分别采用超氧化钾（ＫＯ２），超氧化钠（ＮａＯ２）进行试验。结果：单罐ＫＯ２的利用率为９２％～９６％，受试者平均氧耗量为４２４．３Ｌ／人·ｄ－１，能量值平均为１０２Ｗ／人，ＮａＯ２的利用率为７３％，平均氧耗量为４３９．８Ｌ／人·ｄ－１，能量值平均为１０５Ｗ／人，双罐ＫＯ２的利用率为９５％～９８％，平均氧耗量为４６４．０Ｌ人·ｄ－１，能量值平均为１１１Ｗ／人。这为进一步开展生命保障系统的试验研究提供了科学依据。     

The Role of a Computerised Case-based Testing Procedure in Practice Performance Assessment

Introduction: For postgraduate training of doctors there is a need for valid and reliable instruments to assess their daily performance. Various instruments have been suggested, some of which use incognito simulated patients (SPs). These methods are resource intensive. Computerised Case-based testing (CCT) is logistically simpler and may still predict performance well. The research question was to evaluate the predictive validity of CCT for performance.Methods: Seventeen rheumatologists were each visited by eight incognito SPs presenting various rheumatological complaints, and scoring the performance of the rheumatologists using a predefined checklist. From this checklist a panel of experts identified essential items. In addition the rheumatologists sat a CCT test containing 55 cases with a total of 121 items.Results: Negative correlations were found between the SP scores and the CCT scores. This was unexpected. Therefore, background variables on experience were used to compare both methods. The correlation between these and CCT were high and positive and with the SP scores high and negative. This pattern did not differ when using the essential items of the checklist. Reliabilities of the SP scores were markedly high.Discussion: Although CCT was not predictive of SP scores, it was related to working experience. There are good reasons to assume that although SP-scores were more authentic, they were less valid than CCT scores, mainly because they focussed more on thoroughness than on efficiency in data gathering. The results underpin the assumption that for valid performance assessment the most important issue is what information about the candidate is collected and now how authentic the method is.     

The structure and response properties of Golgi tendon organs in control and hypodynamia-hypokinesia rats

The Golgi tendon organs (GTOs) are encapsulated mechano-receptors that, in normal conditions, monitor via Ib afferent fibers the contractile force. A 14-day period of hypodynamia, absence of weight bearing and hypokinesia, and reduction of motor activity (HH) is known to induce changes in postural muscles such as the soleus. At present, there is no data available regarding the Ib afferent feedback in normal rats (CONT group) and in rats after a hypodynamia-hypokinesia (HH group) period. Consequently, the aim of our study was to determine the HH effects on the morphological (histochemistry on gross morphology) and electrophysiological properties of the GTOs in rat soleus muscle. In the histological study, nine CONT and nineteen HH GTOs of the soleus muscle were identified. The results demonstrated that HH GTOs were morphologically similar to the CONT GTOs. Regarding the electrophysiological study, a L2-L6 laminectomy was performed under deep anesthesia (sodium pentobarbital, 60 mg kg(-1)). Responses in single Ib fibers from the L5 dorsal root to the isometric twitch and tetanic fused contractions of "in-series" motor units (MUs) were recorded. Twenty-three and twenty-eight GTO/MU pairs were studied in the CONT and HH groups, respectively. In the HH group, the Ib afferent response exhibited a decrease in dynamic peak for the high stimulation frequencies and an increase in static sensitivity for all stimulation frequencies. Our results suggest that after an HH period, the GTOs continue to fulfil their mechano-sensory function to signal the contractile force but with a higher static sensitivity.     

Neuromuscular adaptations to spaceflight are specific to postural muscles

The effects of microgravity were determined in muscles of differing function and myofiber-type composition. Rats were assigned either to a 10-day spaceflight mission or to ground-based control conditions. Following the experimental period, hindlimb muscles were obtained from both groups. Cytofluorescent techniques were used to examine neuromuscular junctions (NMJs) from both slow- and fast-twitch fibers. Histochemical procedures were employed to assess myofiber profiles (size and type). Results indicate that microgravity did not alter NMJ structure or myofiber profile in the tibialis anterior, a predominantly fast-twitch, nonpostural muscle. Similarly, the NMJs and myofibers of deep regions of the gastrocnemius, a locomotor muscle possessing a mixed fiber population, were unaffected by spaceflight. In contrast, both myofibers and NMJs of the soleus-a postural muscle-demonstrated significant (P < 0.05) plasticity following exposure to spaceflight. Moreover, NMJs of both fast- and slow-twitch myofibers displayed similar remodeling in that muscle. Our findings suggest that the deleterious effects of microgravity are most apparent among postural muscles, and are manifested both in myofibers and their synapses.