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1.
In order to define more accurately normal dimensions and form of the lacrimal point as well as peculiarities in the structure of the vertical part of the lacrimal canaliculus, 315 practically healthy persons (630 eyes) at the age of 18-60 years have been examined. The procedure has been performed by means of the slit lamp (shchl-1) . The lacrimal point has been found to have a round (36.1%) and an oval (63.9%) form. Transition of the lacrimal point into the vertical part of the lacrimal canaliculus in 83.5% of the observations is "fannel"-shaped with a maximal narrowing at the depth of 0.4-0.5 mm, and in 16.5%-- well"-shaped (without any narrowing). The normal diameter of the lacrimal point is 0.2-0.6 mm (the arithmetic mean-- 0.35 mm). When the diameter of the lacrimal point is less than 0.2 mm (at least in one of its sections), the lacrimation function correspondingly deteriorates, indices of the coloured nasolacrimal test become decreased or negative. 相似文献
2.
The three-dimensional organization of the tear film, which is produced and drained by the different structures of the ocular adnexa, is essential for maintainance and protection of the ocular surface. This is facilitated by a class of large, highly glycosylated, hydrophilic glycoproteins, the mucins, which are usually expressed in association with a class of peptides having a well-defined, structurally conserved trefoil domain, the mammalian trefoil factor family (TFF) peptides. In this review, the latest information regarding mucin and TFF peptide function and regulation in the human lacrimal system, the tear film and the ocular surface is summarized with regard to mucous epithelia integrity, rheological and antimicrobial properties of the tear film and tear outflow, age-related changes and certain disease states such as dry eye, dacryostenosis and dacryolith formation. 相似文献
3.
Hemibrycon
sanjuanensis, new species, is described from the upper San Juan River drainage, Pacific versant, Colombia. It is distinguished from Hemibrycon
boquiae, Hemibrycon
brevispini, Hemibrycon
cairoense, Hemibrycon
colombianus, Hemibrycon
mikrostiktos, Hemibrycon
metae, Hemibrycon
palomae, Hemibrycon
rafaelense and Hemibrycon
tridens by the presence of a circular or oblong humeral spot that is located two scales posterior to the opercle (vs. 3–4 scales in Hemibrycon
palomae, Hemibrycon
rafaelense, Hemibrycon
brevispini and Hemibrycon
cairoense, and 0–1 scales, in Hemibrycon
metae and Hemibrycon
boquiae). It further differs from Hemibrycon
colombianus in having a round or oblong humeral spot (vs. rectangular). It differs from Hemibrycon
beni, Hemibrycon
dariensis, Hemibrycon
divisorensis, Hemibrycon
helleri, Hemibrycon
huambonicus, Hemibrycon
inambari, Hemibrycon
jabonero, Hemibrycon
jelskii, Hemibrycon
mikrostiktos, Hemibrycon
polyodon, Hemibrycon
quindos, Hemibrycon
raqueliae, Hemibrycon
santamartae, Hemibrycon
surinamensis, Hemibrycon
taeniurus, Hemibrycon
tridens, and Hemibrycon
yacopiae in having melanophores on the posterior margins of the scales along the sides of body (vs. lacking melanophores on margins of scales along entire length of the sides of body). The new species differs from all congeners mentioned above in having, among other features, six teeth in the outer premaxillary row arranged in a straight line (vs. five or fewer teeth not arranged in straight line except Hemibrycon
cairoense with two to six teeth in the outer premaxillary row). 相似文献
6.
Current clinically used chemotherapeutic platinum drugs can trigger severe toxic effects. To develop a model system for the evaluation of the therapeutic efficacy and the toxic effects of new platinum agents, we have synthesized a new compound N-[(2S,3R,4R,5R)-2,3,4,5,6-pentahydroxylhex-1-yl]-L-hydroxyproline dichloroplatinum(ii) (PHDP), compared its in vitro anti-proliferation activity, in vivo anti-tumor activity and safety to those of oxaliplatin, and correlated all these biological actions with the platinum occurring in the spleen, kidney, heart, brain, blood, tumor tissue, urine and faeces of the treated mice. We explored the atomic absorption based determinations of the platinum which occurred in the spleen, kidney, heart, brain, blood, tumor tissue, urine and faeces and constitute a model system that can be generally used in the investigation of the novel platinum agents. 相似文献
7.
The covalent addition of methylgroups to cytosine has become the most intensively researched epigenetic DNA marker. The vast majority of technologies used for DNA methylation analysis rely on a chemical reaction, the so-called ‘bisulfite treatment’, which introduces methylation-dependent sequence changes through selective chemical conversion of non-methylated cytosine to uracil. After treatment, all non-methylated cytosine bases are converted to uracil but all methylated cytosine bases remain cytosine. These methylation dependent C-to-T changes can subsequently be studied using conventional DNA analysis technologies. The bisulfite conversion protocol is susceptible to processing errors, and small deviation from the protocol can result in failure of the treatment. Several attempts have been made to simplify the procedure and increase its robustness. Although significant achievements in this area have been made, bisulfite treatment remains the main source of process variability in the analysis of DNA methylation. This variability in particular impairs assays, which strive for the quantitative assessment of DNA methylation. Here we present basic mathematical considerations, which should be taken into account when analyzing DNA methylation. We also introduce a PCR-based assay, which allows ab initio assessment of the DNA quality after bisulfite treatment and can help to prevent inaccurate quantitative measurement resulting from poor bisulfite treatment. 相似文献
9.
A new species of the sisorid catfish genus Exostoma Blyth,1860 was collected from two hill-stream tributaries of the Nujiang (Salween River) drainage in Gaoligong Mountain,south-western Yunnan Province,China from 2003 to 2006 and from two tributaries of the Salween River in Cangyuan County,Lingcang Prefecture,Yunnan Province,China (in 2007) and in Yongde County,Lingcang Prefecture,Yunnan Province,China (in 2015).Exostoma gaoligongense sp.nov.is the 10th species of the genus and is most similar to E.vinciguerrae in morphology but can be distinguished by pelvic fin reaching anus vs.not reaching;maxillary barbels just reaching or slightly surpassing pectoral-fin origin vs.surpassing pectoral-fin origin or even reaching posterior end of gill membrane;abdominal vertebrae 23-25 vs.25-27;length of dorsal fin/dorsal to adipose distance 90.3%-287.0% vs.59.2-85.7.A key to Exostoma spp.is provided. 相似文献
11.
GJB2 (Gap Junction protein beta type 2; Connexin 26, CX26) is known for its contribution to nonsyndromic recessive deafness (NSRD). One particular mutation, 35delG, a deletion of one guanine from a stretch of six leading to a frame shift early in the gene, has a high prevalence in populations from European descent. 35delG testing therefore has become a standard test in genetic diagnostic laboratories. Most of the currently available methods for the detection of 35delG are relatively time consuming, and not suited for high-throughput diagnostic testing. Within this paper we present a real-time PCR genotyping assay based on melting curve analysis, requiring only a single preparation step before the actual analysis. The assay was optimized on a panel of 48 samples with known 35delG genotypes and subsequently tested using a large Belgian population (N = 460) with unknown 35delG status. For the latter set of samples, real-time PCR results were validated with SNAPShot, an assay used in our laboratory for diagnostic purposes. The real-time PCR genotyping method has proven to be highly reliable, rapid, cost-effective, and suitable for high-throughput screening. We believe that this genetic test for 35delG will find widespread applications in the DNA diagnostic field. 相似文献
12.
In recent decades, much of the progress observed in the study of beaches to aid policy has focused on producing sound substantive and/or contextual knowledge. However, attention has not usually been paid to the procedural manner in which it has been produced. Guided by an open learning process, this study aims to develop and present an expanded reviewed assessment of the Catalan coast operationalized by means of the Double-Looped Beach Quality Index (DL-BQI). Such openness helps us to understand which narratives of beach management in Catalonia are operating (and which are excluded), the extent to which they are unfolding, and the capacity of the DL-BQI to provide information for policymaking. Data collection enabled assessment of 96 representative beaches on the Catalan coast, that may find correspondence with other geographic locations. Both the instrument used for the assessment – the DL-BQI – and its results were co-evaluated at a multi-stakeholder meeting. In general, beaches have mainly been conditioned to supply elements for tourism and leisure. Different pressures have arisen from the orientation towards such activities, usually according to beach type, most of them negatively impacting the ecological assets and natural heritage of beaches. The economic growth narrative, albeit predominant, was shown to be deficient for tackling complex coastal problems, i.e. intensifying ecological deterioration. Alternatively, the study shows the importance for regional coastal policy of considering the value of beaches as natural systems, as advocated, to a greater or lesser extent, by the narratives of sustainability, environmental protection and integrated coastal zone management. This research innovates on considering substantive, contextual and procedural dimensions of knowledge quality for the governance of beach systems, by relating dimensions, narratives and outcomes. 相似文献
13.
The successful development of a therapeutic agent targeting treatment of dry eye syndrome necessitates the demonstration of drug efficacy for both sign and symptom endpoints. As numerous therapeutic strategies incorporate a secretagogue function into their overall mechanism of action, the quantitative assessment of tear production serves as a logical endpoint to anchor “sign” efficacy. Although several methods including the Schirmer, the phenol red thread and tear clearance tests exist, their utility in clinical evaluations of novel therapeutics is unclear. The purpose of this review is to summarize findings and conclusions describing the performance of each of these tests so as to gain insight into which, if any, is most applicable for use in discovering new dry eye therapeutics. 相似文献
15.
One argument that is frequently invoked against the technological enhancement of human functioning is that it is morally suspect, or even wrong, to take an easy shortcut. Some things that usually take effort, endurance or struggle can come easily with the use of an enhancer. This paper analyses the various arguments that circle round the idea that enhancement of human functioning is problematic because of the 'easy shortcut' that it offers. It discusses the concern that quick fixes lead to corrosion of character and the idea that suffering, pain, hard work and effort are essential for real and worthy achievements, and argues that these views are largely mistaken. Next, the paper argues that the core worry about taking an easy shortcut is that it makes us lose sight of the complexities of our means and ends; in other words, the argument warns against reducing the richness of human activities. A vocabulary of 'practices', 'internal goods' and 'focal engagement' will be used to articulate this argument further. The conclusion is that the easy shortcut argument has no general validity as an argument against enhancement 'as such'. The paper urges us, however, to evaluate enhancement technologies not only in terms of their efficiency in reaching certain goals but also in terms of their contribution to intrinsically worthwhile human activities. It can point out some of the caveats, as well as the opportunities, of the use of enhancement technologies. 相似文献
16.
热河生物群的翼龙都发现于义县组和九佛堂组。金刚山层位于义县组上部,已经报道的翼龙包括最早发现的两件翼龙胚胎,两件古翼手龙超科的标本,以及一件存疑的金刚山义县翼龙。对这一层位发现的一件前肢标本进行了描述,并确定其属于无齿翼龙超科。对现存于本溪地质博物馆的金刚山义县翼龙的正型标本进行了观察,并修订其鉴定特征。无齿翼龙超科成员具有独有的特征组合为:牙齿垂直于咬合面,呈三角形且唇舌向扁,前两对更长更细;第二翼指骨长度约为第一翼指骨的93%。在热河生物群中,古翼手龙超科的标本主要发现于义县组,而古神翼龙超科主要发现于九佛堂组。包括这件新标本和金刚山义县翼龙在内的无齿翼龙超科在九佛堂组发现的略多于义县组,这与之前认为的翼龙分布情况不同。 相似文献
17.
Stream discharge and fine suspended sediment load were determined for the upper Kuparuk River, a clear-water tundra stream
and tributary of the main Kuparuk River of the North Slope of Alaska. From 75 observations over 3 years we found a range of
flows of 0.3 to 28.3 m 3 sec −1 and a range of sediment loads of 0.4 to 35 mg liter −1. Specific water yields of 15.7, 29.7 and 33.2 cm and summer specific sediment yields of 0.5, 1.1 and 3.5 metric tons km −2 were estimated for the period 20 May through freeze-up in 1978, 1979 and 1980, respectively. The fine suspended sediment
concentrations and yields for the upper Kuparuk River were less than those in many temperate streams but similar to those
reported for small rivers draining the taiga of the Mackenzie Valley lowlands in subarctic Canada. 相似文献
18.
The period prior to anthesis determines to a great extent the yield in wheat by modifying the number of fertile florets and hence the number of grains per spike. For an easy and accurate identification of this period to researchers and cereal growers a simple numerical scale of wheat spike development is proposed. It includes 20 distinct stages, starting from the apex transition stage and ending just prior to heading, with the stages being separated by similar‐sized steps in thermal time to produce a continuous scale. The scale describes the whole process of wheat apical development and is convenient (e.g. uses easily detectable characters without great magnification, such as the development of awns, lemmas and glumes) and precise (e.g. uses combination of more stable characters, such as pistil and stamen development as well as the sequence of floret initiation, in order to accurately assess the development of the spike). The proposed scale was used to describe the development of the durum wheat cultivar “Mexicali 81” during two seasons. The meteorological conditions during the different cultivation seasons affected the onset and the duration of the spike developmental phases. Additionally, a variation was observed concerning the synchronisation between spike morphogenesis and plant external developmental phases (e.g. tillering, jointing and boot). The advantages of the new scale with respect to the already existing ones are discussed. 相似文献
19.
A new species of the cyprinid genus Placocheilus Wu 1977, is described from the Dulong River drainage (in the upper reach of the Irrawaddy River), northwestern Yunnan Province (China). Placocheilus dulongensis sp. nov. can be distinguished from the other three congeners, namely P. caudofasciatus, P. robustus and P. cryptonemus, by the following combination of characters: no semicircular black mark on the middle of each caudal fin lobe; no blackish band across the dorsal fin; one pair of rostral barbels and one pair of maxillary barbels; 39-40 perforated lateral line scales. Osteological characters, such as the shape of the second infraorbital, preoperculum, and the vertical plate of the urohyal were observed in a cleared and stained skeletal specimen. A simplified key to the genus Placocheilus is provided based on the comparisons among the four species. 相似文献
20.
BackgroundThe Great East Japan Earthquake of March 11, 2001 left around 20,000 dead or missing. Previous studies showed that rescue workers, as well as survivors, of disasters are at high risk for posttraumatic stress disorder (PTSD). This study examined the predictive usefulness of the Peritraumatic Distress Inventory (PDI) among rescue workers of Disaster Medical Assistance Teams (DMATs) deployed during the acute disaster phase of the Great East Japan Earthquake. Methodology/Principal FindingsIn this prospective observational study, the DMAT members recruited were assessed 1 month after the earthquake on the PDI and 4 months after the earthquake on the Impact of Event Scale-Revised to determine PTSD symptoms. The predictive value of the PDI at initial assessment for PTSD symptoms at the follow-up assessment was examined by univariate and multiple linear regression analysis. Of the 254 rescue workers who participated in the initial assessment, 173 completed the follow-up assessment. Univariate regression analysis revealed that PDI total score and most individual item scores predicted PTSD symptoms. In particular, high predictive values were seen for peritraumatic emotional distress such as losing control of emotions and being ashamed of emotional reactions. In multiple linear regression analysis, PDI total score was an independent predictor for PTSD symptoms after adjusting for covariates. As for covariates specifically, watching earthquake television news reports for more than 4 hours per day predicted PTSD symptoms. Conclusions/SignificanceThe PDI predicted PTSD symptoms in rescue workers after the Great East Japan Earthquake. Peritraumatic emotional distress appears to be an important factor to screen for individuals at risk for developing PTSD among medical rescue workers. In addition, watching television for extended period of time might require attention at a time of crisis. 相似文献
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