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1.
Because of fears that Polaroid colour prints produced with a non-mydriatic fundus camera may not detect important sight threatening lesions in diabetes a study was conducted comparing retinal images obtained on Polaroid prints taken in “field” conditions with those on 35 mm transparencies and fluorescein angiograms. Almost one in five (22/127) Polaroid prints could not be assessed owing to poor quality compared with 3 (2.4%) 35 mm transparencies and 2 (1.6%) fluorescein angiograms. The pick up rate of microaneurysms, haemorrhages, and hard and soft (cotton wool spots) exudates was equivalent for Polaroid prints and 35 mm transparencies of equivalent quality. In two cases with disc new vessels, however, these were not seen on the Polaroid prints.The widespread use of Polaroid colour prints obtained with a non-mydriatic camera without the necessary operative and interpretive skills further limits the usefulness of the technique.  相似文献   

2.
A simple method of photoduplication of gel electrophoresis, visualized with fluorescent reagents, is described. The procedure is convenient and rapid and requires no camera or expensive equipment. Using electrophoresis duplicating paper (Kodak), positive prints suitable for documentation or publication may be obtained. With usual photographic paper, negative prints may be obtained, allowing reliable measurement by scanning. The technique may be applied to protein or nucleic acid electrophoresis.  相似文献   

3.
The removal of extraneous biological materials from vertebrate ichnological specimens may be necessary if they have been exposed to subaerial processes in the field for long periods of time. It is not uncommon for fossil track specimens to be found nearly completely covered with lichen colonies, especially those recovered from alpine areas. This paper describes a technique using a sodium hypochlorite solution (bleach) to remove lichen from a track surface containing numerous avian prints and small theropod prints with skin impressions.  相似文献   

4.
We documented trackways of free-living Crocodylus acutus on beaches at the mouths of Tamarindo and Ventanas estuaries, Costa Rica. Our crocodiles had estimated total lengths of 1–3 meters or more. Manus prints have five digits, with digits I–III bearing claw marks. Pes prints have four digits, with claw marks on digits I–III. The pes is plantigrade. Claws generally dig into the substrate. Apart from claw marks, digit I and the heel of the pes are usually the most deeply impressed parts of footprints. Trackways are wide-gauge. Pes prints are usually positioned just behind ipsilateral manus prints of the same set and may overlap them. Manus and pes prints angle slightly outward with respect to the crocodile's direction of movement. Claw-bearing digits of both the manus and pes may create curved, concave-toward-the-midline drag marks as the autopodium is protracted. The tail mark varies in depth and clarity, and in shape from nearly linear to markedly sinuous. Sometimes the tail mark hugs the trackway midline, but sometimes it is closer to, or even cuts across, prints of one side. American crocodile footprints and trackways are similar to those observed in other extant crocodylian species, indicating substantial trackway conservatism across the group.  相似文献   

5.
赫哲族掌指纹特征研究   总被引:9,自引:5,他引:4  
本文对166名健康赫哲族人的掌指纹进行了研究,其中男性86名,女性80名。本文列出了58个赫哲族掌指纹参数,将其中52个掌指纹特征输入电子计算机,进行了相关及主成份分析。并且,将赫哲族的掌指纹特征与汉族的掌指纹特征进行了比较。 结果表明:赫哲族的掌指纹特征是与汉族相似的,并且有自己的特征;双手同名指的相关系数大于非同名指,单手相邻指的相关系数大于相隔指;在有关掌指纹特征的研究中,指纹的重要性大于掌纹。  相似文献   

6.
The present study was aimed at evaluating suitability of tissue prints for immunocytochemical evaluation of mammary cancer cells. The prints, originating from 30 cases of mammary cancer were studied using immunocytochemical reactions with monoclonal antibodies against estrogen and progesterone receptors, metallothionein (MT), P-glycoprotein and cytokeratins (clone LP34). Expression of individual antigens was assessed using the scale in which intensity of the colour reaction and percentage of positive cells were taken into account. The obtained results did not differ qualitatively or quantitatively from those obtained in paraffin sections. The studies have shown that tissue prints can be used for reliable immunocytochemical evaluation of expression of various proteins in mammary cancer cells.  相似文献   

7.
Kevin Padian 《Ichnos》2013,20(2-4):115-126
The tracks ascribed to pterosaurs from the Late Jurassic limestones at Crayssac, France, must be pterosaurian because the manus prints are so far outside those of the pes, the pes print is four times longer than wide, and the manus prints appear to preserve distinct traces of a posteromedially directed wing-finger. These tracks are different in important ways from previously described Pteraichnus trackways, which have been variably considered pterosaurian, crocodilian, or indeterminate. No Pteraichnus (sensu stricto: those not from Crayssac) tracks have diagnostic features of pterosaurs and in none can a complete phalangeal or digital formula be reconstructed; however, all published Pteraichnidae tracks fulfill the criteria of poor preservation, and some have some diagnostic features of crocodile tracks. Reconstructions of pterosaurs walking in pteraichnid tracks do not fit those tracks well, but crocodiles do. In contrast, the Crayssac tracks demonstrate the erect stance and parasagittal gait previously reconstructed for pterosaurs. They also demonstrate that the footfall pattern was not as in typical reptiles (LH-RF-RH-LF), but that the manus must have been raised before the next forward step of the ipselateral foot (LH-LF-RH-RF), suggesting that the quadrupedal pattern was secondary. The metatarsus in pterosaurs was set low at the beginning of a stride, as it is in crocodilians and basal dinosaurs. The diagnosis of the Ichnofamily Pteraichnidae comprises features of possible crocodilian trackmakers, but not of possible pterosaurian trackmakers. Trackways considered for attribution to pterosaurs should show (1) manus prints up to three interpedal widths from midline of body, and always lateral to pes prints, (2) pes prints four times longer than wide at the metatarso-phalangeal joint, and (3) penultimate phalanges longest among those of the pes.  相似文献   

8.
9.
Latent print examiners use their expertise to determine whether the information present in a comparison of two fingerprints (or palmprints) is sufficient to conclude that the prints were from the same source (individualization). When fingerprint evidence is presented in court, it is the examiner''s determination—not an objective metric—that is presented. This study was designed to ascertain the factors that explain examiners'' determinations of sufficiency for individualization. Volunteer latent print examiners (n = 170) were each assigned 22 pairs of latent and exemplar prints for examination, and annotated features, correspondence of features, and clarity. The 320 image pairs were selected specifically to control clarity and quantity of features. The predominant factor differentiating annotations associated with individualization and inconclusive determinations is the count of corresponding minutiae; other factors such as clarity provided minimal additional discriminative value. Examiners'' counts of corresponding minutiae were strongly associated with their own determinations; however, due to substantial variation of both annotations and determinations among examiners, one examiner''s annotation and determination on a given comparison is a relatively weak predictor of whether another examiner would individualize. The extensive variability in annotations also means that we must treat any individual examiner''s minutia counts as interpretations of the (unknowable) information content of the prints: saying “the prints had N corresponding minutiae marked” is not the same as “the prints had N corresponding minutiae.” More consistency in annotations, which could be achieved through standardization and training, should lead to process improvements and provide greater transparency in casework.  相似文献   

10.
Russell H. Tuttle 《Ichnos》2013,20(3-4):158-165
In 1978 and 1979 at Laetoli, Northern, Tanzania, Mary D. Leakey and assistants excavated the most compelling evidence for the existence of bipedalism in Pliocene (3.5 Ma) hominids. They have stimulated controversy over the extent to which the three individuals had feet and gaits that are like those of humans versus having ape-like features and gaits. A short trail of bipedal tracks discovered in 1977 at Laetoli site A are probably not those of a hominid and more closely resemble the prints of bears. One of the original researchers on the Laetoli prints claimed that she could identify individual modern humans from their footprints, partial footprints and shoe prints because each individual has distinctive foot morphology on a par with the individuality of fingerprints. Courts of law should not have allowed her unproven (and now discredited) method to be used forensically prior to thorough review by scientific peers.  相似文献   

11.
Abstract: If individuals can be identified from patterns in their footprints, noninvasive survey methods can be used to estimate abundance. Track plates capture fine detail in the footprints of fishers (Martes pennanti), recording rows of dots corresponding to tiny papillae on the animal's metacarpal pad. We show that the pattern of these dots can be used to identify individual fishers, similar to human fingerprints. A probabilistic model of uniqueness based on variation in spacing between 1,400 pairs of dots that we measured in prints of 14 different fisher feet suggests the probability of encountering a similar pattern in the print of a different foot by chance alone is ≤ 0.35n, where n = the number of dot pairs examined. This predicts a 0.00003 probability that a match made using 10 pairs of dots is false. Dot spacing from footprints made by the same foot was remarkably consistent (sN = 0.02 mm, n = 24 dot pairs). Combined, these results suggest dot patterns in fisher footprints were unique to individuals and were consistently reproduced on track plates. Empirical tests of matching accuracy were best with good-quality prints, highlighting the need for experience judging when prints are usable. We applied print matching to fisher detections collected on track plates deployed at 500-m intervals along 10 3.5-km transects in the Adirondack region of New York, USA. Of 62 fisher detections, 85% had ≥ 1 footprint of suitable quality to compare with other high-quality prints. We found that most detections from a transect were from the same individual fisher suggesting nonindependence of detections. Thus, data from traditional track-plate deployments over small time periods cannot be used as a measure of abundance, but new study designs using print matching could obtain robust noninvasive, mark—recapture density estimates.  相似文献   

12.
中国人唇纹研究初报   总被引:1,自引:0,他引:1  
梁光  邝国壁 《人类学学报》1990,9(3):212-216
本文研究了1403名中国人的唇纹及唇纹的稳定性,统计分析了六种唇纹型的出现率。与日本人的资料作了比较和讨论。  相似文献   

13.
A procedure was established for easy and convenient detection of plant DNA, plant RNA and viral RNA from plant tissue prints on FTA® (Flinders Technology Associates, Moscoso et al., 2005) PlantSaver Cards, while avoiding the cross-contamination that commonly occurs with prints from plant tissues. Detection was successful by adding 2 mm discs of the prints directly to (RT)-PCR reactions. DNA was detected in leaves from tobacco, tomato and grapes, and in fruit of tomato and grape. Rubisco and malate dehydro-genase RNA were detected in tomato fruit and leaf, tobacco leaf and grape leaf. RNA from Pepino mosaic virus was detected in tomato leaf and fruit and from Rupestis stem pitting associated virus in grape leaf. Detection was still possible from the tissue prints on FTA® Cards after storage for many months at room temperature, making this a procedure suitable for sample collection and storage off site, prior to further processing in the laboratory.  相似文献   

14.
Tissue printing onto membranes such as nitrocellulose is a technique employed to study the localization of proteins, nucleic acids, and soluble metabolites from freshly cut tissue slices. We probed tissue prints of young and mature celery (Apium graveolens) petioles with antibodies raised against two proteins, spinach ribulose-1,5-bisphosphate carboxylase and tomato fruit catalase. The purposes of this study were to determine if these proteins are developmentally regulated and to determine if the patterns and intensities of cross-reactivity of antibodies on tissue blots corresponded only to the presence of specific epitopes or was related to the amount of protein present in any given area on the tissue prints. Different and distinct cross-reactivity patterns were observed with each of the two antibodies used. Tissue prints from young and mature tissues also showed differences in antibody cross-reactivity. Comparison of Coomassie blue staining patterns with antibody reactivity patterns showed that there is little relationship between tissue protein concentration and antibody reactivity.  相似文献   

15.
A fundamental event in abscission is the breakdown of cell wall material in a discrete zone of cells known as the separation layer. Three dimensional images produced by viewing tissue prints of abscission zones on nitrocellulose (NC) membranes with incident illumination showed changes in the tissue integrity taking place in the separation layer as the process of abscission proceeded. The cell softening which occurs due to the dissolution of the cell wall appeared in the tissue prints as a diffuse line at the anatomical transition between the pulvinus and petiole and was easily observed on NC tissue prints of either longitudinal or serial cross-sections through abscission zones. In bean leaf abscission the dissolution of cell walls has been correlated with the appearance of a form of cellulase with an isoelectric point of pH 9.5. Antibodies specific for this enzyme were used to study the localization of 9.5 cellulase in the distal abscission zone of Phaseolus vulgaris L., cv Red Kidney after tissue printing on NC. It was found that 9.5 cellulase was localized in the separation layer but also occurred in the vascular tissue of the adjacent pulvinus. No antibody binding was observed in nonabscising tissue or preimmune controls. These results confirm previous biochemical studies and demonstrate that immunostaining of nitrocellulose tissue prints is a fast and reliable method to localize proteins or enzymes in plant tissue.  相似文献   

16.
Ten new Dinosaur foot prints fields have been discovered in Middle Jurassic red beds of Central High Atlas (Morocco). Ovoid prints (Sauropod) are there more common than tridactyle (Theropod). The trace fossils appear at two distinct levels of the red beds which have been previously rattached to Cretaceous.  相似文献   

17.
Reports of human footprints from North American archaeological sites are summarized and described. Although some human footprints have been claimed to be of Pleistocene and earlier ages, the earliest authenticated prints in America north of Mexico, as distinct from Central or South America, date to the Holocene. The earliest of these prints is at least 5,070 years old, and the youngest are late prehistoric period, only about 400 years old. Footprint sites are reported in the U.S. Southeast, Southwest, and California. Activities indicated by ancient North American human footprints include the mundane, such as daily tasks in a riparian zone and domestic behaviors inside a habitation. Footprints were also left by prehistoric peoples undertaking more esoteric activities deep in cave interiors, including exploration, mineral extraction, and ritual.  相似文献   

18.
A method for protein staining using copper phthalocyanine 3,4',4',4'-tetrasulfonic acid tetrasodium salt is described. The procedure is applicable to protein blots and tissue prints, as well as to polyacrylamide and agarose gels. It is also simple, involving only application of the stain and rinsing. For protein blots and tissue prints the staining is rapid, taking less than 1 min to completion, and more sensitive than any previously described dye-based nonspecific protein staining system. The staining is easily reversible, requiring only a change in pH to remove the dye.  相似文献   

19.
David L. Roberts 《Ichnos》2013,20(3-4):190-207
Two Late Pleistocene hominid footprint sites are known in South Africa, one on the west coast (Langebaan) and the other on the southeast coast (Nahoon). Both trackways occur in calcareous eolianites and are dated to the Last Interglacial (~120 ka). The chief objective is to infer anatomical features of these early anatomically modern hominid footprint makers, about which little is known. At Nahoon, trackways of at least five species of vertebrates, including three hominid footprints, are preserved as casts. One footprint preserves excellent detail, appearing in all respects to be modern, but possibly with a deformity of the small toe. The impressions are shallow and suggest slight build. The stature of the footprint maker, as estimated from foot length (19.2 cm), is ~127 cm, considerably less than modern adult Khoi-San and was probably made by a juvenile. The step length is short relative to foot length, a consequence of walking uphill on a yielding substrate. The Langebaan trackway (preserved as natural impressions) comprises two intact prints and remnants of a third. Pronounced push up mounds flank the prints and preservation of toe impressions is poor. The foot length is 22.8 cm, indicating a stature of ~1.57 m. This falls within the range of modern adult Khoi-San, lending some support to the notion that Middle Stone Age people were of small stature. The depth of the prints and clumsy progression are suggestive of heavy build.  相似文献   

20.
Kinh is the largest population in Vietnam. It belongs to Mon-Khmer linguistically, but there is no last word for its origin. There are three hypotheses for the homeland of Kinh. The formation of Kinh population is also hypothesized to have occurred by one of two different modes. One is demic diffusion of Mon-Khmer, the other is Daic population assimilated by Mon-Khmer. Population studies such as dermatoglyphics can be used to determine the relevant mode. Fingerprints, palm prints, and sole prints of 135 individuals from Kinh populations all over Vietnam were collected in this project. Principle component analysis and dendrogram analysis were done based on the dermatoglyphic data of populations from south China and Vietnam. Kinh Vietnamese was found to be quite close to Deang and Blang, which belong to the Mon-Khmer group, but are not closely related to the Daic populations. This study supports the demic diffusion mode of the formation of the Kinh population. The interaction with the Daic population was never a significant course in the formation of Kinh.  相似文献   

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