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At least 55 records · Page 3Linked to original sources
PubMed1981

[Variable extensor apparatus of the small toe. Opposing muscle groups in competition for extensor function of the fifth involutional metacarpal ray of the lower extremity].

In 200 human feet 37 differently formed extensor apparatus of the fifth toe were found. This great variability is obviously caused by several independent phylogenetic processes related with the acquisition of the upright gait. In primitive tetrapods three extensor muscles exist for the toes, whereas in mammals two of these muscles are in a rivalling but not vicarious relationship: While the long extensor muscles (M. extensor digitorum longus) remain in all trinomial toes, the fibular extensor muscles (Mm. peronaei digitorum) are laterally displaced by the short extensor muscles (M. extensor digitorum brevis). Although in man the fibular extensor muscles are largely suppressed, the short extensor muscles hardly often reach the fifth toe because this involuting toe is only of limited motor importance with regard to the entire function of the human foot. The ontogenetic involution of the fibular extensor muscles - which in the human embryo are regularly developed as M. peronaeus digiti IV and M. peronaeus digiti V - usually remains at an intermediate stage, i.e. a tendon of the M. peronaeus brevis branches off towards the dorsum pedis. In the anthropoids this involution is associated with the evolution and acquisition of the M. peronaeus III. To obtain strong effects for pronation and dorsiflexion necessary for the upright gait the M. peronaeus III inserts at the stable metatarsus instead of the mobile fifth toe by which an earlier phylogenetic stage is achieved. In the metatarsus the peronaeus tertius muscle inserts in different positions with regard to the remnants of the fibular extensor muscles. In this paper the two processes - both involution of the peronaei digitorum muscles and evolution of the peronaeus tertius muscle - are illustrated by several intermediate links found in dissected feet.

Biological Evolution↗
PubMed2000

Molineus cati n. sp. (Nematoda, Trichostrongylina, Molineoidea), a parasite of feral cats, Felis catus Linnaeus, 1758 in South Africa.

A new species of the genus Molineus Cameron, 1923 was recovered from feral cats, Felis catus Linnaeus, 1758, in Mpumalanga Province, South Africa. Because of a caudal bursa with rays of the 2-1-2 type, but with the extremities of rays 4 nearer those of rays 3 than those of rays 5, the new species is closely related to seven Neotropical Molineus spp., four parasitic in Primates, two parasitic in Mustelidae and one a parasite of Procyonidae. Amongst these species, only Molineus barbaris Cameron, 1936, a parasite of Tayra barbara (Mustelidae) from Trinidad and Molineus vexillarius (Dunn, 1961), a parasite of Tamarinus nigricollis (Primates) from Peru have rays 4 longer than two-thirds the length of rays 3, like the new species. However, the new species is differentiated from the other two in that rays 9 arise at the level of the bifurcation of the dorsal ray and not after the division as is the case with M. barbaris and M. vexillarius.

Animals↗
PubMed1994

[Clinical applications of synchrotron radiation X-ray].

Synchrotron Radiation X-ray (SR X-ray) is an extremely strong X-ray source with a photon number more than 10(4) compared with that of the current X-ray tube. X-rays obtained by monochromatizing SR X-ray have been applied to new techniques for medical diagnosis. Several studies are now being conducted at the beam site for medical use at the Accumulation Ring of the High Energy Physics Research Institute, Tsukuba. Applications being studied include (1) energy subtraction coronary angiography. (2) microdetection of metas in samples excised from subjects. (3) monochromatic X-ray computed tomography and so on. Energy subtraction coronary angiography might have a safety advantage over the current selective coronary angiography. Microdetection of mandatory metals and poisonous heavy metals in in vivo samples contributes to the development of pathologic knowledge and clinical treatment of cancer and heavy metal toxications. Monochromatic X-ray CT is expected to detect diseases in the early stage due to increased accuracy in CT values.

Energy-Generating Resources↗
PubMed1979

Feulgen type staining with Hoffmann's violet-SO2 under exposure to UV rays.

The paper contains an account of the use of Hoffmann's violet-SO2 under exposure to UV rays during staining acid-hydrolysed DNA of mammalian tissue nuclei. Preparations stained with Hoffmann's violet-SO2 without exposure to UV rays reveal extremely pale violet nuclei but when stained under the influence of UV rays show a considerably faster reaction resulting in a very much deeper staining of the nuclei. Sections after staining with this dye-reagent require n-butanol as differentiating reagent. Possible interpretation for the increase in staining ability of this dye-reagent under exposure to UV rays has been elucidated and the reason for considering the reaction as Feulgen type has been discussed.

Adrenal Glands↗
PubMed2002

Diffractive optical elements based on Fourier optical techniques: a new class of optics for extreme ultraviolet and soft x-ray wavelengths.

A diffractive optical element, based on Fourier optics techniques, for use in extreme ultraviolet/soft x-ray experiments has been fabricated and demonstrated. This diffractive optical element, when illuminated by a uniform plane wave, will produce two symmetric off-axis first-order foci suitable for interferometric experiments. The efficiency of this optical element and its use in direct interferometric determination of optical constants are also discussed. Its use in direct interferometric determination of optical constants is also referenced. Its use opens a new era in the use of sophisticated optical techniques at short wavelengths.

Journal Article↗
PubMed2006

High-efficiency collector design for extreme-ultraviolet and x-ray applications.

A design of a two-reflection mirror for nested grazing-incidence optics is proposed in which maximum overall reflectivity is achieved by making the two grazing-incidence angles equal for each ray. The design is proposed mainly for application to nonimaging collector optics for extreme-ultraviolet microlithography where the radiation emitted from a hot plasma source needs to be collected and focused on the illuminator optics. For completeness, the design of a double- reflection mirror with equal reflection angles is also briefly outlined for the case of an object at infinity for possible use in x-ray applications.

Journal Article↗
PubMed1981

[Molineinae parasites of mammals].

A revision of Molineinae parasitic in mammals is proposed with the following taxonomic changes: 1) Removal of the genera Ortleppstrongylus Durette-Desset, 1970, from a Bathyergidae of South Africa and Moguranema Yamaguti, 1941, from a Talpidae insectivore of Japan. Both genera are placed in Trichostrongylidae-Cooperiinae for the first, Trichostrongylidae-Haemonchinae for the second. 2) Division of the genus Molineus into two groups separated principally by the arrangement of the bursal rays. a) Molineus sensu stricto, parasitic in Carnivores throughout the world and in South american monkeys; with rays 2 and 3 grouped together and parallel, and with rays 4 equidistant between the 3 and 5. b) Brygoonema n. gen., Hugotnema, n. gen., Nochtia (Nochtia) Travassos and Vogelsang, 1929, and Nochtia (Tenrecola) n. sub. gen., parasitic in Tenrecoidea insectivores of Madagascar and Africa, and Erinacoidea insectivores and lemurs of Africa, with rays 2 and 3 diverging and the papilla of the ray 4 closer to the 3 than the 5. 3) Resurrection of the genus Shattuckius Sandground, 1938 parasitic in Solenodon of Hispaniola. 4) Synonymy of Hooperstrongylus Lie Kian Joe et Ow Yang, 1963 with Pithecostrongylus Lubimov, 1930. The species Molineus vogelianus De Muro, 1933 and M. teocchii Quentin, 1970, parasitic in lemurs are placed in Pithecostrongylus. Hypotheses on the evolution of the Molineinae of mammals are presented, based primarily on the evolution of the bursa. From the basic pattern observed in Molineinae of amphibians and reptiles (rays 2-3 grouped, ray 4 with common base with the 5-6, rays 5-6 grouped), evolution has followed two principal lines: 1) Displacement of the papilla of the ray 4 towards the anterior and disappearance of the common base with the 5-6. 2) Extremities of rays 2-3 and 5-6 converging forming two separate pincer-like formations. Following these and other secondary characters, an evolutionary hierarchy is proposed for the 13 genera. The parasites of Tenrecoidea of Madagascar are apparently of central importance in this evolution. A list of genera and species is given.

Animals↗
PubMed2002

Reflectance enhancement in the extreme ultraviolet and soft x rays by means of multilayers with more than two materials.

Sub-quarterwave multilayer coatings with more than two different materials are shown to provide a reflectance enhancement compared with the standard two-material multilayer coatings when reflectance is limited by material absorption. A remarkable reflectance enhancement is obtained when the materials in the multilayer are moderately absorbing. A simple rule based on the material optical constants is provided to select the most suitable materials for the multilayer and to arrange the materials in the correct sequence in order to obtain the highest possible reflectance. It is shown that sub-quarterwave multilayers generalize the concept of multilayers, of which the standard two-material multilayers are a particular case. Various examples illustrate the benefit of sub-quarter-wave multilayer coatings for highest reflectance in the extreme ultraviolet. Applications for sub-quarterwave multilayer coatings are envisaged for astronomy in the extreme ultraviolet (EUV) and soft x rays and also for future EUY lithography.

Journal Article↗
PubMed1999

[Dual energy X-ray absorptiometry in Ilizarov lower extremity lengthening: preliminary study].

Ilizarov method for lower extremity lengthening has been employed in 107 patients. Some 25% of numerous complications are bony union disturbances. Dual energy X-ray absorptiometry (DEXA) for assessment of new bone formation was introduced to reduce these problems. Detailed densitometry methodology developed on the ground of 93 measurements in 11 patients is presented. Pre-operative measurement was followed by subsequent evaluations done every 3 weeks after the onset of distraction. DEXA was capable of showing the callus 3-4 weeks earlier than conventional radiography. DEXA allows for adjusting the pace of lengthening to the extent of new bone mineralization, evaluation of lengthening achieved, determining the timing for safe removal of the apparatus. The need for temporary rearranging of the apparatus and troublesome image analysis are among the drawbacks of the method.

Absorptiometry, Photon↗
PubMed2006

Focusing multiple high-order harmonics in the extreme-ultraviolet and soft-x-ray regions by a platinum-coated ellipsoidal mirror.

The focusability of multiple high-order harmonics in the extreme-ultraviolet and soft-x-ray regions is described, together with the design and performance of the ellipsoidal mirror used for this purpose. The mirror focuses intense coherent light in the spectral-region from 25 to 40 nm into a 2.4 microm spot size with a focused peak intensity of 6 x 10(13) W/cm2. The focal images indicate that a good beam profile is obtained with a near-Gaussian distribution and a beam quality factor (M2 value) as low as 2.4.

Journal Article↗
PubMed1997

Reproducibility of dual-energy X-ray absorptiometry in the upper extremities in stroke patients.

Bone mineral loss after stroke in affected extremities can increase the prevalence of fractures that interrupt the rehabilitation programme and lower the level of activity. In stroke rehabilitation, precise bone mineral measurement is needed in order to assess the risk of fractures. We defined five regions-of-interest of the upper extremity (proximal humerus, distal forearm, distal radius, distal ulna and hand) consistently, so that the position was comfortable for hemiplegic patients to maintain during the measurement. The aim of this study was to determine whether our method using dual-energy X-ray absorptiometry is useful in hemiplegic patients. Ten normal subjects and 15 hemiplegic patients were studied. In normal subjects the reproducibility of our method was evaluated by repeated measurements of both the right and left sides. In hemiplegic patients the reproducibility was evaluated by repeated measurements of the affected side. The coefficient of variation (CV) values were obtained for BMD (0.7-1.7%) and BMC (0.7-2.3%) in normal subjects, and BMD (1.3-2.1%) and BMC (1.7-5.4%) in hemiplegic patients. The CV for the side-to-side BMD and BMC ratios in the normal subjects ranged from 1.1% to 2.2% and from 1.8% to 3.1%, respectively. Our study shows that the reproducibility of our method is sufficient for application to hemiplegic patients.

Absorptiometry, Photon↗