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61.
Light treatment has been used as a non-pharmacological tool to help mitigate poor sleep quality frequently found in older people. In order to increase compliance to non-pharmacological light treatments, new, more efficacious light-delivery systems need to be developed. A prototype personal light-treatment device equipped with low brightness blue light-emitting diodes (LEDs) (peak wavelength near 470 nm) was tested for its effectiveness in suppressing nocturnal melatonin, a measure of circadian stimulation. Two levels of corneal irradiance were set to deliver two prescribed doses of circadian light exposure. Eleven older subjects, between 51 and 80 yrs of age who met the selection criteria, were exposed to a high and a low level of light for 90 min on separate nights from the personal light-treatment device. Blood and saliva samples were collected at prescribed times for subsequent melatonin assay. After 1 h of light exposure, the light-induced nocturnal melatonin suppression level was about 35% for the low-light level and about 60% for the high-light level. The higher level of blue light suppressed melatonin more quickly, to a greater extent over the course of the 90 min exposure period, and maintained suppression after 60 min. The constant exposure of the low-light level resulted in a decrease in nocturnal melatonin suppression for the last sampling time, whereas for the high-light level, suppression continued throughout the entire exposure period. The present study performed with healthy adults suggests that the tested personal light-treatment device might be a practical, comfortable, and effective way to deliver light treatment to those suffering from circadian sleep disorders; however, the acceptance and effectiveness of personal light-treatment devices by older people and by other segments of the population suffering from sleep disorders in a real-life situation need to be directly tested. (Author correspondence: )  相似文献   
62.
This is an account of the movement of photography as art into the objectivity of the camera image as scientific evidence. On arrival at Cornell University, Collier did not appreciate the extreme flexibility of this department, primarily dedicated to applied anthroplogy, and thereby more open to diverse human data than other branches of the field. The action‐problem‐solving Cornell students and behavioral specialists leapt over theoretical obstacles and directly utilized photographic insights both projectively and in precise content analysis. But the future challenge of visual anthropology came with the text of the moving image and the completeness of filmic understanding.  相似文献   
63.
We describe the synthesis, MMP-2 and 9 potency, and in vitro evaluation of a series of α-sulfone hydroxmate MMP inhibitors conjugated to a series of dyes with different absorption/emission lamina maxima’s that can be used to visualize tumors.  相似文献   
64.
Glucokinase (hexokinase IV) continues to be a compelling target for the treatment of type 2 diabetes given the wealth of supporting human genetics data and numerous reports of robust clinical glucose lowering in patients treated with small molecule allosteric activators. Recent work has demonstrated the ability of hepatoselective activators to deliver glucose lowering efficacy with minimal risk of hypoglycemia. While orally administered agents require a considerable degree of passive permeability to promote suitable exposures, there is no such restriction on intravenously delivered drugs. Therefore, minimization of membrane diffusion in the context of an intravenously agent should ensure optimal hepatic targeting and therapeutic index. This work details the identification a hepatoselective GKA exhibiting the aforementioned properties.  相似文献   
65.
The phylogeny and diagenesis of Pleistocene and Recent bivalves were studied immunologically by use of a conventional antiserum elicited against an EDTA‐soluble macromolecular extract from shells of the modern bivalve mollusc Mercenaria mercenaria. ELISA tests of the antiserum with shell fragments of a wide range of modern bivalves gave taxonomically significant results. The antiserum reacted with palaeoheterodonts and heterodonts but not with representatives of other bivalve subclasses. This phylogenetic reactivity was also apparent in tests with fossil shells, although the specificity and overall strength of the reaction were both reduced. Absorption of the antiserum with etched shell powders of various (palaeo)heterodonts yielded more specific antibody preparations.

Investigations of shell matrix diagenesis, using the anti‐Mercenaria serum, demonstrated that small amounts of original determinants could be detected even in fossils over one million years old. The reactivity of the serum with extracts of fossil Mercenaria decreased with sample age. The relationship between serum reactivity and the degree of amino acid racemization was almost linear. Clearly, the various determinants to which antibodies were elicited were being destroyed at different rates.  相似文献   
66.
The Early Cambrian organism Olivooides is known from both embryonic and post-embryonic stages and, consequently, it has the potential to yield vital insights into developmental evolution at the time that animal body plans were established. However, this potential can only be realized if the phylogenetic relationships of Olivooides can be constrained. The affinities of Olivooides have proved controversial because of the lack of knowledge of the internal anatomy and the limited range of developmental stages known. Here, we describe rare embryonic specimens in which internal anatomical features are preserved. We also present a fuller sequence of fossilized developmental stages of Olivooides, including associated specimens that we interpret as budding ephyrae (juvenile medusae), all of which display a clear pentaradial symmetry. Within the framework of a cnidarian interpretation, the new data serve to pinpoint the phylogenetic position of Olivooides to the scyphozoan stem group. Hypotheses about scalidophoran or echinoderm affinities of Olivooides can be rejected.  相似文献   
67.
The fine structure of the symbiotic alga isolated from the formainiferan Archaias angulatus (Fichtel et Moll) DeMontfort is typical of the Chlorophyceae of the volvocalean and chlorococcalean lines. Spherical non-motile cells, 10–14 μm in diameter, characterise the dominant life cycle phase. Long oval motile forms with truncated apices are present 3–5 days after transfer to fresh medium. The pyrenoids are embedded anteriorly in the singly bilobed chloroplast and are surrounded by a sheath of starch platelets. In spite of the non-motile state of cells in older cultures (which is perhaps a reflection of its normally symbiotic condition), the alga is identified as a species of the volvocalean genus Chlamydomonas and is named C. hedleyi sp. nov.

The symbiont has no vitamin or organic requirements but growth is increased threefold in the presence of thiamine, and twofold in the presence of 1 μm glutamic acid, histidine and methionine. Urea was the best nitrogen source tested. Purines and pyrimidines did not serve as nitrogen sources. Chlamydomonas hedleyi grows well in a salinity range of 6->52‰. and a pH range of 6–8·5, 7·04 × 10-7 m carbon h-1 g-1 was fixed by the symbiont, 57% being released into the medium as a chromatographically homogeneous organic molecule provisionally identified as mannitol.  相似文献   
68.
Abelmoschus enbeepeegearense J. John et al. is a new species occurring at low elevations in the Western Ghats of India, comprising Kerala, Karnataka and Tamil Nadu. The taxon is morphologically allied to A. moschatus subsp. moschatus, A. moschatus subsp. tuberosus and A. crinitus, but easily distinguishable by virtue of its orthotropic branching, 3–5‐angled leaves, glandular hairy plant body with whitish waxy secretions, glandular non‐setose epiclayx segmens which is more than eight in number and ovate hirsute fruits with a short mucro at the apex. It can be crossed with all three taxa with varying degree of success, but the hybrids are sterile. The material belonging to it was earlier identified as and placed under A. moschatus Medik. The taxon is described and illustrated with notes on its phenology, ecology and distribution. In additions, a key to all Abelmoschus taxa occurring in India is provided.  相似文献   
69.
70.
We describe the semen characteristics of a 21-year old “mangalarga” stallion living under natural temperature and photoperiod conditions in São José do Rio Pardo, São Paulo, Brazil (latitude 21°36' S; longitude 46°53' W). The horse fed on natural pasture and a nutritionally balanced feed twice a day (11:00 and 17:00 h). Water and a mineral supplement were available “ad libitum”. Semen was collected for over 36 months (Oct 89-Dec 92) almost daily between 08:00 and 10:00 h by an artificial vagina and evaluated for volume of ejaculate, spermatozoa motility and concentration by standard procedures. Analysis of data from a total of 128-days was performed according to the Fast Fourier Transform Technique (FFT). Statistically significant periods of 7-day were demonstrated for volume, motility, and spermatozoa concentration. Circaseptan rhythms and, particularly, the circannual rhythm (already described in a previous publication) are probably related to ecological diversity and reproductive strategies.  相似文献   
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