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1.
In vivo EMG biofeedback was found to be an effective pedagogical tool for removing unwanted left-hand tension in nine violin and viola players. Improvement occurred rapidly and persisted throughout a 5-month follow-up period. Further studies will be necessary to assess the effect of biofeedback independent of placebo effects. The brevity of the method and the magnitude of improvement warrant further investigation. 相似文献
2.
Prof. Dr. J. Oldenburg S. Rost H. Seidel M. Watzka C.R. Müller-Reible 《Medizinische Genetik》2008,20(2):230-235
The recent identification of VKORC1 has made important contributions to our understanding of the vitamin K cycle. The VKORC1 enzyme was shown to be the molecular target of coumarin drugs. Mutations and polymorphisms in coding and noncoding regions of the VKORC1 gene have been shown to cause both a partial to total coumarin resistance and coumarin sensitivity. Availability of molecular diagnostics (VKORC1, CYP2C9) and drug monitoring by HCPLC (determination of coumarin, vitamin K, and vitamin K epoxide levels) is helpful for detecting hereditary and acquired factors influencing coumarin therapy. In the future, these tools may be instrumental in designing individualized oral anticoagulation therapy regimens. 相似文献
3.
M. Tanushev E. M. Myasnikova Dr. Sci A. Yu. Yakovlev 《Biometrical journal. Biometrische Zeitschrift》1987,29(1):93-102
The aim of this study was mathematical formalization of the development of two damage processes in response to the combined action of two different damaging agents. The model allows to obtain the parametric family of distributions for the life-span when the organism's death is due to joint effect of two damage processes. Differing by their probabilistic meaning the notions of a priori (M (t)) and a posteriori (M(y)) conditional mean contributions of each damage process to the final effect of combined injury are introduced. The formulas permitting to compute the M and M values on the basis of survival data parametric analysis are given. 相似文献
4.
Summary The horseradish-peroxidase (HRP) technique was used to visualize the cell bodies of axons projecting to the goldfish pituitary. Following intravenous injections of HRP, HRP reaction products were observed in axons of the rostral pars distalis, proximal pars distalis, neurointermediate lobe, pituitary stalk and in axons coursing from the pituitary into the hypothalamus. HRP-labelled cells in the brain were localized in two regions only — the nucleus preopticus (NPO) pars magnocellularis and pars parvocellularis, and the nucleus lateralis tuberis (NLT) of the hypothalamus. These observations suggest that the NPO and NLT are the source of the neurosecretory innervation of the goldfish pituitary. 相似文献
5.
Dr. Patrick R. Cammarata Lawrence Oakford David Cantu-Crouch Robert Wordinger 《Cell and tissue research》1987,250(3):633-640
Summary The bovine lens capsule has previously been shown to provide an optimal surface for the examination of epithelial cell interaction with a basement membrane. This native substrate has been used to investigate some initial aspects of attachment of mouse blastocysts and trophoblastic cellular outgrowth. Mouse blastocysts were presented to the cell-free humoral side of the anterior lens capsule, incubated for 72 h, and examined by scanning and transmission electron microscopy. Blastocysts hatch and attach from their zonae pellucidae by 30 h. Trophoblastic cells proliferate rapidly in a coronal direction, display extensive surface microvilli, and advance by the extension of numerous filipodia, many of which terminate with bulbous projections. These projections were shown by transmission electron microscopy to contain numerous vacuoles and polysomes. To simulate further the initial blastocyst-uterine interaction, a suspension of lens epithelial cells was introduced to the capsule and permitted to form a monolayer prior to the addition of the blastocysts. At 72 h the monolayer of lens cells remained intact. We observed that: a) lens cells appear to recede from the advancing trophoblastic cells, and b) trophoblastic cells extend beneath the monolayer of lens cells and thereby dislodge the cells from the lens capsule substrate. No infiltration of the capsule by the advancing trophoblastic cells was observed. The lens capsule appears to offer a promising system for the study of trophoblast-epithelial cell interaction on a natural basement membrane. 相似文献
6.
Background
Spidroins are a unique family of large, structural proteins that make up the bulk of spider silk fibers. Due to the highly variable nature of their repetitive sequences, spidroin evolutionary relationships have principally been determined from their non-repetitive carboxy (C)-terminal domains, though they offer limited character data. The few known spidroin amino (N)-terminal domains have been difficult to obtain, but potentially contain critical phylogenetic information for reconstructing the diversification of spider silks. Here we used silk gland expression data (ESTs) from highly divergent species to evaluate the functional significance and phylogenetic utility of spidroin N-terminal domains. 相似文献7.
Dr. F. Tüttelmann 《Medizinische Genetik》2011,23(2):259-266
The cause for infertility which affects about 10–15% of all couples may be found in approximately half of the cases in the male partners who usually exhibit reduced sperm counts in the ejaculate (i.e. oligozoospermia or azoospermia). The clinically most relevant genetic causes of spermatogenic failure are chromosomal aberrations including Klinefelter’s syndrome and Y chromosomal microdeletions of the AZF loci. Aside from the full clinical picture of cystic fibrosis, mutations in the CFTR gene can cause an isolated obstructive azoospermia without spermatogenic impairment. Genetic investigations should depend on the results of andrological examinations. Chromosomal aberrations are detected more frequently with decreasing sperm counts, where autosomes (e.g. translocations) are predominantly involved in men with oligozoospermia whereas in 10–15% azoospermia is caused by Klinefelter’s syndrome. Classical AZF deletions are found only in men with severe oligospermia or azoospermia and have a prognostic value. In contrast to men with AZFc deletions, carriers of complete AZFa and AZFb deletions have virtually no chance for testicular sperm extraction and a testicular biopsy is not advised. Rare cases of male infertility may be caused by specific syndromes or sperm defects (e.g. globozoospermia and disorders of ciliary structure). 相似文献
8.
9.
Electron-microscopic and immunocytochemical analyses of Weibel-Palade bodies in the human umbilical vein during pregnancy 总被引:3,自引:0,他引:3
Summary The present study was done to elucidate the biological significance of the Weibel-Palade body of human umbilical vein endothelial cells. Quantitative determinations of these endothelial-specific granules throughout pregnancy revealed that their numbers and size per cell profile were maintained at low levels from 12 to 19 weeks of gestation; then both rapidly increased from 33 weeks to full term. This increase coincided with the development of the rough endoplasmic reticulum and an increase in the number of endothelial cell pinocytotic vesicles. Light-microscopic peroxidase anti-peroxidase and electron-microscopic protein A-gold techniques provided evidence that factor VIII-related antigen was localized in the Weibel-Palade bodies. Furthermore, in vitro treatment of incubated umbilical vein tissue with compound 48/80, a histamine releaser, induced degranulation of Weibel-Palade bodies from the endothelium. The present study indicates that Weibel-Palade bodies are storage sites of both histamine and factor VIII-related antigen and have an important role in the obliteration of this vessel. 相似文献
10.
Citromicrobium bathyomarinum, a novel aerobic bacterium isolated from deep-sea hydrothermal vent plume waters that contains photosynthetic pigment-protein complexes.
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We have taxonomically and phylogenetically characterized a new aerobic bacterial strain (JF-1) that contains photosynthetic pigment-protein complexes and which was recently isolated from black smoker plume waters of the Juan de Fuca Ridge. Strain JF-1 is a gram-negative, yellow-pigmented, motile bacterium that is salt-, pH-, and thermotolerant. These properties are consistent with an oligotrophic adaptation to varied environmental conditions thought to exist around deep-sea hydrothermal vents. The analysis of 16S rDNA sequences revealed that strain JF-1 forms a separate phylogenetic branch between the genus Erythromonas and the Erythromicrobium-Porphyrobacter-Erythrobacter cluster within the alpha subclass of the Proteobacteria. The taxonomic name Citromicrobium bathyomarinum (gen. nov., sp. nov.) is proposed for strain JF-1. 相似文献