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RD Jolly JJ Hopwood NR Marshall KS Jenkins DJ Thompson KE Dittmer 《New Zealand veterinary journal》2013,61(3):183-188
Abstract AIM: To investigate and characterise an inborn error of metabolism in a dog with skeletal and ocular abnormalities. METHODS: A 2.5-year-old small male Miniature Poodle-like dog was presented with gross joint laxity and bilateral corneal opacities. Clinical examination was augmented by routine haematology, serum chemistry, radiographs, pathology, enzymology and molecular genetic studies. Euthanasia was requested when the dog was 3 years of age because of progressively decreasing quality of life. RESULTS: Radiology revealed generalised epiphyseal dysplasia, malformed vertebral bodies, luxation/subluxation of appendicular and lumbosacral joints with hypoplasia of the odontoid process and hyoid apparatus. These clinical and radiographic findings, together with a positive urinary Berry spot test for mucopolysaccharides, and metachromatic granules in leucocytes, were indicative of a mucopolysaccharidosis (MPS), a lysosomal storage disease. Histological lesions included vacuolation of stromal cells of the cornea, fibroblasts, chondrocytes, macrophages and renal cells. The brain was essentially normal except for moderate secondary Wallerian-type degeneration in motor and sensory tracts of the hind brain. Dermatan sulphate-uria was present and enzymology revealed negligible activity of N-acetylgalactosamine-4-sulphatase, also known as arylsulphatase B, in cultured fibroblasts and liver tissue. A novel homozygous 22 base pair (bp) deletion in exon 1 of this enzyme's gene was identified (c.103_124del), which caused aframe-shift and subsequent premature stop codon. The “Wisdom pure breed-mixed breed” test reported the dog as a cross between a Miniature and Toy Poodle. CONCLUSIONS: The clinicopathological features are similar to those of MPS type VI as previously described in dogs, cats and other species, and this clinical diagnosis was confirmed by enzymology and molecular genetic studies. This is an autosomal recessively inherited lysosomal storage disease. CLINICAL RELEVANCE: The prevalence of MPS VI in Miniature or Toy Poodles in New Zealand and elsewhere is currently unknown. Due to the congenital nature of the disorder, malformed pups may be subject to euthanasia without investigation and the potential genetic problem in the breed may not be fully recognised. The establishment of a molecular genetic test now permits screening for this mutation as a basis to an informed breeding policy. 相似文献
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Impact of Endocrine‐Disrupting Chemicals on Reproductive Function in Zebrafish (Danio rerio) 下载免费PDF全文
The prevalence of endocrine‐disrupting chemicals (EDCs) in the aquatic environment has been associated with the wide detection of alterations in the development and physiology of vertebrates. Zebrafish, as a model species, has been extensively used in toxicological research. In this review, we focus on recent published evidence of the harmful effects of EDCs on reproductive function in zebrafish, including skewed sex ratio, immature gonads, diminished sexual behaviour, decreased sperm count, reduced spawning and fertilization. These impairments mostly result from disruption to sex‐steroid hormones induced by endocrine disruptors. We also discuss other effects of exposure to EDCs. In EDC exposure research, despite incomplete assessments of altered gonad histopathology and sexual behaviour, these present potential effective biomarkers or pathways for evaluating the reproductive function in zebrafish on EDC exposure. To date, the pernicious effects of some EDCs on the reproductive performance in laboratory zebrafish are well understood; however, similar alterations remain for further determination in wild‐type fish and more kinds of EDCs. More studies should be performed under established scientific regulatory criteria to investigate the impact of EDCs on reproduction in zebrafish. Moreover, further research is required to explain the definite mechanism of sexual differentiation, which helps in understanding the shift of sexual phenotype with EDC exposure. 相似文献
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Measurements of the equation of state of deuterium at the fluid insulator-metal transition 总被引:1,自引:0,他引:1
GW Collins Da Silva LB P Celliers DM Gold ME Foord RJ Wallace A Ng SV Weber KS Budil R Cauble 《Science (New York, N.Y.)》1998,281(5380):1178-1181
A high-intensity laser was used to shock-compress liquid deuterium to pressures from 22 to 340 gigapascals. In this regime deuterium is predicted to transform from an insulating molecular fluid to an atomic metallic fluid. Shock densities and pressures, determined by radiography, revealed an increase in compressibility near 100 gigapascals indicative of such a transition. Velocity interferometry measurements, obtained by reflecting a laser probe directly off the shock front in flight, demonstrated that deuterium shocked above 55 gigapascals has an electrical conductivity characteristic of a liquid metal and independently confirmed the radiography. 相似文献
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KS Johnson JH Thywissen NH Dekker KK Berggren AP Chu R Younkin M Prentiss 《Science (New York, N.Y.)》1998,280(5369):1583-1586
The spatially dependent de-excitation of a beam of metastable argon atoms, traveling through an optical standing wave, produced a periodic array of localized metastable atoms with position and momentum spreads approaching the limit stated by the Heisenberg uncertainty principle. Silicon and silicon dioxide substrates placed in the path of the atom beam were patterned by the metastable atoms. The de-excitation of metastable atoms upon collision with the surface promoted the deposition of a carbonaceous film from a vapor-phase hydrocarbon precursor. The resulting patterns were imaged both directly and after chemical etching. Thus, quantum-mechanical steady-state atom distributions can be used for sub-0.1-micrometer lithography. 相似文献
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Pitzer KS 《Science (New York, N.Y.)》1963,139(3553):414
The bonding in rare gas fluorides is similar to that in halogen polyfluorides, and the stability of such compounds should depend primarily on the ionization potential of the central atom. This theory is consistent with findings for all known compounds of the system and yields predictions concerning other systems. 相似文献
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Polar stratospheric clouds (PSCs) are important for the chemical activation of chlorine compounds and subsequent ozone depletion. Solid PSCs can form on sulfuric acid tetrahydrate (SAT) (H2SO4·4H2O) nuclei, but recent laboratory experiments have shown that PSC nucleation on SAT is strongly hindered. A PSC formation mechanism is proposed in which SAT particles melt upon cooling in the presence of HNO3 to form liquid HNO3-H2SO4-H2O droplets 2 to 3 kelvin above the ice frost point. This mechanism offers a PSC formation temperature that is defined by the ambient conditions and sets a temperature limit below which PSCs should form. 相似文献
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ECR Leonel V Bento‐Silva KS Ambrozio HS Luna EV Costa e Silva CESN Zúccari 《Reproduction in domestic animals》2013,48(6):e85-e87
The aim of this study was to test the use of mechanical and mechanical‐enzymatic methods, saline solution (SS), and PBS solution for the manipulation and isolation of mare ovarian preantral follicles (PAFs). The ovaries were subjected to mechanical isolation (mixer) alone or in association with enzymatic digestion (collagenase). Incubation times of 10 and 20 min were employed. In the first group, 4.1 ± 4.9 PAFs were harvested with the mechanical‐enzymatic method vs 71.1 ± 19.2 with the mechanical procedure, showing a significant difference between methods; using SS and PBS, these numbers were 35.7 ± 34.3 and 39.6 ± 39.6, respectively, with no significant difference between solutions. In the second group, there was significant difference between methods, with 7.1 ± 10.6 follicles harvested with the mechanical‐enzymatic method vs 63.2 ± 22.9 with the mechanical procedure; using SS and PBS, means were 35.5 ± 36.4 and 34.9 ± 31.1, respectively. The mechanical method proved more effective than the mechanical‐enzymatic approach. Both SS and PBS can be used as a media for equine PAFs preparation. 相似文献