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The ability of the juvenile female reproductive axis to respond to hormonal stimulation was investigated in a Perciform fish, the striped bass (Morone saxatilis) using various combinations of testosterone (T), GnRH agonist (GnRHa), and pimozide. A long-term treatment with T alone, or T in combination with GnRHa, increased pituitary gonadotropin II (GtH II) levels 2- and 3-fold, respectively, suggesting that T and GnRHa each stimulate GtH II accumulation. Release of the accumulated GtH II could be induced only by high doses of GnRHa in combination with T, indicating that GtH II synthesis and release require different levels of GnRH stimulation. The addition of the dopamine antagonist pimozide did not affect pituitary and plasma GtH II levels but, in response to an additional acute GnRHa challenge, inhibited the release of GtH II. Although ovarian development was slightly stimulated by a combined T and GnRHa treatment, vitellogenesis was generally not initiated. The present study demonstrated that the juvenile striped bass pituitary is responsive to hormonal stimulation, resulting in elevated levels of GtH II in the pituitary and plasma. However, increased plasma levels of GtH II did not result in precocious puberty, suggesting that additional factors are required for the initiation of ovarian development in this teleost. 相似文献
53.
JR García Fernández MA montalbán ML Martín MC Ortiz MA Martínez A García Marcilla 《Canadian Metallurgical Quarterly》1998,43(5):430-432
Acute nonoliguric renal failure developed in a 13-year-old girl, 1 month after the institution of isoniazid therapy because of a positive tuberculin test at school screening. A renal biopsy demonstrated severe crescentic glomerulonephritis with focal interstitial changes. Discontinuation of isoniazid and a short course of steroids and cyclophosphamide therapy were followed by complete recovery. Whereas isoniazid has been shown to induce a lupus-like syndrome and antihistone antinuclear antibodies, our patient displayed none of the clinical or immunological features that are characteristic of drug-induced lupus. Furthermore, none of the identifiable causes for crescentic glomerulonephritis was evident in this girl. To the best of our knowledge this is the first report suggesting a possible association of crescentic glomerulonephritis to isoniazid treatment. 相似文献
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High niobium oxide content in germanate glasses: Thermal,structural, and optical properties 下载免费PDF全文
Lia Mara Marcondes Sérgio Maestri Bianca Sousa Rogeria Rocha Gonçalves Fabia Castro Cassanjes Gael Yves Poirier 《Journal of the American Ceramic Society》2018,101(1):220-230
Niobium alkali germanate glasses were synthesized by the melt‐quenching technique. The ternary system (90‐x)GeO2–xNb2O5–10K2O forms homogeneous glasses with x ranging from 0 to 20 mol%. Samples were investigated by DSC and XRD analysis, FTIR and Raman spectroscopy, and optical absorption. Structural and physical features are discussed in terms of Nb2O5 content. The niobium content increase in the glass network strongly modifies the thermal, structural and optical properties of alkali germanate glasses. DSC, Raman and FTIR analysis suggest niobium addition promotes NbO6 groups insertion close to GeO4 units of the glass network. XRD analysis also pointed out that samples containing high niobium oxide contents exhibit preferential niobium oxide‐rich phase after crystallization after heat treatment, which is similar to orthorhombic Nb2O5. Absorption spectra revealed high transmission range between 400 nm to 6.2 μm, added to a considerably decreased hydroxyl group content as the addition of niobium in the alkali germanate network. The niobium oxide‐rich phase crystallization process was studied and activation energy was determined, as well as nucleation and crystal growth temperatures and time for obtaining transparent glass‐ceramics. 相似文献
57.
Adnane Hamiaz Rudy Klein Xavier Ferrieres Olivier Pascal Jean-Pierre Boeuf Jean-Rene Poirier 《Computer Physics Communications》2012,183(8):1634-1640
The modelling of plasma formation during microwave breakdown is a difficult task because of the strong non-linear coupling between Maxwell?s equations and plasma equations, and of the large plasma density gradients that form during breakdown. An original Finite Volume Time Domain (FVTD) method has been developed to solve Maxwell?s equations coupled with a simplified fluid plasma model and is described in this paper. This method is illustrated with the study of the shielding of a metallic aperture by the plasma generated by an incident high power electromagnetic wave. Typical results obtained with the FVTD method for this shielding problem are shown. 相似文献
58.
S. D. Felicelli D. R. Poirier P. K. Sung 《Metallurgical and Materials Transactions B》2000,31(6):1283-1292
A finite element model for simulating macrosegregation in multicomponent alloys is extended to include the calculation of
pressure and redistribution of gas-forming elements during solidification. The model solves the conservation equations of
mass, momentum, energy, and alloy components, including gas-forming elements such as hydrogen and nitrogen. The results of
transport calculations are contrasted with thermodynamic equilibrium conditions to establish the possible formation of pores,
assuming that there is no barrier to nucleation of the pores. By solving the transport of gaseous solutes and comparing their
Sievert’s pressure with the local pressure, the new mode can predict regions of possible formation of intergranular porosity.
Simulations were performed for a nickel-base alloy (INCONEL 718) in plate castings with equiaxed structure, and the evolution
of microporosity for different initial concentrations of hydrogen and nitrogen was analyzed. The simulations showed that during
solidification and cooling, a large fraction of the hydrogen escapes and a smaller fraction of nitrogen escapes from the casting.
The initial gas concentration is an important factor in porosity formation, but the pressure drop due to shrinkage flow is
not very significant. The resulting gas porosity is rather insensitive to initial nitrogen concentration, but sensitive to
the concentration of hydrogen. 相似文献
59.
Context-sensitive Multiple Task Learning, or csMTL, is presented as a method of inductive transfer which uses a single output neural network and additional contextual inputs
for learning multiple tasks. Motivated by problems with the application of MTL networks to machine lifelong learning systems,
csMTL encoding of multiple task examples was developed and found to improve predictive performance. As evidence, the csMTL method is tested on seven task domains and shown to produce hypotheses for primary tasks that are often better than standard
MTL hypotheses when learning in the presence of related and unrelated tasks. We argue that the reason for this performance
improvement is a reduction in the number of effective free parameters in the csMTL network brought about by the shared output node and weight update constraints due to the context inputs. An examination
of IDT and SVM models developed from csMTL encoded data provides initial evidence that this improvement is not shared across all machine learning models. 相似文献
60.
OBJECTIVE: To describe the steps pharmacists must complete when seeking compensation from third party payers for pharmaceutical care services. DATA SOURCES: Government publications; professional publications, including manuals and newsletters; authors' personal experience. DATA SYNTHESIS: Pharmacists in increasing numbers are meeting with success in getting reimbursed by third party payers for patient care activities. However, many pharmacists remain reluctant to seek compensation because they do not understand the steps involved. Preparatory steps include obtaining a provider/supplier number, procuring appropriate claim forms, developing data collection and documentation systems, establishing professional fees, creating a marketing plan, and developing an accounting system. To bill for specific patient care services, pharmacists need to collect the patient's insurance information, obtain a statement of medical necessity from the patient's physician, complete the appropriate claim form accurately, and submit the claim with supporting documentation to the insurer. Although many claims from pharmacists are rejected initially, pharmacists who work with third party payers to understand the reasons for denial of payment often receive compensation when claims are resubmitted. CONCLUSION: Pharmacists who follow these guidelines for billing third party payers for pharmaceutical care services should notice an increase in the number of paid claims. 相似文献