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11.
A progestin receptor (PR) has been detected in the olfactory organ of the trout Salmo trutta fario. The specificity of this receptor was high for 17α,20β‐dihydroxy‐4‐pregnen‐3‐one (17α,20β‐DP), but it also bound 17α‐hydroxy‐progesterone (17α‐OHP) and 21‐hydroxyprogesterone (21‐OHP), even when present at low concentrations (10‐fold in relative binding affinity assay). Progesterone (P) competed effectively at much higher concentrations (1,000‐fold in relative binding affinity assay). Immunohistochemical studies carried out with three different monoclonal antibodies against human progesterone receptor (hPR), chicken progesterone receptor hinge region (cPR), and chicken progesterone receptor A/B domain (PR22), revealed that immunoreactivity was present in the epithelium of the olfactory organ of females and males of the trout Salmo trutta fario only against hPR. Western blotting showed two hPR immunoreactive bands of about 62 and 66 kDa. Finally, a portion of the cDNA of about 300 nucleotides extending over the DNA binding domain and the ligand binding domain was cloned and sequenced, revealing a high degree of sequence homology of the PR in Salmo trutta fario with the PR in other teleosts. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
12.
The endocrine pancreas of three red frogs was studied immunohistochemically. It consisted of islets and diffuse endocrine cells. The islets showed a mammalian-like arrangement with a central core of B cells and a peripheral mantle of A/PP cells. A few D and VIP cells were also present. Several regulatory peptides were co-localized in the same endocrine cells by consecutive sections and double-labeling studies. The A/PP cells were formed by subpopulations of cells showing various types of immunoreactivity and varying degrees of immunolabeling. Generally, glucagon/pancreatic polypeptide, glucagon/pancreatic polypeptide/peptide tyrosine tyrosine and glucagon/pancreatic polypeptide/neuropeptide tyrosine immunoreactivities were present in the islets and in the endocrine cells scattered throughout the exocrine parenchyma (the diffuse component). Some specimens, mainly belonging to Rana dalmatina, showed evident periinsular halos around the islets. The diffuse component was abundant, and mainly contained A/PP cells. It formed a net across the exocrine parenchyma; its interrelationship with the latter might occur by a paracrine mechanism.  相似文献   
13.
The aim of this work was to evaluate the biogenic amine (BA) content during the ripening of both bovine and ovine cheeses obtained using milk subjected to a homogenization treatment at 100 MPa before cheese-making. The data obtained were compared with those from cheeses produced by the same milks without any treatment or thermized. The results showed that both microbial ecology and BA concentrations of cheeses during ripening were significantly influenced by the type of milk used for cheese-making and by the treatment applied to the raw materials. In particular, the microbial counts found in Caciotta indicated that the high pressure homogenization (HPH) of milk significantly reduced the presence of the yeasts, Micrococcaceae and lactobacilli at the end of ripening. On the other hand, the HPH treatment of milk favoured the proliferation of yeasts in ovine cheese. Moreover, the ovine cheeses were characterized by a remarkably higher accumulation of BA than bovine cheeses. However, the HPH treatment of milk was able to drastically reduce the biogenic amine concentrations in both cheese typologies at the end of ripening.  相似文献   
14.
In standard finite element simulations of groundwater flow the correspondence between hydraulic head gradients and groundwater fluxes is represented by the stiffness matrix. In two‐dimensional problems the use of linear triangular elements on Delaunay triangulations guarantees a stiffness matrix of type M. This implies that the local numerical fluxes are physically consistent with Darcy's law. This condition is fundamental to avoid the occurrence of local maxima or minima, and is of crucial importance when the calculated flow field is used in contaminant transport simulations or pathline evaluation. In three spatial dimensions, the linear Galerkin approach on tetrahedra does not lead to M‐matrices even on Delaunay meshes. By interpretation of the Galerkin approach as a subdomain collocation scheme, we develop a new approach (OSC, orthogonal subdomain collocation) that is shown to produce M‐matrices in three‐dimensional Delaunay triangulations. In case of heterogeneous and anisotropic coefficients, extra mesh properties required for M‐stiffness matrices will also be discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
15.
Generalised additive models (GAMs) allow for flexible functional dependence of a response variable on covariates. The aim of this article is to provide an accessible overview of GAMs based on the penalised likelihood approach with regression splines. In contrast to the classical backfitting, the penalised likelihood framework taken here provides researchers with an efficient computational method for automatic multiple smoothing parameter selection, which can determine the functional form of any relationship from the data. We illustrate through an example how the use of this methodology can help to gain insights into medical research.  相似文献   
16.
The aim was to study the effects of Debaryomyces hansenii and Yarrowia lipolytica strains, used with lactic acid starter cultures (Lactobacillus plantarum), in the manufacture of dried fermented sausages in order to understand their effects on volatile profile, biogenic amine content and sensory properties. The experimental data showed that every yeast strain produced a specific profile of volatile metabolic products. The yeasts also gave sausages with distinctive sensory properties. The degree of mincing also influenced these properties, but none of these factors had significant influence upon the accumulation of biogenic amines.  相似文献   
17.
The 5S ribosomal RNA is a very suitable target for easy, rapid and inexpensive fish species identification due to its structure, consisting of a conserved region followed by a species-specific noncoding region called ‘nontranscribed spacer’. We have exploited this species-specificity in length and sequence to discriminate among fish species which can be subjected to substitution in the fish markets. After sequencing and alignment of the corresponding portions of the 5S rRNAs of different fish species, we have designed the primer pairs necessary for PCR amplification on the DNA traits which most diverged and a primer pair on conserved regions. Our results have shown the feasibility, simplicity and reliability of the proposed approach for the detection of mislabelling or fraudulent substitution of fish species.  相似文献   
18.
This paper describes a new logic style called Power Rail Logic (PRL), which is compatible with direct-coupled FET logic (DCFL) circuits. Multiplexors, latches, flip-flops, and exclusive-OR gates can be built using this logic style. Compared to DCFL, PRL uses fewer transistors, has larger noise margins, and up to 40% lower power-delay products. A test chip containing 32-b barrel shifters designed in DCFL and in PRL was successfully fabricated and tested. Test results are given for both circuits  相似文献   
19.
This paper presents a novel class of preconditioners for the iterative solution of the sequence of symmetric positive‐definite linear systems arising from the numerical discretization of transient parabolic and self‐adjoint partial differential equations. The preconditioners are obtained by nesting appropriate projections of reduced‐order models into the classical iteration of the preconditioned conjugate gradient (PCG). The main idea is to employ the reduced‐order solver to project the residual associated with the conjugate gradient iterations onto the space spanned by the reduced bases. This approach is particularly appealing for transient systems where the full‐model solution has to be computed at each time step. In these cases, the natural reduced space is the one generated by full‐model solutions at previous time steps. When increasing the size of the projection space, the proposed methodology highly reduces the system conditioning number and the number of PCG iterations at every time step. The cost of the application of the preconditioner linearly increases with the size of the projection basis, and a trade‐off must be found to effectively reduce the PCG computational cost. The quality and efficiency of the proposed approach is finally tested in the solution of groundwater flow models. © 2016 The Authors. International Journal for Numerical Methods in Engineering Published by John Wiley & Sons Ltd.  相似文献   
20.
We are concerned with the mapping on high performance hybrid architectures of a parallel software implementing a two level overlapping domain decomposition, that is, along space and time directions, of the four dimensional variational data assimilation model. The reference architecture belongs to the SCoPE (Sistema Cooperativo Per Elaborazioni scientifiche multidisciplinari) data center, located at University of Naples Federico II. We consider the initial boundary problem of the shallow water equation and analyse both strong and weak scaling. Keeping the efficiency always greater than and about in most cases, we experimentally find that the isoefficiency function grows a little more than linearly with respect to the number of processes. Results, obtained by using the parallel computing toolbox of MATLABR2013a, are in agreement with the algorithm's performance prevision based on the scale up factor, confirming the appropriate mapping of the algorithm on the hybrid architecture.  相似文献   
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