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1.
It has been found that fertility alpha 2-microglobulin content in male and female serum does not exceed 20 ng/ml and 40 ng/ml, respectively. A high level of fertility alpha 2-microglobulin was found in the serum in early pregnancy, with its concentration decreased by parturition.  相似文献   
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White rats were immunized against fragment of diazepam-binding inhibitor octadecaneuropeptide (ODN) with conjugate ODN bovine serum albumin. This rats have reduced reactions of fear and anxiety in stress model of "open field" and in conflict Vogel test; their pain sensitivity ("tail flick" test) was lowered. The number and intensity of generalized seizure reactions after injection of pentylenetetrazole were decreased. The results show that active immunization to endogenous ODN has stress--protective and anti-seizure effects.  相似文献   
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The type specimen ofGonioloboceras goniolobum (Meek), rediscovered by Spath in the British Museum, is the foundation for a more accurate comparative study of this and other species ofGonioloboceras.Gonioloboceras described asG. goniolobum byElias in 1938 is differentiated asGonioloboceras schmidti, new species. Suture sets (new term) for several growth stages inG. goniolobum (Meek),G. welleriSmith,G. schmidtiElias, G.eliasiMiller &Owen, andG. asiaticumLibrovitch are assembled and used for differentiation of the species.The Kazakhstan goniatite faunule containingG. asiaticum is considered of very late Pennsylvanian age.  相似文献   
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Minimal photosynthetic catalytic F1() core complexes, containing equimolar ratios of the and subunits, were isolated from membrane-bound spinach chloroplast CF1 and Rhodospirillum rubrum chromatophore RrF1. A CF1-33 hexamer and RrF1-11 dimer, which were purified from the respective F1() complexes, exhibit lower rates and different properties from their parent F1-ATPases. Most interesting is their complete resistance to inhibition by the general F1 inhibitor azide and the specific CF1 inhibitor tentoxin. These inhibitors were earlier reported to inhibit multisite, but not unisite, catalysis in all sensitive F1-ATPases and were therefore suggested to block catalytic site cooperativity. The absence of this typical property of all F1-ATPases in the 11 dimer is consistant with the view that the dimer contains only a single catalytic site. The 33 hexamer contains however all F1 catalytic sites. Therefore the observation that CF1-33 can bind tentoxin and is stimulated by it suggests that the F1 subunit, which is required for obtaining inhibition by tentoxin as well as azide, plays an important role in the cooperative interactions between the F1-catalytic sites.Abbreviations CF0F1 chloroplast F0F1 - CF1 chloroplast F1 - CF1 chloroplast F1 subunit - CF1 chloroplast F1 subunit - CF1() a complex containing equal amounts of the CF1 and subunits - MF1 mitochondrial F1 - RrF0F1 Rhodospirillum rubrum F0F1 - RrF1 R. rubrum F1 - RrF1 R. rubrum F1 subunit - RrF1 R. rubrum F1 subunit - RrF1() a complex containing equal amounts of the RrF1 and subunits - Rubisco Ribulose-1,5-bisphosphate carboxylase - TF1 thermophilic bacterium PS3 F1  相似文献   
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Five models have been built by the ICM method for the Comparative Modeling section of the Meeting on the Critical Assessment of Techniques for Protein Structure Prediction. The targets have homologous proteins with known three-dimensional structure with sequence identity ranging from 25 to 77%. After alignment of the target sequence with the related three-dimensional structure, the modeling procedure consists of two subproblems: side-chain prediction and loop prediction. The ICM method approaches these problems with the following steps: (1) a starting model is created based on the homologous structure with the conserved portion fixed and the noncon-served portion having standard covalent geometry and free torsion angles; (2) the Biased Probability Monte Carlo (BPMC) procedure is applied to search the subspaces of either all the nonconservative side-chain torsion angles or torsion angles in a loop backbone and surrounding side chains. A special algorithm was designed to generate low-energy loop deformations. The BPMC procedure globally optimizes the energy function consisting of ECEPP/3 and solvation energy terms. Comparison of the predictions with the NMR or crystallographic solutions reveals a high proportion of correctly predicted side chains. The loops were not correctly predicted because imprinted distortions of the backbone increased the energy of the near-native conformation and thus made the solution unrecognizable. Interestingly, the energy terms were found to be reliable and the sampling of conformational space sufficient. The implications of this finding for the strategies of future comparative modeling are discussed. © 1995 Wiley-Liss, Inc.  相似文献   
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The expression of CEA was studied with the help of rabbit antibody and CEA-specific lectin-krustacin in pepsinogen positive gastric glands near carcinomas and in gastric mucosa with intestinal metaplasia and dysplasia of the epithelium without neoplasia. CEA-krustacin was revealed in 20 out of 41 cases and CEA-antibody in 2 out of 41 cases of gastric glands in mucosa near carcinomas. The results of investigation discover the development in the gastric glands near carcinoma subcellular components. Paraneoplastic phenomenon was found in the majority of the cases.  相似文献   
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Layered lithium–nickel–cobalt–manganese oxide (NCM) materials have emerged as promising alternative cathode materials owing to their high energy density and electrochemical stability. Although high reversible capacity has been achieved for Ni‐rich NCM materials when charged beyond 4.2 V versus Li+/Li, full lithium utilization is hindered by the pronounced structural degradation and electrolyte decomposition. Herein, the unexpected realization of sustained working voltage as well as improved electrochemical performance upon electrochemical cycling at a high operating voltage of 4.9 V in the Ni‐rich NCM LiNi0.895Co0.085Mn0.02O2 is presented. The improved electrochemical performance at a high working voltage at 4.9 V is attributed to the removal of the resistive Ni2+O rock‐salt surface layer, which stabilizes the voltage profile and improves retention of the energy density during electrochemical cycling. The manifestation of the layered Ni2+O rock‐salt phase along with the structural evolution related to the metal dissolution are probed using in situ X‐ray diffraction, neutron diffraction, transmission electron microscopy, and X‐ray absorption spectroscopy. The findings help unravel the structural complexities associated with high working voltages and offer insight for the design of advanced battery materials, enabling the realization of fully reversible lithium extraction in Ni‐rich NCM materials.  相似文献   
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Copper-containing ferroxidase ceruloplasmin (Cp) forms binary and ternary complexes with cationic proteins lactoferrin (Lf) and myeloperoxidase (Mpo) during inflammation. We present an X-ray crystal structure of a 2Cp-Mpo complex at 4.7 Å resolution. This structure allows one to identify major protein–protein interaction areas and provides an explanation for a competitive inhibition of Mpo by Cp and for the activation of p-phenylenediamine oxidation by Mpo. Small angle X-ray scattering was employed to construct low-resolution models of the Cp-Lf complex and, for the first time, of the ternary 2Cp-2Lf-Mpo complex in solution. The SAXS-based model of Cp-Lf supports the predicted 1∶1 stoichiometry of the complex and demonstrates that both lobes of Lf contact domains 1 and 6 of Cp. The 2Cp-2Lf-Mpo SAXS model reveals the absence of interaction between Mpo and Lf in the ternary complex, so Cp can serve as a mediator of protein interactions in complex architecture. Mpo protects antioxidant properties of Cp by isolating its sensitive loop from proteases. The latter is important for incorporation of Fe3+ into Lf, which activates ferroxidase activity of Cp and precludes oxidation of Cp substrates. Our models provide the structural basis for possible regulatory role of these complexes in preventing iron-induced oxidative damage.  相似文献   
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