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1.
Physical activity and risedronate sodium have effects on metabolic bone diseases, maintaining the integrity of bone tissue. Our objective was to evaluate the effects of swimming associated with risedronate as a prophylactic means in osteopenic bone of ovariectomized rats. A total of 24 animals of the Wistar strain were used and separated into four groups containing six animals: Ovariectomy (OVX), ovariectomy and swimming (OVXS), ovariectomy and risedronate (OVXM), ovariectomy, risedronate and swimming (OVXMS). The effectiveness of the treatments were evaluated using the tibia by means of biomechanical, radiographic, histomorphometric analyzes. Statistical analysis was performed by the non-parametric Kruskal–Wallis test (p < 0.05). The OVXM and OVXMS groups showed higher values compared to OVX in maximum strength and rigidity. Microscopic analysis showed increased trabecular bone in the OVXM group in relation to the others, and in the OVXMS compared to OVXS. Proximal densitometry in the OVXM and OVXMS groups showed higher values than the OVX and OVXS groups. There were no significant differences in overall densitometry. In conclusion, when comparing the prophylactic means, risedronate was able to preserve bone mass significantly, unlike exercise where an improvement of bone tissue was observed, although not significant, and when swimming and risedronate are combined the result was even better. 相似文献
2.
胡斌 《广东微量元素科学》1997,4(9):51-55
儿童缺锌是较普遍的社会现象,济南泉城微量元素生命研究所研制的复合蛋白锌系采用生物技术转化而得到的一种蛋白复合物,属生物合成的有机微量元素,经急性和长期毒性试验均未发现毒副作用,经检测不含兴奋剂,用于临床后,对纠正偏食厌食,反复呼吸道感染和智力低下等近千例儿童疾患,显示了可喜的临床效果,证明是优质有机补锌剂。 相似文献
3.
E. Marklová 《Chromatographia》1997,45(1):195-198
Summary Thin-layer chromatography (TLC) is a rapid, reliable and inexpensive screening technique for diagnosis of inherited metabolic
diseases (IMD). Our screening program encompasses five main situations where the use of TLC is considered to be vindicated:
(i) analysis of amino acids; (ii) screening for sugar defects; (iii) detection of pathological oligosaccharidurias; (iv) screening
for organic acid disorders; and (v) detection of abnormalities in tryptophan metabolism. Examples are presented of chromatograms
obtained from pathological samples.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
4.
微量元素与防病治病 总被引:8,自引:3,他引:8
宫振沛 《广东微量元素科学》2002,9(12):54-61
介绍了微量元素在防治疾病中的作用及对健康长寿的意义,涉及人体必需微量元素,有害元素,有机锗,微量元素是健康长寿的重要手段以及微量元素与现代文明病。 相似文献
5.
金属蛋白研究中几个值得注意的动向 总被引:5,自引:0,他引:5
本文叙述了金属蛋白和金属酶研究中近年来几个值得注意的发展动向,即与金属离子相关的疾病(特别是神经退行性疾病)、金属离子在蛋白质的折叠、聚集和装配中的作用,金属伴侣分子、金属蛋白的设计和构建、金属蛋白与DNA相互作用。 相似文献
6.
Kozyr AV Kolesnikov AV Aleksandrova ES Sashchenko LP Gnuchev NV Favorov PV Kotelnikov MA Iakhnina EI Astsaturov IA Prokaeva TB Alekberova ZS Suchkov SV Gabibov AG 《Applied biochemistry and biotechnology》1998,75(1):45-61
DNA-hydrolyzing activity of IgG autoantibodies from sera of patients with various types of lymphoproliferative diseases was
investigated. The association of DNA-hydrolyzing activity with the antibody (Ab) fraction has been proved by newly developed
affinity-capture assay. Study of abzyme incidence in blood tumors and systemic lupus erythematosis (SLE) revealed linkage
of anti-DNA Ab catalysts to mature B-cell tumors, and increased probability of DNA-abzymes formation on the background of
autoimmune manifestations. These data suggest possible similarity between mechanisms of abzyme formation in SLE and B-cell
lymphomas. A new mechanism of formation of DNA-specific catalytic Abs has been proposed based on the increased crossreactivity
of polyclonal DNA-abzymes to DNA-depleted nuclear matrix proteins. The possibility of the abzyme production as Ab to the energetically
destabilized ground state of the antigen has been discussed. Preliminary results were obtained that indicate the complement-independent
cytotoxicity of anti-DNA autoantibodies isolated from blood of patients with SLE and chronic lymphocytic leukemia. 相似文献
7.
Catalytic autoimmune antibodies from patients with antiphospholipid (aPL) antibodies were purified using histidyl-aminohexyl-sepharose gel. The sera were loaded on the columns equilibrated with 25 mM MOPS buffer pH 7.4 and the absorbed proteins were eluted by adding 0.2 M NaCl in the equilibrating buffer. Antibodies purity was evaluated by SDS-PAGE. The purified immunoglobulins G from patients with (aPL) sera by histidyl-aminohexyl-sepharose show DNA-degrading activity of the plasmid pUC19 DNA and catalytic activity in hydrolyzing the peptide substrate Pro-Phe-Arg-7-amido-4-methylcoumarin. 相似文献
8.
Frontispiece: Irreversible Denaturation of Proteins through Aluminum‐Induced Formation of Backbone Ring Structures 下载免费PDF全文
9.
The early stage of secondary structural conversion of amyloid beta (Aβ) to misfolded aggregations is a key feature of Alzheimer's disease (AD). Under normal physiological conditions, Aβ peptides can protect neurons from the toxicity of highly concentrated metals. However, they become toxic under certain conditions. Under conditions of excess iron, amyloid precursor proteins (APP) become overexpressed. This subsequently increases Aβ production. Experimental studies suggest that Aβ fibrillation (main-pathway) and amorphous (off-pathway) aggregate formations are two competitive pathways driven by factors such as metal binding, pH and temperature. In this study, we performed molecular dynamic (MD) simulations to examine the initial stage of conformational transformations of human Aβ (hAβ) and rat Aβ (rAβ) peptides in the presence of Fe2+ and Fe3+ ions. Our results demonstrated that Fe2+ and Fe3+ play key roles in Aβs folding and aggregation. Fe3+ had a greater effect than Fe2+on Aβs’ folding during intermolecular interactions and subsequently, had a greater effect in decreasing structural diversity. Fe2+ was observed to be more likely than Fe3+ to interact with nitrogen atoms from the residues of imidazole rings of His. rAβ peptides are more energetically favorable than hAβ for intermolecular interactions and amorphous aggregations. We concluded that most hAβ structures were energetically unfavorable. However, hAβs with intermolecular β-sheet formations in the C-terminal were energetically favorable. It is notable that Fe2+ can change the surface charge of hAβ. Furthermore, Fe3+ can promote C-terminal folding by binding to Glu22 and Ala42, and by forming stable β-sheet formations on the C-terminal. Fe3+ can also pause the main-pathway by inducing random aggregations. 相似文献
10.
Rocio Marilyn Caja Rivera 《Mathematical Methods in the Applied Sciences》2019,42(18):6810-6828
Vector‐borne diseases, such as leishmaniasis, dengue, malaria, and yellow fever, transmitted by microparasites show periodic fluctuations in their prevalence. The novelty of this research is to assess the relationship between the vector feeding preference for an infectious host and the annual seasonal transmission through a vector‐host mathematical model. For the first time, numerical simulations illustrate that by increasing the vector feeding preference value in the transmission dynamics, periodic fluctuations accentuate and the endemic equilibrium average increases in vector and host populations. Moreover, increasing the vector feeding preference value, the amplitude strengthens for the infectious host and vector populations. This periodic behavior shows a similar pattern with the Peruvian incidence data from 2000 to 2016 for Andean cutaneous leishmaniasis provided by the Ministry of Health of Peru (MINSA). In addition, using the Floquet theory, the time average method and the linear operator method provides for the first time that the basic reproduction number for a nonautonomous system depends explicitly on the vector feeding preference for the infectious host. The nonautonomous model system shows that is a threshold parameter for the local stability of the disease‐free periodic solution. Therefore, the vector feeding preference is an important factor that should be considered and attended to for future research. Public and veterinary health in Peru and other countries should consider the vector feeding preference for specific host to vector control. 相似文献