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51.
Left ventricular myocardial contractility was found essential in dynamics of clinical IHD picture in patients on rehabilitation treatment at low mountain resorts. All the patients have previously undergone surgical myocardial revascularization. Patients with normal left ventricular myocardial contractility benefited most of all.  相似文献   
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Alfalfa (Medicago sativa L.), low-endophyte (< 5%) tall fescue (Festuca arundinacea Schreb.), and caucasian bluestem (Bothriochloa caucasica [Trin.] C.E. Hubbard) were fed as chopped hay to six Arabian geldings (BW 441 kg; SE 2) in intake and digestibility experiments to determine nutritional value for horses at maintenance. Each experimental design was a replicated Latin square. Alfalfa was higher in DM and CP digestibility, IVDMD, apparent absorption of Ca, K, and S, and voluntary intake than the grasses (P < .05). Caucasian bluestem was higher in Zn but was lower in CP, TNC, Mg, P, K, S, and Cu concentrations than tall fescue. Crude protein digestibility and apparent absorption of Mg, K, and S were higher (P < .05) for tall fescue than for caucasian bluestem. Geldings fed alfalfa for ad libitum intake had higher serum concentrations of vitamin A, blood urea nitrogen, P, S, and Cu than geldings fed grass hays. Serum Zn was higher (P < .05), whole blood Se tended to be higher (P < .06), and BUN was lower (P < .05) in geldings fed caucasian bluestem than in those fed tall fescue. All forages met requirements for CP, Ca, Mg, K, and Fe when fed for ad libitum intake but were deficient in Cu for horses at maintenance. Caucasian bluestem was borderline in CP and was deficient in P but was the only forage that met the Zn requirement for the horses. Based on these results, caucasian bluestem could be a useful hay for horses but may require supplementation of CP and P.  相似文献   
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Antibodies (Abs) hydrolyzing proteins, DNA, and RNA are detected in the blood of patients with various autoimmune diseases. In the present work, homogeneous preparations of IgG Abs from the blood of the healthy donors as well as patients with A, B, C, and delta types of viral hepatitis, influenza, pneumonia, tuberculosis, tonsillitis, duodenal ulcer, and some types of cancer were purified. For the first time, the fraction of IgG and its Fab fragments of patients with viral hepatitis were shown to have high DNA- and RNA-hydrolyzing activity. In case of Abs from the healthy donors and patients with other diseases, high activity of Abs was not detected. The data obtained by various methods indicate that the activity of hepatitis Abs is an intrinsic property of the immunoglobulins. The relative rates of hydrolysis of cCMP, poly(U), poly(A), poly(C), and tRNA(Phe) by hepatitis Abs were compared with those of RNase A and other RNases from human blood. Significant differences in activities of Abs and nucleases in hydrolysis of model substrates were demonstrated. Thus, catalytically active Abs can appear in the blood of patients not only with autoimmune disorders, but with viral diseases as well.  相似文献   
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The isolation of single-stranded (ss) phagemid DNA using standard protocols often results in impure preparations, which contain undesirable quantities of chromosomal and/or double-stranded (ds) phagemid DNA. Here we report a simple and efficient method for elimination of virtually all dsDNA by incubation of phagemid viral particles with deoxyribonuclease I. In addition to analyzing the ratio of linear-to-circular topological forms of ssDNA after deoxyribonuclease I treatment, we verified that no decrease in transformation efficiency occurred and demonstrated that ssDNA molecules covered by capsid proteins remained intact following such treatment.  相似文献   
57.
The Dama de Elche (4th–5th century B.C.), an emblematic piece of the ancient Iberian culture, was first sculpted in fossiliferous limestone of Tertiary Age. In this first systematic study, two classic pigments have been identified: Egyptian blue, prepared with a potassium flux, and natural vermilion applied over a preparation layer of gypsum, mixed with calcium carbonate, that migrated and recrystallized on the polychrome surface of the bust, process favoured by the change suffered after its disinterment. No anachronisms have been found on the identified polychromy, the existing coating surface nor any other element that might suggest it to be a modern forgery.
Résumé La Dama de Eleche, sculpture emblématique de la culture ibère, fut taillée en pierre calcaire avec des fossiles de l'ère tertiaire. Dans cette première investigation systématique, on a identifié deux pigments classiques: le bleu égyptien, préparé avec un fondant potassique, et le vermillon naturel, appliqués sur une couche de préparation en platre, mélangé avec de la chaux, qui a migré et a recristallisé sur la surface polychrome du buste. Ce procédé a été aidé pour les changements subis après son déterrement. On n'a pas trouvé d'anachronisme en ce qui concerne les pigments et la couche de préparation. Aucun élément ne permet, de déduire que la sculpture puisse être un faux moderne.


Editorial note The “Eduardo Torroja” Institute (CSIC) is a RILEM Titular Member. Dra. M.P. de Luxán participates in RILEM TCs CUA ‘Concrete use of additions’ and RHM, ‘Repair mortars for historic buildings’. Dr. F. Dorrego also participates in RILEM TC RHM.  相似文献   
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Lung cancer is the most common and most fatal cancer worldwide. Thus, improving early diagnosis and therapy is necessary. Previously, gadolinium‐based ultra‐small rigid platforms (USRPs) were developed to serve as multimodal imaging probes and as radiosensitizing agents. In addition, it was demonstrated that USRPs can be detected in the lungs using ultrashort echo‐time magnetic resonance imaging (UTE‐MRI) and fluorescence imaging after intrapulmonary administration in healthy animals. The goal of the present study is to evaluate their theranostic properties in mice with bioluminescent orthotopic lung cancer, after intrapulmonary nebulization or conventional intravenous administration. It is found that lung tumors can be detected non‐invasively using fluorescence tomography or UTE‐MRI after nebulization of USRPs, and this is confirmed by histological analysis of the lung sections. The deposition of USRPs around the tumor nodules is sufficient to generate a radiosensitizing effect when the mice are subjected to a single dose of 10 Gy conventional radiation one day after inhalation (mean survival time of 112 days versus 77 days for irradiated mice without USRPs treatment). No apparent systemic toxicity or induction of inflammation is observed. These results demonstrate the theranostic properties of USRPs for the multimodal detection of lung tumors and improved radiotherapy after nebulization.  相似文献   
59.
The preparation of ultrasmall and rigid platforms (USRPs) that are covalently coupled to macrocycle‐based, calcium‐responsive/smart contrast agents (SCAs), and the initial in vitro and in vivo validation of the resulting nanosized probes (SCA‐USRPs) by means of magnetic resonance imaging (MRI) is reported. The synthetic procedure is robust, allowing preparation of the SCA‐USRPs on a multigram scale. The resulting platforms display the desired MRI activity—i.e., longitudinal relaxivity increases almost twice at 7 T magnetic field strength upon saturation with Ca2+. Cell viability is probed with the MTT assay using HEK‐293 cells, which show good tolerance for lower contrast agent concentrations over longer periods of time. On intravenous administration of SCA‐USRPs in living mice, MRI studies indicate their rapid accumulation in the renal pelvis and parenchyma. Importantly, the MRI signal increases in both kidney compartments when CaCl2 is also administrated. Laser‐induced breakdown spectroscopy experiments confirm accumulation of SCA‐USRPs in the renal cortex. To the best of our knowledge, these are the first studies which demonstrate calcium‐sensitive MRI signal changes in vivo. Continuing contrast agent and MRI protocol optimizations should lead to wider application of these responsive probes and development of superior functional methods for monitoring calcium‐dependent physiological and pathological processes in a dynamic manner.  相似文献   
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