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Infants born of allergic mothers but normal fathers, who had eczema and who were fed cows' milk, had a significantly greater incidence of asthma (P less than 0.001) than infants with a similar history but who were breast-fed. An analysis of all breast-fed infants in the study showed that they were less likely to develop asthma than those who were bottle-fed (P less than 0.06). There was a lower incidence of allergy in infants born of families with allergic mothers and normal fathers, than in families in which both parents were allergic (P less than 0.02). In skin tests of both breast or bottle-fed babies, the two most common allergens eliciting reactions were egg and cat dander.  相似文献   
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This study was carried out to investigate the effect of various application methods for a chlortetracycline (CTC) and oxytetracycline (OTC) combination (0.9 mg of each per kg of meat) on the shelf‐life of lamb during storage. Twelve‐fat, tail type Akkaraman male lambs were divided into four groups by a “block assignment method”. The first group was kept as the control (C), while the others were subjected to applications as “injection antemortem (A)”, “immersion (I)” and “spraying (S)”. Meat samples were stored at 4C for 12 days. The specimens from loin and leg were tested for microbial, chemical and physical criteria. The results indicated that a CTC and OTC combination extended the shelf‐life of lamb at 4C in an increasing order from A to S to 1. The last one may be used to extend the shelf‐life of lamb during refrigerated storage.  相似文献   
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Twenty-five male Sprague-Dawley rats were trained in five two-lever operant chambers on a DRL-15 sec schedule of positive food reinforcement to discriminate 10 mg/kg cocaine from 1 ml/kg saline. Following acquistions of discrimination a counterbalanced design of extinction tests was performed before and after repeated administration of 20 mg/kg cocaine or saline (three times a day at five hr intervals for seven days). The extinction tests consisted of testing responses of animals following 1 ml/kg saline, 2.5 mg/kg cocaine, or 5 mg/kg cocaine. The results showed no significant difference in animals' level choice before and after repeated injection with saline. However, the percent cocaine lever choice with the two doses of cocaine was lower after repeated administration of cocaine than before the repeated injections. This indicates tolerance developed to the discriminative stimulus properties of cocaine.  相似文献   
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Formation and development of the Navy medical service started back in the 30th of the XXth century. In 1938 they created a naval and marine sanitary disciplines' Chair which was successively a component of the Navy faculty of the 1st Leningrad Institute of Medicine, Naval Academy of Medicine and from 1956--a part of the Academy of Military Medicine. For 60 years of its existence, the Chair has implemented nearly 350 fundamental research projects, more than 50 directives, edited some 60 textbooks and manuals and over 60 theses were defended. Its students were 59 courses of doctors for ships and navy units and above 300 administrators.  相似文献   
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Different delivery vehicles may target to different antigen presenting cells (APC) because of their composition, size and/or physical properties. In this study, we examined the priming of cytotoxic T lymphocyte (CTL) responses to a soluble exogenous protein in vivo, using various delivery vehicles. In addition, we determined the role of macrophages as APC in vivo for each of these delivery vehicles by comparing the induction of antigen-specific CTL and serum antibodies in normal and macrophage-depleted mice. Influenza A virus-derived virosomes, liposomes and monophosphoryl lipid A/squalene (MPLSQ) efficiently induced antigen-specific CTL as well as antibody responses, of which virosomes proved to be the most efficient inducers. In mice that were immunized with cell-associated antigen, strong CTL responses but no antigen-specific antibodies were detectable, while aluminium hydroxide and aluminium phosphate elicited antigen-specific antibodies but no CTL responses. Elimination of macrophages in vivo before immunization abrogated CTL responses induced with liposomes and MPL/SQ, but did not affect induction of antigen-specific CTL with virosomes or cell-associated antigen. Importantly, serum antibody levels were not altered after macrophage depletion, regardless of the delivery vehicle used, suggesting that in the absence of macrophages, other APC may phagocytose the exogenous antigens for major histocompatibility complex (MHC) class II processing and presentation. These results suggest that soluble exogenous antigens delivered in different carrier systems may be processed differently by different APC in vivo for MHC class I- or class II-restricted presentation.  相似文献   
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The common chemical features of oligopeptide releasing-hormones and release inhibiting hormones were investigated with the aid of computer methods. 339 regulatory molecules of such type have been extracted out of data from computer bank EROP-Moscow. They contain from 2 to 47 amino acid residues and their sequences include short sites, which play apparently a decisive role in realization of interactions with the receptors. The analysis of chemical radicals shows that all liberins and statins contain positively charged group and cyclic radical of some amino acids or hydrophobic group. Results of this study indicate that the most chemical radicals of hormones are open for the interaction with potential receptors of target-cells. The mechanism of hormone ligand and receptors binding and conceivable role of amino acid and neurotransmitter radicals in hormonal properties of liberins and statins is discussed.  相似文献   
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An enhanced method for determining cardiac output using Doppler color flow imaging techniques to measure mitral orifice diameter was developed and validated in an experimental model and in clinical patients. In an in vitro circuit model, color jet width correlated well with actual orifice dimension from 12 to 24 mm (r = 0.99). In the clinical application, mitral valve area was calculated as a X b X pi/4 where a and b represent the width of the color flow stream in the mitral orifice just distal to the annulus in apical long-axis (short-diameter) and 4-chamber (90 degrees rotated, long-diameter) views, respectively. Cardiac output was then computed as the product of mitral valve area and time-velocity integral of transmitral flow from the same site. Cardiac output was also measured by thermodilution and conventional echocardiographic methods using diameters and time-velocity integrals from the left ventricular outflow tract. In 30 patients with nonvalvular heart disease, cardiac output measured by thermodilution ranged from 3.40 to 8.40 L/min. Cardiac output was determined in 28 of 30 patients (93%) by the Doppler color flow imaging technique; it ranged from 3.00 to 8.36 L/min and correlated well with thermodilution: y = 0.90x + 0.63, r = 0.91. Cardiac output was determined in 24 of 30 patients by the conventional left ventricular outflow method (80%). The cardiac output measured by the conventional method correlated less closely with thermodilution (r = 0.84), although there was no statistical difference in correlation coefficiencies between the 2 methods. These results indicate that the Doppler color flow imaging technique can be used to enhance the determination of cardiac output by echocardiography, particularly when the conventional method has resulted in technically inadequate recordings.  相似文献   
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