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1.
Laying hens are very efficient producers of antibodies and provide an interesting alternative for large-scale production of specific antibodies. These antibodies also have biochemical advantages over mammalian antibodies (e.g. rabbit antibodies) that can be used to improve immunoassays where antibodies are used. The concentration of IgY in egg yolk is an important production parameter. The purpose of this study was to investigate the genetic variation of IgY levels in egg yolk. We have compared IgY concentrations in egg yolks from two lines, selected for egg production traits at the Swedish University for Agricultural Sciences (Single Comb White Leghorn and Rhode Island Red) and a cross between the two lines (SLU-1392). Single Comb White Leghorns have the highest mean concentration of yolk IgY, 2.21 mg ml-1 compared to SLU-1392 1.95 mg ml-1 and Rhode Island Red 1.68 mg ml-1. The cross thus had an intermediate IgY concentration in relation two the two other lines. There were great differences between individual animals within each line. Our results indicate that it should be possible to increase yolk antibody production by using a high producing chicken line and by genetic selection within the line. We found three individuals with very low yolk IgY concentrations among the Rhode Island Red hens. Newly hatched chickens with limited amounts of IgY from the hen may be more susceptible to infections.  相似文献   
2.
The purpose of this study was to compare the stress-response-dampening (SRD) effect of alcohol in hostile and nonhostile men based on a combined score of four subscales of the Cook-Medley Hostility Scale . Subjects were 72 male social drinkers. Subjects' cardiac interbeat-interval, and systolic and diastolic blood pressure reactivity to a situational stressor were measured following the consumption of either alcohol, no alcohol, or an active placebo beverage. Results demonstrated that hostile men evinced lower heart rate and systolic blood pressure (SBP) reactivity to the stressor when given alcohol, compared with intoxicated nonhostile subjects, and lower reactivity relative to all other groups, with the exception of SBP in the nonhostile controls. These results allow for speculation that hostile men may be more likely than controls to experience possible SRD effects of alcohol and thus, perhaps, be predisposed to increased alcohol consumption when under stress.  相似文献   
3.
Two ways of rate control for diaphragm pacing are proposed. One is rate control using only the patients' body temperature (method I). The other is rate control by both the patients' heart rate and body temperature (method II). To test the effectiveness of these methods, a diaphragm pacemaker which can be controlled by both heart rate and body temperature has been developed. It was applied to nine mongrel dogs. The pacing rate is controlled by atrial blood temperature (method I) or by both heart rate and temperature (method II). The animal's metabolism was elevated by the administration of a pyrogenic drug. It was found that method I is not suited to rapid changes in metabolism; however, it is useful in extreme metabolic elevation. An animal's metabolism was supported by using method II in all ranges of metabolism. This method proved more effective than method I for rate-responsive diaphragm pacing.  相似文献   
4.
Summary During strenuous exercise lactic acid (LA) appears in the blood as a result of anaerobic metabolism. The rate at which this LA was removed from the blood after exercise was seen to increase to a maximum with a certain level of post exercise activity. This maximum rate of removal of LA appears to be at approximately 40% of the individual's maximum oxygen uptake when the exercise is performed on a bicycle ergometer.  相似文献   
5.
Abstract

This paper presents the hardware implementation of low delay, power-efficient, rate-adaptive dual-chamber pacemaker (RDPM) using a piezoelectric sensor. Rate adaptive pacemaker has the ability to sense the patient’s activity by means of some special sensors and it controls the pacing rate according to the patient’s activity. Ideally, there should be no delay between sensing and the subsequent pacing operation performed by the pacemaker. However, delay in the responses of various components in the circuitry produces an accumulative delay effect in any practical circuit. Physical activity and the physiological needs of the patient can be easily adapted by the rate-responsive pacemakers using a wide range of sensor information. The piezo-electric sensor recognises the pressure on human muscles because of physical activity and converts it to an electrical signal, which is received by the pulse generator of the pacemaker. When the patient is in the rest mode, the heart rate is the only parameter that is to be detected by the pacemaker. Thus, the heart rate and the physical activity both are the inevitable parameters for the design of RDPM. Performance analysis of the proposed RDPM shows a significant reduction in the delay between sensing and pacing. Device utility analysis shows that the proposed design not only requires lesser memory but also reduces the number of components on the chip. Therefore, it becomes very clear that the proposed pacemaker design will consume much lesser power.  相似文献   
6.
Summary Techniques have been developed for collection of urine in embryonic and newly hatched chickens for the purpose of studying the development of renal function.The reliability of EDTA-51Cr as a substitute for inulin-14C in the determination of GFR was studied. Since inulin and EDTA-51Cr clearances in the hatched chicken averaged 1.61±0.23 (S.E.) ml/min per kg body weight and 1.58±0.27 ml/min per kg body weight, respectively, EDTA-51Cr clearance was considered a suitable measure of GFR.GFR increased significantly in the first few days after hatching. Filtration rate was 0.068±0.008 (S.E.) ml/min per g kidney weight in the embryo and increased to 0.148±0.008 ml/min per g shortly after hatching. By nine days after hatching GFR had risen to 0.290±0.015 ml/min per g, a value comparable to that reported for the adult.Clearances of sodium, potassium, chloride and total osmolyte also increased with age. When these clearances were corrected for changing glomerular filtration rates the embryonic chicks were found to excrete a greater percentage of the filtered load. These results show that adult levels of glomerulo-tubular balance are not attained until after hatching.A preliminary report of this work has already been published [3].  相似文献   
7.
Summary Single nephron filtration rates of superficial and juxtamedullary nephrons were determined in high and low sodium rats. Single nephron GFR was calculated from TF/P inulin and tubular flow rate in superficial nephrons and single juxtamedullary GFR from corresponding data in long loops of Henle. In low sodium rats superficial nephron GFR was 23.5±6.4 (SD)×10–6 ml/min×g KW, juxtamedullary nephron GFR was 58.2±13.6 and total kidney GFR (C In) was 0.94±0.16 ml/min×g KW. Using these single nephron values, total kidney GFR and a total number of 30,000 glomeruli per kidney, the number of superficial and juxtamedullary glomeruli was calculated to be 23,267 and 6,733, respectively. During high sodium diet superficial nephron GFR increased to 38.1±11.3 and single juxtamedullary GFR decreased to 16.5±6.6, total kidney GFR increasing to 1.01±0.24. Calculation again revealed the same distribution of the two nephron types. End-proximal TF/P inulin in superficial nephrons was 2.36±0.36 in low sodium and 2.31±0.28 in high sodium rats. Loops of Henle TF/P inulin and intratubular flow rate were inversely related: the highest TF/P inulin values and lowest intratubular flow rates were found in the descending limb. These data quantify the distribution of superficial and juxtamedullary nephrons on a functional basis and suggest a mechanism by which the kidney adjusts sodium excretion by altering the contribution of each nephron type to total kidney GFR.Supported by the Deutsche Forschungsgemeinschaft and the U.S. Department of the Army, through its European Research Office.  相似文献   
8.
The contribution of bone loss to postmenopausal osteoporosis   总被引:14,自引:6,他引:8  
We have addressed the relative importance of peak bone mass and subsequent rate of loss in determining postmenopausal women's bone mass in old age, by examining longitudinal measurements of radial mid-shaft bone mass on various samples of healthy white postmenopausal women. Using both the variance estimate of age-specific rates of bone loss and the population variance in bone mass, we determined that rates of loss could contribute importantly to future bone mass. However, since we found a small negative correlation between initial bone mass and rate of loss, it was necessary to estimate the effect of bone loss as the complement of the contribution of initial bone mass. We found that the influence of bone loss (relative to initial bone mass) increases as the women age, such that by about age 70, the contribution of initial bone mass and rate of loss approached equality. However, estimated rates of bone loss were not very stable over time, so it was difficult to identify long-term fast-losers. We conclude that the rate of postmenopausal bone loss is an important contributor to osteoporosis at old age, but it is difficult to identify long-term fast-losers, thereby reducing the clinical value of assessments of rates of change in bone mass early in the postmenopause.  相似文献   
9.
Summary Kinetics of antagonist-induced decrease of histamine-H1 receptor-mediated steady-state responses in isolated rabbit arteries were studied in the presence of histamine-H2 receptor antagonist famotidine. Data were fitted using a model which describes competition kinetics at the receptor level. Estimated rate and equilibrium constants were evaluated for their dependence on tissue, agonist and antagonist concentrations, using (+)-brompheniramine as antagonist. In large arteries (thoracic and arcus aorta), rate constants were observed to be modified by agonist and/or antagonist concentrations, suggesting a diffusion-controlled process. In relatively small (common carotid and iliac) arteries, estimated equilibrium constants (and consequently the rate constants) were found to diverge despite the invariance of equilibration times between arteries, leading us to include the effects of spare receptors in our evaluation. A model describing the effects of receptor reserve on the estimated equilibrium dissociation constant was developed and stimulated and the results then compared with those that had been experimentally estimated. The reserve hypothesis was experimentally verified in common iliac artery (where EC50 K A) using the irreversible antagonist phenoxybenzamine. A rationalized rule for the optimization of experimental design for in-vitro disequilibrium-competition experiments was proposed. Common carotic artery was found to be favorable for the present design in view of its reserve properties. In addition, competition reaction seems to be the rate-determining step in this artery. Rate and equilibrium constants of mepyramine, (+)-brompheniramine, diphenhydramine and antazoline were therefore determined in the common carotid artery and were compared with those obtained from independent experiments. Results suggest that the estimated parameters reflect drug-receptor interaction.This work constitutes a part of the PhD thesis of H. O. Onaran Send offprint requests to T. A. Bökesoy at the above address  相似文献   
10.
目的研究多方式下延续性护理对慢性非萎缩性胃炎(CNAG)患者出院后健康素养、生活质量和复诊率的影响。方法选择本院2018年10月至2019年6月诊治的94例CNAG患者作为研究对象,采用信封随机法将患者均分为延续组和常规组,各47例,前者给予多方式下延续性护理,后者给予常规护理。均干预6个月.,比较两组患者健康素养、生活质量以及复诊率。结果干预后两组患者健康素养分值均较干预前显著上升.,延续组患者上升幅度较常规组更显著(P<005);延续组.患者生理功能、生理职能、活力、精神健康、躯体疼痛、总体健康评分均显著高于常.规组(P<005),而情感职能、社会功能与常规组相比差异不显著(P>005);延续组患者复诊率显著高于常规组,但再就诊率与常规组相比差异不显著(P>005)。结论多方式延续性护理可有效提高CNAG患者的健康素养和生活质量,提高复诊率。  相似文献   
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