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1.
H. Ono R. Akiyama Y. Sakamoto J. T. Pearson H. Tazawa 《Medical & biological engineering & computing》1997,35(4):431-435
As an avian embryo grows within a eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat.
A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure
the cardiogenic ballistic movement of the egg or ballistocardiogram. (BCG). In this context, there is interest in using an
electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG
measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet
is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system.
Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs,
indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of
the velocity of egg movements. 相似文献
2.
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
3.
R. Gagnemo-Persson A. Samuelsson R. Håkanson P. Persson 《Calcified tissue international》1997,61(3):210-215
Treatment with omeprazole, a long-acting proton pump inhibitor of acid secretion, induces hypergastrinemia. In chickens,
omeprazole induces growth not only of the acid-producing mucosa (probably reflecting the trophic action of gastrin), but also
of the parathyroid glands (hypertrophy + hyperplasia), while suppressing bone density and body weight gain without affecting
blood calcium. The first part of the present study was concerned with the effect of omeprazole, ergocalciferol (vitamin D2), and restricted food intake on the gene expression of parathyroid hormone (PTH) in the parathyroid glands of the chicken.
Chickens were treated with omeprazole (400 μmol/kg/day, I.M.), food restriction, omeprazole + food restriction, ergocalciferol
(250 000 IU/kg/day, S.C.), or ergocalciferol + omeprazole for 5 weeks. The weight gain of the chickens was monitored, and
the weights of the parathyroid glands and femurs were determined at sacrifice. PTH mRNA in the parathyroid glands was analyzed
by Northern blot. The second part of the study examined the effect of 3 weeks of continuous gastrin infusion (chicken gastrin
20–36, 5 nmol/kg/hour, S.C.) on the expression of PTH mRNA in the parathyroid glands. Omeprazole reduced the body weight and
femur density (ash weight per volume) while greatly increasing the weight of the parathyroid glands and the PTH gene expression.
Food restriction alone and ergocalciferol alone (at a dose that raised blood Ca2+) were without effect, but food restriction greatly enhanced the omeprazole-evoked increase in parathyroid gland weight and
PTH gene expression. Gastrin increased the weight of the parathyroid glands and reproduced the effect of omeprazole on PTH
gene expression. Hence, it seems likely that the effect of omeprazole reflects the ensuing hypergastrinemia.
Received: 6 August 1996 / Accepted: 23 April 1997 相似文献
4.
目的观察鸡精用于产后乳汁分泌的临床效果。方法产后每日早晚各服白兰氏鸡精70ml,共服3d,并与对照组、中药材催乳组对比。结果鸡精有促进早泌乳与增加泌乳量的作用。结论鸡精用于产妇有滋养身体,恢复产妇体力,促进早泌乳和增加泌乳量的作用,且饮用方便,效果好,无不良反应。 相似文献
5.
Toda Takayoshi Leszczynski Dennis McGibbon William H. Kummerow Fred A. 《Virchows Archiv : an international journal of pathology》1980,388(2):123-135
Summary The effects of hereditary hyperlipidemia on coronary artery atherosclerosis were studied in 77 White Leghorn (DeKalb strain) chickens ranging from 4 to 13 months in age. After pubescence, the plasma levels of triglyceride and cholesterol in non-laying hens ranged 2- to 3-fold and 2- to 7-fold higher compared to layers. Serial sectioning revealed that most lesions were found in the proximal portions of both the left and right coronary arteries. Ultrastructurally, lesions in the roosters contained no foam cells, whereas some foam cells and small amounts of stainable lipid were observed in the thickened intima of layers. Half of the non-layers had stenotic lesions characterized by many foam cells, necrotic foci, and heavy stromal lipid deposits. Continuous permeation of excess plasma lipids into the arterial wall appeared to be an important factor in the development of coronary lesions. 相似文献
6.
7.
目的探讨不同性质高压静电场对雏鸡免疫器官细胞免疫变化的影响。方法用组织化学染色及细胞培养技术和MTT测定法对高压静电场照射雏鸡免疫器官的T细胞数量及其对ConA增殖功能的动态变化进行了检测。结果高压正静电场照射雏鸡免疫器官的T细胞数量及其增殖功能明显高于高压负静电场照射雏鸡和对照雏鸡;而高压负静电场照射雏鸡免疫器官的上述各项检测指标均不同程度的低于对照雏鸡。结论高压正静电场照射对雏鸡免疫器官的细胞免疫功能有促进作用,而高压负静电场照射可使雏鸡免疫器官的细胞免疫功能降低或减弱。 相似文献
8.
The presence and distribution patterns of ghrelin, a gastric acylated peptide, were studied in the entire gastrointestinal tract of the chicken (Gallus domesticus) using the peroxidase-antiperoxidase immunohistochemical method, western blot analysis and a specific antibody against the C-terminal region of rat ghrelin. Ghrelin-immunopositive cells were observed in the mucosal layer of all segments examined. The largest numbers of ghrelin-positive cells were located at the base of lobuli of the proventriculus gland, along villi of the intestines and in crypts of the duodenum. Lower numbers of ghrelin-immunostained cells were located in crypts of jejunum and ileum and only few ghrelin-immunostained cells were detected at the base of crypts of the large intestine. Closed and open types of cells were observed in all segments. Western blot analysis confirmed the presence of ghrelin-like protein in the entire chicken gastrointestinal tract. The anatomical distribution patterns and the morphological characteristics of chicken ghrelin-positive cells suggest that they are endocrine cells. Furthermore, it is concluded that ghrelin shows a high degree of preservation during evolution from non-mammalian vertebrates to mammals. 相似文献
9.
鸡干扰素-γ抗球虫作用研究进展 总被引:3,自引:0,他引:3
干扰素-γ(IFN-γ)是一种重要的细胞因子,主要由T细胞、NK细胞产生,具有广谱抗病毒、抗肿瘤和双向免疫调节作用。重组鸡干扰素-γ(rChIFN-γ)已被证明与鸡球虫病的免疫有关。本文就鸡干扰素-γ(ChIFN-γ)的生物学特性及其抗球虫作用的研究进展作一综述。 相似文献
10.
Margarita Gallego Emilio del Cacho Agustin Zapata Jose Antonio Bascuas 《Anatomical record (Hoboken, N.J. : 2007)》1995,242(2):220-224
Background: There is a need to identify the follicular dendritic cells (FDC) of the chicken spleen at the ultrastructural level during a secondary immune response. Methods: The cells were identified after intravenous priming BSA and boosting with biotinylated BSA conjugated to colloidal gold particles. Monoclonal antibodies raised specifically either to chicken IgG or IgM were used to characterize these immune complex-trapping cells. Results: The FDC had an irregular morphology which varied through time, supporting the existence of two types of FDC in the chicken spleen, one showing filiform cell processes, the other provided with beaded dendrites. When the filiform dendrites were observed, the FDC bound the antigen on their surfaces. These dendrites showed an intrincate convoluted configuration, forming tightly wrapped networks near the cell body. The networks had the same features as those described in mammals as antigen retaining reticulum (ARR). In chickens, the ARR, which represents sites of antigen localization on FDC, reached maximum development on day 5 after the second injection of BSA and had disappeared by day 8. At this time FDC had beaded dendrites. Conclusions: Antigen is retained on FDC in the chicken spleen for long periods of time. © 1995 Wiley-Liss, Inc. 相似文献