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H Komuro MB Valentine ST Rowe VJ Kidd S Makino GM Brodeur SL Cohn AT Look 《Canadian Metallurgical Quarterly》1998,33(11):1695-1698
Artificial illumination is an important factor in the management of layers. In this study, a new monochromatic light system was developed for egg layers. Prelaying pullets (Lohmann) were marked and housed in nine light and temperature control rooms (15 battery cages, 3 hens per cage; n = 45), divided into three light treatments: 0.1 and 0.01 W/m2 light intensity using light emitting diode (LED) lamps and 0.1 W/m2 using mini-fluorescent bulbs (PL) (control). In each of the LED rooms, three wavelengths were tested: 560 (n = 9), 660 (n = 9), 880 (n = 6), and 660 intermitted lighting (15 min light 45 min dark, 660IN) (n = 9). Birds were exposed to 12 h light and 12 h of darkness using PL lamps. At 21 wk of age, the light period was increased to 12.75 h by using 5.5 h of LED lamps and 7.25 of PL light source for Groups 1 and 2, the third group received 12.75 h of PL light. Until 28 wk of age, light hours increased by 0.5 h/w using LED light for Groups 1 and 2 and PL source for the third group, reaching 16 h of light at 28 wk of age. Egg production and feed consumption were recorded daily; egg components were recorded weekly for 10 mo. A significant reduction in egg production was observed in all 880nm groups; no differences in egg production and quality were found in the other groups. Feed consumption was significantly lower by 7% in all 0.01 W/m2 groups. We suggest that an important reduction in rearing costs of laying hens may be obtained by using this system. 相似文献
54.
E Zanelli TW Huizinga PA Guerne TL Vischer JM Tiercy W Verduyn GM Schreuder FC Breedveld RR de Vries 《Canadian Metallurgical Quarterly》1998,48(6):394-401
A family with 1 case of retinitis pigmentosa (III-1) and 2 cases of Oguchi's disease (III-2, 3) was examined in terms of electrophysiology as well as molecular biology. The proband (III-3), a 42-year-old female, and 2 older brothers (III-1, 2, aged 52 and 45 years) and 2 unaffected members in the same family participated in this study. Corrected visual acuities of the individuals with Oguchi's disease (III-2, 3) were 1.2. On funduscopy, blood vessels stood out in relief against a metallic-appearing background and a Mizuo-Nakamura phenomenon was evident. Full-field electroretinograms (ERGs) recorded from the proband were indicative of rod dystrophy, but results of other electrophysiological examinations (multifocal ERG, pattern ERG and visual-evoked cortical potential recordings) were within normal limits. Patient III-1 had corrected visual acuities of RE 20 cm/m.m. and LE 30 cm/n.d., severe chorioretinal atrophy in both fundi, and full-field ERG revealed rod-cone dystrophy. Mutation of the arrestin gene (1147de1A) was detected in all 3 patients. Visual function in each patient coincides with that of retinitis pigmentosa or Oguchi's disease, respectively. 相似文献
55.
CS Chen M Mrksich S Huang GM Whitesides DE Ingber 《Canadian Metallurgical Quarterly》1998,14(3):356-363
The control of cell position and function is a fundamental focus in the development of applications ranging from cellular biosensors to tissue engineering. Using microcontact printing of self-assembled monolayers (SAMs) of alkanethiolates on gold, we manufactured substrates that contained micrometer-scale islands of extracellular matrix (ECM) separated by nonadhesive regions such that the pattern of islands determined the distribution and position of bovine and human endothelial cells. In addition, the size and geometry of the islands were shown to control cell shape. Traditional approaches to modulate cell shape, either by attaching suspended cells to microbeads of different sizes or by plating cells on substrates coated with different densities of ECM, suggested that cell shape may play an important role in control of apoptosis as well as growth. Data are presented which show how micropatterned substrates were used to definitively test this hypothesis. Progressively restricting bovine and human endothelial cell extension by culturing cells on smaller and smaller micropatterned adhesive islands regulated a transition from growth to apoptosis on a single continuum of cell spreading, thus confirming the central role of cell shape in cell function. The micropatterning technology is therefore essential not only for construction of biosurface devices but also for the investigation of the fundamental biology of cell-ECM interactions. 相似文献
56.
GM Ginsberg T Schlesinger A Ben-Shlomo A Kushilevsky M Margaliot M Oren M Finkleman A Friedman M Handlesman B Lev 《Canadian Metallurgical Quarterly》1998,71(844):406-412
In Israel the diffusion of rare earth screen technology has been limited. These screens could halve the radiation dose to the patient from diagnostic X-ray radiography, with little managerial effort and without being detrimental to the quality of the diagnostic image. We estimated the total effective dose from diagnostic film radiography capable of reduction by the use of rare earth screens, based on the number of hospital and ambulatory diagnostic X-ray procedures. This number was multiplied by the computed radiation dose per body site for a series of diagnostic procedures. The annual dose was approximately 0.53 mSv per head, approximately half of which could be averted by the introduction of rare earth screen technology. Based on a fatality risk of 3% Sv-1, it is estimated that the adoption of rare earth screen technology might reduce the annual incidence of cancer by some 93 cases, half of which would be fatal after an average latency period of 18.4 years. The cost of purchasing rare earth screens on a nationwide basis is approximately $3.0 million. This cost is outweighed by a saving of $9.6 million in X-ray tube replacement costs over the period 1997-2006. Government legislation enforcing the use of rare earth screens is essential, because of the lack of prestige associated with acquiring rare earth technology, as well as institutional reluctance to accept the external benefits of reduced morbidity and mortality and/or to extend budgetary time horizons. 相似文献
57.
OBJECTIVE: The objective of this study was to assess somatic and inherited androgen receptor gene mutations in families with only one affected individual. METHODS: Molecular genetic analysis of the androgen receptor gene in DNA derived from blood leukocytes from 30 families with single-strand conformation analysis, direct sequencing, and restriction fragment analysis was performed. RESULTS: In 22 families the mothers and all investigated grandmothers were heterozygous carriers. However, within the sisters and aunts, both heterozygous carriers and noncarriers were present. In eight families a de novo mutation was characterized. In three of these patients indication for somatic mosaicism was found. CONCLUSIONS: De novo mutations occur at a high rate within the androgen receptor gene (8 of 30 = 26.7%); a high proportion (3 of 8) arise after the zygote stage. Thus only direct analysis of the underlying mutation of the androgen receptor gene in the proband and his or her family can provide the basis for genetic counseling. 相似文献
58.
59.
RL Richards M Rao NM Wassef GM Glenn SW Rothwell CR Alving 《Canadian Metallurgical Quarterly》1998,66(6):2859-2865
Encapsulation of soluble protein antigens in liposomes was previously shown to result in processing of antigen via the major histocompatibility complex class I pathway, as evidenced by costaining of the trans-Golgi region of murine bone marrow-derived macrophages (BMs) by fluorophore-labeled liposomal antigen and by a trans-Golgi-specific fluorescent lipid. Evidence is presented here that free or liposome-encapsulated RTS,S, a particulate malaria antigen consisting of hepatitis B particles coexpressed with epitopes from the Plasmodium falciparum circumsporozoite protein, also was localized in the trans-Golgi after incubation with BMs, suggesting processing by the class I pathway. An in vivo cytotoxic T-lymphocyte (CTL) response was detected, however, only after immunization with RTS,S encapsulated in liposomes containing lipid A and not after immunization with free RTS,S or with RTS,S encapsulated in liposomes lacking lipid A. Therefore, intracellular delivery of antigen containing CTL epitopes to the Golgi of BMs does not necessarily result in a CTL response in vivo unless an additional adjuvant, such as liposomes containing lipid A, is utilized. Encapsulation of RTS,S in liposomes containing monophosphoryl lipid A (MPL) resulted in a dose-dependent enhancement of the NANP-specific immunoglobulin G (IgG) antibody response compared to that of free RTS,S. The IgG1 and IgG2a subclasses predominated after immunization with RTS,S encapsulated in liposomes containing MPL. These results demonstrate that encapsulation of a lipid-containing particulate antigen, such as RTS, S, in liposomes containing lipid A can enhance both humoral and cellular immune responses. 相似文献
60.
A G protein gamma subunit-like domain shared between RGS11 and other RGS proteins specifies binding to Gbeta5 subunits 总被引:1,自引:0,他引:1
BE Snow AM Krumins GM Brothers SF Lee MA Wall S Chung J Mangion S Arya AG Gilman DP Siderovski 《Canadian Metallurgical Quarterly》1998,95(22):13307-13312
Regulators of G protein signaling (RGS) proteins act as GTPase-activating proteins (GAPs) toward the alpha subunits of heterotrimeric, signal-transducing G proteins. RGS11 contains a G protein gamma subunit-like (GGL) domain between its Dishevelled/Egl-10/Pleckstrin and RGS domains. GGL domains are also found in RGS6, RGS7, RGS9, and the Caenorhabditis elegans protein EGL-10. Coexpression of RGS11 with different Gbeta subunits reveals specific interaction between RGS11 and Gbeta5. The expression of mRNA for RGS11 and Gbeta5 in human tissues overlaps. The Gbeta5/RGS11 heterodimer acts as a GAP on Galphao, apparently selectively. RGS proteins that contain GGL domains appear to act as GAPs for Galpha proteins and form complexes with specific Gbeta subunits, adding to the combinatorial complexity of G protein-mediated signaling pathways. 相似文献