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1.
The crossreactivity of mouse monoclonal antibodies (MoAbs) (Tab. I) prepared against human HLA-DR and HLA-DP antigens was studied in various bovine cells: lymphocytes from lymph nodes and peripheral blood, adherent (B) and nonadherent (T) lymphocytes, monocytes, granulocytes and platelets. In the immunofluorescence test, MoAbs Bra13, Bra14, Bra20, Bra22, Bra30, Bra70, HL-38 reacted with bovine B lymphocytes and monocytes, but not with other tested cells (Tab. III, IV). These antibodies, except Bra22, were positive with B lymphocytes in the complement dependent cytotoxic test (Tab. II). The similarity of the bovine antigens and HLA-DR antigens determined by used MoAbs was also proved by immunoblotting. Monoclonal antibodies Bra38 and BraFB6 did not react with the bovine cells and separated antigens. The epitope (HLA-DR) recognized by the antibody Bra38 is probably absent in cattle. The presence of HLA-DP analogue determined by the antibody BraFB6 has not been confirmed. The crossreactive MoAbs could be used for the detection of B lymphocytes and macrophages in veterinary immunology. 相似文献
2.
Regulation of Capacitation of Canine Spermatozoa during Co-culture with Heterologous Oviductal Epithelial Cells 总被引:2,自引:0,他引:2
AM Petrunkina K Simon A-R Günzel-Apel E Töpfer-Petersen 《Reproduction in domestic animals》2003,38(6):455-463
Progress of essential steps of the capacitation is coordinated in the oviductal isthmus, where sperm are stored in close contact with the epithelium. A crucial capacitational event is the phosphorylation of sperm membrane proteins. Regulation of the tyrosine phosphorylation by the oviduct has not been examined in dog sperm yet. The aim of this work was to study the effect of dog sperm binding to porcine oviductal epithelium on capacitation‐induced cellular and molecular changes. Epithelial cells were stripped from the oviducts of post‐puberal sows and cultured for 5–7 days at 39°C and 5% CO2 on Biomatrix‐covered Chamber slides. Sperm washed through Percoll was co‐incubated with the oviductal epithelium cell cultures in a bicarbonate Tyrode's medium. During co‐incubation, sperm membrane changes, the state of tyrosine phosphorylation and motility were determined after 3, 30, 90, 180, 240 and 360 min. Significant increases in the percentage of capacitated and dead cells were observed in unbound sperm, while bound sperm remained uncapacitated, live and motile. An increasing tyrosine phosphorylation of tail proteins in bound, unbound and control sperm suspensions and a subsequent phosphorylation of head proteins in unbound and control sperm suspensions were observed. A significant difference regarding head phosphorylation (p < 0.05) was found between sperm bound to oviductal epithelium and unbound sperm. Binding occurred mainly in sperm with non‐ phosphorylated heads, while higher proportions of phosphorylated cells were found in unbound populations. The head phosphorylation progressed significantly during incubation in unbound spermatozoa (p < 0.05); however, it was suppressed in population of sperm attached to oviductal epithelium. Significant correlations between motility parameters related to hyperactivation and tail phosphorylation were found in unbound sperm. These observations support the hypothesis that spermatozoa with non‐phosphorylated heads preferentially attach to epithelial cells. It can be concluded that tyrosine phosphorylation of head membrane proteins and capacitation are delayed in canine spermatozoa being in closed contact with oviductal epithelium. 相似文献
3.
J. Simon 《British poultry science》1980,21(4):309-313
1. A possible relationship between glucose tolerance and body‐fat content was examined in broilers selected at 2 and 4 weeks of age for fast or slow glucose disposal.
2. At 8 weeks of age, selected chickens were different in glucose tolerance but similar in body weight, food conversion efficiency, carcass composition and glucose‐induced insulin release.
3. Therefore, variations in glucose regulation and insulin sensitivity which are detectable at an early age, do not appear to be related to body composition in 8‐week‐old broilers. 相似文献
4.
Young pigs were exposed to an aerosol of a nonpathogenic strain of Escherichia coli and then were retained in air-pollutant exposure chambers for a 2-hour clearance period. In series 1 (n = 80 pigs), 40 exposed young pigs (principals; 15.5 days of age) were placed in an atmosphere of filtered room air + 50 ppm of atmospheric NH3 during the clearance period; control pigs were exposed to filtered room air without added NH3. In series 2 (n = 24 pigs), 12 exposed young pigs (principals; 6.2 days of age) were similarly maintained, but at a lower concentration of atmospheric NH3 (75 ppm). At the end of the clearance period pigs were killed and pulmonary bacterial clearance was determined. Pigs kept in the NH3-contaminated atmospheres (either concentration) harbored more bacteria, on the average, in their lungs than did the controls. If series 1 and 2 data were combined, pigs kept in the NH3-contaminated atmospheres had 51% more bacteria in their lungs than did the controls. Pulmonic weight and ratio of pulmonic weight to body weight of pigs kept in the NH3-contaminated atmosphere were greater than those of the controls in series 1, but not in series 2. Gross and histopathologic examinations of lung tissue generally revealed no differences between controls and principals in either series 1 or 2. 相似文献
5.
6.
Armitage SJ Jasim SA Marks AE Parker AG Usik VI Uerpmann HP 《Science (New York, N.Y.)》2011,331(6016):453-456
The timing of the dispersal of anatomically modern humans (AMH) out of Africa is a fundamental question in human evolutionary studies. Existing data suggest a rapid coastal exodus via the Indian Ocean rim around 60,000 years ago. We present evidence from Jebel Faya, United Arab Emirates, demonstrating human presence in eastern Arabia during the last interglacial. The tool kit found at Jebel Faya has affinities to the late Middle Stone Age in northeast Africa, indicating that technological innovation was not necessary to facilitate migration into Arabia. Instead, we propose that low eustatic sea level and increased rainfall during the transition between marine isotope stages 6 and 5 allowed humans to populate Arabia. This evidence implies that AMH may have been present in South Asia before the Toba eruption. 相似文献
7.
Case studies of apparel organisations, in two broadly distinguishable market groups in South Korea have been conducted for
this research. One of the case study organisations,company A, sells high fashion knit wear products manufactured by a foreign supplier and the other,company B, deals fashionable ladies wear supplied by 8 to 10 domestic apparel manufacturers. The study identifies common issues and
differences between these dissimilar apparel companies in their respective supply chain systems. The selected apparel systems
were analysed and categorised into four sectors, i.e.: production management, product distribution management, customer buying
behaviour analysis and the evaluation of business performance in terms of both quantity and quality. The analysis was conducted
as a pre-cursor to simulation studies to investigate the effects of apparel supply chain control parameters on the relevant
business performance. The predominant costs are the product cost and the outlet rent, both of which reflect the product volumes
ordered. The forecast errors are high for both apparel companies. Therefore, improving the forecasting techniques should significantly
reduce the costs and improve the profits. The data derived from the case studies can contribute new information on the globalised
supply chain study area, especially the approach to compare the international to domestic apparel entrepreneurs’ activities/finances
will be a useful guideline to compare relevant supply chain systems in other countries as well as in Korea. 相似文献
8.
9.
Toshiyuki Takai Patrick Lumanglas Daisuke Fujita Kazuhiro Sasaki Njato Michael Rakotoarisoa Yasuhiro Tsujimoto Nobuya Kobayashi Eliza Vie Simon 《Breeding Science》2021,71(5):615
The heading date is an important trait for determining regional and climatic adaptability in rice. To expand the adaptability of the indica rice cultivar ‘IR64’, we pyramided multiple early or late heading quantitative trait locus (QTLs) in the ‘IR64’ genetic background by crossing previously developed near-isogenic lines (NILs) with a single QTL for early or late heading. The effects of pyramiding QTLs were observed in three different climatic zones of the Philippines, Madagascar, and Japan. The early heading pyramiding lines (PYLs) headed 6.2 to 12.8 days earlier than ‘IR64’ while the late heading PYLs headed 18.8 to 27.1 days later than ‘IR64’. The PYLs tended to produce low grain yield compared to ‘IR64’. The low yield was not improved by combining SPIKE, which is a QTL that increases the number of spikelets per panicle. Conversely, ‘IR64-PYL(7+10)’ carrying Hd5 and Hd1 headed earlier, produced more tillers, and more panicles per m2 than ‘IR64’, and mitigated the yield decrease in early heading. These results suggest that the effects of pyramided QTLs on heading date were consistent across various environments and PYLs could be used to enhance the adaptation of ‘IR64’ in other rice growing environments. 相似文献
10.
There is an increasing trend to require more efficient use of water resources, both in urban and rural environments. A major mechanism that can be used to achieve greater efficiencies is the reuse of water that once would have been discarded into the environment after use. The reuse of water for agricultural irrigation is often viewed as a positive means of recycling water due to the potential large volumes of water that can be used. Recycled water can have the advantage of being a constant, reliable water source and reduces the amount of water extracted from the environment. In addition, in some cases treatment requirements may be need to be less than for water used in an urban environment due to less potential human contact. There are concerns and unknowns, however, about the impact of the quality of the recycled water, both on the crop itself and on the end users of the crops. Water quality issues that can create real or perceived problems in agriculture include nutrient and sodium concentrations, heavy metals, and the presence of contaminants such as human and animal pathogens, pharmaceuticals and endocrine disruptors. Social attitudes to the use of crops that have been irrigated with recycled waters and the resulting impact on market value of crops are also a major consideration. This paper will discuss the benefits from using different types of recycled water and outline the current knowledge and opinions relating to risks such as water quality issues. 相似文献