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81.
Automation of the measurement of the physiological and behavioural parameters of livestock has become an important goal for both scientists and farmers. Accurate data and knowledge about farmed animals, especially in cattle breeding, are needed. Proper early diagnosis of a cow's health status in real time allows for preventing the development of infection, oestrus detection and leads to reduced environmental stress. Thus, it contributes to more effective herd management. Among the physiological parameters, body temperature and its fluctuations are key indicators of health and well-being in animals. Currently, along with the development of technical solutions and their implementation, increasingly more attention is being paid to the continuously measurement of body core and peripheral temperature in animals. Recently there has been an increased number of publications devoted to this subject. However, there is a need to systematise this knowledge as these studies have had different purposes, have been performed in various environmental conditions, and the measurements were taken using different methods and equipment. As such, the results obtained by the different authors often may not be comparable. For this reason, this paper has two main purposes: to present the most widely used continuous methods of peripheral and body core temperature measurement, and to show its references values which characterise the individual locations of the cattle body in thermoneutral ambient. An analysis of the professional publications regarding measurements of peripheral and deep body temperature led to the conclusion that these methods have high research and diagnostic potential. However, it is necessary to standardised research to enable better and more comparable results, including among others; different cattle groups, animal age, health and environmental conditions. 相似文献
82.
83.
auf demKeller U Krampert M Kümin A Braun S Werner S 《European journal of cell biology》2004,83(11-12):607-612
Keratinocyte growth factor (KGF) is a potent and specific mitogen for different types of epithelial cells, and it can protect these cells from various insults. Due to these properties, it is of particular importance for the repair of injured epithelial tissues, and it is currently therapeutically explored for the treatment of radiation- and chemotherapy-induced mucosal epithelial damage in cancer patients. In this review we summarize the current knowledge on the role of KGF in tissue repair and cytoprotection, and we report on its mechanisms of action in keratinocytes. 相似文献
84.
Drapc1 expression during mouse embryonic development 总被引:2,自引:0,他引:2
We identified the mouse homolog of human DRAPC1 (APCDD1) gene, shown to be a target of Wnt/beta-catenin signaling pathway in cancer cell lines. Analysis of its spatiotemporal expression in mouse embryos from E7.5 to E14 showed that Drapc1 is expressed during development of the extraembryonic structures, nervous system, vascular system and inner ear. In addition, Drapc1 is expressed in the mesenchyme of several developing organs at sites of epithelio-mesenchymal interactions. Drapc1 expression was also found in the hair follicles of the adult mouse skin. Similarity of Drapc1 expression pattern to location of active beta-catenin in developing mouse embryo further suggests that mouse Drapc1 is a novel in vivo target gene of Wnt/beta-catenin signaling pathway. 相似文献
85.
Lu Y Bu L Zhou S Jin M Sundberg JP Jiang H Qian M Shi Y Zhao G Kong X Hu L 《Molecular genetics and genomics : MGG》2004,272(2):129-137
We describe here a spontaneous, autosomal recessive mutant mouse suffering from skin and hair defects, which arose in the outbred Kunming strain. By haplotype analysis and direct sequencing of PCR products, we show that this mutation is a new allele of the asebia locus with a naturally occurring mutation in the Scd1 gene (a CCC insertion at nucleotide position 835 in exon 5), which codes for stearoyl-CoA desaturase 1. This mutation introduces an extra proline residue at position 279 in the Scd1 protein. The mutant mice, originally designated km/km but now assigned the name Scd1 ab-Xyk (hereafter abbreviated as ab Xyk / ab Xyk ), have a similar gross and histological phenotype to that reported for previously characterized allelic asebia mutations ( Scd1 ab , Scd1 abJ , Scd1 ab2J , and Scd1 tm1Ntam ). Histological analysis showed they were also characterized by hypoplasic sebaceous glands and abnormal hair follicles. In a cross between Kunming- ab Xyk / ab Xyk and ABJ/Le- ab J / ab J mice, all the progeny showed the same phenotype, indicating that the two mutations were non-complementing and therefore allelic. Comparisons with the other four allelic mutants indicate that the Scd1 ab-Xyk mutation causes the mildest change in Scd1 function. This new mouse mutant is a good model not only for the study of scarring alopecias in humans, which are characterized by hypoplasic sebaceous glands, but also for studying the structure and function of the Scd1 protein.Communicated by G. ReuterThe first two authors contribute equally to this work 相似文献
86.
Rapid progress of in vitro techniques in the lastyears enabled the creation of organotypic skin cultures offering newpossibilities in wound treatment. Rebuilding of graft is one of the keyelementsof successful outcome of the procedure.In search for the best scaffold for organotypic skin culture, the novelcomposite xenogenic collagen based material with unique properties has beencreated and used to reconstitute full thickness human skin invitro. Based on our long established technology used for theproduction of collagen dressings for the treatment of burns, this novel,composite material offers excellent growth support of highly biodegradablespongy layer, combined with mechanical strength of collagen membrane. Themodulation of collagen properties was accomplished by consecutive treatmentwithhigh temperature and gamma irradiation. The use of the substrate enabled toobtain organotypic culture that resembles full thickness skin with fibroblastslayer and well-developed multilayer epithelium. Our new material offers easyhandling of obtained graft during surgery along with accelerated cell growth andcontrolled biodegradation of the culture support. 相似文献
87.
To investigate the origin and nature of the signals responsible for specification of the dermatomal lineage, excised axial organs in 2-day-old chick embryos were replaced by grafts of the dorsal neural tube, or the ventral neural tube plus the notochord, or aggregates of cells engineered to produce Sonic hedgehog (Shh), Noggin, BMP-2, Wnt-1, or Wnt-3a. By E10, grafts of the ventral neural tube plus notochord or of cells producing Shh led to differentiation of cartilage and muscles, and an impaired dermis derived from already segmented somites. In contrast, grafts of the dorsal neural tube, or of cells producing Wnt-1, triggered the formation of a feather-inducing dermis. These results show that the dermatome inducer is produced by the dorsal neural tube. The signal can be Wnt-1 itself, or can be mediated, or at least mimicked by Wnt-1. 相似文献
88.
Zhu Z Hotchkiss SA Boobis AR Edwards RJ 《Biochemical and biophysical research communications》2002,297(1):65-70
The complement and level of expression of P450 enzymes in male Fischer F344 rat whole skin and cultured keratinocytes were investigated using a panel of mono-specific antibodies. In whole skin microsomal fraction, immunoreactive bands corresponding to CYP2B12, CYP2C13, CYP2D1, CYP2D4, CYP2E1, CYP3A1, and CYP3A2 were detected whereas CYP1A1, CYP1A2, and CYP2C12 were absent. Skin levels were all between 0.1% and 4.7% of those found in liver, except for CYP2D4, which was not detected in liver. Keratinocytes were isolated from rat skin, cultured for up to 42 days, and changes in the levels of CYP3A1, CYP3A2, and CYP2E1 determined. Levels were low in isolated keratinocytes, but they increased markedly in culture, reaching a maximum at 10-14 days, where they were similar to those found in fresh skin. This suggests that primary keratinocytes grown in culture for 10-14 days may provide a useful experimental model to study P450-catalysed metabolism of xenobiotics in skin. 相似文献
89.
Suzuki Y Tasumi S Tsutsui S Okamoto M Suetake H 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2003,136(4):723-730
Among lectins in the skin mucus of fish, primary structures of four different types of lectin have been determined. Congerin from the conger eel Conger myriaster and AJL-1 from the Japanese eel Anguilla japonica were identified as galectin, characterized by its specific binding to β-galactoside. Eel has additionally a unique lectin, AJL-2, which has a highly conserved sequence of C-type lectins but displays Ca2+-independent activity. This is rational because the lectin exerts its function on the cutaneous surface, which is exposed to a Ca2+ scarce environment when the eel is in fresh water. The third type lectin is pufflectin, a mannose specific lectin in the skin mucus of pufferfish Takifugu rubripes. This lectin showed no sequence similarity with any known animal lectins but, surprisingly, shares sequence homology with mannose-binding lectins of monocotyledonous plants. The fourth lectin was found in the ponyfish Leiognathus nuchalis and exhibits homology with rhamnose-binding lectins known in eggs of some fish species. These lectins, except ponyfish lectin, showed agglutination of certain bacteria. In addition, pufflectin was found to bind to a parasitic trematode, Heterobothrium okamotoi. Taken together, these results demonstrate that skin mucus lectins in fish have wide molecular diversity. 相似文献
90.
Ben-Bassat H Chaouat M Zumai E Segal N Cinamon U Ron M Wexler MR Eldad A 《Cell and tissue banking》2000,1(4):303-312
The Israel National Skin Bank (INSB) was founded jointly by the Israel Defense Forces (IDF) Medical Corps and the Ministry of Health in 1986. The prime purpose of the Skin Bank is to treat burn victims incurred at war or during mass casualty incidences. The INSB Protocol is comprised of international skin bank protocols and our previous and present research results. They provide the framework for selecting optimal guidelines for procurement, processing, preservation, storage and evaluation of transplantation performance of viable skin grafts. For evaluation and direct comparison of graft performance of glycerolized or cryopreserved skin stored for long periods, we have applied a mouse recipient model developed by us. This model assesses graft performance before the rejection process takes place. The in vivo design has inherent clinical relevance, which is especially appealing. Cryopreserved skin performed better than glycerolized skin (p > 0.027), but fresh skin performed significantly better than cryopreserved skin (p > 0.003), as analyzed by the Mann–Whitney non-parametric test. Then graft performance of skin specimens were cryopreserved by programmed or stepwise freezing and stored at -80°C or in liquid nitrogen for 1 and 6–10 months was evaluated. The average score of skin preserved by programmed freezing and stored in liquid nitrogen is the highest for both storage periods. This method has a highly significant advantage (p < 0.007) over the others for 6–10 months storage, evaluated by graft adherence. Several interaction factors determine the quality of cryopreserved skin. Highly significant is the interaction factor/'combined effect' of sample variability with the method of cryopreservation or with the storage period. Finally, the results of paired comparison of selected histology criteria of cryopreserved to fresh skin indicated that storage of skin for up to 5 years did not impair significantly its performance compared to fresh skin, whereas, after six years of storage, there was a highly significant (p < 0.001) impairment in skin quality. We offer a simplified in vivo model and analysis for cryopreserved skin graft performance, suggesting that the evaluation procedures, which are issues of great interest in skin banking, may help future skin banks to make informed choices and decisions regarding quality issues. 相似文献