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81.
A new production method for figured fabric has been developed. The figured fabric generated in this study is a plain weave piled fabric and it shows the same figure on both sides unlike those fabrics woven on dobby or jacquard looms. It is woven by a specialty yarn called the chenille yarn which is obtained by separating each warp of a base fabric woven in leno structure. The base fabric is woven by inserting different colored weft each time in a certain sequence arranged according to the target figure image. A CAD software and a computerized controller have been developed to control all the motions of a conventional rapier loom and to handle the numerous weft insertion schedule efficiently.  相似文献   
82.
Trans epidermal water loss (TEWL), skin hydration status and pH were determined in 14 skin regions of five healthy male Beagle dogs (2–4 years) both before and after anaesthesia. Trans epidermal water loss was highest for the footpad and head and lowest for the inguinal region. Skin hydration status was higher in the ear but did not vary significantly in other regions. Skin pH was usually alkaline with the highest values on the lower back and tail. Following anaesthesia, TEWL and skin hydration were significantly lower on the head, upper back and footpad, and upper back and elbow respectively, while skin pH was unaffected by this procedure. While measurement of pH would seem to be valid anywhere on the body in anaesthetized dogs, regional factors should be considered when interpreting TEWL and skin hydration values and when treating regional skin diseases in veterinary practice.  相似文献   
83.
Chemical investigation of a marine-derived fungus, Penicillium steckii 108YD142, resulted in the discovery of a new tanzawaic acid derivative, tanzawaic acid Q (1), together with four known analogues, tanzawaic acids A (2), C (3), D (4), and K (5). The structures of tanzawaic acid derivatives 1–5 were determined by the detailed analysis of 1D, 2D NMR and LC-MS data, along with chemical methods and literature data analysis. These compounds significantly inhibited nitric oxide (NO) production and the new tanzawaic acid Q (1) inhibited the lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins and mRNA expressions in RAW 264.7 macrophages. Additionally, compound 1 reduced the mRNA levels of inflammatory cytokines. Taken together, the results of this study demonstrated that the new tanzawaic acid derivative inhibits LPS-induced inflammation. This is the first report on the anti-inflammatory activity of tanzawaic acid Q (1).  相似文献   
84.
The objective of this study was to investigate the common forms of reproductive disorders and trends of fertility in cattle and buffaloes in Middle Egypt, and investigate nutritional deficiencies or imbalances as a cause of infertility. During the period from 2003 to 2006 a total of 4276 animals (2755 cattle and 1521 buffaloes) were examined, during winter and summer at three districts of Middle Egypt. Based on the owner complains, animals were categorized as anestrum, repeat breeder and those for pregnancy diagnosis. Feedstuffs of these districts were assessed for nutrient and mineral contents. Animals were examined by rectal palpation and by transrectal ultrasonography. The results showed that, ovarian inactivity was the most common cause of anestrum, whereas endometritis was the main frequent finding of repeat breeding. District, season and year affected the incidences of infertility. The pregnancy rate remained constant (cattle) or increased (buffaloes) from 2003 to 2006. The incidence of ovarian inactivity in both species decreased over the same period. In winter, the commonly used feedstuffs would be adequate to supply the animals with needs, but in summer, rations seem to be deficient in many essential nutrients. In conclusion, ovarian inactivity is the main cause of infertility in cattle and buffaloes in Middle Egypt. There is a link between poor nutrition in summer and the high incidence of ovarian inactivity. Fertility trends during the past few years are encouraging.  相似文献   
85.
Potential estrogenic and antiandrogenic effects of permethrin in rats   总被引:4,自引:0,他引:4  
Many environmental chemicals including pesticides have been reported to possess hormonal activities, and thus are classified as endocrine disruptors. Permethrin, a synthetic pyrethroid insecticide, is used worldwide, which provides potential environmental exposure. However, relatively few studies have reported on hormonal activities, particularly estrogenic and androgenic activities of permethrin, and the results of these studies are in some respects contradictory. Therefore, this study investigated the potential estrogenic and androgenic activities of permethrin in vitro and in vivo. We conducted an uterine Calbindin-D9k (CaBP-9k) gene expression assay and an uterotrophic assay for estrogenic activity, and a Hershberger assay for androgenic activity. The CaBP-9k gene, one of the intracellular calcium binding proteins, is estrogen-responsive in the uterus. The rat uterotrophic and Hershberger assays are generally used as in vivo short-term screening assays for detecting the estrogenic and androgenic activities of chemicals, although these assays are still being validated by the Organization for Economic Cooperation and Development (OECD). Northern blot analysis showed the induction of uterine CaBP-9k mRNA level in response to permethrin as well as co-administration of permethrin with E2. In the uterotrophic assay using 18-day-old female rats, subcutaneous treatments with permethrin (10 to 800 mg/kg) for three days increased relative uterine wet weights, and E2-induced uterine weights. These effects were statistically significant at 800 and 200 mg/kg, respectively. Moreover, permethrin-induced uterine weights were inhibited by the co-administration of ICI 182,780, an antiestrogen. In the Hershberger assay, the administration of permethrin orally to testosterone propionate-treated castrated male rats led to statistically significant reductions in androgen-dependent sex accessory tissue (ventral prostate, seminal vesicles, levator ani and bulbocavernosus muscles, Cowper's gland and glans penis) weights at all doses tested (10, 50 and 100 mg/kg). These results suggest that permethrin might have estrogen-like effects on female rats, but antiandrogen-like effects on males.  相似文献   
86.
Although rodents have previously been used in ecotoxicological studies, they are expensive, time-consuming, and are limited by strict legal restrictions. The present study used a zebrafish (Danio rerio) model and generated data that was useful for extrapolating toxicant effects in this system to that of humans. Here we treated embryos of the naive-type as well as a transiently transfected zebrafish liver cell line carrying a plasmid (phAhRE-EGFP), for comparing toxicity levels with the well-known aryl hydrocarbon receptor (AhR)-binding toxicants: 3,3'',4,4'',5-pentachlorobiphenyl (PCB126), 2,3,7,8-tetrachlorodibenzo-p-dioxin, and 3-methylcholanthrene. These toxicants induced a concentration-dependent increase in morphological disruption, indicating toxicity at early life-stages. The transient transgenic zebrafish liver cell line was sensitive enough to these toxicants to express the CYP1A1 regulated enhanced green fluorescent protein. The findings of this study demonstrated that the zebrafish in vivo model might allow for extremely rapid and reproducible toxicological profiling of early life-stage embryo development. We have also shown that the transient transgenic zebrafish liver cell line can be used for research on AhR mechanism studies.  相似文献   
87.
We identified a potential molecular marker associated with meat quality traits in the myosin heavy chain 4, MYH4 gene of Landrace pigs. Sequencing revealed a single nucleotide polymorphism (SNP; g.‐1398G>T) in the 5' upstream region of MYH4. It was significantly associated with the number of type IIa muscle fibers and water‐holding capacity based on filter‐paper fluid uptake. The GG genotype groups had a greater number of type IIa fibers and a larger area composed of type IIa fibers than the other genotype group (P = 0.004 and P = 0.061, respectively). Expression level of MYH4 gene in the genotype TT or GT was higher than in genotype of GG (P < 0.0001). The T allele may enhance expression level of MYH4 gene and then the portion of IIb type fiber in the muscle be increased by the T allelle. Therefore, we suggest that the g.‐1398G>T in the 5' upstream region of the porcine MYH4 may be used as a molecular marker for meat quality traits, although its functional effect is not defined yet.  相似文献   
88.
The current study investigated the possibility of using the AMH concentration as a predictor of the ability of Korean Hanwoo cows to produce cumulus‐oocyte complexes, embryos that survive after transfer as well as the pregnancy outcome of surrogates. Eight sessions of ovum pick‐up (OPU) were performed with 19 donor cows at an interval of 3–4 days. Antral follicle count (AFC), oocyte quality and in vitro embryo development were recorded for each cow. Embryos produced from cows with different AMH profiles were transferred into recipients (n = 96). Cows in the high (≥0.25 ng/ml) and intermediate (0.1≥ to <0.25 ng/ml) AMH groups had a significantly higher AFC per OPU session (20.40 ± 1.36 and 16.91 ± 1.52, respectively; mean ± standard deviation) than cows in the low AMH group (<0.1 ng/ml; 12.19 ± 2.14). In addition, more cumulus‐oocyte complexes per donor were recovered in the high (11.46 ± 1.22) and intermediate (7.38 ± 0.83) AMH groups than in the low AMH group (4.77 ± 0.44). The percentage of oocytes reached blastocyst stage was significantly higher in the intermediate (47.0%) and high (38.5%) AMH groups than in the low AMH group (32.3%). The number of embryos produced per cow was higher in the high (3.9 ± 0.2) and intermediate (6.9 ± 0.6) AMH groups than in the low AMH group (2.2 ± 0.3). The percentage of embryos that gave birth to viable calves when transferred into recipients was higher for those derived from cows in the intermediate AMH group (50.7%) than for those derived from cows in the low (35.7%) and high (36.4%) AMH groups. In conclusion, a single measurement of AMH concentration predicted the in vitro embryo production potential of donor Korean native cows before OPU and is linked with embryo viability after transfer into recipients.  相似文献   
89.
为了制备甲基营养型芽孢杆菌NKG-1可湿性粉剂,评价其防病促生效果。试验以NKG-1为试材,通过筛选载体和助剂,利用混料设计确定可湿性粉剂的最优配方,并进行药效测定。结果表明:NKG-1可湿性粉剂的最佳载体为白炭黑,最佳助剂为烷基萘磺酸盐甲醛缩聚物和嵌段共聚物混合物(Morwet D-500)及烷基萘磺酸盐(Petro AA)。混料设计确定了最优质量配比为:白炭黑:Morwet D-500:Petro AA=72:16:12。药效试验结果表明:NKG-1可湿性粉剂100倍液处理番茄植株后,其鲜重、干重、株高以及根长分别较对照增加了53.34%、61.01%、88.02%、78.53%,对番茄灰霉病的平均防治效果高达82.02%。本研究确定了甲基营养型芽孢杆菌NKG-1可湿性粉剂的最优配比,评测了制剂的药效,为NKG-1的生产应用奠定了试验基础。  相似文献   
90.
In this study, a structured survey questionnaire was used to determine consumers' preferences and behavior with regard to horse meat at a horse meat restaurant located in Jeju, Korea, from October 1 to December 24, 2005. The questionnaire employed in this study consisted of 20 questions designed to characterize six general attributes: horse meat sensory property, physical appearance, health condition, origin, price, and other attributes. Of the 1370 questionnaires distributed, 1126 completed questionnaires were retained based on the completeness of the answers, representing an 82.2% response rate. Two issues were investigated that might facilitate the search for ways to improve horse meat production and marketing programs in Korea. The first step was to determine certain important factors, called principal components, which enabled the researchers to understand the needs of horse meat consumers via principal component analysis. The second step was to define consumer segments with regard to their preferences for horse meat, which was accomplished via cluster analysis. The results of the current study showed that health condition, price, origin, and leanness were the most critical physical attributes affecting the preferences of horse meat consumers. Four segments of consumers, with different demands for horse meat attributes, were identified: origin‐sensitive consumers, price‐sensitive consumers, quality and safety‐sensitive consumers, and non‐specific consumers. Significant differences existed among segments of consumers in terms of age, nature of work, frequency of consumption, and general level of acceptability of horse meat.  相似文献   
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