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排序方式: 共有2191条查询结果,搜索用时 15 毫秒
61.
Yuyu Wang Shiliang Yu Guojun Ma Songbo Chen Ye Shi Yuhong Yang 《International Journal of Food Science & Technology》2014,49(4):983-989
The proximate composition and amino acid compositions of the muscle of wild and farmed Pseudobagrus ussuriensis were compared. The lipid content of the farmed fish was significantly higher, while moisture content was significantly lower, than those of the wild fish. Pseudobagrus ussuriensis protein has a well‐balanced amino acid composition. The percentages of total amino acids, essential amino acids, nonessential amino acids and delicious amino acids were significantly higher in the wild than those in farmed fish. The ratios of WEAA to WTAA (42.78%–43.02%) and WEAA to WNEAA (85.52%–87.74%) were comparable to the reference values of 40% and above 60% recommended by FAO/WHO. According to the amino acid scores, methionine would have been described as the first limiting amino acid, and Lys had the highest score for the protein in both wild and farmed Pseudobagrus ussuriensis. This study shows that Pseudobagrus ussuriensis under investigation have high nutritional qualities and are good protein resources. 相似文献
62.
63.
Mass detection is a very important process for breast cancer diagnosis and computer aided systems. It can be very complex when the mass is small or invisible because of dense breast tissue. Therefore, the extraction of suspicious mass region can be very challenging. This paper proposes a novel segmentation algorithm to identify mass candidate regions in mammograms. The proposed system includes three parts: breast region and pectoral muscle segmentation, image enhancement and suspicious mass regions identification. The first two parts have been examined in previous studies. In this study, we focused on suspicious mass regions identification using a combination of Havrda & Charvat entropy method and Otsu's N thresholding method. An open access Mammographic Image Analysis Society (MIAS) database, which contains 59 masses, was used for the study. The proposed system obtained a 93% sensitivity rate for suspicious mass regions identification in 56 abnormal and 40 normal images. 相似文献
64.
目的:观察急性等容血液稀释(ANH)自体血回输对老年骨科手术患者脑电双谱指数与肌松效应的影响,探究含有麻醉药成分的自体血回输对术后麻醉苏醒质量及安全性的影响。方法:择期骨科手术患者40例,年龄65~75岁,体质量55~80 kg,ASA Ⅰ~Ⅱ级,预计术中出血量≥600 mL。患者随机分为2组(n=20):A组为进行ANH组,在麻醉诱导平稳后实施ANH,血细胞比容(Hct)目标值28%~30%;B组为对照组,即术中常规补液,不进行ANH。于术毕回输自体血时(T1)、回输10 min(T2)、20 min(T3)、30 min(T4)、40 min(T5)、50 min(T6)、60 min(T7)各时点观测两组患者脑电双频指数(BIS)、四个成串刺激(TOF值)及丙泊酚、顺式阿曲库铵的血浆药物浓度变化;观察并记录术前(T0)及T7时点血气变化,观察患者拔除气管导管的时间以及苏醒质量。结果:A组BIS值在术后T6、T7时点明显低于B组(P<0.05),A组TOF值在T5、T6、T7时点明显低于B组(P<0.05);A组与B组术后丙泊酚、顺式阿曲库铵的血药浓度组间比较差异无显著性(P>0.05);A组在术后T7时点乳酸(Lac)值明显高于B组(P<0.05);A组拔除气管导管的时间明显长于B组(P<0.05);A组Aldrete评分明显低于B组(P<0.05)。结论:ANH后术毕自体血回输可增加血浆中麻醉药物浓度,加深患者的麻醉深度,增强肌松效应,使老年患者呼吸功能恢复和拔管时间延迟。 相似文献
65.
《Food Control》2015
Chinese red pepper (Zanthoxylum bungeanum Maxim.) leaf (ZML) extract contains high amounts of phenolic compounds possessing high total antioxidant capacity and hydroxyl, 1, 1-dipheny-2-picrylhydrazyl (DPPH) free radical scavenging activity. ZML extract was investigated as a natural antioxidant for the lipid stability of salted silver carp (Hypophthalmichthys molitrix) throughout salting and drying. Both dorsal and ventral muscles were examined for differences in moisture content, salt content, total lipid content, and degree of lipid oxidation. The hexanal content, Thiobarbituric acid reactive substances (TBARS) value, and lipoxygenase (LOX) activity in the ventral muscle were significantly higher than those of the dorsal muscle (p < 0.05). In the treatments with ZML extract, the hexanal content, the TBARS value, and the LOX activity were significantly lower (p < 0.05) during processing both in the dorsal and ventral muscles. The sensory qualities of processed salted fish could be improved with the amount of 0.030% extract in the dorsal muscle and 0.045% extract in the ventral muscle. These results showed that ZML extract can be a source of natural antioxidants and used as a food additive. 相似文献
66.
67.
Ok-Kyung Hwang Jin-Kyu Park Eun-Joo Lee Eun-Mi Lee Ah-Young Kim Kyu-Shik Jeong 《International journal of molecular sciences》2016,17(2)
TGF-β1 is known to inhibit muscle regeneration after muscle injury. However, it is unknown if high systemic levels of TGF-β can affect the muscle regeneration process. In the present study, we demonstrated the effect of a CCl4 intra-peritoneal injection and losartan (an angiotensin II type 1 receptor antagonist) on skeletal muscle (gastrocnemius muscle) injury and regeneration. Male C57BL/6 mice were grouped randomly as follows: control (n = 7), CCl4-treatment group (n = 7), and CCl4 + losartan treatment group (n = 7). After CCl4 treatment for a 16-week period, the animals were sacrificed and analyzed. The expression of dystrophin significantly decreased in the muscle tissues of the control group, as compared with that of the CCl4 + losartan group (p < 0.01). p(phospho)-Smad2/3 expression significantly increased in the muscles of the control group compared to that in the CCl4 + losartan group (p < 0.01). The expressions of Pax7, MyoD, and myogenin increased in skeletal muscles of the CCl4 + losartan group compared to the corresponding levels in the control group (p < 0.01). We hypothesize that systemically elevated TGF-β1 as a result of CCl4-induced liver injury causes skeletal muscle injury, while losartan promotes muscle repair from injury via blockade of TGF-β1 signaling. 相似文献
68.
69.
A guide to analysis and reconstruction of serial block face scanning electron microscopy data 下载免费PDF全文
Serial block face scanning electron microscopy (SBF‐SEM) is a relatively new technique that allows the acquisition of serially sectioned, imaged and digitally aligned ultrastructural data. There is a wealth of information that can be obtained from the resulting image stacks but this presents a new challenge for researchers – how to computationally analyse and make best use of the large datasets produced. One approach is to reconstruct structures and features of interest in 3D. However, the software programmes can appear overwhelming, time‐consuming and not intuitive for those new to image analysis. There are a limited number of published articles that provide sufficient detail on how to do this type of reconstruction. Therefore, the aim of this paper is to provide a detailed step‐by‐step protocol, accompanied by tutorial videos, for several types of analysis programmes that can be used on raw SBF‐SEM data, although there are more options available than can be covered here. To showcase the programmes, datasets of skeletal muscle from foetal and adult guinea pigs are initially used with procedures subsequently applied to guinea pig cardiac tissue and locust brain. The tissue is processed using the heavy metal protocol developed specifically for SBF‐SEM. Trimmed resin blocks are placed into a Zeiss Sigma SEM incorporating the Gatan 3View and the resulting image stacks are analysed in three different programmes, Fiji, Amira and MIB, using a range of tools available for segmentation. The results from the image analysis comparison show that the analysis tools are often more suited to a particular type of structure. For example, larger structures, such as nuclei and cells, can be segmented using interpolation, which speeds up analysis; single contrast structures, such as the nucleolus, can be segmented using the contrast‐based thresholding tools. Knowing the nature of the tissue and its specific structures (complexity, contrast, if there are distinct membranes, size) will help to determine the best method for reconstruction and thus maximize informative output from valuable tissue. 相似文献
70.
Giuseppe Donato Mangano Malak Fouani Daniela DAmico Valentina Di Felice Rosario Barone 《International journal of molecular sciences》2022,23(6)
Cachexia is a multifactorial and multi-organ syndrome that is a major cause of morbidity and mortality in late-stage chronic diseases. The main clinical features of cancer-related cachexia are chronic inflammation, wasting of skeletal muscle and adipose tissue, insulin resistance, anorexia, and impaired myogenesis. A multimodal treatment has been suggested to approach the multifactorial genesis of cachexia. In this context, physical exercise has been found to have a general effect on maintaining homeostasis in a healthy life, involving multiple organs and their metabolism. The purpose of this review is to present the evidence for the relationship between inflammatory cytokines, skeletal muscle, and fat metabolism and the potential role of exercise training in breaking the vicious circle of this impaired tissue cross-talk. Due to the wide-ranging effects of exercise training, from the body to the behavior and cognition of the individual, it seems to be able to improve the quality of life in this syndrome. Therefore, studying the molecular effects of physical exercise could provide important information about the interactions between organs and the systemic mediators involved in the overall homeostasis of the body. 相似文献