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41.
Summary The author reports on the clinical and mycological studies of a case of black-grain maduromycosis in a woman from Santa Maria (Province of Catamarca, Argentine).Cultures of black grains in Sabouraud medium have developed colonies ofMadurella mycetomi and also ofMadurella grisea Mackinnon, Ferrada &Montemayor, 1949.The author questioned, which of the two species is the etiological agent in the present case and he concluded that the microscopic aspect of the black grain permits to suppose thatMadurella mycetomi is the agent in this case.

En homenaje al Prof. Tibor Benedek.  相似文献   
42.
Summary The author make a clinical and parasitological study of one new observation of histoplasmosis, parasitical rethiculo-histiocitosis or Darling's disease byHistoplasma capsulatum Darling, 1906 in a man 59 year old with pulmonary tuberculouse.His lesions in the mucouse of the mouth and in the lymph-nodes would healed with sulphadiacine treatment.It is the 7th. observation in Argentina.  相似文献   
43.
H. Bai  Y. Sun  N. Liu  Y. Liu  F. Xue  Y. Li  S. Xu  A. Ni  J. Ye  Y. Chen  J. Chen 《Animal genetics》2018,49(3):226-236
Beak deformity (crossed beaks) is found in several indigenous chicken breeds including Beijing‐You studied here. Birds with deformed beaks have reduced feed intake and poor production performance. Recently, copy number variation (CNV) has been examined in many species and is recognized as a source of genetic variation, especially for disease phenotypes. In this study, to unravel the genetic mechanisms underlying beak deformity, we performed genome‐wide CNV detection using Affymetrix chicken high‐density 600K data on 48 deformed‐beak and 48 normal birds using penncnv . As a result, two and eight CNV regions (CNVRs) covering 0.32 and 2.45 Mb respectively on autosomes were identified in deformed‐beak and normal birds respectively. Further RT‐qPCR studies validated nine of the 10 CNVRs. The ratios of six CNVRs were significantly different between deformed‐beak and normal birds (< 0.01). Within these six regions, three and 21 known genes were identified in deformed‐beak and normal birds respectively. Bioinformatics analysis showed that these genes were enriched in six GO terms and one KEGG pathway. Five candidate genes in the CNVRs were further validated using RT‐qPCR. The expression of LRIG2 (leucine rich repeats and immunoglobulin like domains 2) was lower in birds with deformed beaks (< 0.01). Therefore, the LRIG2 gene could be considered a key factor in view of its known functions and its potential roles in beak deformity. Overall, our results will be helpful for future investigations of the genomic structural variations underlying beak deformity in chickens.  相似文献   
44.
鼻咽癌对我国南部居民的健康造成严重的威胁.为了研究鼻咽癌的发病机理,本研究采用了蛋白质组学技术分析和比较了鼻咽癌细胞系(HNE1和CNE1)与永生化的鼻咽上皮细胞系的蛋白质表达谱.采用双向凝胶电泳分离提取的全细胞蛋白质,通过PDQuest软件分析找出在肿瘤中表达变化的蛋白质点,用基质辅助激光解析电离飞行时间串联质谱(MALDI- TOF/TOF-MS)进行鉴定.共得到了15个在肿瘤细胞系中表达上调和18个在肿瘤细胞系中表达下调的蛋白质,并对其中一些蛋白质的表达进行免疫印迹的验证.这些表达差异的蛋白质与细胞的增殖和调亡、癌症的转移,细胞骨架,信号传导等有关.本研究鉴定了一批可能作为鼻咽癌治疗的药物靶标的蛋白质,并对研究鼻咽癌发病机理提供了相关的线索.  相似文献   
45.
46.
Submerged cultures of Ganoderma lucidum are used to produce fungal mycelium, which is used as a functional food and in the production of various triterpenoids, including ganoderic acids (GAs). Specific culture approaches that produce fungal mycelium with high levels of GAs and good biological activity are critical in the functional food industry. In this study, a solid-medium culture approach to producing mycelium was compared to the submerged culture system. Production of GAs, biomass, intracellular polysaccharides, and cytotoxicity of the cultured mycelium were compared as between solid and submerged culture. Growing G. lucidum strains on solid potato dextrose agar medium increased biomass, the production of ganoderic acid 24 (lanosta-7,9(11), 24-trien-3α-o1-26-oic acid), GAs, and total intracellular polysaccharides as compared to fungi grown in submerged culture. Triterpenoid-enriched methanol extracts of mycelium from solid-medium culture showed higher cytotoxicity than those from submerged culture. The IC(50) values of methanol extracts from solid-medium culture were 11.5, 8.6, and 9.9 times less than submerged culture on human lung cancer cells CH27, melanoma cells M21, and oral cancer cells HSC-3 respectively. The squalene synthase and lanosterol synthase coding genes had higher expression on the culture of solid potato dextrose medium. This is the first report that solid-medium culture is able to increase GA production significantly as compared to submerged culture and, in the process, produces much higher biological activity. This indicates that it may be possible to enhance the production of GAs by implementing mycelium culture on solid medium.  相似文献   
47.
Xie M  Liu XS  Xu YJ  Zhang ZX  Bai J  Ni W  Chen SX 《生理学报》2007,59(1):94-102
本研究旨在探讨细胞外信号调节激酶1/2(extracellular signal-regulated kinase,ERK1/2)信号通路在慢性哮喘模型大鼠支气管平滑肌细胞(bronchial smooth muscle cells,BSMCs)迁移能力改变中的调控作用。应用卵清蛋白致敏和雾化方法制备大鼠慢性哮喘模型,体外培养大鼠BSMCs,采用免疫荧光细胞化学、Western blot和RT-PCR方法检测ERK1/2信号通路的表达,分别用平面迁移实验和跨膜迁移实验来评价BSMCs的活动和趋向迁移能力,并比较用和不用ERK1/2信号通路干预剂的差异。Western blot结果显示慢性哮喘模型大鼠BSMCs中总ERK1/2(9.13±0.87)较对照组(4.68±0.59)明显增加,磷酸化ERK1/2(p-ERK1/2)占总ERK1/2的比值(0.55±0.05)较对照组(0.48±0.04)显著提高(n=10,P<0.01)。慢性哮喘组ERK1和ERK2 mRNA的表达(1.83±0.24和1.07±0.11)较对照组(0.58±0.14和0.51±0.12)明显增高(n=10,P<0.01)。在平面迁移实验中,慢性哮喘大鼠BSMCs的迁移最远距离是对照组的(2.9±0.1)倍,在ERK1/2激动剂表皮生长因子(epidermal growth factor, EGF)刺激下增加到(5.0±0.2)倍,而在30μmol/L PD98059的作用后下降到(1.7±0.2)倍。正常对照大鼠BSMCs平面迁移能力对PD98059的反应较慢性哮喘组弱,仅在100μmol/L PD98059的作用下下降到(0.8±0.1)倍。跨膜迁移实验中,慢性哮喘大鼠BSMCs的跨膜迁移细胞是对照组的(1.9±0.1)倍,在EGF刺激下增加到(3.1±0.2)倍,而在30μmol/L PD98059作用后下降到(1.45±0.2)倍。这些结果表明慢性哮喘模型大鼠BSMCs的迁移能力明显增强,ERK1/2信号通路在该功能变化的调控中可能发挥了重要作用。  相似文献   
48.
The central cell characterizes the angiosperm female gametophyte (embryo sac or megagametophyte) in that it directly participates in “double fertilization” to initiate endosperm development, a feature distinguishing angiosperm from all other plant taxa. Polygonum‐type central cell is a binucleate cell that, upon fertilization with one of the two sperm cells, forms triploid endosperm to nourish embryo development. Although the formation and the structure of central cell have well been elucidated, the molecular mechanisms for its specification and development remain largely unknown. The central cell plays a critical role in pollen tube guidance during pollination and in endosperm initiation after fertilization. Recently, a group of mutants affecting specific steps of central cell development and function have been identified, providing some clues in understanding these questions. This review summarizes our current knowledge about central cell development and function, and presents overview about hypotheses for its evolution. genesis 48:466–478, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
49.
目的:观察奥扎格雷钠联合依达拉奉治疗急性脑梗死的临床疗效。方法:将160例急性脑梗死患者随机分为治疗组和对照组,每组各80例,治疗组采用注射用奥扎格雷钠联合依达拉奉治疗,对照组仅采用注射用奥扎格雷钠治疗,观察两组患者入院及治疗14d后临床疗效,神经功能缺损评分变化并进行对比分析。结果:治疗组的显效率为85.9%(67/78),对照组显效率为70.9%(56/79),两组显效率有显著性差异(x2=5.12,P=0.022),两组患者治疗14d后,神经功能的恢复情况与治疗前相比均有显著性差异(P<0.05),且治疗组与对照组治疗后比较有显著性差异,具有统计学意义(P<0.05)。结论:奥扎格雷钠联合依达拉奉治疗急性脑梗死较单独使用奥扎格雷钠疗效显著,是治疗急性脑梗死的有效方法。  相似文献   
50.
Aims Exotic fast-growing tree species have been commonly planted as pioneer species to facilitate ecological restoration in South China. Their growth and resource utilization behavior related to intrinsic physiology and structural properties have profound influences on forest ecosystem. However, the contrastive research focusing on water utilization features along with xylem anatomical properties between native and exotic species is scarce in South China. The objective of this study is to investigate the sapwood anatomical characteristics and water utilization conditions of native and exotic fast-growing species, and to elucidate the relationship between sap-flux density and conduit features.Methods We measured sap-flux density, conduit length, diameter and density of four native species (Schima superba, Michelia macclurei, Castanopsis hystrix and Castanopsis fissa) and four exotic species (Eucalyptus citriodora, Eucalyptus urophylla × grandis, Acacia auriculaeformis and Acacia mangium). Sap flux density was measured based on the Granier's thermal dissipation probe method. The whole-tree water transport was quantified by multiplying sap-flux density by sapwood area. The measurements of conduit characteristics were conducted by using segregation and slice method.Important findings Sapwood area increased with the growing diameter at breast height (DBH) as a power function. Native species had a larger water-conducting tissue area than exotic species at the same DBH value when trees grew to a size with a certain value of DBH. The conduit diameter of exotic species was significantly larger than that of native species. Conversely, native species, such as S. superba and M. macclurei, had longer conduit length and higher conduit density than other tree species. Based on a physiological interpretation of the measured conduit characteristics, native tree species developed a safe water transport system while exotic fast-growing tree species come into being an efficient system instead. Water transport increased with the growing DBH as a power function, and the exponent for native species (1.60) was higher than that for exotic species (1.22). Under the combined impact of sap-flux density and sapwood area, native species presented a larger water transport at a larger DBH value, indicating that growth advantage of exotic fast-growing species might weaken as DBH increased.  相似文献   
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