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101.
The life-history of Euclinostomum heterostomum (Rudolphi, 1809), a clinostomid trematode occurring in the oesophagus and buccal cavity of pond heron Ardeola grayii and cattle egret Bubulcus ibis at Visakhapatnam, India, has been traced from egg to adult stage, based on field and laboratory studies. Eggs released by gravid flukes hatched into miracidia in 10 days. The snail Indoplanorbis exustus served as the first intermediate host and the intramolluscan phase, involving the development of two redial generations and cercariae, took two months. Natural infections with the metacercaria were found in the kidneys and liver of the fish Channa punctatus and muscles of C. orientalis. Laboratory experiments demonstrated that more than 2 months are required for the development of the cercaria into the infective metacercarial stage. The morphology of all of the stages in the life-cycle has been studied in detail, as well as the growth characteristics of the metacercaria within the fish host. Two phases in the metacercarial growth were noted, a lag phase followed by an exponential phase. Allometric growth parameters of body proportions and organs of the metacercaria and the adult are compared. The validity of various species included in the genus Euclinostomum is discussed. 相似文献
102.
R. Madhavi 《Biotechnic & histochemistry》1971,46(3):105-109
Various combinations of the oxidation method for demonstrating keratin in shell material of amphistomes were tried. Acidified permanganate worked more efficiently than performic and peracetic acids, and Alcian blue and aldehyde fuchsin excelled other basic dyes for subsequent staining. For the permanganate-Alcian blue reaction, sections of material fixed in Susa or Bouin were oxidized in 0.3% permanganate in 0.3% H2SO4 for 5 min., decolourized in 1% oxalic acid, stained in 3% Alcian blue in 2 N H2SO4 and counterstained with eosin. The shell globules stained a deep blue. For permanganate aldehyde fuchsin staining, the sections were stained in aldehyde fuchsin for 1 hr, after oxidation with permanganate. The shell globules then stained a deep magenta. The catechol and fast red reactions were negative in amphistomes and the specimens lack the characteristic amber colour due to quinone tanning. 相似文献
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Present study was undertaken to determine if an interaction exists during co-administration of ciprofloxacin with phenytoin. Eight healthy male rabbits received oral phenytoin, 40 mg/kg, od, for 7 days. On day 7, phenytoin blood sampling was done at times 0, 0.1, 1, 2, 3, 4, 5, 6, 8 and 24 hr. From day 8 to 14, phenytoin was co-administered with oral ciprofloxacin, 70 mg/kg, od. On day 14, blood samples were collected as previously described. Pharmacokinetic analysis revealed significant decrease in steady state maximum concentration (Cmax), through concentration (Cmin), elimination half life (t 1/2 e) and the area under plasma time concentration curve (AUC0-24) of phenytoin when co-administered with ciprofloxacin. It warrants close monitoring of levels when these two agents are given simultaneously. 相似文献
106.
Requirement for Ras/Rac1-mediated p38 and c-Jun N-terminal kinase signaling in Stat3 transcriptional activity induced by the Src oncoprotein. 总被引:9,自引:0,他引:9 下载免费PDF全文
107.
Y. Bhargav Kumar Nandan Kumar Lijo John Hridoy Jyoti Mahanta S. Vaikundamani Selvaraman Nagamani G. Madhavi Sastry G. Narahari Sastry 《Proteins》2024,92(2):179-191
The cation-aromatic database (CAD) is a comprehensive repository of cation-aromatic motifs found in experimentally determined protein structures, first reported in 2007 [Proteins, 2007, 67, 1179]. The present article is an update of CAD that contains information of approximately 27.26 million cation-aromatic motifs. CAD uses three distance parameters (r, d1, and d2) to determine the position of the cation relative to the centroid of the aromatic residue and classifies the motifs as cation-π or cation-σ interactions. As of June 2023, about 193 936 protein structures were retrieved from Protein Data Bank, and this resulted in the identification of an impressive number of 27 255 817 cation-aromatic motifs. Among these motifs, spherical motifs constituted 94.09%, while cylindrical motifs made up the remaining 5.91%. When considering the interaction of metal ions with aromatic residues, 965 564 motifs are identified. Remarkably, 82.08% of these motifs involved the binding of metal ions to the amino acid HIS. Moreover, the analysis of binding preferences between cations and aromatic residues revealed that the HIS-HIS, PHE-ARG, and TRP-ARG pairs exhibited a preferential geometry. The motif pair HIS-HIS was the most prevalent, accounting for 19.87% of the total, closely followed by TYR-LYS at 10.17%. Conversely, the motif pair TRP-HIS had the lowest occurrence, representing only 4.20% of the total. The data generated help in revealing the characteristics and biological functions of cation-aromatic interactions in biological molecules. The updated version of CAD (Cation-Aromatic Database V2.0) can be accessed at https://acds.neist.res.in/cadv2 . 相似文献
108.
109.
A Review on Design Strategies for Carbon Based Metal Oxides and Sulfides Nanocomposites for High Performance Li and Na Ion Battery Anodes 下载免费PDF全文
Yi Zhao Luyuan Paul Wang Moulay Tahar Sougrati Zhenxing Feng Yann Leconte Adrian Fisher Madhavi Srinivasan Zhichuan Xu 《Liver Transplantation》2017,7(9)
Carbon‐oxide and carbon‐sulfide nanocomposites have attracted tremendous interest as the anode materials for Li and Na ion batteries. Such composites are fascinating as they often show synergistic effect compared to their singular components. Carbon nanomaterials are often used as the matrix due to their high conductivity, tensile strength, and chemical stability under the battery condition. Metal oxides and sulfides are often used as active material fillers because of their large capacity. Numerous works have shown that by taking one step further into fabricating nanocomposites with rational structure design, much better performance can be achieved. The present review aims to present and discuss the development of carbon‐based nanocomposite anodes in both Li ion batteries and Na ion batteries. The authors introduce the individual components in the composites, i.e., carbon matrices (e.g., carbon nanotube, graphene) and metal oxides/sulfides; followed by evaluating how advanced nanostructures benefit from the synergistic effect when put together. Particular attention is placed on strategies employed in fabricating such composites, with examples such as yolk–shell structure, layered‐by‐layered structure, and composite comprising one or more carbon matrices. Lastly, the authors conclude by highlighting challenges that still persist and their perspective on how to further develop the technologies. 相似文献
110.