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61.
Szenthe B Frost C Szilágyi L Patthy A Naudé R Gráf L 《Biochimica et biophysica acta》2005,1748(1):35-42
One of ostrich (Struthio camelus) trypsinogen genes was cloned from pancreatic cDNA. Its amino acid sequence compared to known trypsin sequences from other species shows high identity and suggests that it is a member of the phylogenetically anionic trypsinogen I subfamily. After cytoplasmic over expression in Escherichia coli and renaturation, the activation properties of ostrich trypsinogen were studied and compared to those of human trypsinogen 1 (also called as human cationic trypsinogen). Ostrich trypsinogen undergoes bovine enterokinase activation and autoactivation much faster than human trypsinogen 1 and exhibits on a synthetic substrate a somewhat higher enzymatic activity than the latter one. The most interesting property of ostrich trypsin is its relatively fast autolysis that can be explained via a mechanism different from the common mechanism for rat and human 1 trypsins. The latter proteases have a site, Arg117-Val118, where the autolysis starts and then goes on in a zipper-like fashion. This is absent from ostrich trypsin. Instead it has a couple of cleavage sites within regions 67-98, including two unusual ones, Arg76-Glu77 and Arg83-Ser84. These appear to be hydrolysed fast in a non-consecutive manner. Such an autolysis mechanism could not be inhibited by a single-site mutation which in humans is proposed to lead to pancreatitis. 相似文献
62.
The morphin-analogue, Durogesic, has robust analgetic effect without repeated side-effects and is suitable for special applications providing it as the first choice for therapy of cancer pain and as an acceptable alternative for CR morphin. Clinical studies not only provided evidences for the pharmacological effectivity of Durogesic but suggested that the quality of life of cancer patients improved significantly as well. 相似文献
63.
64.
Since the vigilance states of the rat can be largely controlled by one hour light-one hour dark cycles, we investigated the effect of this photoperiod on the rat brain indoles and motor activity. Groups of 9 rats were killed 15-20 min or 45-50 min after the onset of the 1-hour light or 1-hour dark period. Serotonin (5HT) and 5-hydroxyindoleacetic acid were determined fluorometrically in cortex, hypothalamus and brain stem. Tryptophan was determined fluorometrically in serum, cortex and hypothalamus. Cortical tryptophan was highest at the end of the dark period, whereas cortical 5-HT and 5-hydroxyindoleacetic. acid were highest at the beginning of the light period. Motor activity was high during darkness and low during light. When the biochemical results were compared to the motor activity records of the individual animals, the decrease in motor activity at the onset of light correlated significantly with the cortical 5-hydroxyin- doleacetic acid/5-HT ratio in the animals killed at the beginning of the light period. The results indicate a rapid response of the cortical indoles to the onset of light and support the hypothesis that the induction of sleep is related to the brain indole metabolism. 相似文献
65.
Anna Kis Melinda Bence Gabriella Lakatos Enik? Pergel Borbála Turcsán Jolanda Pluijmakers Judit Vas Zsuzsanna Elek Ildikó Brúder Levente F?ldi Mária Sasvári-Székely ádám Miklósi Zsolt Rónai Enik? Kubinyi 《PloS one》2014,9(1)
The oxytocin system has a crucial role in human sociality; several results prove that polymorphisms of the oxytocin receptor gene are related to complex social behaviors in humans. Dogs'' parallel evolution with humans and their adaptation to the human environment has made them a useful species to model human social interactions. Previous research indicates that dogs are eligible models for behavioral genetic research, as well. Based on these previous findings, our research investigated associations between human directed social behaviors and two newly described (−212AG, 19131AG) and one known (rs8679684) single nucleotide polymorphisms (SNPs) in the regulatory regions (5′ and 3′ UTR) of the oxytocin receptor gene in German Shepherd (N = 104) and Border Collie (N = 103) dogs. Dogs'' behavior traits have been estimated in a newly developed test series consisting of five episodes: Greeting by a stranger, Separation from the owner, Problem solving, Threatening approach, Hiding of the owner. Buccal samples were collected and DNA was isolated using standard protocols. SNPs in the 3′ and 5′ UTR regions were analyzed by polymerase chain reaction based techniques followed by subsequent electrophoresis analysis. The gene–behavior association analysis suggests that oxytocin receptor gene polymorphisms have an impact in both breeds on (i) proximity seeking towards an unfamiliar person, as well as their owner, and on (ii) how friendly dogs behave towards strangers, although the mediating molecular regulatory mechanisms are yet unknown. Based on these results, we conclude that similarly to humans, the social behavior of dogs towards humans is influenced by the oxytocin system. 相似文献
66.
Turiák L Misják P Szabó TG Aradi B Pálóczi K Ozohanics O Drahos L Kittel A Falus A Buzás EI Vékey K 《Journal of Proteomics》2011,74(10):2025-2033
Several studies have characterized exosomes derived from different cell sources. In this work we set the goal of proteomic characterization of two less studied populations of membrane vesicles, microvesicles (100-800 nm) and apoptotic bodies (> 800 nm) released by thymus cells of BALB/c mice. The vesicles were isolated by the combination of differential centrifugation and gravity driven multistep filtration of the supernatant of thymus cell cultures. The size distribution of vesicle preparations was determined by transmission electron microscopy. Proteins were released from the vesicles, digested in solution, and analyzed using nano-HPLC/MS(MS). Ingenuity pathway analysis was used to identify functions related to membrane vesicle proteins. In apoptotic bodies and microvesicles we have identified 142 and 195 proteins, respectively. A striking overlap was detected between the proteomic compositions of the two subcellular structures as 108 proteins were detected in both preparations. Identified proteins included autoantigens implicated in human autoimmune diseases, key regulators of T-cell activation, molecules involved in known immune functions or in leukocyte rolling and transendothelial transmigration. The presence and abundance of proteins with high immunological relevance within thymocyte-derived apoptotic bodies and microvesicles raise the possibility that these subcellular structures may substantially modulate T-cell maturation processes within the thymus. 相似文献
67.
Dr. Vincenz v. Borbás 《Plant Systematics and Evolution》1891,41(9):320-323
Ohne Zusammenfassung 相似文献
68.
Vincentio de Borbás 《Plant Systematics and Evolution》1876,26(3):88-90
Ohne Zusammenfassung 相似文献
69.
v. Borbás 《Plant Systematics and Evolution》1875,25(6):206-208
Ohne Zusammenfassung 相似文献
70.
Dr. Vincenz v. Borbás 《Plant Systematics and Evolution》1894,44(10):397-400
Ohne Zusammenfassung 相似文献