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1.
The expression of CEA was studied with the help of rabbit antibody and CEA-specific lectin-krustacin in pepsinogen positive gastric glands near carcinomas and in gastric mucosa with intestinal metaplasia and dysplasia of the epithelium without neoplasia. CEA-krustacin was revealed in 20 out of 41 cases and CEA-antibody in 2 out of 41 cases of gastric glands in mucosa near carcinomas. The results of investigation discover the development in the gastric glands near carcinoma subcellular components. Paraneoplastic phenomenon was found in the majority of the cases.  相似文献   
2.
KV Thomas 《Biofouling》2013,29(1):73-86

Antifouling paint booster biocides are a group of organic compounds added to antifouling paints to improve their efficacy. They have become prevalent since the requirement for alternative antifouling paints formulations for small boats (< 25 m). This need followed a ban on the use of triorganotin biocides in antifouling paints for small boats, in the late 1980's. Worldwide, around eighteen compounds are currently used as antifouling biocides, viz. benzmethylamide, chlorothalonil, copper pyrithione, dichlofluanid, diuron, fluorofolpet, Irgarol 1051, Sea‐Nine 211, Mancozeb, Polyphase, pyridine‐triphenyl‐borane, TCMS (2,3,5,6‐tetrachloro‐4‐methylsulfonyl) pyridine, TCMTB [2‐(thiocyanomethylthio)benzothia‐zole], Thiram, tolyfluanid, zinc pyrithione (ZPT), ziram and Zineb. Any booster biocide released into the environment is subjected to a complex set of processes. These processes include transport mechanisms, transformation, degradation, cross media partitioning, and bioaccumulation. This paper reviews the fate and behaviour data currently available in the public domain concerning antifouling paint booster biocides.  相似文献   
3.
A series of 13 phosphonium salts on the basis of pyridoxine derivatives were synthesized and their antibacterial activity against clinically relevant strains was tested in vitro. All compounds were almost inactive against gram-negative bacteria and exhibited structure-dependent activity against gram-positive bacteria. A crucial role of ketal protection group in phosphonium salts for their antibacterial properties was demonstrated. Among synthesized compounds 5,6-bis[triphenylphosphonio(methyl)]-2,2,8-trimethyl-4H-[1,3]dioxino[4,5-c]pyridine dichloride (compound 20) was found to be the most effective towards Staphylococcus aureus and Staphylococcus epidermidis strains (MIC 5 μg/ml). The mechanism of antibacterial activity of this compound probably involves cell penetration and interaction with genomic and plasmid DNA.  相似文献   
4.

Background

The function of proteins is a direct consequence of their three-dimensional structure. The structural classification of proteins describes the ways of folding patterns all proteins could adopt. Although, the protein folds were described in many ways the functional properties of individual folds were not studied.

Results

We have analyzed two β-barrel folds generally adopted by small proteins to be looking similar but have different topology. On the basis of the topology they could be divided into two different folds named SH3-fold and OB-fold. There was no sequence homology between any of the proteins considered. The sequence diversity and loop variability was found to be important for various binding functions.

Conclusions

The function of Oligonucleotide/oligosaccharide-binding (OB) fold proteins was restricted to either DNA/RNA binding or sugar binding whereas the Src homology 3 (SH3) domain like proteins bind to a variety of ligands through loop modulations. A question was raised whether the evolution of these two folds was through DNA shuffling.  相似文献   
5.
High values of dominance index, low values of evenness and Shannon index are characteristic of component parasite communities of prespawning (Prosopium cylindraceum) and spawn migratory fishes (Coregonus autumnalis, Oncorhynchus nerka). Autogenic specialists are dominant in the component parasite communities of C. autumnalis. The component parasite communities of P. cylindraceum and O. nerka are dominant in a content of generalist species. The O. nerka parasite communities are communities "sentenced to death". Low values of dominance index, high values of evenness abd Shannon index are peculiar to component parasite communities of prespawning and spawning cyprinid fishes (Phoxinus phoxinus, Oreoleuciscus humilis). Autogenic specialists are dominant. Increase of dominance index and decrease of two other indexes characterize the postspawning period. The same tendency characterises infracommunities. Thus, the component parasite communities respond differently to the fish spawn of the cyprinid and coregonid/salmonid fishes. Similarity is in the dominance of autogenic specialists in one case only (C. autumnalis). These differences are defined by the mode of fish stock formation for spawn. The cyprinids congregate for spawning and move apart for foraging and vice versa is observed in the coregonids and salmonids. Autogenic specialists dominance seems to be the important adaptation to reduce a negative effect to host during spawning. Bush and Kennedy in 1994 established that "parasites live in patches (host individuals) and fragments (host populations)". They consider the host fragmentation as "hedging your bets against extinction" due to frequency and magnitude anthropogenic factors, which increase fragmenting of host populations. This conclusion was made for a species level. From the other hand the fragmentation is a natural feature for a single host population too. Such fragmentation is a host population structure. The role of fragmentation is obvious from the data on component parasite communities during fish spawn. The fragmentation decreases in the cyprinids and increases in the salmonids that leads to the growing of the cyprinid component parasite communities diversity and to declining the salmonid component parasite communities diversity. Nevertheless the role of host population structure in a component parsite community structure is not obvious, because parasites are able or not able to "recognise" different host subpopulation groups. It is well known from data on parasite species population biology. Such recognizable subpopulation groups or groups can be a "real fragment" for the parasite community. The question is what parameters could be used for this purpose on a component community level. Host population age structure can be used as an example, because the age groups are one of the invariable population characters. Value of Shannon index for component parasite communities of spawn migratory O. nerka (5+) is similar to that of fishes of 1+ age. Difference is statistically insignificant. It is insignificant between the parasite communities of 2+ and 3+ age groups too. Fishes of these two groups could be defined as a real united fragment. It spite of similarity between the fishes of 5+ age group and fish of 1+ age group they are not united fragment. The parasite community of 1+ age fishes is not stabilized yet and one of 5+ age is a community "sentenced to death". Thus the structuring of O. nerka freshwater parasite communities are defined by 3 real host age fragments: 1+ age group, 2 and 3+ age group, 4+ age group. It looks as that Shannon index is suitable parameter to study a parasite communities structure.  相似文献   
6.
Polymerase-chain-reaction-based restriction fragment length polymorphism analysis was performed to establish genetic markers in rDNA, for the identification of the three sibling species of the Anisakis simplex complex and morphologically differentiated Anisakis species, i.e. Anisakis physeteris, Anisakis schupakovi, Anisakis typica and Anisakis ziphidarum. Different restriction patterns were found between A. simplex sensu stricto and Anisakis pegreffii with two of the restriction endonucleases used (HinfI and TaqI), between A. simplex sensu stricto and A. simplex C with one endonuclease (HhaI), and between A. simplex C and Aniskis pegreffii with three endonucleases (HhaI, HinfI and TaqI), while no variation in patterns was detected among individuals within each species. The species A. physeteris, A. schupakovi, A. typica and A. ziphidarum were found to be different from each other and different from the three sibling species of the A. simplex complex by distinct fragments using 10-12 of the endonucleases tested. The polymorphisms obtained by restriction fragment length polymorphisms have provided a new set of genetic markers for the accurate identification of sibling species and morphospecies.  相似文献   
7.
Two possible forms of tick-borne encephalitis virus (TBE) gene NS1 (called NS1' and NS1) were constructed using two overlapping cDNA-fragments of TBE genome and synthetic DNA fragments. This genes were expressed in E. coli cells in expression vector pUR290 as individual proteins or fusion with bacterial beta-galactosidase. The proteins NS1 (Mw. 39 kDa), beta-galactosidase-NS1' (Mw. 162 kDa) and beta-galactosidase-NS1 (Mw. 155 kDa) were effectively synthesized under the Plgc-promoter induction conditions. Expression of NS1' gene results in the formation of two virus-specific proteins (Mw. 46 and 44 kDa). All bacterial analogs of NS1 protein fixed monoclonal and polyclonal antibodies specific to viral NS1.  相似文献   
8.
Effects of single intranasal administration of 0.2 ng insulin at different moments of the projected daily cycle (ZT = 1, ZT = 7, ZT = 13 and ZT = 19) on the circadian rhythms of voluntary locomotor activity (wheel-running) were studied in Wistar male rats. Insulin administered at ZT-7 or ZT-13 induced a statistically significant phase advance by 4.4 and 5.5 hours, respectively. The administration of insulin at ZT-13 additionally induced a reduction of the period of the circadian rhythm of voluntary locomotor activity. Intranasal administration of insulin at other moments of the projected daily cycle (ZT = 1 or ZT = 19) did not induce any statistically significant change in phase or period duration of the circadian rhythms. Insulin did not cause changes in total daily activity irrespective of administration time. The results of the study suggest the role of endogenous insulin as entrainment factor for circadian oscillator in absence of the main physiological zeitgeber--cyclic afferent input from retina photoreceptors.  相似文献   
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