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Intestinal injury can be reduced by intra-arterial postischemic perfusion with hypertonic saline

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World Journal of Gastroenterology 2013年第2期19卷 209-218页

作者： oleg Kornyushin Michael Galagudza anna Kotslova Gelfia Nutfullina Nina Shved Alexey Nevorotin Valeriy sedov.Timur Vlasov Department of Surgery I.P.Pavlov Federal Medical University197022 St.PetersburgRussia Department of Pathophysiology I.P.Pavlov Federal Medical University197022 St.PetersburgRussia Institute of Experimental Medicine V.A.Almazov Federal HeartBlood and Endocrinology Centre197341 St.PetersburgRussia Department of Pathology I.P.Pavlov Federal Medical University197022 St.PetersburgRussia Laboratory of Electron Microscopy I.P.Pavlov Federal Medical University197022 St.PetersburgRussia

AIM:To investigate the effect of local intestinal perfusion with hypertonic saline(HTS) on intestinal ischemia-reperfusion injury(IRI) in bothex vivo andin vivo rat ***:All experiments were performed on male Wistar rats anesthetized with pentobarbital sodium given intraperitoneally at a dose of 60 mg/*** vivo vascularly perfused rat intestine was subjected to 60-min ischemia and either 30-min reperfusion with isotonic buffer(controls),or 5 min with HTS of 365 or 415 mosm/L osmolarity(HTS 365mosm or HTS 415mosm,respectively) followed by 25-min reperfusion with isotonic *** vascular intestinal perfusate flow(IPF) rate was determined by collection of the effluent from the portal vein in a calibrated *** intestinal contraction rate was monitored *** intestinal injury or area of necrosis(AN) was evaluated histochemically using 2.3.5-triphenyltetrazolium chloride *** vivo,30-min ischemia was followed by either 30-min blood perfusion or 5-min reperfusion with HTS 365mosm through the superior mesenteric artery(SMA) followed by 25-min blood *** blood pressure(BP) was measured in the common carotid artery using a miniature pressure *** injury was evaluated in both preparations using the Chui ***:Ex vivo,intestinal IRI resulted in a reduction in the IPF rate during reperfusion(P ostischemic recovery of the IPF rate did not differ between the controls and the HTS 365mosm *** the HTS 415mosm group,postischemic IPF rates were lower than in the controls and the HTS 365mosm group(P ontraction rate was similar at baseline in all *** increase in this parameter was observed during the first 10 min of reperfusion in the control group as compared to the sham-treated group,but no such increase was seen in the HTS 365mosm *** controls,AN averaged 14.8% ± 5.07% of the total tissue *** of HTS 365mosm for 5 mi

关键词： Intestinal ischemia-reperfusion injury Superior mesenteric artery Perfusion Hypertonic saline Acute mesenteric ischemia Intestinal perfusate flow rate

Trends and rates of holocene soil evolution in the North Caucasian Piedmont

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Chinese Science Bulletin 1999年第S1期44卷 193-199页

作者： A.L.ALEXANDRoVSKY S.N.sedov.A.A.GoLYEVA Institute of Geography of RAS 109017 Staromonetnyi per. 29 Moskow Russia Dep. of Soil Science Moscow Lomonosov University 119899 Moscow Russia

In the piedmont of the North Caucasus a 3500 yr B.P. steppe was replaced by forest asclimate became moister. Steppe Chernozems were preserved under high (up to 8 m) burial mounds(kurgans) constructed about 5000 yr B.P. on natural landsurfaces surrounding the kurgans,Chernozems evolved to Luvisols. on the kurgans made of loess and Chernozem soil, matureLuvisols formed during the forest stage. on the kurgans covered with artificial limestone paving,the Luvisol profile is less developed. Migration and transformation of substances occur throughoutthe whole kurgan pile. These include fissures and earthworm channels filled with clay-humusmaterial or secondary carbonates, gleyed mottles, iron oxides, and neoformed gypsum. Theseprocesses cause diagenetic transformation of buried Chernozems even at depth.

关键词： caucasian piedmont burial mounds Chernozems luvisols soil and landscape evolution holocene

The simulation of ultrasonic beams with a Gaussian beam equivalent point source model

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Chinese Journal of Acoustics 2010年第2期29卷 97-106页

作者： SCHMERR L W HUANG R sedov.A Center for NDE Iowa State University Ames Department of Mechanical Engineering Lakehead University Thunder Bay

Point Sources and Gaussian beams are used frequently as fundamental building blocks for developing ultrasonic beam models. Both these models have different weaknesses that limit their effectiveness. Here, we will show that one can develop a Gaussian Beam Equivalent Point Source （GBEPS） model that removes those weaknesses and combines the accuracy and versatility of the point source models with much of the speed and well-behaved nature of Gaussian beam models. We will demonstrate the efficiency and versatility of this new GBEPS model in simulating the beams generated from ultrasonic phased arrays, using as few as one Gaussian beam per element of the array. A single element GBEPS model will be shown to be as accurate as a point source model even when substantial beam focusing or steering is present in the array or where the array beam is transmitted through an interface. At the same time the GBEPS model will be shown to be several orders of magnitude faster than the point source model.

关键词： The simulation of ultrasonic beams with a Gaussian beam equivalent point source model very exp

Late holocene man-induced environmental change in central russian plain: paleopedological evidences from early-medieval archaeological site.

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Chinese Science Bulletin 1999年第S1期44卷 159-165页

作者： S.N.sedov.E.P.ZAZoVSKAYA M.A.BRoNNIKoVA A.A.KAZDYM S.Yu.RoZoV Department of Soil Science Lomonosov University Moscow Russia.

Local natural and man-induced environmental changes in the early medievalarchaeological site in the central Russian plain were reconstructed by study of surface and buriedsoil profiles. Natural soils and ecosystems on watersheds were similar to present ones in agreementwith palynological data. In the floodplain there are remains of forest soils and anthropogenichorizons. These formed in ancient urban environments and are buried under recent alluviumindicating that alluvial sedimentation and flood intensities were much less than at present. Ancientman-induced environmental change related to crop growing activity is well documented bypalynological data but corresponding cultivated horizons are found only in few buried profiles,being unstable if left on the surface. Paleopedological signs of the ancient urban environment arevery stable and preserved in surface soils even 1000 years after the settlement stopped functioning.

关键词： Central Russian plain late Holocene anthropogenic soil properties Micromorphology man-induced environmental change

Man-Induced Landscape Evolution in the North Caucasian Piedmont of Russia

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Chinese Science Bulletin 1999年第S1期44卷 166-172页

作者： S.N.sedov.M.I.SKRIPNIKoVA Yu.N.VoDYANITZKY I.V.TURoVA M.A.BRoNNIKoVA Department of Soil Science Moscow Lomonosov University Moscow. Russia Dokuchaev Soil Institute Moscow Russia

Paleosols buried by colluvial deposits and artificial agricultural terraces wereinvestigated to reconstruct natural and man-induced environmental change in the central NorthCaucasus. The profiles buried under ancient man-made agricultural terraces (1000-1500 years B.P.)are similar to recent surface Chemozems. Minor differences in thickness, humus and carbonatecontent of Ah horizons are due to anthropogenic disturbance before burial or diagenesis. Thisindicates that a steppe ecosystem persisted in the central North Caucasian piedmont during lateHolocene. The sections of colluvial sediments in downslope positions show alternation of coarsestony slope deposits and well developed though truncated paleosol profiles. This indicates thatperiods of soil formation and low activity of colluviation alternated with dramatic intensificationof mass movement on slopes. The early medieval anthropogenic deforestation may havedestabilised slopes and activated development of the upper layer of the coarse *** related to ancient cultivation were detected in the paleosol below this layer.

关键词：三言卫生电声