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To investigate the effects of gravel content on runoff and sediment yield on Lou soil accumulation slopes, we conducted indoor simulation rainfall experiments and examined the characteristics of runoff and sediment yield on accumulation slopes with five gravel contents (10%, 20%, 30%, 40%, 50%) under four rainfall intensities (1.0, 1.5, 2.0, 2.5 mm·min -1 ), with a no gravels slope as control. The average runoff rate under different test conditions ranged from 2.18 to 13.07 L·min -1 . The average runoff rate was the maximum under the gravel content of 10% (or 20%) and the minimum under the 50% gravel content. The average flow velocity ranged from 0.06 to 0.22 m·s -1 . The variation of flow velocity was complex. The smaller the gravel content, the larger the range of variation and the coefficient of variation. The average flow velocity reached the maximum when the gravel content was 10%. The presence of gravel effectively inhibited the sediment yield, and the sediment reduction benefit reached 84.2%. The rainfall intensity had more influence on the average sediment yield rate than gravel content. Results of partial correlation analysis showed that gravel content was significantly negatively correlated with the ave-rage runoff rate, the average flow velocity, and the average sediment yield rate. The relationships between the ave-rage sediment yield and the average runoff rate, the average flow velocity, and their interaction were all extremely significant linear functions, with the strongest relationship between the average sediment yield and the average runoff rate. This study could provide references for the control of soil erosion and the establishment of erosion models for engineering accumulations in Lou soil areas.

Objective: To establish a method for extracting Listeria monocytogenes membrane vesicles (LM-MVs) and to analyze the characteristics of LM-MVs and their ability to induce innate immune effect in vitro so as to lay the foundation for research into using LM-MVs as vaccine carrier and drug delivery platform., Methods: The membrane vesicles secreted by Listeria monocytogenes were extracted through a continuous process, including culturing, centrifugation, filtration, ultrafiltration concentration and ultracentrifugation. The morphological characteristics of LM-MVs were observed with transmission electron microscope, and particle size distribution were measured by dynamic light scattering analysis. SDS-PAGE and Western blot were used to analyze the protein composition of LM-MVs. CCK-8 cell proliferation and toxicity determination experiments were done to analyze their effect on the proliferation of innate immune cells, and qPCR was used to analyze their ability to induce innate immune responses., Results: A method for extracting LM-MVs was successfully established. Under the transmission electron microscope, LM-MVs presented a nearly circular film-like structure, and dynamic light scattering analysis showed that their sizes were between 65 and 190 nm. SDS-PAGE and Western blot showed that LM-MVs contained proteins, including listeriolysin O (LLO). CCK-8 cell proliferation and toxicity experiment showed that after intervention with 10, 20 and 50 μg/mL of LM-MVs for 24 hours, the proliferation rate of DC 2.4 mouse dendritic cell line was higher than that of non-interventional DC 2.4 cells ( P <0.05); after intervention with 0.1, 1, 10, 20 and 50 μg/mL of LM-MVs for 24 hours, the proliferation rate of RAW 264.7 cells was higher than that of non-interventional RAW 264.7 cells ( P <0.01). The results of qPCR showed that, after intervention with 50 μg/mL of LM-MVs, the expression levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-10 in RAW 264.7 cells were higher than those of non-intervention control cells ( P <0.05)., Conclusions: The method established in the study can be used to extract LM-MVs. The extracted LM-MVs have a diameter of 65-190 nm and a nearly circular membrane-like structure. They can secrete a variety of protein components and stimulate innate immune responses., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).)

Reducing the application of chemical fertilizer and increasing fertilizer efficiency can contribute to the sustainable development of agriculture. To evaluate the impacts of N fertilizer reduction and biochar application on soil organic carbon active components and mineralization in yellow soil, an experiment was carried out with five different substitution rates of chemical N fertilizer by biochar under the same rate of N input, i.e ., 0, 10%, 20%, 30%, 40% (CK, T 1 -T 4 ). The results showed that chemical N fertilizer reduction combined with biochar application could significantly improve soil organic carbon (SOC), the magnitude of which was proportional to the amount of biochar application. Under the condition of 20% substitution rate (T 2 ), soil microbial biomass carbon (MBC) and readily oxidized carbon (ROC) were the highest with 293.68 mg·kg -1 and 250.00 mg·kg -1 , respectively, but the concentration of soil dissolved organic carbon (DOC) was the lowest. SOC mineralization rate reached the highest on the third day of incubation. Then, it decreased rapidly in the early period (day 3 of incubation to day 6), decreased slowly in the middle period (day 6 of incubation to day 18), and stabilized in the later period (day 18 of incubation to day 30). There was a logarithmic relationship between mineralization rate of soil organic carbon and incubation time. SOC cumulative mineralization amount and cumulative mineralization rate were the lowest in the T 2 treatment with 0.66-0.86 g·kg -1 and 2.9%-4.0%, respectively. As the substitution rate of chemical N fertilizer by biochar increased, rice yield increased firstly and then decreased. Rice yield in the T 2 treatment was the highest, which increased by 13.4% compared with the CK. The substitution of 20% chemical N fertilizer with biochar (5 t·hm -2 ) could effectively improve the contents of SOC, MBC, ROC, and rice yield, reduce the cumulative mineralization amount of organic carbon and cumulative mineralization rate, and enhance the capacity of soil carbon sequestration. Hence, it could be the most effective fertilizer practice for improving soil fertility and rice yield in paddy field of yellow soil in Guizhou Province.

Forests play an important role in terrestrial carbon cycles. The mechanism underlying carbon balance in temperate deciduous broad-leaved forests is not clear. In this study, net ecosystem exchange (NEE) and environmental factors, including air temperature ( T a ), soil temperature ( T s ), photosynthetically active radiation (PAR), vapor pressure deficit (VPD), soil water content (SWC) and precipitation ( P ) were continually measured using eddy covariance techniques in 2019 in a deciduous broad-leaved forest in Songshan, Beijing. We analyzed the characteristics of NEE and its response to environmental factors. The results showed that, at diurnal scale, the monthly averaged NEE exhibited a "U" shape curve ( i.e ., being a carbon sink over daytime while being a carbon source during nighttime) over the growing season. During the non-growing season, NEE was positive ( i.e ., carbon source) at diurnal scale. At the seasonal scale, NEE exhibited a unimodal curve. The annual cumulative NEE was -111 g C·m -2 ·a -1 . Annual ecosystem respiration was 555 g C·m -2 ·a -1 , while gross ecosystem productivity was 666 g C·m -2 ·a -1 . Carbon sequestration peaked in June, while emission peaked in November. PAR was the dominant factor affecting daytime NEE (NEE d ). VPD was the main factor that indirectly affected daytime NEE d , with an optimal VPD value that maximizes daytime NEE around 1-1.5 kPa. Soil temperature was the main factor affecting nighttime NEE (NEE n ). SWC was a limiting factor for NEE n . Too high or too low SWC would inhibit NEE n , with an optimal SWC value of 0.28 m 3 ·m -3 .

Sewage sludge is rich in organic matter, N, and P and could be used as a soil amendment to improve the status of soil organic matter, soil structural characteristics, and soil water retention capacity after aerobic composting. However, heavy metals in sewage sludge have become the main bottleneck limiting its land application. In addition, with the large-scale exploitation of phosphate rock resources in our region of interest, a large amount of phosphate tailings needs to be disposed and a large area of abandoned mining lands needs to be reclaimed. Phosphate tailings could be auxiliary materials for sewage sludge composting to immobilize heavy metals, and the compost could be applied for revegetation of the abandoned mining lands. The contents of As, Cr, Cu, Ni, Pb, Cd, and Zn were measured, and a successive extraction procedure was used to investigate the change in speciation of heavy metals in the sludge before and after the phosphate-rich composting. pH-dependent leaching tests were carried out to further evaluate the immobilization effects of composting on heavy metals and the release potential under different pH conditions. The results showed that the contents of heavy metals in the compost satisfied the corresponding threshold for land reclamation. Adding phosphate tailings greatly improved the stability of heavy metals during the composting process. The portion of stable residues of Pb, Cd, As, and Zn in the phosphate-rich compost was 84.00%, 58.00%, 68.50%, and 30.93%, respectively, compared with 68.10%, 30.50%, 40.32%, and 16.48% for the control, compost without adding the phosphate tailings. Meanwhile, the maximum leaching potential of As, Ni, Pb, Zn, and Cu in the phosphate-rich compost decreased from 3.692 mg·kg -1 , 0.903 mg·kg -1 , 0.217 mg·kg -1 , 7.225 mg·kg -1 , and 8.725 mg·kg -1 to 0.684 mg·kg -1 , 0.586 mg·kg -1 , 0.071 mg·kg -1 , 2.603 mg·kg -1 , and 6.935 mg·kg -1 in the control, respectively, for pH 6-8.It could be concluded that the addition of phosphate tailings in the sludge composting lowered the risk of heavy metals in sewage sludge compost to make it favorable for beneficial use in abandoned mining land reclamation.

Fly ash from sludge incineration was separated into five different sizes (<1 μm, 1-2.5 μm, 2.5-10 μm, 10-50 μm, and > 50 μm) by high-precision air classification equipment. The leaching of heavy metals was contrastively studied using the HJT 299-2007-sulfuric acid/nitric acid method, HJ 557-2009-Horizontal Oscillation Method, toxicity characteristic leaching procedure (TCLP), and European standard protocol (EN 12457-3) for the different size fractions of the fly ash. Based on the leaching results, an evaluation method for the comprehensive toxicity of heavy metal leaching was established. The results show that the content of heavy metals and the amount of leaching from the fly ash decrease with the increase in fly ash particle size. The leaching of the heavy metals Zn and Cu in the < 1 μm particle size range of TCLP leaching method was the highest, at 107.34 mg·kg -1 and 318 mg·kg -1 , respectively. The TCLP and sulfuric acid/nitric acid methods of heavy metal leaching were more effective than the EU (EN 12457-3) and horizontal oscillation methods. According to the value of OPTI, the OPTI value of < 10 μm fly ash was much larger than that of fly ash that was > 10 μm. This indicated that the fly ash of particle size < 10 μm was more toxic and more harmful.

Objective: To study the spatiotemporal distribution of Oncomelania hupensis snails in different areal-types at a village level in Hubei Province, so as to provide the basis for formulating the strategies and measures of snail control., Methods: The snail data of 30 schistosomiasis epidemic counties at a village scale in Hubei Province from 2007 to 2012 were collected and combined with the geographic information of each village to construct the spatial database of snails. The snail area and its change trend of different areal-types were illustrated; the multilevel model of snail distribution was established., Results: The snail area of each village from 2007 to 2012 was correlated (Intra-class correlation coefficient, ICC = 95.7%). Both the baseline and the rate of change of snail area were significantly different (σ(2)(u0) = 4,766.53, σ(2)(u1)= 20.96, both P < 0.01). The rate of change of snail area was higher if the baseline of snail area was higher (σ(2)(u01) =126.78, P < 0.01). The snail areas of villages were increased slowly by year (year = 0.64,P < 0.01). The average snail areas and growth of snail areas of villages in the marshland and lake region were largest (type= -29.84, P < 0.01; year*type = -0.52, P < 0.01)., Conclusions: The snail area is significantly different among both villages and areal-types. This study spatially visualizes the snail data of 30 schistosomiasis epidemic counties in Hubei Province and establishes the multilevel model, providing the basis of snail control in different areal-types.

The effects of nitrogen fertilization or nitrogen deposition on soil greenhouse gases fluxes has been well studied, while little has been piloted about the effects of nitrogen application on soil greenhouse gas fluxes and its discrepancy with different soil organic carbon content. In our study, we conducted field control experiment in a young Eucalyptus plantation in Southeast China. We compared the effects of 4 levels of nitrogen fertilization (Control: 0 kg · hm(-2); Low N: 84.2 kg · hm(-2); Medium N: 166.8 kg · hm(-2); High N: 333.7 kg · hm(-2)) on soil GHGs fluxes from 2 sites (LC and HC) with significantly different soil organic carbon (SOC) content (P < 0.05). The results showed: (1) Fertilization had significant priming effect on CO2 and N2O emission fluxes. One month after fertilization, both CO2 and N2O had the flux peak and decreased gradually, and the difference among the treatments disappeared at the end of the growing season. However, fertilization had no significant effect on CH4 oxidation between the 2 sites. (2) Fertilization and SOC were two crucial factors that had significant effects on CO2 and N2O emission. Fertilization had a significant positive effect on CO2 and N2O emission fluxes (P < 0.001). CH4 oxidation rates decreased with the increasing N addition, but there was no statistical difference (P > 0.05). The CO2 and N2O emission fluxes were significantly higher in HC than those in LC (P < 0.01). (3) Fertilization and SOC had great interactive effect on CO2 and N2O emission (P < 0.05). Compared with fluxes in LC, the fluxes in HC were much more sensitive to N input: low N could remarkably stimulate the CO2 and N2O emission. In conclusion, the effects of nitrogen fertilization on soil GHGs fluxes were not only in connection with the intensify of nitrogen, but also closely tied to the SOC content. When we assess the effects of nitrogen on soil GHGs fluxes, the difference induced by SOC should not be ignored.

Objective: To investigate the in vitro protective effect of Pinus massoniana bark extracts (PMBE) against cisplatin-induced nephrotoxicity in human embryonic kidney cells (HEK293), and preliminarily study its mechanism., Method: Human embryonic kidney cells (HEK293) were cultured in vitro. The MTT assay was adopted to test the effect of PMBE and cisplatin on growth of HEK293 cells, and the protective effect of PMBE on cisplatin-induced nephrotoxicity of HEK293, and then detect the intracellular reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH) content, catalase (CAT), superoxide dismutase (SOD) and activity of thioredoxin reductase (TrxR)., Result: PMBE could promote growth of HEK293 cells at low concentrations, but generate slight nephrotoxicity at high concentration. Cisplatin could inhibit growth of HEK293 cells, increase ROS and MDA content, while reducing SOD, CAT and TrxR. The pre-protective PMBE was added to reduce cisplatin's injury to HEK293 cells, ROS, MDA and GSH content, SOD, CAT and TrxR within certain range., Conclusion: PMBE at specific concentration has the protective effect in cisplatin-induced nephrotoxicity in HEK293 cells. Its mechanism may be related to PMBE's antioxidant activity.

Objective: To study the influence of superfine grinding technology on extracting flavones from plantain and explore its optimum extraction technology., Methods: Ultrasonic technology was used to extract the flavones in superfine grinding plantain, the content of flavone glycosides was determined by RP-HPLC., Results: The optimum technology was as follows: the concentration of ethanol was 60%, temperature was 60 degrees C, solid-liquid ratio (g:mL) was 1:20 and extraction time was 20 min. Under these conditions, flavonoids extraction rate of superfine grinding powder was higher than that of conventional powder., Conclusion: The technology of superfine grinding can improve flavonoids extraction rate in plantain. An optimum method for extracting flavonoids from superfine granding plantain is established.

Objective: To test the effect of recombinant interleukin-4 (IL-4) and recombinant osteoprotegerin (OPG) in suppressing bone resorption induced by polyethylene wear particles.., Methods: A cranial bone allograft was introduced into the air pouches induced on the back of BALB/c mice, followed by injection of 1 ml suspension of polyethylene particles into the pouches. The mouse models were then divided into 3 groups to receive injections of saline (control), IL-4 alone, or IL-4 and OPG into the pouches. The tissues were harvested 21 days after bone implantation for molecular and histological analyses., Results: Polyethylene wear particles-stimulated inflammatory responses (increased cellular infiltration and IL-1 and TNF production) were markedly reduced by IL-4 treatment either alone or combined with OPG (P<0.05). Polyethylene particles significantly increased tartrate-resistant acid phosphatase (TRAP) staining and bone absorption of the implanted bone graft, and IL-4 treatment, either alone or combined with OPG, obviously reduced the osteolysis induced by polyethylene particles (P<0.05)., Conclusion: IL-4 offers protection against polyethylene wear debris-induced inflammation and bone resorption in this mouse model. IL-4 combined with OPG can be a feasible and effective therapeutic approach to the treatment and prevention of polyethylene wear debris-associated osteolysis and aseptic loosening of the prosthetic components.

The high water content of sewage sludge has engendered many inconveniences to its treatment and disposal. While ultrasonic takes on unique advantages on the sludge drying because of its high ultrasonic power, mighty penetrating capability and the ability of causing cavitations. Thus this research studies the characteristics influences of ultrasonic bring to the sludge drying and effects of the exposure time, ultrasonic generator power, temperatures of ultrasonic and drying temperature on the drying characteristics of dewatered sludge. Results indicate that ultrasonic pretreatment could speed up evaporation of the free water in sludge surface and help to end the drying stage with constant speed. In addition, ultrasonic treatment can effectively improve the sludge drying efficiency which could be more evident with the rise of the ultrasonic power (100-250 W), ultrasonic temperature and drying temperature. If dried under low temperature such as 105 degrees C, sludge will have premium drying characteristics when radiated under ultrasound for a shorter time such as 3 min. In the end, the ultrasonic treatment is expected to be an effective way to the low-cost sludge drying and also be an important reference to the optimization of the sludge drying process because of its effects on the increase of sludge drying efficiency.

An experimental work was carried out to investigate the effect of additives (clay and coal fly ash) and washing-pretreatment on the stabilization of critical heavy metals (Cd, Cu, Zn, Pb, Cr, Ni) during a sintering process of municipal solid waste incinerator (MSWI) fly ash. The proportions of the three constituents were varied to adjust the mixture compositions. The washing time were 8 h, 16 h and 24 h. The material was compacted in cylindrical specimens at 3 kN and treated at 1,100 degrees C for 4 h. When the clay content was increased to 70%, the stabilized ratio was increased from 16.96% to 28.42% for Cd, from 10.58% to 37.02% for Pb, from 46.38% to 55.14% for Cu, from 42.14% to 64.47% for Zn, but the stabilized ratio of Ni and Cr was decreased. When coal fly ash was increased in the MSWI fly ash, the stabilized ratio was decreased from 16.96% to 4.67% for Cd, increased from 46.86% to 81.43% for Cu, but the addition of coal fly ash did not increased the stabilized ratio of Zn, Pb, Ni and Cr. Washing pre-treatment increased the stabilized ratio of Cd, Cu and Pb significantly. The leaching behavior of the heavy metals in the sintered products was studied by the toxicity characteristic leaching procedure (TCLP), the results showed that the leaching concentration of the six heavy metals were very low.

A laboratory procedure is described for measuring methane potentials of source-separated bio-organic municipal waste (BMW). Triplicate reactors with about 20 grams fresh material were incubated at 37 degrees C with 300 mL inoculum from Shenyang wastewater treatment plant and the methane production was followed over a 50 d period by regular measurement of methane on a gas chromatograph. At 37 degrees C, the methane production efficiency of source-separated BMW and individual waste materials was: starch > BMW > protein > food oil > fat > paper. For the source-separated BMW,starch,protein,food oil,fat and paper, the methane potential (CH4/VS) of 218.15, 209.11, 194.20, 238.86, 257.82 and 131.41 mL/g were found,and ultimate biodegradability of 6 difference materials were 67.73%, 72.88%, 65.84%, 78.38%, 74.11% and 47.98%, respectively.

Composing treatments of source separation (SS) household bio-organic waste and straw mixed in 10:1, 16 kinds of PAHs in source separation household bio-organic waste and compost production were determined by gas chromatograph/mass spectrograph (GC-MS) according to U.S.EPA 8270 standard method. Comparing 16 kinds of PAHs content, distributing and biodegradability,we evaluated the PAHs risk in farmland and discoursed the impact factors of PAHs biodegradability in household bio-organic waste composting. The results show that SigmaPAH16 contents in source separation household bio-organic waste and composting production is 2.19 and 1.96 mg/kg DM, and the contents of naphthalene, fluorene, phenanthrene, fluoranthene are relatively higher than others. The percent of these four organic pollutions is 79.76% and 81.76% in PAH16, respectively. The benzene loop number of these four organic pollutions is 2-3, and it' s easily degradable non-carcinogen in farmland utilization. SigmaPAH16 biodegradability is 25.88%, and the content of PAHs in SS household bio-organic waste compost production fits the farmland utilization criteria.

The characteristics of heavy metals (Cd, Pb, Zn, Cu, Cr and Ni) were studied during pilot melting process of waste incineration fly ash, and it mainly focused on the solidification of those heavy metals in molten slag. The experiment factors include temperature (1290 degrees C, 1320 degrees C and 1360 degrees C), additive (10% glass powder), slag cooling mode(water or air cooling), whose influence on the heavy metals' solidification in the molten slag was studied. The result shows: the solidification of the heavy metals (Pb, Zn, Cu, Cr and Ni) increase on certain degree with temperature's increasing; Adding 10% glass powder makes the solidification of heavy metals increase greatly except Zn; For Zn, Cu, Cr and Ni, the solidification using air cooling mode is higher than that using water cooling mode.

The sintering process is used to stabilize the heavy metal in fly ash from municipal solid waste incinerator (MSWI). Migration characteristics of 6 targeted heavy metals (Cd, Pb, Cu, Ni, Cr and Zn) in the sintering process of MSWI fly ash were investigated by experiments. Effect of several factors including sintering temperature, residence time, molding pressure and particle diameter on the migration of heavy metals were discussed in details. The results show that cadmium and lead are volatile metals, while nickel, copper, chromium and zinc belong to involatilizable metals. The effects of sintering temperature, residence time, molding pressure and particle diameter on the stabilizing efficiency differ from each other. The study shows that most of heavy metals are stabilized during the sintering process. The stabilizing efficiency of heavy metals was different for different elements.

Vitrification process can effectively control the leachability of heavy metals in fly ash generated from municipal solid waste incinerator (MWSI). The use of liquid ceramic (LC) additive as a heavy metal chemical stabilization agent was evaluated for MSWI fly ash. The residuals of chromium, lead and zinc in slag increase by different degree with liquid ceramic additive at 1400 degrees C, while those of cadmium and copper decreases. The migrating characteristic of nickel is hardly affected by the additive less than 10%. The volatilization of Cr and Zn occurs after 61 minute with 10% addition of LC, and the binding efficiency of Cr decreases with increasing of melting temperature. The results indicate that the binding efficiency of heavy metals was affected greatly by LC additive and showed significant differences according to type of heavy metal during melting process. The short melting time (no longer than 33 min) is useful to obtain high binding efficiency of heavy metals.

The melting process of municipal solid waste incinerator (MSWI) fly ash was investigated in order to study the influence of additives on decomposition characteristics of dioxins (polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans, PCDD/Fs). The melting treatment of MWSI fly ash was performed at a batch-melting furnace with two types of additives, CaO and liquid ceramic (LC), at different melting temperatures, melting atmospheres and treatment times. The results demonstrate that the effect of CaO on PCDD/Fs' decomposition changed with the type of atmosphere. The decomposition and removal efficiency (DRE) of dioxins increased slightly with 20% CaO in an oxidative atmosphere, while it decreased obviously in an inert atmosphere. There is an important influence by liquid ceramic on the decomposition of PCDD/Fs. The DRE of PCDD/Fs in MSWI fly ash increased from 99.997% to 100% with the addition of LC increasing from zero to 10% at 1400 degrees C. The temperature, in which the PCDD/Fs were completely decomposed, decreased from 1460 degrees C to 1100 degrees C when 10% LC was added into fly ash.

F1 progenies of a genic male sterile and early maturing indica line 6442S-7 crossed with sixteen medium or late maturing varieties, such as Minghui 63, shared the same heading date as 6442S-7 under long day and short day, suggesting that 6442S-7 has completely dominant earliness. Segregation of heading dates of the F2 and B1F1 populations indicated that the earliness of 6442S-7 is mainly controlled by two dominant major genes. Whereas, heading dates of F1 progenies of 6442S-7 crossed with other four late maturing varieties, i.e. IR68, Xianguo, 9311, and BG1639, closed to the mid-parent value under long day. In F2 populations of 6442S-7 crossed with each of the four late maturing varieties, F1 from three-way crosses between 6442S-7 and each F1 of Minghui 63 crossed with each of the four late maturing varieties, and F1 from three-way crosses between 6442S-7 and each F1 of crosses between each two of the four late maturing varieties, segregation of heading dates showed that an incompletely diminant allelic suppressor for the dominant earliness of 6442S-7 existed in the late maturing varieties, IR68, Xianguo, 9311, and BG1639. It is considered that dominant earliness genes harbored in 6442S-7 have splendid future in rice improvement.

SP-6 was synthesized by solid phase method in 95% purity on HPLC. The data obtained from amino acid analysis and fast atom bombardment were in good agreement with theoretical values. Intravenous injection of SP-6 in rabbits at the dosage of 14.3 micrograms/kg. resulted in blood pressure reduction of 4.4 kPa, i.e. 34% (P < 0.001). When the concentration of SP-6 in Tyrode solution was 5.2 x 10(-4) mg/ml the contraction of rabbit duodenum longitudinal muscle increased by 105%. (P < 0.001). When the concentration was more than 1 x 10(-3) mg/ml, the contractile effect was restrained significantly. Dropping 30 microliters of SP-6 (1 x 10(-3) mg/ml) to toad intestinum tenue mesenteriale in situ, the mesentery arterioles were expanded by 30%.