Composite tantalate of rare-earth elements

FIELD: chemistry.

SUBSTANCE: invention relates to novel chemical compounds and can be used in medicine, particularly radiology as an X-ray contrast agent during X-ray examination of various organs. The invention discloses a composite tantalate of rare-earth elements with the formula M1-xM'xTaO4, where 0.01≤x≤0.45; M and M' are elements selected from a group consisting of: yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, as a contrast agent for X-ray diagnosis. The disclosed contrast agent, which provides a high level of X-ray absorption, enables to smoothly and continuously vary the level of absorption with the same quantitative content of the agent owing to change in values of x, i.e., owing to change in the ratio of atoms the first and second elements in the crystal lattice of tantalate.

EFFECT: contrast agent broadens the possibility of reliable diagnosis of cavernous organs.

10 ex

 

The invention relates to new chemical compounds and can be used in medicine, in particular to radiology, and can be used as a Radiocontrast agent for x-ray studies of various organs.

Known means for contrast enhancement in x-rays, containing tantalum at least one element selected from the group comprising yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium or bismuth, a polysaccharide and water (patent RU 2297247, IPC AC 49/04, 2007).

However, the known means can be used only in case of diagnosis using the field of low-energy x-rays (about 35÷45 Kev).

Known contrast agent for imaging-based lanthanide phosphate, where the lanthanide selected from the group of elements including elements of the Periodic system having an atomic number from 57 to 71, and the lanthanide can be derovan with terbium (patent US 4310507, IPC AC 49/04, 1982). Known agent can be used for x-ray energy corresponding to the K-absorption jump of each individual lanthanide, phosphorus and terbium.

However, the introduction into the organism of a contrast agent on the basis of phosphates can lead to bre is the balance between phosphorus and calcium, which in turn leads to poor absorption of calcium and increased deposition of calcium and phosphorus in the kidneys and, consequently, contributes to the development of osteoporosis. In addition, phosphorus has To jump in and 2.14 Kev, which is not included in the range of x-ray radiation of modern medical equipment.

Known contrast agent on the basis of bismuth oxide having a stabilizing layer made of silicon oxide or polymeric materials (patent EP 2127682, IPC AC 49/04, 2009).

The disadvantage of the agent is its effective use is only for x-ray energy corresponding To-jump absorption of bismuth 90,5 Kev.

Known contrast agent for computed tomography in the form of nanoparticles of at least one oxide selected from the group of tungsten oxide, tantalum oxide, hafnium oxide, bismuth oxide, coated with a polymer membrane (patent EP 2121038, IPC AC 49/04, 2009). Known agent has several K-surges of energy absorption in the desired range corresponding to each of the constituent metals.

However, the known agent is a mechanical mixture of several oxides, which over time leads to the precipitation of suspended particles of oxides in the sediment, making it impossible to further use an agent. In addition, a well-known agent can be is used only at discrete intervals absorption energies of each of the metals, included in its composition. When it is impossible smooth change in x-ray absorption and, consequently, the contrast of the abdominal organs in a wide energy interval, for example, that it is necessary in radiography of the biliary tract by x-ray study, cholecystocholangiography and cholangiography.

Thus, the authors faced the task of developing a contrast agent for x-ray, which not only would provide effective absorption of x-rays in a wide energy interval, but had the possibility of continuous and smooth variation of the absorption in this range.

The problem is solved in a new chemical compound - complex tantalate rare earth element composition of M1-XM'XTaO4where is 0.01≤x≤0,45; M and M' elements selected from the group of yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium; which is used as a contrast agent for x-ray.

Currently, the patent and scientific literature is not known complex tantalate proposed composition that can be used as contrast agents in x-rays.

The authors managed to get a new chemical compound with the ability to absorb x-ray radiation widely in the energy range of the radiation, which allows you to continuously and smoothly change the absorption of energy in this interval when the same amount of agent injected into the patient. Continuous and smooth energy absorption was obtained by changing the ratio of atoms of elements in the crystal lattice tantalate, which is a solid solution of substitution. Experimentally, the authors have established the limits of the possible changes in the ratio of atoms of elements. When values of x less than 0.01 solid solution is formed, but the level of energy absorption remains almost the same as in the case of using tantalate single item. When the values x more than 0.45 observed the formation of a mechanical mixture of tantalates two rare earth elements, which does not allow smooth changes in x-ray absorption. In addition, leads to sequential precipitation of suspended particles tantalate in the sediment (first with higher molar mass).

The proposed new chemical compound can be obtained in the following way. Take two powders tantalate elements selected from the group of yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, are thoroughly mixed in a ratio tantalate M:tantalate M'=1-x/x, where x is the mole fraction tantalate M', of 0.01≤x≤0,45; placed in n the e and calcined in air at a temperature of 1350-1550°C for 30-50 hours. The homogeneity of the obtained product check x ray powder diffraction method (XRD). Get complex tantalum rare earth elements of the General formula M1-XM'XTaO4where is 0.01≤x≤0,45; M and M' elements selected from the group of yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium. The absorption of x-rays received tantalate measured in vitro relative to water and known radiopaque means "Urographine". To measure the powder tantalate add in one of the natural polymers, such as carboxymethylcellulose. The obtained gel-like suspension is poured into glass bottles, registered x-ray image of the bottles on x-ray film. Then take the tape and measure the density of blackening the image of the bottles with the suspension relative to the images of the bottles with water or "Urografin".

The proposed solution is illustrated by the following examples.

Example 1. Take 7,6853 g tantalate of yttrium YTaO4and 2,3147 g of gadolinium tantalate GdTaO4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in a furnace at a temperature of 1350°C for 50 hours in an atmosphere of air. Then the oven is off and cool arbitrarily to room temperature. According to the XRD get complicated tantalate composition Y0,8Gd0, TaO4with unit cell parameters (Å) a=5,3662; b=5,5717; C=5,1424. The composition has To races absorption (Kev): Y - 17,038; Gd - 50,233; TA - 67,4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to water by x-ray analysis. 100 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densitometer. The reference point we take the degree of absorption of water. Get S=124,0 oted

Example 2. Take 8,2468 g tantalate of yttrium YTaO4and 1,7532 g of gadolinium tantalate GdTaO4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in a furnace at a temperature of 1550°C for 30 hours in air. Then the oven is off and cool arbitrarily to room temperature. According to the XRD get complicated tantalate composition Yof 0.85Gdof 0.15TaO4with unit cell parameters (Å) a=5,3351; b=5,5473; C=5,0925. The composition has To races absorption (Kev): Y - 17,038; Gd - 50,233; TA - 67,4 (all races are in the range of 10-150 Kev used in x-rays). Absorption Ren is gannovskogo radiation measured in vitro relative to water by x-ray analysis. 100 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densimeter. The reference point we take the degree of absorption of water. Get S=126,0 oted

Table 1 shows the data of x-ray absorption complex tantalate yttrium and gadolinium when changing the values of x in the claimed range of values. The data indicate a continuous and smooth change in x-ray absorption by tantalate at the same content in the suspension.

Table 1
CompositionThe value of xThe density of blackening, oted
Gdfor 0.6Yfor 0.4TaO40,4124,0
Gd0,7Yfor 0.3TaO40,3126,1
Y0,8Gdof 0.2TaO40,2124,0
Yof 0.85Gdof 0.15TaO40,15126,0
Y0,86Gd0,14TaO40,14126,5
Y0,875Gd0,125TaO40,125125,0
Yfor 0.9Gda 0.1TaO40,1125,0

Example 3. Take 4.0 g of yttrium tantalate YTaO4and 5,91 g tantalate dysprosium DyTaO4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in a furnace at a temperature of 1550°C for 30 hours in air. Then the oven is off and cool arbitrarily to room temperature. According to the XRD get complicated tantalate composition Dy0,55Y0,45TaO4with unit cell parameters (Å) a=5,32; b=5,460; C=5,088. The composition has To races absorption (Kev): Y - 17,038; Dy - 53,793; TA - 67,4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to the radiopaque means "Urographine by x-ray analysis. 100 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into the glass vial is irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densimeter. The reference point we take the degree of absorption means "Urographine". Get S=65,0 oted

Example 4. Take 0.1 g of yttrium tantalate YTaO4and 11,96 g tantalate dysprosium DyTaO4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in a furnace at a temperature of 1450°C for 35 hours in an atmosphere of air. Then the oven is off and cool arbitrarily to room temperature. According to the XRD get complicated tantalate composition Dy0,99Y0,01TaO4with unit cell parameters (Å) a=5,35; b=5,455; C=5,046. The composition has To races absorption (Kev): Y - 17,038; Dy - 53,793; TA - 67,4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to the radiopaque means "Urographine by x-ray analysis. 100 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densimeter. The reference point we take the degree of absorption means "Urographine". Get S=45,0 Rel. units

Example 5. B is Ruth 0,8815 g tantalate of yttrium YTaO 4and 0,1185 g tantalate terbium bO4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in air at a temperature of 1450°C for 45 hours. Then the heating is switched off and the oven cooled arbitrarily to room temperature. According to the XRD of the sample receive complex tantalate composition Y0.9Tba 0.1TaO4with unit cell parameters (Å) a=5,33, b=of 5.53,=5,10. The composition has To races absorption (Kev): Y - 17.038, Tb - 52.002, TA - 67.4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to water by x-ray analysis. 5 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densitometer. For reference take the value S of water. Get S=127,0 Rel. units

Example 6. Take 0,8800 g tantalate of yttrium YTaO4and 0,1200 g tantalate holmium, Noto4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in air at a temperature of 1450°C for 45 hours. Then the heating is switched off and the oven cooled PR is isolino to room temperature. According to the XRD of the sample receive complex tantalate composition Y0.9Hoa 0.1TaO4with unit cell parameters (Å) a=5,32, b=5,52, c=of 5.05. The composition has To races absorption (Kev): Y - 17.038, But 55.619, TA - 67.4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to water by x-ray analysis. 5 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densitometer. For reference take the value S of water. Get S=USD 128.0 Rel. units

Example 7. Take 0,8794 g tantalate of yttrium YTaO4and 0,1206 g tantalate erbium, EGTA4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in air at a temperature of 1450°C for 45 hours. Then the heating is switched off and the oven cooled arbitrarily to room temperature. According to the XRD of the sample receive complex tantalate composition Y0.9Era 0.1TaO4with unit cell parameters (Å) a=5,31, b=5,51, c=5,03. The composition has To races absorption (Kev): Y - 17.038, It is 57.487, TA - 67.4 (all races lie in the interval for the e 10-150 Kev, used in x-rays). The absorption of x-ray radiation measured in vitro relative to water by x-ray analysis. 5 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densitometer. For reference take the value S of water. Get S=126,0 Rel. units

Example 8. Take 0,8789 g tantalate of yttrium YTaO4and 0,1211 g tantalate thulium, TMTA4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in air at a temperature of 1450°C for 45 hours. Then the heating is switched off and the oven cooled arbitrarily to room temperature. According to the XRD of the sample receive complex tantalate composition Y0.9Tma 0.1TaO4with unit cell parameters (Å) a=5,30, b=5,50, c=5,01. The composition has To races absorption (Kev): Y - 17.038, Tm - 59.38, TA - 67.4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to water by x-ray analysis. 5 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass the vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densitometer. For reference take the value S of water. Get S=USD 128.0 Rel. units

Example 9. Take 0,8779 g tantalate of yttrium YTaO4and 0,1221 g of ytterbium tantalate YbTaO4thoroughly mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in air at a temperature of 1450°C for 45 hours. Then the heating is switched off and the oven cooled arbitrarily to room temperature. According to the XRD of the sample receive complex tantalate composition Y0.9Yba 0.1TaO4with unit cell parameters (Å) a=from 5.29, b=5,49,=5,00. The composition has To races absorption (Kev): Y - 17.038, Yb - at 61.30, TA - 67.4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to water by x-ray analysis. 5 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densitometer. For reference take the value S of water. Get S=129,0 Rel. units

Example 10. Take 0,8774 g tantalate of yttrium YTaO4and 0,1226 g of lutetium tantalate LuTaO4, carefully the nutrient mix in Jasper mortar. The mixture is placed in alongby the crucible and calcined in air at a temperature of 1450°C for 45 hours. Then the heating is switched off and the oven cooled arbitrarily to room temperature. According to the XRD of the sample receive complex tantalate composition Y0.9Lua 0.1TaO4with unit cell parameters (Å) a=5,28, b=5,48,=5,00. The composition has To races absorption (Kev): Y - 17.038, Lu - 63.31, TA - 67.4 (all races are in the range of 10-150 Kev used in x-rays). The absorption of x-ray radiation measured in vitro relative to water by x-ray analysis. 5 ml of 10%suspension obtained tantalate in the carboxymethyl cellulose is poured into a glass vial and irradiated with renthendorf ROOM-20M (tube with copper anti-cathode) at a voltage of 57 kV and current of 40 mA using film Retina. Then take the tape and determine the density of blackening (S) densitometer. For reference take the value S of water. Get S=130,0 Rel. units

Thus, the authors propose a new chemical compound - complex tantalum rare earth element composition of M1-XM'XTaO4where is 0.01≤x≤0,45; M and M' elements selected from the group of yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium; which can be used as a contrast agent in roentgenodiagnostic is. Moreover, the contrast agent, providing a high level of absorption of x-rays, allows you to smoothly and continuously change the level of absorption at the same quantitative content of the agent by changing the values of x, that is, by changing the ratio of atoms of the first and second elements in the crystal lattice tantalate. We offer a contrast agent extends the reliable diagnosis of abdominal organs.

Complex tantalum rare earth elements
M1-xM'xTaO4,
where is 0.01≤x≤0,45; M and M' elements selected from the group of yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, as a contrast agent for x-ray.



 

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1 ex,1 tbl

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4 cl, 3 dwg, 7 ex

FIELD: chemistry.

SUBSTANCE: invention refers to the preparation of the materials for ferroelectric ceramics used in electronics. The method includes the hydrolysis of rare metal compound with formation of rare metal precipitate which is then separated and suspended. The compound of the alkali or bivalent metal is fed into suspension at pH 5.5-13 and temperature 71-95°C. The suspension is vigorously mixed during 15 min or more at the value of Reynolds criterion (8-20)·104. The ferroelectric powder is washed and dried at the temperature 40-95°C. The rare metal compounds are compounds of titanium, zirconium, tantalum or niobium in the form of fluorides, chlorides, sulphates or phosphates. The alkali metals compounds are used in the form of hydroxides, chlorides, nitrates or sulphates. The bivalent metals compounds are compounds of barium or strontium in the form of hydroxides, nitrate, chlorides, sulphates as well as lead nitrate.

EFFECT: providing of the particle size control of the nanodimensional powders of the titanates, zirconates, tantalates or niobates of mono- and bivalent metals and obtaining of stoichiometric powders with narrow grading and saving of monophasity

8 cl, 10 ex

FIELD: chemical industry; electronic industry; other industries; methods of production of tantalum hydroxide.

SUBSTANCE: the invention is pertaining to the synthesis of the inorganic compounds, in particular, to the method of production of tantalum hydroxide and may be used for manufacture of the materials used in the computer, electronic and optoelectronic equipment. The method of production of tantalum hydroxide provides for treatment of the tantalum pentachloride with the ammonia solution, decantation of the solution, filtration and drying of the sediment. The treatment of the tantalum pentachloride is conducted using the ammonia solution with concentration of 6.0-9.5 mole/l at the ratio of the volumes of the solid and liquid phases of 1:(3-5). The technical result of the invention is simplification of the process of production of tantalum hydroxide with the increased content of the tantalum pentaoxide, the low content of the chloride-ion and the increased specific surface of the produced hydroxide.

EFFECT: the invention ensures simplification of the process of production of tantalum hydroxide with the increased content of the tantalum pentaoxide, the low content of the chloride-ion and the increased specific surface of the produced hydroxide.

8 ex, 1 tbl

FIELD: production of europium hepta tantalate of class of complex rare-earth elements for manufacture of quantum electronics materials.

SUBSTANCE: proposed method includes mixing tantalum compounds with aqueous solution of europium salt followed by heat treatment of suspension thus obtained. Used as tantalum compound is tantalum hydroxide and europium acetate solution is used as aqueous solution of europium salt at europium concentration of 0.58-0.060 mole/l; heat treatment of product is carried out at temperature of 850-900C for 4-5 h.

EFFECT: reduction of synthesis temperature and duration of process.

1 tbl, 1 ex

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention relates to a novel tantalum pentachloride preparation method, which can be used to recover tantalum in the form of its pentachloride from tantalum-containing stock. Method comprises interaction of tantalum pentoxide with silicon tetrachloride at elevated pressure and temperature. Process is effected in autoclave under autogenous pressure developed when heating solid mixed concentrate to 245-300°C.

EFFECT: avoided formation of high-toxicity compounds such as phosgene, carbon monoxide, and chlorinated hydrocarbons.

1 tbl

FIELD: production of alkaline metametals (V) used for production of laser, electric optical, ferroelectric materials and special-purpose ceramics.

SUBSTANCE: stoichiometric amount of niobium and/or tantalum oxyhydroxide and lithium nitrate and/or sodium nitrate is subjected to ultrasound treatment in inert organic fluid, mainly white spirit for obtaining mixture of components at size of particles lesser than 1 mcm. In the course of heating this mixture at temperature of 300-350°C, lithium and/or sodium nitrates are decomposed forming respective nitrites. At temperature of 400-450°C, lithium and/or sodium nitrites are decomposed forming respective oxides. At calcination of mixture at temperature of 580-700°C continued for 1-0.5 h, oxides of alkaline metals interact with amorphous niobium and/or tantalum oxyhydroxides forming respective alkaline metametals (V) or solid solutions, type LixNa1-xNbyTa1-yO3. Proposed method is used for production of mono-phase metaniobate or metatantalate of lithium or sodium and solid solutions of stoichiometric composition at low temperature of calcination.

EFFECT: enhanced efficiency; increased yield of product.

5 cl, 6 ex

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention relates to the area of hydrochemical fluoride processing of tantalum stock into pure tantalum an niobium compounds. Potassium fluorotantalate is heated to 220-250°C 1-3 times with intermediate coolings to 70-80°C to achieve 85% of product with fineness -100+40 μm. Product is then subjected to ammonia treatment at ambient temperature followed by hydrochloric acid treatment. Ammonia and hydrochloric acid treatments are performed 2-4 times each.

EFFECT: achieved full decomposition of potassium fluorotantalate to form granulated precipitate, increased purity of tantalum pentoxide, moderated purity requirements for starting material and reagents, and reduced corrosion of equipment.

1 dwg, 1 tbl

FIELD: inorganic synthesis.

SUBSTANCE: invention relates to preparation of niobium and/or tantalum pentachlorides from niobium and/or tantalum oxides and/or oxychlorides and comprises reaction of oxide or oxychloride compounds with chlorination agent, namely double aluminum chloride-phosphorus pentachloride compound AlCl3·PCl5. Process is carried out at 100 to 400° C. Exhausted chlorination agent is then regenerated by chlorinating it in presence of sulfur at 500-600° C or in presence of carbon at 800-900° C. After chlorination of oxide or oxychloride compounds with AlCl3·PCl5 chlorination is continued using AlCl3·POCl5. In another embodiment of invention, chlorination is accomplished using, as chlorination agent, melts based on formulations similar to eutectics formed by AlCl3·PCl5 or AlCl3·POCl5 and sodium and/or potassium chloroaluminates or chloroferrates. Resulting niobium and/or tantalum pentachlorides are recovered from reaction mixture via rectification.

EFFECT: achieved environmental safety of reactants and reaction products and fullness of chlorination, lowered temperature, accelerated process, and reduced expenses.

6 cl, 5 ex

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to oncology and surgery, and can be used in treating malignant gastric and duodenal tumours. That is ensured by diagnostic angiography, detecting arteries mainly feeding gastric and duodenal tumour zones. Then a chemopreparation in Lipiodol 0.5-1.0 ml is introduced in a gastroduodenal and/or left or right gastric and/or gastroomental arteries with using no more than 1/3 of a single dose. The treatment is carried out not at least 1 time a month.

EFFECT: method allows providing effective regional chemotherapy with a minimum toxic effect on the patients suffering said pathology with simultaneous decrease in chemopreparation and Lipiodol dose decline.

3 cl, 2 ex

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