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Biomedical subjects

Iu V Kudriavtsev

Publications and source records attributed to Iu V Kudriavtsev.

At least 19 recordsLinked to original sources
PubMed2006

[The morphologic and functional state of the kidneys exposed to focused waves during remote nephro-lithotripsy].

Clinical and experimental research has shown that complications connected with negative influence of focused waves in distant lithotripsy in litotripters with an electrohydravlic system of focused waves generation depend on many factors, including the regime of wave generator work, an electrode interval, defocusing the wave as a result of an electrode interval center displacement, the amplitude of pressure and the length of a wave impulse in positive and negative phases. The wave impulse is distorted, which leads to kidney tissue damage.

Adult↗
PubMed2002

[Morphofunctional characteristics of erythrocytes in chronic kidney failure and purulent intoxication].

The morphology of blood erythrocytes was examined under a scanning electron microscope and erythrocyte surface charge, lipid peroxidation on erythrocyte membranes, and blood viscosity were studied in 213 urological patients with chronic renal insufficiency (CRI) and purulent intoxication (PI) of different severity. CRI and PI were characterized by morphofunctional changes in erythrocytes, which depended on the type and severity of intoxication. Changes in erythrocyte morphology in CRI and PI were paralleled by a decrease in their negative surface charge and activation of lipid peroxidation. These parameters can serve as diagnostic tests for evaluation of the severity of intoxication.

Adolescent↗
PubMed2002

[Morphofunctional characteristics of erythrocytes in extracorporeal efferent detoxication].

The erythrocyte morphology (scanning electronic microscope, the superficial erythrocyte charge, the lipid peroxidation rate and the blood viscosity were investigated in 78 patients, treated by use of hemodyalisis, hemosorbtion, plasmosorbtion and hyperbaric oxygenation to correct the chronic renal insufficiency and the purulent intoxication. The described erythrocyte changes reflect the features of definite kind of the efferent treatment and the program of its use, the individuality of the patient initial state. The efferent methods of treatment cause significant and mostly differently directed changes in the peripheral red blood. Morphologic and functional parameters of the erythrocytes appear to be important diagnostic criteria of the efficiency of the extracorporal methods of detoxication.

Electricity↗
PubMed1998

[The evaluation of the effect of permanent magnetic waves with geomagnetic strength on the severity of endotoxicosis].

The motor restraint stress in rats was treated with permanent magnetic fields of the geomagnetic strength generated by authors' apparatus GEOMAG. The GEOMAG therapy appeared to expedite reduction in blood levels of mid-molecular toxic products in stressed animals. Determination of the Ca-ATPase activity showed that 3 to 6 hours of treatment significantly (up to 34% and 29%, respectively) decreased the inhibiting activity of plasma. This decrease was particularly marked after the geomagnetic field therapy. These results give evidence that the GEOMAG-produced geomagnetic fields favor more rapid detoxication of stressed organism through more effective neutralization of metabolites in the spleen and renal excretion. Hence, the method shows promise with regard to the postflight rehabilitation of flying personnel.

Animals↗
PubMed1993

[The effect of upper urinary tract interior drainage on urodynamics and contractile function of the ureteral wall].

S-stents were introduced to the upper urinary tracts of experimental dogs on a period from 1 week to 11 months. It was found mild ureter dilation, the increased ureter pressure, refluxes along the upper urinary tract, the lowered flow resistance during perfusion and diuretic loads. Isolated ureter wall fragments demonstrated the diminished contractility in vitro, and the mode of their contractile force adrenergic regulation was modified. The reduced ureter pressure during large flows after indwelling S-stents to the ureters may be the factor that facilitated the renal and ureter stones removing but the decreased contractility and ureter refluxes emphasized that the period of stent implantation to the upper urinary tracts must be pathogenetically and clinically evident.

Animals↗
PubMed1992

[The use of cryopreserved arteries as arterial vascular prostheses].

The aim of the study is investigation of possibility to bypass small and medium-size arteries with cryopreserved artery allografts, storing 7-10 days at -196 degrees C under the protection of 15% dimethylsulfoxide. In experiments on 40 rabbits were placed a region of the left renal artery by cryopreserved bioprosthesis. Graft patency was 80% after observation up to 6 months. By angiography it was 8 cases of graft thrombosis (all during the 1st week after implantation) and 5 cases of moderate graft dilation (in 4 of them it was accompanied with stenosis of distal anastomosis). In 20 dogs we replaced a region of the femoral artery by cryostoring bioprosthesis. It was only one case of graft thrombosis which occurred on month 2 after the implantation during 1-year follow-up. After 3 months in 3 cases there developed 3 cases of diffuse narrowing of graft lumen without decreasing of blood flow through the prosthesis. Later, the graft lumen did not change. Histological investigations have revealed a viability of cryopreserved vessels, its almost complete de-endothelialization at 3 days and total re-endothelialization 2 weeks after implantation. During the first 2 weeks there were morphological events of graft rejection, which disappeared after 3 months.

Animals↗
PubMed1992

[The prospects for the use of a Soviet apparatus for the removal of gallstones with focused shock waves].

Clinico-experimental substantiation was conducted for extracorporal crushing of the stones in biliary ducts in patients who suffered from gallstone disease. The "Urat-II" national lithotriptor and "Urat-B" biostand were used to crush in experimental conditions 140 gallstones (0.5-2.5 cm in size) obtained during cholecystectomies. Experimental researches on 56 white rats were conducted to study the liver tissue and adjacent organs. Optimal regimes for the percussive wave generator were found out in which the best crushing effect was obtained (with the dimensions of fractions up to 1.6 mm) and at the same time the minimal disturbing factor was produced. The data obtained during these researches are used in clinical pilot testings on "Urat-II"--a prototype of the national cholelithotriptor.

Adult↗
PubMed1991

[Experimental megaureter in dogs: modeling by "devitalization" of a segment of the ureter and features of the course].

The method of experimental megaureter modelling in dogs that is based on the operative damage of the ureter segment is described. Obstructive megaureter was found in 100% of "devitalization" of the ureterovesical junction and in 59% of "devitalization" of the middle third of ureter. Progression of megaureter symptoms and reduction of evacuator-secretory function on the side of modelling operation without anatomical narrowing of the ureter lumen in 41% of experiments pointed to the actual role of the functional obstruction in pathogenesis of this hard syndrome. In vitro methods demonstrated the decrease of contractility of the "devitalized" fragments and also of above and below situated segments of megaureter. Urodynamic investigations showed the signs of the bioelectrical disturbance in the megaureter wall and the disorder in excitement and contraction of the megaureter, deterioration of the reactivity of the megaureter on the functional loading tests.

Animals↗
PubMed1980

[Histocytospectrophotometric characteristics of lung cancer].

The paper presents the results of quantitative changes in the activity of some most important oxidative-reductive enzymes in lung carcinoma cells. The histo- and cytospectrophotometric studies were carried out on the operation material removed from 32 patient with lung carcinoma including 12 cases of squamous cell carcinoma, 12 cases of adenocarcinoma, 4 cases of undifferentiated large cell and 4 cases of undifferentiated small cell carcinoma. Statistically significant increases in the activity of G-6-PDH, NADP-D and LDH were observed in a decreasing degree of tumour differentiation with a simultaneous relative decrease in the activity of SDH, MDH NAD-D and alpha-GPDH. When the activity of oxidoreductases was compared in tumours having the structure of squamous cell carcinoma and adenocarcinoma, a higher activity of LDH, SDH and alpha-GPDH in squamous cell carcinoma and high activity of G-6-PDH and NADP-D in adenocarcinoma were observed. Statistically significant differences in the activity of carbohydrate metabolism enzymes in small cell carcinoma and other histological forms of lung cancer were found: a significant increase in G-6-PDH and LDH and relative decline in the activity of SDH and alpha-GPDH. In all the examined histological forms of lung cancer there was a complete agreement in the results of histo- and cytospectrophotometric examinations of the activity of the main oxidative-reductive enzymes.

Adenocarcinoma↗
PubMedDate not supplied

[Effects of focused shock waves on children's kidney: experimental study].

The effects of focused shock waves produced by URAT-P2 unit on renal tissue was studied in 120 immature rats with 100-120 g b.w. Morphological material obtained after the procedure and 3 months after it was studied with reference to the following parameters of the impact: interelectrode spacing, capacitor capacitance, capacitor charging voltage, pressure in the therapeutic focus, number of impulses. It was found that one of the essential damaging factors of the shock waves is spontaneous widening of the interelectrode spacing in the course of the fragmentation which entails an increase in the pressure amplitude in the center of the therapeutic focus with resultant prolongation of the impulse.

Aging↗
PubMedDate not supplied

[Surgical treatment of urinary bladder cancer].

Ultrasonic transabdominal and transrectal investigations, computed tomography, endoscopic photodynamic studies, polyfocal biopsy of the urinary bladder were used in examination of 1238 patients which were diagnosed to have urinary bladder cancer. 894 patients underwent transurethral resection of the bladder. Morphologically, cancer of the urinary bladder has an inductory effect on intact parts of the bladder mucosa. This means that even most radical resection does not eliminate grounds for a new tumor growth. Radical cystectomy was performed in diffuse papillomatosis, multiple stage T2 tumors of high-grade malignancy, tumors at stage T3, T4, Nx, MO, in rapid recurrent tumors after conservative or operative treatment.

Cystectomy↗
PubMedDate not supplied

[Results of upper urinary tract malformations correction in adults operated in childhood].

3-13-year follow-up results are presented for 83 adult patients operated in childhood for ureterohydronephrosis, hydronephrosis, vesicoureteral reflux. Positive results were obtained in adults operated in early childhood when renal and urinary compensatory mechanisms were stronger. In hydronephrosis and vesicoureteral reflux the results were better than in ureterohydronephrosis. Combined clinical, morphological and experimental investigations have revealed a direct relationship between renal, ureteral functional reserves in adult patients and age of the correcting operation in childhood, degree of intactness of the kidneys and urodynamics, regenerative ability of leiomyocytes.

Adolescent↗
PubMedDate not supplied

[Treatment of solitary renal cysts in children].

The authors formulate therapeutic policy basing on clinical, ultrasound and parenchymal morphological studies in 34 children with solitary renal cysts. Operative intervention is indicated in renal function decline manifesting with enlargement of the cyst and reduction of the cystic-renal coefficient. The kind of the operation is decided by location of the cyst and its characteristics obtained at radiodiagnosis. In slow growth of the cyst and no further decline in its function the patients should be followed up as a risk group.

Adolescent↗
PubMedDate not supplied

[Fluorescent diagnostics of urinary bladder cancer].

Introduction of optic markers in screening for cancer of the urinary bladder (UB) raises diagnostic significance of UB cystoscopy. Application of intravesical form of 5-aminolevulinic acid (5-ALA), precursor of photodynamically active protoporphirine IX, prevents complications in systemic use of tetracycline or hepatoprophirines. Fluorescent cystoscopy with 5-ALA (n = 59) was made in 51 patients treated in the Research Institute of Urology. UB cancer was detected in 32 patients. This procedure proved highly sensitive and specific (97.0 and 75.6%, respectively, being much more effective than standard cystoscopy and biopsy in the white light (85.1 and 81.4%, respectively). Specificity of fluorescent cystoscopy is much higher in detection of tumors and pretumor lesions (88.4%). Fluorescent diagnosis is expected to become a gold standard in the program of UB cancer detection.

Administration, Intravesical↗