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Biomedical subjects

I Iordanov

Publications and source records attributed to I Iordanov.

At least 19 recordsLinked to original sources
PubMed2006

Anion photoelectron spectroscopy and density functional investigation of vanadium carbide clusters.

The influence of source conditions on vanadium-carbon cluster formation in a methane-vanadium plasma is explored and analyzed by photoelectron spectroscopy, revealing that the metal-carbon ratio has substantial influence over the cluster products. Experiments that employ large methane content produce carbon-rich mono- and divanadium carbides. The carbon-rich clusters show a preference for the formation of cyclic neutral and linear ionic structures. When the methane concentration is decreased, VmCn clusters are formed with m = 1-4 and n = 2-8. The photoelectron spectra of clusters formed under these conditions are indicative of a three-dimensional network. We have measured a significantly lower vertical electron affinity for the VC2, V2C3, and V4C6 clusters compared with proximate species. Interestingly, the VC2 species is a proposed building block of the M8C12 Met-Car cluster, and the 2,3 and 4,6 clusters correspond to the 1/4 and 1/2 Met-Car cages, respectively. This correlation is taken as evidence of their importance in the formation of the larger Met-Car species. These results are supported by density functional theory (DFT) calculations carried out at the PBE/GGA level.

Journal Article↗
PubMed1999

[Grading intraductal breast carcinoma].

Mammographic screening has led to increased detection of intraductal carcinoma of the breast (IdC). IdC is y heterogeneous disorder with different clinical outcomes. The study was designed to confirm consensibility of the three-tiered classification, accepted by Thomas Jefferson University Consensus Conference since 1997. The study population comprised 30 patients with IdC including patients with T1 mic and T1a. Sixty percent of IdC were classified as II-nd grade, 27% were III-rd grade and 13% as I-st grade. 20% of IdC exhibited heterogenity of grade. The cases with cribriform and papillary architecture were 1-st or II-nd grades. The other cases with comedo and solid architecture we are II-nd or III-rd grades. The cases with invasive component (T1 mic u T1a) were 25%--I-st grade, 75%--II-nd grade and III-rd grade--87.5%. In conclusion, the grading of IdC could y prognostic factor in far long term prognosis of patients with those lesions.

Breast Neoplasms↗
PubMed1990

[Right-sided congenital diaphragmatic hernia in infants--a report of 5 cases].

1343 dead children, aged 0-14 years, with undergone autopsies at the chair of pathological anatomy of the Higher Medical Institute in the town of Pleven were studied for a 12-year period (1978-1989). There were 29 cases with congenital diaphragmatic hernia (CDH)--2.16%. 5 out of 19 children had right side CDH--0.37%. The ratio right side/total number of CDH was 1:5.8. This ratio is between 1: to 1:8 according to literary data. The observed cases were: male sex--2, female sex--3; stillborn--1, preterm of 1 degree--3. The shortest survival was 2 hours and 20 minutes, the latest manifested CDH was after 2 hours and months and 15 days. The observed cases were described in details in respect to localization and size of defects, hernial content, clinical course, pathologicoanatomic examination and causes of lethal outcome. The decisive role of roentgenological examination in timely establishment of diagnosis is stressed.

Bulgaria↗
PubMed1990

[A hygienic study of new raw materials for cosmetic agents and household chemical preparations].

Studies are performed on the new Bulgarian raw materials "Aminookis" (AO) and "Dezodorirashch agent" (DA) the plants "Alen Mak"--Plovdiv and "Hyaluron"--Sofia. Chemical, toxicological and microbiological studies are carried out. Thin-layer chromatographic and spectrophotometric methods for determination of AO, hyaluronic acid and DA are developed and chemical studies on cosmetics, prepared with them, are carried out. During the repetition of a 21-day experiment on guinea pigs the threshold irritative concentrations--10% for AO and DA (as trade products) are determined. This shows that they are moderate contact irritants. The hyaluron has no irritative effect. By maximizing test with guinea pigs is established the absence of contact allergy for DA and AO. At index of sensibilization 10% the hyaluron falls in the group of weak allergens. The spectra of action are studied and the minimum suppressing concentrations of AO and DA are defined. It is established that the most resistant to effect with these cosmetics are the representatives of the families: Pseudomonas, Klebsiella, Escherichia, Salmonella. Recommendations are made to use "Aminookis" (AO) in shampoos to 8%, deodorizing agent in deodorants to 2% and "Hyaluron" in creams to 20% (as trade products).

Animals↗
PubMed1990

[Atypical anatomical variants and anomalies of the biliary tract in patients with biliary tract and pancreatic diseases. I. The incidence according to ERCP].

Of 570 patients with clinical manifestations of bile duct and pancreas diseases, examined by ERCP, 122 had different atypical anatomical variants (142 in 114 patients) and anomalies of the biliary passages (8 patients). The incidence of the individual atypical anatomical variants of the bile ducts was, as follows: 1. variants in the entry of the common bile duct in the duodenum--3.3 per cent (19 of 570 patients); 2. variants in the entry of ductus cysticus in the common bile duct--11.1 per cent (63 of 570 patients); 3. variants of the ramifications of the hepatic canals--10.5 per cent (60 of 570 patients). Of the bile duct anomalies, choledochocele was the most common--in 5 of the 8 patients in this group. In addition, there was a double gall bladder, gall bladder atresia and cysts of the intrahepatic bile ducts in one case each. High was the incidence of choledocholithiasis (63 per cent) and especially of primarily formed calculi in the common bile duct (20 per cent), as well as bile duct cancer (11 per cent). Cancer of the biliary passages was significantly commoner in atypical anatomical variants of ductus hepaticus (18 per cent) vs. 8 per cent in atypical variants of ductus cysticus and none in the common bile duct variants (chi 2 = 4.06; p less than 0.05). Cancer of the common bile duct was found also in 1 of the eight patients with anomalies of the biliary passages.

Age Factors↗
PubMed1990

[The relationship between duodenal diverticula, biliary tract and pancreatic diseases and their endoscopic treatment].

Of 570 ERHP performed in patients with biliary tract and pancreas diseases, duodenal diverticuli were found in 67 (11.8 per cent). Diverticuli were more frequently diagnosed in patients beyond 60 years of age (67.2 per cent). In 83.6 per cent the diverticuli were single, mostly measuring 15-30 mm and localized in the peripapillary area (70 per cent). ERHP was successful in 85 per cent. Diverticuli were most frequently accompanied by stenosing papillo-odditis (82 per cent), cholecystitis (67 per cent), common bile duct calculosis (58 per cent), followed by pancreatitis (37 per cent) and cancer of the bile ducts (4.5 per cent). Endoscopic treatment was conducted in 46 cases: endoscopic sphincterotomy, hydrostatic balloon dilation of narrowed segments, hydrostatic balloon extraction of calculi, mechanical lithotripsy, nasolabial drainage and endoprosthesis. Significantly lower was the technical success of endoscopic sphincterotomy (78 per cent) when compared with its performance in patients without diverticuli (99 per cent). In spite of this, complex endoscopic treatment resulted in significant fall of bilirubin level (t = 6.58; p less than 0.0001), of AP (t = 8.15; p less than 0.001), of GGJP (t = 6.99; p less than 0.0001), of AcAT (t = 7.14; p less than 0.01). The incidence of complications (6.5 per cent) was not higher than the one observed in patients without diverticuli. In conclusion, endoscopic treatment of bile duct diseases is recommended to be performed also in patients with diverticuli, especially in adult patients and in those exposed to increased operative risk.

Aged↗
PubMed1989

[Endoscopic treatment of cholangitis via an external nasobiliary drain].

The acute suppurative cholangitis is an acute emergency condition requiring quick decompression of the obstructed bile pathways. The authors present their experience in the treatment of 51 patients by endoscopic sphincterotomy with or without mechanical lithotripsy and extraction of the stones and a nasobiliary drainage for 5 up to 15 days. Technically the manipulation was 100% successful and its therapeutic efficacy was 94.2% including II patients to whom it was performed as a preoperative procedure. In 6 patients (11.8%) a transitory amylase elevation was registered and one patient (2%) developed acute pancreatitis. The treatment was unsuccessful in 6% of the patients--these were patients with severe liver impairment (biliary cirrhosis) and long term cholangitis. The authors recommend the biliary drainage as an emergency and temporary treatment of the acute suppurative cholangitis.

Acute Disease↗
PubMed1989

[1-step endoscopic laser papillosphincterotomy with endoscopic biliary drainage].

Two patients with obstructive jaundice are presented. They had cancer of the large duodenal papilla and choledocholithiasis with edema and deformity of the papilla. Endoscopic laser papillosphincterotomy with "Nd-YAG" laser and one-step endoscopic biliary drainage--endoprosthesis of the common bile duct and naso-labial drainage, respectively--were performed. The importance of laser papillotomy in patients, in whom electropapillotomy can not be accomplished or will not give satisfactory results, is emphasized. Analysis is made of the periodic medical literature on this problem. Report is made for the first time on combining two endoscopic methods--laser photocoagulation and endoprosthesis in benign and in malignant stenoses of the papilla, realized in one act.

Aged↗
PubMed1989

[Transendoscopic mechanical lithotripsy in choledocholithiasis].

When there are large stones in the common bile duct or constrictions of the bile ducts the stones very often cannot pas spontaneously or after an endoscopically performed sphincterotomy. In 54 patients after an unsuccessful attempt to extract the stone with the Dormia-basket endoscopic mechanical lithotripsy was performed followed by balloon extraction of the fragments, balloon dilatation of the constricted sectors of the bile duct and securing a bilionasal drainage for prophylaxis of cholangitis. The mechanical lithotripsy was successful in 50 of the patients (92.4%). The jaundice and the cholestasis decreased up to the 10-th day and the cytolytic enzymes became normal. Complications occurred in 2 patients (4%)--hemorrhage up to the 12-th hour after the manipulation. The author recommends, in cases of unsuccessful stone extraction by endoscopic sphincterotomy, the mechanical lithotripsy in combination with balloon extraction of the fragments, balloon dilatation of the constricted sectors of the bile duct and nasobiliary drainage for washing the bile ducts, prevention of bile duct occlusion and treatment of cholangitis in cases of unsuccessful extraction by endoscopic sphincterotomy.

Adult↗
PubMed1987

[Effect of different lighting regimens in the commercial raising of breeders].

Studied was the effect of illumination of varying length and intensity under the industrial raising of broilers. It was found that the use of an illumination programme with an interrupted light regime and low intensity of light affected the live weight, feed intake per unit of produce, and morbidity and mortality rate. The economic effect produced with the introduction of an illumination programme with an interrupted light of low intensity after the first week of BTR-3 regulation consisted in the increase in the production results in the conditions of industrial broiler arising.

Animal Husbandry↗
PubMed1987

[Effect of the bacterial count in the air on chickens and laying hens raised commercially].

Investigations were carried out to establish the amount of bacteria in the air on the premises for raising young birds and laying hans as well as in the respiration organs of the birds. Attempts were made to lower the microbism on the premises through the aerosol spray of Lugol solution. It was found that under industrial conditions there existed a rising trend with microbism both on the premises and in the respiratory organs of the birds, parallel to the advance in age which contributed to the enhancement of mortality rate and the drop of productivity. The use of Lugol solution in the form of spray was shown to produce a favourable effect on the health and productivity of birds.

Aerosols↗