Fractal analysis of STM images of photochemical polymer of coniferyl alcohol.

Fractal analysis was applied to images of photochemical lignin polymer obtained using scanning tunneling microscope. We studied the polymer obtained in vitro by ionic mechanism through UV radiation--induced polymerization. The analysis showed the regularity of the lignin-like polymer at different levels of organization. At the 95% confidence level, there was no significant difference in the fractal dimension between images representing different organizational levels of photochemical lignin. That means that lignin produced in in vitro conditions by photochemical mechanism of synthesis, has a fractal structural organization. The obtained values of the fractal dimension are in good agreement with the theoretically predicted value for the polyaddition and polycondensation mechanism of polymerization, known as the bulk model.

Fractal analysis of STM images of lignin polymer obtained by in vitro synthesis.

Lignin, the structural polymer of the plant cell walls, is produced by free radical polymerization of phenolic alcohols, catalyzed by different peroxidases. The mechanism and the structural organization of lignin in the cell have not been completely understood. In this study we applied fractal analysis to images of lignin polymer obtained using scanning tunneling microscope. The analysis showed the regularity of the polymer at different levels of organization. According to the results obtained, at the 95% confidence level, there is no significant difference in the fractal dimension between images representing different organizational levels of lignin. In other words, lignin produced in in vitro conditions has fractal structural organization and, consequently the polymer can be expected to be regular in in vivo conditions. The value of the fractal dimension 1.929 +/- 0.021 is in good agreement with the theoretically predicted value for polyaddition and polycondensation mechanism of polymerization. The mechanism of in vivo lignin synthesis is discussed in terms of various experimental and theoretical evidences. In this paper, we could show that fractal analysis of the lignin polymer is a useful complementary approach to the experimental data collection in structural and phenomenological studies.

[Surveillance of communicable diseases using a computer database of reported cases]. / Pracenje zaraznih bolesti pomocu racunarske baze podataka prijave obolelih.

Epidemiology services during the surveillance of communicable diseases collects of different sorts of data, which are used for an analysis of epidemiologic situation. Those data are the starting point for timeline control and preventive activities. Data processing of notified communicable diseases cases provides information on types of diseases, number of cases, time and place of their occurrence. Manual data processing, used till 1993, was slow, unreliable and considerably decreased the efficiency of epidemiology service activities. In this paper we have set the hypothesis that is possible to form a computerized database with the following aims: to form user friendly computerized database model for those without knowledge in using computers: to get output spread sheets with information needed for epidemiologic situation analyses at any time. Database was developed in 1993 and has been used as source of the information in epidemiologic diagnosis process. The significant accuracy, reliability, timelines, and shortening of the time of data processing was achieved. The database can also serve as the initial component for designing an epidemiologic services information network in Belgrade county. In designing such a network it is necessary to form the additional databases of isolated infectious agents and their drug resistance, database of health status of persons under surveillance and database of environmental and sanitary condition in children and youth facilities.

The effects of long-term low-protein intake on gastrin cells of the rat antral mucosa during adulthood.

The effect of experimental protein malnutrition on gastrin producing cells in the antral part of the stomach was studied in male Wistar rats. Isoenergetic diets containing 25% (C-25) or 6% (PD-6) were given in isocaloric amounts during a 4-month experiment. All rats were offered drinking water ad libitum. The results showed that the long-term protein diet did not produce changes in the gastrin cell number. At the ultrastructural level G cells exhibited a decreased size of the nucleus. They were found to have an increased total granule volume density but the volume density of dense-cored granules was lower. The serum gastrin levels were significantly lowered by feeding the low protein diet. These changes are compatible with decreased functional activity of G cells under long-term protein deprivation.

[The effect of captopril on the development of adriamycin nephropathy in rats with spontaneous arterial hypertension]. / Uticaj kaptoprila na razvoj adriamicinske nefropatije kod pacova sa spontanom arterijskom hipertensijom.

The effects of captopril on morphologic changes and clinical course of adriamycin (ADR) nephropathy in spontaneously hypertensive rats (SHR) were examined. After ADR infections rats were divided into two groups: ADR-C group (n = 20) given captopril (60 mg/kg per day) and ADR group (n = 19) receiving no antihypertensive treatment. SHR were examined every 6 weeks. Captopril normalized systemic blood pressure, but failed to prevent proteinuria. It slowed down renal function deterioration in the early stage of ADR nephropathy (weeks 6 and 12), but at the end of the study both groups had the same degree of renal failure irrespectively of whether blood pressure was well controlled with captopril or hypertension persisted. Captopril slowed down mesangial expansion in the early stages of ADR nephropathy, but at the end of the study there was no statistically significant difference between these two groups. Treatment with captopril also reduced the development of glomerular sclerosis.

[Modern expert systems and their use in medicine]. / Savremeni ekspertni sistemi i njihova primena u medicini.

During the last two decades, many important results have been achieved in the field of artificial intelligence. One of the most important results is development and application of programs known as expert systems. Medicine is the one of the fields inwhich expert systems are most frequently developed and applied. This paper describes features of these programs, state of the art in the field of expert systems, and the possibilities of their application in medicine.

[Program package for data follow-up about patients with implanted hip endoprosthesis]. / "Paket" programa za pracenje podataka o bolesnicima s endoprotezom zglobova kuka.

Modular program package for forming and analysis of data about patients with implanted hip endoprosthesis in Special Hospital for Orthopedics Surgery "Banjica" Belgrade was designed and realized. This program package could be one module of information system in this health institution. Developed package for analyses of endoprosthesis reliability is opened for eventual changes, upgrading, modifications or it is possible to take one segment of this program as autonomous one. Interactive dialogue is completely on serb language, so communication don't required knowledge of foreign language, and it is adjusted for level of knowledge of nurse who will make data registration and updating of database. We use TPK questionnaire as model for a program package. Through years this questionnaire was used for follow-up of implantation of hip endoprosthesis. This questionnaire contains patients identification data, anamnestic and findings data, operative and postoperative data, rehabilitation, and results of periodical controls. The key for patients identification data, anamnestic and findings data, operative and postoperative data, rehabilitation, and results of periodical controls. The key for patient identification in different bases in unique TPK-number-patient number in protocol. By using data from data base, this package allows search, relation estabilishment, and statistical analyses. It is possible to evaluate TPK-questionnaire, and after longer use, to do eventual modifications. All acquired data allow follow-up of implanted endoprosthesis reliability, as well as work reliability of medical team.

[Review of new expert systems in medicine]. / Pregled novijih medicinskih ekspertnih sistema.

The paper describes a number of features of contemporary medical expert systems by examples of some typical medical expert systems developed recently. Along the features themselves, typical application domains and performance of current medical expert systems are also presented.

[Glossary of medical informatics terminology]. / Mali recnik informatike u medicini i zdravstvu.

This paper presents the most frequently used terms in the field of informatics and computer applications in medicine and health care. Out of over 4,000 terms that are frequently used in computer science and allied fields, we have chosen only 108. The criteria has been their usage in this Supplement and better understanding of the presented papers. Each term has its Serbian translation, original English term and short explanation. At the end of the paper is an English - Serbian register and a survey of computer's and informatic's glossaries.

Elevated blood lead in a population near a lead smelter in Kosovo, Yugoslavia.

A survey of residents of a community surrounding a lead smelter has revealed an alarming incidence of elevated blood lead and erythrocyte protoporphyrin concentrations. In particular, children who were less than 3 yr of age were severely affected. Of those children tested in December, 1980, 35% had blood lead concentrations between 50-69 microgram/dl, while an additional 12% had concentrations greater than or equal to 70 microgram/dl, and are, therefore, at risk for severe neurological sequelae.