PubMed Health⌕ Search

Biomedical subjects

A Belán

Publications and source records attributed to A Belán.

At least 19 recordsLinked to original sources
PubMed2003

[Impact factors and bibliometrics of science. Does pure science really exist?].

The impact factor is an artificially created indicator which when applied separately does not achieve the value attributed to it. In its assessment a number of different influences are projected which cause partial mistakes with a cumulative effect. It can have an even worse effect if the impact factor is incorrectly conceived or inadequately handled. Only in a long-term review using specific corrections it can serve to determine really top class periodicals but only within the framework of a single scientific discipline. It is not suitable for comparison of interdisciplinary journals. It should be used very carefully in the evaluation of authors. However it is still used in various types of administrative management. From the submitted paper it may seen that with a certain amount of overstatement it is personified and acts on its own. Its personification is homo sapiens scientometricus who evaluates himself as well as his environment which is represented by mere homo sapiens scientificus. In addition to the impact factor the authors discuss also other indicators and some aspects of scientometry.

Bibliometrics↗
PubMed1997

[Percutaneous transluminal angioplasty of the renal artery in transplanted kidneys].

UNLABELLED: The objective of the work was to evaluate the contribution of percutaneous transluminal angioplasty (PTA) to treatment of hypertension and the graft function of a transplanted kidney. Angioplasty of the graft artery was performed in 39 patients. Technical success rate: 85%. COMPLICATIONS: 13%--in particular during the first years after introduction of the method. Twenty seven patients were followed up on a long-term basis. Changes of the median arterial pressure (MAP) were evaluated as well as glomerular filtration (GF) assessed by creatinine clearance. Mean values: [table: see text] A statistically significant (p < 0.01) reduction of the median arterial pressure (drop by > 10 mm Hg) along with reduction of the number of antihypertensive drugs was recorded in 70% of the patients during the first year and in 80% kidney recipients in investigations extending beyond one year. A significant increase of glomerular filtration (by > 20%) was found in 40% of the patients, on average the rise was insignificant. During the follow up period 13 kidney recipients were transferred to a dialyzation programme due to failure of the grafts as a result of rejection. CONCLUSION: Percutaneous transluminal angioplasty of a stenosis of the graft artery is the method of first choice in the treatment of hypertension. It is of fundamental importance also in rare cases in order to preserve or improve graft function and thus delay dialyzation treatment.

Adult↗
PubMed1995

[Renal hemodynamics and albuminuria in patients with arterial hypertension].

BACKGROUND: The cause of hyperalbuminuria in hypertonic patients can be functional or irreversible structural changes. The objective of the present investigation was an attempt to differentiate these two possibilities by comparing data of hypertonic patients with normal albuminuria (albumin excretion < 20 micrograms/min) and those with microalbuminuria in patients with renovascular hypertension by comparing findings after successful percutaneous transluminal angioplasty of the renal arteries (n = 8). METHODS AND RESULTS: The authors examined 20 patients with normal albuminuria (12 men and 8 women, mean age 46 years) and 20 patients with microalbuminuria (12 men and 8 women, mean age 49 years). Of these patients 8 were examined repeatedly after angioplasty. The examination was made in the morning, renal haemodynamics were assessed by the infusion technique (clearance of polyfructosan and paraaminohippuric acid), in blood and urine the albumin and IgG concentration (bromcresol purpur-Lachema Brno and immunoturbidometrically-Tina-quant Boheringer Mannheim). In hypertonic patients with microalbuminuria a significantly higher (p < 0.001) IgG excretion was found (14.1 as compared with 5.12 micrograms/min.) and a reduced ratio of IgG clearance to albumin clearance (p < 0.001), 0.73 as compared with 1.60. After successful angioplasty of the renal arteries there was a significant drop of the blood pressure (p < 0.05) and of the renal vascular resistance as well as a significant decrease of albuminuria (p < 0.05) on average from 137 to 48 micrograms/min. The quantitative improvement of albuminuria, however, did not go beyond the discrimination value for microalbuminuria. CONCLUSIONS: The results suggest that microalbuminuria in hypertensive patients is as a rule a manifestation of structural renal changes, while also functional and reversible changes participate. The asset of treatment of hypertension by angioplasty of the renal arteries was manifested not only in the renal haemodynamics but also by reduced albuminuria.

Albuminuria↗
PubMed1992

[Coronary surgery at the Institute of Clinical and Experimental Medicine].

In 1971-1991 in the Institute of Clinical and Experimental Medicine 2386 operations on account of IHD were performed. 2154 aortocoronary bypasses, 6 Vineberg operations, 51 valvular prostheses and aortocoronary bypasses, 128 resections of left ventricular aneurysms and 47 closures of post-infarction perforations of the interventricular septum. The mortality from aortocoronary bypasses during the entire period was 6.9%. The authors discuss different periods, changes of the operative technique and contemporary views on surgical treatment of IHD.

Cardiac Surgical Procedures↗
PubMed1991

[Precordial S-T stress mapping in the evaluation of the effects of percutaneous transluminal coronary angioplasty].

The morphological impact of percutaneous transluminal angioplasty (PTCA) on the treated artery is closely checked by coronary arteriography. Indirect non-invasive evaluations are made possible by electrocardiography, isotope methods and echocardiography which are the commonest visualization methods. The authors used a precordial S-T load map. After complete revascularization following PTCA there was a significant drop of the sum of S-T depressions and in some members of the group it reached normal values. The S-T load map is a suitable non-invasive procedure for monitoring the effect of PTCA.

Adult↗
PubMed1990

[Complications of percutaneous transluminal coronary angioplasty].

The most frequent complication of percutaneous transluminal coronary angioplasty is acute obstruction of the artery to be dilated. The authors present their experience with the solution of this situation. In a group of 154 consecutive patients with chronic stable angina pectoris a sudden occlusion was observed in 7.7%, infarction in 5.8% and the necessity of operation arose in 5.2%. A significant position in the solution if these complications is held by cardiosurgical revascularization. As to pharmacological treatment, it is useful to administer a combination of nitrates, calcium channel antagonists and thrombolytic treatment.

Angioplasty, Balloon, Coronary↗
PubMed1990

[Therapeutic embolization of the venous bed using Vilan 500 in animal experiments].

The experiment in four dogs verified a suitability of the Czechoslovak preparation Vilan 500, a copolymer of polyvinyl acetate - polyvinyl alcohol in 93% ethanol, for the embolism of venous vascular bed in the percutaneous, transfemoral catheterization way. In all four cases there was a complete occlusion of embolized spermatic or pararenal veins, verified by a control angiography after one hour and after three months. The prepared venous samples were also examined by histology and changes indicating intraluminar thrombotization and subsequent fibrous reconstruction were observed. In view of the results reached it may be concluded that the catheterization technique and the use of Vilan 500 is suitable as an alternative of non-surgical solution of varicocele.

Animals↗
PubMed1989

[Long-term results of percutaneous transluminal angioplasty in a peripheral region].

The authors performed, in the period of 10/1980 to 12/1985, 102 PTA interventions in 95 patients in the peripheral region. The lasting clinical improvement of early and long-term duration was expressed by the Life-table method. In the whole cohort, 95% of patients proved to be improved clinically in the early period (3 months after the intervention), while 70% of patients were improved for long-term period (up to 66 months). The authors also compare the results reached in PTA of pelvis vascular bed and femoropopliteal region. In the PTA of pelvis vascular bed, improved clinical condition in the early period was reached in 95% of patients, long-term improvement was observed in 73% of individuals. In PTA of femoropopliteal region the early period showed improvement in 96% of patients, the long-term period indicated improvement in 52% of subjects.

Adult↗
PubMed1989

[The significance of the systolic gradient value in percutaneous transluminal angioplasty].

In the period of 10/1980-12/1985 the authors performed 102 percutaneous transluminal angioplasty operations on 95 patients in the area of pelvic vascular bed and arteries of lower extremities. The authors evaluated the values of systolic gradient before and after the intervention. Computer assisted statistical methods were used in the search of relationship between the value of systolic gradient and duration of clinical improvement after the surgery. There was not any statistically significant relation between the values of S-gradient before and after PTA and the long-term fate of the patients treated by this method. The authors are of the opinion, though, that measuring this value provides a useful information in the course of surgery.

Adult↗
PubMed1989

[Recanalization and dilatation in chronic occlusion of the renal artery: 2 case reports].

The authors describe their experience in two cases of mechanic desobliteration and subsequent percutaneous transluminal angioplasty in a chronically occluded renal artery. It has become obvious that although this surgery has been so far performed only rarely it is technically viable and may exert a favourable therapeutic effect on hypertension of renovascular etiology as well as angioplasty of stenosing lesion of kidney arteries. The paper also discusses a possibility of influencing renal function by this method. The authors arrive at the conclusion that recanalization of a chronic occlusion of renal artery extends the presently relatively stabilized indications for percutaneous transluminal angioplasty in this localization.

Adult↗
PubMed1989

[Percutaneous transluminal angioplasty of the branches of the aortic arch].

Percutaneous transluminal angioplasty (PTA) takes its stable position in the therapy of obliterating arterial diseases. Its indication areas considerably extend. The authors present a survey of their experience and the results of PTA of arteries supplying the brain and upper extremities. This surgery was made in 29 patients on 31 arteries. The authors consider PTA on a. subclavia as a method of choice. In the angioplasty on a. vertebralis there is a very low risk in correctly indicated cases. An atherosclerotic stricture of a. carotis interna is not considered suitable for PTA for the risk of embolism from the exulcerated plaques. However, the method may be used with advantage in the stenosis based on fibromuscular dysplasia and in some cases of early restenoses in a. carotis interna after previous endarterectomy. The authors arrive at the conclusion that PTA, if correctly indicated, is a safe method even in arteries supplying the brain and upper extremities. No complication was observed in the reported group.

Angioplasty, Balloon↗
PubMed1989

Creatine kinase kinetics and myocardial infarction in different regions of the left ventricle.

The interval from the onset of infarction pain to culmination of plasma creatine kinase activity (t-peak) was measured in 68 patients with their first myocardial infarction. There is a major difference in this parameter in patients with infarction in the area of the right coronary artery and that supplied by the left anterior descending coronary artery (LAD). While, in 29 patients with infarction in the right coronary artery area, t-peak was 17.7 +/- 4.7 hours, in 39 subjects with infarction in area supplied by the LAD, t-peak was 13.2 +/- 4.6 hours (p less than 0.001). The type of thrombolytic treatment (intravenous or intracoronary, used no difference, just as the time from onset of pain to start of therapy, infarct size and presence or absence of collaterals. A detailed analysis of creatine kinase culmination in relation to the type of artery recanalization is given. The authors conclude that, besides the known factors, creatine kinase culmination is influenced also by the necrosis site, a fact somewhat modifying the informative value of this parameter. However, explanations of this phenomenon are only hypothetical at the present time.

Creatine Kinase↗
PubMed1989

[Acute myocardial infarct and the kinetics of creatine kinase].

The authors criticize contemporary views on creatine kinase kinetics in relation to the patency or occlusion of the coronary artery in the area of the infarction focus. In the investigation proper the time needed to achieve the peak plasma creatine kinase activity after the onset of infarction pain in patients with necroses in different areas of the left ventricle is assessed. Although the interpretation of the observed phenomenon is not clear so far, this finding makes the informative value of the hitherto used time parameter of the kinetics of this enzyme doubtful, in particular in thrombolytic treatment of myocardial infarction. In practice it is thus not possible to evaluate the restored patency of the artery to the necrotic focus on the basis of the above parameter.

Coronary Vessels↗
PubMed1989

A comparison of radionuclide and contrast left ventriculography and coronary angiography in patients after myocardial infarction.

61 patients after myocardial infarction were investigated by selective coronarography, contrast (LVG) and gated radionuclide ventriculography (RNV, rest and mild exercise). Left ventricular ejection fraction (LVGEF and RNVEF, resp.) and regional contractility disturbances were determined (in RNV by Fourier transform and factor analysis). A high correlation of rest LVGEF and RNVEF was found, with lower RNVEF values. A significantly lower rest RNVEF with no change during exercise was observed in comparison to 29 control persons. The ability of RNV to detect regional wall contractility impairment was nearly the same as that of LVG. RNVEF was negatively influenced by LAD obstruction and furthermore in combination with other main coronary artery jeopardy. Gated RNV is a valuable noninvasive method that could replace contrast LVG in the assessment of left ventricular function.

Adult↗
PubMed1989

[Magnetic resonance--personal experience with its use in otorhinolaryngology].

The authors present their initial experience with the visualization by magnetic resonance (MR) in otorhinolaryngology in the CSR. Due to multidimensional and high contrast visualization, MR facilitates greatly spatial orientation as regards localization and size of the pathological process. Its importance otorhinolaryngology is in particular in the diagnosis of neoplastic diseases. For some localizations of tumours MR is the method of choice.

Adult↗