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991.
The magnitude of the threat that violence and war pose to the health, the quality of life, and the very survival of humanity is obvious. A number of scientific disciplines have provided, each through its own methodology, insights into the causation, genesis, and dynamics of violence and war. Although epidemiological and psychological methodologies received priority, the multidisciplinary approach to this problem seems to be the most appropriate. This essay attempts to approach holistically the study of epidemiology of violence and war and the ways of preventing these severe problems of the contemporary society. Conceptual models of the causative mechanisms and dynamics of violence and war, mapping the various psychic, social, and environmental factors, are presented. These models, besides advancing abstract ideas, also provide a concrete framework for determining and exploring the interactions and dynamics of the factors and processes which lead to violence and war. The types of interventions outlined for control and prevention are intended to make an impact upon "critical points" within the dynamics of the process which produces violence and war, and are conceived to be implemented on both the national and international level. The importance of family, community, and school influences is considered, but the role of international organizations, including the United Nations, and other governmental and non-governmental organizations is also stressed. Discussion is focused on the factors which favour peace and hamper aggression, on "internationalization" and global society versus xenophobia and nationalism. The conclusions state that there is sufficient knowhow to devise and implement a reasonable and effective international programme for the control and prevention of violence and war, provided there is adequate public and political willingness and support.  相似文献   
992.
We measured 14 rowers and divided them into two groups according to age and years of training. Our goal has been to establish the influence of several years of programmed training on the structure of the body, oxygen carrying capacity and oxidation capacity of muscle cells, the chemical composition of blood and characteristics of pulse and lactate curves in rowers. As to the structure of the body, the two groups did not differ if we equalised them according to body height. Differences existed in the determinants of oxygen carrying capacity and oxidation capacity of muscle cells. Older rowers had lower pulse at rest, higher step test index, lower pulse immediately after the step test and in the last minute of the test on a bicycle ergometer and higher maximal oxygen pulse. While at rest, no significant differences between the groups were observed in most of the analysed substances in the blood serum. With the increase of age and training period an increase of the concentration of creatinin and activity of creatine kinase and lessening of the activity of alkaline phosphatase was noted. Length of training period lowers the levels of cholesterol and free fatty acids and increases the level of triglycerides in blood serum. An increase of the activity of creatine kinase and lactate dehydrogenase and the formation of a specific pattern of isoenzymes was observed. The pulse and lactate curve flattened and moved to the right.  相似文献   
993.
In order to study left ventricular hypertrophy patterns in obese hypertensives, we examined 132 patients with essential hypertension by 2D, M-mode and Doppler echocardiography. The patients were classified in four comparable groups, corresponding to the values of Quetelet's body mass index (BMI) and grades of obesity. More obese hypertensives had on average larger left ventricles with thicker walls and larger left atria than less obese, or lean ones. Left ventricular mass increased significantly and progressively with advancing grades of obesity, but relative wall thickness (wall thickness/cavity size ratio) did not diminish. Doppler echocardiography revealed significantly higher prevalence of left ventricular diastolic dysfunction among obese than among lean hypertensives. In the second part of our study, we analyzed the subgroups defined by the severity of hypertension and the age of the patients. The correlation of the indices of left ventricular and left atrial hypertrophy with the BMI values was considerably better in the group of moderate than in the group of mild hypertension. The r values were 0.62 vs. 0.22 for left ventricular mass and 0.64 vs. 0.26 for left atrial dimension. The group of patients with severe hypertension was characterized by left ventricular cavity enlargement in correlation with increasing BMI values, but without corresponding left ventricular wall thickening. So called left ventricular "eccentricity index", as the reverse value of relative wall thickness, correlated well (r = 0.76) with the BMI values. The indices of left ventricular hypertrophy correlated with the BMI values slightly better in middle age groups than in the groups of the youngest (< or = 30 years) or the eldest (> or = 61 years) hypertensives. In conclusion, eccentric left ventricular hypertrophy does not seem to be a distinctive feature of hypertensive heart disease in obesity. There is only some tendency toward the "eccentricity" of left ventricular geometry which becomes more apparent in more severe forms of hypertension, especially in very obese persons.  相似文献   
994.
The inclination between the posterior wall of the articular eminence and the referential plane (Frankfurt line) was measured on 137 dry skull specimens (78 with complete dental arches and 59 edentulous). Both left and right joints were measured using direct craniometric method. The results were compared with respect to the loss of teeth, side and sex. A large range of measured values of the eminence inclination shows great individual differences, so that the mean values can have only orientational significance. The mean value of eminence inclination for all measured specimens was 61.9 angular degree. The difference between the two groups established upon dental status is very small and without any statistical significance (P > 0.05). The right joint shows a slightly steeper eminence inclination compared to the left one, but without any statistical significance (P > 0.05). Asymmetry between the right and left joint appears almost as a rule, while maximum measured differences reach up to 33 degrees, with mean absolute difference of 6.9 degrees. The group of edentulous specimens shows a greater symmetry and less differences between the left and right joint, which indicates that different bimechanical conditions in the joint, due to tooth loss might lead to remodellation of the articular eminence. The eminence inclination was significantly steeper in male specimens in all subgroups (P < 0.001), which confirms sexual dimorphism.  相似文献   
995.
The principal objective was to measure the magnetic fields occurring in dental surgeries at simultaneous subtraction of direct ground component of the magnetic field. A specifically designed instrument with the Hall probe was used for the measurement. It consisted of two amplifiers and a low frequency filter. Its task was to measure mean square values of the field (RMS) dependent on the position in space. Qualitative and quantitative analyses of the investigated variables enabled making conclusions about the magnetic fields in dental surgeries. A number of studies have shown that many dental instruments produce radiation with magnetic field higher than 40 G, at a significant decrease in power of the magnetic field with increasing distance from the source. It has also been reported that instruments of older generations produce stronger magnetic fields than do the new ones.  相似文献   
996.
During the period from 1995 to 1999, 64 patients were treated for ectopic pregnancy. All patients admitted to the department passed the same procedure including (complete preoperative laboratory findings, Beta HCG, serum progesterone and transvaginal colour Doppler). In patients who had ultrasound finding typical for ectopic pregnancy in combination with positive Beta HCG, conservative treatment was primarily done. In the rest of the patients, Beta HCG was tested every second day and in combination with the clinical and vaginosonographical findings the patients underwent diagnostic or operative laparoscopy. Out of 64 patients 36 had visible ectopic pregnancy when admitted to the clinical department. Three patients had no visible ectopic pregnancy neither at the time of their admission to the department nor at the time of laparoscopy. One of them had cervical pregnancy and the other two had pregnancies in the uterine part of the tube. The patient with cervical pregnancy was treated with metrotrexat (MTX) 12 mg daily in 5 doses. One patient with cornual pregnancy was treated with high doses of oxytocin infusion in combination with MEB intravenously 3 x 1 amp. The other patient with cornual pregnancy underwent laparoscopy with cornual resection and salpingectomy. Four of other tubar pregnancies were treated with metrotrexat 12 mg/day for 5 days. Other ectopic pregnancies were treated as follows: 36 laparoscopic salpingectomies, 10 laparoscopic salpingotomies with ovum expression, 9 adnexectomies by laparotomy, and 2 laparoscopic adnexectomies.  相似文献   
997.
In this paper the success rate of implant therapy in various bone regions is discussed. The objective is to determine whether differences existed in success rates of cylinder implants placed in different areas in the both maxilla and mandible. Forty four patients have been treated and reviewed five years after the placement of the fixed prosthetic restoration. The patients were provided with a total of 92 implants. Results from this study show very low survival rate for implants placed in anterior region of maxilla (55.6%) after five years. It is concluded that simple cumulative follow up studies do not entirely correspond to actual situations, positioning the implants has an important role in the planning of the implant therapy and that important factor for force compensation is not only the surrounding bone density, but also the region of the jaw where the implants are placed.  相似文献   
998.
Biomechanical studies have found wide application and solved many problems in dental medicine. An interdisciplinary approach has allowed an ever-faster progress in the field. The aim of this study was to point out the advantages of holographic interferometry. With the use of this method, the study object is observed as a whole rather than as a substrate, thus providing a three-dimensional holographic image visualizing the load transmission from one jaw to another, tooth pressure against the alveolus, and strain of Sharpey's fibers, and yielding precise data on deformities, dislocations and force distribution.  相似文献   
999.
In this epidemiological study the caries status of 12-year-old children was compared over time for the years 1968, 1973, 1980, 1985, 1990, 1991 and 1999. The mean number of decayed, missing and filled teeth (DMFT) decreased from 7.0 in 1968 to 2.6 in 1991. From 1991 to 1999 and increase of DMFT 2.6 in 1991, to 3.5 in 1999) has been seen which is result of war in Croatia and reorganisation of health care delivery system. With the expected continuing decline in the prevalence and severity of oral diseases, one of the main problems in the future seems to be the transition of the oral health care delivery system from a disease-oriented system to a health-oriented one.  相似文献   
1000.
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