فصلنامه ابن سینا
سال دوازدهم شماره 1 (پیاپی 31، بهار 1388)

There are several evidences of the effect of radiofrequency fields on organic functions and some reports about diseases in radar workers. The aim of this study was to evaluate the effects of microwave exposure in radar workers of IRI Air Force. In this descriptive cross-sectional study, 157 radar workers were enrolled by the convenience sampling method. A three sections information form was used for data collection which included demographic information, general and specialized examinations, and laboratory tests. Data were entered to computer after gathering the complete forms and were analyzed by SPSS software. The most common symptoms among 157 radar workers were fatigue (58.3%), blurred vision (49.4%), and weakness (42.9%). The vision problems were found in 71 cases (45.8%) and 38 personnel (24.5%) suffered from cataract. Skin diseases were observed in 38 personnel (25%). There was a history of abortion in eight personnel's wives (5.2%) and four cases suffered from sterility. The complete blood counts were in normal range. The radar workers are exposed to radiofrequency fields for a long time and may be affected to its different biological consequences such as neurological or ophthalmologic complications. It is necessary to regulate standards about exposure and protection for radar and also to perform more careful control and follow-up for exposure complications.

One of the most sensitive and costly carriers are pilots، such that any time and due to any reason a pilot is unable to accomplish his duty، practically all prior investments have been wasted. In this study we have tried to medically analyze the disability and early retirement in the IRIAF pilots. In this study the personal and work information of all the pilots that are disable or have early retirement due to medical reasons between 1371 and 1382 have been studied and analyzed by the SPSS software. Out of the 49 disable pilots most (39 people) were tactical fighter pilots. The variation in profession was statistically significant (P<0. 01). Most of the personnel studied were colonels (24 people or 49%) and the variation in military insignia was statistically significant. The average years at service were 23. 86 and the average years of service that were left unaccomplished were 6. 14. The most unaccomplished years in service were 10 (20. 4%) and in total more than 201 years of service had been lost. Comparison of the pilot''s average years of disability and those of other personnel shows no significant statistical difference in this studied parameter. The difference in the spread of heart disease in our study (46. 9%) with that study (38%) was statistically significant. Considering the results obtained the least average service age and most of the disable and early retired pilots of all professions were tactical fighter pilots، so special attention to them seems necessary. The most popular reason for disability and early retirement were found to be heart disorders. It is advised that for the better health of this group and decrease in cost، prevention and more exact heart checkups in the annual checkups be considered.

Music groups of army are often exposed to more than 85 decibels voices which is defined as sound pollution. However، there are not any use of hearing protections in this group. Because there was not accurate information about the prevalence of hearing problems in the music group، the purpose of this study was to survey the prevalence of hearing impairment and its types among music group of IRI Air Force. In this descriptive observational study، hearing condition of all personnel of music group who enrolled the study، was evaluated by pure tone audiometry and acquired information along with age and employment date of them were entered the computer and analyzed by SPSS Software. Of 71 personnel of music group، 24 (34. 3%) had hearing impairments. Also there was not any significant relationship between duration of employment and hearing impairment. The most common problem was mild disorder in hearing threshold levels (HTL) (62. 5%)، followed by mild disorder in the middle frequencies (33. 3%)، moderate disorder in HTL (4. 1%)، severe disorder in HTL (4. 1%) and air-bone gap (4. 1%). Hearing disorders due to noise in army music group is the same as other noisy jobs. This can indicate the need of noise protection devices and periodical checkups for prevention of this disorder.

Physically induced joints pain is a relatively common finding in military personnel. Occupational factors like level of activity، style of job performance and individual factor like physical composition of body، sex are described as the risk factors. In this study we describe the pattern of joint involvement in the military personnel and compare it with non-military patients. This descriptive-comparative cross-sectional study was performed in 3 military and 3 non-military hospitals in a 3 year period. A census of all patients with confirmed physically induced joint pain was performed. Patient data in 3 fields of demographic data، occupation (job category) and involved joints was requested. Using frequency matching for sex، age، height and weight 1230 patient enrolled in the study. Analysis performed using chi-square test. 640 (52%) patients were military patients and 630 (51. 2%) patients were male. No significant difference was present in mean age، weight، height and work experience. Male gender was predominant in military patients (53. 1%) but in non-military patients it was 49. 1%. Distribution of military patients in job categories of combat، logistic، engineering، cultural، security and non governmental were 179 (28%)، 218 (34%)، 102 (16%)، 51 (8%)، 90 (14%)، 0% respectively. The distribution has significant association with being military and non-military patients (p<0. 001). According to the finding of this study، military patients especially male patients and the ones in security and combat categories are under more physical stress and pressure and are more prone to have joints injuries. Routine evaluation of physical and health and general health، using selected personnel with appropriate body composition in mentioned job categories and enhancement of physical fitness should be considered in military personnel to prevent such injuries.

The two major threat classes of chemical weapons are mustard gas and the nerve agents. Mustard was used in World War I، and there is an extensive human database on it. The fact that mustard gas is a carcinogen and readily produces a variety of chronic or persistent effects was not fully appreciated until after the war and following extensive human occupational exposure prior to World War II. Many of the toxicologic studies and human toxicity estimates for both mustard agents were generated for the purpose of developing chemical agents that would quickly produce maximal casualties in the least sensitive male soldier. We must also consider the effects of chemical agents on civilian populations and the effects of prolonged exposures to relatively low doses. These materials have always been extremely potent and efficacious. Their toxicity has not changed، but our perception of it has. Mustard gas is one of alkylating agents which has been used against soldiers in wars. This hazardous agent has uncopensable effects on humanbeing and other organisms. Mutagenicity، carcinogenicity and teratogenic effects of this toxic gas has been investigated by many scientists، but still there remained unknown facts about mutagenic effects of sulfur mustard and its metabolites to be solved. In this study، to find an easy، quick and efficient test to indicate mutagenicity of sulfur mustard and its metabolites، 20 urine samples were collected from injoured patients who were exposed to mustard gas in Sardasht area. Samples were assayed for the presence of mutagens by Ames and Fluctuation tests using bacteria strains salmonella typhymurium TA98، TA100 and TA102. This study showed that salmonella typhymurium TA102 is the best strain to be used for detection of mutagens in urine samples of patients exposed tro mustard gas. It was clearly shown that fluctuation test was much more sensitive test than Ames test in detecting low doses of mutagen.

Each occupation، besides work activities، is the sequence of opinions and behaviors related to the work which depends on the whole experience of our life. A job like pilotage is the combination of personality and work activities. The more a pilot''s personality is in accord with his work activities، the more the output of his occupation will be increased. This is the main objectice of the psychologists in the field of pilot evaluation and election. Psychological assesment of the flying pilots must illustrate two points: lack of mental disorder and motivation quality for flying. In other words who can fly and who wants to fly. The first goal that is assurance of no psychological disorder، has been Studied by psychiatrists and the second goal، quality and level of motivation، has been Studied by psychologists. Generally، the stages of psychological evaluation and election، consists of these factors: Preliminary interview، psychiatrist evaluation، aptitude and neuropsychological tests، organized interview and personality tests and mental compatibility.

eisseria meningitidis is a leading cause of bacterial meningitis and other invasive bacterial infections، both in the United States and worldwide. The role of the meningococcus as a cause of bacterial meningitis has become more important in recent years with the declines in meningitis caused by Haemophilus influenzae type b and Streptococcus pneumoniae because of the introduction of new conjugate vaccines، Listeria because of efforts to reduce the contamination of food with L. monocytogenes، and group B streptococcus because of the use of chemoprophylaxis during parturition in women. The development of a pneumococcal vaccine six decades ago demonstrated the feasibility of vaccine prevention of invasive encapsulated bacterial diseases. Purified polysaccharide vaccines for serogroups A and C N. meningitidis were developed several decades later. Early vaccines were poorly immunogenic apparently because the polysaccharides that were used were of low molecular weight، whereas vaccines made from polysaccharide with a molecular weight over 100،000 had excellent immunogenicity. Meningococcal conjugate vaccines، are typically T-cell dependent، which as regards of immunologic improvements over polysaccharide vaccines. The carrier proteins used for meningococcal conjugate vaccines have included tetanus toxoid protein، diphtheria toxoid، and diphtheria cross-reactive material (CRM) 197. The immunogenicity of a variety of outer membrane protein- based serogroup B vaccines has been studied. In an evaluation of three doses of a Cuban B: 4: P1. 15 vaccine and a Norwegian B: 15: P1. 7،16 showed that more than two-thirds of children and adults had at least a fourfold rise in SBA، as did at least 90% of infants.

The gas contained in the body cavities is effected by external pressure change، thus with decreasing atmospheric pressure، during ascent or loss of cabin pressure، the gas volume increases and during descent the volume of the gas decreases. The connection with the external environment is achieved in different manners for different cavities. During external pressure change the gas pressure inside the cavities has to reach equilibrium with the air pressure outside. In this review، the gas expansion and the theories of its effect on body cavities are discussed and the body cavities and classified in two distinct categories: Semi-closed cavities and closed cavities. The middle ear، the paranasal sinuses and the lungs are studied in the former and the alimentary canal and the teeth are discussed in the latter.