This paper presents a mathematical model for an inventory control system in which customers’ demands and suppliers’ service time are considered as stochastic parameters. The proposed problem is solved through queuing theory for a single item. In this case, transitional probabilities are calculated in steady state. Afterward, the model is extended to the case of multi-item inventory systems. The...

background : myocardial infarction in young age is increasing. identifying risk factors could be important for health promotion. we studied classic atherosclerotic risk factors in premature myocardial infarction. methods : in this matched case-control study, which was conducted from 2005 to 2007 in birjand county, the east of iran, atherosclerotic risk factors ( hypertension , family history of...

background: due to complex causal framework of neonatal mortality, improvement of this health indicator is quite gradual and it's decreasing trend is not as great as other health indicators such as infant and under 5 mortality rates.this study was conducted to evaluate neonatal mortality risk factors based on nested case-control design. methods:  the study population was 6900 neonates who were ...

psoriasis is a chronic relapsing disorder that involves the skin, nails and joints. with regard to the role of the immune system in psoriasis, the current study compared serum ige concentration in patients with psoriasis with control group. current case-control study was conducted in dermatology clinic of razi hospital, tehran university of medical sciences, tehran, iran in 2012. fifty-eight pa...

objective: although numerous studies have found higher rates of abortion and still births following consanguinity (familial marriages), the question of whether consanguinity significantly increases the risk of neonatal death has inadequately been addressed.this study aims to evaluate familial marriage effects on neonatal death in rural areas in iran. materials and methods: i n this nested case-...

Background There is ample evidence that since the turn of the millennium German health policy made a considerable step towards prevention and health promotion, putting the strategies of ‘personal empowerment’ and ‘settings based approach’ high on the federal government’s agenda. This phenomenon has challenged the role of ethics in health policy. Concurrently, increasing relevance of the Concept...