objective headache is a frequent symptom in children and adolescents. migraine is one of the most common types of primary headache disorders in children that at times can be extremely disabling. many clinical features of migraine in children differ from that starting in adulthood. this review discusses the epidemiology,clinical features, management, and prognosis of migraine headache in childre...

acetonitrile used as a solvent in manufactures and affects to central nervous system from inhalation exposure. the aim of this study was to develop a micro-solid phase extraction method for  the determination of acetonitrile in the air matrix. the sampling was performed with a small diameter fused silica fiber coated with a thin film of stationary phase and was subsequently desorbed and analyze...

background: supplementation of luteal phase with progesterone is prescribed for women undergoing routine ivf treatment. objective: the objective of this study was to compare the efficacy of three types of progesterone on biochemical, clinical and ongoing pregnancy rates and abortion and live birth rates. materials and methods: a prospective randomized study was performed at royan institute betw...

background: the application of luteal phase supplementation hormones to increase the implantation rate is on debate among researchers. objective: in this study, the morphological and morphometrical assessment of superovulated mice endometrium were investigated at window implantation period superovulated mice. materials and methods: female mice were superovualated then were mated with vasectomiz...

The aim of this paper is to minimize output phase noise for the pure signal synthesis in the frequency synthesizers. For this purpose, first, an exact mathematical model of phase locked loop (PLL) based frequency synthesizer is described and analyzed. Then, an exact closed-form formula in terms of synthesizer bandwidth and total output phase noise is extracted. Based on this formula, the phase ...

a simple and sensitive method has been developed for the preconcentration and determination of trace level of co(ii) using uv-vis spectrophotometry. β-cyclodextrin polymer modified with 1-(2-pyridylazo)-2-naphthol (pan) is used for the preconcentration of co(ii) from samples at ph 8.5. the polymer is synthesized and characterized using elemental analysis, ft-ir and sem analysis. the factors aff...

titanium nitride-copper (tin-cu) nanocomposite films were deposited onto stainless steel substrate using hollow cathode discharge ion plating technique. the influence of cu content in the range of 2-7 at.% on the microstructure, morphology and mechanical properties of deposited films were investigated. structural properties of the films were studied by x-ray diffraction pattern. topography of t...

background: the aim of this study, we have compared the advantages of oral dydrogestrone with vaginal progesterone (cyclogest) for luteal support in intrauterine insemination (iui) cycles. progesterone supplementation is the first line treatment when luteal phase deficiency (lpd) can reasonably be assumed. objective: this study was conduct to compare the effect of oral dydrogestrone with vagina...

A new type of single-phase stand-alone induction generator using a three-phase induction machine and a single-phase voltage-source PWM inverter is introduced. The generator scheme is capable of producing constant load frequency with a very well regulated output voltage. A small lead acid battery and a single-phase full diode-bridge rectifier are used to feed the inverter. The inverter feeds one...