Sharif Digital Repository

Cancer diagnosis area has recently been in the limelight of the medical research and there exist an unremitting focus on the devices & technologies which enable cancer detection in its victims. Lately a genius diagnostic method based on isolation and entrapment of circulating tumor cells has been developed which pave the path for cancer identification. These circulating cells which are detached from the primary tumor are carried out through body by means of circulation system. They play key role in phenomenon called metastasis. Separating these rare cells from multifarious background blood cells, assessing their quantity can supply valuable information on the stage of disease as well as its... 

As the first barrier in front of external damages, skin is prone to the largest number of damages applied to one’s body. Acute wounds are considerably prevalent world-widely, imposing very high costs to governments. The purpose of the current project, is to propose a novel skin scaffold capable of growth factor delivery for enhancing the wound healing process in acute wounds. Such a scaffold should be able to decrease the required time for healing process, also to improve the quality of the regenerated skin compared to available commercial products. Furthermore, it should be highly biocompatible, biodegradable, and non-toxic. In this project, to manufacture the artificial skin scaffold, a... 

Skin tissue as the first protective barrier to the body is always exposed to the most injuries. The purpose of this project is to design an optimum skin scaffold capable of drug delivery for skin wounds healing. To this end, the skin scaffold has been considered as a combination of a hydrogel structure containing polymer microspheres carrying growth factor. Polyvinyl alcohol and sodium alginate polymers were utilized to make the hydrogel substrate. The hydrogel structure was optimized from the viewpoint of the percentage of gelation, water absorption, porosity, mechanical properties, biodegradability, biocompatibility and considering the volume percent of utilized polymers and the... 

In humans, the heart is roughly the size of a large fist and weighs between about 280 to 340 grams in men and 230 to 280 grams in women. Your body has about 5.6 liters of blood. The human heart is an organ that pumps blood throughout the body via the circulatory system, supplying oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. Any damage to the heart, will affect on the other organs. They are four valves within the heart, in which aortic valve is the most important and crucial part of the heart. Calcium sediment on aortic valve leaflets causes reduction in the flexibility of the leaflets, one of the most common heart diseases. In this study, the flexibility... 

Kidney stone disease is one of the diseases that a large number of people experience each year.A Common method for the treatment of kidney stone is the use of acoustic waves, which have attracted the attention of doctors in recent decades. Because of the different structure of kidney stones, the waves transmitted to break these stones are usually performed at different frequencies. Most kidney stones are calcium that can be broken down by using acoustic wave frequencies in the range of 40-20 KHz. Most available lithotripters for the treatment of percutaneous nephrolithotomy (PCNL) are two types: Pneumatic and piezoelectric lithotripters. The lithotripter in this thesis is a piezoelectric... 

Currently, the HIFU (High Intensity Focused Ultrasound) therapy method is known as one of the most advanced surgical techniques in tumor ablation therapy. Simulation of the HIFU therapy in the case of appearance of bon barrier is essential in HIFU planning to improve the usefulness and efficiency of treatment in brain tumor cases. In this work, linear, thermoviscous equations are applied for simulation of phase correction array and steering method, after analysis of performance, these methods are used in a 3D human brain and skull model to estimate thermal ablation in case of using these methods. Results indicate that the maximum focal pressure of 1.42 and 1.65 MPa can be achieved for... 

Particle separation has a variety of applications in biology, chemistry and industry. Among them, circulating tumor cells (CTCs) separation has drawn significant attention to itself due to its high impact on both cancer diagnosis and therapeutics. In recent years, there has been growing interest in using inertial microfluidics to separate micro/nano particles based on their sizes. This technique offers label-free, high throughput, and efficient separation and can be easily fabricated. However, further improvements are needed for potential clinical applications. In this study, a novel inertial separation technique using spiral microchannel with stair-like cross section is introduced. The...