الفهرس 
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Abstract
Antimicrobial resistance is a natural phenomenon that is exacerbated by the use of antimicrobial drugs. Due to the natural phenomenon of antimicrobial resistance and improper use of available antimicrobial treatments, antibiotic resistance has now become a global problem. It is currently known that about 40-80% of bacterial cells on Earth are capable of forming biofilms . In many cases, biofilm growth has been harmful. For example, in medical facilities, biofilms have also been shown to remain on the surfaces of medical devices and on patient tissues causing persistent infections . Biofilms are a community of bacteria that attach to a surface and are held together by a self-produced polymer matrix composed mostly of polysaccharides, proteins secreted by the bacteria, and extracellular DNA.
Biofilms, so named because they resemble a thin film under a microscope, have a distinctive structure consisting of tower-like shapes and small mushroom-shaped colonies wrapped in a moist matrix. The formation of bacterial biofilms often depends on the interaction of bacterial cells, substrates and the surrounding medium . The formation of bacterial biofilms is a multi-step process that begins with reversible attachment to surfaces with the help of intermolecular and hydrophobic forces, then progresses to the production of extracellular polymeric substances that enable cells to adhere permanently to the surface .There are five main stages in the process of biofilm formation. : Reversible binding, irreversible binding, production of extracellular polymeric substances, biofilm maturation, and dispersal/detachment
100 random isolates were collected from different clinical samples, fifty from the Hayat laboratory, the doctor’s laboratory, and Tabarak’s laboratory, using sterile bags made of plastic, and transported quickly under sterile conditions. Samples were evaluated in Tabarak’s laboratory.Nutrient agar from the Indian company Hemidia was used to isolate colonies. All inoculation plates were incubated for 24-48 hours at (35+2°C), after which potentially pure colonies were evaluated microscopically, morphologically and biochemical tests . After that, he isolated the pure colonies and made a bacterial suspension from the pure isolates and compared it with the standard 0.5 McFarland suspension.
On this study, 50 urine and throat swab samples were analysed bacteriologically to determine the prevalence of pathogenic Staphylococcus aures (54%), Staph.epidermis(18%), Streptococcus pneumoniae (12%), and Enterococcus faecalis (8%). Following isolate identification; all isolates were inoculated in polystyrene test tubes with TSB media and incubated at 37°C for 24 hours to allow biofilm formation. It was wanted to know if clinical isolates in Damietta governorate had the ability to form biofilms, if they had an antibiotic susceptibility pattern, and if they have the clpC related gene. All 50 gram-positive isolates subjected to biofilm development were biofilm formers using the Tube method (TM). This was consistent with many earlier researches .In this study, the biofilm-forming isolates were most resistant to Cefazolin (82%), Clindamycin-2 (78%), Ceftazidime (76%), and Ampicillin/sulbactam (74%). Vancomycin (64%), Trimethoprim/Sulphamethoxazole (62%) Cefepime (60%), Erythromycin (58%), Cefuroxime (54%), Amoxicillin (50%), Tetracycline (34%), Linezolide (28%), Azithromycin (22%), Norfloxacin (22%) Gatifloxacin (16%), Tobramycin (12%), Doxycycline (8%), Chloramphenicol (4%) and Meropenem (2%).