█ _ Anthony P Hollander Paul V Hatton 2003 حصريا كتاب ❞ Biopolymer Methods in Tissue Engineering Humana Press ❝ 2024 Press: نبذه عن الكتاب: 1 1 Absorbable Poly α Hydroxy Acids Poly (α hydroxyacids) were found to be bioabsorble and biocompatible in the 1960s (1,2) They are the most widely known, studied used bioabsorbable synthetic polymers medicine Polyglycolide (PGA) poly L lactide (PLLA) homopolymers their copolymers (PLGA), as well polylactic acid stereocopolymers produced using , D or DL lactides rasemic polymer copolymer PLDLA all (3) hydroxy acids) can polymerized via condensation, although only low mol wt In order obtain a higher thus mechanical strength longer absorption time, from the cyclic dimers ring opening polymerization appropriate initiators and co The commonly initiator is stannous octoate (2,3) The rate both vitro vivo of hydroxy acids) is dependent on microstructural, macrostructural, environmental factors listed Table degradation mechanism mainly hydrolysis Polylactides (PLAs) absorb bulk erosion—e g erosion occurs simultaneously throughout device Some studies have revealed an autocatalytic PLAs Autocatalysis shows more dense surface layer faster degradation inside samples which has also been reported for PLLA (7), (8), fiber reinforced 70 30 (9), for PDLLA (10), PLA50 (11) Li et al proposed degradation model with faster degrading core slowly shell Biology Books مجاناً PDF اونلاين Biologically Biology natural science that concerned study life, its various forms function, how these organisms interact each other surrounding environment word biology Greek made up two words: bio (βίος) meaning life And loggia ( λογία) means Biology: similarity vegetation animal cover edges African American states, existence same fossil Branches biology Biology ancient thousands years old modern began nineteenth century This multiple branches Among them are: Anatomy Botany Biochemia Biogeography Biofisia Cytology cell science Ecology science Development Embryology embryology Genetics genetics Histology histology Anthropology anthropology Microbiology bacteriology Molecular Biology Physiology functions organs Taxonemia taxonomy Virology virology Zoology zoology