ABSTRACT
Under mechanical stress, the hexaarylbiimidazole (HABI) motif can cleave to triphenylimidazolyl radicals when incorporated into a polymer matrix. The mechanically produced coloured radicals can initiate secondary radical reactions yielding polymer networks. Thus, the HABI mechanophore combines optical reporting of bond scission and reinforcement of polymers in a single molecular moiety.
ABSTRACT
The records of 44 patients who underwent internal fixation for metastatic fractures between 1970 and 1989 were studied. Excluded were pathologic fractures involving the spine, pelvis, ribs and clavicles. None of the patients was still alive at the time of the study.
Subject(s)
Fracture Fixation, Internal , Fractures, Spontaneous/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Bone Neoplasms/complications , Bone Neoplasms/mortality , Bone Neoplasms/secondary , Bone Plates , Child , Female , Fracture Fixation, Internal/instrumentation , Fracture Fixation, Intramedullary , Fractures, Spontaneous/mortality , Humans , Male , Middle Aged , Retrospective StudiesABSTRACT
Congenital dysphasia is a developmental speech disorder not explained by deafness, phonation disorder, mental retardation, neurologic lesion, or psychiatric disease. The existence of brain lesions has often been postulated but conventional investigations fail to demonstrate any cerebral abnormality. By means of [99mTc]hexamethyl-propyleneamine oxime (HM-PAO) brain single photon emission computed tomography (SPECT) we have studied 14 children suffering from congenital dysphasia. The brain computed tomographic scan was normal in all cases. In two patients with expression impairment the SPECT study demonstrated a hypoperfusion in the inferior frontal convolution of the left hemisphere, involving the Broca's area. In nine of 12 patients with global dysphasia (deficits in both comprehension and expression), SPECT study showed two hypoperfused areas: an abnormality in the left temporoparietal region and a hypoactivity in the upper and middle areas of the right frontal lobe. These results suggest that congenital dysphasia could be due, like acquired aphasia, to specific impairment of the language cerebral areas and that brain SPECT studies with [99mTc]HM-PAO could be useful for a better comprehension of the physiopathology of these disorders.
