Transcranial Doppler ultrasound was used to determine the natural history of cerebral arterial vascular spasm following severe head injury. Doppler Flow Velocity (DFV) was measured in the anterior cerebral, middle cerebral and terminal carotid arteries. High DFVs consistent with vasospasm were identified in 68% of the 25 patients studied. They came on from between 12 h and 4 days and lasted from 12 h to 14 days. No relationship could be determined between presumed vasospasm and blood pressure, intracranial pressure or outcome. Rises in the maximum DFV value (to above 100 cm s-1) were associated with neurological deterioration in 12 instances (in 11 of these the DFV remained elevated for more than 12 h). Deterioration occurred in three instances without change in DFV. DFV rose to above 100 cm s-1 on 10 occasions without neurological change (but remained elevated for more than 12 h in only four of these). Vasospasm has been found to be more common following head injury and may be a more significant cause of deterioration than previously thought.
Frozen samples from 92 malignant astrocytomas were stained with a panel of monoclonal antibodies directed against macrophages and lymphocytes. A follow-up to death was available on 68 cases which form the basis of this study. Large numbers of macrophages were found in all cases; T lymphocytes, mostly of the CD8 phenotype were also seen in moderate numbers in 70% of cases. CD4-positive cells were present in small numbers in 32% and B cells were seen in only 8% of cases. Analysis of the survival showed no demonstrable correlation between the numbers of macrophages or CD4 lymphocytes and survival. The survival curves for parenchymal CD8 infiltration diverged after 9 months suggesting increased survival for those patients without such an infiltration but the difference failed to reach statistical significance (P = 0.37). No correlation between lymphocytic cuffing and survival was seen after studying all paraffin-embedded material. We conclude that there is no significant statistical correlation between survival and the various types of mononuclear cell infiltrating malignant astrocytomas.
The sheep parotid is a compound tubular gland; its ultrastructure reflects the function of this gland to secrete large amounts of fluid with very little protein. The cells of the secretory tubules possess extensively folded lateral plasma membranes and a fairly large number of mitochondria. Rapid equilibration of water across the epithelium is assured by the close proximity over large areas of intercellular spaces and the wide secretion canaliculi. Numerous long microvilli extend into the latter. Although secretion granules may be quite numerous, there is evidence that many of these granules are not discharged but undergo degradation by lysosomal enzymes. The intercalated ducts are often dilated but excessive distension is probably prevented by bundles of microfilaments in their epithelial cells.
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