A 40-year-old woman suddenly developed severe headache, occipital pain, and vomiting for 8 hours, without fever. No history of hypertension. Physical exam: conscious, mild hypertension. Right pupil dilated with absent pupillary light reflex, right upper eyelid ptosis, inability to move the eye upward, downward, and inward. Nuchal rigidity, Kernig's sign (+). Brain CT shows hyperdense signals in the interhemispheric fissure, sylvian fissure, and basal cisterns. If cerebrospinal fluid (CSF) examination is performed, which of the following is most likely to be found?