You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Disease", "Chemical"].

Please return the output as a JSON object of the format: {"Chemical" : ["Naloxone", ...], "Disease" : ["Hypotensive", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Remifentanil pretreatment reduces myoclonus after etomidate. STUDY OBJECTIVE: The aim of the study was to compare the effect of pretreatment with remifentanil 1 microg/kg and the effect of gender on the incidence of myoclonus after anesthesia induction with etomidate. DESIGN: This was a randomized, double-blind study. SETTING: The study was conducted at a university hospital. PATIENTS: Sixty patients were pretreated in a randomized double-blinded fashion with remifentanil 1 microg/kg or placebo. Two minutes after remifentanil or placebo injection, etomidate 0.3 mg/kg was given. MEASUREMENTS: Myoclonus was recorded with a scale of 0 to 3. The grade of sedation (none, mild, moderate, severe), nausea, pruritus, and apnea were recorded after injection of both drugs. MAIN RESULTS: The incidence of myoclonus was significantly lower in the remifentanil group (6.7%) than in the placebo group (70%) (P < 0.001). None of the patients experienced sedation, apnea, nausea, or pruritus after injection of both drugs. In the placebo group, male patients were associated with significantly increased incidence of myoclonus after etomidate administration. CONCLUSION: Pretreatment with remifentanil 1 microg/kg reduced myoclonus after etomidate induction without side effects such as sedation, apnea, nausea, or pruritus. Men experience increased incidence of myoclonus than women after etomidate administration.
{"Chemical": ["remifentanil", "etomidate", "Remifentanil"], "Disease": ["myoclonus", "nausea", "pruritus", "Myoclonus", "apnea"]}