How many {symptoms} are to/by {necrosis} ?
What're effects of necrosis?
What are the symptoms of necrosis?
SELECT ( COUNT ( ?c ) AS ?y ) { ?c property:symptoms resource:necrosis }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P780> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q178069 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P780 wd:Q178069 }
33