Holding unprotected "materially false and misleading" statement that hospital was " ‘jeopardizing the health of mothers and babies’ by depleting its staff of labor and delivery [nurses], reducing the effectiveness of the remaining [nurses] by increasing their duties, and providing less qualified replacements"
Sustaining the Board's finding that the employer's rule broadly prohibiting wage discussions was an unfair labor practice under § 8, reasoning that "wage discussions can be protected activity and that an employer's unqualified rule barring such discussions has the tendency to inhibit such activity"