Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral views of the chest are provided . The patient was positioned upright . The lungs are mostly clear , though there may be mild left basal atelectasis . No clear signs of pneumonia or CHF . No large effusion or pneumothorax seen . The heart size appears normal . The aorta is unfolded with atherosclerotic calcifications along the wall of the thoracic aorta . Bony structures are intact .
    OUTPUT:
    
No signs of pneumonia .