Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.

Q: Abstract: The possible role of prostaglandins in mediating large coronary artery vasodilation by nitrates was investigated by quantitative magnification coronary angiography. The effects of aspirin (1 g systemically and 100 mg intracoronary) in preventing large coronary artery vasodilation induced by intracoronary isosorbide dinitrate was investigated in 16 patients. Of these, 5 received 0.3 mg (Group 1A) and 11 received 3 mg (Group 1B) intracoronary isosorbide dinitrate, before and 15 minutes after aspirin. Relative to control, 0.3 mg isosorbide dinitrate induced a 19 +/- 9% (mean +/- SD) (p less than 0.01) and 19.5 +/- 11% (p less than 0.01) increase in coronary diameter before and after aspirin, respectively (p = NS). Changes after 3 mg isosorbide were 23 +/- 12% (p less than 0.01) and 26.5 +/- 14% (p less than 0.01), respectively, before and after aspirin (p = NS). In 10 additional patients (Group 2), the effect of the same dose of aspirin on rest coronary artery tone was assessed: changes relative to control were 0.9 +/- 5.5% (p = NS) minutes after aspirin. The intracoronary administration of 3 mg isosorbide dinitrate produced a 24.7 +/- 11% increase in coronary diameter (p = NS versus pre- and postaspirin isosorbide in Group 1B). Urinary 6-ketoprostaglandin-F1 alpha values in urine samples collected in the 8 hours before and the 8 hours after the study in five patients in Group 1B and five patients of Group 2, revealed a 36 +/- 14% (mean +/- SD) reduction in excretion of prostacyclin (p less than 0.01). These data rule out a role for prostaglandins both in mediating dilation of large coronary arteries by nitrates and in affecting their vascular tone at rest.

A: Coronary vasodilation by nitrates is not mediated by the prostaglandin system: a quantitative cineangiographic study.
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Q: Abstract: To determine if constituents of cotton plants might play a role in byssinosis by injuring pulmonary epithelium, we added extracts of cotton dust, green bract, and field-dried bract to human A549 and rat type II pneumocytes. Injury was measured as pneumocyte lysis and detachment, and inhibition of protein synthesis. Extracts of cotton dust and field-dried bract produced significant dose- and time-dependent lysis and detachment of both target cells, while green bract extract was less damaging. Extracts treated with polyvinylpolypyrrolidone to remove tannins produced significantly less injury. In contrast, purified 5,7,3',4'-tetrahydroxy-flavan 3,4-diol (THF), a tannin in cotton dust and bract, caused substantial cell damage. Field-dried bract extract and THF also produced dose-dependent inhibition of pneumocyte protein synthesis. Endotoxin levels did not correlate with observed injury. THF added to rat tracheal explants caused epithelial disruption and desquamation, whereas endotoxin did not. Instillation of cotton dust and field-dried bract extract in rat lungs produced disruption of bronchial epithelium and smooth muscle constriction, while polyvinylpolypyrrolidone-treated cotton dust extract produced no injury. These findings suggest that extracts of cotton plants are toxic to alveolar, tracheal, and bronchial epithelium and that THF or other tannins may be the responsible agents.

A: Cotton dust-mediated lung epithelial injury.
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Q: Abstract: The evaluation and treatment of injuries of the ulnar collateral ligament of the metacarpophalangeal joint of the thumb remain controversial. In a retrospective study that was done to assess our ability to determine whether displacement of the ligament (a Stener lesion) was present, we reviewed our accumulated experience with patients who had an injury of this ligament who were treated surgically between 1972 and 1984. Since our method of evaluation changed in 1977, we compared the preoperative and operative diagnoses in the twenty patients who were treated surgically from 1972 through 1976 with those in the twenty patients who were so treated from 1977 through 1984. Considering all forty patients who were treated operatively, sixteen (40 per cent) had a typical Stener lesion, and in two others (5 per cent) the ulnar collateral ligament was rolled up on itself and lying beneath the adductor aponeurosis. From 1972 through 1976, stability was tested with the metacarpophalangeal joint in complete extension or in varying amounts of flexion. Of the twenty thumbs that were evaluated by this technique and were treated surgically, 20 per cent had a Stener lesion. From 1977 through 1984, stability was tested with the joint in full flexion because of the findings in anatomical studies that were completed in 1977; the incidence of a Stener lesion in the twenty thumbs that were treated by repair or reattachment of the ligament during this time was 70 per cent.(ABSTRACT TRUNCATED AT 250 WORDS)

A:
Rupture and displacement of the ulnar collateral ligament of the metacarpophalangeal joint of the thumb. Preoperative diagnosis.
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