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

Ex Input:
Abstract: To investigate whether IgG antinuclear antibodies have cross-reactive rheumatoid factor activity, monoclonal IgG antibodies to DNA and Sm from autoimmune MRL-lpr/lpr mice were assayed by ELISA for binding to IgG antigens. Of the nine anti-DNA and anti-Sm monoclonals tested, six showed significant binding to affinity-purified rabbit IgG (RIgG) and human IgG (HIgG). To confirm that cross-reactivities were due to a single antibody, immunoabsorption of a representative polyspecific monoclonal termed C11 (anti-DNA, anti-Sm) on either Sepharose-DNA or Sepharose-RIgG resulted in marked loss of activity to the three antigens DNA, Sm and RIgG compared with immunoabsorption on Sepharose-bovine serum albumin. The monomolecular nature of the cross-reacting antibody was also suggested by inhibition analysis of C11; DNA inhibited C11 binding to RIgG 64%, whereas Sm inhibited binding to RIgG 33%. Aggregated RIgG and HIgG, however, did not inhibit binding of C11 to DNA, Sm, or solid-phase RIgG, probably reflecting the low affinity of this antibody for fluid phase Ig. Together, these findings suggest that antinuclear autoantibodies of the IgG, as well as the IgM, class have polyspecific IgG binding activity and suggest that IgG antinuclear antibodies may emerge from rheumatoid factor responses.

Ex Output:
IgG antinuclear antibodies with cross-reactive rheumatoid factor activity.

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Abstract: Atrial pacing was performed in 16 patients with angina at rest and significant coronary artery stenosis (greater than 70%) over 2 consecutive days in the morning (10 A.M. to 1 P.M.), in the afternoon (4 to 7 P.M.), and at night (12 midnight to 3 A.M.) to assess possible circadian variations of their ischemic threshold. Overall, the incidence of resting angina was highest at night. All pacing results were positive (greater than or equal to 1.0 mm ST segment shift) and tended to be reproducible in nine patients, whereas some or all were negative in seven. Among all positive results, ischemic thresholds at night were significantly lower than those in the morning and in the afternoon (125 +/- 3 vs 138 +/- 3 and 139 +/- 2 beats/min, mean +/- SEM; p less than .005). In nine patients, 19 pacing tests produced ST segment elevation, of which 13 were performed at night (68%). We conclude that patients with resting angina and severe coronary stenosis often exhibit a nocturnal decline in their ischemic threshold, which seems to facilitate development of transmural ischemia during atrial pacing.

Ex Output:
Resting angina with fixed coronary artery stenosis: nocturnal decline in ischemic threshold.

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Abstract: Ex vivo renal artery surgery has been reported by several investigators and has extended the role of revascularization in the treatment of lesions previously managed by nephrectomy alone. Several techniques are available for use, and selection of the most appropriate method can be tailored to the specific anatomy being managed. Our total experience included 27 kidneys that have been managed by ex vivo renal artery reconstruction. Lesions managed in this manner include two kidneys with renal artery stenosis and renal tumors, one kidney with a congenital branch arteriovenous malformation, and 24 kidneys with branch occlusive or aneurysmal disease from fibromuscular dysplasia. Postoperative angiography was performed in 22 cases and defined successful revascularization without technical error in 20 cases. One operative death occurred as a result of myocardial infarction. One patient required reoperation to control bleeding, and two patients had temporary acute tubular necrosis during the postoperative period. Techniques employed included ex vivo repair with autotransplantation to the iliac system (six kidneys), mobilization and perfusion without transection of the renal vein (10 kidneys), and ex vivo perfusion and repair with replacement into the original renal fossa (11 kidneys). The authors believe this latter technique of reconstruction to be preferable to autotransplantation for the usual patient undergoing ex vivo repair of complex renovascular lesions.

Ex Output:
Ex vivo renal artery reconstructions: indications and techniques.