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

[EX Q]: Abstract: Accurate localization of the source of androgen hypersecretion is critical to the appropriate surgical or medical management of women with virilization. Seven patients with virilization and hyperandrogenism of various causes were evaluated with the use of sequential studies: testosterone stimulation and suppression tests; computerized tomography (CT); selective venous catheterization; and 131I-iodomethyl-norcholesterol (NP-59) scintigraphy. Comparison of the diagnostic accuracies of these localization studies with the ultimate diagnoses in this group of virilized women showed that: endocrinologic suppression/stimulation studies are of limited value in tumor localization and helpful only in patients with steroidogenic enzyme deficiencies; both selective catheterization and CT scanning may provide spurious localization data; and NP-59 scintigraphy, by depicting both the anatomic localization and functional androgen hypersecretion, may provide the most significant localization data in the evaluation of patients with virilizing syndromes.
[EX A]: Diagnostic considerations in virilization: iodomethyl-norcholesterol scanning in the localization of androgen secreting tumors.

[EX Q]: Abstract: The incidence of air under the diaphragm in CAPD patients is very low, and causes directly attributable to standard CAPD techniques are even lower. Bowel perforation generally causes a larger volume of air collection under the diaphragm.
[EX A]: Is air under the diaphragm a significant finding in CAPD patients?

[EX Q]: Abstract: Calcium performs a unique role in biology, achieving biological effects through highly specific interactions with and modulation of target proteins. It has been proposed that calcium-modulated proteins possess a characteristic, evolutionarily related, binding fold, known as the EF-hand. The high-resolution X-ray structure of alpha-lactalbumin reveals a Ca2+ binding fold that resembles an EF-hand only superficially and presumably has no evolutionary relationship with it. However, there is clear homology with the corresponding loop in c-type lysozyme (the 'parent' molecule of alpha-lactalbumin). This study, at 1.7 A resolution, represents one of the most accurate analyses of a calcium binding protein yet reported.
[EX A]:
Alpha-lactalbumin possesses a novel calcium binding loop.