Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.
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Question: Abstract: Neutron Activation Analysis (NAA) was used to investigate trace element patterns in serum, packed cells, and dialysate of CAPD patients. The concentrations of the elements Cs, Cu, Fe, and Mn in serum and packed cells appeared to be maintained within the normal range, while the levels of the non-essential element Br in both serum and packed cells were subnormal. The serum Cr values were extremely high (20 to 50 times higher than the normal serum level). The amount of Cr absorbed from the dialysate was calculated to be ten times higher than the daily dietary uptake. The Co concentrations were normal in packed cells but were significantly increased in serum. The Rb content in packed cells was slightly lower than normal, while the serum value was normal. Se was maintained within the normal range in packed cells, but the serum concentration was slightly lower than normal. The concentrations of Zn were low in serum and appeared to be higher than normal in packed cells. In conclusion, this analysis of the trace element status of CAPD patients reveals two major abnormalities. There is an apparent loss of Br from the blood towards the dialysate and on the other hand, a dramatic accumulation of Cr into the blood as a result of the very high Cr content in the dialysate.

Answer: Trace elements in serum, packed cells, and dialysate of CAPD patients.

Question: Abstract: The influence of various medium supplements on Sertoli cell (Sc) monolayer permeability to [3H]inulin and polarized secretion of transferrin (Trf) and androgen-binding protein (ABP) was investigated in a two-compartment culture chamber. Sc from 14- and 18-day-old rats were maintained for 13 days in one of the following media: Modified Eagle's Medium-Ham's F-12 (DFM), DFM plus insulin, epidermal growth factor, progesterone, hydrocortisone, and vitamins A and E (6F), 6F plus testosterone (7F), 7F plus FSH (8F), 6F plus 2% fetal bovine serum (6F2S), 6F plus 5% fetal bovine serum (6F5S). The monolayer permeability to [3H]inulin decreased rapidly during the initial 3-5 days of culture for the Sc isolated from 18- and 14-day old animals, then remained stable in all media except DFM. Morphological examination revealed the presence of tight junctions between neighbouring Sc in both age groups, indicating their de novo formation. Secretion of Trf was lowest in DFM and steadily declined. In all other media, Trf secretion peaked on day 5 and remained relatively constant after day 7. Medium 7F only slightly and inconsistently increased the secretion, whereas 8F was always highly stimulatory compared to 6F. Supplementation of 6F with serum resulted in the greatest Trf secretion. In the case of ABP, three different secretion patterns were noted depending on the medium composition; secretion was greatest in the presence of 5% fetal bovine serum. The medium supplements also differentially affected the polarity of Trf and ABP secretion. The ratio of Trf secreted to the outer and inner compartments (OC/IC) was approximately 2.0 in DFM and was not influenced by supplements in 6F, 7F, and 8F. However, in serum-containing media, the OC/IC ratio gradually increased with time to about 5.0 on day 13. The average OC/IC ratio of ABP was 1.7 in DFM and, in contrast to Trf, declined to 0.7 in other serum-free media. Serum supplementation reversed and increased the ABP ratio to about 6.0 on day 13. These data indicate that Sc grown on permeable supports form confluent monolayers that limit the diffusion of macromolecules, most likely due to the formation of tight junctions. The monolayer permeability as well as the total and polarized secretion of Trf and ABP are differentially regulated by hormones and serum factors.

Answer: Bipolar secretion of androgen-binding protein and transferrin by Sertoli cells cultured in a two-compartment culture chamber.

Question: Abstract: To determine the relative contributions of the atrial and ventricular septa to total cardiac septation in patients with atrioventricular (AV) canal defect, two-dimensional echocardiography was used to measure the length of each portion of the septum in 14 patients with partial AV canal and 13 patients with the complete form of this lesion. Results were compared with similar data from 30 normal children, 10 patients with dilated cardiomyopathy and 11 patients with ostium secundum atrial septal defect. In patients with partial AV canal, the portion of total cardiac length occupied by the atrial septum did not differ from normal (24.8 +/- 9.9% versus 28.7 +/- 7.9%, p greater than 0.05), but there was a deficiency of both AV and ventricular septal tissue, the latter occupying only 48.2 +/- 7.0% of total cardiac length (versus 57.9 +/- 4.1% in normal subjects, p less than 0.05). Similarly, patients with complete AV canal had a normal amount of atrial septal tissue, a deficiency of AV septal tissue and a deficiency of ventricular septal tissue which was even greater than that of patients with a partial defect (39.4 +/- 5.0% versus 48.2 +/- 7.0%, p less than 0.05). Thus, although partial AV canal defect is often called ostium primum atrial septal defect, the amount of atrial tissue is usually normal, the defect being formed by a deficiency of AV and ventricular septal tissue. In the complete form of the lesion, the deficiency of ventricular septal tissue is greater.

Answer:
Cardiac septation in atrioventricular canal defect.