Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
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Question: Abstract: This article stresses the fact that the pediatric patient who presents with back pain is very different from the adult patient with the same complaint. A child is much less likely to complain of symptoms when there is no organic cause for the complaint, and therefore his or her status should be evaluated carefully. When an immediate cause is not obvious, repeated examination should be performed because time may reveal a cause of the symptoms.

Answer: Adult

Question: Abstract: We have previously demonstrated that T3 increases adenylate cyclase activity in rat thymocyte plasma membranes by a mechanism that is calcium dependent. In the present studies we have examined whether calmodulin participates in this response to T3. Initial experiments provided evidence that calmodulin is involved in regulating the activity of the guanyl nucleotide-dependent adenylate cyclase in this tissue. Thus, compared with findings in freshly prepared membranes, dialysis of thymocyte plasma membrane preparations for 20 h at 4 C decreased their calmodulin concentrations from an initial value of approximately 600 ng/100 micrograms protein by about 50% and decreased adenylate cyclase activity by approximately 80%. Although storage of the same preparations under comparable conditions resulted in no change in calmodulin content, it caused an approximate 30% decrease in adenylate cyclase activity. Addition of calmodulin had no effect on adenylate cyclase activity in fresh or stored membrane preparations, but produced a dose-dependent increase in enzyme activity in preparations that had been dialyzed. Further, when added to freshly isolated membranes, three calmodulin antagonists, trifluoperazine, calmidazolium, and calmodulin antibodies, all produced a concentration-dependent inhibition of adenylate cyclase activity, and this was completely reversed in all cases by the addition of high concentrations of exogenous calmodulin. The stimulation of guanyl nucleotide-dependent adenylate cyclase activity that T3 induced in fresh membrane preparations was present in membranes that had been stored, but was absent in those that had been dialyzed. In addition, the response to T3 in fresh membranes was inhibited or abolished by all three calmodulin antagonists. Both in dialyzed membranes and in the presence of antagonists, the response to T3 was restored by the addition of exogenous calmodulin. We conclude that calmodulin influences the activity of the guanyl nucleotide-dependent adenylate cyclase in rat thymocytes and ultimately mediates the stimulation of enzyme activity that T3 produces. Such mediation very likely explains the calcium-dependent nature of the stimulatory effect of T3 on thymocyte adenylate cyclase activity.

Answer: Adenyl Cyclase

Question: Abstract: Papillomas of the respiratory and genital tracts are caused by the same papillomavirus genotypes, and mothers of children with respiratory papillomatosis often have a history of genital warts. Only one of 109 cases reviewed gave a history of birth by cesarean section, whereas ten cesarean deliveries would have been the expected number for this group on the basis of national rates. The single case was delivered by elective cesarean section before the rupture of the membranes, and the child developed respiratory papillomatosis in the first year of life. These findings suggest that in juvenile-onset disease, the transmission of infection from mother to child occurs most often during passage through an infected birth canal, but that intrauterine infection of the fetus is also possible. Papillomavirus infection of the female genital tract is common, but respiratory papillomatosis is rare. On the basis of crude estimates of annual number of children born to infected mothers and of new cases of juvenile-onset disease, the risk of developing disease for a child born to an infected mother was calculated to be one in several hundred exposures.

Answer:
Cesarean Section