In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: Strontium ranelate reduces fracture risk in postmenopausal women with osteoporosis. Evidence from non-clinical studies and analyses of bone markers in phase III trials indicate that this is due to an increase in osteoblast formation and a decrease of osteoclastic resorption. The aim of this work was to investigate, in human cells, the mechanisms by which strontium ranelate is able to influence the activities of osteoblasts and osteoclasts.', 'Human primary osteoblasts were used to examine effects of strontium ranelate on replication (thymidine incorporation), differentiation (Runx2 and alkaline phosphatase) and cell survival (cell counts and caspase activity). Osteoprotegerin (OPG) was measured by quantitative reverse transcription PCR (qRT-PCR) and elisa and receptor activator of NFkappaB ligand (RANKL) by qRT-PCR and Western blot. As strontium ranelate has been proposed as an agonist of the calcium-sensing receptor (CaSR), the involvement of CaSR in the effects of strontium ranelate on OPG and RANKL expression, and cell replication was examined using siRNA.', 'Strontium ranelate increased mRNA and protein levels of OPG and suppressed those of RANKL. Strontium ranelate also stimulated osteoblast replication and differentiation and increased cell survival under stress. Knocking down CaSR suppressed strontium ranelate-induced stimulation of OPG mRNA, reduction of RANKL mRNA, and increase in replication, indicating the involvement of CaSR in these responses.\Question: Do osteoblasts play key roles in the mechanisms of action of strontium ranelate?
Our results demonstrate that osteoblasts play a key role in the mechanism of action of the anti-fracture agent, strontium ranelate by mediating both its anabolic and anti-resorptive actions, at least in part, via activation of CaSR.

Context: To investigate whether intracavitary physiotherapy is superior to endometrial scratching in patients with recurrent implantation failure (RIF) after in vitro fertilization/intracytoplasmic sperm injection- embryo transfer (IVF/ICSI-ET) cycles.', 'According to the inclusion criteria defined by our hospital, 63 patients with RIF were included in the retrospective study. 20 patients who received intracavitary physiotherapy were classified into Group A, 8 patients with both intracavitary physiotherapy and endometrial scratching were into Group B, and 35 patients who underwent endometrial scratching were into Group C. The primary outcome measures were implantation and clinical pregnancy rates. The secondary outcome measure was pregnancy outcome.', 'There were no statistical differences in implantation and clinical pregnancy rates between Groups A and C (29.41 vs 35.59 %, 45.00 vs 48.57 % respectively, P > 0.05), Groups B and C (36.36 vs 35.59 %, 50.00 vs 48.57 % respectively, P > 0.05). In addition, no statistical differences were discovered in pregnancy outcomes between Groups A and C (P > 0.05), Groups B and C (P > 0.05).\Question: Is intracavitary physiotherapy inferior to endometrial scratching in patients with recurrent implantation failure?
Intracavitary physiotherapy is not inferior to endometrial scratching on improving implantation and clinical pregnancy rates in patients with RIF after IVF/ICSI cycles.

Context: Administration of sc morphine has been recommended two hours after the end of iv morphine titration in the postanesthesia care unit (PACU), but in some cases patients complain of pain earlier than this. We assessed pain after the end of iv morphine titration and studied the characteristics of patients who needed rescue sc morphine.', 'Postoperative pain was assessed using the visual analogue scale (VAS; 0 to 100) and the threshold required to administer morphine in the PACU was a score of 30. VAS was measured every 15 min up to two hours after the end of iv morphine titration. Patients were divided into two groups, those who required sc morphine before two hours and those who did not. Data are expressed as mean +/- SD or odds ratio (OR; 95% confidence interval).', 'Four hundred and two patients were analyzed. Mean age was 51 +/- 19 yr, initial VAS 69 +/- 19, and the dose of iv morphine 11.7 +/- 6.6 mg. The number of patients requiring sc morphine within two hours was 84 (21%). These patients had more severe initial postoperative pain (73 +/- 20 vs 68 +/- 19, P < 0.05), and experienced sedation more frequently during morphine titration (45 vs 25%, P < 0.001). Using a multivariate analysis, occurrence of sedation during titration [OR 2.3 (1.4-3.8), P < 0.001] and an initial pain score > or = 60 [OR 1.9 (1.0-3.4), P < 0.05] were significantly associated with the need for rescue sc morphine.\Question: Are a high initial VAS score and sedation after iv morphine titration associated with the need for rescue analgesia?

Sedation during titration and an initial VAS > or = 60 are characteristics of the patients who require rescue (less than two hours) sc morphine after iv morphine titration.