Given a passage classify if the passage has a definite objective/aim/goal or not. Output '1' if the passage has a defininte objective/aim/goal and output '0' if the passage does not have a definite objective/aim/goal.

The present study was designed to investigate whether H2S can protect testicular germ cells against heat exposure induced injury and the underlying mechanisms.', 'It was found that all three H2S generating enzymes, cystathionine β-synthase (CBS), cystathionine γ-lysase (CSE), and 3-mercaptopyruvate sulfurtransferase (3 MST), were expressed in mouse testicular tissue. Three episodes of heat exposure (42 °C, 30 min/day, 3 days) significantly decreased endogenous H2S production and down-regulated the expression of CBS and CSE in testes. In primary cultured testicular germ cells, exogenous application of NaHS (an H2S donor) attenuated heat stress (42 °C, 30 min) induced cell death and apoptosis. This was mediated by the inhibitory effects of H2S on cytochrome C release and the ratio of the Bax/Bcl-2. NaHS also improved mitochondrial function by decreasing oxygen consumption and increasing ATP production. NaHS treatment also stimulated SOD activity and reduced ROS production.
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To improve prostate cancer (PC) detection accuracy among patients with a prostate-specific antigen (PSA) above 4.0 ng/ml and asymptomatic prostate inflammation.', 'A total of 136 patients with PSA ranging from 4.0 to 50.0 ng/ml with asymptomatic prostatitis were included in the study cohort. All these patients underwent antibacterial therapy for 2 weeks followed by repeat PSA determination and transrectal ultrasound-guided needle prostate biopsy. The PSA, PSAD (PSA density), and f/t PSA (free/total PSA) before and after antibacterial therapy were compared using t-test. The receiver-operating characteristic (ROC) technique was used to evaluate the effectiveness of PSA, PSAD, f/t PSA, and their changes after antibacterial therapy (DeltaPSA, DeltaPSAD, and Deltaf/t PSA) on PC detection.', 'Among the 136 patients, 33 had PC and the other 103 histologically confirmed benign prostatic disease. After antibacterial therapy for 2 weeks, the PSA (mean +/- standard deviation) decreased from 14.0 +/- 7.8 ng/ml to 10.4 +/- 7.7 ng/ml (P < 0.01). The DeltaPSA, DeltaPSAD, and Deltaf/tPSA were -3.60 +/- 4.3 ng/ml, -0.1 +/- 0.1 ng/ml/ml, and -0.1 +/- 0.1 respectively. The areas under ROC curve were 0.29 for PSA, 0.64 for PSAD, and 0.50 for f/t PSA. The areas under ROC curve were 0.91 for DeltaPSA, 0.96 for DeltaPSAD, and 0.98 for Deltaf/t PSA. These values were increased significantly when compared with those for the PSA-related parameters before antibacterial therapy (P value, DeltaPSA, DeltaPSAD, and Deltaf/t PSA were <0.01).
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Retrospective cohort study.', 'To compare short-term morbidity for primary and revision posterior lumbar fusions.', 'Revision lumbar fusions are unfortunately relatively common. Previous studies have described an increased risk of postoperative complications after revision lumbar fusion; however, these studies have been limited by small sample sizes, poor data quality, and/or narrow outcome measures. There is a need to validate these findings using a high-quality, national cohort of patients to have an accurate assessment of the relative risk of revision posterior lumbar fusions compared with primary lumbar fusion.', 'The prospectively-collected American College of Surgeons National Surgical Quality Improvement Program database was used to identify patients that underwent undergoing primary and revision posterior lumbar fusion from 2005 to 2013. The occurrence of individual and aggregated postoperative complications within 30 days, along with rates of blood transfusion and readmission, were compared between primary and revision procedures using bivariate and multivariate Poisson regression with robust error variance to control for patient and operative characteristics. Operative time and postoperative length of stay were compared between groups using bivariate and multivariate linear regression.', 'Of the 14,873 posterior lumbar fusion procedures that met inclusion criteria, 1287 (8.7%) were revision cases. There were no differences in the rates of 30-day postoperative complications or readmission between primary and revision posterior lumbar fusion using multivariate analysis to control for patient and operative characteristics. Similarly, no significant differences were found for operative time or postoperative length of stay. There was an increased rate of blood transfusion for revision surgery compared with primary surgery (relative risk 1.4, P\u200a<\u200a0.001).

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