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31.
目的:探索学习投入、专业承诺对农村订单定向医学生核心能力的影响,为提升基层卫生人才队伍的质量提供理论参考。方法:通过多阶段整群抽样方法,抽取S省两所医学院校的520名农村订单定向医学生作为研究对象进行调查。采用分层回归法分析学习投入对农村订单定向医学生核心能力的影响,简单斜率检验分析专业承诺对前述两者关系的调节效应。结果:S省农村订单定向医学生核心能力总体平均得分为(3.39±0.549);学习投入对农村订单定向医学生核心能力存在显著正向影响(β=0.358),且专业承诺对前述两者关系存在调节效应,该调节效应使得学习投入对核心能力的影响变强(β=0.206)。结论:完善农村订单定向医学生培养政策,严把录取质量,加大基层基地的建设与投入,重视学生职业素质教育,提升核心能力。  相似文献   
32.
Ochratoxin A (OTA), a naturally occurring mycotoxin, is nephrotoxic in all animal species tested and is considered a potent renal carcinogen, particularly in male rats. Its mechanism of toxicity is still unknown, although oxidative stress appears to be a plausible mechanism. Therefore, the objective of this study was to identify the biological pathways that are modulated in vivo by OTA in male F344 rats in order to gain further insight into its mechanism of renal toxicity. Rats were gavaged daily with OTA (500 microg/kg bw) and gene expression profiles in target and non-target organs were analyzed after 7 and 21 days administration. As was expected, a time-dependent increase of OTA concentrations was found in plasma, kidney and liver, with the concentrations found in both tissues being quite similar. However, histopathological examinations only revealed changes in kidney; signs of nephrotoxicity involving single cell necrosis and karyomegalic nuclei were observed in the treated rats. The number of differentially expressed genes in kidney was much higher than in liver (541 versus 11 at both time points). Several similarities were observed with other in vivo gene expression data. However, great differences were found with previous in vitro gene expression data, with the exception of DNA damage response which was not observed at mRNA level in any of our study conditions. Down-regulation was the predominant effect. Oxidative stress response pathway and genes involved in metabolism and transport were inhibited at both time points. RGN (regucalcin) - a gene implicated in calcium homeostasis - was strongly inhibited at both time points and genes implicated in cell survival and proliferation were up-regulated at day 21. Moreover, translation factors and annexin genes were up-regulated at both time points. Apart from oxidative stress, alterations of the calcium homeostasis and cytoskeleton structure may be present at the first events of OTA toxicity.  相似文献   
33.
目的 探讨成人睡眠呼吸紊乱(sleep breathing disorder,SBD)患者健康相关危险因素,为此类患者的健康管理提供科学依据。方法 对3 000例18岁以上SDB患者进行问卷调查,收集身高、体质量及饮食运动等信息,采用多元逐步Logistic回归分析,探讨该类人群中健康相关危险因素。结果 发放调查问卷3 000份,回收有效问卷2 596份,有效应答率为86.5%。成人SBD患者缺乏体育运动、肥胖、吸烟、饮酒、高盐高脂饮食的比例较高。多因素Logistic回归分析表明,SDB患者在缺乏体育运动的同时,存在吸烟和高盐高脂饮食的相关问题,男性、年龄和高学历是保护因素(P<0.05);肥胖的相关影响因素分别为:男性、年龄、饮酒和高盐高脂饮食,高学历是保护因素(P<0.05);饮酒的相关影响因素分别为:男性、年龄、肥胖、吸烟和高盐高脂饮食(P<0.05);高盐高脂饮食的同时,SDB患者同时存在肥胖、吸烟、饮酒和缺乏体育运动的问题,高学历是保护因素(P<0.05)。结论 应针对成人SBD患者的生活习惯,开展相应的健康教育和行为干预,积极探索该类人群健康管理的卫生模式。  相似文献   
34.
896例成人嗓音声学参数的计算机采集分析   总被引:8,自引:2,他引:6  
目的 通过研究获得有关嗓音医学的数据标准及各种嗓音疾病的特征性客观指标 ,建立嗓音临床检测系统 ,为临床诊断与治疗提供有效的参考标准和方法。方法 应用Dr.Speech(DSS)软件的先进技术 ,按卫生部(司 ) :“语音、语言测试和矫治行业标准”的研究要求 ,采集、分析上海地区成人 5 0 0例正常嗓音以及 396例临床常见嗓音疾病的病理性嗓音的声学样本。结果 正常人的各嗓音声学参数 :基频微扰、振幅微扰、声门噪声、频率颤动、共振峰等值均在DSS软件提供的正常范围内 ,而病理性嗓音声学参数超出该范围 ,并具有各不同的特点。结论 我国成人嗓音声学参数与欧美的相似 ,应用Dr.Speech软件可对各种嗓音疾病进行临床客观检测和评估  相似文献   
35.
Transient-evoked otoacoustic emissions (TEOAEs) were recorded from more than 30000 newborns over a six year period. Analysis was performed on all the TEOAEs that passed the bedside universal hearing screen (n=60431), in order to characterize the normal properties of neonatal TEOAEs and to study ear and sex effects. Short recording times (median=33 s) were observed in combination with high entire TEOAE level (median=18.8 dB SPL for an 81.8 dB SPL peak stimulus), and high reproducibility (median=86%). Signal-to-noise ratio (S/N) of the TEOAE was highly frequency-dependent, being poorer at low frequencies. Prolonged averaging increased median reproducibility to 97%, but the minor S/N-improvement at low frequencies did not justify the longer test time. Highly significant mean lateral asymmetries (right >left) and sex differences (female >male) existed in entire TEOAE level, S/N TEOAE, and in half-octave frequency bands (700–4000 Hz). Mean lateral and sex entire TEOAE level differences were 1.1 dB and 1.3 dB, respectively. Stimulus levels were not affected by ear or sex. Hence, physiological differences at the level of organ of Corti were demonstrated in newborns.  相似文献   
36.
Introduction: Increasing numbers of pre-lingually profoundly deaf adults are seeking a cochlear implant (CI). Pre- and post-operative outcomes are presented on 20 of these patients.

Results: An Adult Pre-Lingually Profoundly Deaf Implant Profile (APDIP) weighted the pre-operative level of concern about potential CI benefit. Results indicated no group mean post-operative open-set improvement. However CUNY sentence testing (auditory plus lip-reading cues) revealed improved performance with a CI. Twelve out of 20 patients used their CIs for more than 10 hours per day, suggesting good usage. Moreover, hours of usage were positively associated with measured benefit on CUNY sentences in the lip-reading plus sound via CI condition. There was no apparent relationship between pre-operative level of concern and post-operative CI performance or hours of processor use.

Conclusion: Results suggest implantation is beneficial and effective in this group.  相似文献   
37.
目的 探讨成年功能性构音障碍患者辅音发音错误的特点,为制定语音训练方案提供依据.方法以42例成年功能性构音障碍患者为研究对象,借助计算机语音工作站对患者进行语音评估,对其辅音的发音错误类型及方式进行分析.结果42例成年功能性构音障碍患者主要的辅音发音错误类型为置换、扭曲,其次为脱落.按发音部位,错误辅音依次为舌尖后音(39例,92.86%)、舌尖前音(31例,73.81%)、舌面音(22例,52.38%)、舌根音(19例,45.24%)、舌尖中音(18例,42.86%)、唇齿音(6例,14.29%)及双唇音(6例,14.29%);辅音错误频率由高至低依次为/sh/、/zh/、/ch/、/r/、/z/、/c/、/s/、/q/、/x/、/j/、/g/、/k/、/h/、/t/、/l/、/d/、/f/、/p/.辅音错误方式有:舌前音化(22例,52.38%)、非送气化(12例,28.57%)、侧化构音(12例,28.57%)、辅音脱落(9例21.42%)、舌后音化(8例,19.05%)、舌面音化(4例,9.52%)、双唇音化(4例,9.52%)、唇齿音化(3例,7.14%).结论成年功能性构音障碍患者的辅音发音错误类型主要是置换和扭曲;错误辅音主要为舌尖后音、舌尖前音、舌面音、舌根音、舌尖中音;辅音发音错误方式主要为舌前音化、非送气化、侧化构音、辅音脱落.  相似文献   
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AIM OF THE STUDY: Contraceptive plants which were introduced by folk in traditional remedies are investigated worldwide. In this study, the contraceptive effects of Ruta graveolens L., which has been mentioned for male contraceptive in Iranian traditional folk medicine, was experimented on human sperm. MATERIALS AND METHODS: Different doses of lyophilized aqueous extract of Ruta graveolens L. were added to an amount of fresh semen, containing 10(6) cells in a 1:1 volumic ratio. Motility and viability of cells, DNA status, mitochondrial activity and sperm revival tests were carried out. RESULTS: The sperm immobilization effects of the extract appeared immediately in a does-dependent manner and 100% of the sperms became immotile at a concentration of 100mg/ml but other parameters were intact. After washing the sperms, motility was returned in 30.8+/-3.2% of the sperms, besides coiled tails in 38.6+/-5.5% of the treated cells, in comparison to 12.5+/-2.0% of the control group (p=0.001). The part of the extract, responsible for immobilization of the sperms was stable upon boiling. CONCLUSIONS: As the cells were alive and immotile, probably some ionic currents are blocked by a thermostable component of the plant which can be promising as a new male channel blocker contraceptive.  相似文献   
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