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991.
目的 探讨环氧化酶2(COX-2)基因启动子区甲基化水平和蛋白表达与胃黏膜病变的关系,并对其相关的影响因素进行研究.方法 以1201例患有不同胃黏膜病变的高危人群为研究对象,采用免疫组织化学方法榆测COX-2表达,用亚硫酸氢钠-变性高效液相色谱(DHPLC)对COX-2启动子甲基化率进行定量分析,采用13C尿素呼气实验(13C-UBT)对幽门螺旋杆菌(H priori)感染状况进行测定.结果 COX-2甲基化率中位数随胃黏膜病变的加重逐渐升高,在浅表性胃炎和慢性萎缩性胃炎(SG/CAG)、肠上皮化生(IM)及不确定性异型增生和异璎增生(Ind DYS/DYS)病变中分别为10.6%、11.8%、13.8%,各病变组之间差异有统计学意义(X2=8.312,P=0.016).分层分析显示,在H pylori感染阴性病例中,COX-2甲基化率仍随病变加重明显升高,在SG/CAG、IM、Ind DYS/DYS病变中其中位数分别为8.8%、10.6%、14.1%(X2=6.629,P=0.036).进一步分析发现,COX-2甲基化率随着COX-2表达强度的增强而降低,由COX-2弱阳性表达的13.3%降至强阳性表达的7.6%(X2=10.400,P=0.015).结论 COX-2启动子甲基化水平与胃黏膜病变程度及H pylori感染状况密切相关,并与COX-2表达强度呈负相关,说明COX-2启动子区异常甲基化可能在胃黏膜病变的演变过程中起重要作用. 相似文献
992.
Ron Langevin PhD Jerald Bain MD 《Sexual abuse : a journal of research and treatment》1992,5(2):99-118
Thirteen diabetic male sex offenders were compared to 13 nondiabetic sex offenders matched on age, education and offense type. A standard battery of tests administered in the assessment of sex offenders was used to compare the two groups. The tests examine sexual history and preference, substance abuse, violence, personality, and neuropsychological impairment. Results showed that diabetics more often than controls complained of impotence and were nonresponders during phallometric testing. Diabetics, as adults, tended to have less sexual experience with adults and more with pubescent females. The two groups did not differ in number of sexual or nonsexual offenses. The diabetics reported more problems controlling their emotions and more often than controls presented in assessment with inappropriate and/or aggressive behavior and poor cooperation. MMPI results showed diabetics to have more overall clinical disturbance than controls including anxiety, health concerns, family problems, authority problems, criminality, confused thinking and ruminating. Diabetics and controls did not differ in reported frequency of violent behavior but the diabetics responded more extremely, given the circumstances. Diabetics tended to show more violence to their own children. The role of diabetes in the relapse cycle model of offending is discussed. 相似文献
993.
V Allen PhD DW Ryan MB FRCA A Murray PhD FIPSM 《International journal of clinical practice》1994,48(3):125-129
SUMMARY Four specialised air mattresses had interface pressure measured under six body sites prone to pressure sores in 10 subjects, supine and sitting. The mattresses were the Clinirest (SSI) and FirstStep (KCI) continuous airflow mattress overlays, and Airwave (Pegasus) and Nimbus (Huntleigh) alternating pressure air mattresses. On the mattress overlays, average supine interface pressures were 2.33 kPa (scapula), 4.15 kPa (elbow), 1.94 kPa (sacrum) and 2.79 kPa (buttock), although they were higher at the occiput (7.97 kPa) and heel (11.7 kPa). The alternating pressure air mattresses had an average minimum interface pressure close to zero for three sites, rising to 4.28 kPa under the heel. Average maximum interface pressures were 8.61 kPa (occiput), 5.21 kPa (scapula), 4.90 (elbow), 4.85 kPa (sacrum), 4.61 kPa (buttock) and 13.2 kPa (heel). No accepted scientific method exists for comparing the two types of mattress. Our data suggest a clinical benefit at the occiput and heel (supine) in using an alternating pressure air mattress and a benefit in using a continuous airflow mattress overlay at other sites. 相似文献
994.
家兔未成熟心肌缺血再灌注肌浆网摄钙功能的初步研究 总被引:5,自引:2,他引:3
目的 :从亚细胞水平研究未成熟心肌缺血 -再灌注损伤中肌浆网 (SarcoplasmicReticulum ,SR)摄钙功能。方法 :36只家兔随机分为 4组 ,进行离体心灌注。组Ⅰ :幼兔 ,单纯灌注 30min ;组Ⅱ :幼兔 ,停搏 6 0min ,再灌注 30min。组Ⅲ、组Ⅳ为成兔 ,处理分别同组Ⅰ、组Ⅱ ,进行对照。测定各组心功能、冠状动脉流出液血气 ,单细胞内游离钙离子浓度 ([Ca2 + ]i) ,肌浆网Ca2 + -ATPase活性 ,肌浆网45Ca2 + 摄取。结果 :缺血 -再灌注后 ,成熟与未成熟心肌均发生钙超载 (P >0 .0 5 )。未成熟心肌肌浆网Ca2 + ATPase活性 ,肌浆网45Ca2 + 摄取恢复率 ,明显高于成熟心肌 (P <0 .0 5 )。结论 :未成熟心肌缺血 -再灌注损伤钙超载机制不同于成熟心肌 ,肌浆网钙摄取功能 ,在钙超载损伤中不起主要作用。 相似文献
995.
目的 了解安徽省X射线诊断受检者体表剂量水平。方法 体表剂量监测按国家标准 ,采用热释光剂量计。结果 胸部摄片受检者的体表剂量最低 ,为 0 .39~ 0 .5 3mGy ,比胸部透视平均体表剂量减少 88.6 6 %。结论 减少或控制透视比例 ,降低受检者群体的体表剂量 ,以减少医疗照射对人体造成的危害。 相似文献
996.
刘兆星 《中国医科大学学报》1992,12(3):167-168
用RSV-iRNA对BALB/C鼠致敏注射,以融合细胞计数法检测致敏鼠血清的抗融合活性。试验结果表明:RSV-iRNA致敏鼠血清能抑制由RSV引起的典型细胞融合病变,且这种活性可因吸附血清特异抗体而消失。 相似文献
997.
Computer-Assisted Instruction Improves Clinical Reasoning Skills of Dietetics Students 总被引:1,自引:0,他引:1
MARTHA A. RAIDL PhD RD OLIVIA BENNETT WOOD MPH RD JAMES D. LEHMAN PhD WILLIAM D. EVERS PhD RD 《Journal of the American Dietetic Association》1995,95(8)
Objective The effects of a computer-assisted instruction (CAI) tutorial program on learning clinical reasoning skills were compared in undergraduate dietetics students.Design A drill-and-practice program to control for time on task, a tutorial program, and a simulation program, as the test vehicle, were developed. The tutorial and simulation programs presented data on a patient with cardiovascular disease.Setting Subjects were tested in 30 undergraduate dietetics programs.Subjects Participants were 413 undergraduate diet therapy students enrolled in a coordinated program in dietetics (CPD) or a didactic program in dietetics (DPD).Intervention After completion of lectures on cardiovascular disease, subjects were given the drill-and-practice program plus a simulation test (group 1), the tutorial plus a simulation test (group 2), or the simulation test only (group 3).Main outcome measures Scores on the simulation test were compared. Variables included type of CAI, dietetics program, year in school, computer experience, and experience using a medical chart. Mastery of objectives related to lower- and higher-level clinical reasoning skills introduced in the tutorial program was compared.Statistical analysis One-way analysis of variance and Student-Newman Keuls tests were conducted to determine any differences among the three groups. Reliability was determined using the Kuder-Richardson Formula 20.Results The reliability coefficient of the simulation test was 0.93. Group 2 scored higher on the simulation test than group 1 or group 3. As a group, the CPD students scored higher than the DPD students. When CPD and DPD students were divided into the three experimental groups, there was no significant difference between the CPD and DPD student simulation scores. Group 2 mastered all objectives for lower-level reasoning skills and the higher-level decision-making objective better than groups 1 and 3.Applications/conclusions A computer tutorial program enhanced clinical reasoning skills in undergraduate dietetics students. This type of program could be used to supplement many topics taught in diet therapy and provide DPD students with experiential learning before their clinical intern practicums. J Am Diet Assoc. 1995; 95:868–873. 相似文献
998.
999.
鸡胚股骨无血清培养研究软骨形成和骨形成 总被引:3,自引:0,他引:3
为探讨软骨形成和骨形成的作用机制,用孵化14天鸡胚股骨进行无血清培养,对其细胞增殖分化和基质矿化情况进行观察。结果显示:股骨在培养期间长度增长,骺端增大。软骨细胞、成骨细胞增殖分化成熟;成骨细胞分泌基质小泡和类骨质,并有奶盐沉积。提示鸡胚股骨在无血清培养条件下,可在体外进行软骨形成和骨形成,此模型可用来进行骨形成研究。 相似文献
1000.
Tension neck and evaluation of a physical training course among office workers in a bank corporation 总被引:1,自引:0,他引:1
Margita Klemetti RN MSc Nina Santavirta MSc Anneli Sarvimäki RN PhD Hjördis Björvell RN PhD 《Journal of advanced nursing》1997,26(5):962-967
The purpose of this study was to investigate the effects of a physical training course in a group of patients (n=74) suffering from chronic tension neck. All participants in the course were employed by a bank corporation in Helsinki, Finland. A comparable control group (n=77) consisted of office workers with tension neck from the same bank corporation who did not attend any training course. The outcome was analysed 6 months after the course. Pain and disability in the neck and shoulder region did not vary significantly between the group which participated in the training course and the control group. The experimental group had increased the amount of physical workout compared to the control group (83.7% vs 69.0%, P = 0.0448). Also, regarding the frequency of relaxation and stretching exercises the two groups differed significantly: the experimental group had continued to perform exercises more often (P= 0.0434). The frequency of sick leave days did not significantly differ between the groups, but the office workers in the experimental group had more periods of extended sick leave (> 10 days) and the controls had more frequent short sick leaves. The experimental group did increase their physical workout significantly compared with the controls, but no differences were detected regarding pain and disability. In order to gain more benefit more attention should be paid to the educational part of the training courses in order to enhance the patients'self-care abilities. Also, strategies to alleviate psychosocial problems and organized relaxation exercises could decrease muscle tension in the neck in office workers. 相似文献