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1.
目的 探讨医学本科生气质性乐观与抑郁体验、生活满意度的关系,为改善医学生的心理健康提供依据.方法 方便抽取某医学院校在校本科生300名,采用生活取向测量问卷(LOT)、抑郁体验问卷(DEQ)、生活满意度问卷(SWLS)进行调查.结果 男女医学生乐观水平差异无统计学意义(P>0.05),独生子女乐观水平显著高于非独生子女,差异有统计学意义(P<0.01);乐观维度和生活满意度显著正相关(r=0.40,P<0.01),悲观维度与无助性抑郁和内射性抑郁维度显著正相关(r=0.39,0.49,P<0.01);悲观因子显著正向预测抑郁(β=0.491,P<0.01),乐观因子显著正向预测生活满意度(β=0.357,P<0.01).结论 医学生的气质性乐观和抑郁、生活满意度有着密切关系,气质性乐观可能是影响医学生心理健康的重要因素.  相似文献   

2.
目的:探讨甲状腺肿瘤和癌旁正常甲状腺组织中VEGF-C和ERβ的表达与组织平均淋巴管密度的相关性.方法:采用SP免疫组织化学染色检测116例甲状腺癌、56例甲状腺腺瘤和20例正常甲状腺组织中VEGF-C和ERβ及D2-40的表达;以D2-40阳性结果计算组织平均淋巴管密度(LVD).观察不同甲状腺组织中VEGF-C和ERβ的表达水平并分析其与LVD的相关性.结果:甲状腺癌组织中VEGF-C的高表达阳性率显著高于正常甲状腺和甲状腺腺瘤(P<0.05),ERβ的高表达阳性率显著低于正常甲状腺和甲状腺腺瘤(P<0.05);两者表达呈轻度负相关(r=-0.312,P<0.01);甲状腺癌VEGF-C表达与淋巴结转移和TNM分期有关(P<0.01).用D2-40标记的LVD值在甲状腺癌、甲状腺腺瘤和正常甲状腺组织之间有显著性差异(P<0.001).甲状腺癌中淋巴结转移组LVD显著高于无淋巴结转移组(P<0.0001).VEGF-C表达与D2-40呈正相关(r=0.515,P<0.01).结论:ERβ表达下调可能通过促进VEGF-C的表达,进而影响淋巴管增生,促进肿瘤淋巴道转移.  相似文献   

3.
目的 探讨公立医院医务人员职业倦怠对工作满意度及离职倾向的影响。方法 采用问卷调查法进行数据收集,采用多元线性阶层回归分析进行数据分析。结果 情绪衰竭(β= -0.292,P<0.01)和情感疏远(β= -0.300,P<0.01)能显著降低医务人员的工作满意度;情绪衰竭(β= 0.247,P<0.01)和情感疏远(β= 0.173,P<0.01)显著增加了医务人员的离职倾向;成就感低落可以预测医务人员的工作满意度(β= 0.175,P<0.01)。结论 职业倦怠显著降低医务人员工作满意度水平并增加了他们的离职倾向。  相似文献   

4.
Chen L  Liu CJ  Tang M  Li A  Hu XW  Zhou Y  Hescheler J 《生理学报》2006,58(1):14-20
应用全细胞膜片钳技术探讨β-淀粉肽(1-40)(β-amyloid peptide1-40,Aβ1-40)对新鲜分离的大鼠海马CA1区锥体神经元高电压依赖性钙通道电流(high voltage-activated calcium channel current,IHVA)的作用并观察银杏内酯B(ginkgolideB,GB)对该作用的影响.利用细胞外灌流或者电极内液给药的方法,比较加药前后电流幅度的变化以判断药物是否发挥作用.细胞外给予老化处理的Aβ1-40可以浓度依赖性地增强IHVA的幅度,Aβ1-40的浓度为0.01~30 μmol/L时可分别使IHVA幅度增加(5.43±3.01)%(n=8,P>0.05)、(10.49±4.13)%(n=11,P>0.05)、(40.69±8.01)%(n=16,P<0.01)、(58.32±4.85)%(n=12,P<0.01)和(75.45±5.81)%(n=6,P<0.01);新鲜配制的Aβ1-40对IHVA几乎没有影响(n=5,P>0.05).L-型钙通道阻断剂nifedipine可以抵消Aβ1-40对IHVA的增强作用.Aβ1-40(1.0μmol/L)对IHVA的增强作用可以被cAMP的类似物8-Br-cAMP和腺苷酸环化酶(adenylyl cyclase,AC)的激动剂forskolin增强[分别为(66.19±5.74)%,P<0.05和(73.21±6.90)%,P<0.05],被蛋白激酶A(protein kinaseA,PKA)的抑制剂H-89减弱[(20.08±2.18)%,P<0.05].GB可有效地减弱Aβ1-40对IHVA的增强作用.以上结果表明Aβ1-40可通过AC-cAMP-PKA增强IHVA引起胞内钙超载,这可能是其产生神经毒性作用的机制之一.GB可通过抑制Aβ1-40引起的异常钙离子内流对神经元起一定保护作用.  相似文献   

5.
目的 探讨谷氨酰胺与2型糖尿病的关系.方法 采用高效液相色谱仪(HPLC)来测定新疆维、哈两民族血浆中谷氨酰胺的含量;使用放免法测定空腹血清胰岛素(FINS)含量;采用全自动生化分析仪来测定空腹血清中总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDLC)、低密度脂蛋白(LDLC)的含量.结果 维吾尔族正常人与糖尿病患者之间血浆中谷氨酰胺含量差异有统计学意义(P<0.01);哈萨克族正常人与糖尿病患者之间血浆中谷氨酰胺含量差异无统计学意义;维哈两民族的正常人血浆中谷氨酰胺含量差异有统计学意义(P<0.01);维哈两民族的糖尿病患者血浆中谷氨酰胺的含量差异有统计学意义(P<0.05).维哈两民族人群血浆中的谷氨酰胺含量与空腹血糖(FBG)水平呈负相关(r=-0.4858,P<0.001),与FINS水平呈正相关(r =0.236,P<0.05),与胰岛素分泌指数(HOMA-IS)呈正相关(r=0.52,P=0.001),与TG呈负相关(r=-0.4330,P<0.01),与LDLC呈负相关(r=-0.4077,P<0.01),与HDLC呈正相关(r=0.2553,P<0.01).结论 谷氨酰胺可能是2型糖尿病的一个保护性的影响因素.  相似文献   

6.
西南高山地区净生态系统生产力时空动态   总被引:2,自引:6,他引:2  
庞瑞  顾峰雪  张远东  侯振宏  刘世荣 《生态学报》2012,32(24):7844-7856
西南高山地区生态系统类型丰富、地形复杂,是响应全球气候变化的重点区域,对全球气候变化具有重要的指示作用.应用生态系统模型(Carbon Exchange between Vegetation,Soil,and the Atmosphere,CEVSA)模型估算了1954-2010年西南高山地区净生态系统生产力(NEP)的时空变化,分析了其对气候变化的响应.结果表明:(1)1954-2010年西南高山地区NEP平均为29.7gC·m-2·a-1,其中低海拔地区常绿针叶林和常绿阔叶林NEP较高,而高海拔地区的草地覆盖类型NEP较低.(2)西南高山地区NEP总量的变动范围为-8.36-29.4Tg C/a,平均每年吸收碳15.4Tg C;NEP年际下降趋势显著(P<0.05),平均每年减少0.187Tg C,下降显著的区域占研究地区总面积的35.2% (P<0.05),其中草地(-0.526 g C·m-2·a-2,P<0.01)和常绿针叶林(-0.691g C·m-2·a-2,P<0.01)下降趋势极为显著.(3)年NEP总量的年际变化与年平均温度呈负相关(r=-0.454,P<0.01),与年降水量呈正相关(r=0.708,P<0.01),与温度显著负相关的区域占60.3% (P<0.05),与降水显著正相关的区域占52.1%(P<0.05),其中草地和常绿针叶林均与温度极显著负相关(r=-0.603,P<0.01;r=-0.485,P<0.01),而与降水量极显著正相关(r=0.554,P<0.01; r=0.749,P<0.01).(4)西南高山地区是明显的碳汇区,但是由于土壤异养呼吸(HR,heterotrophic respiration)的增长速度大于净初级生产力(NPP,net primary production)的增长速度,最近20a有部分地区开始由碳汇转为碳源.  相似文献   

7.
观察低长因子β1(TGF-β1)表达的影响.体外培养人胚肺成纤维细胞,分常氧和低氧24、48、72 h组,用[3H]-脯氨酸掺入法反映细胞总胶原合成和分泌,ELISA法检测细胞上清液中TGF-β1活化蛋白质含量.低氧24、48、72 h,细胞总胶原合成和分泌分别是常氧组的125.88%和124.74%、183.44%和165.73%、152.55%和172.93%(P<0.01).低氧24、72 h,ADM(10-7mol/L)组细胞胶原合成分泌减少了19.24%和20.76%(P<0.01)、9.57%(P<0.05)和10.98%(P<0.01);低氧48 h,ADM(10-9、10-8、10-7mol/L)组胶原合成分泌分别降低了5.57%(P<0.05)和9.19%(P>0.05)、11.09%(P<0.01)和14.49%(P<0.05)、35.41%(P<0.01)和18.57%(P<0.05).低氧48 h,细胞培养液中TGF-β1上升了24.17%(P<0.05),加入ADM(10-7mol/L),TGF-β1比对照组下降了17.53%(P<0.05);低氧72 h,ADM(10-7mol/L)组TGF-β1下降了19.49%(P<0.05).低氧时ADM通过阻碍成纤维细胞胶原合成而影响低氧性肺血管改建及损伤组织修复过程,ADM与TGF-β1可能通过相互拮抗,共同调节成纤维细胞胶原的生成.  相似文献   

8.
目的:调查研究医学研究生群体的心理健康状况并探索行之有效的心理评估方法。方法:采用卡特尔16种个性因素测验和SCL-90症状自评量表两个测验工具对某医科大学600名硕士研究生进行测试,结合访谈法调查医学研究生心理健康状况。结果:(1)医学研究生16PF测验与原常模进行单样本t检验,结果显示存在显著性差异的有乐群性(t=2.619,P0.01)、聪慧性(t=3.223,P0.01)、稳定性(t=-18.660,P0.001)、恃强性(t=9.23,P0.001)、兴奋性(t=19.732,P0.001)、敢为性(t=11.471,P0.001)、敏感性(t=-8.935,P0.001)、怀疑性(t=-23.101,P0.001)、幻想性(t=3.800,P0.001)、忧虑性(t=10.801,P0.001)、实验性(t=-5.788,P0.001)、独立性(t=-6.814,P0.001)、自律性(t=2.549,P0.01)、紧张性(t=-7.949,P0.001)、适应与焦虑型(t=17.262,P0.001)、内向与外向型(t=14.596,P0.001)、感情用事与安详机警型(t=11.259,P0.001)、心理健康(t=-16.301,P0.001)、专业成就(t=4.182,P0.001)、创造能力(t=-11.600,P0.001)及新环境成长能力(t=-9.882,P0.001)21个因子;而与常模不存在显著性差异的是有恒性、世故性、怯懦与果断型三个因子。效果量检验显示稳定性(d=-1.14)、恃强性(d=0.57)、兴奋性(d=1.3)、敢为性(d=0.75)、敏感性(d=-0.53)、怀疑性(d=-1.41)、幻想性(d=0.21)、忧虑性(d=0.65)、实验性(d=-0.32)、独立性(d=-0.4)、紧张性(d=-0.47)、适应与焦虑型(d=0.99)、内向与外向型(d=0.88)、感情用事与安详机警型(d=0.63)、心理健康(d=-0.91)、专业成就(d=0.23)、创造能力(d=-0.63)及新环境成长能力(d=-0.52)18个因子效果值均大于0.2,而乐群性、聪慧性、自律性效果值d分别为0.16、0.18、0.14,均小于0.2。(2)SCL-90各项指标与国内常模进行单样本t检验,结果显示医学研究生在强迫(t=3.415,P0.001)、抑郁(t=2.776,P0.01)、焦虑(t=3.292,P0.01)、恐怖(t=3.795,P0.001)、偏执(t=2.451,P0.01)与国内常模有显著性差异。效果量检验结果显示强迫(d=0.36)、焦虑(d=0.56)、偏执(d=0.41)3个因子效果值处于(0.2,0.7)之间,而抑郁、恐怖两个因子维度d值分别为0.12、0.17。结论:医学研究生具有良好的个性特点,但心理健康状况不容乐观,应及早提出并实施行之有效的心理干预对策。16PF与SCL-90两者结合使用一定程度上可以提高心理评估的准确性。  相似文献   

9.
采用人工接蜂、桉树组织石蜡切片和生化组分测定等方法研究了桉树受桉树枝瘿姬小蜂诱导后的生理生化响应机制.结果表明:DH201-2叶柄角质层厚度和油囊数量均较GL-UG9的厚、多,且差异均达到极显著水平(P角质层厚度=0.00001 <0.01,P油囊数量=0.00209<0.01),但是GL-UG9叶柄表皮细胞厚度和维管束数量均较DH201-2厚、多,差异分别达到显著水平(P=0.015215<0.05)和极显著水平(P=0.002375<0.01),DH201-2茎皮层薄壁细胞厚度、油囊直径、维管束数量较GL-UG9厚、多,差异分别为显著(P皮层薄壁细胞厚度=0.04071 <0.05)、极显著(P油囊直径=000016<0.05)、极显著(P维管束数量=0.00000<0.01).而GLUG9茎角质层和表皮细胞厚度均较DH201-2厚,差异达到了极显著水平(P角质层厚度=0.00167,P表皮细胞厚度=0.00000<0.01);桉树枝瘿姬小蜂虫瘿为组织瘿,由内到外可以分为:营养组织层、薄/厚壁组织层、维管束层、皮层、表皮等结构;接种桉树枝瘿姬小蜂成虫后,桉树叶片可溶性总糖、游离氨基酸、叶绿素含量均升高,差异达到了极显著水平(P<0.01),但是蛋白质、pH值、类黄酮、总酚的变化没有达到显著水平(P>0.05);吲哚乙酸氧化酶、过氧化物、过氧化氢酶活力均有不同程度的升高.研究显示桉树枝瘿姬小蜂入侵诱导了桉树一系列的生理生化变化,实验结果为抗桉树枝瘿姬小蜂桉树无性系的选育技术体系构建提供了理论基础.  相似文献   

10.
目的:探讨不同疼痛患者的焦虑、抑郁和患病行为的关系,为疼痛患者临床心理诊断及心理干预提供必要的参考依据.方法:采用多中心合作的方式,抽取北京、西安、重庆等10家医疗单位的513例疼痛患者进行门诊问卷调查,采用医院焦虑抑郁量表(HADS)和患病行为问卷(IBQ)分别进行测量,对不同疾病种类疼痛患者焦虑、抑郁症状差异和患病行为的差异进行比较,并对焦虑、抑郁和患病行为各维度进行相关和多元逐步回归分析.结果:(1)不同疾病种类疼痛患者HADS总分差异有显著性(F=3.20,P<0.05),其中焦虑因子得分差异无统计学意义(F=1.28,P>0.05),抑郁因子得分差异有统计学意义(F=4.45,P<0.01),癌症患者得分[(9.67±4.70)分]显著高于其他疾病种类;不同疾病种类疼痛患者IBQ总分差异有显著性(F=5.44,P<0.01),其中负性情绪因子得分(F=3.11,P<0.05)和患病角色因子得分(F=9.28,P<0.01)差异有统计学意义,癌症患者得分最高[分别为(9.50±3.68)分和(8.10±1.82)分],显著高于其他疾病种类,行为反应因子得分差异无统计学意义(F=0.80,P>0.05);(2)负性情绪和行为反应因子均与焦虑和抑郁因子呈显著正相关(rmax=0.517,P<0.01;rmin=0.305,P<0.05),多元逐步回归分析发现:焦虑和抑郁的首要影响因素为行为反应因子(分别为Beta=0.323和Beta=0.368),患病角色在抑郁维度上未进入回归方程.结论:不同疾病种类疼痛患者焦虑、抑郁和患病行为存在差异,患病行为对疼痛患者焦虑及抑郁症状具有正向预测作用.  相似文献   

11.
Plasma insulin-like growth factor (IGF)-I, free IGF-I and -II, IGF-binding protein (IGFBP)-1, -2, and -3 together with IGFBP-3 protease activity were measured in 114 postmenopausal and 39 premenopausal healthy women. For each parameter, the mathematical distribution was characterised, and the normal range for pre- and postmenopausal women described, together with correlations to demographic variables and sex-steroids (postmenopausal women).Postmenopausal women had lower levels of plasma IGF-I (P<0.001) and free IGF-I (P<0.001) compared to premenopausal women, while plasma IGFBP-2 (P<0.05) and immunoreactive IGFBP-3 (P<0.001) were higher in postmenopausal women. Free IGF-I (but none of the other parameters) was significantly lower in postmenopausal smokers compared to non-smokers (P<0.05).IGF-I and -II both correlated positively to height (r=0.203, P<0.05 and r=0.198, P<0.05, respectively), while IGF-II correlated positively to weight (r=0.250, P<0.01). Plasma IGF-I correlated positively to androstenedione (r=0.292, P<0.01) and dehydroepiandrosterone sulphate (DHEAS, r=0.202, P<0.05), while a significant positive correlation was observed between IGF-II on the one side and oestradiol (E(2), r=0.227), oestrone sulphate (E(1)S, r=0.238) and androstenedione (r=0.213) on the other side (P<0.05 for all).Our results support a relation between sex-steroids and IGF-I and -II in healthy postmenopausal women. The lower levels of total and free IGF-I in postmenopausal compared to premenopausal women indicate lower bioavailability of this growth factor in elderly females.  相似文献   

12.
Root aeration, arsenic (As) accumulation, and speciation in rice of 20 different genotypes with regular irrigation of water containing 0.4 mg As l(-1) were investigated. Different genotypes had different root anatomy demonstrated by entire root porosity (ranging from 12.43% to 33.21%), which was significantly correlated with radial oxygen loss (ROL) (R=0.64, P<0.01). Arsenic accumulation differed between genotypes, but there were no significant differences between Indica and Japonica subspecies, as well as paddy and upland rice. Total ROL from entire roots was correlated with metal tolerance (expressed as percentage mean of control straw biomass, R=0.69, P<0.01) among the 20 genotypes; total As concentration (R=-0.67, P<0.01) and inorganic As concentration (R=-0.47, P<0.05) in rice grains of different genotypes were negatively correlated with ROL. There were also significant genotype effects in percentage inorganic As (F=15.8, P<0.001) and percentage cacodylic acid (F=22.1, P<0.001), respectively. Root aeration of different genotypes and variation of genotypes on As accumulation and speciation would be useful for selecting genotypes to grow in areas contaminated by As.  相似文献   

13.
The investigation was performed on 113 adolescents in the age between 15 and 18 years (63 boys, 50 girls). Corah Dental Anxiety Scale (CDAS) and Children's Fear Survey Schedule - Dental Subscale (CFSS-DS) were used for evaluation of dental fear and Child Medical Fear Questionnaire (CMFQ) for evaluation of the fear of medical treatment. Achenbach Youth Self Report questionnaire (YSR) was used for evaluation of emotional and behavioral problems. The tests were filled in by children. The aim of the study was to evaluate the level of dental anxiety in adolescents and to assess a cause--consequence relationship between dental anxiety and emotional and behavioral problems in adolescents. The results of CDAS, CFSS-DS and CMFQ tests showed that dental anxiety scores and the total internalizing problems were higher in girls. Girls displayed more physical problems (p < 0.001) and were more prone to anxiety/depression disorders (p < 0.05). Both boys and girls were more aggressive, more prone to delinquent behaviour and had more externalizing problems in comparison with the average values obtained for the Croatian population. Significant correlation coefficients for boys were calculated for age and anxiety/depression, and delinquent behaviour and aggression (p < 0.05). Significant correlations were observed between physical problems and dental anxiety measured by the CFSS-DS test (p < 0.01), and between physical problems and the total internalizing problems (p < 0.05). In girls, the CMFQ scores showed significant correlations between dental anxiety and physical problems (p < 0.05), and anxiety/ depression (p < 0.01) and the total internalizing and externalizing problems (p < 0.05). Significant correlations were calculated for age and the total internalizing and externalizing problems for boys (p < 0.05). According to the results of both CDAS and CMFQ tests, anxiety in girls showed significant correlations with delinquent behaviour (p < 0.01). CDAS scores for girls showed significant correlations with aggression (p < 0.05) and the total externalizing problems (p < 0.01).  相似文献   

14.
目的:测量医学生学习激情现状,探索相关人口学变量差异及影响因素作用机制。方法:通过网络问卷对1793名在校医学生进行问卷调查,回收有效问卷1218份,应用SPSS22.0软件对数据进行统计处理。结果:测量对象的学习激情处于中等偏上水平(4.37±0.91);学习激情平均得分在性别(F=9.097,P<0.05)、生源地(F=14.850,P<0.05)、独生子女情况(F=5.470,P<0.05)方面的差异有统计学意义;成绩水平(β=0.094,P<0.01)、发展规划(β=0.105,P<0.01)、生活满意度(β=0.213,P<0.01)和活力(β=0.253,P<0.01)对医学生学习激情的影响有统计学意义。结论:医学生学习激情水平在性别、生源地、独生与否方面存在显著差异;成绩水平、发展规划、生活满意度、活力是影响医学生学习激情的因素。  相似文献   

15.
INTRODUCTION: The lipid composition of spermatozoa plays an important role for successful fertilization. PATIENTS AND METHODS: In the present study, we analyzed the fatty acid (FA) composition of spermatozoa of normozoospermic, asthenozoospermic, oligozoospermic and oligoasthenozoospermic men. RESULTS: Spermatozoa from asthenozoospermic (P<0.01), oligozoospermic (P<0.05) and oligoasthenozoospermic men (P<0.05) had lower levels of docosahexaenoic acid (22:6w3, DHA) than those from normozoospermic men. In oligozoospermic and asthenozoospermic men, spermatozoa 18:0 content was higher than that of normozoospermics (P<0.01 and P<0.001, respectively). 18:1w9 was higher in oligoasthenozoospermic and oligozoospermic samples when compared with normozoospermic samples (P<0.05 for both). While from the point of view of total w6 FAs there was no significant difference among the groups, the w6/w3 ratio was significantly higher in asthenozoospermic samples than in normozoospermic samples (P<0.05). Monounsaturated fatty acids (MFA) were higher in oligozoospermic samples (P<0.05) than in normozoospermic samples, polyunsaturated fatty acids (PUFA) were lower in asthenozoospermic (P<0.01), oligoasthenozoospermic (P<0.05) and oligozoospermic samples (P<0.05) than in normozoospermic samples. Saturated fatty acids (SFA) were significantly higher in asthenozoospermic (P<0.01) and oligozoospermic samples (P<0.05) compared with normozoospermic samples. In correlation analysis, there were significant positive correlations between DHA with sperm motility (r=0.53), sperm concentration (r=0.36) and normal sperm morphology (r=0.30). In addition, there were significant correlations between PUFA with sperm motility (r=0.50), sperm concentration (r=0.35), and normal sperm morphology (r=0.28), and between w6/w3 with sperm motility (r=-0.47), sperm concentration (r=-0.27), and normal sperm morphology(r=-0.24). DISCUSSION: These suggest that decreased DHA and PUFA, and increased w6/w3 in spermatozoa may be related to infertility in oligo- and/or asthenozoospermic men.  相似文献   

16.
The relationship between placental traits and maternal intrinsic factors of Saanen, German Fawn and Damascus goats was investigated. Data was collected from 93 goats. The results of the study demonstrated that there were positive correlations between placental weight (PW) and cotyledon number (CN) (r=0.498, P<0.01), cotyledon weight (CW) (r=0.880, P<0.01), cotyledon density (CD) (r=0.538, P<0.01), cotyledon width (CWI) (r=0.500, P<0.01) cotyledon length (CL) (r=0.414, P<0.01) and cotyledon density (CD) (r=0.278, P<0.05). CN was negatively correlated with placental efficiency (PE) (r=-0.421, P<0.01) and CD (r=-0.325, P<0.05). While expulsion of placenta, right teat length and cotyledon length were affected by parity of doe (P<0.05) birth weight (BW), CN, right teat diameter (RTD), left teat diameter (LTD), CD, and CL were affected by breed (P<0.01). Breed×parity was found significant both for expulsion time of placenta and left teat length (LTL) (P<0.05). Damascus goats had a significantly longer duration of licking and grooming events than others. Saanen was more likely to require birth assistance compared to the German Fawn.  相似文献   

17.
This study was designed to characterize changes in the motility of the oviductal isthmus in relation to endocrine changes around ovulation in unrestrained sows in their normal environment. Oviductal isthmic motility was monitored on Polyview from 11 h prior to and up to 36 h after ovulation in 13 unrestrained multiparous sows during their second estrus after weaning, using a pressure microtransducer implanted 3 cm into the isthmus. Both the maximum, minimum and mean pressures and the frequency of phasic pressure fluctuations were high prior to ovulation but declined significantly (P<0.05) at 9 to 12 h, 13 to 16 h, 13 to 16 h and 5 to 8 h after ovulation, respectively. Plasma estradiol-17beta and prostaglandin F2alpha metabolite levels declined significantly (P<0.05) at 4 to 7 h prior to ovulation while progesterone levels increased significantly (P<0.01) at 5 to 8 h after ovulation. The decrease in the plasma estradiol-17beta levels was correlated to the decrease in maximum and mean pressures and the frequency of phasic pressure fluctuations (n=113; r=0.30, 0.25, 0.25, respectively; P<0.01) but not to the decrease in minimum pressure (n=113; r=0.17, P>0.05). Similarly, the decrease in PGF2alpha metabolite levels was correlated to the decrease in minimum, maximum and mean pressures and the frequency of phasic pressure fluctuations (n=112; r=0.43, 0.35, 0.38, 0.32, respectively; P<0.001). Conversely, the increase in plasma progesterone levels was correlated to the decrease in minimum, maximum and mean pressures and the frequency of phasic pressure fluctuations (n=113; r=-0.56, -0.70, -0.68, -0.60, respectively; P<0.001). Therefore, the pressure parameters seem to be influenced by changes in the levels of estradiol-17beta, prostaglandin F2alpha and progesterone with respect to ovulation.  相似文献   

18.
Breeding values for feed intake and feed efficiency in beef cattle are generally derived indoors on high-concentrate (HC) diets. Within temperate regions of north-western Europe, however, the majority of a growing beef animal’s lifetime dietary intake comes from grazed grass and grass silage. Using 97 growing beef cattle, the objective of the current study was to assess the repeatability of both feed intake and feed efficiency across 3 successive dietary test periods comprising grass silage plus concentrates (S+C), grazed grass (GRZ) and a HC diet. Individual DM intake (DMI), DMI/kg BW and feed efficiency-related parameters, residual feed intake (RFI) and gain to feed ratio (G : F) were assessed. There was a significant correlation for DMI between the S+C and GRZ periods (r = 0.32; P < 0.01) as well as between the S+C and HC periods (r = 0.41; P < 0.001), whereas there was no association for DMI between the GRZ and HC periods. There was a significant correlation for DMI/kg BW between the S+C and GRZ periods (r = 0.33; P < 0.01) and between the S+C and HC periods (r = 0.40; P < 0.001), but there was no association for the trait between the GRZ and HC periods. There was a significant correlation for RFI between the S+C and GRZ periods (r = 0.25; P < 0.05) as well as between S+C and HC periods (r = 0.25; P < 0.05), whereas there was no association for RFI between the GRZ and HC periods. Gain to feed ratio was not correlated between any of the test periods. A secondary aspect of the study demonstrated that traits recorded in the GRZ period relating to grazing bite rate, the number of daily grazing bouts and ruminating bouts were associated with DMI (r = 0.28 to 0.42; P < 0.05 - 0.001), DMI/kg BW (r = 0.36 to 0.45; P < 0.01 - 0.001) and RFI (r = 0.31 to 0.42; P < 0.05 - 0.001). Additionally, the number of ruminating boli produced per day and per ruminating bout were associated with G : F (r = 0.28 and 0.26, respectively; P < 0.05). Results from this study demonstrate that evaluating animals for both feed intake and feed efficiency indoors on HC diets may not reflect their phenotypic performance when consuming conserved forage-based diets indoors or when grazing pasture.  相似文献   

19.
AIM: To analyze whether bone mineral density (BMD) and bone resorption status are influenced by long-term metabolic control and duration of disease in adolescents with long-standing type 1 diabetes mellitus. METHODS: Twenty-seven adolescents (age 13.1 +/- 1.7 years, duration of diabetes 6.9 +/- 3.0 years) were studied. The BMD, expressed as z score, was measured at the lumbar spine (L1-L4) using dual-energy X-ray absorptiometry, while the urinary excretion of total deoxypiridinoline (Dpyd), a marker of bone resorption, was measured by immunoassay and was corrected by creatinine (Cr). Linear and multivariate correlations between lumbar BMD z score or Dpyd/Cr excretion and age and disease variables [short-term (Hb A(1c latest)) or long-term (Hb A(1c whole duration)) metabolic control, duration, 'diabetes impact index' (mean Hb A(1c whole duration) x duration of disease in months)] were sought. RESULTS: In diabetic subjects the mean BMD z score was -0.44 +/- (SD) 1.02 (95% CI: -0.03; -0.84), and the Dpyd/Cr excretion was not increased. A negative correlation was found between lumbar BMD z score and age (r -0.59; p = 0.001), duration (r -0.39; p = 0.04), and the diabetes impact index (r -0.4; p = 0.04). The Dpyd/Cr ratio correlated negatively with age (r -0.40; p = 0.04) and positively with height velocity (r 0.42; p = 0.04). By using multiple linear regression, age showed a significant inverse correlation with lumbar BMD z score (beta = -0.39; p = 0.0005). A negative correlation was found between lumbar BMD z score and Hb A(1c whole duration) (beta = -0.40; p = 0.02) or diabetes impact index (beta = -0.001; p = 0.01). CONCLUSIONS: Poor metabolic control may expose adolescents with long-standing type 1 diabetes to the risk of developing osteopenia in adult age. Optimization of metabolic control in growing diabetic children may prevent osteoporosis in later life.  相似文献   

20.
南宁市植物群落结构特征与局地小气候效应关系分析   总被引:4,自引:0,他引:4  
着重探讨植物群落结构特征与生态小气候因子间的相关性。结果表明:(1)在林荫处,植物群落总冠幅盖度、总密度、群落重要值均与温度成极显著的负相关;植物群落群落重要值还与相对湿度达到显著正相关。(2)在林隙处,植物群落总平均株高与光照强度成显著正相关,与风速成极显著负相关。(3)植物群落结构特征与其小气候生态效应间的相关性是:总平均株高与遮光效应值达到极显著的正相关,与挡风效应值亦达到显著的正相关。另外,总冠幅盖度与降温效应值成极显著的正相关。同时,总密度与降温效应值亦成极显著的正相关。特别是群落重要值与降温、增湿、挡风、遮光等生态效应值都成显著甚至极显著的正相关。通过分析与探讨南宁市植物群落结构和小气候因子间的相关性机理,可为科学地进行城市绿化、生态城市建设提供理论依据。  相似文献   

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