AMPK在妊娠期糖尿病发病机制中的作用

腺苷酸活化蛋白激酶是一种重要的蛋白激酶,主要作用是协调代谢和能量平衡.腺苷酸活化蛋白激酶被激活后,在增加骨骼肌对葡萄糖摄取、增强胰岛素敏感性、增加脂肪酸氧化以及调节基因转录等方面发挥重要作用.已经证实脂联素有调节糖脂代谢的作用,但其作用机制尚不十分清楚,很可能是通过腺苷酸活化蛋白激酶介导,对脂联素信号转导通路的研究将成为进一步理解脂联素作用的关键所在.而脂联素又是妊娠期糖尿病的预测因子,所以腺苷酸活化蛋白激酶逐渐成为对妊娠期糖尿病研究中的焦点.     

Interpreting the correlation coefficient when one of the variables is discrete

The effect on the correlation coefficient of discretizing data was investigated in two ways. First, the theoretical effect of dichotomizing data was calculated, and it was shown that the resulting correlation coefficient is considerably less than that between the underlying bivariate normally distributed variables. Second, computer simulations were performed of a model in which a continuous variable (measured with some error) gives rise to a counting variable through a mechanism in which the count is zero below a certain threshold value for the continuous variable and then increases linearly as the continuous variable increases. It was shown that the correlation coefficient between the observed values of the continuous and counting variables decreased as (a) the measurement error increased, (b) the slope of the relationship decreased, and (c) the number of counts decreased. It is concluded that caution is required when interpreting correlation coefficients when one or both of the variables consist of a few (say only four or five) discrete scores.     

Growth factor responsiveness of human retinal pigment epithelial cells

Growth factor effects on DNA synthesis in density-arrested human retinal pigment epithelial cells were assessed by [3H]-thymidine incorporation. Acidic and basic fibroblast growth factor and epidermal growth factor were potent stimulators, whereas platelet-derived growth factor, insulinlike growth factor-1, and insulin were weak or modest stimulators when used alone. When used in combination, each of the above growth factors caused a significant enhancement of [3H]-thymidine incorporation regardless of its effect when used alone. The combination of all four growth factors was significantly more effective than all other combinations, demonstrating synergism in their action. Similar results were found in cell proliferation assays. In contrast to this, transforming growth factor-beta inhibited the ability of each of the other growth factors and serum-containing media to stimulate [3H]-thymidine incorporation. These data suggest that DNA synthesis in human retinal pigment epithelial cells can be modulated by several growth factors, some in a stimulatory or synergistic manner and at least one in an inhibitory manner. A better understanding of these complex interactions may provide insights relevant to normal and abnormal ocular wound healing.     

臂丛神经根性损伤膈神经移位术对青壮年患者早期呼吸功能的影响

目的研究臂丛神经损伤膈神经移位术对青壮年患者早期呼吸功能的影响.方法对16例接受膈神经移位治疗的患者,在术前、术后（10 d）进行肺功能指标的比较,同时定期进行门诊随访,观察呼吸系统自觉症状程度.结果13例术后出现了不同程度的供氧不足症状,16例全部出现一侧膈肌抬高,术后第10天肺活量（VC）、肺活量预计值百分数（VC%）分别比术前减少37.98%和26.88%,两者差异有统计学意义（tvc=11.532、tvc%=0,P＜0.01）.其它项目如残气量（RV）较术前轻度下降,肺总量（TLC）下降值达到术前肺总量的36.49%,残气量/肺总量比值（RV/TLC%）较术前上升了4.75%,上述各指标的差值均有统计学意义.1 s用力呼气量/用力肺活量比值（FEV1/FVC）和术前比基本无改变,但其差值有统计学意义.膈神经移位右侧（10例）与左侧（6例）术前、术后肺活量比较差异有统计学意义.术后随访8个月～2年,所有患者均无明显呼吸困难和胸闷等症状.结论膈神经移位术后对青壮年患者肺容量有较大的丧失,肺通气功能减弱和小气道阻力增加,但其丧失程度在机体自身代偿耐受范围内,不会导致急剧发生的严重呼吸功能障碍.建议对右侧臂丛神经根性损伤的患者,术前进行严格的肺、心功能检查,避免发生较为严重的并发症.     

Psychological Disturbance and its Associations in the Children of the Gujarati Community

The infrequent referral of Asian children to child psychiatry clinics was noted. By administering Rutter's scale A2 to samples of Gujarati and English parents with children between the ages of 4 and 7 years a lower rate of disturbance was demonstrated among the Asian sample providing an explanation for the original observation. Family and child-rearing factors associated with disturbance were identified.     

Comparative performance of three viral load assays on human immunodeficiency virus type 1 (HIV-1) isolates representing group M (subtypes A to G) and group O: LCx HIV RNA quantitative, AMPLICOR HIV-1 MONITOR version 1.5, and Quantiplex HIV-1 RNA version 3.0

The performance of the LCx HIV RNA Quantitative (LCx HIV), AMPLICOR HIV-1 MONITOR version 1.5 (MONITOR v1.5), and Quantiplex HIV-1 RNA version 3.0 (bDNA v3.0) viral load assays was evaluated with 39 viral isolates (3 A, 7 B, 6 C, 4 D, 8 E, 4 F, 1 G, 4 mosaic, and 2 group O). Quantitation across the assay dynamic ranges was assessed using serial fivefold dilutions of the viruses. In addition, sequences of gag-encoded p24 (gag p24), pol-encoded integrase, and env-encoded gp41 were analyzed to assign group and subtype and to assess nucleotide mismatches at primer and probe binding sites. For group M isolates, quantification was highly correlated among all three assays. In contrast, only the LCx HIV assay reliably quantified group O isolates. The bDNA v3.0 assay detected but consistently underquantified group O viruses, whereas the MONITOR v1.5 test failed to detect group O viruses. Analysis of target regions revealed fewer primer or probe mismatches in the LCx HIV assay than in the MONITOR v1.5 test. Consistent with the high level of nucleotide conservation is the ability of the LCx HIV assay to quantify efficiently human immunodeficiency virus type 1 group M and the genetically diverse group O.