角膜内皮炎的内皮细胞测量分析

目的研究角膜内皮炎角膜内皮细胞的变化。方法用角膜内皮镜检查角膜内皮炎患眼的角膜内皮细胞,分析内皮细胞密度和形态的改变。结果角膜内皮镜检查26只患眼,显示内皮细胞密度降低,细胞异形性比率增高。其中10只眼在抗病毒治愈后随访期间无复发,角膜内皮细胞密度未见进一步下降。结论单纯疱疹病毒是角膜内皮炎的主要感染源,可引起角膜内皮细胞的破坏。     

Expression of activated N-ras in a primary melanoma cell line counteracts growth inhibition by transforming growth factor-beta

One critical factor in melanoma progression is the change from radial growth phase to vertical growth phase. We previously showed a high incidence of ras mutations in progressing but not early human melanomas. We also found that stable expression of activated Ras in a primary human melanoma cell line (WM35) led to enhanced proliferation, anchorage-independent survival, migration and invasion in vitro and enhanced subcutaneous tumor formation in vivo, transforming the melanoma phenotype from the radial growth phase to the vertical growth phase. Inhibitory cytokines, especially transforming growth factor-beta, are important in homeostasis of normal human melanocytes. Proliferation of early melanoma cells can be inhibited by transforming growth factor-beta, whereas more aggressive stages lose this response. Using a transforming growth factor-beta activated luciferase reporter transiently transfected into WM35, WM35N-ras, and WM35H-ras (WM35 transfected with mutant N-ras or H-ras genes), we demonstrated significant decreases (p < 0. 04) in transforming growth factor-beta induced reporter expression in both ras transfected cell lines. Transforming growth factor-beta also induced significant decreases (p < 0.002) in the proportion of WM35 cells in S-phase of the cell cycle; this effect was not observed in WM35N-ras cells. Furthermore, we demonstrated that an important controlling factor in transforming growth factor-beta inhibition of cell cycle progression, the phosphorylation of the Rb protein, was altered in WM35N-ras; transforming growth factor-beta caused a marked relative increase in hypophosphorylated pRb in WM35 cells, but not in WM35N-ras. These data suggest that activated Ras plays an important part in melanoma progression from the radial growth phase to the vertical growth phase by counteracting inhibition by cytokines such as transforming growth factor-beta, thus providing a growth advantage.     

Induction of secreted matrix metalloproteinase-9 activity in human melanoma cells by extracellular matrix proteins and cytokines

Degradation of matrix proteins that constitute the dermal-epidermal junction and dermis by proteolytic enzymes is an essential step of melanoma invasion and metastasis, and this is primarily achieved by the matrix metalloproteinases. In this report, using zymography, we compared the basal secretion levels of active matrix metalloproteinase-2 and matrix metalloproteinase-9 to levels in response to various extracellular matrix proteins, cytokines, and growth factors in normal human melanocyte cells and melanoma cell lines from different stages of neoplastic progression. Basal matrix metalloproteinase-9 activity was only detected in vertical growth phase and metastatic melanoma cell lines, suggesting that matrix metalloproteinase-9 is a candidate biomarker for identifying vertical growth phase and metastatic melanomas. Most melanoma cell lines and cultured normal melanocytes produced high levels of matrix metalloproteinase-2. In addition, both tumor necrosis factor-alpha and interleukin-1beta are strong inducers of active matrix metalloproteinase-9 in vertical growth phase melanoma cell lines, indicating a possible role of these cytokines in the switch from radial growth phase to vertical growth phase. We propose that these proinflammatory cytokines promote melanoma invasion in part through upregulating matrix metalloproteinase-9. Both these cytokines are released from keratinocytes in the epidermis by ultraviolet radiation. Thus, our study suggests that the microenvironment of melanoma cells is an important feature in melanoma progression, and ultraviolet-radiation-induced cytokines might promote the progression of melanoma through the release or activation of matrix metalloproteinases.     

伯氨喹在乙醇—水混合溶剂中离解常数的测定及其与维生素C的配合比研究

本文推导出用pH滴定法测定三元弱酸离解解常数的方程,测得25±0.01℃时,伯氨喹在乙醇—水的体积比为1:1的混合溶剂中,离子强度范围5×10~(-3)～5×10~(-2)mol/L时逐级离解常数为Ka_1=(3.84±2.35)×10~(-2)(归属于仲铵基),Ka_2=(1.50±1.17)×10~(-8)(归属于叔铵基),Ka_3=(2.07±0.27)×10~(-10)(归属于伯铵基)。并用pH法及电导法测得伯氨喹与维生素C在上述溶剂中的配合比为1:1。     

红外热图监测微波辐照式全身热疗中体表温度的变化

目的：探讨利用红外热像仪监测微波辐照式全身热疗中体表温度的可行性。 方法：于2004-04/05选择在北京大学第一医院肿瘤中心参加全身热疗治疗的患者3例,女2例（分别为43岁和60岁,患有肺癌并已发生转移）,男1例（67岁,肺癌）。实验经医院伦理委员会批准,3例患者均知情同意。采用红外热像仪对3例全身热疗患者的体表温度进行定量测定和分析,重点考察局部血液循环相对较差容易造成热聚集的脸部、胸部、颈部、手部、小腿部、脚部的温度变化。治疗过程中同时对患者直肠温度实时监测。 结果：患者热疗前后全身各部位体表的热状态易于显示在监视器上,有助于整个治疗过程的进程控制及评价。3例患者中只有1例的脚背部温度稍有升高,但未出现皮肤烫伤。 结论：使用红外热像仪监测全身热疗中人体表面温度特别是局部血液循环较差的四肢具有重要的参考价值,可有效防止皮肤烫伤。     

The effects of a reminiscence education program on baccalaureate nursing students' cultural self-efficacy in caring for elders

The increase in our minority elder population has created a need to develop innovative programs that prepares students who are competent in gerontological nursing skills and sensitive to cultural differences. The purpose of this pilot study was to test the effects of a reminiscence education program on BSN students' cultural self-efficacy in caring for elders. An interrupted time series design with a nonequivalent, no-treatment control group was used with 64 nursing students recruited from a northeast university in the United States. The intervention consisted of a two-hour reminiscence education program and a 13 week period in which the experimental group implemented integrative reminiscence with elders during their community health practicum. The eldercare cultural self-efficacy scale was the outcome measure. Results indicated that students receiving the reminiscence education program demonstrated significantly higher levels of eldercare cultural self-efficacy F(1, 62)=5.34, p=0.024 than those not receiving the intervention. Reminiscence education programs implemented as part of clinical practicums may assist to increase nursing students' perceptions of confidence in caring for elders. Implications for nursing education and the care of diverse elders are discussed.