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101.
背景和目的:罗格列酮与阿伐他汀联合疗法已经被证实对于2型糖尿病患者的血糖控制以及脂质水平都有益处。本试验将通过检测罗格列酮与阿伐他汀联合疗法对于2型糖尿病患者的生物标记水平的作用来研究该联合疗法对血管炎的作用。方法:30例患有2型糖尿病和高脂血症的患者被纳入治疗。对这些患者给予罗格列酮单一疗法4mg/d,持续3个月,然后在接下来的3个月中给予这些患者阿伐他汀10mg/d作为联合疗法。在研究开始时,罗格列酮单一疗法之后以及罗格列酮与阿伐他汀联合治疗之后测量炎性生物标记物,包括高敏C-反应蛋白(hs-CRP)、基质金属蛋白酶9(MMP…  相似文献   
102.
Newborn rabbits were given a single intravenous dose (100 mg/kg) of either alpha-tocopherol or alpha-tocopheryl acetate to compare disposition characteristics of these two forms of vitamin E. The resulting tissue concentrations of alpha-tocopherol and alpha-tocopheryl acetate differed significantly. Tissue concentrations of either form of vitamin E were much higher than those provided by normal nutrition, and remained unchanged (except in the liver) for 6 days after dose. alpha-Tocopheryl acetate was not completely converted to alpha-tocopherol, and only 50% of the dose was recovered 3 days after administration. The entire dose of alpha-tocopherol was recovered intact 3 days after administration. The persistence of very high tissue vitamin E concentrations after a single intravenous dosing, the disappearance from the body of half of the administered dose of alpha-tocopheryl acetate, and the lack of complete conversion of alpha-tocopheryl acetate to alpha-tocopherol when given intravenously have profound implications regarding the current clinical practice of giving repeated pharmacologic doses of vitamin E to newborn infants.  相似文献   
103.
目的探讨经肛门内镜显微手术(transanal endoscopicmic rosurgery,TEM)治疗直肠绒毛状腺瘤和早期直肠癌的疗效。方法1995年11月~2003年12月,我院行TEM治疗直肠肿瘤31例。全麻下根据肿瘤位置选择合适的体位,经肛门插入特殊的手术直肠镜,保持CO2充气状态,在立体视镜和腔镜系统下,采用针形电刀或5mm超声刀将直肠肿瘤完整切除(黏膜下或全层切除),手术创口在腔内连续缝合。结果31例直肠肿瘤均获完整切除,切缘均阴性。手术时间45~220min,平均95min;术中出血量0~180ml,平均40ml。手术并发症:暂时性排气失控2例,急性尿潴留1例,慢性阻塞性气道疾病急性发作1例,因服用阿斯匹林而出现继发性出血1例。术后病理分期:pT0期16例,pTis期2例,pT1期7例,pT2和pT3期各3例。31例随访2~92个月,平均23个月,肿瘤无原位复发。结论TEM是治疗直肠绒毛状腺瘤和早期直肠癌的一种安全、有效的微创手术方法。  相似文献   
104.
Lowy AM  Knight J  Groden J 《Surgery》2002,132(2):141-148
BACKGROUND: beta-Catenin is a component of the E-cadherin/catenin adhesion complex that maintains epithelial cell integrity. We have previously observed decreased beta-catenin expression in both human pancreatic cancer cell lines and primary tumors. To determine the significance of this finding with respect to pancreatic carcinogenesis, this study evaluated the effects of restoring expression of beta-catenin with and without E-cadherin in pancreatic cancer cells. METHODS: MiaPaca-2 cells were stably transfected with full-length cDNAs for beta-catenin, E-cadherin, or a mutated E-cadherin lacking the beta-catenin-binding domain. Doubly transfected cell clones containing beta-catenin and either E-cadherin or deleted E-cadherin were also selected. Assays for cell adhesion, cell cycle profile, motility, and apoptosis were performed. RESULTS: Cell clones expressing beta-catenin alone or beta-catenin and deleted E-cadherin did not differ significantly from the parental cell lines in any of the assays performed. In contrast, MiaPaca-2 cell clones expressing both beta-catenin and E-cadherin showed tight adhesion, decreased cell growth, and a significantly increased apoptotic index as compared to the parental line or singly transfected clones. CONCLUSIONS: MiaPaca-2 cells undergo apoptosis at a significantly increased rate after restoration of the E-cadherin/beta-catenin adhesion complex. This increase in apoptosis is dependent on the ability of E-cadherin to bind beta-catenin. Loss of beta-catenin expression may therefore provide pancreatic cancer cells with a growth advantage that contributes to tumor progression.  相似文献   
105.
106.
PURPOSE: To determine the transverse relaxation rates R2 and R2' from several gray matter regions and from frontal cortical white matter in healthy human brains in vivo and to determine the relationship between relaxation rates and iron concentration [Fe]. MATERIALS AND METHODS: Six healthy adults aged 19-42 years underwent thin-section gradient-echo sampling of free induction decay and echo magnetic resonance (MR) imaging at 3.0 T. Imaging covered the mesencephalon and basal ganglia. RESULTS: Relaxation rates (mean +/- SD) were highest in globus pallidus (R2 = 25.8 seconds-1 +/- 1.1, R2' = 12.0 seconds-1 +/- 2.1) and lowest in prefrontal cortex (R2 = 14.4 seconds-1 +/- 1.8, R2' = 3.4 seconds-1 +/- 1.1). Frontal white matter measurements were as follows: R2 = 18.0 seconds-1 +/- 1.2 and R2' = 3.9 seconds-1 +/- 1.2. For gray matter, both R2 and R2' showed a strong correlation (r = 0.92, P < .001 and r = 0.90, P < .001, respectively) with [Fe]. Although the slopes of the regression lines for R2' versus [Fe] and for R2 versus [Fe] were similar, the iron-independent component of R2' (2.2 seconds-1 +/- 0.6), the value when [Fe] = 0, was much less than that of R2 (12.7 seconds-1 +/- 0.7). CONCLUSION: The small iron-independent component R2', as compared with that of R2, is consistent with the hypothesis that R2' has higher iron-related specificity.  相似文献   
107.
108.
109.

The relationship between sex role identity and depression in nurses was explored. It was posited that nurses tend to be high in feminine traits and have traditional attitudes and that these traits and attitudes will be correlated with depressive symptoms. The sample consisted of 203 nurses employed at a 350‐bed metropolitan hospital. The research questionnaire included: (a) the Maferr Inventory of Feminine Values, (b) the Bem Sex Role Inventory, (c) the Zung Self‐Rating Depression Scale, and (d) demographic data. It was found that a strong and positive association existed between traditional attitudes toward feminine sex roles and depressive symptoms. However, relationships between feminine traits and depressive symptoms were not found. Data analysis also indicated statistically significant relationships between both androgenous traits, masculine traits, and lack of depressive symptoms. Limitations in scope and sampling procedures were discussed. In addition, the significance to nursing was discussed.  相似文献   
110.
Variables that have been conceptually linked with social vulnerability—income, educational level, employment, cessation of work to provide care, marital status, social support, and health—were used to predict four categories of reaction to caregiving in 159 daughters and daughters‐in‐law caring for their disabled aging parents. Social support, income, and health best predicted negative reactions to caregiving; social support alone best predicted feelings of family abandonment, impact on health, and impact on schedule. Compared with daughters and daughters‐in‐law who had not quit work to provide care, those who had quit work were significantly older, had lower incomes and fewer social supports, and were more involved in care. The results suggest that quitting work may be a precursor to social isolation that places the caregiver at increased risk for social vulnerability and negative reaction to caregiving. The implications of the findings for health care policy are discussed.  相似文献   
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