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131.
目的:观察白藜芦醇对豚鼠、小鼠和家兔离体心肌收缩力和心率的影响。方法:实验于2005-08/2006-12在河北医科大学西校区实验中心完成。①实验分组:离体豚鼠、小鼠和家兔心肌各分为9组:空白对照组、溶剂对照组、递增累积浓度白藜芦醇组(浓度为10-6,3×10-6,10-5,3×10-5,10-4,3×10-4mol/L),白藜芦醇对照组(5×10-5mol/L),ATP敏感性钾通道阻断剂格列苯脲(5×10-5mol/L)预孵育 白藜芦醇组,钙激活钾通道阻断剂四乙胺(10-3mol/L)预孵育 白藜芦醇组,电压依赖性钾通道阻断剂4-氨基吡啶(10-3mol/L)预孵育 白藜芦醇组,内向整流钾通道阻断剂氯化钡(10-4mol/L)预孵育 白藜芦醇组,乙酰胆碱调节钾通道阻断剂阿托品(10-5mol/L)预孵育 白藜芦醇组。②实验方法:不同类型的钾通道阻断剂均预孵育15min后,分别加入白藜芦醇(终浓度为5×10-5mol/L),连续记录30min,与相应动物白藜芦醇对照组相比较。③评估指标:分析不同阻断剂与白藜芦醇联用对心房收缩力下降率及心率抑制率的影响。结果:①白藜芦醇可降低豚鼠和小鼠离体心肌收缩力和心率(P<0.05),并被ATP敏感性钾通道阻断剂格列苯脲和钙激活钾通道阻断剂四乙胺部分阻断。②白藜芦醇可降低家兔离体心肌心率,格列苯脲可阻断白藜芦醇的负性变时作用。③电压依赖性钾通道阻断剂4-氨基吡啶、内向整流钾通道阻断剂氯化钡、乙酰胆碱调节钾通道阻断剂阿托品均不能阻断白藜芦醇对3种不同动物离体心房收缩力和心率的作用(P>0.05)。结论:白藜芦醇可呈剂量依赖性减慢豚鼠、小鼠和家兔的心率,白藜芦醇可减弱豚鼠心肌收缩力,其作用是与开放ATP敏感性钾通道有关,而与电压依赖性钾通道、内向整流钾通道和乙酰胆碱调节钾通道无关。同时,钙激活钾通道也参与了白藜芦醇对豚鼠和小鼠离体心房收缩力和/或心率的抑制作用。白藜芦醇对离体心肌收缩力和心率的作用有种属差异性。  相似文献   
132.
OBJECTIVE: To investigate the short- and long-term effects of a multidisciplinary postoperative rehabilitation programme in patients with femoral neck fracture. DESIGN AND SUBJECTS: A randomized controlled trial in patients (n = 199) with femoral neck fracture, aged >or= 70 years. METHODS: The primary outcomes were: living conditions, walking ability and activities of daily living performance on discharge, 4 and 12 months postoperatively. The intervention consisted of staff education, individualized care planning and rehabilitation, active prevention, detection and treatment of postoperative complications. The staff worked in teams to apply comprehensive geriatric assessment, management and rehabilitation. A geriatric team assessed those in the intervention group 4 months postoperatively, in order to detect and treat any complications. The control group followed conventional postoperative routines. RESULTS: Despite shorter hospitalization, significantly more people from the intervention group had regained independence in personal activities of daily living performance at the 4- and 12-month follow-ups; odds ratios (95% confidence interval (CI) ) 2.51 (1.00-6.30) and 3.49 (1.31-9.23), respectively. More patients in the intervention group had also regained the ability to walk independently indoors without walking aids by the end of the study period, odds ratio (95% confidence interval) 3.01 (1.18-7.61). CONCLUSION: A multidisciplinary postoperative intervention programme enhances activities of daily living performance and mobility after hip fracture, from both a short-term and long-term perspective.  相似文献   
133.
超声和微泡造影剂介导细胞基因转染的实验研究   总被引:4,自引:2,他引:4  
目的 探讨低频超声对细胞基因转染的作用。方法 超声治疗仪频率1MHz,脉冲重复频率100Hz,占空系数20%。质粒DNA为含编码绿荧光蛋白的pEGFP。应用荧光显微镜和流式细胞仪评价细胞基因转染率,台盼蓝染色计算细胞成活率。选用C2C12、3T3-MDEI和CHO3种细胞系为研究对象,加入DNA后辐照不同声强、时间或加入超声造影剂,观察各条件下的细胞基因转染率和成活率。结果 ①超声介导的基因转染与声强和辐射时间有关,最佳剂量为1w/cm^2 20s;②同样超声剂量,较高的声强较早达到最大基因转染率;③较低剂量时,微泡造影剂可使超声介导的基因转染提高2~3倍并可显著提高最高基因转染率。结论 低频超声可介导细胞基因转染,基因转染率不但与超声辐射剂量有关,而且同样剂量时,高声强较早达到最大基因转染率,最佳剂量是1w/cm^2 20s。同时,微泡造影剂可提高超声介导基因转染的最高转染率。  相似文献   
134.
目的:观察咬合垂直距离改变对无牙颌颞下颌关节紊乱病患者两侧颞颌关节髁状突位置的影响。方法:于1994-01/1997-12选择本院口腔修复门诊收治的无牙颌患者中符合颞下颌关节紊乱病诊断标准,同时垂直距离减低的患者48例。实验方案经医院伦理委员会审批,患者均知情同意。将48例无牙颌颞下颌关节紊乱病患者根据垂直距离减低程度的不同分为3组:减低1.8~6.0mm组18例,减低6.1~10.0mm组20例,减低10.1 ̄14.0mm组10例。通过重新制作一副全口义齿的方法治疗,咬合垂直距离恢复在合适的范围内,3组全口义齿的咬合垂直距离恢复前分别平均为63.4,60.6,54.2mm,恢复后咬合垂直距离分别平均为67.8,68.4,66.4mm,平均抬高4.4,7.8,12.2mm。通过拍摄正中颌位时颞下颌关节薛氏位X射线片测量各组前、后、上关节间隙。结果:垂直距离恢复前,减低1.8~6.0mm组关节后间隙,减低6.1~10.0mm组关节前、后间隙、减低10.1 ̄14.0mm组关节上、后间隙左右侧相比较,差异有显著性意义(P<0.05)。垂直距离恢复后,3组关节间隙左右侧差异无显著性意义。结论:无牙颌咬合垂直距离减低后可以导致两侧髁状突位置发生不对称改变。  相似文献   
135.
Abstract. Eeg‐Olofsson K, Cederholm J, Nilsson PM, Zethelius B, Svensson A‐M, Gudbjörnsdóttir S, Eliasson B (Institute of Medicine, Sahlgrenska University Hospital, University of Gothenburg, Gothenburg; Department of Public Health and Caring Sciences/Family Medicine and Clinical Epidemiology, Uppsala University, Uppsala; Department of Clinical Sciences, Lund University, University Hospital, Malmö; Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala; and Center of Registers in Region Västra Götaland, Gothenburg, Sweden) New aspects of HbA1c as a risk factor for cardiovascular diseases in type 2 diabetes: an observational study from the Swedish National Diabetes Register (NDR). J Intern Med 2010; 268 : 471–482. Aims. To analyse the association between glycosylated haemoglobin A1c (HbA1c) and cardiovascular disease (CVD) in patients with type 2 diabetes in the Swedish National Diabetes Register (NDR). Methods. An observational study of 18 334 patients (age 30–79 years, previous CVD in 18%, baseline HbA1c 5.0–10.9%) who were followed for 6 years (mean 5.6 years) from 1997/1998 until 2003. Results. Hazard ratios per 1% unit increase in baseline or updated mean HbA1c for fatal/nonfatal coronary heart disease (CHD), CVD and total mortality were 1.11–1.13, 1.10–1.11 and 1.09–1.10, respectively (all P < 0.001), adjusted for several risk factors and clinical characteristics in Cox regression. Adjusted 6‐year event rates increased with higher baseline or updated mean HbA1c with no J‐shaped risk curves, in all patients and also when subgrouping by shorter (mean 3 years) or longer (mean 14 years) diabetes duration, by presence or absence of previous CVD, or by treatment with oral hypoglycaemic agents (OHAs) or insulin. Risk reductions of 20% for CHD and 16% for CVD (P < 0.001) were found in patients with a baseline mean HbA1c of 6.5%, compared to those with a mean level of 7.5%. Compared to OHA‐treated patients, insulin‐treated patients had an increased risk of total mortality, due almost exclusively to an increased risk of non‐CVD mortality, and due less to a weakly significant increased risk of fatal CVD. HbA1c was not associated with non‐CVD mortality. Conclusions. This observational study showed progressively increasing risks of CHD, CVD and total mortality with higher HbA1c, and no risk increase at low HbA1c levels even with longer diabetes duration, previous CVD or treatment with either insulin or OHAs. Patients achieving HbA1c <7% showed benefits for risk reduction.  相似文献   
136.
Interaction between the immune system and cancer allows for the use of biological response modifiers, e.g. OK-432, in cancer therapy. OK-432, penicillin-killed Streptococcus pyogenes, is used in treating carcinomas, but also lymphangiomas. We have studied the role of monocytes (MOs) in the immune response to OK-432 by examining IL-6 and tumour necrosis factor (TNF)-α secretion after in vitro MO stimulation with OK-432, to some extent in comparison with lipoteichoic acid (LTA) and lipopolysaccharide (LPS). LTA stimulation of whole blood gave IL-6 but not TNF-α secretion, as previously shown with OK-432 stimulation, whereas both cytokines were secreted following LPS stimulation. Addition of the MAPK kinase (MAPKK) MEK inhibitor U0126 inhibited IL-6/TNF-α secretion in a dose-dependent manner. Flow cytometry and to some extent Western blot (Wb) analyses showed that MAPK ERK, located downstream of MEK1/2, is predominantly phosphorylated at isolation from peripheral blood. Addition of the p38 MAP kinase inhibitor SB202190 decreased MO IL-6/TNF-α production upon OK-432 stimulation in a dose-dependent manner. Addition of the MAPK JNK inhibitor SP600125 did not systematically change the MO IL-6/TNF-α OK-432 response. Flow cytometry showed that when stimulating the MOs before isolation from blood, LPS yielded ERK phosphorylation and LPS/LTA p38 phosphorylation, whereas OK-432 had no effects on phosphorylation levels. In conclusion, we have shown that OK-432 resembles TLR2 more than TLR4 stimulation of MOs and depends on MAPKK MEK and MAPK p38, but not on JNK phosphorylation. The MEK and p38 MO OK-432 stimulation dependence is possibly related to the differentiation of cells of the MO lineage.  相似文献   
137.
138.

Objective

To study the potential impact of health screening, with or without a motivational health dialogue, on the risk and morbidity of cardiovascular diseases (CVD) and diabetes (DM).

Design

Two cross-sectional studies with an interval of 11 years.

Setting

The community of Härnösand, Sweden.

Subjects

In the first study, 402 men born in 1934, 1944, or 1954 underwent health screening for CVD prevention in 1989. In the second study, 415 men (of the same ages) completed a questionnaire in 2000 (11 years later).

Main outcome measures

Odds ratio (OR) for self-reported CVD and DM.

Results

The odds ratio of self-reported CVD and DM was more than doubled among participants in the health screening without a health dialogue (OR 2.5; 95% CI 0.8–7.4) and threefold for those not participating (OR 3.0; 95% CI 1.0–8.8) compared with those who reported participation in health screening that included a structured health dialogue.

Conclusions

Health screening for the prevention of CVD and DM benefits from inclusion of a structured, motivational health dialogue.  相似文献   
139.
Prenatal substance exposure is associated with physical birth defects and increased risk of regulatory and neuropsychological difficulties of children born to mothers using substances while pregnant. Myriad factors, such as maternal psychopathology, stress, and poor living circumstances, may influence childhood development in addition to the teratological effect of prenatal substance exposure. This study explores the long-term developmental consequences in children from birth to age 7 born to women using substances and are in treatment. A series of t tests were performed to explore group effects on the cognitive and social dimensions of Griffiths Mental Development Scales compared with Swedish norms. The results showed significant effects on eye and hand coordination in children aged birth to 7 years and on hearing and speech, practical reasoning, and the general quotient in children aged 3 to 7 years. Children who were exposed primarily to alcohol in utero scored significantly lower on the personal and social skills subscale, eye and hand coordination subscale, and the general quotient than children exposed primarily to substances other than alcohol. These effects did not appear to be mediated by the mothers’ social background or treatment history. The results suggest that children who are exposed to substances, in particular alcohol, in utero are vulnerable overall, but especially in eye and hand coordination and personal and social skills.  相似文献   
140.
Abstract: The monitoring of viral DNA levels after transplantation is crucial for prevention of complications from cytomegalovirus (CMV) or Epstein–Barr virus (EBV) infection but there is no consensus as to which matrix is the most adequate. To compare serum and whole blood (WB) as specimens for measuring viral DNA, clinical samples from a 3‐year period were studied, with focus on cases where serum and WB were drawn on the same day. In 1896 paired serum and WB samples, CMV DNA was detected in both specimen types in 472 samples with 0.18 log higher levels (P<0.001) in WB than in serum (median level 2.73 vs. 2.56 log copies/mL), and in only either serum or WB in 127 and 108 samples, respectively, generally at levels below 1000 copies/mL. In 664 paired samples, EBV DNA was detected in both serum and WB in 160 samples, with 1.48 log higher levels (P<0.001) in WB (median 4.2 vs. 2.4 log copies/mL), in only WB in 227 cases with a median at 3.0 log copies/mL, and only in serum in 14 samples at low levels. The correlation between serum and WB DNA levels was weaker for EBV than for CMV (R2 0.31 vs. 0.74). We conclude that either serum or WB may be used for monitoring CMV and EBV DNA levels, that EBV DNA is detected post transplant in >50% of WB samples and at 30 times higher levels than in serum, and that post‐transplantation lymphoproliferative disorder (PTLD) may develop without further increase of EBV DNA in WB. Identification of PTLD may require EBV DNA testing in both specimen types or complementary tests.  相似文献   
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