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81.
适度健走锻炼对老年女性心肺功能的影响   总被引:3,自引:0,他引:3  
目的观察健走锻炼对老年女性心肺功能的影响。方法指导42名60~69岁的健康老年女性进行为期4个月的健走锻炼,根据心率控制行走速度和运动强度,试验前后分别测定受试者的心脏泵血功能、肺通气功能及脑阻抗血流图等。结果锻炼后,受试者的心脏泵血功能明显改善,每搏输出量由锻炼前的(65.22±11.41)ml增加到(72.10±10.78)ml;射血分数由(60.10±5.03)%增至(68.78±6.25)%;而心率则由(77.45±8.69)次/min减慢至(67.89±8.21)次/min;肺活量及每分钟最大通气量分别由(2.86±0.36)L和(96.14±15.21)L提高到(3.34±0.53)L和(114.02±16.01)L,锻炼前后相比均有非常显著性差异(P<0.01),反映脑血流阻力的指标流入时间由锻炼前的(0.171±0.058)s缩短至(0.128±0.049)s,亦有非常显著性差异(P<0.01)。结论适当强度的健走锻炼可改善老年女性的心肺功能,是一种简便易推广的健身运动项目。  相似文献   
82.
背景:毒蕈碱受体在调节逼尿肌细胞收缩过程中起重要作用,其受体亚型M3R直接介导逼尿肌细胞收缩。Ca2 是刺激逼尿肌细胞收缩的直接因素,Ca2 有数十种受体结合蛋白质,Ca2 通过与不同受体蛋白结合调节不同反应。目的:探讨Ca2 -钙调蛋白在M3R介导逼尿肌细胞收缩中的作用。设计:以逼尿肌细胞为观察对象,对比观察。单位:解放军第三军医大学西南医院泌尿中心。材料:实验在重庆西南医院中心实验室完成,实验动物选择健康雌性Wistar大鼠。方法:将原代培养逼尿肌细胞分为实验组和对照组,接种于6孔培养板上培养,实验组培养细胞70%融合时加入1×10-4mmol/L卡巴胆碱和毒蕈碱受体亚型M2R拮抗剂,分别阻断M3R、M2R,采用Ca2 浓度和钙调蛋白活性检测试剂盒分别测定两组逼尿肌细胞Ca2 浓度和钙调蛋白活性。主要观察指标:两组细胞内[Ca2 ]i浓度、钙调蛋白活性变化。结果:实验组的[Ca2 ]i和钙调蛋白的平均通道荧光对数值高于对照组(3.26±0.38,2.06±0.12,P<0.01);(2.87±0.34,2.14±0.24,P<0.05)。结论:实验结果提示Ca2 -钙调蛋白以信号传导途径参与了M3R介导逼尿肌细胞收缩的调节过程。  相似文献   
83.
Background and Aims: Kawasaki disease (KD) is the leading cause of acquired pediatric cardiac disease and requires a timely diagnosis. Available effective therapy is ideally administered within 10 days of illness diagnosis. Recent reports of several laboratory tests in KD have been published. In this study, we aimed to evaluate the sensitivity and specificity of several laboratory tests. Methods: We performed a retrospective study of consecutive patients diagnosed with KD from January to December 2008. We studied the sensitivity and specificity of several different tests [T‐cell subgroups, platelet count, erythrocyte sedimentation rate (ESR), and C‐reactive protein (CRP)] to predict KD using receiveroperator characteristic curve analysis. Results: No significant difference was demonstrated in T‐cell subgroups between patients with KD and referent patients (P>0.05). However, platelet count, ESR, and CRP were significantly higher in patients with KD than in referent patients (P<0.05). ESR showed a sensitivity of 93.9% and specificity of 83.3% with a cut‐off of 15 mm/hr (area under the curve [AUC], 89.1%; P=0.03). Platelet count showed a sensitivity of 70.6% and specificity of 75% with a cut‐off of 336.5×109/l (AUC, 71.2%; P=0.03). Conclusions: These results indicate that platelet count and ESR are good predictors of KD. J. Clin. Lab. Anal. 24:385–388, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
84.
Bortezomib, a novel dipeptide boronic acid proteasome inhibitor, has been shown in previous studies to be synergistic with gemcitabine; however, the molecular mechanisms are not fully understood. Because post-translational modification of proteins, such as ubiquitination and SUMOylation, plays a critical role in governing cellular homeostasis, we explored this further by treating human oropharyngeal carcinoma KB wild-type (KBwt) and gemcitabine-resistant (KBGem) cells with gemcitabine and bortezomib in a time-dependent and sequence-dependent manner. Treatment with bortezomib at 4 to 8 hours post-gemcitabine significantly induced cell death in KBwt cell lines. However, in KBGem cells, bortezomib alone was just as cytotoxic. Using reporter assays, nuclear factor-kappaB (NF-kappaB) activity was found to be 5-fold higher in KBGem cells than that in KBwt cells, and the combination treatment decreased NF-kappaB activity by 44% in KBwt cells and 28% in KBGem cells, respectively. By Western blot analyses, treatment with gemcitabine and bortezomib resulted in a cleavage of NF-kappaB in KBwt but not in KBGem cells. SUMOylation capacity was modulated by transducing KBwt and KBGem cells with lenti-SUMO-1 or the unconjugatable lenti-SUMO-1aa followed by drug treatment. The expression of cyclins A, D1, and E was differentially regulated by SUMOylation capacity in KBGem but not in KBwt cells. We report herein that the activation of NF-kappaB signaling plays a critical role in eliciting KBwt cell survival against gemcitabine, whereas the role of SUMOylation in modulating the steady-state levels of key cell cycle regulator proteins seems more significant in KBGem cells.  相似文献   
85.
Wu L  Li Z  Zhang Y  Zhang P  Zhu X  Huang J  Ma T  Lu T  Song Q  Li Q  Guo Y  Tang J  Ma D  Chen KH  Qiu X 《Molecular cancer therapeutics》2008,7(1):222-232
Hyperplasia suppressor gene (HSG), also called human mitofusin 2, is a novel gene that markedly suppresses the cell proliferation of hyperproliferative vascular smooth muscle cells from spontaneously hypertensive rat arteries. This gene encodes a mitochondrial membrane protein that participates in mitochondrial fusion and contributes to the maintenance and operation of the mitochondrial network. In this report, we showed that an adenovirus vector encoding human HSG (Ad5-hHSG) had an antitumor activity in a wide range of cancer cell lines. We further focused on the lung cancer cell line A549 and the colon cancer cell line HT-29 and then observed that Ad5-hHSG induced apoptosis both in vitro and in vivo. Confocal laser scanning microscopy and electron microscopy revealed that cells infected with Ad5-hHSG formed dose-dependent perinuclear clusters of fused mitochondria. Adenovirus-mediated hHSG overexpression induced apoptosis, cell cycle arrest, mitochondrial membrane potential (DeltaPsim) reduction and release of cytochrome c, caspase-3 activation, and cleavage of PARP in vitro. Overexpression of hHSG also significantly suppressed the growth of subcutaneous tumors in nude mice both ex vivo and in vivo. In addition, Ad5-hHSG increased the sensitivity of these cell lines to two chemotherapeutic agents, VP16 and CHX, and radiation. These results suggest that Ad5-hHSG may serve as an effective therapeutic drug against tumors.  相似文献   
86.
Song BC  Cui XJ  Kim H 《Intervirology》2005,48(2-3):133-137
OBJECTIVES: It has been reported that distribution of hepatitis B virus (HBV) genotypes shows geographic difference and are associated with clinical outcomes of HBV infection, including response to antiviral therapy and progression of chronic liver diseases. In this study, we analyzed the distribution of HBV genotypes according to the various clinical outcomes of chronic HBV infection in Korea, which is one of the most endemic areas of HBV infection. METHODS: A total of 200 patients with chronic HBV infection were enrolled. Clinical diagnoses of the 200 patients with chronic liver diseases were as follows: hepatitis B e antigen (HBeAg)-positive healthy carrier (defined as HBeAg(+), anti-HBe(-), HBV DNA(+) by hybridization, normal transaminase; n = 40); inactive HBsAg carrier (n = 40); chronic hepatitis B (n = 40); liver cirrhosis (n = 40); hepatocellular carcinoma (n = 40). HBV genotypes were determined by nested polymerase chain reaction using genotype-specific primers. RESULTS: All patients except 2 (inactive HBsAg carriers) were positive for nested PCR and they have genotype C regardless of clinical outcomes. CONCLUSIONS: HBV genotype was genotype C regardless of various clinical outcomes of chronic HBV infection in Korea. Considering that HBV genotypes have clinical relevance, distribution of HBV genotype in each area should be monitored when management for chronic HBV infection is planned.  相似文献   
87.
背景:皮肤缺损的常规修复方法多采用自体皮肤移植,需要健康供皮区且会遗留不同程度的瘢痕畸形。组织工程皮肤的成功构建并应用于临床,标志着皮肤缺损治疗的重大突破。目的:通过组织工程皮肤修复皮肤缺损,分析手术方法与愈合率的关系,为组织工程皮肤的临床应用提供实验依据。设计:随机对照观察。单位:解放军第四军医大学口腔医学院口腔颌面外科,组织病理学教研室,组织工程实验中心。材料:实验于2003-10/2004-03在解放军第四军医大学口腔医学院口腔组织工程实验中心完成。选用2.5-3月龄健康清洁级约克猪6只,随机分为3组:组织工程全层组、组织工程真皮+自体表皮组、自体移植组,2只/组。每只猪制作8个直径50mm的圆形皮肤缺损创面,16个创面/组,共48个创面。方法:①制备组织工程全层皮肤和组织工程真皮。②组织工程全层组:沿画线自脂肪层切除全厚皮肤,彻底止血,以湿生理盐水纱布覆盖创面备用,此时取出组织工程全层皮肤并于组织工程皮肤上均匀打引流孔以利引流,用生理盐水冲去组织工程皮肤表面的培养液,使表皮层向上平铺于创面上,注意与创面间不能产生气泡。其上分别覆盖单层油纱布,生理盐水纱布、无菌干纱布、弹性海绵垫,每层厚度约为3~5mm,常规打包包扎,最后再以弹性绷带加压包扎。③组织工程真皮+自体表皮组:以同样方法切除全厚皮肤,将取下的皮肤用取皮鼓反取厚约0.1~0.2mm的刃厚表皮泡于生理盐水中备用。以同样方法取出处理组织工程真皮后覆盖于创面上,即刻覆盖自体刃厚表皮。其余处理同组织工程全层组。④自体移植组:切除全厚皮肤并去除脂肪组织后,回植于自体创面,覆盖各层敷料,加压包扎。⑤每次换药打开创面时,移植皮肤无感染、坏死、脱落且直径不小于3mm即为成活,否则即为失败。于术后4周统计各组创面成活率。主要观察指标:术后4周各组移植皮肤成活情况。结果:术后4周时,组织工程全层组移植皮肤成活率75%,组织工程真皮+自体表皮组移植皮肤成活率87%,自体移植组移植皮肤成活率94%,3组比较基本相似(χ^2=2.34,P〉0.05)。结论:组织工程皮肤移植修复皮肤缺损的效果与自体表皮移植接近,证明组织工程皮肤修复皮肤缺损是可行的。  相似文献   
88.

Background

Valganciclovir is widely used to prevent post-transplant cytomegalovirus (CMV) infection in kidney transplant patients. However, the currently used dose remains controversial because the continuous use of this drug decreases kidney function and can induce leukopenia.

Objective

The purpose of this study was to measure the appropriate dose of valganciclovir required to prevent CMV infection.

Methods

A systematic review and meta-analysis were performed by using a random effects model. The Cochrane Central Register, MEDLINE, EMBASE, and PubMed databases were searched up to April 15, 2017. We conducted analysis on low-dose (450 mg) and standard-dose (900 mg) valganciclovir groups.

Results

After completion of the research, the analysis revealed that the glomerular filtration rate, graft loss, tacrolimus level, antibody-mediated rejection, and fungal and Candida infection rates did not differ between the 2 groups. However, the incidence of CMV tended to decrease in the low-dose group (0.584 [95% confidence interval [CI], 0.352–0.967]; P = .036). The biopsy-proven rejection rate decreased by 0.427 times in the low-dose group compared with the standard-dose group (95% CI, 0.274–0.667; P = .002). Furthermore, the incidence of leukopenia decreased by 0.371 times in the low-dose group compared with the standard-dose group (95% CI, 0.264–0.523; P = .001).

Conclusions

The 450-mg dose of valganciclovir effectively prevented post-transplantation CMV infection and decreased drug-induced side effects such as leukopenia. In the future, the lower dose of valganciclovir should be considered to prevent CMV infection and enhance cost-effectiveness.  相似文献   
89.
90.
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