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91.
目的探讨人流术室内空气中单位时间氧化亚氮的变化及对人的影响。方法对80例行人流手术患者在手术前、术者持续工作60min、术者持续工作70min和通风30min分别采样80、40、40、80份,并进行不同时段比较。结果手术70min 92.5%样本N2P释放量〉0.15mg/m^3,与手术前、手术60min及通风30min比较,差异有显著性意义(均P〈0.01)。结论氧化亚氮在无痛人流术操作过程中,时间〉60min会引起人体不适,需采取通风换气的措施,才能使空气净化。 相似文献
92.
Objective: To investigate the anti-inflammatory effect of erythropoietin (EPO) pretreatment on cardiomyocytes exposed to hypoxialreoxygenation injury (H/R) and explore the possible mechanism.
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
93.
两种不同术式治疗下肢静脉功能不全的近期疗效对照研究 总被引:1,自引:1,他引:0
目的 评价腔内射频闭合术联合TriVex刨吸术治疗下肢静脉功能不全的疗效. 方法 150例下肢静脉功能不全患者(150条患肢)随机分为A、B两组,每组75例.A组行大隐静脉射频闭合术联合曲张浅静脉TriVex刨吸术,B组行大隐静脉高位结扎抽剥术联合曲张浅静脉TriVex刨吸术.比较两组手术情况、术后4周患者对手术的自身评价、手术前后CEAP(clinic,etiologic,anatomic and pathophysiological classification)分级和临床严重程度计分(venous clinical severity score,vcss)的变化.结果 A、B两组手术时间分别为(67±11)min和(69±9)min(P>0.05),A组术后疼痛轻、下地时间早、住院天数少、皮下血肿发生率低,但皮下硬结发生率高于B组;对手术的评价A组为(11.21±2.00)分优于B组(10.52±2.08)分,差异有统计学意义(P<0.05);两组手术前后CEAP分级和VCSS计分变化差异均有统计学意义(P<0.01),A、B两组手术前后VCSS分差为(4.6±2.5)分和(4.3±2.7)分(P>0.05).结论 利用射频闭合术联合TriVex刨吸术治疗下肢静脉功能不全有效,且微创、并发症少.CEAP临床分级和VCSS临床记分可用于其疗效评价. 相似文献
94.
萧淑芳 《中国中医基础医学杂志》2007,13(3):177-177
络脉系统是经络系统的重要组成部分,但络脉具有独特的生理功能与病理变化,络脉病变是多种内伤杂病和外感重症发生、发展、变化的重要因素之一。络脉学说肇始于《内经》。《内经》对络脉的生理特点、病理变化以及在临床诊断、治疗中的应用等内容已有较完备的记载,奠定了络脉学说 相似文献
95.
Objective To investigate effects of angiotcnsin ( 1-7 ) [ Ang( 1-7 ) ] and enalaprilat on function of isolated rat heart perfused by burn serum. Methods Eighty SD rats were used to prepare burn serum. Hearts of another 24 SD rats were isolated to reproduce Langendorff perfusion model. The rat hearts were divided into different groups with different perfusion fluids as K-H buffer group, K-H buffer containing 20% burn serum group ( burn serum group) , K-H buffer containing 20% burn serum and 2 μg/mL enala-prilat group (enalaprilat group), and K-H buffer containing 20% burn serum and 1 nmol/mL Ang(1-7) group [ Ang(1-7) group]. The rat hearts were perfused for 30 mins with each of above-mentioned fluids in different groups. Then left ventrieular systolic pressure (LVSP) , left ventricular end diastolic pressure ( LV-EDP) , ± dp/dt max, coronary flow(CF) , level of creatine kinase (CK) and lactate dehydrogenase (LDH) in respective coronary effluent were determined. Results Compared with LVSP ( 11.2 ± 1.0 kPa, 1 kPa = 7.5 mm Hg), +dp/dt max (642±53 kPa/s), -dp/dt max (380±61 kPa/s) and CF level in K-H buffer group, CF, LVSP(5.9±0.8, 8.0±1.1, 8.9±1.3 kPa, respectively), +dp/dt max(275±37, 454±48, 479±63 kPa/s, respectively), - dp/dt max ( 135±35, 219±47, 277±58 kPa/s, respectively ) of burn serum group, those levels in Ang(1-7) group, and enalaprilat group were decreased obviously(P<0.05 or P <0.01 ), but LVEDP, level of CK and LDH in coronary effluent were increased. Compared with those parameters in burn serum group, CF, LVSP, ±dp/dt max of Ang(1-7) group and enalaprilat group were increased obviously(P<0.05 or P<0.01), and LVEDP, level of CK and LDH in coronary effluent were decreased obviously(P<0.01). Conclusions Ang(1-7) and enalaprilat can effectively improve left ventricular function of isolated rat heart perfused by burn serum and mitigate myocardial injury. 相似文献
96.
卵圆孔未闭动物模型的建立 总被引:1,自引:0,他引:1
目的 探讨采用正常中华小型猪制作卵圆孔未闭动物模型的可行性。方法 中华小型猪11只,选取1只行预实验,10只用于正式实验。全身麻醉下,经股静脉送入Rups-100穿刺针系统,在透视引导下穿刺房间隔卵圆窝,然后对穿刺点行球囊扩张术。预实验动物术后1d处死,正式实验组动物术后21d处死。心脏取材,行病理检查。结果 11只猪均成功行房间隔穿刺和球囊扩张术,并经心房造影证实建立卵圆孔未闭模型。正式实验组动物除1只术中出现心包积液外,其余术中及术后均无并发症。预实验动物于处死后肉眼观房间隔卵圆窝有-0.7cm×0.8cm缺损,光学显微镜下见红细胞聚集。正式实验组动物于处死后观察,7只可见房间隔卵圆窝愈合,3只分别残留0.1cm×0.2cm、0.2cm×0.2cm、0.1cm×0.3cm缺损。正式实验组动物无论卵圆窝是否愈合,光学显微镜下在穿刺点周围均可见不同程度的局灶性心内膜增生和缺失、淋巴细胞聚集、心肌细胞肿胀、坏死和间质纤维化。结论 采用房间隔穿刺和球囊扩张的方法,用中华小型猪建立卵圆孔未闭模型是可行的。 相似文献
97.
目的探讨低铁与低热量饮食是否能延缓糖尿病肾病的进展。方法以168例Ⅱ型糖尿病肾病患者为研究对象,随机分为两组,对照组予以常规治疗,治疗组在进行同样常规治疗的同时,予低铁、低热量饮食。结果平均随访37±22个月,治疗组患者血清铁水平显著降低,与对照组比较,有显著差异(P<0.01);治疗组血清肌酐189±78μmmol/L,对照组257±115μmmol/L,两组比较,有显著差异(P<0.01)。治疗组有6例患者达到终止随访目标,血红蛋白低于80g/L和或红细胞压积<33%,需进行促红素治疗,占17.6%;对照组有10例达到终止目标,占35.7%,两组比较,有显著差异(P<0.01)。结论低铁饮食治疗能显著降低糖尿病肾病患者铁负荷,配合低热量饮食治疗,能明显延缓糖尿病肾病的进展。 相似文献
98.
99.
正位可控性去带盲结肠膀胱术的疗效观察 总被引:4,自引:1,他引:3
目的:探讨正位可控性去带盲结肠膀胱术的临床疗效.方法:对17例膀胱肿瘤患者行膀胱全切除术后,应用末段回肠及盲升结肠作贮尿囊行正位膀胱重建术.结果:17例中15例获随访6~24个月,平均14.5个月.全组无严重并发症,均无瘤生存;术后3周自主可控性排尿,日间排尿可控率为93.3%,1年夜间尿失禁22.2%.术后6个月尿动力学检查,膀胱容量336 ml、最大尿流率13.7 ml/s、剩余尿量42 ml,而充盈期膀胱压力明显低于尿道闭合压.输尿管反流1例,但无尿道、输尿管狭窄,肾功能正常.结论:正位可控性去带盲结肠膀胱术具有膀胱容量大、内压低,正位排尿,可控性好,且手术操作简单、并发症少等优点,患者易于接受,是一种较理想的尿流改道方式. 相似文献
100.
YOU Han XIAO Bing CUI Da-Xiang SHI Yong-Quan FAN Dai-Ming 《World journal of gastroenterology : WJG》1998,4(4)
AIM To clone novel gastric cancer-associated genes and investigate their roles in gastric cancer occurrence.METHODS A method called differential display was used which allows the identification of differentially expressed genes by using PAGE to display PCR-amplified cDNA fragments between gastric cancer cells and normal gastric mucosa cells. These fragments were cloned into plasmid vector pUC18. Homology analysis was made after sequencing these fragments.RESULTS Two novel genes were identified compared with sequences from GenBank. One was registered with the AD number AF 051783. In situ hybridization showed that these two novel genes expressed specifically in gastric cancer tissues.CONCLUSION The two novel genes obtained by differential display were confirmed to be gastric cancer-associated genes using in situ hybridization. 相似文献