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71.
纪悦 《基层医学论坛》2006,10(5):399-400
目的 探讨在临床上上颌第一磨牙近中颊根第二根管(MB2)的发现及扩通。方法 在25例需要进行根管治疗的上颌第一磨牙上寻找MB2,若无法找到,使用超声根管异物清除工作尖10P清理髓底及慢速圆钻去除预计位置部分牙本质,再次寻找。找到后通畅根管,若无法扩通,使用慢速圆钻在MB2根管口处向根方去除少量牙本质。结合使用EDTA再次通畅根管。结果 25颗治疗齿中有13颗找到MB2(52%),其中2颗是在超声根管锉清理髓室底后发现的,4颗在进一步去除MB2根管口位置的牙本质后发现。8颗治疗齿的MB2通畅(32%),其中3颗自然扩通,5颗在去除MB2根管口处部分矛本质并使用EDTA后通畅。结论 临床上上颌第一磨牙MB2发现率为52%。扩通率为32%。掌握MB2的解剖位置,使用超声方法以及EDTA可提高MB2的发现率和扩通率。  相似文献   
72.
BACKGROUND: Thrombolysis therapy is not suitable for the elderly patients with acute ischemic stroke who delayed to be diagnosed for more than 3 hours, but traditional medicine is also not very ideal.OBJECTIVE: To observe the clinical therapeutic effect of modified hemodilution combined therapy applied in elderly patients with acute cerebral thrombosis and analyze the mechanism of this therapeutic method.DESIGN: 1:1 paired grouping according to gender and controlled observation.SETTING: Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University.PARTICIPANTS Totally 90 elderly patients with acute ischemic stroke who received the treatment in the Cadre Ward and Mental Ward, Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University from March 1996 to June 2004 were recruited. They all met the diagnosis criteria revised by the Fourth Academic Conference of National Cerebrovascular Diseases in 1995 and were diagnosed as acute ischemic stroke by skull CT. They were informed of therapeutic plan and detected items.According to 1:1 paired principle in gender, 90 enrolled patients were assigned into treated group (n=45)and control group (n=45). There were 39 male and 6 female in the treatment group, and they were aged (76±6)years, ranging from 71 to 84 years, and hospitalized at the 14th to 76th hours after onset. There were 39 male and 6 female in the control group, and they were aged (76±6)years , ranging from 70 to 82years, and hospitalized at the 16th to 72th hours after onset.METHODS: Therapeutic method: Patients of treated group received modified hemodilution combined therapy.200 mL whole blood of patients was exchanged with 500 mL dextran-40 (including 20 mL danshen parenteral solution and 32 mg heparin) at the beginning of therapy; From the 2nd day, compound huangqi tea bag (Huangqi mainly, including danshen, honghua, chuanxiong, shishao and a little acetyl salicylic acid) was made, twice a day, 1 bag once. At the same time, the above-mentioned dextran-40 liquid of 500 mL was intravenously injected, once a day, 14 days in total; On the 6th day after therapy, the above-mentioned aseptic autoblood stored in refrigerator at 4 ℃ was transfused back into the patients following pre-treatment of high-concentration oxygenation and ultraviolet irradiation by light quantum instrument. Patients of control group were intravenously injected of 0.4 g venoruton(Traditional Chinese medicine compound parenteral solution for promoting blood circulation and removing blood stasis ) and 50 g/L glucose of 500 mL, 75 mg coagulation index, change of platelet aggregation rate and change of hemorrheology of patients in two groups were monitored before and after therapy. The level of blood lipid of patients in two groups was measured with American Beckman automatic biochemistry analyzer. Blood flow rate of middle cerebral artery of resting electrocardiogram were measured with American HP SONOS 2500 sonoscope. Neuro-dysfunction score revised in the national conference (1995) was used to evaluate the recovery of neurological function effect were observed at the same time.effect of drug.RESULTS: Totally 90 patients were enrolled in the experiment. One patient from treated group died of hyperosmolar nonketotic diabetic coma of complicated diabetes mellitus. One patient from control group died ulation index and platelet aggregation rate: prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) of patients after therapy were significantly longer than those before therapy in the treated group and those after therapy in control group [After therapy in treated group: (18.4±1.9),(41.8±2.1), (19.7±1.7)s, Before therapy in treated group: (13.4±1.3), (35.8±1.3), (12.5±0.9)s, After therapy in control group: (16.9±1.5), (39.1±1.1), (11.9±2.1) s, P < 0.05] ;Concentration of fibrinogen (Fbg) after therapy was significantly lower than that before therapy in the treated group and that after therapy in control group[After therapy in treated group: (3.4±0.4) g/L; Before therapy in treated group: (4.3±0.7) g/L;After therapy in control group:(4.0±0.6) g/L; P < 0.05]. Platelet aggregation rate decreased from (37.92of total cholesterol (TC), triacylglycerol(TG) and Iow density lipoprotein cholesterol (LDL-C) of patients after therapy were significantly lower than those before therapy in treated group and those after therapy in control group [After therapy in treated group: (5.2±0.9), (1.9±0.9), (2.08±1.1) mmol/L, before therapy in treated group:(5.9±1.2), (2.8±0.9), (3.94±0.5) mmol/L, After therapy in control group: (6.0±1.1), (2.6±0.8), (3.84±0.9) mmol/L,after therapy than before therapy [Before therapy: (43.84±4.55)% ;After therapy: (40.48±4.02)% ;P < 0.05].cantly lower than of control group 14 days after therapy. The total effective rate after therapy was signifiadverse effect.CONCLUSION: Modified hemodilution combined therapy can improve hemorheology, decrease hematocrit,increase blood flow rate of middle cerebral artery, so as to improve the impaired clinical neurological function of elderly patients with acute cerebral thrombosis through anticoagulation and antiplatelet aggregative activity as well as regulating blood lipid.BACKGROUND: Thrombolysis therapy is not suitable for the elderly patients with acute ischemic stroke who delayed to be diagnosed for more than 3 hours, but traditional medicine is also not very ideal.OBJECTIVE: To observe the clinical therapeutic effect of modified hemodilution combined therapy applied in elderly patients with acute cerebral thrombosis and analyze the mechanism of this therapeutic method.DESIGN: 1:1 paired grouping according to gender and controlled observation.SETTING: Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University.PARTICIPANTS:Totally 90 elderly patients with acute ischemic stroke who received the treatment in the Cadre Ward and Mental Ward, Department of Internal Medicine, Chengzhanyuan District, First Hospital Affiliated to Zhejiang University from March 1996 to June 2004 were recruited. They all met the diagnosis criteria revised by the Fourth Academic Conference of National Cerebrovascular Diseases in 1995 and were diagnosed as acute ischemic stroke by skull CT. They were informed of therapeutic plan and detected items.According to 1:1 paired principle in gender, 90 enrolled patients were assigned into treated group (n=45)and control group (n=45). There were 39 male and 6 female in the treatment group, and they were aged (76±6)years, ranging from 71 to 84 years, and hospitalized at the 14th to 76th hours after onset. There were 39 male and 6 female in the control group, and they were aged (76±6)years , ranging from 70 to 82years, and hospitalized at the 16th to 72th hours after onset.METHODS: Therapeutic method: Patients of treated group received modified hemodilution combined therapy.200 mL whole blood of patients was exchanged with 500 mL dextran-40 (including 20 mL danshen parenteral solution and 32 mg heparin) at the beginning of therapy; From the 2nd day, compound huangqi tea bag (Huangqi mainly, including danshen, honghua, chuanxiong, shishao and a little acetyl salicylic acid) was made, twice a day, 1 bag once. At the same time, the above-mentioned dextran-40 liquid of 500 mL was intravenously injected, once a day, 14 days in total; On the 6th day after therapy, the above-mentioned aseptic autoblood stored in refrigerator at 4 ℃ was transfused back into the patients following pre-treatment of high-concentration oxygenation and ultraviolet irradiation by light quantum instrument. Patients of control group were intravenously injected of 0.4 g venoruton(Traditional Chinese medicine compound parenteral solution for promoting blood circulation and removing blood stasis ) and 50 g/L glucose of 500 mL, 75 mg acetosal was taken orally, once a day, 14 days in total. ② Measurement and observation of index: Blood coagulation index, change of platelet aggregation rate and change of hemorrheology of patients in two groups were monitored before and after therapy. The level of blood lipid of patients in two groups was measured with American Beckman automatic biochemistry analyzer. Blood flow rate of middle cerebral artery of resting electrocardiogram were measured with American HP SONOS 2500 sonoscope. Neuro-dysfunction score revised in the national conference (1995) was used to evaluate the recovery of neurological function of the patients in two groups at the 3rd, 5th, 7th and 14th days after therapy. ③Therapeutic effect and adverse effect were observed at the same time.MAIN OUTCOME MEASURES: ① Changes of coagulation index, blood lipid level and hemorheology; ② Blood flow rate of middle cerebral artery and NDS of patients with acute ischemic stroke in two groups; ③Adverse effect of drug.RESULTS: Totally 90 patients were enrolled in the experiment. One patient from treated group died of hyperosmolar nonketotic diabetic coma of complicated diabetes mellitus. One patient from control group died of severe pulmonary infection. The rest 88 patients entered the stage of result analysis. ① Change of coagulation index and platelet aggregation rate: prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) of patients after therapy were significantly longer than those before therapy in the treated group and those after therapy in control group [After therapy in treated group: (18.4±1.9),(41.8±2.1), (19.7±1.7)s, Before therapy in treated group: (13.4±1.3), (35.8±1.3), (12.5±0.9)s, After therapy in control group: (16.9±1.5), (39.1±1.1), (11.9±2.1) s, P < 0.05] ;Concentration of fibrinogen (Fbg) after therapy was significantly lower than that before therapy in the treated group and that after therapy in control group[After therapy in treated group: (3.4±0.4) g/L; Before therapy in treated group: (4.3±0.7) g/L;After therapy in control group:(4.0±0.6) g/L; P < 0.05]. Platelet aggregation rate decreased from (37.92±0.85)% before therapy to (26.42±1.01)% after therapy (P < 0.01). ②Change of blood lipid level: Levels of total cholesterol (TC), triacylglycerol(TG) and Iow density lipoprotein cholesterol (LDL-C) of patients after therapy were significantly lower than those before therapy in treated group and those after therapy in control group [After therapy in treated group: (5.2±0.9), (1.9±0.9), (2.08±1.1) mmol/L, before therapy in treated group:(5.9±1.2), (2.8±0.9), (3.94±0.5) mmol/L, After therapy in control group: (6.0±1.1), (2.6±0.8), (3.84±0.9) mmol/L,P < 0.05]. ③ Change of hemorheology index: Hematocrit of patients of treated group was significantly lower after therapy than before therapy [Before therapy: (43.84±4.55)% ;After therapy: (40.48±4.02)% ;P < 0.05].④ Blood flow rate of middle cerebral artery of patients of treated group was significantly lower before therapy than after therapy [(90±1.2), (97±2.1) cm/s,P < 0.01]. ⑤ NDS of patients in treated group was significantly lower than of control group 14 days after therapy. The total effective rate after therapy was significantly higher in the treated group than in the control group (93%,78%, P < 0.05). ⑥There was no obvious adverse effect.CONCLUSION: Modified hemodilution combined therapy can improve hemorheology, decrease hematocrit,increase blood flow rate of middle cerebral artery, so as to improve the impaired clinical neurological function of elderly patients with acute cerebral thrombosis through anticoagulation and antiplatelet aggregative activity as well as regulating blood lipid.  相似文献   
73.
人工肱骨头置换术治疗高龄复杂肱骨近端骨折   总被引:2,自引:0,他引:2  
目的探讨和分析采用人工肱骨头置换术治疗复杂肱骨近端骨折的适应证、手术技术要点和早期疗效。方法对12例肱骨近端四部分骨折伴肱骨头脱位的高龄患者,早期手术行人工肱骨头置换。手术采用三角肌胸肌间入路,先复位大小结节,确定假体高度,骨水泥固定假体保持30°左右的后倾,大小结节再复位固定,必要时取骨折的肱骨头自体骨植骨,术后早期功能锻炼。结果术后平均随访16.6个月,术后未发生感染、神经损伤、关节脱位和假体周围骨折。采用Neer评分系统评定人工关节功能,平均为84.4分,90分以上(优)3例,80~89分(满意)7例,70~79分(不满意)2例,满意率为83.3%。12例患者疼痛方面平均得分为33.5分,功能方面为25.6分,运动方面为16.5分,解剖重建方面为8.8分。结论在正确选择手术适应证、掌握手术技术以及合理的术后康复等前提下,人工肱骨头置换术是治疗高龄患者复杂肱骨近端骨折的有效方法,尤其在减轻创伤后肩关节疼痛方面效果最为显著。但在恢复肩关节活动度方面仍欠满意,需加强对患者术后关节康复训练的指导工作。  相似文献   
74.
兔关节软骨细胞的分离、培养和形态学特征   总被引:9,自引:2,他引:7  
[目的]探讨兔关节软骨细胞的分离、培养方法,观察单层高浓度培养时细胞表型表达情况.[方法]无菌条件下,从 2周龄新西兰白兔的颞颌关节及四肢关节髁突面削取软骨片,采用机械-酶消化法分离软骨细胞,经台盼蓝拒染计数,将细胞按 1× 106个 /孔接种于 6孔培养板,传代培养,描绘生长曲线.利用相差显微镜及透射电镜观察细胞形态.应用甲苯胺蓝及Ⅱ型胶原免疫组化对细胞进行鉴定.[结果]每克软骨能获取 1 5× 106个软骨细胞,活性率为 95%.培养 2~ 3 d,细胞贴壁、变形,呈多角形; 8 d左右,细胞融合成层.透射电镜观察显示细胞核圆形,有丰富的粗面内质网、高尔基体及分泌的基质成分.甲苯胺蓝及Ⅱ型胶原染色阳性.细胞传至 5代后,出现"成纤维细胞样".[结论]本研究建立了简单易行的软骨细胞分离、培养方法;初代、第 2代细胞生长良好,适合于实验研究;软骨细胞 5代培养后,细胞表型发生改变.  相似文献   
75.
烧伤后早期应用中/长链甘油三酯对患者免疫功能的影响   总被引:5,自引:1,他引:4  
目的 探讨烧伤后早期肠内喂养中链甘油三酯 (MCT) /长链甘油三酯 (LCT)对机体免疫功能的影响及其可能机制。 方法 选取 30例烧伤面积 >30 %TBSA的患者 ,随机分为两组 (每组 15例 )。F组 ,饲以含MCT/LCT的肠内营养制剂Fresubin 75 0MCT ;N组 ,饲以只含LCT的肠内营养制剂Nutrison。于伤后 2 4h内进行完全肠内营养支持 ,共持续 10d。于伤后 1、4、7、10d检测两组患者血浆白细胞介素 (IL) 2、IL 4、前列腺素 (PG)E2 及外周血T淋巴细胞转化率的改变。 结果 伤后各时相点F组患者血浆IL 2水平与N组相比 ,无明显差异 (P >0 .0 5 ) ;伤后 4dF组PGE2 水平较N组明显降低 (P <0 .0 1) ;伤后 4、7、10dF组IL 4水平及外周血T淋巴细胞转化率均明显高于N组 (P <0 .0 5~ 0 .0 1)。 结论 在改善烧伤后机体的免疫功能方面 ,含MCT/LCT的肠内营养制剂较单纯LCT制剂更具优势。  相似文献   
76.
目的: 观察细胞内游离Ca2+([Ca2+]i)在培养的不同发育阶段皮层神经元无镁诱导惊厥性损伤中的作用,探讨惊厥性脑损伤年龄依赖性的可能机制.方法:体外培养6 d、17 d的胚胎大鼠皮层神经元用无镁细胞外液处理3 h,或于无镁处理前用NMDA(N-甲基-D-门冬氨酸)受体拮抗剂或Ca2+通道阻滞剂预处理,用MTT代谢率测定的方法检测神经元损伤,以Fluo-3作标记用激光共聚焦显微镜扫描的方法检测[Ca2+]i.结果:体外培养6 d、17 d的神经元单纯无镁组MTT代谢率较同期对照组降低.应用MK-801 10 μmol*L-1、AP-5 50 μmol*L-1、尼莫地平10 μmol*L-1预处理后再给无镁处理,培养6 d、17 d的神经元MTT代谢率均不同程度高于同期单纯无镁组.培养6 d、17 d的神经元相对荧光强度之间差异有显著性,两者与基线荧光强度比较差异亦有显著性.应用上述各种拮抗剂后,[Ca2+]i改变的峰值均明显低于同期单纯无镁组.结论: 在体外不同发育阶段的神经元,短暂无镁处理诱导惊厥样放电所引起的神经元线粒体功能损伤以及[Ca2+]i改变程度不同.这种[Ca2+]i改变的年龄依赖性可能是惊厥导致神经元损伤的年龄依赖性的机制之一.NMDA受体-Ca2+通道激活是导致这种[Ca2+]i改变及神经元损伤的关键环节.  相似文献   
77.
目的单因素观察吸入性损伤或烧伤后血清免疫反应性降钙素(iCT)的变化,分析其诊断意义。方法将24只犬随机分为单纯吸入性损伤后中度(A)、重度(B)、特重度损伤(C)组及单纯重度烧伤(D)组,每组6只。吸人性损伤犬均在伤后6 h行纤维支气管镜检查,以明确其损伤程度。分别于不同时相点抽取犬静脉血检测iCT含量,抽取动脉血做血气分析。结果(1)经纤维支气管镜检查,证实A、B、C组犬符合吸入性损伤的预期程度。(2)与伤前值(38±22)ng/L比较,各组吸人性损伤犬iCT含量在伤后1 h均明显升高(P<0.05),伤后4 h明显高于D组(P(0.05),其中A组于24 h达峰值(453±224)ng/L,B、C组在48 h内呈进行性升高。D组犬iCT含量在伤后2 h开始持续升高,至伤后48 h为(125±41)ng/L。(3)血气分析结果显示,与伤前值(109±8)mm Hg (1 mm Hg=0.133 kPa)比较,A、D两组氧分压(PaO2)伤后各时相点无明显差异(P>0.05),B、C组犬从伤后8 h和伤后4 h开始持续下降,分别为(65±6)、(71±9)mm Hg。与二氧化碳分压(PaCO2)的伤前值(38±5)mm Hg比较,C组犬伤后24 h PaCO2开始升高[(52±11)mm Hg]。结论在吸入性损伤后8 h内,iCT的变化明显早于血气分析指标,其诊断意义接近纤维支气管镜检查。  相似文献   
78.
目的:通过噬菌体展示技术筛选iNOS特异性抑制肽。方法:将iNOSFAD结合区及其附近序列的基因片段装入pET-28A( ),在大肠杆菌BL21中表达,His.bind^TM亲和层析柱纯化目的蛋白,使用纯化蛋白筛选Ph.D.-12^TM噬菌体库,筛选iNOS活性抑制作用较高的噬菌体克隆,测序并合成其中具有一致序列的短肽。结果:得到具有较高表达量的目的蛋白,经His.Bind^TM柱亲和层析纯化后纯度大于95%,以纯化蛋白筛选Ph.D.-12^TM噬菌体库,经4轮筛选获得10株iNOS活性抑制作用较高的噬菌体克隆,测序发现其中5株序列完全相同,合成该12肽,初步研究表明其对iNOS表现为高浓度抑制,低浓度兴奋的作用,而对nNOS及eNOS则没有影响。结论:以iNOSFAD片段蛋白为靶蛋白筛选得到的克隆对iNOS活性具有特异性影响,可根据这些特征设计合成小分子前导药物,创造新的活性药物。  相似文献   
79.
目的 近年来产生了一些用于分析基因表达数据的聚类算法,却很少有关于评价聚类算法方法的研究。本研究的目的是尝试建立一个定量的评价基因表达数据聚类结果的方法。方法 本研究提供了一个系统的评价聚类结果的方法,利用我们提出的实验均方误差F值对几个常见的聚类算法进行比较。结果 利用F值对类质量的评价和利用已有的生物学知识对类进行分析的结果一致。结论 实验均方误差F值可以定量地评判用于基因表达数据的聚类算法。  相似文献   
80.
重组血红素加氧酶-2在大肠杆菌中表达与纯化方法的研究   总被引:1,自引:0,他引:1  
目的 确定重组血红素加氧酶 2在大肠杆菌中表达与纯化方法。方法 将已构建的血红素加氧酶 2(HO 2 )的重组质粒pMW1 72a HO 2转入大肠杆菌BL 2 1 ,分析不同温度及摇床转速对HO 2表达的影响 ,确定可溶性表达最佳条件。使用超声波、超速离心、分级盐析、分子筛层析等方法纯化HO 2。检测酶活性。结果 确定了HO 2可溶性表达最佳条件为 37℃ ,(85± 5 )r min ;确定了HO 2具体纯化路线。得到蛋白纯度为 95 .0 % ,纯化倍数为 2 .9倍 ,收得率为 4 0 .9%的活性HO 2蛋白。结论 获得了纯度高、具有活性的HO 2蛋白 ,为进一步进行HO 2结构与功能之间关系的研究提供了可行的纯化路线  相似文献   
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