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991.
严重烧伤休克期切痂对休克复苏影响的实验研究 总被引:10,自引:1,他引:9
目的 探讨烧伤休克期切痂的可行性及其对休克复苏的影响。方法 采用40%TBSAⅢ度烫伤犬模型,随机分为切痂组(E组)和非切痂组(C组)。伤后1h按Parkland公式补给平衡盐溶液,E组动物伤后3h切痂。分别于伤前及伤后30min和3、6、12、24、48h检测血流动力学、血液流变学业、氧代及血浆氧自由基变化。结果 烧伤后30min,CO明显下降,全血粘度、血浆粘度、红细胞聚积指数和血乳酸含量明显增加,切痂后,E组动物上述指标较C组明显改善。结论 休克期切痂能较早地纠正血流动力学、血液流变学紊乱及氧代谢障碍,减轻氧自由损伤,有利于烧伤休克的复苏。 相似文献
992.
乳腺癌组织中—p—MAPK活化对c—fos和c—jun的激活作用 总被引:2,自引:0,他引:2
OBJECTIVE: This paper was to investigate the relationship between expression of p-MAPK and oncogenesis of breast cancer. METHODS: Immunohistochemical technique was used to detect the expression of p-MAPK and c-fos and c-jun proteins in 68 cases of breast cancers, 42 cases of pericarcinomatous tissues and 7 cases of normal breast tissues. RESULTS: Positive stainings of p-MAPK, c-fos, and c-jun were localized in cancer cell nuclei. The positive rates of p-MAPK, c-fos, and c-jun were 86.8% (59/68), 82.4% (56/68), and 77.9% (53/68), respectively, which were much higher than that in pericarcinomatous tissues (P < 0.01). Of some cases, p-MAPK positive staining was also found in the nuclei of the fibroblastic and angioendothelial cells of cancer stroma. CONCLUSION: Activated or overexpressive MAPK activates the immediately-early oncogenes(c-fos, c-jun), which might play an important role in carcinogenesis of breast cancer and be an early event of oncogenesis of breast cancer. 相似文献
993.
肝细胞癌发生中丙型肝炎病毒NS3蛋白对诱导型一氧化氮合酶表达的影响 总被引:2,自引:0,他引:2
OBJECTIVE: To investigate hepatocarcinogenesis by detecting the effect of HCV NS3 protein on expression of inducible nitric oxide synthase (iNOS) mRNA in hepatocellular carcinoma (HCC) and pericarcinomatous liver tissues(PCLT). METHODS: The expression of HCV NS3 protein and iNOSmRNA was detected by immunohistochemical technique (SP method) and in situ hybridization in specimens of HCC and PCLT from 52 patients with HBV(-). The relationship between the positive rate and the signal strength was tested statistically. RESULTS: The positive rate of HCV NS3 protein in HCC was lower (46.2% vs. 67.3%), and signal strength was weaker than those in PCLT. The signal strength of HCV NS3 protein was correlated with the degree of carcinomatous cells differentiation in HCC (P < 0.01). The positive rates (80.8% and 90.4%) of iNOSmRNA in HCC and PCLT had no statistical difference. Signal intensity of iNOSmRNA in HCC was weaker than that in PCLT. The higher HCVNS3 protein expression level was, the stronger iNOSmRNA signals in PCLT (P < 0.01). In particular, the localization and patterns of HCV NS3 protein were much similar to those of iNOSmRNA in the PCLT of some patients. CONCLUSIONS: HCV NS3 protein may exert its hepatocarcinogenic effect in the early stage on host cells by increasing product of nitric oxide, which may bring about transformation of hepatocytes. 相似文献
994.
995.
大鼠脑损伤后GABA及其受体GABAAR的变化 总被引:1,自引:0,他引:1
目的 探讨GABA及其受体GABAAR在创伤性脑损伤(TBI)后的变化规律及其在继发性脑损害中的作用。方法 用大鼠颅脑打击伤动物模型、免疫组织化学方法,观察了致伤后不同时相大鼠伤侧及对侧皮层、海马的GABA及GABAARα2阳性神经元的表达变化。结果 致伤后伤侧皮层GABA/GABAARα1阳性神经元逐渐减少,12h降至最低,对侧皮层无改变;伤侧海马及对侧海马GABA阳性神经元逐渐减少,12h降至最低;伤侧海马GABAARα1的改变与GABA的改变一致,对侧海马无改变。结论 TBI后脑内抑制性神经递质GABA及其受体GABAAR的表达下调也可能是继发性脑损害的重要因素之一。 相似文献
996.
内毒素血症小鼠巨噬细胞膜脂改变对CD14表达及TNFα分泌的影响 总被引:3,自引:1,他引:2
目的 以小鼠内毒素血症为模型,研究小鼠腹腔巨噬细胞膜脂改变,及其对受体CD14表达及血浆TNFα产生的影响。方法 48只小鼠分为3组。①对照线(n=8);②内毒素血症组:小鼠尾静脉注射LPS,200μg/只,分1、3、5、8 4个观察时相点,每个时相点8只动物;③脂质体预处理组(n=8):小鼠腹腔注射卵磷脂脂质体1ml(1mg/ml),18h后尾静脉注射LPS,200μg/只,5h后观察巨噬细胞膜脂成分、膜流动性及CD14阳性率、血浆中TNFα含量的变化。结果 LPS刺激下,巨噬细胞主要膜脂成分降解,细胞膜荧光偏振度、微粘度和分子排列有序系数增加,膜流动性显著降低;CD14阳性率增加,5h达高峰,8h降至正常水平;TNFα含量显著升高,3h达高峰,8h降至正常水平。磷脂脂质体预处理后,膜损伤减轻,CD14阳性率及TNFα含量均明显降低。结论 内毒素血症小鼠腹腔巨噬细胞膜磷脂降解,细胞膜从相对比较流动变为相对固化,这可能是膜受体CD14阳性率增加,TNFα产生增多的重要原因。脂质体预处理能修复膜损伤,减少膜CD14表达,减轻炎症反应。 相似文献
997.
14例中小肝癌射频消融治疗的近期疗效分析 总被引:4,自引:0,他引:4
目的 探讨射频消融治疗中小肝癌(直径≤5cm)的疗效。方法 应用可扩张的集束电极对14例中小肝癌共18个病灶进行射频消融治疗,观察其治疗过程中的反应、治疗时间、治疗次数、影像学表现以及治疗前后的肝穿刺病理结果,并随访观察其复发和生存情况等。结果 14例中小肝癌的治疗次数为1~2次,平均治疗时间为50min;治疗后的反应包括伤口自限性出血、转氨酶升高、肝区疼痛及发热等;治疗后对9例病灶行多点穿刺活检均为凝固性坏死及纤维组织;CT扫描显示治疗后病灶扩大,但无明显强化,3个月后病灶开始缩小,病灶完全坏死率为93%;经12~18个月的随访,全部病例存活。结论 射频消融治疗中小肝癌具有创伤小、并发症少、效果确切等优点,可望成为治疗中小肝癌的有效方法之一。 相似文献
998.
分析 5 2例PBMV术中 2 2例老年患者的手术情况 ,探讨老年人PBMV术的特点及其对策。手术结果表明 :老年组术后出现二尖瓣返流机会较非老年组多 ,房颤转窦性心律及心功能改善非老年组较老年组明显。说明与老年患者的病程长 ,瓣膜损害程度重 ,血流动力学及心功能障碍显著有关。提示在老年患者中开展PBMV更应掌握适应证 ,做好充分的术前准备。 相似文献
999.
Objective. To review our preliminary experience and evaluate our early results of a combined intraopemtive iliac angioplasty and stenting with infrainguinal revascularization in multilevel atherosclerotic occlusive disease. Methods. From July 1999 to April 2000, intraoperative iliac angiOplasty and stenting combined with simultaneous femoro-pepliteal bypass were pedormed on 12 lower extremities of 10 patients suffering from multilevel athemsclemtic occlusive disease. There were 8 men and 2 women, average 72 years. The indicationsf or procedures included disabling claudication in 3 and rest pain in 7 patients. Results. Eleven iliac angioplasty and stem procedures combined with simultaneous 9 femoro-popliteal by-pass and 3 femoro-femoral-popliteal bypass were performed in 12 limbs of 10 patients. Angioplasty and stem placement was technically successful in all patients. One contralateral femoral-popliteal bypass was failure after femoro-femoral-popliteal bypass. There were no additional instances of procedural or postoperative morbidity or mortality. Mean follow-up was 5 months (range 1 -10 months). During the follow-up period, one femoro-infrapoplitealgraft became occluded after 7 months and above-knee amputation was required. The cumulative primary patencyrate of stented iliac arteries, femoro-femoral bypass grafts and femoro-popliteal bypass grafts were 100% (11/11), 100% (3/3) and 90. 9% (10/11) in the follow-up period, respectivdy. The amputation rate was 8. 3%(1/12). Conclusions. Intraoperative iliac artery PTA and stent placement can be safely and effectively pedormed simultaneously with infrainguinal revascularization for multilevel atherosclerotic occlusive disease by skilled vascular surgeon, using a portable C ann fluoroscopy in the operating room. Furthermore, iliac artery PTA and stenting was valuable adjunct to distal bypass either to improve inflow and outflow, or to reduce the extent of traditionalsurgical intervention, and also, any angioplasty and stenting-related complications can be immediately corrected as well. 相似文献
1000.
Objective. To explore the relationship between human parvovirus B19 (HPV B19) infection and aplastic anemia (AA) and to investigate the role of HPV B19 in the occurrence of AA. Methods. The presence of HPV B19 DNA was detected in the peripheral blood samples of 60 patients with AA (children 38 and adults 22) by nested polymerase chain reaction (PCR) assay, and 30 healthy persons were selected as control. Results. Sixteen (26. 7 % ) of 60 AA cases were HPV B19 DNA positive, while all the samples in the control group were negative for HPV B19 (P = 0. 000914). Among the case group, the positive rates of HPV B19 DNA were21.4% (6 /28), 30.0% (3 / 10), 20.0% (1 /5) and 35.3% (6 / 17) in children acute AA (AAA), children chronic AA (CAA), adults AAA and adults CAA patients respectively, which were significant-ly higher than that in the control group, Furthermore, there was no remarkable difference between children AA and adults AA in the 16 HPV B19 DNA positive patients; neither was there between AAA and CAA. Conclusions. HPV B19 infection is not only correlated with the occurrence of children AAA and CAA, but also with adults AAA and CAA, and might be an important viral cause for AA in humans. 相似文献