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1.
骨髓干细胞诱导分化构建组织工程神经   总被引:4,自引:1,他引:3  
尚剑  袁绍辉  毕郑钢 《中国矫形外科杂志》2006,14(20):1574-1576,I0004
[目的]探讨组织工程化神经修复周围神经缺损的作用。[方法]以DMEM为培养基体外诱导人骨髓基质干细胞分化为雪旺细胞,与细胞外基质及可降解聚乳酸导管构建组织工程化神经;建立坐骨神经缺损10mm的Wistar大鼠动物模型,A组:经诱导骨髓基质干细胞分化雪旺细胞与天然细胞外基质(extra cellular matrix,ECM)凝胶及可降解聚乳酸导管构建组织工程化神经桥接神经缺损;B组:单纯将ECM凝胶注入可降解聚乳酸导管桥接神经缺损;C组:自体神经移植组。术后12周进行神经电生理检测、新生神经组织学观察和轴突计数等检测坐骨神经功能恢复情况。[结果]1.诱导后骨髓基质干细胞呈梭形、胞核大、周围有光晕、突起细长呈纵形排列,GAFP及S-100免疫组织化学染色阳性。动物模型各组经移植术后12周,再生神经已通过缺损区长至神经远端。A组、C组组织学及电生理检测指标均优于B组(PAB=0.021,PBC=0.001),A组与C组无显著性差异(PAC=0.065);A、B组聚乳酸导管降解吸收明显。[结论]骨髓基质干细胞在体外可诱导分化为雪旺氏细胞,利用其与细胞外基质及可降解聚乳酸导管构建组织工程化神经可以修复周围神经缺损。  相似文献   

2.
骨髓源神经干细胞修复大鼠周围神经缺损的实验研究   总被引:4,自引:1,他引:3  
目的: 探讨骨髓源神经干细胞用于组织工程化人工神经修复大鼠坐骨神经缺损的治疗效果。方法: 36只Wistar大鼠随机分为3组, 每组12只。A组: 将骨髓源神经干细胞与ECM凝胶混合, 种植于几丁糖神经导管中修复10mm坐骨神经缺损; B组: 仅将ECM凝胶种植于神经导管中; C组: 坐骨神经切下10mm, 翻转180°后缝合。16周后, 行大体观察、神经电生理检测、腓肠肌湿重测定、组织学染色, 免疫组化染色和轴突计数等检查。结果: A组的各项检测指标与C组相近, 明显优于B组, 差异显著(P<0. 05)。结论: 骨髓源神经干细胞可作为周围神经组织工程的种子细胞修复周围神经缺损。  相似文献   

3.
目的研究经大鼠脂肪源性干细胞(ADSCs)体外诱导分化的施万样细胞应用于组织工程化外周神经,修复大鼠坐骨神经缺损的效果。方法Wistar大鼠48只,体重200-250g,随机分成3组,每纽i6只,分别用下面3种不同的方法修复15mm坐骨神经缺损:DMEM组(支架内注射培养基)、诱导组(支架内注射施万样细胞)和自体神经移植组.通过足迹实验(坐骨神经功能指数测定)、神经电生理检测、胫前肌湿重比率测定进行功能检测;应用透射电镜、图像分析系统进行组织学观察。结果术后12周诱导组的SFI指数、神经传导速度、潜伏期、波幅以及胫前肌重量恢复、神经纤维数目、轴突直径、髓鞘厚厦好于DMEM组(P〈0.05),接近自体移植组。再生神经中标记细胞观察显示PKH-26标记的ADSCs,依然呈红色荧光。结论ADSCs诱导分化后的施万样细胞与去细胞同种异体神经两者构建的组织工程化神经能有效地修复大鼠坐骨神经缺损,其效果与自体神经移植相似:ADSCs经诱导后的细胞可以作为组织工程种子细胞新的来源。  相似文献   

4.
目的研究冻干去细胞异体神经修复大鼠坐骨神经缺损的效果。方法50只成年雌性DA大鼠随机分为5组,每组10只,分别用5种移植物桥接大鼠1.5cm坐骨神经缺损。A组:冻干去细胞异体神经种植类许旺细胞移植组;B组:冻干去细胞异体神经移植组;C组:去细胞异体神经移植组;D组:新鲜异体神经移植组;E组:自体神经移植组。术后4、24周通过大体观察、神经电生理、肌肉湿重及组织学指标评价各组修复神经缺损的效果。结果术后24周A、E组间差异无统计学意义(P〉0.05),A、E组的各项指标均优于B、C、D组(P〈0.05或P〈0.01)。结论冻干化学去细胞神经是良好的神经移植替代材料。  相似文献   

5.
目的探讨骨髓间充质干细胞(BMSC)作为组织工程化人工神经的种子细胞移植治疗外周神经损伤的效果。方法从成年大鼠的骨髓中分离培养得到BMSC,复合去细胞神经支架构建"组织工程化人工神经"。移植后分为BMSC+去细胞SD大鼠神经导管组(BMSC治疗组)和空细胞SD大鼠神经导管组(阴性对照组),每组各5只。比较两组大鼠术后2、4、8周损伤侧坐骨神经功能指数(SFI),术后8周损伤侧坐骨神经传导功能和小腿三头肌湿重恢复率等修复效果的指标。结果BMSC治疗组的坐骨神经修复术后2、4、8周损伤侧坐骨神经功能指数,术后8周损伤侧坐骨神经传导功能和小腿三头肌湿重恢复率均优于阴性对照组(均为P0.05)。结论 BMSC复合去细胞神经支架的组织工程化人工神经可有效促进神经再生和功能恢复。  相似文献   

6.
组织工程神经修复大鼠坐骨神经缺损的研究   总被引:1,自引:0,他引:1  
目的观察组织工程神经修复SD大鼠1.5cm长坐骨神经缺损的效果。方法用甘油处理10只SD大鼠2.0cm长坐骨神经,制备成同种异体脱细胞基质,备用。取SD乳鼠10只,分离坐骨神经,去神经外膜后,剪成小碎块,在DMEM中培养3周,扩增后的细胞鉴定、备用。3个月龄的SD雌性大鼠40只,单纯随机分成4个神经移植组(A、B、C、D),每组10只。A组:用扩增的雪旺细胞加同种异体脱细胞基质桥接,即组织工程化人工神经组。B组:用元雪旺细胞但具有内部支架结构的同种异体脱细胞基质桥接。C组:自体神经移植组。D组;空白对照组。术后12周,进行一般情况、小腿三头肌湿重、再生神经的组织学观察。结果完成对40只大鼠(每组10只)的实验评估。所有大鼠伤口瑚愈合,元死亡。A、B、C组大鼠足部元溃疡形成,D组7只足部有溃疡形成,所有组实验侧小腿三头肌较健侧萎缩,但以D组最明显。小腿三头肌湿重、神经电生理监测A组、C组差异无统计学意义(P〉O.05),A、C组与B、D组差异有统计学意义(P〈O.05),B组与D组差异有统计学意义(P〈0.05)。A组和C组的胫前肌中均能诱发出波幅明显的神经肌肉复合动作电位(CMAP),B组、D组中则仅录到波幅很低的CMAP。A组和C组再生轴突已通过移植段神经全长,远端肌肉轻度萎缩。B组部分通过移植段神经;D组不能通过移植段神经,6例形成神经瘤。结论组织工程人工神经可用来修复大鼠长段神经缺损。  相似文献   

7.
组织工程化人工神经实验研究   总被引:1,自引:0,他引:1  
目的:研究组织工程化人工神经修复大鼠2.5cm长坐骨神经缺损的效果。方法:21只2月龄Lewis 1w雌性大鼠随机分成三个神经移植组,每组7只。A组:种植同源雪旺细胞并具有内部支架结构的胶原神经管,即组织工程化人工神经。B组:无雪旺细胞但具有内部支架结构的胶原神经管。C组:自体神经移植体。术后六个月,进行系列神经电生理监测,神经肌肉组织学观察,S-100和神经微丝蛋白(Neurofilament)免疫组化染色,轴突计数等检查。结果:在A组和C组移植神经上均能诱发出波幅明显的神经肌肉复合动作电位(CMAP),再生轴突已通过移植神经全长,远端肌肉轻度萎缩。而B组中没有或仅记录到极小波幅的CMAP,移植神经远端结缔纤维组织增生,再生轴突罕见,所支配肌肉明显萎缩。结论:初步结果显示:组织工程化人工神经可用来修复大鼠长段神经缺损。  相似文献   

8.
目的 探讨脂肪干细胞(ADSCs)应用于组织工程化外周神经修复大鼠坐骨神经缺损的效果.方法 48只体重200~220 g的雌性F344大鼠随机分成6组,每组8只,分别用下面6种不同的实验组修复15 mm长坐骨神经缺损.A组:种植ADSCs的去细胞神经;B组:种植诱导ADSCs的去细胞神经;C组:种植许旺细胞(SCs)的去细胞神经;D组:去细胞神经;E组:自体神经移植;F组:空白对照.通过神经电生理检测、荧光金逆行示踪、组织学检测和坐骨神经功能指数测定评价各组修复神经缺损的效果.结果 术后12周,F组未见桥接物,A组和B组的神经电生理等各项指标均分别优于D组(P<0.05或P<0.01),与C组和E组间差异无统计学意义(P>0.05).结论 初步结果显示ADSCs及诱导后ADSCs作为种子细胞,与去细胞神经构建的组织工程化外周神经移植体,能够修复外周神经缺损.  相似文献   

9.
目的 探讨去细胞异种神经(acellular xenogeneic nerve,AXN)复合骨髓基质干细胞(bone marrow stem cells,BMSCs)修复周围神经缺损的效果.方法 体外培养大鼠BMSCs;取雌性Wistar大鼠60只,随机分为3组,每组20只,建立右坐骨神经10 mm缺损修复模型.A组:BMSCs与AXN复合修复神经缺损;B组:单纯AXN修复神经缺损;C组:自体神经移植组.术后4、12周依次进行干细胞的转归、移植免疫、神经电生理检测、新生神经组织学观察和小腿三头肌肌纤维横径等检测,判断坐骨神经功能恢复情况.结果 术后移植物内均可见细胞生长,A、C组细胞数目较多,排列整齐,只有A组S-100免疫组化染色阳性细胞内可见BrdU阳性表达,术后12周再生神经已通过远端缝合口.A组、C组组织学及电生理检测指标均优于B组(P<0.05),A组与C组差异无统计学意义(P>0.05).结论 BMSCs作为种子细胞可以在体内存活,并可分化为SCs,其与AXN复合构建组织工程神经修复神经缺损的效果接近于自体神经移植.  相似文献   

10.
组织工程化人工神经修复长段神经缺损实验的初步报告   总被引:18,自引:3,他引:15  
目的 研究组织化人工神经修复大鼠2.5cm长坐骨神经缺损的效果。方法 90只2个月月龄的Lewis1W雌性大鼠,按手术先后顺序随机分成3个神经移植组,每组30只。A组:用种植同源雪旺细胞并具有内部支架结构的胶原神经管桥接,即组织工程化人工神经组。B组:用无雪旺细胞但具有内部支架结构的胶原神经管桥接,即对照组。C组:自体神经移植组。术后6月,进行神经电生理监测,神经肌肉组织学观察;用S-100和神经微丝蛋白免疫组化染色后,行轴突计数等检测。结果 完成对21只大鼠(每组7只)的实验评估。从A组和C组的胫前肌中均能诱发出波幅明显的神经肌肉复合动作电位(CMAP),再生轴突已通过移植段神经全长,远端肌肉轻度萎缩。B组中则没有或仅记录到波幅很低的CMAP,移植神经远端结缔纤维组织增生,再生轴突罕见,所支配肌肉明显萎缩。结论 组织工程化人工神经可用来修复大鼠长段神经缺损。  相似文献   

11.
Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI2) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI2), TXB2 (stabile metabolite of thromboxane A2) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI2 release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB2 (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI2 release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A2, presumably contributing to hemodynamic stability within 30 min after MT.  相似文献   

12.
Don Dame 《Artificial organs》1996,20(5):613-617
Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.  相似文献   

13.
Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.  相似文献   

14.
Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.  相似文献   

15.
Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H2O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg−1 followed by 0.15 mg · kg−1 · h−1, n=8) or verapamil (0.1 mg · kg−1 followed by 0.3 mg · kg−1 · h−1, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.  相似文献   

16.
Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.  相似文献   

17.
Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.  相似文献   

18.
Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg?1 i. v. and 32 μg · kg?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg?1. The mean ED50s, calculated from dose-response curves, were 5.4 mg · kg?1, 3.9 μg · kg?1 and 0.4 mg · kg?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg?1 and 8 μg · kg?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.  相似文献   

19.
Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg?1 · min?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min?1 · m?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO2I) and oxygen consumption index (VO2I) were also significantly increased in the dopexamine group (DO2I: from 416±91 to 717±110 ml/m2 · m2; VO2I: from 98±25 to 157±22 ml/m2 · m2), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.  相似文献   

20.
A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.  相似文献   

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