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1.
目的探讨低能体外冲击波(ESW)和低剂量间歇人重组甲状旁腺素1-34(rhPTH1-34)对体外培养大鼠成骨细胞(ROBs)增殖和成骨分化的影响。方法分别用不同次数的低能ESW刺激、不同浓度及作用方式的rhPTH1-34刺激,以及ESW和低剂量间歇性rhPTH1-34刺激共同作用于ROBs后,用细胞计数、MTY和流式细胞术细胞周期分析检测ROBs的增殖,用酶标仪检测ALP活性,用免疫组化检测I型胶原表达来观察ROBs成骨分化。结果60~150次0.18mJ/mm^2 ESW刺激、间歇性rhPTH1-34(1×10^-11和1×10^-10 mol/L)刺激以及ESW+间歇性rhPTH1-34(1×10^-11mol/L)刺激均可显著促进体外培养ROBs细胞增殖和成骨分化(与对照组比较,P〈0.05);其中60~150次ESW刺激+间歇性rhPTH1-34(1×10^-11 mol/L)刺激各组作用最强。结论适当的ESW应力刺激和低剂量间歇性rhPTH1-34刺激可显著促进体外培养ROBs细胞增殖和成骨分化,两者联合应用作用最强。  相似文献   

2.
目的 联合甲状旁腺激素(rhPTH 1-34)和普萘洛尔(PRO)处理体外培养的人松质骨源性成骨细胞(HOB),观察其对人成骨细胞增殖及骨保护素(OPO)和核因子KB受体活化因子配体(RANKL )基因表达的影响,探讨其对骨代谢影响的可能机制。方法 (1)以成人骼骨和股骨颈部松质骨为原料,分离培养原代人成骨细胞并对其鉴定。(2)以人成骨细胞为体外实验模型,固定浓度rhPTH1- 34 (50 ng/ml)和不同浓度PRO(0. 1μM,1μM,10μM)分别及联合刺激体外培养的人成骨细胞72 h后,采用CCK-8法检测细胞增殖能力,用实时荧光定量PCR法检测成骨细胞OPG和RANKL基因的表达。结果 rhPTH1-34和PRO单独给药均可促进成骨细胞增殖(P <0.05),在PRO 10μM时成骨细胞OPG基因的表达量增加(P<0.05),且大于RANKL基因的表达量;相反,联合rhPTH 1-34和PRO给药抑制成骨细胞增殖(P<0.05),并抑制成骨细胞OPG和RANKL基因的表达(P<0.05),且随着PRO浓度的增加,OPG和RANKL基因表达均呈下降趋势。结论 rhPTH1- 34和PRO单独给药均可促进成骨细胞增殖,而两者联合给药后却抑制了成骨细胞的增殖,可能是通过调控OPG和RANKL基因的表达来实现的。  相似文献   

3.
目的 研究重组人甲状旁腺激素1-34(rhPTH1-34)对成骨细胞增殖及BMP-7、BMP-9基因表达的影响.方法 通过不同剂量的重组人甲状旁腺素(rhPTH1-34)(0、10-11、10-10、10-9、10-8、10-7mol/L)间歇性(24 h/周期,前12 h rhPTH1-34干预)刺激体外培养的成骨细胞,用噻唑蓝(MTT)法检测细胞的增殖能力,RT-PCR法检测成骨细胞BMP-7、BMP-9基因的表达.结果 间歇性小剂量rhPTH1-34可明显促进成骨细胞的增殖能力及增强BMP-7、BMP-9基因的表达.结论 间歇性小剂量rhPTH1-34可促进成骨细胞增殖,可能与BMP-7、BMP-9基因表达相关.  相似文献   

4.
目的:通过构建乳鼠颅盖骨成骨细胞分离培养与鉴定方法,研究胰岛素样生长因子-1(Insulin-like growth factor-1,IGF-1)及IGF-1联合重组人甲状旁腺激素1-34(recombinant human parathyroid hormone 1-34,rhPTH1-34)对成骨细胞增殖及I型胶原蛋白mRNA表达的影响。方法培养乳鼠成骨细胞,并观察其形态及功能,以原代培养乳鼠成骨细胞为实验模型,分空白组、PTH组、IGF-1组及不同浓度IGF-1作用的PTH介导的成骨细胞组(0、10、50、100 ng/L)。通过不同剂量的胰岛素样生长因子-1(0、10、50、100 ng/L)联合10-9 mol/L重组人甲状旁腺素刺激体外培养的成骨细胞,用噻唑蓝( MTT)法检测细胞的增殖能力,RT-PCR法检测成骨细胞I型胶原蛋白mRNA的表达。结果 PTH和IGF-1均可促进成骨细胞增殖;IGF-1联合PTH可以促进成骨细胞增殖,且具有剂量依赖性。 PTH联合IGF-1使成骨细胞增殖能力增强、I型胶原蛋白mRNA表达增强。 IGF-1可以促进成骨细胞I型胶原蛋白mRNA的表达,且具有剂量依赖性。 IGF-1可以促进成骨细胞I型胶原蛋白mRNA的表达,且具有剂量依赖性。结论 PTH与IGF-1均可刺激成骨细胞增殖和分化,IGF-1可促进PTH对成骨细胞的分化、增殖。两者合用其作用增强,有协同促进作用。  相似文献   

5.
目的观察间歇给予重组人甲状旁腺激素(1-34)[rhPTH(1-34)]对体外成骨细胞增殖、Ⅰ型胶原蛋白(Collagen Ⅰ)及Osterix mRNA表达的影响,初步探讨rhPTH(1-34)对体外成骨细胞的作用机制。方法体外培养新生大鼠成骨细胞,间歇循环给予0、10-11、10-10、10-9、10-8、10-7M rhPTH(1-34)干预,(24 h为一循环,前12h给药),共2次,用MTT法检测细胞的增殖;RT-PCR法半定量测定成骨细胞Collagen Ⅰ、Osterix mRNA的表达。结果显示rhPTH(1-34)可明显促进成骨细胞的增殖(P<0.05),促进成骨细胞Collagen Ⅰ和Osterix mRNA表达(P<0.05),10-9 M增殖、表达最明显,呈剂量依赖关系。结论 rhPTH(1-34)可促进成骨细胞的增殖、分化,可能是通过Collagen Ⅰ和Osterix mRNA表达来调节。  相似文献   

6.
目的 观察间歇给予重组人甲状旁腺激素(1-34)[rhPTH(1-34)]对体外成骨细胞增殖、I型胶原蛋白(CoHagen I)及Osterix mRNA表达的影响,初步探讨rhPTH(1-34)对体外成骨细胞的作用机制.方法 体外培养新生大鼠成骨细胞,间歇循环给予0、10-11、10-10、10-9、10-8、10-7 M rhPTH(1-34)干预,(24 h为一循环,前12h给药),共2次,用MTT法检测细胞的增殖;RT-PCR法半定量测定成骨细胞Collagen I、Ostefix mRNA的表达.结果 显示rhPTH(1-34)可明显促进成骨细胞的增殖(P<0.05),促进成骨细胞Collagen I和Ostefix mRNA表达(P<0.05),101-9 M增殖、表达最明显,呈剂量依赖关系.结论 rhPTH(1-34)可促进成骨细胞的增殖、分化,可能是通过Collagen I和Ostefix mRNA表达来调节.  相似文献   

7.
目的 观察间歇给予重组人甲状旁腺激素(1-34)[rhPTH(1-34)]对体外成骨细胞增殖、I型胶原蛋白(CoHagen I)及Osterix mRNA表达的影响,初步探讨rhPTH(1-34)对体外成骨细胞的作用机制.方法 体外培养新生大鼠成骨细胞,间歇循环给予0、10-11、10-10、10-9、10-8、10-7 M rhPTH(1-34)干预,(24 h为一循环,前12h给药),共2次,用MTT法检测细胞的增殖;RT-PCR法半定量测定成骨细胞Collagen I、Ostefix mRNA的表达.结果 显示rhPTH(1-34)可明显促进成骨细胞的增殖(P<0.05),促进成骨细胞Collagen I和Ostefix mRNA表达(P<0.05),101-9 M增殖、表达最明显,呈剂量依赖关系.结论 rhPTH(1-34)可促进成骨细胞的增殖、分化,可能是通过Collagen I和Ostefix mRNA表达来调节.  相似文献   

8.
目的 比较间歇皮下注射人甲状旁腺激素不同片段(hPTH1-34)及(hPTH1-84)对完整雌性(Non-OVX)大鼠和去卵巢(OVX)大鼠股骨及腰椎1-4骨矿物含量(BMC)和骨密度(BMD)的影响。方法 Wistar雌性大鼠176只,分为hPTH1-34和hPTH1-84两大组(各80只及96只),每大组及各自分4组(每组各20只或24只),分别为:两组安慰剂组(未切卵巢及切卵巢)用安慰剂(PBS)进行皮下注射,每周3次,共2周;两组治疗组(未切卵巢及切卵巢)用hPTH1-34或hPTH1-84,皮下注射,每周3次,共2周。结果 1.卵巢切除术后3个月大鼠股骨及腰椎1-4BMC和BMD明显下降;2.两种片段的甲状旁腺激素(hPTH1-34及pPTH1-84)间歇注射均能使Non-OVX大鼠和OVX大鼠股骨及腰椎1-4BMC和BMD较相应对照组明显升高;且腰椎1-4较股骨的BMC和BMD升高更明显;3.OVX大鼠治疗后股骨与腰椎1-4BMC和BMD的升高率较Non-OVX大鼠更明显;OVX大鼠在治疗后股骨及腰椎骨量能恢复到去卵巢前水平;4.hPTH1-34较hPTH1-84更明显的使完整大鼠和OVX大鼠股骨BMC和BMD升高。结论 间歇皮下注射人甲状旁腺激素对大鼠股骨及腰椎骨量均有增高作用,尤其对腰椎的骨量以及对去卵巢大鼠骨量升高作用更明显;hPTH1-34片段对大鼠股骨骨量的增高作用强于hPTH1-84片段。  相似文献   

9.
持续给予hPTH1-34对体外成骨细胞增殖与分化的影响   总被引:1,自引:1,他引:0       下载免费PDF全文
目的研究持续给予人甲状旁腺激素(human parathyroid hormone,hPTH)1-34对体外培养成骨细胞增殖与分化的干预作用。方法体外培养乳鼠成骨细胞,将细胞分为空白培养液对照组和10^-6、10^-7、10^-8mol·L^-1hPTH(1-34)3个不同剂量的给药组。每48h换1次液,换液时采用MTT法进行细胞增殖测定,同时检测细胞裂解液中的碱性磷酸酶(alkaline phosphatase,ALP)和骨钙素(bone gla protein,BGP)的水平,持续培养6d。结果持续给予hPTH1-34作用48h后,各给药组的MTT均明显高于对照组且各给药组间差异均有显著性(P〈0.05),至第6天时各给药组则均明显低于对照组(P〈0.05)。ALP和BGP测定结果显示持续给予hPTH1-34作用48h后,10^-6mol·L^-1PTH给药组的BGP含量明显高于对照组(P〈0.01),其余各组ALP及BGP含量与对照组比较差异虽无显著性,但均值高于对照组,至第6天各给药组均明显低于对照组(P〈0.05)。结论持续给予hPTH(1-34)对体外培养成骨细胞增殖与分化的影响与作用的时间和给药浓度密切相关。短期持续用药有促进作用,并且在10^-6-10^-8mol·L^-1浓度范围内呈剂量依赖性;长期持续用药抑制成骨细胞的增殖与分化,给药浓度越高抑制作用越强。  相似文献   

10.
目的探讨脱氢表雄酮(dehydroepiandrosterone,DHEA)对离体大鼠成骨细胞和IL-1β的影响。方法体外分离培养大鼠成骨细胞,取传一代细胞,分别给予10^-5mmoL/L、10^-7mmoL/L、10^-9mmol/LDHEA培养72h,以10^-8mmoL/L雌二醇(estradiol,E2)为阳性对照,另设空白对照组。碱性磷酸酶(alkaline phosphatase,ALP)染色鉴定成骨细胞,MTT法检测成骨细胞的增殖能力,PNPP法测定ALP活性。ELISA法测定不同浓度DHEA培养液中IL-1β的水平。结果不同浓度DHEA组成骨细胞增殖能力和ALP的活性均有上升,其中以10^-7mmoL/LDHEA组最显著(P〈0.01),其作用和E2相似(P〉0.05);10^-9mmoL/LDHEA组单位细胞数的ALP活性高于空白对照组(P〈0.05)。不同浓度的DHEA组IL-1β呈下降趋势,成骨细胞增殖能力及ALP活性和IL-1β成负相关。结论DHEA在体外促进大鼠成骨细胞生长和增殖,提高ALP活性,其作用可能和抑制IL-1β有关。  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.
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   

13.
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   

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: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.  相似文献   

16.
Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.  相似文献   

17.
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   

18.
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   

19.
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   

20.
Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.  相似文献   

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