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1.
目的:探讨骨髓间质干细胞对MPP+损伤的离体黑质-纹状体脑片多巴胺能神经元的保护作用。〖HTH〗方法:建立MPP+损伤的离体脑片模型。取成年大鼠骨髓,培养、分离和纯化骨髓间质干细胞。将骨髓间质干细胞与离体脑片联合培养,通过免疫组化和电镜等方法观察骨髓间质干细胞对联合培养的MPP+损伤脑片的保护作用。〖HTH〗结果: MPP+可造成离体黑质-纹状体脑片的细胞大量死亡,但与MSCs联合培养7 d,脑片周围神经轴突生长增多,脑片中的细胞死亡减少、超微结构损伤减轻、表达TH阳性的细胞数目增多(P<0.05)。〖HTH〗结论:MSCs在体外能促进受损的黑质-纹状体脑片多巴胺能神经元存活,可望用于帕金森病的移植治疗。 相似文献
2.
目的:探讨粒细胞集落刺激因子(G-CSF)对1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)所致小鼠帕金森病(PD)模型中脑黑质致密部(SNpc)及纹状体(STR)多巴胺(DA)能神经元的影响。方法:正常健康雄性C57BL/6J小鼠随机分为对照组、MPTP组及MPTP+G-CSF组,采用腹腔注射MPTP法制作小鼠PD模型,MPTP+G-CSF组于最后一次MPTP注射后再腹腔注射G-CSF。爬杆实验观察小鼠的行为学改变;尼氏染色技术观察各组小鼠黑质致密部神经元数量及形态学变化;免疫组织化学法检测酪氨酸羟化酶(TH)在各组小鼠中脑黑质致密部及纹状体的表达; Western Blot法检测各组小鼠中脑TH蛋白的表达量。结果:与对照组相比,MPTP组小鼠较对照组爬杆用时显著延长(P 0. 05),尼氏染色显示黑质致密部神经元数量显著减少(P 0. 05),黑质致密部、纹状体TH表达量显著减少(P 0. 05); MPTP+G-CSF组较MPTP组爬杆用时显著缩短(P 0. 05),神经元丢失减少(P 0. 05),神经元形态较完整;与MPTP组比较,MPTP+G-CSF组黑质致密部、纹状体TH表达水平显著增高(P 0. 05)。结论:G-CSF能够改善PD小鼠运动功能,减少黑质致密部多巴胺能神经元丢失,增加TH表达水平。 相似文献
3.
黑质多巴胺触液神经元 总被引:2,自引:0,他引:2
将30% HRP 8—10μl或3%碘化丙啶(PI)3μl分别注入两组动物单侧侧脑室内,48小时后将鼠处死,检查中脑切片。发现双侧黑质均司见HRP标记细胞群,但以同侧为主。标记范围以中脑中上部为多。标记细胞主要分布在黑质致密带内侧部,网状带中仅少数散在。注射PI例所见类同,但标记细胞远较HRP标记细胞为多。TH免疫组化法发现黑质DA神经元投射纤维分散布于尾壳核,并见TH阳性投射纤维在室管膜上皮细胞的深面形成密集的膨大,个别地区还见阳性终末突入侧脑室。另外,在接受胚中脑黑质移植存活良好的受体鼠纹状体中,发现少数移植存活的TH阳性黑质DA神经元胞体或其突起伸入侧脑室室管膜上皮细胞间甚或突入室腔。实验表明部分黑质多巴胺神经元系触液神经元,提示可能直接释放DA入脑脊液。当胚黑质细胞被移植入受体脑纹状体后,部分黑质DA神经元重演其发育的规律,将其突起或胞体伸入室管膜上皮细胞间或突入侧脑室,以代偿其原有的功能。 相似文献
4.
目的:探索中脑黑质多巴胺神经元对适当剂量鱼藤酮毒性损伤是否具有特殊敏感性。方法:采用颈背部皮下注射鱼藤酮的方法建立大鼠中脑黑质多巴胺神经元损伤模型,进行中脑黑质和纹状体酪氨酸羟化酶(TH)免疫组织化学染色加尼氏染色;同时通过HE染色及尼氏染色方法分别观察心、肝、脾、肾等重要胸腹腔脏器及海马、顶叶皮质的形态学变化。结果:中脑黑质TH免疫染色和尼氏染色结果显示组间中脑黑质致密区以外部位尼氏小体数目无差异;大脑顶叶皮质和海马尼氏染色及胸腹腔重要脏器HE染色结果表明各组大鼠均未出现相应部位损伤。结论:低剂量颈部皮下注射鱼藤酮能选择性诱导中脑黑质多巴胺神经元损伤,说明中脑黑质多巴胺神经元对鱼藤酮具有高度敏感性。 相似文献
5.
目的:观察胚胎神经于细胞脑内移植后的存活及生长分化状况。方法:从孕11d(E11d)大鼠胚胎神经管获取神经上皮细胞,经神经巢蛋白(nestin)染色鉴定干细胞;同时植入同种大鼠黑质内。于移植后7d、14d取脑,用神经元特异烯醇化酶(NSE)、酪氨酸羟化酶(TH)免疫组化方法检测移植细胞的存活及分化状况。结果:E11d神经管上皮细胞多数呈nestin染色阳性,黑质内移植后增殖形成细胞团并随时间延长而增大。免疫组化染色显示移植细胞团内有NSE及TH免疫阳性细胞。结论:胚胎神经上皮细胞多数为神经干细胞,黑质内移植后可以存活并分化为多巴胺能神经元。 相似文献
6.
目的 探讨尼古丁对帕金森病(PD)大鼠黑质多巴胺能神经元变性的影响及其机制. 方法 45只大鼠随机分为PBS对照组(CON)、生理盐水+ 脂多糖(NS)组、尼古丁+脂多糖(NIC)组,每组15只.黑质内立体定向注射脂多糖(LPS)或PBS后24h,免疫印迹法检测黑质诱导性一氧化氮合酶(iNOS)蛋白表达变化;黑质注射药物后14d,采用免疫组织化学法观察大鼠黑质酪氨酸羟化酶(TH)阳性神经元数量及OX-42阳性细胞形态学变化,RT-PCR及免疫印迹检测黑质TH mRNA及TH蛋白的表达水平. 结果 与CON组相比,NS组大鼠黑质iNOS表达明显增多,TH阳性神经元、TH mRNA及TH蛋白明显减少,小胶质细胞大多呈胞体大突起短粗的形态;NIC组黑质iNOS表达明显少于NS组,黑质TH阳性神经元、TH mRNA及TH蛋白表达较NS组明显增多,大部分小胶质细胞呈胞体小,突起细长的形态. 结论 尼古丁可以减轻LPS介导的多巴胺能神经元变性,对多巴胺能神经元有保护作用,其保护机制与抑制小胶质细胞激活、减少iNOS的表达有关. 相似文献
7.
为探讨尼古丁对多巴胺能神经元的保护作用,本研究采用尼古丁(0.25mg/kg)预处理C57BL/6J小鼠,再给予1-甲基-2-乙基-1,2,3,6-四氢吡啶(MPTP;20mg/kg)诱导Parkinson病(PD)小鼠模型。通过行为学检测和中脑黑质致密部(SNc)的酪氨酸羟化酶(TH)以及OX-42的免疫组织化学染色,观察了尼古丁对PD小鼠的行为以及黑质多巴胺能神经元和小胶质细胞的影响。结果显示:经尼古丁预处理可以明显减轻PD小鼠的行为障碍,增加TH免疫阳性的多巴胺能神经元的数量,并且可以抑制SNc内小胶质细胞的增生。本研究结果提示,尼古丁可保护多巴胺能神经元,而抑制小胶质细胞的增生可能是其作用机制。 相似文献
8.
目的 后存活24周、48周和生理盐水注射后存活48周.上述5只动物于存活前0周、8周、16周,向右侧黑质分3次注射脂多糖或生理盐水.术后用免疫组织化学染色及高效液相色谱法观察黑质TH阳性神经元的变化和纹状体神经递质含量的改变. 结果 急性实验组注射侧与对照侧TH表达量无明显差异,但注射侧可见小胶质细胞活化,人类白细胞DR抗原表达量上调并有大量肿瘤坏死因子α、白介素1β、环氧化酶2(COX-2)生成.慢性实验组单侧黑质脂多糖注射24周和48周后,各个动物注射侧黑质阳性神经元数量以及纹状体神经递质含量有不同程度的减少,而生理盐水注射动物无变化. 结论 脂多糖注射后在1周内可引起黑质剧烈的炎症反应,但这种病理过程并不伴随大量多巴胺能神经元死亡.随病程的发展,炎症反应能引起恒河猴黑质多巴胺能神经元慢性进行性的损伤.该病理过程较好模拟了帕金森病的发病特点. 相似文献
9.
目的研究帕金森病(Park inson’s d isease,PD)小鼠黑质和纹状体多巴胺(dopam inergic,DA)能神经元数量和超微结构的变化及多聚ADP-核糖聚合酶(poly(ADP-ribose)polym erase,PARP)抑制剂PJ34的干预作用。方法采用1-甲基-4-苯-1,2,3,6-四氢吡啶(1-m ethyl-4-phenyl-1,2,3,6-tetrahydropyrid ine,MPTP)制备PD小鼠模型,并用PJ34进行干预,2h、24h、72h进行酪氨酸羟化酶(tyrosine hydroxylase,TH)免疫组化染色观察DA能神经元数量,透射电镜观察超微结构改变。结果与正常对照小鼠比较,PD小鼠黑质TH阳性神经元进行性减少,核膜皱缩,染色质凝聚成块并有边聚现象;纹状体TH阳性神经纤维稀疏,突触数量减少。与PD小鼠比较,PJ34干预组黑质TH阳性神经元明显增多,纹状体TH阳性神经纤维密度增加(P<0.01),细胞形态比模型组明显改善。结论PARP的活性改变在PD的发病过程中发挥重要作用,PARP抑制剂对DA能神经元有保护作用。 相似文献
10.
目的研究成年大鼠帕金森病(PD)时,黑质内是否存在神经祖细胞,并进一步观察其增殖和分化的情况.方法成年大鼠纹状体内立体定位注射6-羟多巴胺(6-OHDA),并作行为学分析,筛选PD动物模型.取不同存活时间鼠脑黑质节段,用免疫组织化学染色方法,以抗巢蛋白(Nestin)抗体、抗增殖细胞核抗原(PCNA)抗体、抗Ⅲ型β-微管蛋白(Tuj1)抗体、抗酪氨酸羟化酶(TH)抗体分别显示神经祖细胞、分裂细胞、神经元前体细胞和多巴胺(DA)能神经元.光镜观察并细胞计数,统计学分析.结果PD模型大鼠右侧黑质内可见:1.Nestin反应阳性细胞:注射6-OHDA后第10 d,黑质致密部可见少量Nestin阳性细胞;第14 d时,出现大量Nestin阳性细胞;第17 d时开始减少;第21 d几乎检测不到.2.抗PCNA反应阳性细胞:注射6-OHDA后第7 d即可检测到较弱的PCNA阳性细胞;第14 d出现大量PCNA阳性细胞;至21 d开始减少、减弱;28 d时则检测到少量阳性细胞.3.抗Tuj1反应阳性细胞:注射后第10 d,开始出现少量Tuj1阳性细胞;第14 d出现大量Tuj1阳性细胞;第17 d开始减少,第21 d几乎检测不到.4.抗TH反应阳性神经元:注射6-OHDA后第7 d,黑质致密部抗TH反应阳性神经元数量显著少于对照组,且随注射时间延长而逐渐下降.结论成年大鼠纹状体内注射6-OHDA致黑质多巴胺能神经元变性、死亡,能诱导黑质内神经祖细胞在一段时期内大量增殖并向神经细胞方向分化(不包括多巴胺能神经元). 相似文献
11.
Myoung-Chul Yoon Mal-Soon Shin Tea-Soo Kim Bo-Kyun Kim Il-Gyu Ko Yun-Hee Sung Sung-Eun Kim Hee-Hyuk Lee Young-Pyo Kim Chang-Ju Kim 《Neuroscience letters》2007
In Parkinson's disease, the progressive loss of dopaminergic neurons in the pars compacta of the substantia nigra leads to debilitating motor dysfunction. In the present study, we investigated the effects of treadmill exercise on the dopaminergic neuronal cell death in the substantia nigra and on the dopaminergic fiber loss in the striatum of Parkinson's rats. Parkinson's rats were made by injecting 6-hydroxydopamine into the striatum with using a stereotaxic instrument. The rats in the exercise groups were put on the treadmill to run for 30 min once a day for 14 consecutive days after 6-hydroxydopamine administration into the striatum. Two weeks after the intrastriatal injection of 6-hydroxydopamine, the rats without treadmill exercise displayed rotational asymmetry following injection of apomorphine (0.5 mg/kg, s.c.). In contrast, the rats undergoing treadmill exercise showed a significant reduction of rotational asymmetry. Analysis via immunohistochemistry for the tyrosine hydroxylase expression revealed a substantial loss of cell bodies in the substantia nigra and their projected fibers in the striatum ipsilateral to the lesion following 6-hydroxydapamine injection into the striatum. However, treadmill running enhanced the survival of dopaminergic neurons in the substantia nigra and also their fibers projecting into the striatum. The results of the present study show that treadmill exercise may provide therapeutic value for the treatment of Parkinson's disease patients. 相似文献
12.
The effects of i.c.v. infused platelet-derived growth factor and brain-derived neurotrophic factor on cell genesis, as assessed with bromodeoxyuridine (BrdU) incorporation, were studied in adult rats with unilateral 6-hydroxydopamine lesions. Both growth factors increased the numbers of newly formed cells in the striatum and substantia nigra to an equal extent following 10 days of treatment. At 3 weeks after termination of growth factor treatment, immunostaining of BrdU-labeled cells with the neuronal marker NeuN revealed a significant increase in newly generated neurons in the striatum. In correspondence, many doublecortin-labeled neuroblasts were also observed in the denervated striatum following growth factor treatment. Further evaluation suggested that a subset of these new neurons expresses the early marker for striatal neurons Pbx. However, no BrdU-positive cells were co-labeled with DARPP-32, a protein expressed by mature striatal projection neurons. Both in the striatum and in the substantia nigra there were no indications of any newly born cells differentiating into dopaminergic neurons following growth factor treatment, such that BrdU-labeled cells never co-expressed tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis. In conclusion, our results suggest that administration of these growth factors is capable of recruiting new neurons into the striatum of hemiparkinsonian rats. 相似文献
13.
目的:观察肌酸对帕金森病模型大鼠黑质多巴胺能神经元的保护作用及其机制。方法:30只雄性SD大鼠随机分成3组:对照组(A组),6-羟多巴胺(6-OHDA)组(B组),肌酸+6-OHDA组(C组),每组各10只。A组不注射6-OHDA,B组进行6-OHDA造模,C组在造模前5天每天给予肌酸(100 mg/kg)灌胃,连续两周,B组给予生理盐水4 ml灌胃。分别观察各组动物行为学、黑质多巴胺能神经元数量及氧化应激指标谷胱甘肽(GSH)和丙二醛(MDA)水平变化。结果:6-OHDA立体定向注射后,实验大鼠出现阿朴吗啡诱导的旋转行为,黑质致密部多巴胺能神经元显著减少,GSH含量降低、MDA水平升高;肌酸能够减轻动物行为学异常(P0.01)、显著增加黑质致密部多巴胺神经元数量(P0.01),拮抗6-OHDA诱导的氧化应激水平升高(P0.01)。结论:肌酸对6-OHDA诱导的多巴胺神经元损伤具有明显保护作用,其机制与抑制氧化应激损伤有关。 相似文献
14.
In an acute study, cholecystokinin octapeptide sulfate (CCK) in doses of 1, 10 or 100 micrograms/kg body weight was injected intraperitoneally into rats just prior to the dark cycle. Rats were sacrificed two hours following the CCK injection. Norepinephrine levels were elevated in the dorsal amygdala of rats injected with 10 micrograms of CCK as well as in the septum of rats injected with 1 and 10 micrograms of CCK. The dopamine level in the septum of rats injected with 1 microgram of CCK as well as the gamma-aminobutyric acid (GABA) level in the lateral hypothalamus of rats injected with 10 micrograms of CCK were also elevated. In a chronic study, CCK (1 microgram/kg body weight/h) was subcutaneously infused into rats with Alzet osmotic minipump for seven consecutive days. The daily food consumption did not change during the 7 days of CCK infusion. The dopamine turnover in the striatum accelerated and the GABA level increased. On the contrary, dopamine metabolism in the substantia nigra and locus coeruleus decreased. Furthermore, the serotonin level in the substantia nigra decreased. Norepinephrine levels decreased in the nucleus paraventricularis, the locus coeruleus and the substantia nigra. The results suggest that peripherally administered CCK may act on the monoaminergic neurons and GABAergic neurons in the brain. 相似文献
15.
本研究的目的是观察雌激素对多巴胺(DA)能神经元是否具有保护作用。去卵巢(OVX)大鼠分别给予生理盐水(NS)和苯甲酸雌二醇(EB)处理,1周后6OHDA造模,造模2周后灌注取材;利用免疫组化法观察黑质内DA阳性神经元的数量、纹状体中DA能末梢的变化;用TUNEL法观察黑质凋亡细胞的数目并对纹状体中胆碱能神经元进行乙酰胆碱酯酶(AChE)染色,观察其退变情况。结果显示和NS组相比,EB组黑质内DA能神经元数量多、凋亡细胞数少(P<0.05);NS组纹状体内DA能神经元末梢减少60%左右,胆碱能神经元退变明显。结果提示雌激素对DA能神经元具有保护作用,在很大程度上可能与抑制神经元凋亡有关。 相似文献
16.
Dopamine release from the rat substantia nigra in vitro. Effect of raphe lesions and veratridine stimulation 总被引:9,自引:0,他引:9
In order to eliminate the 5-hydroxytryptaminergic input to the substantia nigra lesions were placed in the dorsal and medial raphe nuclei in a number of rats. The release of exogenously applied [3H]dopamine from the partially denervated substantia nigra was determined in vitro and found to be very similar to the release observed from slices of control substantia nigra. These results lend further support to the theory that the release of exogenously applied [3H]dopamine at the level of the substantia nigra occurs mainly from dopaminergic dendrites, rather than from terminals of 5-hydroxytryptamine-containing neurons.A veratridine-induced release of [3H]dopamine from the pars reticulata of the substantia nigra is also described. An almost complete blockade of veratridine (3.0 μM) stimulation was observed with 100 nM tetrodotoxin. Similar effects of veratridine and tetrodotoxin were also observed on [3H]dopamine release from slices of corpus striatum. These results suggest that dendrites of the dopaminergic neurones in the substantia nigra contain fast, tetrodotoxin-sensitive sodium channels. 相似文献
17.
We have developed dissociated primary neuronal cultures obtained from the substantia nigra and from the ventral tegmental area of postnatal rats (two to three days old). After making brain slices, the regions of the substantia nigra and the ventral tegmental area were separately dissected. The removed fragments of brain tissue were dissociated and cultured on a glial feeder layer. Double immunocytochemical labeling for tyrosine hydroxylase and GABA on cultures grown for two to three weeks showed the presence of 42% dopaminergic and 39% GABAergic neurons in substantia nigra cultures, whereas in ventral tegmental area cultures there were 65% dopaminergic and 21% GABAergic neurons. The dopaminergic neurons were characterized by thick and straight primary processes dividing into several branches. Varicosities were found mainly on distal parts of the processes. In contrast, GABAergic neurons possessed highly branched thick and thin primary processes with intensive arborization and numerous varicosities. Co-existence of dopamine and cholecystokinin was found in about 70% of dopaminergic neurons from the substantia nigra and in about 35% of dopaminergic neurons from the ventral tegmental area. Physiological properties of these cultured dopaminergic neurons were investigated with the whole-cell version of the patch-clamp method. After each physiological experiment, immunocytochemical labeling confirmed that the cell was dopaminergic. Properties of single action potentials, with an action potential height of 92 mV and duration of 1.6 ms, were similar to those reported for dopaminergic neurons in brain slices. The neurons showed a high resting potential, and no spontaneous firing of action potentials. Constant current depolarizations elicited trains of action potentials. In the majority of cells, the train stopped firing within a few seconds, while in some cells it lasted indefinitely. When the cell was hyperpolarized, the voltage response started to decline slowly (sag), indicating the presence of hyperpolarization-activated currents (time-dependent inward rectification). These results show that by using our culture method it is possible to obtain separate dissociated cultures of the substantia nigra and the ventral tegmental area from newborn rats. Because they are rich in functional dopaminergic neurons, these cultures will be a useful tool for studying various properties of dopaminergic neurons. 相似文献
18.
This study was intended to investigate the possibility of a relationship between compensation of sensory-motor asymmetries induced by unilateral substantia nigra lesions and changes in inter-hemispheric nigrostriatal projections. Adult male rats were used in two experiments:Experiment I. Animals received an injection of either 6-OH-dopamine or kainic acid into the substantia nigra. They were observed for intervals of 7, 21 or 90 days with respect to spontaneous turning, d-amphetamine-induced turning and other sensory-motor asymmetries. Interhemispheric nigrostriatal projections were examined by injecting horseradish peroxidase into the striatum homolateral to the nigral lesion. Labeled perikarya were counted in the contralateral substantia nigra. A significant increase in number of labeled neurons was observed 7 and 21 days, but not 90 days after the nigral lesion in comparison to control animals. Spontaneous lesion-induced turning behavior ceased within the first postoperative week. After 21 and 90 days it was still possible to elicit turning by injection of amphetamine.Experiment II. An increase in number of interhemispheric nigro striatal projections one week after the nigral lesion was also found when Nuclear Yellow was used as a tracer substance. Animals received a unilateral injection of Fast Blue into the caudate nucleus, followed by an injection of Nuclear Yellow at the identical locus one week later. An increase in number of Nuclear Yellow-labeled neurons was registered only if the injection of Fast Blue was followed by a 6-hydroxydopamine lesion in the homolateral substantia nigra within 24 h. Interhemispheric nigro striatal projections were of monoaminergic as well as of non-monoaminergic origin, as revealed by histofluorescent tracing for monoaminergic neurons.These results may reflect sprouting of interhemispheric fiber projections in response to, or as correlates of, behavioral compensation of the lesion-induced behavioral asymmetries. 相似文献
19.
Pereyra-Muñoz N Rugerio-Vargas C Angoa-Pérez M Borgonio-Pérez G Rivas-Arancibia S 《Journal of chemical neuroanatomy》2006,31(2):114-123
The purpose of this work was to study if chronic low-dose ozone exposure could per se induce oxidative damage to neurons of striatum and substantia nigra. Thirty male Wistar rats were divided into three groups--Group 1: exposed to an air stream free of ozone; Group 2: exposed for 15 days to ozone; Group 3: exposed for 30 days to ozone. Ozone exposure was carried out daily for 4 h at a 0.25 ppm dose. Each group was then tested for (1) motor activity, (2) quantification of lipid peroxidation levels, (3) Klüver-Barrera staining, and (4) immunohistochemistry for tyrosine hydroxylase (TH), dopamine and adenosine 3',5'-monophosphate-regulated phosphoprotein of 32 kD (DARPP-32), inducible nitric oxide synthase (iNOS), and superoxide dismutase (SOD), to study neuronal alterations in striatum and substantia nigra. Results indicate that ozone exposure causes a significant decrease in motor activity. Ozone produced lipid peroxidation, morphological alterations, loss of fibers and cell death of the dopaminergic neurons. The DARPP-32, iNOS and SOD expression increased with repetitive ozone exposure. These alterations suggest that ozone causes oxidative stress which induces oxidative damage to substantia nigra and striatum of the rat. 相似文献
20.
腺病毒载体介导的lacZ基因在NG细胞系及大鼠黑质的表达 总被引:1,自引:0,他引:1
本实验用标记基因lacZ5型重组腺病毒(Ad5CMVlacZ)转染培养的NG细胞系,X-gal染色检测转染效率.在培养的NG细胞系,当病毒滴度为2×108时,转集率达到50%,当滴度为2×109时,转染率达100%,有较好的量效关系;固定病毒液度为1010,培养2~16h,细胞的转染率随时间延长而提高,有较好的时效关系。将Ad5CMVlacZ注射到大鼠黑质部位后,分别于注射后3~120d取脑、切片、X-gal染色,发现黑质局部从第7d开始有部分蓝染,第10d达高峰,注射局部感染率100%;90d时开始下降,持续至120d;纹状体等其它部位无蓝染.上述结果提示,腺病毒载体介导的标记基因可在培养的神经细胞系和中脑黑质部位高效表达,为进一步开展中枢神经系统退变性疾病尤其是帕金森氏病的基因治疗奠定基础。 相似文献