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1.
Lymph nodes (LNs) are secondary lymphoid organs, which are strategically located throughout the body to allow for trapping and presentation of foreign antigens from peripheral tissues to prime the adaptive immune response. Juxtaposed between innate and adaptive immune responses, the LN is an ideal site to study immune cell interactions1,2. Lymphocytes (T cells, B cells and NK cells), dendritic cells (DCs), and macrophages comprise the bulk of bone marrow-derived cellular elements of the LN. These cells are strategically positioned in the LN to allow efficient surveillance of self antigens and potential foreign antigens3-5. The process by which lymphocytes successfully encounter cognate antigens is a subject of intense investigation in recent years, and involves an integration of molecular contacts including antigen receptors, adhesion molecules, chemokines, and stromal structures such as the fibro-reticular network2,6-12. Prior to the development of high-resolution real-time fluorescent in vivo imaging, investigators relied on static imaging, which only offers answers regarding morphology, position, and architecture. While these questions are fundamental in our understanding of immune cell behavior, the limitations intrinsic with this technique does not permit analysis to decipher lymphocyte trafficking and environmental clues that affect dynamic cell behavior. Recently, the development of intravital two-photon laser scanning microscopy (2P-LSM) has allowed investigators to view the dynamic movements and interactions of individual cells within live LNs in situ12-16. In particular, we and others have applied this technique to image cellular behavior and interactions within the popliteal LN, where its compact, dense nature offers the advantage of multiplex data acquisition over a large tissue area with diverse tissue sub-structures11,17-18. It is important to note that this technique offers added benefits over explanted tissue imaging techniques, which require disruption of blood, lymph flow, and ultimately the cellular dynamics of the system. Additionally, explanted tissues have a very limited window of time in which the tissue remains viable for imaging after explant. With proper hydration and monitoring of the animal''s environmental conditions, the imaging time can be significantly extended with this intravital technique. Here, we present a detailed method of preparing mouse popliteal LN for the purpose of performing intravital imaging.  相似文献   

2.
Monitoring cellular communication by intravital deep-tissue multi-photon microscopy is the key for understanding the fate of immune cells within thick tissue samples and organs in health and disease. By controlling the scanning pattern in multi-photon microscopy and applying appropriate numerical algorithms, we developed a striped-illumination approach, which enabled us to achieve 3-fold better axial resolution and improved signal-to-noise ratio, i.e. contrast, in more than 100 µm tissue depth within highly scattering tissue of lymphoid organs as compared to standard multi-photon microscopy. The acquisition speed as well as photobleaching and photodamage effects were similar to standard photo-multiplier-based technique, whereas the imaging depth was slightly lower due to the use of field detectors. By using the striped-illumination approach, we are able to observe the dynamics of immune complex deposits on secondary follicular dendritic cells – on the level of a few protein molecules in germinal centers.  相似文献   

3.
Intravital microscopy is a method that can be used to investigate different processes in different regions and vessels in living animals. In this protocol, we describe intravital microscopy of mesentery veins. This can be performed in a short period of time with reproducible results showing leukocyte-endothelial interactions in vivo. We describe an inflammatory setting after LPS challenge of the endothelium. But in this model one can apply many different types of inflammatory conditions, like bacterial, chemical or biological and investigate the administration of drugs and their direct effects on the living animal and its impact on leukocyte recruitment. This protocol has been applied successfully to a number of different treatments of mice and their effects on inflammatory response in vessels. Herein, we describe the visualization of leukocytes and platelets by fluorescently labeling these with rhodamine 6G. Additionally, any specific imaging can be performed using targeted fluorescently labeled molecules.  相似文献   

4.
Secondary lymphoid organs including lymph nodes are composed of stromal cells that provide a structural environment for homeostasis, activation and differentiation of lymphocytes. Various stromal cell subsets have been identified by the expression of the adhesion molecule CD31 and glycoprotein podoplanin (gp38), T zone reticular cells or fibroblastic reticular cells, lymphatic endothelial cells, blood endothelial cells and FRC-like pericytes within the double negative cell population. For all populations different functions are described including, separation and lining of different compartments, attraction of and interaction with different cell types, filtration of the draining fluidics and contraction of the lymphatic vessels. In the last years, different groups have described an additional role of stromal cells in orchestrating and regulating cytotoxic T cell responses potentially dangerous for the host. Lymph nodes are complex structures with many different cell types and therefore require a appropriate procedure for isolation of the desired cell populations. Currently, protocols for the isolation of lymph node stromal cells rely on enzymatic digestion with varying incubation times; however, stromal cells and their surface molecules are sensitive to these enzymes, which results in loss of surface marker expression and cell death. Here a short enzymatic digestion protocol combined with automated mechanical disruption to obtain viable single cells suspension of lymph node stromal cells maintaining their surface molecule expression is proposed.  相似文献   

5.
The stroma is a key component of the lymph node structure and function. However, little is known about its origin, exact cellular composition and the mechanisms governing its formation. Lymph nodes are always encapsulated in adipose tissue and we recently demonstrated the importance of this relation for the formation of lymph node stroma. Adipocyte precursor cells migrate into the lymph node during its development and upon engagement of the Lymphotoxin-b receptor switch off adipogenesis and differentiate into lymphoid stromal cells (Bénézech et al.14). Based on the lymphoid stroma potential of adipose tissue, we present a method using a lymph node/fat pad chimera that allows the lineage tracing of lymph node stromal cell precursors. We show how to isolate newborn lymph nodes and EYFP+ embryonic adipose tissue and make a LN/ EYFP+ fat pad chimera. After transfer under the kidney capsule of a host mouse, the lymph node incorporates local adipose tissue precursor cells and finishes its formation. Progeny analysis of EYFP+ fat pad cells in the resulting lymph nodes can be performed by flow-cytometric analysis of enzymatically digested lymph nodes or by immunofluorescence analysis of lymph nodes cryosections. By using fat pads from different knockout mouse models, this method will provide an efficient way of analyzing the origin of the different lymph node stromal cell populations.  相似文献   

6.
The advent of intravital microscopy in experimental rodent malaria models has allowed major advances to the knowledge of parasite-host interactions 1,2. Thus, in vivo imaging of malaria parasites during pre-erythrocytic stages have revealed the active entrance of parasites into skin lymph nodes 3, the complete development of the parasite in the skin 4, and the formation of a hepatocyte-derived merosome to assure migration and release of merozoites into the blood stream 5. Moreover, the development of individual parasites in erythrocytes has been recently documented using 4D imaging and challenged our current view on protein export in malaria 6. Thus, intravital imaging has radically changed our view on key events in Plasmodium development. Unfortunately, studies of the dynamic passage of malaria parasites through the spleen, a major lymphoid organ exquisitely adapted to clear infected red blood cells are lacking due to technical constraints.Using the murine model of malaria Plasmodium yoelii in Balb/c mice, we have implemented intravital imaging of the spleen and reported a differential remodeling of it and adherence of parasitized red blood cells (pRBCs) to barrier cells of fibroblastic origin in the red pulp during infection with the non-lethal parasite line P.yoelii 17X as opposed to infections with the P.yoelii 17XL lethal parasite line 7. To reach these conclusions, a specific methodology using ImageJ free software was developed to enable characterization of the fast three-dimensional movement of single-pRBCs. Results obtained with this protocol allow determining velocity, directionality and residence time of parasites in the spleen, all parameters addressing adherence in vivo. In addition, we report the methodology for blood flow quantification using intravital microscopy and the use of different colouring agents to gain insight into the complex microcirculatory structure of the spleen. Ethics statement All the animal studies were performed at the animal facilities of University of Barcelona in accordance with guidelines and protocols approved by the Ethics Committee for Animal Experimentation of the University of Barcelona CEEA-UB (Protocol No DMAH: 5429). Female Balb/c mice of 6-8 weeks of age were obtained from Charles River Laboratories.  相似文献   

7.
Besides being a physical scaffold to maintain tissue morphology, the extracellular matrix (ECM) is actively involved in regulating cell and tissue function during development and organ homeostasis. It does so by acting via biochemical, biomechanical, and biophysical signaling pathways, such as through the release of bioactive ECM protein fragments, regulating tissue tension, and providing pathways for cell migration. The extracellular matrix of the tumor microenvironment undergoes substantial remodeling, characterized by the degradation, deposition and organization of fibrillar and non-fibrillar matrix proteins. Stromal stiffening of the tumor microenvironment can promote tumor growth and invasion, and cause remodeling of blood and lymphatic vessels. Live imaging of matrix proteins, however, to this point is limited to fibrillar collagens that can be detected by second harmonic generation using multi-photon microscopy, leaving the majority of matrix components largely invisible. Here we describe procedures for tumor inoculation in the thin dorsal ear skin, immunolabeling of extracellular matrix proteins and intravital imaging of the exposed tissue in live mice using epifluorescence and two-photon microscopy. Our intravital imaging method allows for the direct detection of both fibrillar and non-fibrillar matrix proteins in the context of a growing dermal tumor. We show examples of vessel remodeling caused by local matrix contraction. We also found that fibrillar matrix of the tumor detected with the second harmonic generation is spatially distinct from newly deposited matrix components such as tenascin C. We also showed long-term (12 hours) imaging of T-cell interaction with tumor cells and tumor cells migration along the collagen IV of basement membrane. Taken together, this method uniquely allows for the simultaneous detection of tumor cells, their physical microenvironment and the endogenous tissue immune response over time, which may provide important insights into the mechanisms underlying tumor progression and ultimate success or resistance to therapy.  相似文献   

8.
In the field of immunology, to understand the progression of an immune response against a vaccine, an infection or a tumour, the response is often followed over time. Similarly, the study of lymphocyte homeostasis requires time course experiments. Performing these studies within the same mouse is ideal to reduce the experimental variability as well as the number of mice used. Blood withdrawal allows performance of time course experiments, but it only gives information about circulating lymphocytes and provides a limited number of cells. Since lymphocytes circulating through the body and residing in the lymph nodes have different properties, it is important to examine both locations. The sequential removal of lymph nodes by surgery provides a unique opportunity to follow an immune response or immune cell expansion in the same mouse over time. Furthermore, this technique yields between 1-2x10(6) cells per lymph node which is sufficient to perform phenotypic characterization and/or functional assays. Sequential lymph node surgery or lymphadenectomy has been successfully used by us and others. Here, we describe how the brachial and inguinal lymph nodes can be removed by making a small incision in the skin of an anesthetised mouse. Since the surgery is superficial and done rapidly, the mouse recovers very quickly, heals well and does not experience excessive pain. Every second day, it is possible to harvest one or two lymph nodes allowing for time course experiments. This technique is thus suitable to study the characteristics of lymph node-residing lymphocytes over time. This approach is suitable to various experimental designs and we believe that many laboratories would benefit from performing sequential lymph node surgeries.  相似文献   

9.
The prognosis in virtually all solid tumors depends on the presence or absence of lymph node metastases.1-3 Surgical treatment most often combines radical excision of the tumor with a full lymphadenectomy in the drainage area of the tumor. However, removal of lymph nodes is associated with increased morbidity due to infection, wound breakdown and lymphedema.4,5 As an alternative, the sentinel lymph node procedure (SLN) was developed several decades ago to detect the first draining lymph node from the tumor.6 In case of lymphogenic dissemination, the SLN is the first lymph node that is affected (Figure 1). Hence, if the SLN does not contain metastases, downstream lymph nodes will also be free from tumor metastases and need not to be removed. The SLN procedure is part of the treatment for many tumor types, like breast cancer and melanoma, but also for cancer of the vulva and cervix.7 The current standard methodology for SLN-detection is by peritumoral injection of radiocolloid one day prior to surgery, and a colored dye intraoperatively. Disadvantages of the procedure in cervical and vulvar cancer are multiple injections in the genital area, leading to increased psychological distress for the patient, and the use of radioactive colloid.Multispectral fluorescence imaging is an emerging imaging modality that can be applied intraoperatively without the need for injection of radiocolloid. For intraoperative fluorescence imaging, two components are needed: a fluorescent agent and a quantitative optical system for intraoperative imaging. As a fluorophore we have used indocyanine green (ICG). ICG has been used for many decades to assess cardiac function, cerebral perfusion and liver perfusion.8 It is an inert drug with a safe pharmaco-biological profile. When excited at around 750 nm, it emits light in the near-infrared spectrum around 800 nm. A custom-made multispectral fluorescence imaging camera system was used.9.The aim of this video article is to demonstrate the detection of the SLN using intraoperative fluorescence imaging in patients with cervical and vulvar cancer. Fluorescence imaging is used in conjunction with the standard procedure, consisting of radiocolloid and a blue dye. In the future, intraoperative fluorescence imaging might replace the current method and is also easily transferable to other indications like breast cancer and melanoma.  相似文献   

10.
目的:探讨胃癌术中前哨淋巴结(sentinel lymph node,SLN)定位检测的可行性及其临床意义。方法:使用亚甲蓝对40例胃癌患者行前哨淋巴结术中标识活检,随后行D2或D2以上手术。结果:40例胃癌患者中,38例找到前哨淋巴结,检出率为38/40(95%),有32例存在SLN转移,8例SLN为唯一转移部位,且均为T1、T2期。由SLN的病理学状态来预测胃周围淋巴结转移情况的敏感性为32/34(94.12%),特异性为4/4(100%),假阴性率为2/34(5.88%),准确率为34/38(89.47%),其中假阴性的2例,肿瘤都处于T4期。结论:胃癌SLN定位及活检技术能较准确反映早期胃癌的淋巴结转移状况,但对进展期胃癌而言假阴性率较高,对胃癌整个区域淋巴结状态预测的可靠性和可行性尚需进一步验证。  相似文献   

11.
目的:探讨胃癌术中前哨淋巴结(sentinel lymph node,SLN)定位检测的可行性及其临床意义。方法:44t用亚甲蓝对40例胃癌患者行前哨淋巴结术中标识活检,随后行D2或D2以上手术。结果:40例胃癌患者中,38例找到前哨淋巴结,检出率为38/40(95%),有32例存在SLN转移,8例SLN为唯一转移部位,且均为T1、T2期。由SLN的病理学状态来预测胃周围淋巴结转移情况的敏感性为32/34(94.12%),特异性为4/4(100%),假阴性率为2/34(5.88%),准确率为34/38(89.47%),其中假阴性的2例,肿瘤都处于T4期。结论:胃癌SLN定位及活检技术能较准确反映早期胃癌的淋巴结转移状况,但对进展期胃癌而言假阴性率较高,对胃癌整个区域淋巴结状态预测的可靠性和可行性尚需进一步验证。  相似文献   

12.
Two-photon Microscopy (TPM) provides image acquisition in deep areas inside tissues and organs. In combination with the development of new stereotactic tools and surgical procedures, TPM becomes a powerful technique to identify "niches" inside organs and to document cellular "behaviors" in live animals. While intravital imaging provides information that best resembles the real cellular behavior inside the organ, it is both more laborious and technically demanding in terms of required equipment/procedures than alternative ex vivo imaging acquisition. Thus, we describe a surgical procedure and novel "stereotactic" organ holder that allows us to follow the movements of Foxp3+ cells within the thymus. Foxp3 is the master regulator for the generation of regulatory T cells (Tregs). Moreover, these cells can be classified according to their origin: ie. thymus-differentiated Tregs are called "naturally-occurring Tregs" (nTregs), as opposed to peripherally-converted Tregs (pTregs). Although significant amount of research has been reported in the literature concerning the phenotype and physiology of these T cells, very little is known about their in vivo interactions with other cells. This deficiency may be due to the absence of techniques that would permit such observations. The protocol described in this paper provides a remedy for this situation. Our protocol consists of using nude mice that lack an endogenous thymus since they have a punctual mutation in the DNA sequence that compromises the differentiation of some epithelial cells, including thymic epithelial cells. Nude mice were gamma-irradiated and reconstituted with bone marrows (BM) from Foxp3-KI(gfp/gfp) mice. After BM recovery (6 weeks), each animal received embryonic thymus transplantation inside the kidney capsule. After thymus acceptance (6 weeks), the animals were anesthetized; the kidney containing the transplanted thymus was exposed, fixed in our organ holder, and kept under physiological conditions for in vivo imaging by TPM. We have been using this approach to study the influence of drugs in the generation of regulatory T cells.  相似文献   

13.
目的:通过对比两种不同的临床治疗乳腺癌的效果,提出临床治疗乳腺癌更可靠的方案,为临床治疗和相关研究提供参考。方法:选取我院2010年12月至2014年12月期间我院临床收治的乳腺癌患者56例,根据患者临床治疗手术方法情况,分成了研究组和对照组,研究组患者给予乳腔镜腋窝淋巴结清扫术,对照组患者均给予常规的腋窝淋巴结清扫术,观察和比较两者患者实施不同手术治疗后的手术时间、住院费用、术中出血量和并发症发生情况。结果:研究组患者的手术时间长于对照组,研究组患者的住院费用高于对照组,而患者术中出血量研究组患者也低于对照组患者,组问比较差异均具有统计学意义(P0.05);两组患者术后并发症的发生率比较,差异无统计学意义(P0.05)。结论:与常规腋窝淋巴结清扫术相比较,乳腔镜手术所需时间较长,并且治疗费用偏高,临床上应给予患者的个体差异情况有针对性的选择实施。  相似文献   

14.
目的:探讨病理分期在颌颈部淋巴结核治疗中的价值,以期寻找颌颈部淋巴结核的最佳治疗方案。方法:收集我科近5年的临床资料,对颌颈部淋巴结核患者的发病及治疗情况作一临床统计,并结合淋巴结核的病理分期对之加以分析,寻找治疗规律。结果:所有颌颈部淋巴结核患者按病理分期采取不同治疗方案,均达到较佳治疗效果,处于病理初期和中期的患者,临床治疗周期明显小于常规化疗。结论:遵从病理分期治疗颌颈部淋巴结核是一种较为科学合理的治疗思路和方法。  相似文献   

15.
Alterations in retinal blood flow can contribute to, or be a consequence of, ocular disease and visual dysfunction. Therefore, quantitation of altered perfusion can aid research into the mechanisms of retinal pathologies. Intravital video microscopy of fluorescent tracers can be used to measure vascular diameters and bloodstream velocities of the retinal vasculature, specifically the arterioles branching from the central retinal artery and of the venules leading into the central retinal vein. Blood flow rates can be calculated from the diameters and velocities, with the summation of arteriolar flow, and separately venular flow, providing values of total retinal blood flow. This paper and associated video describe the methods for applying this technique to mice, which includes 1) the preparation of the eye for intravital microscopy of the anesthetized animal, 2) the intravenous infusion of fluorescent microspheres to measure bloodstream velocity, 3) the intravenous infusion of a high molecular weight fluorescent dextran, to aid the microscopic visualization of the retinal microvasculature, 4) the use of a digital microscope camera to obtain videos of the perfused retina, and 5) the use of image processing software to analyze the video. The same techniques can be used for measuring retinal blood flow rates in rats.  相似文献   

16.
目的:研究超声成像技术对腋窝淋巴结性质的诊断价值。方法:从2013年5月至2014年2月,选择我院50例乳腺癌患者,对所有患者进行弹性成像技术检测出74个腋窝淋巴结。对所有腋窝淋巴结使用四分法进行评分,将其与手术病理结果进行比较。结果:74个腋窝淋巴结中,反应性淋巴结有42个,纵径为(0.9-2.4)cm,平均纵径为(1.31±0.33)cm;乳腺癌腋窝淋巴结转移个数为25个,纵径为(1.2±3.8)cm,平均纵径为(2.04±0.72)cm。良性淋巴结弹性评分大多为1分(54.55%)以及2分(27.27%),恶性淋巴结评分多为3分(63.33%)以及4分(20.00%)。恶性淋巴结评分为(3.12±0.61)分,良性淋巴结评分为(1.68±0.74)分,结果显示,两组淋巴结弹性评分具有较大差异(即P<0.05),具有可比性。结论:综上所述,超声弹性成像技术操作较为简便,效果较为直观,评分法能够提供组织的硬度信息,在临床工作中,与常规超声联合应用有利于提高评价腋窝淋巴结良恶性性质的准确度。值得临床推荐使用。  相似文献   

17.
《Cell reports》2020,30(3):893-904.e6
  1. Download : Download high-res image (467KB)
  2. Download : Download full-size image
  相似文献   

18.
摘要 目的:分析上海市第一人民医院2015年至2019年期间250例分期为IB~IIA期的宫颈癌患者腹主动脉旁淋巴结(para-aortic lymph node,PALN)转移的危险因素,并探讨在早期宫颈癌手术中PALN清扫的意义。方法:回顾性分析250例宫颈癌患者的临床及病理资料,这些患者均接受了腹腔镜或开腹根治性子宫切除术+双侧盆腔淋巴结(pelvic lymph node,PLN)及PALN清扫术,采用统计学方法,通过单因素分析及多因素分析来讨论影响PALN转移的危险因素。结果:在250例宫颈癌患者中,PLN的转移率为27.60 %(69/250),PALN的转移率为6.40 %(16/250),在PLN转移阳性中,有15例PALN转移阳性的患者,转移率为21.74 %(15/69)。单因素分析显示,肿瘤最大直径、分期、淋巴脉管间隙浸润(lymph vascular space invasion,LVSI)、PLN转移以及鳞状上皮细胞癌抗原(SCC-Ag)与PALN转移有关(P<0.05),而多因素分析显示,分期为IIA期、PLN转移阳性以及PLN转移的个数≥3个是PALN转移的独立危险因素。将这些危险因素代入回归方程以建立临床预测模型,Y=-5.691+1.497×IIA期+3.627×PLN转移(Y代表PALN转移率),利用受试者工作特征(receiver operating characteristic,ROC)曲线评估这些独立危险因素对于判断PALN转移是否具备一定的诊断价值,此时截断值(cut-off value)为0.064,灵敏度为93.80 %,特异度为76.90 %,曲线下面积(AUC)为0.907(P<0.001,95 % CI:0.859~0.955),H-L检验(Hosmer-Lemeshow)发现该模型拟合优度效果较好(P>0.05)。同时通过绘制ROC曲线发现,当PLN转移个数≥3个以及肿瘤最大直径≥3.4 cm时,对判断是否存在PALN转移也具有一定的临床价值。结论:通过分析表明IIA期、PLN转移阳性以及转移个数≥3个是PALN转移的独立危险因素,可以对这些因素展开进行充分的评估与诊断,从而更加优化宫颈癌患者的分期、手术方式、治疗方案,为患者提供个体化临床诊疗,以期提高宫颈癌患者的生存质量,减少术后的并发症,改善患者的预后等。  相似文献   

19.
In the era of intravascular cell application protocols in the context of regenerative cell therapy, the underlying mechanisms of stem cell migration to nonmarrow tissue have not been completely clarified. We describe here the technique of intravital microscopy applied to the mouse cremaster microcirculation for analysis of peripheral bone marrow stem cell migration in vivo. Intravital microscopy of the M. cremaster has been previously introduced in the field of inflammatory research for direct observation of leucocyte interaction with the vascular endothelium. Since sufficient peripheral stem and progenitor cell migration includes similar initial steps of rolling along and firm adhesion at the endothelial lining it is conceivable to apply the M. cremaster model for the observation and quantification of the interaction of intravasculary administered stem cells with the endothelium. As various chemical components can be selectively applied to the target tissue by simple superfusion techniques, it is possible to establish essential microenvironmental preconditions, for initial stem cell recruitment to take place in a living organism outside the bone marrow.  相似文献   

20.
目的:分析系统性淋巴结清扫术对子宫内膜癌患者预后的影响及安全性。方法:选择2010年6月~2012年6月我院收治的68例子宫内膜癌患者作为研究对象,将其随机分为研究组与对照组。对照组行两侧附件+全子宫切除+盆腔淋巴结清扫术,研究组行两侧附件+全子宫切除+系统性腹腔、盆腔主动脉旁淋巴结清扫术。观察和比较两组患者术后3年内的生存率、疾病复发转移率以及并发症的发生率。结果:研究组检出阳性淋巴结15枚,发现4例患者淋巴结转移;对照组患检出阳性淋巴结3枚,发现1例患者淋巴结转移。两组阳性淋巴结检出率及淋巴结转移发现率比较差异无统计学意义(P0.05)。研究组3年内生存率为88.24%,显著高于对照组的67.65%(P0.05);复发转移率为14.71%,显著高于对照组的35.29%(P0.05)。研究组患者术后发生不全性肠梗阻发生率为17.65%,显著高于对照组(P0.05);但两组术后下肢水肿、深静脉血栓、淋巴囊肿、输尿管尿瘘、体温转复时间5 d的发生率对比差异均无统计学意义(P0.05)。结论:系统性淋巴结清扫术可以延长子宫内膜癌患者的3年生存率,降低病灶的复发及转移率,虽然术后不全性肠梗阻的发生率有所增加,但仍在可控范围内。  相似文献   

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