941 resultados para Lymphatic vessels


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以血管生成为靶点的抗肿瘤策略是抗肿瘤领域的研究热点,目前已经发现许多天然和化学合成的抗血管生成药物。鲨鱼软骨作为抗新生血管生成因子的重要来源的研究已有20多年的历史,很多研究显示鲨鱼软骨提取物有抗血管生成活性。但鲨鱼软骨活性多肽的完整分子结构一直未见报道;鲨鱼软骨活性多肽干扰血管生成通路的信号途径尚不明确。 本文应用盐酸胍抽提、丙酮分级沉淀、超滤、凝胶层析等分离技术,从青鲨(Prionace glauca)软骨中分离纯化并鉴定了一种新的具有抗新生血管生成活性的多肽。经SDS-PAGE和N-末端氨基酸序列分析显示,该多肽分子量为15500 Da,采用蛋白数据库分析表明该多肽是一种新发现的鲨鱼软骨多肽(Polypeptide from Prionace glauca,PG155)。 体外实验显示,PG155抑制内皮细胞生长因子(vascular endothelial growth factor,VEGF)介导的人脐静脉内皮细胞(human umbilical vein endothelial cell ,HUVEC)迁移和管腔形成,并呈剂量依赖关系。200 μg/ml PG155对牛主动脉内皮细胞(Bovine Aortic Endothelial Cells,BAECs)和HUVECs及以下癌细胞,包括人肝癌细胞(human hepatoma Bel-7402 cells,Bel-7402)、 口腔上皮癌细胞(human oral epidermoid carcinoma KB cells ,KB)、人结肠癌细胞(human colon cancer HCT-18 cells,HCT-18)和人乳腺癌细胞(human breast MCF7 cancer cells ,MCF7)的增殖均无抑制作用,说明PG155无细胞毒作用。20 μg/ml PG155显著抑制HUVEC的迁移和管腔形成;40-80 μg/ml PG155 对VEGF 介导的HUVEC的迁移和管腔形成几乎完全抑制。 体内实验显示,PG155显著抑制斑马鱼胚胎模型新生血管生成,并呈剂量依赖关系。形态学观察表明PG155显著抑制斑马鱼胚胎肠下静脉(subintestinal vessels, SIVs)的生长,随着浓度的升高SIVs的生长可受到完全抑制。碱性磷酸酶染色分析显示,在一定浓度范围内,PG155随着浓度的升高对斑马鱼胚胎整体血管生成抑制作用依次增强。160 μg/ml PG155会引起斑马鱼胚胎心脏功能障碍。 由海洋生物中发现新的肿瘤新生血管生成抑制剂国内外的报道较少,我们的工作表明鲨鱼软骨可作为血管生成抑制剂的重要来源,鲨鱼软骨活性多肽PG155由于具有极低的细胞毒作用,并能抑制VEGF介导的血管生成过程,有希望成为一类新型抗肿瘤药物。

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血管生成是肿瘤生长、发展的必经之路,并且与实体瘤的发生、转移有着密切的关系,抑制肿瘤新生血管生成具有特异性高、疗效好、不易产生耐药性以及毒副作用低等特点,因此抑制肿瘤血管形成可望成为治疗癌症的一个突破点,以抗血管生成为主的肿瘤生物治疗研究已成为近十年的研究热点。玻璃海鞘(Coina intestinalis)属于内性目、玻璃海鞘科,因其进化上的独特地位常作为研究神经发育、免疫系统进化的材料。在其它种属的海鞘中分离发现了多种具有抗肿瘤活性的多肽,但关于玻璃海鞘抗血管生成活性多肽的分离纯化和活性研究未见报道。本文利用多种分离纯化手段,采用活性追踪的方法首次从玻璃海鞘中分离得到具有抗新生血管生成作用的多肽,并对其抗血管生成活性做了初步研究。 本研究利用冷丙酮分级沉淀,超滤截留分子量小于5kDa的蛋白,再经SephadexG25、Superdex75柱层析,µRPC C2/C18反相柱层析等分离手段,采用活性追踪的方法,由玻璃海鞘(Coina intestinalis)中分离纯化出抗血管生成多肽PCI,据保留时间计算其分子量为1.8 kDa。MTT检测表明其对人脐静脉血管内皮细胞(HUVEC)具有强烈的抑制作用,IC50为7.5 μg/ml,并对多种肿瘤细胞有直接的抑制作用。斑马鱼胚胎体内实验进一步表明PCI在40 μg/ml的浓度下作用12h,斑马鱼胚胎新生血管生成受到显著抑制,肠下静脉血管长度为正常组的30%,斑马鱼胚胎血管生成率为正常组的45%。

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本文介绍了我们承担研制的国家“863”计划1000m及6000m无缆水下机器人的回收系统.回收系统在4级海况下不用专用母船能够成功地回收水下机器人,依据母船、海况、水下机器人及其他具体情况,介绍了两种不同的回收方案和回收器,经海上试验证明是有效和可行的。

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To explore the presence of depression, anxiety and cardiac events after coronary artery bypass grafting (CABG) prospectively and comparably. To analysis influential factors of depression and anxiety ( peri-operation and 1 year after operation ), and the effection on cardiac events in the year after operation. We followed the patients who underwent scheduled consecutive CABG. We interviewed patients to assess depression, anxiety symptoms using self-rating depression scale( SDS) and self-rating anxiety scale(SAS)before operation , before discharge and 1 year after operation. And cardiac events were also identified. All patients were divided into the group with depression and/or anxiety symptoms or the other group without depression and/or anxiety symptoms 3 times according to depression and anxiety symptoms before operation , before discharge and 1 year after operation. 69 patients completed the follow-up.24 patients (34.8%) had depression and/or anxiety symptoms before CABG, 31 patients (44.9%) had depression and/or anxiety symptoms before discharge, and 10 patients (14.5%) had depression and/or anxiety symptoms 1 year after operation. 6 patients(8.7%) had cardiac events, and 5 patients were re-admitted. Arhythmia before and after operation, the quantity of blood vessel grafted, length of stay , depression and anxiety symptoms before operation, cardiac events may lead to depression and anxiety symptoms 1 year after operation. The use of cardiopulmonary bypass grafting (CPB), Arhythmia after operation, the prolonged length of stay are influential factors of cardiac events. Though the incidence of depression and/or anxiety symptoms 1 year after operation is lower than before operation and before discharge, it is high still. Arhythmia before and after operation, the more blood vessels grafted, the prolonged length of stay , depression and anxiety symptoms before operation and cardiac events could be risk factors of depression and anxiety symptoms 1 year after operation. Much attention must be paid to this phenomenon. Heavy patient's condition, complicated surgery are risk factors of cardiac events, and bad emotion before operation and before discharge are independent to cardiac events. Key words: perspective research; depression;anxiety; coronary artery bypass grafting; follow up

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Skin flap procedures are commonly used in plastic surgery. Failures can follow, leading to the necrosis of the flap. Therefore, many studies use LLLT to improve flap viability. Currently, the LED has been introduced as an alternative to LLLT. the objective of this study was to evaluate the effect of LLLT and LED on the viability of random skin flaps in rats. Forty-eight rats were divided into four groups, and a random skin flap (10 x 4 cm) was performed in all animals. Group 1 was the sham group; group 2 was submitted to LLLT 660 nm, 0.14 J; group 3 with LED 630 nm, 2.49 J, and group 4 with LLLT 660 nm, with 2.49 J. Irradiation was applied after surgery and repeated on the four subsequent days. On the 7th postoperative day, the percentage of flap necrosis was calculated and skin samples were collected from the viable area and from the transition line of the flap to evaluate blood vessels and mast cells. the percentage of necrosis was significantly lower in groups 3 and 4 compared to groups 1 and 2. Concerning blood vessels and mast cell numbers, only the animals in group 3 showed significant increase compared to group 1 in the skin sample of the transition line. LED and LLLT with the same total energies were effective in increasing viability of random skin flaps. LED was more effective in increasing the number of mast cells and blood vessels in the transition line of random skin flaps.

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The presence of tissue specific precursor cells is an emerging concept in organ formation and tissue homeostasis. Several progenitors are described in the kidneys. However, their identity as a true stem cell remains elusive. Here, we identify a neonatal kidney-derived c-kit(+) cell population that fulfills all of the criteria as a stem cell. These cells were found in the thick ascending limb of Henle's loop and exhibited clonogenicity, self-renewal, and multipotentiality with differentiation capacity into mesoderm and ectoderm progeny. Additionally, c-kit(+) cells formed spheres in nonadherent conditions when plated at clonal density and expressed markers of stem cells, progenitors, and differentiated cells. Ex vivo expanded c-kit(+) cells integrated into several compartments of the kidney, including tubules, vessels, and glomeruli, and contributed to functional and morphological improvement of the kidney following acute ischemia-reperfusion injury in rats. Together, these findings document a novel neonatal rat kidney c-kit(+) stem cell population that can be isolated, expanded, cloned, differentiated, and used for kidney repair following acute kidney injury. These cells have important biological and therapeutic implications. STEM Cells 2013;31:1644-1656

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BackgroundAnterior open bite occurs when there is a lack of vertical overlap of the upper and lower incisors. the aetiology is multifactorial including: oral habits, unfavourable growth patterns, enlarged lymphatic tissue with mouth breathing. Several treatments have been proposed to correct this malocclusion, but interventions are not supported by strong scientific evidence.ObjectivesThe aim of this systematic review was to evaluate orthodontic and orthopaedic treatments to correct anterior open bite in children.Search methodsThe following databases were searched: the Cochrane Oral Health Group's Trials Register (to 14 February 2014); the Cochrane Central Register of Controlled Trials (CENTRAL)(The Cochrane Library 2014, Issue 1); MEDLINE via OVID (1946 to 14 February 2014); EMBASE via OVID (1980 to 14 February 2014); LILACS via BIREME Virtual Health Library (1982 to 14 February 2014); BBO via BIREME Virtual Health Library (1980 to 14 February 2014); and SciELO (1997 to 14 February 2014). We searched for ongoing trials via ClinicalTrials.gov (to 14 February 2014). Chinese journals were handsearched and the bibliographies of papers were retrieved.Selection criteriaAll randomised or quasi-randomised controlled trials of orthodontic or orthopaedic treatments or both to correct anterior open bite in children.Data collection and analysisTwo review authors independently assessed the eligibility of all reports identified.Risk ratios (RRs) and corresponding 95% confidence intervals (CIs) were calculated for dichotomous data. the continuous data were expressed as described by the author.Main resultsThree randomised controlled trials were included comparing: effects of Frankel's function regulator-4 (FR-4) with lip-seal training versus no treatment; repelling-magnet splints versus bite-blocks; and palatal crib associated with high-pull chincup versus no treatment.The study comparing repelling-magnet splints versus bite-blocks could not be analysed because the authors interrupted the treatment earlier than planned due to side effects in four of ten patients.FR-4 associated with lip-seal training (RR = 0.02 (95% CI 0.00 to 0.38)) and removable palatal crib associated with high-pull chincup (RR = 0.23 (95% CI 0.11 to 0.48)) were able to correct anterior open bite.No study described: randomisation process, sample size calculation, there was not blinding in the cephalometric analysis and the two studies evaluated two interventions at the same time. These results should be therefore viewed with caution.Authors' conclusionsThere is weak evidence that the interventions FR-4 with lip-seal training and palatal crib associated with high-pull chincup are able to correct anterior open bite. Given that the trials included have potential bias, these results must be viewed with caution. Recommendations for clinical practice cannot be made based only on the results of these trials. More randomised controlled trials are needed to elucidate the interventions for treating anterior open bite.

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R. Zwiggelaar, S.M. Astley, C.J. Taylor and C.R.M. Boggis, 'Linear structures in mammographic images: detection and classification', IEEE Transaction on Medical Imaging 23 (9), 1077-1086 (2004)

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Binding, David; Couch, M.A.; Sujatha, K.S.; Webster, M.F., (2003) 'Experimental and numerical simulation of dough kneading in filled geometries', Journal of Food Engineering 58 pp.111-123 RAE2008

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High intensity focused ultrasound (HIFU) can be used to control bleeding, both from individual blood vessels as well as from gross damage to the capillary bed. This process, called acoustic hemostasis, is being studied in the hope that such a method would ultimately provide a lifesaving treatment during the so-called "golden hour", a brief grace period after a severe trauma in which prompt therapy can save the life of an injured person. Thermal effects play a major role in occlusion of small vessels and also appear to contribute to the sealing of punctures in major blood vessels. However, aggressive ultrasound-induced tissue heating can also impact healthy tissue and can lead to deleterious mechanical bioeffects. Moreover, the presence of vascularity can limit one’s ability to elevate the temperature of blood vessel walls owing to convective heat transport. In an effort to better understand the heating process in tissues with vascular structure we have developed a numerical simulation that couples models for ultrasound propagation, acoustic streaming, ultrasound heating and blood cooling in Newtonian viscous media. The 3-D simulation allows for the study of complicated biological structures and insonation geometries. We have also undertaken a series of in vitro experiments, in non-uniform flow-through tissue phantoms, designed to provide a ground truth verification of the model predictions. The calculated and measured results were compared over a range of values for insonation pressure, insonation time, and flow rate; we show good agreement between predictions and measurements. We then conducted a series of simulations that address two limiting problems of interest: hemostasis in small and large vessels. We employed realistic human tissue properties and considered more complex geometries. Results show that the heating pattern in and around a blood vessel is different for different vessel sizes, flow rates and for varying beam orientations relative to the flow axis. Complete occlusion and wall- puncture sealing are both possible depending on the exposure conditions. These results concur with prior clinical observations and may prove useful for planning of a more effective procedure in HIFU treatments.

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We introduce "BU-MIA," a Medical Image Analysis system that integrates various advanced chest image analysis methods for detection, estimation, segmentation, and registration. BU-MIA evaluates repeated computed tomography (CT) scans of the same patient to facilitate identification and evaluation of pulmonary nodules for interval growth. It provides a user-friendly graphical user interface with a number of interaction tools for development, evaluation, and validation of chest image analysis methods. The structures that BU-MIA processes include the thorax, lungs, and trachea, pulmonary structures, such as lobes, fissures, nodules, and vessels, and bones, such as sternum, vertebrae, and ribs.

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BACKGROUND: Breast cancer is a heterogeneous disease. Predictive biological markers (BM) of responsiveness to therapy need to be identified. Evaluation of BM is mainly done at the primary site. However, in the adjuvant therapy of breast cancer, the main goal is control of micrometastases. It is still unknown whether heterogeneity in the expression of BM between the primary site and its micrometastases exists. OBJECTIVE: To evaluate the expression of some BM with potential predictive value from the primary breast cancer site and metastatic ipsilateral axillary lymph nodes. PATIENTS AND METHODS: Focality (percentage of positive cells) and intensity staining scores were evaluated for each marker. Freshly cut sections (4 microm) from embedded blocks of breast cancer fixed in formalin or bouin were put onto superfrost slides (Menzel-Gläser). Protein expression was evaluated immunohistochemically (IHC) using monoclonal antibodies against: topo II-alpha (clone KiS1, 1 microg/ml, Roche) with a trypsine pre-treatment (P); HSP27 (clone G3.1, 1/60, Biogenex), HSP70 (clone BRM.22, 1/80, Biogenex) and HER2 (clone CB11, 1/40, Novocastra; without P); p53 (clone D07, 1/750, Dako) and bcl-2 (clone 124, 1/60, Dako) with citrate buffer as P. RESULTS: Overall, the percentage of discordant marker status in the primary tumour and its metastatic lymph nodes was 2% for HER2, 6% for p53, 15% for bcl-2, 19% for topoisomerase II-alpha, 24% for HSP27 and 30% for HSP70. For the subgroup of patients with positive BM in the primary tumour, the percentage of discordance was 6% for HER2, 7% for p53, 14% for bcl-2, 19% for HSP70, 21% for topoisomerase II-alpha and 36% for HSP27. For the subgroup of patients with positive BM in the lymph nodes, the percentage of discordance was 9% for bcl-2, 15% for HER2 and p53, 21% for topoisomerase II-alpha, 22% for HSP27 and 25% for HSP70. CONCLUSIONS: 1) No biological marker had 100% concordant results. 2) Although some discordant cases might be explained by the limitations of the IHC technique, future studies aiming to evaluate the predictive value of BM in the adjuvant therapy of breast cancer should take into account a possible difference in BM expression between the primary and the metastatic sites.

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BACKGROUND AND PURPOSE: Docetaxel is an active agent in the treatment of metastatic breast cancer. We evaluated the feasibility of docetaxel-based sequential and combination regimens as adjuvant therapies for patients with node-positive breast cancer. PATIENTS AND METHODS: Three consecutive groups of patients with node-positive breast cancer or locally-advanced disease, aged < or = 70 years, received one of the following regimens: a) sequential A-->T-->CMF: doxorubicin 75 mg/m2 q 3 weeks x 3, followed by docetaxel 100 mg/m2 q 3 weeks x 3, followed by i.v. CMF days 1 + 8 q 4 weeks x 3; b) sequential accelerated A-->T-->CMF: A and T were administered at the same doses q 2 weeks; c) combination therapy: doxorubicin 50 mg/m2 + docetaxel 75 mg/m2 q 3 weeks x 4, followed by CMF x 4. When indicated, radiotherapy was administered during or after CMF, and tamoxifen started after the end of CMF. RESULTS: Seventy-nine patients have been treated. Median age was 48 years. A 30% rate of early treatment discontinuation was observed in patients receiving the sequential accelerated therapy (23% during A-->T), due principally to severe skin toxicity. Median relative dose-intensity was 100% in the three treatment arms. The incidence of G3-G4 major toxicities by treated patients, was as follows: skin toxicity a: 5%; b: 27%; c: 0%; stomatitis a: 20%; b: 20%; c: 3%. The incidence of neutropenic fever was a: 30%; b: 13%; c: 48%. After a median follow-up of 18 months, no late toxicity has been reported. CONCLUSIONS: The accelerated sequential A-->T-->CMF treatment is not feasible due to an excess of skin toxicity. The sequential non accelerated and the combination regimens are feasible and under evaluation in a phase III trial of adjuvant therapy.

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BACKGROUND: Docetaxel has proven efficacy in metastatic breast cancer. In this pilot study, we explored the efficacy/feasibility of docetaxel-based sequential and combination regimens as adjuvant therapy of node-positive breast cancer. PATIENTS AND METHODS: From March 1996 till March 1998, four consecutive groups of patients with stages II and III breast cancer, aged < or = 70 years, received one of the following regimens: a) sequential Doxorubicin (A) --> Docetaxel (T) --> CMF (Cyclophosphamide+Methotrexate+5-Fluorouracil): A 75 mg/m q 3 wks x 3, followed by T100 mg/m2 q 3 wks x 3, followed by i.v. CMF Days 1+8 q 4 wks x 3; b) sequential accelerated A --> T --> CMF: A and T administered at the same doses q 2 wks with Lenograstin support; c) combination therapy: A 50 mg/m2 + T 75 mg/m2 q 3 wks x 4, followed by CMF x 4; d) sequential T --> A --> CMF: T and A, administered as in group a), with the reverse sequence. When indicated, radiotherapy was administered during or after CMF, and Tamoxifen after CMF. RESULTS: Ninety-three patients were treated. The median age was 48 years (29-66) and the median number of positive axillary nodes was 6 (1-25). Tumors were operable in 94% and locally advanced in 6% of cases. Pathological tumor size was >2 cm in 72% of cases. There were 21 relapses, (18 systemic, 3 locoregional) and 11 patients (12%) have died from disease progression. At median follow-up of 39 months (6-57), overall survival (OS) was 87% (95% CI, 79-94%) and disease-free survival (DFS) was 76% (95% CI, 67%-85%). CONCLUSION: The efficacy of these docetaxel-based regimens, in terms of OS and DFS, appears to be at least as good as standard anthracycline-based adjuvant chemotherapy (CT), in similar high-risk patient populations.