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排序方式: 共有1257条查询结果,搜索用时 15 毫秒
1.
Rena Fushiki Kotoe Mayahara Mai Ogawa Yasuyo Takahashi Yoko Karasawa Niina Tsurumachi 《Connective tissue research》2015,56(4):336-341
Purpose: Orthodontic tooth movement occurs during the bone remodeling induced by therapeutic mechanical strain. It is important to investigate the relation between the strength of mechanical stress and bone formation activity. The aim of this study was to determine the effect of high-magnitude mechanical strain on bone formation in detail.Materials and methods: Osteoblast-like cells isolated from fetal rat calvariae were loaded with 18% cyclic tension force (TF) for 48?h. To phenotypically investigate the effect of TF, we measured the number and the size of bone nodules stained by von Kossa technique on day 21 after cell seeding and determined the calcium content of bone nodules on day 14. Furthermore, we examined the gene expression of BMP-2, Runx2 and Msx2, which are important factors for bone nodule formation, on days 1, 4 and 7 after TF loading.Results: The maximum bone nodule size in the control group was 1620 and 719?μm in the TF group. Furthermore, the mean number of bone nodules sized over 360?μm in the TF group was significantly decreased compared to the control group. The calcium content was also significantly decreased to 42% by TF loading. The mRNA expression of BMP-2, Runx2 and Msx2 was decreased 1 and 4 days after TF loading.Conclusion: The differentiation of bone forming progenitor cells into bone nodule forming cells was inhibited by TF due to the decreased expression of bone formation related factors such as BMP-2, Runx2 and Msx2. 相似文献
2.
目的 为规范化种植盐生肉苁蓉药材的质量研究提供基础研究资料。 方法 选择 RP-HPLC 建立盐生肉苁蓉补肾助阳功能特征成分的指纹图谱,并进行栽培品与野生品、不同生长期、不同药用部位指纹图谱的比较研究,采用计算机辅助相似度评价软件分析了相似度。 结果 种植基地药材的指纹图谱具有较高的相似度,其化学组成相似,相对比例也基本稳定。不同生长期和不同部位药材的指纹图谱也具有较好的一致性,但特征峰的含量存在明显差异。 结论 利用 RP-HPLC 指纹图谱可以较为全面地反映盐生肉苁蓉补肾助阳功能整体特征成分的内在质量,方法重现性好。 相似文献
3.
目的 评价不同剂量景天通脉方对动脉粥样硬化斑块的抑制作用。方法 健康新西兰兔54只随机分为:正常对照组, 高胆固醇组(模型组), 血脂康组, 景天通脉方小、中、大剂量组, 共6组;除正常对照组外,其余大鼠采用高胆固醇饲料并免疫损伤诱发的动脉粥样硬化斑块模型, 观察各组血脂和C-反应蛋白(CRP)以及主动脉斑块/内膜面积比、内/中膜厚度比等并比较。结果 对血脂的影响:模型组与正常对照组比较,血清总胆固醇(TC)、 甘油三酯(TG)及低密度脂蛋白胆固醇(LDL-C)均升高, 差异均有统计学意义(P<0.05);血脂康组及景天通脉方小、中、大剂量组TC、LDL-C均明显低于模型组(P<0.05), 景天通脉方中剂量组明显低于小、大剂量组及血脂康组(P<0.05);TG景天通脉方小、中、大剂量组及血脂康组与模型组比较差异无统计学意义(P>0.05);而高密度脂蛋白胆固醇(HDL-C)景天通脉方大剂量组、血脂康组高于景天通脉方小、中剂量组, 正常对照组和模型组(P<0.05)。对CRP的影响:模型组明显高于正常对照组(P<0.05), 景天通脉方3组、正常对照组、血脂康组间比较差异均无统计学意义(P>0.05)。 正常对照组无斑块和内、中膜增厚, 景天通脉方组与模型组比较, 斑块面积、内膜厚度、中膜厚度、斑块/内膜面积比、内/中膜厚度比均明显下降(P<0.05), 景天通脉方中剂量组明显低于小、大剂量组及血脂康组(P<0.05)。结论 景天通脉方具有抑制动脉粥样硬化的作用, 可能是通过调脂、抗炎作用来完成,效应以中剂量(人的等效剂量)为佳。 相似文献
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Ottavio Rena Esther Papalia Alberto Oliaro PierLuigi Filosso Enrico Ruffini Giuliano Maggi Caterina Casadio 《European journal of cardio-thoracic surgery》2006,30(2):217-222
OBJECTIVE: Development of distant metastases is one of the primary characteristics of malignant tumours. During the last decades, lung metastasectomy has been progressively accepted as a therapeutic option in oncology patients. The present paper aims to evaluate the long-term results and factors influencing prognosis in patients submitted to lung resection for metastases from extrapulmonary epithelial tumours. METHODS: We retrospectively analysed data of 202 patients undergoing 207 procedures of lung metastasectomy between January 1980 and December 2003. Factors that may influence long-term prognosis such as completeness of resection, histology of the tumour, disease-free interval, number of resected lesions, involvement of hilar or mediastinal lymph nodes, systemic treatments were investigated. RESULTS: Complete resection was carried out in 169 patients (83.7%). The more frequent lung resection was sublobar in 67.6% of cases, but rarely in selected patients bilobectomy or pneumonectomy has been carried out too. Perioperative morbidity and mortality were 7.7% and 0.9%. Mean disease-free interval was 49+/-48 months. Mean follow-up was 33+/-31 months, 5-year and 10-year survival rates for completely resected patients were 43% and 17%, respectively. By univariate and multivariate analyses, completeness of resection, disease-free interval of 36 months or more, and single resected metastasis were found to be significant prognostic factors. CONCLUSIONS: Resection of epithelial lung metastases allows an acceptable prognostic result in appropriately selected patients with very low perioperative morbidity and mortality. Factors such as high disease-free interval, single metastasis and completeness of resection are demonstrated and confirmed to be significantly associated with long-term survival. 相似文献
7.
Rena K. Fox 《Current hepatitis reports》2003,2(3):116-124
Observational and some experimental data suggest that hepatitis C virus can manifest in a variety of disease processes outside
the liver. The links between hepatitis C virus and membranoproliferative glomerulonephropathy, porphyria cutanea tarda, lichen
planus, cryoglobulinemia, diabetes mellitus, B-cell non-Hodgkin’s lymphoma, and thyroiditis are critically reviewed. Based
on the available evidence, recommendations for the clinical approach to patients with extrahepatic diseases are discussed. 相似文献
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Casas KA Mononen TK Mikail CN Hassed SJ Li S Mulvihill JJ Lin HJ Falk RE 《American journal of medical genetics. Part A》2004,(4):331-339
We report a new patient with terminal deletion of chromosome 2 with breakpoint at 2q36 and five additional new patients with 2q terminal deletion with breakpoint at 2q37. Hemidiaphragmatic hernia is a novel finding in one patient with a breakpoint at 2q37.1. In comparing these patients to 60 previously reported individuals with 2q terminal deletions, certain physical abnormalities are loosely associated with positions of breakpoint. For example, facial features (e.g., prominent forehead, depressed nasal bridge, and dysmorphic ears and nose), short stature, and short hands and feet were frequent in patients with breakpoints at or proximal to 2q37.3. Reports of horseshoe kidney and Wilms tumor were limited to patients with a breakpoint at 2q37.1, and structural brain anomalies and tracheal anomalies were reported only in patients with breakpoints at or proximal to 2q37.1. Cleft palate was reported only in patients with the most proximal breakpoints (2q36 or 2q35). Neurological effects including developmental delay, mental retardation, autistic-like behavior, and hypotonia were typical in this patient population but did not stratify in severity according to breakpoint. Terminal deletion of the long arm of chromosome 2 should be considered in the infant with marked hypotonia, poor feeding, gastroesophageal reflux, and growth delay, and the older child with developmental delay, autistic behavior, and the characteristic facial and integumentary features described herein. Assignment of clinical features to specific breakpoints and refinement of predictive value may be useful in counseling. 相似文献
10.
Lyashchenko K Whelan AO Greenwald R Pollock JM Andersen P Hewinson RG Vordermeier HM 《Infection and immunity》2004,72(5):2462-2467
Vaccine development and our understanding of the pathology of bovine tuberculosis in cattle would be greatly facilitated by definition of the immunological correlates of protection and/or pathology. In this study we analyzed humoral immune responses in Mycobacterium bovis BCG-vaccinated and control cattle (in particular, the relationship between the intradermal comparative tuberculin skin test and serum immunoglobulin G [IgG] responses) against a range of mycobacterial antigens (MPB59, MPB64, MPB70, MPB83, ESAT-6, CFP-10, Acr1, and PstS-1) by multiantigen print immunoassay and conventional enzyme-linked immunosorbent assay. Following M. bovis infection, the comparative tuberculin skin test strongly boosted IgG, IgG1, and IgG2 antibody responses, particularly against MPB83 and MPB70, in unvaccinated cattle but failed to boost these responses, or did so only weakly, in BCG-vaccinated calves. In addition, the skin test-induced increases in MPB83-specific IgG responses correlated positively with bacterial loads and ESAT-6-induced in vitro gamma interferon responses. In conclusion, both the negative correlation of skin test-enhanced MPB83-specific antibody responses with BCG-induced protection and their positive correlation with bacterial loads can serve as useful markers for vaccine efficacy after challenge. 相似文献