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991.
Francesco Solimene MD Mario Giannotti Santoro MD Antonio De Simone MD Maurizio Malacrida MSc Giuseppe Stabile MD Claudio Pandozi MD Gemma Pelargonio PhD MD Filippo Maria Cauti MD Marco Scaglione MD Domenico Pecora MD Maria Grazia Bongiorni MD Alberto Arestia MD Gabriella Grimaldi MD Maurizio Russo MD Maria Lucia Narducci PhD MD Luca Segreti MD 《Journal of cardiovascular electrophysiology》2021,32(6):1540-1548
992.
以生物电阻法检测的身体组成成分与女性骨量的关系 总被引:4,自引:0,他引:4
目的 探讨体内的体脂和非体脂对绝经前和绝经后妇女骨密度(BMD)的作用。方法 282例绝经前和205例绝经后妇女参加本研究,用双能X线骨密度仪测定腰椎和股骨颈BMD,用生物电阻法测定体脂和非体脂,同时测量身高、体重、腰围、臀围,并计算体重指数(BMI)和腰臀围比(WHR)。结果 体脂和非体脂与绝经前、绝经后妇女腰椎和股骨颈BMD均呈显著正相关(P<0.01),多元逐步回归分析显示,在绝经前妇女中,非体脂和年龄是腰椎BMD的独立影响因素(R^2=0.077,P=0.000),非体脂、年龄和BMI是影响股骨颈BMD的决定因素(R^2=0.130,P=0.000),在绝经后妇女中,体脂和年龄是影响腰椎和股骨颈BMD的决定因素(R^2分别为0.153和0.184,P=0.000)。结论 体脂和非体脂对绝经前和绝经后妇女BMD的作用不同,非体脂是决定绝经前妇女骨量的重要因素,而体脂是影响绝经后妇女骨量的重要因素。 相似文献
993.
Summary For 2 years bone density changes in patients with rheumatoid arthritis were monitored to determine the effect of low dose corticosteroid treatment. Sixteen berimenopausal females were studied. Of these nine were treated with 5 to 20 mg prednisone per day and seven had no steroids. The differential effects on trabecular bone density and on cortical bone in the radius and the tibia were examined with high precision peripheral quantitative computed tomography (QCT). Steroid therapy did hot influence cortical bone loss and had only a minor influence on trabecular bone density. Of greater importance was the influence of estrogen depletion. Corticosteroids and estrogen depletion, however, cannot explain fully the yearly loss of 5.7% in the trabecular and 4% in the cortical bone of the radius. 相似文献
994.
Heinz H. Fiebig Dietmar P. Berger Karin Köpping Harry C. J. Ottenheijm Zbigniew Zylicz 《Journal of cancer research and clinical oncology》1990,116(6):550-556
Summary The colony formation in agar of human tumor xenografts, of murine tumors and of human bone marrow was used as a test system to determine the in vitro activity of the two novel cytostatic agents, mitozolomide and sparsomycin. Mitozolomide was additionally studied in vivo in nine human tumor xenografts. The comparison of in vitro/in vivo activity allows an assessment of the relevant in vitro dose based on in vivo pharmacological behavior of a compound. Both compounds showed clear dose/response effects in vitro. A dose of 3 g/ml mitozolomide, given by continuous exposure, was active (colony number of test <30% of the control group) in 12/42 (29%) human tumor xenografts as well as in the four murine tumors, P388, L1210, B16 melanoma and colon carcinoma 38, whereas the two human bone marrows showed no significant suppression of the ability to form colonies in culture. The comparison of in vitro with in vivo activity suggests that the in vitro dose of 3 g/ml corresponds best to the activity observed in animal experiments. The highest activity was observed in small-cell cancer of the lung (4/5), followed by melanomas (2/7) and non-small-cell cancer of the lung (2/9). Furthermore, activity was found in a cancer of the large bowel, stomach, breast and in one sarcoma. In the treatment of nine human tumor xenografts growing subcutaneously in nude mice, mitozolomide effected a complete or partial remission in 6 out of 9 tumors. In comparison to standard drugs mitozolomide is one of the most effective compounds in these tumors. These data indicate that mitozolomide possesses potent broad-spectrum activity in human tumor xenografts. Sparsomycin (0.1 g/ml, continuous exposure) was active in 11/46 (24%) human tumor xenografts and in 4/5 of the murine tumors, whereas the colony-forming capacity of four human bone-marrows showed no inhibition, suggesting that this dose level may be the relevant in vitro dose. However, the high in vitro activity in murine tumors is incompatible with the in vivo activity. In mice the only responsive tumor was leukemia P388, whereas the L1210, B16 melanoma and colon carcinoma 38 were resistant. At the dose level of 0.03 g/ml only 3/30 (10%) of the human tumor xenografts were sensitive. In an earlier clinical phase I study the dose-limiting adverse effect was eye toxicity and not bone-marrow suppression. This example illustrates that comparing in vitro with in vivo activity in the same tumor results in a more reliable estimation of the relevant in vitro dose than does comparing in vitro activity with in vitro effects on human bone marrow.Abbreviations Mitozolomide
8-carbamoyl-3-(2-chloroethyl)imidazo(5,1-d)-1,2,3,5-tetrazin-4(3H)-one
- NSC 353451
formerly known as azolastone
- sparsomycin
NSC 59 729
- DTIC
5-(3,3-dimethyltriazen-1-yl)-imidazole-4-carboxamide
- MTIC
5-(3-methyltriazen-1-yl)imidazole-4-carboxamide
- DMSO
dimethylsulfoxide
Dedicated to Professor Dr. D. Schmähl, Heidelberg, on the occasion of his 65th birthday 相似文献
995.
目的 观察狼疮肾炎(LN)长期泼尼松治疗后骨矿含量及骨代谢生化指标的变化。方法 研究对象为女性,健康对照A组20例,患者组25例(肾功能正常),于泼尼松治疗前(B),治疗后2个月,4个月分别用双能X线骨密度仪测定相关部位骨密度,同时测定空腹血钙,磷,碱性磷酸酶,甲状旁腺激素(PTH-M),骨钙素(BGP)及其他生化指标。结果:(1)LN治疗前组除腰2外各部分骨密度与对照组差异无显著性(P>0.05)。泼尼松治疗后2个月骨密度无明显变化,治疗4个月时桡骨骨密度较治疗前下降(P<0.01)。(2)患者治疗后2个月,4个月血钙,磷,碱性磷酸酶无明显变化,血PTH均较治疗前上升(P<0.01),血BGP均较治疗前下降(P<0.01)。结论 (1)狼疮肾炎长期泼尼松治疗后各部位骨密度逐渐下降,桡骨骨密度较早发生改变。(2)泼尼松治疗后血BGP下降,PTH上升,血BGP和PTH是反映继发性骨量减少的 敏感性生化指标,较骨形态学改变早。 相似文献
996.
M. Salzer-Kuntschik 《Journal of cancer research and clinical oncology》1981,101(2):171-176
Summary Report of a case of clear-cell chondrosarcoma at the upper end of the left femur of a 32-year-old woman. She had two pathologic fractures during a period of 4 years. After the first fracture an excochleation and after the second fracture a resection were done. Two years after resection she had no local recurrence and was free from metastasis. 相似文献
997.
There is still debate on whether inflammatory pseudotumor should be considered benign or malignant. This lesion has only been reported twice in bone, apart from cases complicating foreign body reaction to joint replacement arthroplasty. We report here a third case, localized at the sacrum. A 31-year-old man had inflammatory dorsalgia and polyarthralgia without synovitis but with fever, asthenia, and erythema nodosa. Biological tests and X-rays were not informative, but technetium scintigraphy revealed a high level of left sacroiliac tracer binding. Several nonsteroidal anti-inflammatory drugs and sulfasalazine treatment were given over 3 months but ineffective. Pelvic magnetic resonance imaging showed an osteolytic tumor of the sacrum. Biopsy suggested a malignant fibrosarcoma, but complete evaluation after surgical resection demonstrated an inflammatory pseudotumor. All clinical symptoms disappeared within a few days after surgery, which is suggestive of a paraneoplastic syndrome. No relapse has occurred after 4 years. 相似文献
998.
In historical cases, ancient DNA investigations and missing persons identification, teeth or bone samples are often the only and almost always the best biological material available for DNA typing. On the other hand, DNA obtained from bone material may be characterized by a high degradation index (DI) or its low content, or DNA tests cannot be repeated due to bone piece size limitation. That is often the effect of the environment in which the material was placed and the time during which exposure to unfavorable environmental factors took place. Therefore, it is very important to use appropriate procedures related to STR analysis. For our study, we selected 80 challenging bone samples. The amount of DNA was compared in qPCR using Quantifiler™ Trio DNA Quantification Kit and Investigator® Quantiplex® Pro RGQ. All qPCR results were confirmed by PCR-CE. The results of DNA concentrations and the assigned degradation index (DI) differed significantly within analyzed samples (~10%). Additionally, the Y-chromosome DI also differed from the autosomal DI in the samples. The difference in degradation indexes could explain the lower Y-chromosome amplification success rate compared to autosomal e.g. during human identification process. The results indicate that performing two DNA quantifications with the use of two different kits (primers sets) allows for a much more precise evaluation of the DNA quality and quantity in the isolate. We suggest that at least one of two suggested DNA concentration measurements should be based on an additional determination of the Y chromosome degradation index. Altogether, it allows for rational isolate management, especially when the volume is limited and the sample is unique. 相似文献
999.
1000.
骨质疏松性骨折愈合缓慢,预后差。募集的巨噬细胞极化为促炎M1型巨噬细胞及抑炎M2型巨噬细胞,两种亚型的动态平衡影响骨折愈合速度和预后。但在原发性骨质疏松性骨折及继发性骨质疏松性骨折中,M1型和M2型巨噬细胞极化失衡,严重影响骨折愈合。研究表明,通过一些生物学方法重建巨噬细胞极化平衡,如生物医用仿生材料和外泌体携载miRNA治疗等,可有效改善巨噬细胞表型极化,减少骨吸收,促进成骨分化,加速骨质疏松性骨折骨愈合。因此,笔者从巨噬细胞在骨折愈合过程中的作用、巨噬细胞极化失衡导致骨质疏松性骨折延迟愈合及重建巨噬细胞极化平衡加速骨质疏松性骨折骨愈合等方面,就巨噬细胞对骨质疏松性骨折骨愈合影响的研究进展进行综述,为临床治疗骨质疏松性骨折提供新的思路。 相似文献