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991.
人类皮下和网膜脂肪组织中脂联素基因的表达和调控的研究 总被引:4,自引:0,他引:4
目标:探讨脂联素在人类皮下和网膜脂肪组织中mRNA表达水平,以及糖皮质激素和PPARγ激动剂对脂联素的调控作用。方法:应用real-time摇RT-PCR方法观察了16名成人腹部皮下和网膜脂肪组织中脂联素mRNA表达水平以及与肥胖的关系。通过体外培养,观察地塞米松(dexamethasone,DEX)和/或PPARγ激动剂(troglitazone,TGZ)对不同部位脂肪组织脂联素的表达和分泌的调控作用。结果:皮下和网膜脂肪组织脂联素mRNA表达丰富但无显著部位差异,网膜脂肪组织脂联素mRNA水平与BMI呈显著负相关(r=0.56,P<0.05)。体外培养24h后,TGZ处理组脂肪组织脂联素基因的表达明显增加(皮下:70%;网膜:102%),且网膜脂肪组织脂联素的分泌明显高于对照组(P<0.05);DEX则下调网膜脂肪组织脂联素mRNA的表达水平36%,TGZ可逆转这种抑制作用。结论:网膜脂肪组织中脂联素mRNA的表达随BMI增加而下降,并受到糖皮质激素及PPARγ激动剂调控。脂联素的部位特异性表达和调控可能是内脏型肥胖连接胰岛素抵抗的重要分子机制。 相似文献
992.
Agustina Heredia-Martinez Guillermo Rosa-Diez Jorge R. Ferraris Anna-Karin Sohlenius-Sternbeck Carina Nihlen Annika Olsson Jon O. Lundberg Eddie Weitzberg Mattias Carlstrm Rafael T. Krmar 《Nutrients》2022,14(12)
Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity. 相似文献
993.
急性白血病完全缓解后患乳腺癌1例 总被引:1,自引:0,他引:1
1 病例报告女,51岁. 因发热、关节疼痛、齿龈胀痛、左下肺感染20 d,抗生素治疗无效,于2001-11-29入我院血液科治疗. 查体:T 37.5℃,P 120次/min,R 18次/min,BP 110/50 kPa,贫血外观,巩膜无黄染,皮肤黏膜无出血,右颌下可触及一黄豆粒大小淋巴结,触痛(±),胸骨压痛( ),心率120次/min,律齐,无病理性杂音. 双肺未闻及干湿啰音. 腹软,肝脾未触及,四肢运动正常. 既往史:曾于1992年行"乳腺小叶切除术",1999年因子宫肌瘤行"子宫次全切除术". 家族史:其姐姐1982年患乳腺癌,因肺转移已于1983年病故. 相似文献
994.
银杏叶提取物改善反复脑缺血再灌注小鼠血液流变学的作用 总被引:34,自引:0,他引:34
目的:研究银杏叶提取物(EGB)改善反复脑缺血再灌注小鼠血液流这的作用。方法:采用反复脑缺血再注模型鼠,应用毛细管微量热沉法和毛细管微量法分别检测血纤维蛋白原含量和红细胞压积数值,并将结果输入全自动血液流变仪得出血浆粘度、血液粘度、血细胞聚集系数,血栓形成系数及微循环滞留时间(MST)。结果:EBG25 ̄100mg/kg均可不同程度地降低Fib、HCT、降低ηb、ηp、ηh,缩小VAL及TWEL, 相似文献
995.
Jernström HC Johannsson OT Loman N Borg A Olsson H 《Breast cancer research and treatment》1999,58(3):293-299
Background: An early age at menarche, a short menstrual cycle length, and a high age at first full term pregnancy or nulliparity are known risk factors for breast cancer. These risk factors have previously been reported to differ between breast cancer patients with and without a family history of breast cancer and also between breast cancer patients and controls.
Methods: Self-administered questionnaires were filled out by 95 women belonging to 24 families with known BRCA1 mutations, 16 women belonging to nine families with known BRCA2 mutations, and 95 women belonging to 65 families with hereditary breast cancer where no BRCA1 or BRCA2 mutations could be detected. Thirty-nine women were BRCA1 mutation carriers and 56 women were BRCA1 negative, 11 women were BRCA2 carriers and five BRCA2 negative. All women were born between 1905 and 1979.
Results: Age at menarche, physiological menstrual cycle length at age 30 or at current age in younger women (when not using oral contraceptives), age at first full term pregnancy, and nulliparity did not significantly differ between BRCA1 mutation carriers and BRCA1 negative women. Too few women were BRCA2 negative to serve as a control group. BRCA2 mutation carriers were therefore compared with BRCA1 negative and BRCA2 negative women. None of the above reproductive factors did significantly differ between BRCA2 mutation carriers and from BRCA1 and BRCA2 families. Women from non-BRCA1/BRCA2 hereditary breast cancer families had a higher age at menarche, but this was no longer significant after adjustment for other factors in a multivariate model.
Conclusion: Our results suggest that reproductive risk factors of breast cancer are not related to BRCA1 or BRCA2 carrier status. There was also no indication that these factors differ in carriers of unknown susceptibility genes compared with non-carriers from BRCA1 and BRCA2 families. 相似文献
996.
A monoclonal antibody (designated K:1-6F) generated by hybridization of mouse myeloma cells with spleen cells from mice immunized with the erythroleukemic cell line K562 was found by fluorescence-activated cell sorter analysis, dot-blot assay and electroimmunoblotting to bind to a majority of cells in the K562 and HEL erythroleukemic cell lines, to a subset of cells of the erythroid lineage from normal bone marrow, to a subset of cells in all analysed cases (total 10) of erythroleukemia, and weakly to cells from patients with myeloid leukemia. The antibody did not bind to normal erythrocytes, monocytes, T- and B lymphocytes or granulocytes, as well as a panel of human malignant cell lines of hemopoietic origin (HL60, U937, Daudi, Molt-3, RH-L4 and U266). Biochemical characterization of the antigen defined by the antibody suggests that eht epitope is defined by a carbohydrate structure alone or in combination with proteins. Four molecules with Mr 100 kD, 65 kD, 45 kD and 18 kD respectively were immunoprecipitated from Triton X-100 extract of K562 erythroleukemia cells. Neuraminidase did not affect the binding of the antibody, whereas tunicamycin reduced the K:1-6F expression. The K:1-6F Mab was in normal bone marrow found to be specific for erythroid precursor cells and may therefore be useful in examination of normal and leukemic erythropoiesis. 相似文献
997.
Pierre Carmona Christian von Corswant Magnus Rding Aila Srkk Eva Olsson Niklas Lorn 《RSC advances》2022,12(40):26078
Porous phase-separated ethylcellulose/hydroxypropylcellulose (EC/HPC) films are used to control drug transport out of pharmaceutical pellets. The films are applied on the pellets using fluidized bed spraying. The drug transport rate is determined by the structure of the porous films that are formed as the water-soluble HPC leaches out. However, a detailed understanding of the evolution of the phase-separated structure during production is lacking. Here, we have investigated EC/HPC films produced by spin-coating, which mimics the industrial manufacturing process. This work aimed to understand the structure formation and film shrinkage during solvent evaporation. The cross-sectional structure evolution was characterized using confocal laser scanning microscopy (CLSM), profilometry and image analysis. The effect of the EC/HPC ratio on the cross-sectional structure evolution was investigated. During shrinkage of the film, the phase-separated structure undergoes a transition from 3D to nearly 2D structure evolution along the surface. This transition appears when the typical length scale of the phase-separated structure is on the order of the thickness of the film. This was particularly pronounced for the bicontinuous systems. The shrinkage rate was found to be independent of the EC/HPC ratio, while the initial and final film thickness increased with increasing HPC fraction. A new method to estimate part of the binodal curve in the ternary phase diagram for EC/HPC in ethanol has been developed. The findings of this work provide a good understanding of the mechanisms responsible for the morphology development and allow tailoring of thin EC/HPC films structure for controlled drug release.The EC/HPC/EtOH phase diagram could be estimated from the CLSM monitoring of the cross-sectional in situ phase separation. The findings of this work provide a good understanding of the structure evolution. 相似文献
998.
Arnar Geirsson Kayoko Shioda Christian Olsson Anders Ahlsson Jarmo Gunn Emma C. Hansson Vibeke Hjortdal Anders Jeppsson Ari Mennander Anders Wickbom Igor Zindovic Tomas Gudbjartsson 《The Journal of thoracic and cardiovascular surgery》2019,157(5):1750-1758
Objectives
Open-distal anastomosis is the preferred technique over clamp-on technique for surgical repair of acute type A aortic dissection (ATAAD). The aim of this study was to define how outcomes of ATAAD were affected by the use of either technique.Methods
Nordic Consortium for Acute Type A Aortic Dissection includes 8 academic cardiothoracic hospitals in 4 Nordic countries. The cohort consisted of 1134 patients, 153 clamp-on and 981 open-distal, from 2005 to 2014.Results
Patients who underwent operation with the clamp-on were younger, more frequently had coronary artery disease, bicuspid aortic valve, hypotension/shock or syncope, and a greater PennClass than open-distal patients. Postoperative cerebral vascular accident occurred less frequently in clamp-on (14/153, 10%) compared with the open-distal group (190/981, 20%). Clamp-on had greater 30-day mortality (39/153, 25%) than the open-distal group (158/981, 16%), and 5-year survival was also worse in clamp-on (61.8% ± 4.4%) compared with the open-distal group (73.0% ± 1.6%). The open-distal technique was used more frequently in greater-volume hospitals but was not independently associated with 30-day mortality. Preoperative condition was an independent risk factor whereas hospital volume and later year of operation were beneficial in regard to short-term outcome. Open-distal was independently associated with improved mid-term survival.Conclusions
Patients who underwent operation with the clamp-on were sicker on presentation and had worse short- and mid-term survival compared with the open-distal group. Patients in the open-distal group had greater rates of cerebrovascular complications. The results support the routine use of open-distal anastomosis as the primary operative strategy for ATAAD, although clamp-on can be performed successfully in select cases. 相似文献999.
1000.
Peter Alping MD Johan Askling MD Joachim Burman MD Katharina Fink MD Anna Fogdell-Hahn PhD Martin Gunnarsson MD Jan Hillert MD Annette Langer-Gould MD Jan Lycke MD Petra Nilsson MD Jonatan Salzer MD Anders Svenningsson MD Magnus Vrethem MD Tomas Olsson MD Fredrik Piehl MD Thomas Frisell PhD 《Annals of neurology》2020,87(5):688-699