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排序方式: 共有4178条查询结果,搜索用时 15 毫秒
21.
Nakabayashi T Sakata KM Sakata A Kong L Lau CA Letterio JJ Vela-Roch N Talal N Dang H 《Inflammation》2001,25(2):69-73
The TGF-1(–/–) mouse is a murine model for systemic autoimmune disease. The aim of this study is to elucidate the immunological mechanism that leads to multifocal tissue inflammation and autoantibody production in TGF-1(–/–) mice. Heart, lung, liver, and salivary gland from TGF-1(–/–) were assessed for CD154 expression by RT-PCR and immunohistochemistry. Compared to wild-type littermates, CD154 expression was elevated in all tissues studied. Furthermore, IL-12 mRNA was expressed in the salivary gland and heart of TGF-1(–/–) mice and not in wild-type littermates. This suggests that the CD154 pathway is activated in these tissues. This shows that TGF-1 regulates CD154 expression leading to spontaneous IL-12 production and autoimmunity. 相似文献
22.
桡神经及其深支的血供 总被引:1,自引:0,他引:1
在25具成人尸体(50例)上,观测了桡神经及其深支的血供。桡神经的营养动脉平均为4.36±0.26支,营养动脉和来源动脉的外径平均为0.38±0.08mm和1.65±0.05mm。桡神经深支的营养动脉平均为1.72±0.16支,营养动脉和来源动脉的外径平均为0.29±0.01mm和1.91±0.07mm。 相似文献
23.
El Benna J Hayem G Dang PM Fay M Chollet-Martin S Elbim C Meyer O Gougerot-Pocidalo MA 《Inflammation》2002,26(6):273-278
Superoxide anion (O2°-)production by neutrophil NADPH oxidase participates in arthritic joint lesion formation. Proinflammatory cytokines such as tumor necrosis factor (TNF), interleukin 8 (IL-8) and granulocyte/macrophage-colony stimulating factor (GM-CSF) have a priming effect on neutrophil NADPH oxidase activity. NADPH oxidase activation is dependent on phosphorylation of p47phox, a cytosolic component of the enzyme. We studied O2°-production and p47phox phosphorylation in synovial fluid (SF) from patients with rheumatoid arthritis (RA) and spondylarthropathy (SpA) according to TNF, IL-8 and GM-CSF levels. O2°-production by neutrophils isolated from SF of all the arthritis patients (RA and SpA) was higher than that of circulating resting neutrophils and when stimulated with fMLP or PMA. In addition, p47phox was partially phosphorylated in SF neutrophils compared to circulating neutrophils. High levels of TNF and IL-8 (but not GM-CSF) are detected in patient's SF (compared to circulating blood levels). TNF levels were significantly higher in RA than in SpA SF. These results suggest that increased NADPH oxidase activity could be involved in arthritic joint inflammation through increased p47phox phosphorylation. This could be the result of the presence of high levels of priming agents such as TNF and IL-8 but not GM-CSF. 相似文献
24.
大鼠孤束核内5-HT能纤维和终末与向臂旁核投射的NOS阳性神经元的联系 总被引:3,自引:0,他引:3
应用四甲基罗达明逆行标记和免疫荧光技术相结合 ,在激光扫描共聚焦显微镜下对大鼠孤束核内 5 -HT能纤维和终末与向臂旁核投射的 NOS阳性神经元之间的联系进行了观察。将四甲基罗达明注入一侧外侧臂旁核后可见孤束核尾段背内侧、胶质、小细胞、内侧、中间内侧等亚核和连合亚核内出现较多的逆标神经元 ,四甲基罗达明逆标和 NOS阳性神经元以及 5 -HT阳性终末重叠分布 ,其中四甲基罗达明和 NOS双重阳性神经元分别占四甲基罗达明逆标和 NOS阳性神经元总数的 8.3% ( 14 /16 8)和 18.4% ( 14 /76 )。在此 5 -HT样阳性纤维和终末包绕着 NOS阳性神经元、四甲基罗达明逆标神经元及四甲基罗达明和一氧化氮合酶双重阳性神经元的胞体和树突 ,形成点状紧密接触。本研究结果提示 ,孤束核内来自下行性抑制系统的 5 -HT能纤维和终末可能与向臂旁核投射的 NOS阳性神经元形成突触联系 ,从而可对 NOS阳性神经元所传递的包括伤害性信息在内的内脏感觉传入信息发挥抑制性调控作用 相似文献
25.
A 71 year-old woman with a large tumor of the upper lobe of the left lung was diagnosed as having metastatic adrenal cortical carcinoma nine years after the initial adrenalo-nephrectomy. The patient was well with no recurrence for six years following resection of the single lung metastasis. 相似文献
26.
Some effects of urease administration on laboratory animals 总被引:2,自引:0,他引:2
27.
28.
Bischoff FZ Sinacori MK Dang DD Marquez-Do D Horne C Lewis DE Simpson JL 《Human reproduction update》2002,8(6):493-500
Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development. 相似文献
29.
骨髓神经组织定向干细胞的分离培养鉴定 总被引:2,自引:2,他引:2
目的:为临床中枢神经系统疾患的细胞移植及组织工程修复周围神经提供一种应用广泛、可来源于自体、无免疫排斥和伦理道德等问题的移植用种子细胞。方法:采用DMEM/F12(1∶1)无血清神经干细胞培养液,通过先贴壁、后悬浮的方法从大鼠骨髓中分离、培养单克隆生长的神经组织定向干细胞(neural tissue-committed stem cells,NTC-SCs),通过免疫细胞化学检测NTCSCs细胞球CXCR4和Nestin蛋白,以及细胞球自然分化后神经元β-TublinⅢ、MAP2ab以及神经胶质细胞CNPase、GFAP等蛋白的表达。结果:NTCSCs细胞球表达神经干细胞标志蛋白Nestin和组织定向干细胞标志蛋白CXCR4;NTCSCs细胞球在含15%胎牛血清的DMEM培养液中可自然分化,免疫荧光显示神经元和神经胶质蛋白β-TublinⅢ、MAP2ab、CNPase、GFAP等标志物阳性。结论:本研究提供了一种操作简便、成本低廉的NTCSCs的分离培养方法,NTCSCs作为种子细胞为脑、脊髓等神经系统疾患和创伤的修复和治疗提供了广阔的应用前景。 相似文献
30.
Suraj Suresh Mohammad Siddiqui Mouhanna Abu Ghanimeh Jessica Jou Stephen Simmer Vivek Mendiratta Sarah Russell Mustafa Al-Shammari Abigail Chatfield Eva Alsheik Duyen Dang Jeffrey Genaw Tobias Zuchelli 《Obesity research & clinical practice》2021,15(2):172-176
BackgroundAlthough recent studies have shown an association between obesity and adverse coronavirus disease 2019 (COVID-19) patient outcomes, there is a paucity in large studies focusing on hospitalized patients. We aimed to analyze outcomes associated with obesity in a large cohort of hospitalized COVID-19 patients.MethodsWe performed a retrospective study at a tertiary care health system of adult patients with COVID-19 who were admitted between March 1 and April 30, 2020. Patients were stratified by body mass index (BMI) into obese (BMI ≥ 30 kg/m 2) and non-obese (BMI < 30 kg/m 2) cohorts. Primary outcomes were mortality, intensive care unit (ICU) admission, intubation, and 30-day readmission.ResultsA total of 1983 patients were included of whom 1031 (51.9%) had obesity and 952 (48.9%) did not have obesity. Patients with obesity were younger (P < 0.001), more likely to be female (P < 0.001) and African American (P < 0.001) compared to patients without obesity. Multivariable logistic models adjusting for differences in age, sex, race, medical comorbidities, and treatment modalities revealed no difference in 60-day mortality and 30-day readmission between obese and non-obese groups. In these models, patients with obesity had increased odds of ICU admission (adjusted OR, 1.37; 95% CI, 1.07?1.76; P = 0.012) and intubation (adjusted OR, 1.37; 95% CI, 1.04?1.80; P = 0.026).ConclusionsObesity in patients with COVID-19 is independently associated with increased risk for ICU admission and intubation. Recognizing that obesity impacts morbidity in this manner is crucial for appropriate management of COVID-19 patients. 相似文献