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排序方式: 共有577条查询结果,搜索用时 218 毫秒
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OBJECTIVES: The cells of the junctional epithelium (JE) provide and maintain the epithelial attachment, and remain morphologically and phenotypically distinct from oral sulcular (OSE) and external oral epithelia (EOE), from which they may be regenerated de novo. Expression of cytokeratins (CK) in human epithelia has been shown to be highly site-specific, implying a functional role. The aims of this study were to differentiate between the cyto-keratin profiles of JE, OSE, EOE and pocket epithelia (PE) in health and disease, in smokers and non-smokers.
MATERIALS AND METHODS: The cytokeratin profiles of 40 samples of healthy and clinically inflamed human gingival tissue taken from 15 smokers and 25 non-smokers were studied by immunocytochemistry. Cryostat sections of fresh frozen gingival tissues were stained with a panel of monoclonal antibodies (mAb) and visualised by a biotin-Streptavidin-peroxidase complex technique.
RESULTS: JE and PE expressed an identical range of cytokeratins irrespective of the inflammatory or smoking status, with the exception of CK4 expression, which tended to be increased in smokers. The OSE and EOE expressed non-cornifying and cornifying differentiation cytokeratins respectively, but in the presence of inflammation, both these epithelia showed increased expression of CK19 at a basal level in association with expression of one or more of the simple cytokeratins. JE/PE expressed CK17 in external layers only, approximating the tooth surface. All epithelia expressed CK6,16 the markers of high cell turnover.
CONCLUSIONS: CK19 was a consistent differentiation marker for JE and PE.Expression of CK8,18 was enhanced by inflammation. CK4 expression increased in association with smoking. Markers of differentiation were not always co-expressed equally within a pair. Pairs were not always completely mutually exclusive with frequent co-localisation. 相似文献
MATERIALS AND METHODS: The cytokeratin profiles of 40 samples of healthy and clinically inflamed human gingival tissue taken from 15 smokers and 25 non-smokers were studied by immunocytochemistry. Cryostat sections of fresh frozen gingival tissues were stained with a panel of monoclonal antibodies (mAb) and visualised by a biotin-Streptavidin-peroxidase complex technique.
RESULTS: JE and PE expressed an identical range of cytokeratins irrespective of the inflammatory or smoking status, with the exception of CK4 expression, which tended to be increased in smokers. The OSE and EOE expressed non-cornifying and cornifying differentiation cytokeratins respectively, but in the presence of inflammation, both these epithelia showed increased expression of CK19 at a basal level in association with expression of one or more of the simple cytokeratins. JE/PE expressed CK17 in external layers only, approximating the tooth surface. All epithelia expressed CK6,16 the markers of high cell turnover.
CONCLUSIONS: CK19 was a consistent differentiation marker for JE and PE.Expression of CK8,18 was enhanced by inflammation. CK4 expression increased in association with smoking. Markers of differentiation were not always co-expressed equally within a pair. Pairs were not always completely mutually exclusive with frequent co-localisation. 相似文献
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YP Panayiotopoulos MD PhD S Padayachee PhD BSC ACE Colchester PhD FRCP PR Taylor MChir FRCS 《International journal of clinical practice》1997,51(6):375-377
In early series the majority of carotid endarterectomies were performed in patients with amaurosis fugax (AFx) or transient ischaemic attacks (TIAs) who were thought to have atheromatous ulcers of the carotid bifurcation or the internal carotid artery (ICA). The degree of stenosis was considered to be of secondary importance. We compared our own data with two British series undertaken in the early and late 80s/early 90s. This reflects the broadening of indications and the change of practice for carotid endarterectomy over the years, on the one hand towards including patients who are at greater risk of perioperative stroke (previous CVAs vs TIAs, crescendo TIAs and stroke in evolution), and on the other towards patients who have had no symptoms attributable to the carotid lesion (asymptomatic cases, combined carotid and cardiac procedures). 相似文献
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Jacqueline AM Smith DL Patil OT Daniels Y-S Ding J-D Gallezot S Henry KHS Kim S Kshirsagar WJ Martin GP Obedencio E Stangeland PR Tsuruda W Williams RE Carson ST Patil 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(2)
Background:
Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.Methods:
We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.Results:
TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.Conclusions:
These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation. 相似文献7.
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Oral sumatriptan in the acute treatment of migraine and migraine recurrence in general practice 总被引:1,自引:0,他引:1
Scott RJ; Aitchison WR; Barker PR; McLaren GI 《QJM : monthly journal of the Association of Physicians》1996,89(8):613-622
We investigated the efficacy, safety and tolerability compared with placebo
of a second dose of oral sumatriptan 100 mg in 1349 general practice
patients who had already treated a moderate or severe migraine headache
with 100 mg sumatriptan 4 h earlier. Headache was relieved by the first
sumatriptan dose in about 70% of patients, but the second dose did not
produce significantly more relief than placebo, either in nonresponders or
in the group as a whole, nor did it reduce other symptoms (photophobia,
nausea, vomiting, etc,) at 8 h, or influence the incidence of headache
recurrence. The drug was well-tolerated, and a further single dose was
effective in treating recurrence after initial relief. A single 100 mg dose
of sumatriptan is an effective acute treatment for migraine. A second dose
should be reserved for treating headache recurrence.
相似文献
10.
目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。
方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。
结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。
结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。 相似文献