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71.
Chemokines are involved in the control of dendritic cell (DC) trafficking, which is critical for the immune response, namely in allergic contact dermatitis (ACD). In this work, we investigated by flow cytometry the effect of the contact sensitizers 2,4-dinitrofluorobenzene (DNFB), 1,4-phenylenediamine (PPD) and nickel sulfate (NiSO4), on the surface expression of the chemokine receptors CCR6 and CXCR4 in DC. As an experimental model of a DC we used a fetal skin-derived dendritic cell line (FSDC), which has morphological, phenotypical and functional characteristics of skin DC. Our results show that all the skin sensitizers studied decreased the membrane expression of the chemokine receptors CCR6 and CXCR4. In contrast, 2,4-dichloronitrobenzene (DCNB), the inactive analogue of DNFB without contact sensitizing properties, was without effect on the surface expression of these receptors. Lipopolysaccharide (LPS), which induces the maturation of DC, also reduced surface CCR6 and CXCR4 expression.  相似文献   
72.
Purpose : To report eight patients with diagnosed systemic lupus erythematosus (SLE) who presented with a variety of neuro‐ophthalmological complications and outcomes. Methods : A review of the follow up, subsequent management and outcomes of the neuro‐ophthalmological complications of eight patients with SLE. Results : The patients presented with a myriad of symptoms of varying severities. The most common manifestations were that of optic neuropathy and eye movement abnormalities. The outcome was variable ranging from complete recovery to optic atrophy with navigational visual acuity. Treatment was often empirical, although early treatment with corticosteroids has been tried with varying success. Conclusions : The pathophysiology in the neuro‐ ophthalmological manifestations of SLE is thought be due to vaso‐occlusive disease of the small vessels of the nerve and brain, secondary to an autoimmune process. Ophthalmologists may need to consider the diagnosis of SLE in young women who present with a recent onset of neuro‐ophthalmological symptoms and signs.  相似文献   
73.
Aim : To determine what New Zealand ophthalmologists, general practitioners and optometrists consider important ophthalmic topic areas requiring emphasis in the medical undergraduate curriculum. Method : A total of 793 questionnaires related to the content and teaching of undergraduate ophthalmology were sent to ophthalmologists, general practitioners and optometrists. Results were analysed separately for the three respondent groups and as a whole. Results : Four hundred and fourteen questionnaires were returned (52% return rate). Overall responses of the three participant groups were similar and agreed favourably with the current curriculum. The ability to measure visual acuity (97%) and pupillary reflexes (93%), perform ophthalmoscopy (92%), and assess visual fields (68%) were regarded as ‘important or essential’ by the majority of respondents. Only 53% of respondents consider the ability to diagnose chronic open angle glaucoma as important. The respondents stressed the importance of the diagnosis of predominantly anterior segment disease contrasting with the traditional bias towards the teaching of ophthalmoscopy and posterior segment disease. The majority of respondents stressed the importance of graduating medical students being able to treat bacterial and allergic conjunctivitis, styes, blepharitis, corneal abrasion, and corneal and conjunctival foreign bodies, areas present but not normally emphasized in current curricula. Conclusion : The findings of this study provided additional data to facilitate curriculum design and illustrated the value of an integrated problem‐based learning approach in ophthalmology undergraduate teaching.  相似文献   
74.
目的:观察急性髓性白血病经混合造血干细胞移植后,应用供者淋巴细胞输注 白细胞介素2治疗的效果,并与移植后未经特殊治疗的效果进行比较。方法:①选取2000-01/2004-07解放军兰州军区兰州总医院全军血液病中心收治的19例急性髓性白血病患者,实验经医院伦理委员会批准,患者均知情同意。随机数字表法分为两组:观察组8例,年龄17~40岁,M2a 4例,M4 1例,M5a 3例;对照组11例,年龄19~39岁,M2a 2例,M3a 2例,M4 3例,M5a 4例。②两组患者采用化疗联合重组人粒细胞集落刺激因子的方法动员自体外周血造血干细胞,采集后液氮中保存5d备用。③术前采用直线加速器对患者全身及肺部照射,预处理完毕后实施混合造血干细胞移植。首先回输自体单个核细胞中位数为4×108/kg,CD34 细胞中位数为6.2×106/kg,粒-巨噬祖细胞集落形成单位中位数为5.8×104/kg。间隔1~6h后,采集人类白细胞抗原半相合异体骨髓,按回输自体单个核细胞数的1/6~1/10输注给患者。④两组患者移植期间均住无菌层流病房,给予相应并发症的防治及支持治疗。在粒细胞降至0时注射重组人粒细胞集落刺激因子150μg/12h,促进造血恢复。观察组给予供者淋巴细胞输注 白细胞介素2治疗,每次采集的供者淋巴细胞中,CD3 淋巴细胞中位数为1.43×108/kg,CD4 细胞中位数为0.97×108/kg,CD8 细胞中位数为0.41×108/kg,中位治疗次数4(1~7)次,回输后即开始应用100wu/d重组人白细胞介素2,共10d。对照组混合造血干细胞移植后未给予特殊治疗。结果:19例急性髓性白血病患者均进入结果分析。①造血恢复:两组患者均获得造血重建,术后4~9d粒细胞均降至0,12~17d粒细胞达0.5×109L-1,16~21d白细胞达4.0×108 L-1,19~23 d血小板达20×108 L-1。16~21 d骨髓检查示恢复期骨髓象。②术后并发症:两组患者不同程度地出现口腔溃疡,随着造血恢复,7~10d溃疡消失。观察组1例患者出现出血性膀胱炎,两组各2例患者出现发热。无肝静脉闭塞病和移植物抗宿主病发生。③嵌合体形成:观察组中1例M4患者形成嵌合体,对照组中2例M4患者与1例M5患者形成嵌合体,嵌合体持续存在3~12个月。④供者淋巴细胞输注 白细胞介素2疗效:观察组中有1例M2a患者在接受2次特殊治疗后7个月复发死亡;1例M2a患者接受2次特殊治疗后1年出现骨髓增生异常综合征,脑出血死亡,1例M5a患者应用特殊治疗1次后出现不明原因高热、抽搐,死于癫痫持续状态,其余5例患者随访2年均健康存活,长期生存率为62.5%(5/8)。对照组有2例M2a患者、2例M4患者、1例M5患者于移植后1~7个月复发死亡,1例M3患者于移植后25d死于脑出血,其余2例M3患者、2例M4患者、1例M5患者随访2年均健康存活,长期生存率为45.4%(5/11)。结论:混合造血干细胞移植后应用供者淋巴细胞输注 白细胞介素2治疗,急性髓性白血病患者均获得造血重建且无移植物抗宿主病发生,其长期生存率有效提高。  相似文献   
75.
Aims/IntroductionTo examine the association between cholesterol efflux capacity (CEC) of serum high‐density lipoprotein (HDL) and cognitive function and brain structures in older people with diabetes mellitus.Materials and MethodsParticipants of a randomized placebo‐controlled trial of 27‐month vitamin B12 supplementation in older people with diabetes mellitus, which showed no effect on cognition, were further followed up at month 72. Cognitive tests included the Clinical Dementia Rating scale, Neuropsychological Test Battery in memory, executive function and psychomotor speed. Brain magnetic resonance imaging scans were carried out in a subset at baseline, month 27 and month 45. Fasting serum at baseline, month 9, month 27 and month 72 were analyzed for adenosine triphosphate‐binding cassette transporter A1‐mediated CEC of HDL and apolipoprotein A1 (ApoA1).ResultsSerum HDL cholesterol at baseline was associated with better executive and memory function at follow up. Serum ApoA1 was associated with a better memory Z‐score at month 18. Serum CEC and ApoA1 were not associated with Clinical Dementia Rating scale, Neuropsychological Test Battery, hippocampal volume and white matter disease on magnetic resonance imaging at baseline and whole brain atrophy rates. They were also not associated with cognitive function at month 27 and 72 on multilevel modeling. CEC and ApoA1 decreased significantly from baseline to month 27. Faster decliners in CEC had a greater increase in brain peak width of skeletonized mean diffusivity.ConclusionsHigher serum HDL cholesterol was associated with more favorable changes in memory and executive function in older people with diabetes mellitus. However, this was not due to CEC or ApoA1. A decline in CEC was associated with small vessel disease in the brain.  相似文献   
76.
77.
应用新型单克隆抗体T_8/S_6F_1和流体细胞测定仪双色荧光程序检测了15例Graves病和8例Hashimoto甲状腺炎患者循环和甲状腺内的细胞毒性T细胞(cytotoxic T ceils,Tc)的分布。传统的单克隆抗体CD_8(OKT_8或Leu_2)仅能检测含有两个次亚群——抑制性T细胞(Ts)和细胞毒性T细胞(Tc)的Ts/TcT细胞亚群,不能将它们区别开来。本文应用的单克隆抗体T_8/S-6F_1首次能够单独测定Tc亚群。Graves病和Hashimoto甲状腺炎患者的循环Tc亚群分别为27.6±11.2%和27.5%±12.2%,与正常对照组差异无显著性。两组患者甲状腺内的Tc亚群数目也未见增加。Graves病患者甲状腺内Te细胞为16.45±4.7%。本文结果提示:AITD患者循环内和甲状腺内的细胞毒性T细胞亚群的数目未见增加。  相似文献   
78.
79.
Magnetic resonance imaging of prosthetic heart valves   总被引:1,自引:0,他引:1  
Soulen  RL; Budinger  TF; Higgins  CB 《Radiology》1985,154(3):705-707
To evaluate the safety of magnetic resonance (MR) imaging of prosthetic heart valves, nine different synthetic and tissue valves were studied ex vivo. Deflection was measured in 0.35-tesla (T) and 1.5-T superconducting magnets and at the edge of the bore of a 2.35-T electromagnet in field gradients of 5, 1.1, and 6.3 mT/cm, respectively. No valve deflected in the 0.35-T magnet; six synthetic valves deflected 0.25 degrees-3 degrees in the 1.5-T magnet; all valves deflected 1 degree-27 degrees at the edge of the 2.35-T magnet. Each valve was then submerged in a vial of water and the temperature was measured immediately before and after each of two spin-echo imaging sequences in the two superconducting magnets. No significant temperature rise followed exposure in either magnet. Image distortion varied from negligible to severe in both imagers; magnitude of distortion paralleled magnitude of deflection. These data suggest that patients with present-day prosthetic heart valves can be safely imaged in present-day MR imagers and that prosthesis-induced artifacts will not interfere with interpretation in most instances.  相似文献   
80.
A computerized method that requires only 1-2 minutes to quantify gallbladder volume from real-time sonograms is described. This time is considerably shorter than that required using the hand-calculation method. There was a highly significant correlation between gallbladder volumes calculated by computer and hand (r = 0.97; P less than .001).  相似文献   
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