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21.
S L Marklund H Heiskala T Westermarck P Santavuori 《Clinical science (London, England : 1979)》1986,71(1):57-60
The neuronal ceroid-lipofuscinoses is a group of diseases characterized by a widespread accumulation in the body of pigments believed to be end-products of lipid-peroxidation damaged organelles. It was recently shown that cerebrospinal fluid from patients with infantile and juvenile neuronal ceroid-lipofuscinosis were less protective against superoxide radical-induced hydroxyl radical formation compared with controls. The content of superoxide dismutase isoenzymes in cerebrospinal fluid and in plasma from patients with different forms of neuronal ceroid-lipofuscinosis was analysed. No significant difference from controls could be demonstrated in samples from patients with juvenile neuronal ceroid-lipofuscinosis. The few samples from patients with infantile and late infantile neuronal ceroid-lipofuscinosis analysed all fell within the range defined by the controls. 相似文献
22.
23.
人白细胞介素12在哺乳动物细胞中的稳定表达及其生物活性的研究 总被引:1,自引:0,他引:1
目的采用遗传基因工程方法获得具有生物活性的人白细胞介素12,探索其治疗肿瘤和慢性肝炎的可行性。方法采用已克隆的国人IL-12基因序列,利用内部核糖体切入位点(IRES)完成IL-12P35、P40双亚基共表达载体的构建,通过转染CHODHFR缺陷细胞,双抗夹心ELISA法筛选阳性克隆,MTX加压扩增,PCR检测其基因整合,T淋巴细胞增殖和诱生γ干扰素实验检测其生物活性。结果获得了稳定高效表达人IL-12的工程细胞系,表达产物为70×103左右的糖蛋白。结论本研究得到的基因重组人IL-12具有良好的生物活性,有强的诱导产生γ干扰素的能力和诱导活化T淋巴细胞增殖能力。 相似文献
24.
脐血CD34+细胞体外定向诱导分化为T淋巴细胞的实验研究 总被引:1,自引:0,他引:1
目的:建立利用人造血干/祖细胞体外定向诱导分化为T淋巴细胞的方法,为研究T细胞生物学特性及细胞免疫提供技术平台。方法:MACS方法分离人脐带CD34^ 细胞接种到人胎儿胸腺基质单层细胞上,IMDM液体培养基含20%人AB血清并加入FL、IL-12、IL-7和IL-2细胞因子组合,于培养7、14、21、28、35、42天取非贴壁细胞利用流式细胞仪对细胞表型进行检测,并进行细胞形态学分析。结果:2周后,CD4^ CD8^ 非成熟T淋巴细胞占细胞总数的0.3%-13.3%,4-5周CD4^ CD8^ T淋巴细胞达到高峰占16.6%-26.5%,且CD3^ CD4^ CD8^ 和CD3^ CD4^-CD8^ T淋巴细胞逐渐增多,6周后达26.5%~64.9%和11.6%-38.9%。培养成熟的T淋巴细胞经PHA IL-2刺激后瑞氏染色鉴定可见大原始淋巴细胞存在。结论:利用人脐血CD34^ 在体外人胎儿胸腺基质单层细胞上加FL、IL-12、IL-7和IL-2细胞因子组合条件下,可诱导分化出T淋巴细胞,并且培养的T细胞对有丝分裂素刺激有增殖反应。 相似文献
25.
目的 探讨孤束核联合亚核前部(acNTS)损伤在慢性束缚应激(CRS)所致的胰岛素抵抗性高血糖症发生中的作用。 方法 采用CRS大鼠模型(n=20;7 d束缚+3 d自由活动,共40 d),检测葡萄糖代谢相关指标。 结果 CRS导致约1/3的个体(n=7)持续性的中度胰岛素抵抗性高血糖(空腹血糖不超过11 mmol/L)。CRS高血糖鼠acNTS可观察到神经元染色浓缩,Caspase-3表达和TUNEL阳性染色,提示出现神经元凋亡样改变。机械损伤acNTS(n=6),空腹血糖水平逐渐升高,也能导致胰岛素抵抗性高血糖, 且高胰岛素血症、胰岛平均体积增大和血清皮质酮水平不变等特点与CRS小鼠一致。 结论 CRS损伤了acNTS的葡萄糖敏感神经元,从而使血糖调节紊乱。 相似文献
26.
华南地区质粒介导超广谱β-内酰胺酶的基因分型研究 总被引:59,自引:4,他引:59
目的:了解华南地区质粒介导超广谱β-内酰胺酶(ESBLs)的发生率及基因型特征。方法:收集2001年4月-9月革兰阴性菌临床分离无重复株共1184株,采用NCCLS表型筛选和确认试验进行了ESBLs产酶的识别,E-test法检测各亚型ESBLs的MICs值,质粒接合及电转化实验,耐药质粒提取及酶切指纹分析,等电聚焦电泳,PCR通用引物扩增TEM、SHV、CTX-M、VEB、PER、SFO基因及其克隆测序进行ESBLs基因分型和质粒定位。结果:革兰阴性苗ESBLs的检出率为14.6%(173/1184);获得产ESBLs接合子67株,电转化子11株,其中产CTX-M-14型ESBLs为33.3%(26/78)、CTX-M-3为23.1%(18/78)、CTX-M-9为14.1%(11/78)及SHV-2a为2.6%(2/78),未定型为5.1%(4/78);29.5%(23/78)野生株伴广谱酶TEM-1或SHV-1型;各型ESBLs基因约定位在35-190kb大小的可接合性低执行者拷贝数天然质粒上;CTX-M型ESBLs以对头孢噻肟高水平高耐为特征。结论:华南地区质粒介导的ESBLs以CTX-M型衍生酶为主,其次是SHV型酶。 相似文献
27.
How well do nurse-run telephone consultations and consultations in the surgery agree? Experience in Swedish primary health care.
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B Marklund P Koritz E Bjorkander C Bengtsson 《The British journal of general practice》1991,41(352):462-465
The telephone consultation service is an important part of Swedish primary health care. However, few studies have compared telephone consultations managed by nurses with surgery consultations managed by both doctors and nurses in terms of information obtained from the patient regarding his or her symptoms, and the management decisions made. In this study, the information obtained from a patient during a telephone consultation with a health centre nurse and the management decisions made, were compared with those obtained at a subsequent surgery consultation with the same nurse, and then with a doctor. Of 200 telephone consultations at a health centre (50 in each of the following four categories as defined by the management decision of the nurse: acute case, semi-acute case, referral case and self-care case), 193 patients were included in the study. The information given to the nurse during the telephone consultation was recorded. The patient was then asked to come for a surgery consultation on the same day, first with the same nurse and then with a general practitioner. A comparison was made between the information obtained and the decisions taken in these three situations. In 185 of the 193 cases (96%) the information led to the same management decision by the nurse, in both the telephone consultation and later in the surgery consultation. In all cases the same history was recorded by the nurse during the telephone and surgery consultations as by the general practitioner. This indicates that in most cases little or no information is missed in a telephone consultation with a nurse as compared with a surgery consultation with a nurse or doctor.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
28.
Antioxidant levels were determined in five patients with the Lesch-Nyhan syndrome. The erythrocyte glutathione peroxidase activity was in average 1.8 times higher in Lesch-Nyhan patients than in controls (1.68 +/- 0.36 versus 0.92 +/- 0.17 mu kat/g hemoglobin, p less than 0.001). Plasma CuZn-superoxide dismutase activity was two times higher (p less than 0.001) and Mn-superoxide dismutase activity was 1.5 times higher (p less than 0.05) than in controls, whilst erythrocyte CuZn-superoxide dismutase, plasma extracellular-superoxide dismutase and lymphocyte superoxide dismutase did not differ between Lesch-Nyhan patients and healthy controls. These data might indicate that Lesch-Nyhan patients are exposed to a higher oxidative load than healthy control persons. 相似文献
29.
Edward D. Levin Todd C. Brady Elizabeth Crapo Hochrein Tim D. Oury Lena M. Jonsson Stefan L. Marklund James D. Crapo 《Behavior genetics》1998,28(5):381-390
Extracellular superoxide dismutase (EC-SOD) controls the availability of extracellular superoxide (O
2
-
), which is important for a variety of physiological pathways, including the primary means of inactivating nitric oxide (NO). The role of EC-SOD in neurobehavioral function has been until now unexplored. In the current studies, the phenotypic expression of genotypic alterations of EC-SOD production in mice were characterized for spatial learning and memory. Dramatic impairments in spatial learning in the win-shift 8-arm radial maze were seen in both EC-SOD knockout mice and EC-SOD overexpressing mice. The EC-SOD overexpressing mice were further characterized as having significant deficits in a repeated acquisition task in the radial-arm maze, which permitted the dissociation of long and short-term learning. Long-term learning was significantly impaired by EC-SOD overexpression, whereas short-term learning was not significantly affected by EC-SOD overexpression. NO systems have been shown to be importantly involved in learning and memory. This may be important in the current studies because EC-SOD has primary control over the inactivation of NO. We found that EC-SOD overexpressing mice were resistant to the cognitive effects of L-NAME (NG-nitro-L-arginine methyl ester hydrochloride), an NO synthase inhibitor. Decreased NO catabolism in these mice may have served to counter the effects of NOS inhibition by L-NAME. The current finding that EC-SOD levels that were either higher or lower than controls impaired learning demonstrates that the proper control of brain extracellular (O
2
-
) may be more vital than merely reduction of brain extracelluar (O
2
-
) in maintaining adequate learning function. 相似文献
30.
目的探讨CD40靶向小干扰RNA(即短发夹RNA,shRNA)对大鼠异体肢体移植急性排斥反应及细胞凋亡的影响。方法以纯系SD大鼠为供体,纯系Wistar大鼠为受体,行同种异体右后肢移植。27只大鼠肢体移植后随机分为3组:实验组.注射梭华一Sofast(15μl)-siCD40—2,pSilencer(100μg)载体复合物600μl;空载体对照组,在肢体移植后,即注射Sofast(15μl)-pSilencer4.1-CMVneo(100μg)空载体复合物600μl;生理盐水对照组,在肢体移植注射生理盐水600μl。观察移植物排斥反应征象及存活情况,并于第7天对产生免疫耐受大鼠进行混合淋巴细胞反应(MLR),同时进行组织学检查。结果与其他组相比.实验组移植物发生排斥反应的时间及存活时间均显著延长(P〈0.01)(〉13d),未见排斥反应征象,其他组均于术后近期发生排斥反应;实验组大鼠对供体的淋巴细胞呈现低反应性,移植的供体同系大鼠的肢体得以存活。实验组移植物细胞凋亡率低于其他组。结论在术后不应用免疫抑制剂的情况下,CD40靶向的shRNA干扰可以抗大鼠异体肢体移植急性排斥反应。 相似文献