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41.
为进一步研究呼吸道疾病时的粘液纤毛清除功能,采用99mTc-DTPA气溶胶吸入显像,通过电影显示定性和定量指标分析.对18 例健康受试者和患者进行了显像研究,得到气道清除率和粘液纤毛清除率的正常值,并观察了32例慢性阻塞性肺病(COPD)患者气管-支气管纤毛清除功能的改变.结果显示,健康受试者与COPD患者粘液纤毛清除率(mm/min)分别为3.89±0.92和1.32±0.59,两者比较有显著性差异(P<0.01),COPD患者不同时间气道清除率和粘液纤毛清除率均明显低于健康受试者(P<0.01).本研究方法简便客观,具有定性观察和定量分析的优点,对于呼吸系统其它疾病(如支气管扩张、原发性纤毛无运动)的研究及药物疗效的评价具有重要的临床实用价值.  相似文献   
42.
目的 观察电针肾俞、膈俞、百会穴对拟血管性痴呆小鼠学习记忆障碍的影响。方法 复制脑缺血再灌注拟血管性痴呆小鼠模型 ,并电针肾俞、膈俞、百会穴 ,分别于术后 7天、15天、30天 ,与药物喜德镇对照 ,采用水迷宫法 ,记录游全程时间、错误次数。结果 造模导致了小鼠学习与记忆能力下降 ,表现为游全程时间延长 ,错误次数增加 ,且随着观察时间的延长 ,这种改变逐渐加重。电针和喜德镇均可使模型小鼠的游全程时间缩短 ,错误次数减少 ,但电针组于 7天和 30天时 ,成绩显著优于药物组。结论 电针肾俞、膈俞、百会穴对模型小鼠学习与记忆能力下降有改善和提高作用  相似文献   
43.
At the turn of the last century, side by side with the infiltration of religious culture from Western countries, western medicine spread into Yantai. The religious force, headed by American Presbyterian Mission, carried out charitable activities in the process of preaching and laid down the foundation for western medicine rooted in Yantai by establishing schools, education and training followers. They cultivated local physicians by first setting up clinics which had later transformed into hospitals. These are their major measures for building bases for spreading Christianity by foreigners. The Temple Hill Hospital set up by the American physician Oscar F. Hills in Yantai was a successful example of mutual promotion of missionary and medical activities which pushed forward the spreading and development of western medicine in Yantai.  相似文献   
44.
T管造影合并胰管显影的临床意义   总被引:1,自引:0,他引:1  
本文通过对17年间行“T”管造影的1687例患者的系统性回顾分析,发现有276例患者胰管同时显影,其中69例具有胰腺炎病史,达25%,而无胰管显影的1029例患者中有133例具有胰腺炎病史,达12.9%;二者间具有显著性差异。在胰管显影的病例中,发生过胰腺炎的患者其胆胰汇合角度显著高于未发生过胰腺炎患者的胆胰汇合角度(P〈0.001)。作者认为:“T”管造发生胰管同时显影的病例可有与壶腹隔膜功能陷  相似文献   
45.
GABA(A) receptors mediate inhibition of T cell responses   总被引:4,自引:0,他引:4  
We describe the presence of functional GABA(A) receptors on T cells. GABA inhibited anti-CD3 and antigen-specific T cell proliferation in vitro in a dose-dependent manner that was 1) mimicked by the GABA(A) receptor agonist muscimol (but not the GABA(B) receptor agonist baclofen), 2) blocked by GABA(A) receptor antagonists and a GABA(A) receptor Cl- channel blocker (picrotoxin) and 3) enhanced by pentobarbital. These data suggest that GABA(A) receptors mediate this immune inhibition and that these receptors can be modulated in a similar fashion to their neuronal counterparts. Finally, GABA inhibited DTH responses in vivo. Thus, pharmacological modulation of GABA(A) receptors may provide new approaches to modulate T cell responses in inflammation and autoimmune disease.  相似文献   
46.
47.
Analysis of differential effects of Pb2+ on protein kinase C isozymes   总被引:7,自引:0,他引:7  
Protein kinase C has been implicated as a cellular target for Pb2+ toxicity. We have previously proposed that Pb2+ modulates PKC activity by interacting with multiple sites within the enzyme. In order to further characterize the Pb-PKC interactions we compared the effects of Pb2+ on the CA-dependent and -independent protein kinase C isozymes using recombinant human PKC-alpha, PKC-epsilon, and PKC-zeta as well as the catalytic fragment of bovine brain protein kinase C, the PKC-M. The results demonstrate that, whereas at pM concentrations Pb2+ activates PKC-alpha half maximally (KAct approximately 2 pM), it has no effect on PKC-epsilon, PKC-zeta, or PKC-M activities. The activation of PKC-alpha by Pb2+ is additive with Ca2+ in a manner indicating interaction with half of the calcium activation sites. In the micromolar range of concentrations, Pb2+ inhibits all PKCs with estimated K0.5 of 1.0, 2.3, 28, and 93 microM for PKC-M, PKC-alpha, PKC-epsilon, and PKC-zeta, respectively. Examination of Pb2+ effects on PKC-M kinetics indicates a mixed type inhibition with respect to ATP and noncompetitive inhibition with respect to histone. Taken together with the results of our previous study (Tomsig and Suszkiw, J. Neurochem. 64, 2667-2673, 1995) and the evidence for the existence of two Ca2+ coordination sites Ca1 and Ca2 within the C2 domain (Shao et al., Science [Washington, D.C.] 273, 248-251, 1996), the results of the current study provide further support for a multisite Pb-PKC interaction scheme wherein lead (1) partially activates the enzyme through pM-affinity interactions with the Ca1 site and inhibits the divalent cation-dependent activity through nM-affinity interactions with Ca2 site in the C2 domain and (2) inhibits the constitutive kinase activity through microM-affinity interactions with the catalytic domain. The concentration dependence of the differential effects of Pb2+ on the calcium-dependent and -independent PKCs underscores the importance of the C2 motif as a high affinity molecular target for Pb2+.  相似文献   
48.
F Z Tian  J Myles  J M Howard 《Surgery》1992,111(1):109-113
The natural history of classic mucinous cystic neoplasms of the pancreas has been previously defined. In this report, an unusual variant of a pancreatic mucinous cystic neoplasm, termed "mucinous pancreatic duct ectasia of latent malignancy," is described. The lesion is characterized by massive dilatation of the main pancreatic duct and its tributaries. Histologically, the ducts are lined by epithelium, which is indistinguishable from the classic mucinous cystic neoplasms. Until the natural history of classic mucinous cystic neoplasm is better documented, resection appears to be the treatment of choice.  相似文献   
49.
喉癌组织恶性度与颈淋巴结转移关系   总被引:2,自引:0,他引:2  
采用五因素评点法对40例喉鳞癌进行组织学和临床方面的研究。结果表明,组织恶性度与T分期无相关性,浸润方式弥散及恶性度高(评分≥11)的肿瘤发生颈淋巴结转移率显著高于有完整肿瘤边界者及恶性度低(评分≤10)者。提示喉癌组织恶性度在预测颈淋巴结转移上有实用价值,可临导临床治疗方案的选择。  相似文献   
50.
OBJECTIVE: To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN: Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING: A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS: 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES: Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS: Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS: Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished.  相似文献   
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