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51.
北京、广州、上海城市居民营养知识、态度、行为的调查   总被引:27,自引:1,他引:26  
谢斌  吴其乐 《卫生研究》1997,26(5):343-348
对北京、广州和上海三大城市随机抽取的965名年龄在20~50岁的城市居民进行有关营养知识、态度和行为(K-A-P)的调查。结果显示,三地区调查对象的营养知识水平不高。营养知识的得分与其自身受教育程度有相关性(r=0.3011,P<0.01)。年龄在35岁以上的对象,营养知识的得分高于年轻人;三地区调查对象对营养知识的获取,合理的膳食模式,卫生的饮食习惯均持有积极、肯定的态度。食物消费频度调查结果表明,米/面、肉/禽、蔬菜、水果、奶及奶制品的消费量较高。此外,89.5%,78.8%和47.8%的调查对象分别选择报纸、电视、广播作为其主要营养信息来源。本次调查为将来的营养宣教的内容和方法提供依据。  相似文献   
52.
目的 探讨感觉神经肽P物质(SP)对离体培养的肉芽组织成纤维细胞表皮生长因子(EGF)表达的调控作用及特点。方法 采用甲醛注射的方法造成Wistar大鼠局部无菌性炎性反应,提取肉芽组织进行成纤维细胞原代培养;采用逆转录—聚合酶链反应(RT—PCR)方法检测SP对肉芽组织成纤维细胞EGF基因表达的调控作用,观察时间及剂量—效应关系;采用Western-blotting方法检测EGF蛋白表达情况,观察时间及剂量—效应关系。结果 10^-7mol/L SP可诱导成纤维细胞EGF mRNA的表达,在作用后6h与对照组比,差异有显著性(P<0.01);SP在10^-8-10^-6mol/L范围内可以显著促进成纤维细胞EGF mRNA表达,在10^-7mol/L达到峰值,10^-5mol/L时与对照组差异无显著性(P>0.05)。10^-7mol/L SP作用12h后可检测到EGF蛋白明显表达增强(P<0.01),24h达高峰,48h后逐渐有所回落。SP在在10^-8--10^-5mol/L范围可诱导EGF蛋白的表达,均在10^-7mol/L剂量点达到峰值(P<0.01)。结论 SP可诱导肉芽组织成纤维细胞EGF基因和蛋白的表达,且呈现出一定的时间和剂量特点,在SP调控创伤愈合的作用中具有重要意义。  相似文献   
53.
VEGF和p53在胰腺癌中的表达及意义   总被引:1,自引:0,他引:1  
目的 探讨胰腺癌组织中血管内皮生长因子 (VEGF)及p5 3蛋白的表达及其临床病理意义。方法 采用SP免疫组织化学方法 ,对 46例胰腺癌组织中VEGF及 p5 3蛋白的表达进行检测。结果 VEGF与 p5 3表达率分别为 65 .2 %和 5 8.7%。p5 3表达与VEGF表达呈明显正相关(P <0 .0 5 )。VEGF表达与胰腺癌淋巴结转移 (P <0 .0 5 )和远处转移 (P <0 .0 1)显著相关 ,而与肿瘤大小 ,病理学分级无关 ,p5 3表达与胰腺癌远处转移 (P <0 .0 5 )显著相关 ,而与肿瘤大小 ,病理学分级及淋巴结转移无关。结论 在胰腺癌中 ,VEGF表达与 p5 3蛋白的表达呈正相关 ,在胰腺癌的转移中起重要作用  相似文献   
54.
目的 :研究启东区肝癌中 P53基因第七外显子转录水平的表达及其与患者临床病理特征间的关系。方法 :通过 RT- PCR确定 P53基因第七外显子在 47对肝癌标本中的表达 ,并分析其与肝癌患者临床病理特征间的关系。结果 :P53基因第七外显子在肝癌及其癌旁组织中均显示差异表达 ,其中 1 7例为上调表达 ,30例为下调表达 ,上下调表达之间差异显著 ;女性、年龄≥ 45岁、AFP( + )、HBs Ag( + )、癌栓 ( + )、肝硬化、病理 Edmondson's 级的病例中 P53基因第七外显子均呈显著下调表达 ;Edmondson's I级病例肝癌组织中 P53基因的 EI显著高于 Edmondson's 级病例。结论 :启东肝癌中 P53基因第七外显子转录水平上存在表达差异 ,且其异常表达与肝癌的临床病理特征有关  相似文献   
55.
幕上星形细胞肿瘤MRI表现与VEGF、P16、Ki-67相关性研究   总被引:1,自引:0,他引:1  
探讨星形细胞肿瘤MRI表现与P16、Ki—67、血管内皮生长因子(vascular endothelial growth factor,VEGF)表达的相关性。材料和方法:收集我院术前经MRI诊断并经手术病理证实的幕上星形细胞肿瘤53例,行常规平扫描后静脉注射Gd—DTPA增强成像;同时采用HE染色及链菌素生物素—过氧化酶连接法进行VEGF、Ki—67、P16的免疫组织化学染色,测定它们的表达指数。结果:星形细胞肿瘤的信号不均匀性、坏死、水肿、占位效应、强化程度与VEGF、Ki—67、P16的表达相关,且随着星形细胞肿瘤恶性程度的增高VEGF、Ki—67的表达增加;P16的表达率降低。结论:星形细胞肿瘤的MRI表现与VEGF、Ki—67、P16的表达密切相关,MRI可以间接判断星形细胞肿瘤的某些生物学行为。  相似文献   
56.
目的 研究利培酮临床效应的个体差异与其代谢酶细胞色素P4 5 0 2D6 (cytochromeP4 5 02D6 ,CYP2D6 )酶基因多态性的相关性。方法 对 88例符合CCMD 3精神分裂症诊断标准的患者和 96例健康对照者作病例 -对照分析。精神分裂症患者给予利培酮治疗 8周 ,用阳性和阴性症状量表 (posi tiveandnegativesymptomscale ,PANSS)评分评价利培酮疗效。采用聚合酶链反应扩增及限制性片段长度多态性 (PCR RFLP)技术对CYP2D6exonⅠ的C188T位点突变进行检测 ,分析利培酮临床效应与其主要代谢酶CYP2D6 /C188T酶基因多态性的相关性。结果 中国上海地区人群的CYP2D6 /C188T突变率(弱代谢型 )为 36 .3% ,病例组和正常对照组间基因型频率总体分布比较无显著差异 (χ2 =1.15 ,df=2 ,P >0 .0 5 ) ,两组间的等位基因频率之间比较也无显著性差异 (χ2 =0 .78,df=1,P >0 .0 5 )。进行性别及有否家族史分组后分析 ,亦无差异存在 ,且CYP2D6 /C188T突变与利培酮临床效应之间并无相关性 (χ2 =1.12 ,df=2 ;χ2 =0 .0 3,df=1,P >0 .0 5 )。结论 未发现中国人CYP2D6 /C188T多态性与利培酮临床效应的个体差异有相关性。  相似文献   
57.
The excitatory responses of neurones in the anterior cingulate cortex of the rat to iontophoretically applied substance P (SP) are reduced by noradrenaline (NA) applied iontophoretically or released from noradrenergic pathways. In order to determine the receptor involved in this inhibitory effect we have studied the effects of a number of receptor-specific adrenergic agonists and antagonists on responses of cingulate neurones to SP in rats anaesthetized with chloral hydrate. Low iontophoretic currents (0-15 nA) of NA, adrenaline and the beta-agonist, clenbuterol, all strongly reduced responses to SP. Isoprenaline was also effective but less consistently so, although problems were experienced with its iontophoretic release from micropipettes. The alpha 1-agonists, phenylephrine and methoxamine were also able to reduce responses to SP. However, this reduction required higher iontophoretic currents (15-60 nA) and was associated with depressant effects on baseline firing rate. The alpha 2-agonist clonidine was only weakly active at high currents and this too was associated with depression of baseline firing. Similar weak effects were noted with dopamine. The inhibitory effects of NA on SP responses were convincingly blocked or reversed by the beta-antagonist, practolol, but not by the alpha 1-antagonist, prazosin. The reduction of SP responses by phenylephrine was also blocked by practolol but unaffected by prazosin. Finally, reduction of SP excitations by activation of the coeruleocortical pathway was also blocked by practolol applied iontophoretically to the cortical cells. These results are consistent with the hypothesis that the effect of NA on SP responsiveness in the cingulate cortex is mediated by beta-adrenoreceptors.  相似文献   
58.
Substance P and human nasal mucociliary activity   总被引:2,自引:0,他引:2  
Summary Substance P (SP), a potent inflammatory agent, has been found in sensory nerve fibres in the nasal mucosa in several experimental animals as well as in man. It may participate in the inflammatory response as part of the mucosal defence against foreign materials. In experimental animals SP has been found to increase mucociliary in airway mucosa. The present study was performed in order to find out the relationship between topically applied SP and nasal mucociliary function in humans. Thirteen healthy volunteers were challenged with 65 µg SP or placebo in a randomized cross over fashion and mucociliary transport time was determined each time using the saccharine dye test. The dose of SP was chosen after an open dose-response study. No statistically significant change in the mucociliary transport time was found after challenge with SP as compared to placebo. The possible reasons for this are discussed.  相似文献   
59.
In a study to elucidate molecular mechanisms in pain, substance P-like immunoreactivity (SP-LI) was measured in lumbar CSF from 75 patients with lower back pain. Two samples – one before and one after lidocaine treatment – were obtained from each patient, and total SP-LI was measured in unfractionated (no HPLC) samples. SP-LI data were separated into three categories: placebo responders, pharmacological responders, and pharmacological non-responders. A significant difference was observed between the total SP-LI measurement of first and second samples of pharmacological non-responders. Distribution of SP-LI immunoreactive molecular species in two CSF patient samples (no ODS) was analyzed with a combination of reversed phase (RP) HPLC and RIA. Immunoreactivity in collected HPLC fractions was measured at calibrated retention times of synthetic SP-sulfoxide (SP-O), SP, and SP5–11. Qualitative and quantitative differences in those HPLC-RIA metabolic profiles were observed within and between those two patients' samples. These data indicate that the type and amount of SP metabolism and SP precursor-processing differs in CSF between these two representative patients and within the short amount of time elapsed between acquiring these two samples.  相似文献   
60.
This study examined the axonal transport of substance P-like immunoreactivity (SPLI) and its content in dorsal root ganglion, trigeminal ganglion, stomach and ileum of non-diabetic rats and two groups of rats with streptozotocin-induced diabetes of 9 months duration. One diabetic group received the aldose reductase inhibitor ‘Statil’ throughout the period of study. To reduce morbidity all diabetic animals were given twice-weekly injections of a long-acting insulin which restricted weight loss but did not prevent regular and severe hyperglycaemia. Axonal transport of SPLI was studied by measurement of accumulation at 12 h ligatures on the left sciatic nerve. There were no differences between the 3 groups either in the calculated anterograde and retrograde mean rates of accumulation (ranges 6.0 to 7.6 and 0.38 to 0.72 mm/h respectively) or mobile fractions of SPLI (means from 0.54 to 0.58). There were, however, marked reductions in anterograde and retrograde accumulations of SPLI in the constricted nerves of the ‘untreated’ diabetics (respectively 57 and 33% of controls;P < 0.01 for both). In the ‘Statil’-treated rats these deficits were attenuated (80 and 75% of controls). Diabetes also reduced the SPLI content of unligated sciatic nerve and trigeminal ganglion (65 and 75% of controls). ‘Statil’ prevented the deficit in the ganglion, but not in the nerve. ‘Statil’ treatment prevented themyo-inositol depletion and attenuated the sorbitol and fructose accumulation seen in the sciatic nerves of the untreated diabetic animals suggesting effective inhibition of aldose reductase in this tissue. The total SPLI content of the stomach and 1-cm segments of ileum were unaltered in the diabetic animals but due to the increased weights of these tissues the SPLI content per unit weight was reduced. These changes were unaffected by ‘Statil’.  相似文献   
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