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131.
运用二元碱氮置换吸附红外光谱法、分子筛孔径分布测定技术、XPS技术,考察了丝光沸石表面酸性与孔结构的相互关系、钯在丝光沸石上分布情况和价态及其与沸石的相互作用。结果表明,随着丝光沸石脱铝程度的增加,表面出现大量不规整晶格,存在较多的次级孔道。强质子酸中心主要分布在它的“外表面”。钯在其表面富集,并与“外表面”上的质子酸中心协同作用,促进了轻质烷烃异构化反应。  相似文献   
132.
杨清林  黄贞明 《中成药》1995,17(10):13-14
采用薄层扫描法对复脉定冲剂中远志有效成分3,4,5-三甲氧基反式肉桂酸乙酯的含量进行测定。方法简单、快速,结果可靠,可作为该制剂的质控标准。  相似文献   
133.
Propionic acidemia is a rare hereditary disease which is an autosomal recessive disorder. Defect of propionyl CoA carboxylase results in abnormal accumulation of propionate and its metabolites which interfere the pathway of glycine cleavage and the urea cycle. This organic acidemia is characterized by a wide spectrum of clinical and biochemical findings, including recurrent vomiting, difficult feeding, lethargy, hypotonia, metabolic ketoacidosis, hyperglycinemia and hyperammonemia during the acute episodes. We present a male newborn infant who sustained this disorder and was managed successfully with blood exchange transfusion, peritoneal dialysis, supplemented with sodium benzoate and sodium bicarbonate therapy. Urine gas chromatography disclosed significant elevation of propionate and its metabolites which subsided 2 days after peritoneal dialysis. Special designed formula was then given with restriction of protein intake and supplement with sodium benzoate and sodium carbonate. Prenatal genetic counseling is necessary in further pregnancy. Diagnosis can be obtained when propionyl CoA carboxylase activity is low in cultured amniotic fluid cells or chorion villi sample or when there is abnormally high methylcitrate level in amniotic fluid.  相似文献   
134.
微量元素锌在佝偻病治疗中的效果观察   总被引:7,自引:1,他引:6  
宋红潮  黄婉萍  梁友芳 《广西医学》2003,25(11):2120-2122
目的 :探讨补充锌 +维生素D +钙剂治疗佝偻病的效果。方法 :随机分为 3组 ,每组各 5 3例。对照组给予常规治疗 (即维生素D +钙剂 ) ,治疗 1组先给予锌治疗 1个月后 +常规治疗 ,治疗 2组同时给予锌 +常规治疗。 3个月为 1疗程。治疗前后检测血清微量元素及骨碱性磷酸酶 (BALP)等项目。结果 :治疗 1、2组疗效好于对照组 ,差异非常显著 (P <0 0 1) ;治疗1组疗效好于治疗 2组 ,差异有显著性 (P <0 0 5 )。结论 :治疗大多数伴低锌的佝偻病先补锌 1个月 ,再加常规治疗 ,疗效更佳。  相似文献   
135.
重组人表皮生长因子对促进Ⅱ度烧伤愈合的作用   总被引:5,自引:0,他引:5  
目的 探讨重组人表皮生长因子(rhEGF)对促进Ⅱ度烧伤创面愈合的作用。方法 采用自身对照研究方法,选取46例Ⅱ度烧伤患者观察最适治疗浓度创面局部应用的治疗效果及不良反应。结果 在浅Ⅱ度烧伤创面,观察组的愈合时间为(8.7±2.1)天,对照组为(12.2±2.4)天,而深Ⅱ度烧伤创面观察组的愈合时间是(13.4±2.6)天,对照组为(19.2±3.2)天。与对照组相比,观察组创面愈合时间均有明显缩短(P<0.01),结论 rhEGF对Ⅱ度烧伤创面均可有效地促进组织修复,加快创面愈合速度,有良好的促进愈合作用,而药物反应极轻微。  相似文献   
136.
羽化1~2天的中华按蚊.致倦库蚊和白纹伊蚊分别胸内接种马来丝虫微丝蚴,在接种后的第3、4、5和9天,分头、胸、腹3部解剖计算各种蚊虫体内黑化微丝蚴及发育各期幼虫。结果表明:中华按蚊、致倦库蚊和白纹伊蚊的微丝蚴黑化率分别为51·6%、86·1%和69·5%,差异显著;3种蚊虫体内的感染期幼虫率及感染期幼虫阳性率分别为35.3%、1·6%、0%和83·9%、23·5%、0%。黑化微丝蚴较多地集中在蚊虫腹部,占黑化微丝蚴总数61·6%~78·4%。  相似文献   
137.
A 51-year-old man was admitted because of hemoptysis. Physical examinations and chest XP revealed no abnormal findings. Fiberoptic bronchoscopy showed pulsatile bleeding at the orifice of right B6. Right bronchial arteriography showed a markedly dilated and tortous bronchial artery and shunting to the pulmonary arterial system in the middle and lower lobes. Pulmonary arteriography showed complete obstruction of the right middle lobar and lower lobe segmental arteries (A6, 9, 10). The hemoptysis was thought to be due to increased blood flow of the right bronchial artery, which compensated for reduced right pulmonary arterial flow. Right middle and lower lobe resection was done to prevent further hemoptysis. The resected specimen revealed old thromboemboli in the right middle and lower lobe pulmonary arteries. In this case old pulmonary embolism should be considered as a cause of intrabronchial bleeding.  相似文献   
138.
The authors compared the inhaled methacholine and exercise responses in 22 stable unmedicated asthmatic patients. The exercise and methacholine challenges were performed at one to three week intervals. Bronchial responsiveness to methacholine was measured in relation to the concentration of methacholine (PC20M). The response to exercise was expressed as the percentage of fall in FEV1, from the pre-exercise FEV1 The findings showed that 21 of 22 subjects demonstrated a fall in FEV1, of more than 20% after methacholine challenge, while only 9/22 subjects experienced a similar decrease in FEV1. All 9 of these positive response exercise cases completed three consecutive exercise challenges prior to the methacholine challenge. Of these cases, five were refractory to the repeated exercise challenge, and the PD20M at the nonexercise stage was significantly lower than the postexercise state. In fact, the methacholine challenge sensitivity actually decreased (PD20 increased) after repeated exercise. The authors concluded that methacholine seems to be a more sensitive bronchial provocation test than exercise. Second, only 55.6% of the exercise test-positive subjects were refractory to the second exercise challenge. Therefore, other factors besides the release of mediators should be considered in exercise induced asthma. Third, methacholine sensitivity actually decreased (PD20 increases) after repeat exercise challenge.  相似文献   
139.
31P, 1H and lactate spectroscopic imaging was used to evaluate the effects of hypothermia on focal cerebral ischemia produced by middle cerebral artery occlusion. The effects on high energy phosphate metabolism, pH, lactate and NAA were investigated in 24 spontaneously hypertensive rats subjected to either permanent or transient ischemia. Under either normothermic (37.5°C) or hypothermic (32°C) conditions, with permanent 6-h occlusion, there was little difference between groups in either the NMR measurements or the volume of infarction. In animals that underwent 3 h of ischemia followed by 12 h of reperfusion, the ischemic changes in lactate, pH, NAA, and high-energy phosphate returned toward control values, and there was a protective effect of hypothermia (infarct volume of 211 ± 26 and 40 ± 14 mm3 in normothermic and hypothermic groups, respectively). Thus, hypothermia did not ameliorate the changes in lactate, pH, NAA, or high energy phosphate levels occurring during ischemia, however, during reperfusion there was an improvement in both the recovery of these metabolites and pathological outcome in hypothermic compared with normothermic animals.  相似文献   
140.
用PCR技术对12例神经肌肉性疾病患者的16个标本进行了线粒体DNA缺失情况的研究。发现2例帕金森氏病患者的肌肉组织以及其中1例的外周血和另1例肌营养不良(Erb型)患者的肌肉组织中线粒体DNA至少有526bp的缺失。还对线粒体DNA的部分缺失与疾病发生的关系进行了讨论。  相似文献   
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