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991.
OBJECTIVE: To explore a method for quantitative detection of soluble human leukocyte antigen class I(HLA-I) antigens, with the assistance of which we attempt to define the reference value of the antigen in the population of Guangdong Province. METHODS: Sandwich enzyme-linked immunosorbent assay (ELISA) was employed with W6/32 monoclonal antibody serving as the solid phase antibody and beta2 microglobulin antibody as the first antibody. HRP-labeled second antibody and the substrate were added for enzyme-catalyzed coloring. On the basis of the standard curve obtained by sHLA-I standard reagent in serial dilution, the concentration of sHLA-I antigens in the samples of 60 normal subjects from the population of Guangdong province was detected. RESULTS: The sensitivity of this assay was 2.84 ng/ml with variation coefficients of 5.80% within the same batch and 9.00% between batches. The recovery rate ranged from 98.57% to 100.15%. The level of sHLA-I antigens in normal individuals was 699.54+/-360.10 ng/ml. CONCLUSION: Sandwich ELISA is sensitive, specific and stable in the detection of sHLA-I.  相似文献   
992.
We propose a haphazard branching theory to support the concept of bronchopulmonary malinosculations, and we apply this theory to classify congenital bronchopulmonary vascular malformation (BPVM) based on the anatomical results we have found. Between January 1990 and December 1997, a total of 22 pediatric patients (10 male and 12 female), aged 2 days to 14 years (median, 19.6 months), with congenital BPVM were enrolled in this retrospective study. Study modalities include the clinical features and plain chest films (n = 22) plus at least two of the following: echocardiography (n = 13), barium esophagraphy (n = 2), bronchoscopy (n = 4), contrast bronchography (n = 8), high-resolution direct coronal CT (n = 1) and electron beam or ultrafast CT (n = 1) of the chest, MRI (n = 10), MRA (n = 1), contrast cineangiocardiography (n = 9), surgery (n = 11), or autopsy (n = 2). The salient clinical features were recurrent lung infections in 14 patients, acute respiratory distress in 13, associated cardiovascular malformations in 8, dextroversion in 7, congestive heart failure in 7, dextrocardia in 4, and complex congenital heart diseases in 4. There were abnormal openings (malinosculations) of the pulmonary airway in 20 patients: to an artery in 12, to a vein in 8, and to the lung parenchyma in 9. These 22 patients with congenital BPVM can be classified into bronchial malinosculation (10 cases), arterial malinosculation (2 cases), and bronchoarterial malinosculation (10 cases). Congenital BPVM can be classified in terms of bronchopulmonary malinosculation based upon a haphazard branching theory, in which abnormal communications between two independent systems (primitive foregut system and aortic-pulmonary arch system) occurred coincidentally rather than causally.  相似文献   
993.
为研究长期游泳运动老龄小鼠脂质过氧化水平的降低是否与刺激了松果腺释放褪黑素有关,将松果腺切除12月龄昆明种小鼠分为手术组(n=36)、非手术组(n=36)和假手术组(n=12),前2组又各分为对照组、60min组和60min+3%体质量负荷组,对其血清中的MDA浓度进行对比研究.结果:雄性小鼠非手术组中MDA浓度60min组及60min+3%负荷组均显着低于手术同负荷组(P<0.05,P<0.01).雌性小鼠,非手术组60min组MDA浓度显着低于手术组(P<0.05).而在60min+3%负荷组,手术组要显着低于非手术组(P<0.05).提示:长期运动训练降低血清脂质过氧化水平,可能与交感神经兴奋性升高刺激松果腺内褪黑素的合成和释放有关;如果选择负荷不当,会对松果腺机能产生抑制,而对机体抗氧化能力的提高产生负面影响.  相似文献   
994.
PTEN基因蛋白在胆囊癌组织中表达的研究   总被引:4,自引:0,他引:4  
目的 :探讨抑癌基因PTEN蛋白在胆囊癌组织中的表达情况及其临床病理意义。方法 :应用免疫组化对 2 8例胆囊腺癌 ,4例胆囊鳞癌及其相应癌旁组织中PTEN蛋白进行检测 ,并结合患者的临床病理资料进行分析。结果 :PTEN蛋白在 32例癌旁组织中全都呈阳性表达 ,而癌组织中PTEN阳性表达率仅 34.4 %。胆囊癌组织中PTEN蛋白阳性表达与患者性别、年龄及组织类型无明显相关性 ,但与组织分化程度明显相关。结论 :PTEN蛋白在胆囊癌组织中阳性表达率较低 ,说明该基因失活可能在胆囊癌发生发展中起重要作用。PTEN阳性表达对胆囊癌患者的预后有一定意义  相似文献   
995.
青年急性冠脉综合征冠脉造特点及随访   总被引:2,自引:0,他引:2  
目的:探讨青年急性冠状动脉综合征(ACS)冠状动脉(冠状)造影特点及其与远期心脏事件的关系。方法:比较青年ACS与老年ACS患者冠脉病变程度、范围,并进行心脏事件随访。结果:78例青年ACS患者有冠脉病变74例(94.9%),单支病变46例(58.9%);171例老年ACS患者有冠脉病变166例(97.1%),单支病变41例(23.9%)。平均随访9个月,青年ACS患者发生心脏事件者10例(12.8%),其中心绞痛再入院6例(7.7%);老年ACS患者发生心脏事件者47例(27.5%),其中心绞痛再入院30例(17.5%),两组比较差异有显著性(P<0.05)。结论:ACS患者冠状动脉粥样硬化青年时期之前已经发生,ACS预后与冠脉病变程度和年龄呈正相关。  相似文献   
996.
目的阐明针刺捻转补法与泻法的操作是否存在效应上的差异,并探讨其效应差异是否为补泻效应的差异.方法应用红外线热像技术,采用不同的捻转补泻手法针刺健康人合谷穴后,观察其在即刻,10、20、30min,对局部皮肤温度的影响.结果不同捻转补法与泻法的操作存在着不同程度的效应差异,其中补法可以使皮温升高,泻法可以使皮温降低,以石氏捻转补泻针法较为明显.结论1)补泻手法,补法和泻法的操作可产生不同的效应.2)不同捻转补泻手法对皮肤温度产生的升降效应为补泻效应,其中以石氏捻转补泻手法最为明显.3)证明补泻手法实施的必要性.  相似文献   
997.
Enhancement of spontaneous killer cytotoxicity by soluble factor   总被引:1,自引:0,他引:1       下载免费PDF全文
Two-stage stimulation of SK activity of normal human peripheral blood lymphocytes by soluble factors was demonstrated. The first stage was initiated by factors present in supernatant derived from normal B-LCL cultures. Only cell lines which could induce SK activity in culture in an MLR-type reaction had the capacity to produce the active factor. Supernatant factor required adherent cells to cause SK augmentation. The interaction of adherent cells plus supernatant factor resulted in the production of a second soluble factor which stimulated an increase in SK activity in responding lymphocyte populations. This second stage involved a different soluble factor which acted directly on the non-SK, Fc-negative lymphocyte population, and within 3 hr. Data obtained using antisera to interferon (IF) indicated that IF is a component of the second soluble factor, and not of the supernatant factor derived from the B-LCL.  相似文献   
998.
We have recently reported that ligation of the CD44 cell surface antigen with A3D8 monoclonal antibody (mAb) triggers incomplete differentiation and apoptosis of the acute promyelocytic leukemia (APL)-derived NB4 cells. The present study characterizes the mechanisms underlying the apoptotic effect of A3D8 in NB4 cells. We show that A3D8 induces activation of both initiator caspase-8 and -9 and effector caspase-3 and -7 but only inhibition of caspase-3/7 and caspase-8 reduces A3D8-induced apoptosis. Moreover, A3D8 induces mitochondrial alterations (decrease in mitochondrial membrane potential DeltaPsi m and cytochrome c release), which are reduced by caspase-8 inhibitor, suggesting that caspase-8 is primarily involved in A3D8-induced apoptosis of NB4 cells. However, the apoptotic process is independent of TNF-family death receptor signalling. Interestingly, the general serine protease inhibitor 4-(2-aminoethyl)-benzenesulfonyl fluoride (AEBSF) decreases A3D8-induced apoptosis and when combined with general caspase inhibitor displays an additive effect resulting in complete prevention of apoptosis. These results suggest that both caspase-dependent and serine protease-dependent pathways contribute to A3D8-induced apoptosis. Finally, A3D8 induces apoptosis in all-trans-retinoic acid-resistant NB4-derived cells and in APL primary blasts, characterizing the A3D8 anti-CD44 mAb as a novel class of apoptosis-inducing agent in APL.  相似文献   
999.
Nineteen N-acyl-5-bromanthranilic acid amides were synthesized via acylation of 5-bromanthranilamide with suitable anhydrides. The antimicrobial activity of the synthesized compounds with respect to Staphylococcus aureus and Escherichia coli was evaluated. Compounds with diphenyl, furoyl, and tetrachlorophthalyl moieties in the acyl part of the molecule showed significant inhibition of microbial growth. The minimum inhibiting concentrations of this compounds were 15.6 μg/ml against S. aureus and 15.6 – 31 μg/ml against E. coli. Other tested amides were considerably less active.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 1, pp. 17 – 18, January, 2005.  相似文献   
1000.
Dose-response curves of angiotensin I (AI, 1.0-1000.0 pmol) and angiotensin II (AII, 1.25-1250.00 pmol) were obtained in isolated rat hearts subjected to control conditions, mild hypoxia (PO2 = 145 mm Hg), reoxygenation, ischemic (perfusion pressure = 35 mm Hg) and reperfusion. Both AI and AII caused dose-dependent coronary flow (CF) of 26 +/- 3 and 27 +/- 2%, respectively. The effects of both AI and AII were substantially attenuated during hypoxia, but were fully restored upon reoxygenation. During ischemia, the effect of AII was unaltered while the effect of AI was enhanced compared to the control (P less than 0.05). This enhancement was reversible on reperfusion. Cardiac conversion of AI, calculated from ED50 values for AI and AII, was significantly increased during ischemia (P less than 0.05). Infusion of saralasin (0.5-5.0 micrograms/min) did not increase CF in any of the groups. We conclude that (1) the coronary vasoconstrictive effect of AII is preserved in ischemia but attenuated in hypoxia and (2) cardiac conversion of AI to AII is enhanced in hearts injured by ischemia.  相似文献   
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