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81.
熔覆层中的颗粒相分布不仅影响材料性能,同时也是研究熔覆过程各种反应机制的主要依据。本文利用图像分析技术,定量分析了Q235钢表面Cu5%Al激光熔覆层的富铁相颗粒分布情况。发现熔覆过程中在熔池中存在熔体对流环,熔池中的对流带动颗粒运动,是决定熔覆层颗粒分布的主要因素。 相似文献
82.
养血清脑颗粒治疗老年期痴呆的临床疗效观察 总被引:1,自引:0,他引:1
目的:观察养血清脑颗粒对老年期痴呆的疗效。方法:治疗组老年期痴呆患者36例均应用养血清脑颗粒。详录治疗前后实验室检查数据。健康老年人34例为对照组,以其体检时所得相关指标与治疗组比较分析。结果:有效率85%,S-TC明显下降,P-SOD明显升高,P-LPO,Ht,Va降低、EET缩短。结论:养血清脑颗粒具有降脂、抗自由基损伤。改善异常血液流变,增加脑血流量等功用。对老年期痴呆防治有较好效果。 相似文献
83.
The mechanisms associated with metallothionein (MT) gene regulation are complex and poorly understood. Only a modest increase in brain MT expression levels is attained by exposure to metals, MT gene transfection, and MT gene knock-in techniques. Accordingly, in the present study, MT null astrocytes isolated from transgenic mice deficient in MT-I and MT-II genes were introduced as a zero background model of MT expression. MT protein levels were determined by western blot analysis. MT proteins in MT-I and MT-II null astrocytes were undetectable. Transient MT-I gene transfection increased the levels of foreign MT expression in MT-I and MT-II null astrocytes by 2.3-fold above basal levels in wild-type astrocytes. Intracellular Na(2)51CrO(4) efflux and D-[2,3-3H]aspartate uptake were studied as indices of acute methylmercury (MeHg) (5 microM) cytotoxicity. In MT-I and MT-II knockout astrocytes MeHg led to significant (p<0.01) increase in Na(2)51CrO(4) efflux and a significant (p<0.05) decrease in the initial rate (1 min) of D-[2, 3-3H]aspartate uptake compared to MT-I and MT-II knockout controls. Transfection of the MT-I gene in MT-I and MT-II null mice significantly (p<0.01) decreased the effect of MeHg on Na(2)51CrO(4) efflux in MT null, as well as wild-type astrocytes. MT-I gene transfection in MT-I and MT-II null astrocytes reversed the inhibitory effect of MeHg on D-[2,3-3H]aspartate uptake, such that initial rates of uptake in MT-I transfected cells in the presence and absence of MeHg (5 microM) were indistinguishable. These results demonstrate that: (1) astrocytes lacking MTs are more sensitive to MeHg than those with basal MT protein levels, (2) the MT-I gene can be overexpressed in MT-I and MT-II null astrocytes by transient MT-I gene transfection, and (3) that foreign MT expression endows astrocytes with increased resistance to MeHg. 相似文献
84.
目的 :探讨多种肿瘤标志物对卵巢癌的诊断价值。方法 :应用化学发光法测定卵巢肿瘤、子宫内膜异位症和盆腔炎性包块的CA1 2 5、CA1 99、CA1 5 3、AFP、CEA阳性率。结果 :卵巢癌患者中 ,80 .6 0 %CA1 2 5阳性 ,92 .5 3%联合检测阳性 ,阳性率明显高于良性肿瘤、子宫内膜异位症、盆腔炎性包块患者 (P <0 .0 1 ) ;CA1 2 5与卵巢癌的临床分期及病理类型无关 ,但Ⅰ期卵巢癌患者的血清CA1 2 5值明显低于Ⅱ~Ⅳ期患者 (P <0 .0 1 )。结论 :CA1 2 5对卵巢癌的诊断有一定的价值 ,联合监测能提高卵巢癌的诊断率 ,尤其对早期卵巢癌。 相似文献
85.
Psychometric evaluation of the Taiwan version of the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire. 总被引:2,自引:0,他引:2
BACKGROUND AND PURPOSE: To adapt the Taiwan version of the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire and evaluate its psychometric properties. METHODS: The DASH questionnaire was adapted through the process of translation, back-translation, and expert review. Eighty two subjects with upper extremity disorders were recruited in a medical center and 46 of these patients could be followed up to assess retest reliability in less than 10 days. Cronbach alpha and intraclass correlation coefficient were used to evaluate the internal consistency and test-retest reliability. Principal axis factor analysis was performed to assess the factor-construct validity, while concurrent validity was tested with the Medical Outcomes Study Short Form-36 (SF-36) Taiwan version questionnaire. RESULTS: The internal consistency of the Taiwan version of the DASH questionnaire was high (Cronbach alpha = 0.96) and the test-retest reliability was satisfactory (intraclass correlation coefficient = 0.9). Principal axis factor analysis confirmed the 1-factor model. The Pearson correlation coefficients of the DASH questionnaire to the SF-36 showed a correlation with physical component summary scores rather than mental component summary scores. Bodily pain, physical function and role-physical scores among the SF-36 subscales were most significantly correlated with DASH disability/symptom scores. CONCLUSION: The Taiwan version of the DASH questionnaire is a valid and reliable measure of health status for patients with upper-extremity disorders. 相似文献
86.
目的探讨心脏直视手术后神经系统并发症发生的原因、预防措施及救治体会。方法回顾性分析心脏直视手术后18例神经系统并发症的临床表现及诊治过程。结果18例中,一过性的神经精神功能紊乱13例,中枢神经系统功能障碍4例;经治疗,1例死亡,17例患者均痊愈出院,随访中,有2例留下后遗症。结论引发体外循环心脏直视手术后神经系统并发症的主要原因是脑栓塞和脑氧供需失衡、年龄偏大、原有神经系统疾病和糖尿病、术前心功能差、大动脉病变及体外循环时间长等,治疗方法以支持性为主,消除脑组织本身所发生破坏性反应,此外,可以通过改进各项技术措施加以预防。 相似文献
87.
Objective: To study the effects of kadsurenone on inflammatory mediators Platelet-activating factor (PAF), tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) in rat model of acute pancreatitis(AP). Methods: SD male rats (104) were randomly divided into sham group (n = 24), AP group (n = 40) and kadsurenone group (n = 40). The rats were killed 3, 6, 12 and 24 hours after operation. The serum level of PAF, TNF-α and IL-6 was measured. Results: The serum level of PAF, TNF-α and IL-6 of AP group was significantly increased(P 〈 0.01 )compared with control group. The serum level of TNF-α got to a peak 6 hours after operation, and the serum IL-6 getting to a peak 12 hours after operation in AP group. After kadsurenone was administered to AP rats, pancreas and lung myeloperoxidase (MPO), serum amylase activity was reduced. Histology showed a trend toward improvement. The serum level of PAF, TNF-α and IL-6 was significantly decreased (P 〈 0.05). Conclusion. Kadsurenone can reduce the severity of systemic inflammation in rats with AP and relieve the damage of the pancreas and lung in AP rats. These results suggested that kadsurenone may be useful in the treatment of acute pancreatitis. 相似文献
88.
10年间妊娠合并糖尿病发生状况及母儿结局的变化 总被引:2,自引:0,他引:2
目的探讨10年间妊娠合并糖尿病发生状况及母儿结局的变化,并分析其原因。方法近10年我院妊娠合并糖尿病孕妇共计58例,将其分成两组,1994年1月~1998年12月前5年19例患者作为A组,1999年1月~2003年12月后5年39例患者作为B组,对两组资料中孕妇一般情况、病情严重程度、治疗情况及分娩方式、围产儿并发症等情况进行比较分析和统计学处理。结果①A组孕妇孕晚期体重指数(BMI)、年龄、正规产检率、无症状患者均明显低于B组,其确诊孕周晚于B组;②A组治疗前空腹血糖值、酮症酸中毒发生率、早产率均高于B组;③A组单纯饮食控制不佳需加用胰岛素者及血糖控制不良率高于B组,A组经阴道产钳助产率亦高于B组;④A组围产儿并发症,死胎发生率、新生儿窒息率、IRDS发生率均高于B组。结论妊娠合并糖尿病对母儿可造成多种危害,近5年妊娠合并糖尿病发生率虽上升,但母儿并发症并未相应增多,与孕妇健康意识增强、孕期进行筛查,早发现,早治疗密切相关。 相似文献
89.
输卵管妊娠术后生殖状况及其影响因素分析 总被引:37,自引:0,他引:37
目的分析引起输卵管妊娠手术治疗后不同生殖状况的相关因素,探讨改善生殖状况,提高宫内妊娠率的方法.方法对自1999-01-2003-12在中山大学附属第一医院等两家医院的424例输卵管妊娠患者经腹腔镜或剖腹手术治疗后患者生殖状况及其相关影响因素进行多重Logistic回归分析及x2分析,找出引起术后不孕及重复性异位妊娠的原因.结果424例患者术后宫内妊娠177例,占41.7%;出现重复性异位妊娠102例,占24.1%;有145例患者术后仍然未孕,占34.2%.多重Logistic回归分析提示,盆腔炎、不孕、异位妊娠、输卵管手术、输卵管粘连、输卵管伞端闭锁是输卵管妊娠术后不孕及重复性异位妊娠的危险因素.结论积极预防盆腔病变,治疗不孕症是改善输卵管妊娠术后生殖状况的重要手段. 相似文献
90.
Previous studies in schizophrenia have shown alterations in membrane phospholipids and polyunsaturated fatty acids. However, these studies have primarily examined peripheral (non-neuronal) cell types. The purpose of the present study was to examine whether the membrane deficits seen in peripheral tissues are also observed in the brain. The caudate was the primary region of interest for this study. Using high-pressure liquid chromatography in conjunction with an evaporative light-scattering detector, we first measured the level of various membrane phospholipids (PL) in schizophrenic (n=11) and control groups with (n=7) and without (n=14) other mental disorders. Polyunsaturated fatty acids (PUFAs) were then determined by capillary gas chromatography. Within groups, there are no significant correlations between membrane PL levels and other collection and demographic parameters including age, postmortem interval, storage time and brain weight. Significantly lower amounts of phosphatidylcholine and phosphatidylethanolamine were found in postmortem brain tissue from schizophrenic patients than in those from control groups, even after accounting for potential confounds. In addition, strong reductions of total PUFAs and saturated fatty acids were found in schizophrenic brains, relative to control brains. Specifically, the reduced PUFAs were largely attributable to decreases in arachidonic acid (AA) and, to a lesser extent, its precursors, linoleic and eicosadienoic acids. There are no significant differences between the control groups with and without other mental disorders. The present findings suggest that deficits identified in peripheral membranes may also be present in the brain from schizophrenic patients. Such a deficit in membrane AA may contribute to the many biological, physiological, and clinical phenomena observed in schizophrenia. 相似文献