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51.
52.
三味中药配伍应用对改善烫伤小鼠受损免疫功能的作用 总被引:1,自引:0,他引:1
目的 观察对烫伤小鼠受损免疫功能具有调理作用的单味中草药 ,经过配伍应用后的协同作用。方法 采用 1 .0 3 4× 1 0 5 Pa的蒸气烫伤 1 0s ,烫伤面积 1 6% ,深度为Ⅲ度的致伤模型烫伤动物。通过观察MΦ的吞噬功能、枯否细胞清除能力、MΦ抗原提呈功能、血清TNF量、淋巴细胞增殖反应及IL 2产生能力、小鼠抗体产生能力、PMNH2 O2 释放量及PMN溶菌酶释放量、血清补体的趋化作用和聚集作用等指标 ,籍以了解单味中药与配伍中药对烧 (烫 )伤小鼠受损免疫功能的调理作用。结果 单味中药三七(PP) ,金银花 (LJ)和虎杖 (PC)对小鼠受损免疫功能有一定的改善作用。PC +LJ、PP +PC、PP +LJ等二味配伍的中药 ,除少数指标外 ,均比单味药的作用好。而PP +LJ+PC三味配伍药的调理作用 ,比单味药和二味配伍药的调理作用更佳。结论 单味中药经配伍应用后对烧 (烫 )伤小鼠严重受损的免疫系统功能 ,具有比单味药更好的协同调理作用。 相似文献
53.
妊娠期雌二醇和催乳素与瘦素的关系 总被引:2,自引:0,他引:2
目的 研究妊娠期间性激素与瘦素水平之间的关系。方法 在180例不同孕周的妇女中,按孕周分为<20周组,20-23周组,≥28周组,采用酶联免疫吸附法测定其外周血血清雌二醇(E2)和催乳素(PRL),放射免疫法测定血清瘦素水平,分析这些激素之间的相互关系。结果 E2和PRL均随妊娠进展而逐步升高(P<0.0001),组间均有显著差异(P<0.05)。各组瘦素水平均高于非妊娠组,但组间差异无显著性。瘦素水平与孕妇体重及体重指数显著相关(P0.01),与PRL也呈相关(P<0.05),而与E2无明显相关。结论 PRL水平与妊娠期瘦素水平升高有一定关系。 相似文献
54.
不同地区妇女产褥期卫生行为研究 总被引:22,自引:0,他引:22
目的 了解江苏、陕西和贵州三省妇女产褥期卫生行为和保健的一般情况;比较 不同地区间产褥期各种卫生行为的发生率;了解影响产褥期卫生行为的相关因素。方法 用问卷调查的形式对三者12个县的2352例2岁以下儿童母亲进行入户访问。结果 江苏、陕西、贵州三者产褥期各卫生行为的发和衣次为:洗头26.4%,38.8%,19.8%, 下身(指外阴部,下同)83.3%,26.9%,64.0%,正常活动76.9%,7 相似文献
55.
目的:探讨P75NGFR介导神经细胞凋亡的分子机制。方法;以转染了P75NGFR的大鼠小脑神经细胞株R2L2为细胞模型,应用酵母双向杂交系统(two-hybrid system)筛选和鉴定P75NGFR胞内区P75ICD作用的蛋白。结果:和P75NGFR作用的蛋白由一个600bp大小的CDNA片段编码。结论:该工作将有助于探讨P75NGFR介导细胞凋亡的分子机制和信号,为勃勃系统退行性病变的病因、 相似文献
56.
57.
大鼠局灶性脑缺血模型及其与C反应蛋白变化的关系 总被引:34,自引:1,他引:33
目的 改进大鼠大脑中动脉梗塞法,建立更接近于临床缺血性脑卒中及其再扩灌注的可靠模型,并观察其与血甭C反应蛋白变化的。方法沿大鼠右颈内动脉插入长2.1 ̄2.3cm直径0.205mm的单股尼龙丝,直达大脑中动脉起始部开口,阻断其血流,观察大鼠神经病学改变及脑组织形态学变化,并测定血清C反应蛋白含量。结果 术后大鼠表现特殊体态及典型追尾征,6h大脑中动脉供血区出现缺血性外观(TTC染色)及相应组织学变化 相似文献
58.
Computerized analysis of lesions in US images of the breast 总被引:1,自引:0,他引:1
Giger ML Al-Hallaq H Huo Z Moran C Wolverton DE Chan CW Zhong W 《Academic radiology》1999,6(11):665-674
RATIONALE AND OBJECTIVES: Breast sonography is not routinely used to distinguish benign from malignant solid masses because of considerable overlap in their sonographic appearances. The purpose of this study was to investigate the computerized analyses of breast lesions in ultrasonographic (US) images in order to ultimately aid in the task of discriminating between malignant and benign lesions. MATERIALS AND METHODS: Features related to lesion margin, shape, homogeneity (texture), and posterior acoustic attenuation pattern in US images of the breast were extracted and calculated. The study database contained 184 digitized US images from 58 patients with 78 lesions. Benign lesions were confirmed at biopsy or cyst aspiration or with image interpretation alone; malignant lesions were confirmed at biopsy. Performance of the various individual features and output from linear discriminant analysis in distinguishing benign from malignant lesions was studied by using receiver operating characteristic (ROC) analysis. RESULTS: At ROC analysis, the feature characterizing the margin yielded Az values (area under the ROC curve) of 0.85 and 0.75 in distinguishing between benign and malignant lesions for the entire database and for an "equivocal" database, respectively. The equivocal database contained lesions that had been proved to be benign or malignant at cyst aspiration or biopsy. Linear discriminant analysis round-robin runs yielded Az values of 0.94 and 0.87 in distinguishing benign from malignant lesions for the entire database and for the equivocal database, respectively. CONCLUSION: Computerized analysis of US images has the potential to increase the specificity of breast sonography. 相似文献
59.
Zhou XF Deng YS Chie E Xue Q Zhong JH McLachlan EM Rush RA Xian CJ 《The European journal of neuroscience》1999,11(5):1711-1722
Injury to a peripheral nerve induces in the dorsal root ganglia (DRG) sprouting of sympathetic and peptidergic terminals around large-diameter sensory neurons that project in the damaged nerve. This pathological change may be implicated in the chronic pain syndromes seen in some patients with peripheral nerve injury. The mechanisms underlying the sprouting are not known. Using in situ hybridization and immunohistochemical techniques, we have now found that nerve growth factor (NGF) and neurotrophin-3 (NT3) synthesis is upregulated in satellite cells surrounding neurons in lesioned DRG as early as 48 h after nerve injury. This response lasts for at least 2 months. Quantitative analysis showed that the levels of mRNAs for NT3 and NGF increased in ipsilateral but not contralateral DRG after nerve injury. Noradrenergic sprouting around the axotomized neurons was associated with p75-immunoreactive satellite cells. Further, antibodies specific to NGF or NT3, delivered by an osmotic mini-pump to the DRG via the lesioned L5 spinal nerve, significantly reduced noradrenergic sprouting. These results implicate satellite cell-derived neurotrophins in the induction of sympathetic sprouting following peripheral nerve injury. 相似文献
60.
Bone marrow transplantation attenuates murine IgA nephropathy: role of a stem cell disorder 总被引:4,自引:0,他引:4
Imasawa T Nagasawa R Utsunomiya Y Kawamura T Zhong Y Makita N Muso E Miyawaki S Maruyama N Hosoya T Sakai O Ohno T 《Kidney international》1999,56(5):1809-1817
BACKGROUND: The pathogenesis of IgA nephropathy is still obscure. The aim of this study was to investigate whether the fundamental pathogenesis of IgA nephropathy lies in bone marrow stem cells (BMCs). METHODS: We used donors of two different strains for bone marrow transplantation (BMT) into mice with a high content of serum IgA (ddY strain, HIGA mice), a murine model of IgA nephropathy. One group (B6-->HIGA, N = 5) received BMCs of C57BL/6j (B6) mice, and the other (HIGA-->HIGA, N = 8) were reconstituted with BMCs of HIGA mice. RESULTS: Twenty-six weeks after BMT, in B6-->HIGA mice, mesangial deposits of IgA and C3 were statistically milder than those in HIGA-->HIGA mice. Light microscopic observations disclosed that glomerular sclerosis and mesangial matrix expansion in B6-->HIGA mice were decreased compared with those in HIGA-->HIGA mice. These B6-->HIGA mice also excreted less urinary albumin than HIGA-->HIGA mice. Furthermore, serum levels of IgA in B6-->HIGA mice were markedly lower than those in HIGA-->HIGA mice. Size analysis of serum IgA revealed that macromolecular IgA were notably lower in B6-->HIGA mice than in HIGA-->HIGA mice. CONCLUSIONS: Our results suggest that qualitative and quantitative changes of serum IgA are determined at the level of stem cells, and that BMT from normal donors can attenuate glomerular lesions in HIGA mice. This approach may offer a new avenue to study the pathogenesis of IgA nephropathy. 相似文献