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81.
椎基底动脉短暂缺血性眩晕患者脑血流量与脑干听力诱发电位的关系研究 总被引:2,自引:0,他引:2
为探讨椎基底动脉短暂缺血性眩晕 (VBTIV)患者的脑干听力诱发电位 (BAEP)与脑血流量 (CBF)和病理改变的关系 ,对 6 5例 VBTIV患者 (患者组 )作磁共振血管成像 (MRA)、经颅多普勒 (TCD)和 BAEP检查 ,对 2 6例对照组患者作 MRA和 TCD检查。结果 :MRA显示患者组 5 0例血管病理改变明显 ,1 5例改变不明显或无改变 ;对照组脑血流量为 1 1 2 .3~ 2 78.9ml/ min(2 s) ,较患者组 48.0~ 2 6 2 .0 m l/ min高 (P<0 .0 1 ) ,患者组 1 5例脑血流量下降 ,5 0例脑血流量正常 ;患者组 BAEP异常 47例 (72 .3% ) ,其中 ,1 5例脑血流量下降者 ,1 4例(93.3% ) BAEP异常 ,比 5 0例脑血流量正常者中的 33例 (6 6 % ) BAEP异常高 (P<0 .0 5 ) ;5 0例血管病理改变明显者 ,BAEP异常 40例 (80 % ) ,比 1 5例血管病理改变轻或无改变者中的 7例 (43.3% ) BAEP异常高 (P<0 .0 5 ) ,说明BAEP与 CBF和血管病理改变密切相关 相似文献
82.
The changes of type I collagen in the lung tissues of rats with hypoxic pulmonary hypertension (HPH) and its relationship to the mean pulmonary arterial pressure (mPAP) were investigated. The blood dynamic indexes of pulmonary circulation were measured by using Swan-Ganz. The distribution of type I collagen in pulmonary arteries, bronchi and plumonary interstitial was observed by using streptavidin peroxidase method (SP). The morphologic changes of small pulmonary arteries and the level of type I collagen were determined by image pattern analysis technique and gray scale scanning, respectively. The results showed, compared with the controls, mPAP of the hypoxic rats elevated (from 2.12 +/- 0.25 to 3.95 +/- 0.43 kPa, P < 0.01), their small pulmonary arteries, walls thickened (MT% from 16.35 +/- 2.64 to 35.83 +/- 3.55, MA% from 26.83 +/- 3.40 to 59.68 +/- 4.90, P < 0.01) and lumen narrowed. The distribution of type I collagen was mainly in the external layer of pulmonary arterial walls; the positive degrees of gray scale scanning increased and had a positive linear relationship to the mPAP and MT%. These findings suggest that the increase of type I collagen contents in pulmonary arteries is closely related to the development of HPH. 相似文献
83.
关节灵片镇痛、抗炎作用的实验研究 总被引:1,自引:0,他引:1
为探讨关节灵片的镇痛、抗炎作用,用热板法和扭体法观察该药镇痛作用,结果关节灵片为不同剂量灌胃给药对小鼠热致痛和醋酸致痛均有明显抗痛作用,呈现一定的量效关系;关节灵片对二甲苯所致炎性水肿亦有显著的抑制作用。提示关节灵具有较好的镇痛抗炎作用。 相似文献
84.
目的:评价CT在腺肿瘤中诊断及鉴别诊断的价值。方法:通过回顾性分析42例经术后病理证实的腮腺肿瘤的CT表现及其术前诊断,并与病理诊断进行对照分析。结果:27例良性肿瘤中,有24例CT表现为类圆形肿块,边界清楚,密度均匀,有3例密度欠均匀,边界模糊;15例恶性肿瘤中,12例CT为边界不清,密度不均匀,3例密度均匀,边界较清晰。术前CT诊断对85.71%腮腺肿瘤可作出定性诊断,但对其组织类型不能确认。 相似文献
85.
Yapu Cao Kaixiang He Qingqing Li Xin Chen Haiying Mo Zhihao Li Qiaolin Ji Ganpeng Li Gang Du Haiying Yang 《Journal of basic microbiology》2023,63(1):17-25
Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant–fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway. 相似文献
86.
Psychometric validation of the revised Functional Assessment of Human Immunodeficiency Virus Infection (FAHI) quality of life instrument 总被引:4,自引:0,他引:4
The revised Functional Assessment of Human Immunodeficiency Virus Infection (FAHI) quality of life (QoL) instrument has been updated and expanded to provide more complete and accurate coverage of human immune deficiency virus/ acquired immune deficiency syndrome (HIV/AIDS)-related QoL. Factor analysis and the Rasch measurement model were used to determine a new subscale structure for the FAHI. The content of these subscales, including physical well-being (ten items, = 0.91), function and global well-being (13 items, = 0.86), emotional well-being/living with HIV (10 items, = 0.82), social well-being (eight items, = 0.73), and cognitive functioning (three items; = 0.75), reflect both general illness- and HIV/AIDS-specific QoL concerns: a total QoL score can also be calculated for the FAHI (44 items, =0.91). Psychometric evaluation revealed good internal consistency reliability for the FAHI and its subscales. In addition, construct validity, known groups validity and sensitivity to change were demonstrated by significant associations between the FAHI and additional indicators of functional status, psychological symptoms, stress and illness severity. In summary, the FAHI is a psychometrically sound instrument that captures multiple important dimensions of HIV/AIDS-related QoL. It is brief, easy to administer and score, has been translated into nine languages other than English and is appropriate for use in clinical trials and clinical practice. 相似文献
87.
Apoptosis and cell-cycle arrest in human and murine tumor cells are initiated by isoprenoids 总被引:9,自引:0,他引:9
Diverse classes of phytochemicals initiate biological responses that effectively lower cancer risk. One class of phytochemicals, broadly defined as pure and mixed isoprenoids, encompasses an estimated 22,000 individual components. A representative mixed isoprenoid, gamma-tocotrienol, suppresses the growth of murine B16(F10) melanoma cells, and with greater potency, the growth of human breast adenocarcinoma (MCF-7) and human leukemic (HL-60) cells. beta-Ionone, a pure isoprenoid, suppresses the growth of B16 cells and with greater potency, the growth of MCF-7, HL-60 and human colon adenocarcinoma (Caco-2) cells. Results obtained with diverse cell lines differing in ras and p53 status showed that the isoprenoid-mediated suppression of growth is independent of mutated ras and p53 functions. beta-Ionone suppressed the growth of human colon fibroblasts (CCD-18Co) but only when present at three-fold the concentration required to suppress the growth of Caco-2 cells. The isoprenoids initiated apoptosis and, concomitantly arrested cells in the G1 phase of the cell cycle. Both suppress 3-hydroxy-3-methylglutaryl CoA reductase activity. beta-Ionone and lovastatin interfered with the posttranslational processing of lamin B, an activity essential to assembly of daughter nuclei. This interference, we postulate, renders neosynthesized DNA available to the endonuclease activities leading to apoptotic cell death. Lovastatin-imposed mevalonate starvation suppressed the glycosylation and translocation of growth factor receptors to the cell surface. As a consequence, cells were arrested in the G1 phase of the cell cycle. This rationale may apply to the isoprenoid-mediated G1-phase arrest of tumor cells. The additive and potentially synergistic actions of these isoprenoids in the suppression of tumor cell proliferation and initiation of apoptosis coupled with the mass action of the diverse isoprenoid constituents of plant products may explain, in part, the impact of fruit, vegetable and grain consumption on cancer risk. 相似文献
88.
细胞核因子NF-кB在肿瘤血管生成中可能具有核心调节作用,本文选择80例有随访结果的骨肉瘤,应用免疫组化方法检测 NF-кB p65亚单位以及血管内皮细胞生长因子(VEGF)的表达,同时观察肿瘤内微血管密度(MVD),旨在探讨 NF-кB表达与骨肉瘤血管生成的关系。结果:80例骨肉瘤中 48例 NF-кB p65阳性,阳性产物主要定位于肿瘤细胞浆。NF-кB表达与VEGF表达和MVD呈显著正相关,而且NF-кB阳性组病人存活时间显著低于阴性组。该结果表明:①NF-кB p65是骨肉瘤相关的一种癌蛋白,在骨肉瘤的发生和发展中发挥重要的作用;②NF-кB对VEGF可能有正向调节作用,进而影响骨肉瘤血管生成;③NF-кB 对肿瘤血管生成的作用,可能是影响骨肉瘤预后的主要原因之一。 相似文献
89.
软骨提取液成分分析及降血脂和抗过氧化实验研究 总被引:3,自引:0,他引:3
目的:为探讨动物软骨调节血脂和延缓衰老的作用。方法:交猪关节软骨碱降解及酶降解制得提取液,进行成分分析及动物实验。结果:猪软骨提取液中含有丰富的酸性粘多糖和氨基酸及人体必需微量元素,能显著降低大鼠血清TC和TG和显著升高大鼠体内超氧化物歧化酶(SOD)活性并降低血清脂质过氧化物(LPO)水平,结论:猪软骨提取液有一定的保健作用。 相似文献
90.
应用CD3AK细胞预防肝癌术后复发的初步观察 总被引:4,自引:0,他引:4
目的 观察CD3AK细胞治疗对肝癌术后复发的影响。方法 62例肝癌切除术按序列单双数的原则分为两组,研究组32例术后1周开始应用CD3AK细胞治疗,每隔2~3个月施行一疗程,共2~6个疗程;对照组30例术后不用CD3AK细胞治疗,仅作一般护治疗。结果 ①研究组术后1年复发率6.3%(2/32)明显低于对照组26.7%(8/30)(P〈0.05);②研究组和对照组术后4周免疫功能有明显差异(P〈0. 相似文献