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941.
为探讨内耳辐射损伤的防治,采用丹参作为保护药物,用相同剂量的60Co γ射线照射丹参防护组和单纯放射组豚鼠耳颞部,2 周后作形态与机能检查。结果发现:丹参防护组耳蜗机能与结构损害较轻,而单纯放射组耳蜗机能明显受损,血管纹和柯替氏器病变严重;复合动作电位(CAP) 反应阈和毛细胞损伤率两组比较差异有显著性( P < 0 .01) 。表明丹参对内耳辐射损伤有保护作用。 相似文献
942.
目的 观察腹主动脉缩窄性高血压大鼠早期心脏原生型一氧化氮合酶基因表达及 L精氨酸对血压的影响。方法 14 ~16 周龄雄性 Wister 大鼠采用缩窄腹主动脉法制备高血压模型,口服 L精氨酸( 精氨酸组) 和未服 L精氨酸( 手术组) 的高血压大鼠及正常血压大鼠( 对照组) 在同样条件下喂养2 周后,测量血压,并采用逆转录多聚酶链反应技术检测一氧化氮合酶基因表达。结果 ①大鼠腹主动脉缩窄后发生严重的高血压且心脏一氧化氮合酶基因表达增强;②口服 L精氨酸2 周未能防止腹主动脉缩窄性高血压的发生。结论 腹主动脉缩窄性高血压大鼠早期心脏一氧化氮合酶基因表达增强; L精氨酸的降压作用可能具有选择性。 相似文献
943.
探讨体外射频热疗联合α受体阻滞剂治疗前列腺增生症(BPH)的安全性及近、远期疗效。方法采用随机对照方法。将90例有症状的BPH患者,随机分为3组,各30例。分别接受热疗(Ⅰ组)、受体阻滞剂(Ⅱ组)和热疗联合受体阻滞剂(Ⅲ组)等治疗。在18个月的随访期中,分期观察、比较各组的主、客观疗效。结果Ⅲ组近期(6个月以内)的主、客观疗效显著优与Ⅰ、Ⅱ组,远期疗效(6个月以上)优与Ⅰ组,但与Ⅱ组相当。结论体外射频热疗联合α受体阻滞剂是一种安全、简单和完全非侵入性的方法,对症状严重而无法手术的BPH患者,尤其适用。 相似文献
944.
目的 制备抗人尿激酶受体单克隆抗体,为今后uPAR 病理生理作用及临床意义的研究提供新的手段。方法 利用杂交瘤技术,用经PMA刺激的U937 细胞与可溶性尿激酶受体(suPAR)免疫Balb/c 小鼠,与SP2/0 细胞融合。结果 获得国内第1 组4 株抗人尿激酶受体(uPAR)单抗,分别命名为SZ- 98、SZ- 99 、SZ- 100 、SZ- 101。结论 4 株单抗均能与uPAR 特异性结合,能与U937 细胞及经PMA作用的K562 细胞反应。SZ- 101 与国外抗uPAR单抗3936 有相同的uPAR 结合位点;而SZ-98、SZ- 99 与SZ- 100 在uPAR上有不同的结合位点 相似文献
945.
目的了解我国供血员、受血者中经输血传播病毒(TTV)感染率,及经输血传播TTV的发生率。方法对130例输血者进行TTV以及HBV和HCV血清标志物检测,其相应的供血者也检查TTV。结果340例供血员中有36例(10.6%)可检测到TTV-DNA。130例受血者输血前有11例(8.5%)TTV阳性,其余119例输血后有18例TTV转为阳性,在他们的供血中至少可查到一份TTV阳性。46例输血后肝炎病毒感染者中,其中有45例为HCV感染(包括7例与TTV混合感染),2例为HBV感染(包括与HCV、TTV混合感染各1例)。TTV与HBV混合感染以及7例TTV与HCV混合感染中有3例的受血者ALT>90U/L,但是10例单纯TTV感染者,仅有2例伴有轻微的ALT增高。结论供血员及住院病人中有较高的TTV感染率,单纯TTV感染与ALT显著升高似乎并无关联。 相似文献
946.
OBJECTIVE: The purpose of this study was to evaluate the effectiveness of CT colonography when patients were imaged in both the supine and prone positions. We evaluated whether imaging in two positions decreased the number of collapsed colonic segments and increased sensitivity for polyp detection. MATERIALS AND METHODS: Twenty-three patients underwent CT colonography in both the supine and prone positions. Colonic distention for each of the 46 scans was graded. Adequacy of distention for either position alone was compared with that of the combination of the two positions. Polyp data revealed by colonoscopy were reviewed, and the CT data were then retrospectively reviewed for polyp detection. RESULTS: When each scan was considered alone without benefit of the scan obtained in the opposite position, 27 (58.7%) of 46 scans showed inadequate distention. When scans obtained in both positions were considered together, 20 (87.0%) of 23 patients had adequate distention with the grading system used. However, this value increased to 23 (100%) of 23 patients when the reasons for inadequate distention in the three patients were considered. Of the 27 polyps detected with colonoscopy, 21 (77.8%) were also detected retrospectively with CT colonography. Colonoscopy showed 20 polyps that were 5 mm or larger; nineteen (95.0%) of these 20 polyps were also detected retrospectively with CT colonography, nine (47.4%) of which were seen in only one position. CONCLUSION: Use of both the supine and prone positions for patients undergoing CT colonography improves evaluation of the colon and increases sensitivity for polyp detection. 相似文献
947.
G Bartzokis I B Goldstein D B Hance M Beckson D Shapiro P H Lu N Edwards J Mintz P Bridge 《AJNR. American journal of neuroradiology》1999,20(9):1628-1635
BACKGROUND AND PURPOSE: Cocaine and its metabolites can produce vasospasm, and cocaine-dependent patients are at increased risk for stroke. Based on previous case reports, we hypothesized that the incidence of hyperintense brain lesions observed on T2-weighted MR images would also be increased in asymptomatic cocaine-dependent individuals. METHODS: Sixty-two male "crack" (smoked) cocaine-dependent participants ranging in age from 25 to 66 years were compared with 116 normal male control participants ranging in age from 25 to 80 years. Those with histories of neurologic symptoms or illnesses were excluded. The severity of hyperintense lesions was rated on a 0- to 3-point scale, and ratings of 3 were used in the data analysis as an indicator of a probable pathologic process. Three regions were separately rated: the cerebral white matter, insular subcortex white matter, and subcortical gray matter (basal ganglia and thalamus region). RESULTS: Significantly increased risk of severe lesions was observed in the two white matter regions of the cocaine-dependent group (odds ratio of 16.7 and 20.3) but not in the subcortial gray matter region (odds ratio of 1.4). In the insula subcortex white matter, the risk of lesions increased with age in the cocaine-dependant sample, but remained essentially absent among normal controls through the age of 80 years. In the cerebral white matter, the relationship of age and risk of lesion among normal participants was similar in shape to that in cocaine-dependent participants, but equivalent risk was seen 20 years earlier among cocaine-dependent participants. CONCLUSIONS: Cocaine-dependent participants had a significantly increased age-related risk of white matter damage. The possible clinical implications of this damage are discussed. 相似文献
948.
949.
Ebraheim NA Lu J Haman SP Yang H Yeasting RA 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》1999,20(2):108-111
The surface area, thickness, and composition of the articular cartilage of the peroneocuboid articulation and the location of the synovium were investigated in 15 cadaver foot specimens. The articulations of the medial side of the peroneus longus tendon and lateral side of the cuboid were covered with fibrous and hyaline cartilages, respectively. On the lateral tuberosity of the cuboid, there is a facet that has 79.37+/-20.24 mm2 articular cartilage area with an oval shape to conform to that of the articular surface of the peroneus longus tendon (articular cartilage area, 67.35+/-28.53 mm2) with which it articulates. The mean thickness of the articular cartilage of the peroneus longus tendon and cuboid was 0.34+/-0.08 and 0.52+/-0.07 mm, respectively. The peroneocuboid joint has its own joint capsule. The synovial cavity does not communicate with the sheath of the peroneus longus tendon. Synovial membranes were attached to the margins of the articular surfaces of the cuboid immediately peripheral to the cartilage region. 相似文献
950.
Leptin-induced increase in sympathetic nervous and cardiovascular tone is mediated by proopiomelanocortin (POMC) products 总被引:3,自引:0,他引:3
The mechanism underlying the leptin-induced increased sympathetic nerve activity and cardiovascular tone was investigated in normal rats. The melanocortin (MC) peptides and other fragments derived from proopiomelancortin (POMC) have a diverse array of biological activities and have been implicated in mediating the feeding behavioral responses to leptin. In this study we evaluated the possible involvement of two major products of POMC, alpha-melanocyte stimulating hormone (alpha-MSH) and beta-endorphin, in mediating the effects of leptin on sympathetic activity and mean arterial pressure (MAP) in normal rats. Intraventricular (i.c.v.) cannulas were implanted in normal rats and allowed to recover. On the day of the study the animals were anesthetized with urethane alpha-chloralose and instrumented for the recording of MAP, lumbar sympathetic nerve activity (LSNA), and heart rate (HR). To determine the correlation between the leptin response and the POMC products, alpha-MSH and beta-endorphins were also injected into the lateral ventricle. alpha-MSH acted to increase MAP and LSNA while beta-endorphin decreased these parameters. Leptin administration by i.c.v. cannula increased the MAP and LSNA in normal rats. The i.c.v. administration of agouti protein, an alpha-MSH receptor antagonist, prior to leptin infusion blocked this response. Likewise, pretreatment with naloxone a beta-endorphin receptor antagonist also blocked the response to leptin. From these studies we conclude that the acute increased LSNA and MAP in response to i.c.v. leptin may be mediated by increased POMC and its subsequent production of breakdown product alpha-MSH and/or beta-endorphin and it is the subsequent action of alpha-MSH that increases MAP and LSNA by activation of the MC4 receptor. The naloxone antagonism of the leptin response is likely due to the blockade of presynaptic opioid inhibition of the MC4 receptor-mediated pressor response. 相似文献