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971.
972.
We assessed the relation between different fasting plasma glucose (FPG) levels of 5.6 to 6.9 mmol/L and the prevalence and severity of angiographic coronary artery disease (CAD) in high-risk Chinese patients. Among 512 subjects who were to undergo coronary angiography for the confirmation of suspected myocardial ischemia, 409 subjects were enrolled and categorized into 3 groups based on FPG levels: (1) 相似文献   
973.
AIM: To investigate the effects of Danshao Huaxian (DSHX) capsules, a preparation of traditional Chinese medicine, on the expression of matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the fibrous livers of rats. METHODS: Eighty male Wistar rats were randomly divided into normal control group (group A), CCl4-induced hepatic fibrosis group (group B), non-DSHX-treated group (group C), low dose-treated group (group D), and high dose-treated group (group E). Fibrous liver models in rats were induced by subcutaneous injection of CCl4, oral administration of alcohol and high-lipid/low-protein diet for 8 wk. After the models were established, the rats in groups D and E were orally given a low dose (0.5 g/kg) and a high dose (1.0 g/kg) of DSHX daily for 8 wk, respectively. Then, the liver indexes, serum hyaluronic acid (HA) and alanine aminotransferase (ALT) were examined. The degree of hepatic fibrosis was evaluated by optical microscopy. Hydroxyproline (Hyp) in the urine was determined, and the expression of MMP-1 and TIMP-1 was detected by immunohistochemical techniques. RESULTS: In groups D and E, the liver indexes, levels of serum HA and ALT reduced and development of hepatic fibrosis weakened significantly. The urinary Hyp and expression of MMP-1 in the liver tissues elevated, but the expression of TIMP-1 decreased obviously, as compared to groups B and C. CONCLUSION: DSHX enhances the expression of MMP-1 but decreases that of TIMP-1 in liver tissues of CCl4-induced hepatic fibrotic rats, which may result in its elevated activity that contributes to fighting against hepatic fibrosis.  相似文献   
974.
To investigate differences in growth hormone (GH) and estrogen activation of insulin-like growth factor-I (IGF-I) expression, we have examined the effects of cycloheximide on hepatic and uterine IGF-I mRNA abundance in response to GH and 17 beta-estradiol (E2) respectively. In hypophysectomized (hypox) rats a single injection of GH significantly increased hepatic IGF-I mRNA 3.65 +/- 0.68-fold, P less than 0.005, 6 h after injection. Administration of cycloheximide 30 min prior to GH injection completely abolished this response. In contrast, in pituitary intact rats killed 6 h after administration of cycloheximide, hepatic IGF-I mRNA abundance was not significantly different from untreated control rats although the serum IGF-I concentration was significantly reduced; 119.9 +/- 11.8 vs. 270.2 +/- 48.7 ng/ml, P less than 0.005. In immature rats, injection of E2 (1 micrograms/100 g body weight) significantly increased uterine IGF-I mRNA 4.1 +/- 0.4-fold. Cycloheximide did not block the E2-induced increase in IGF-I mRNA but rather significantly enhanced the IGF-I response. These data indicate that continuing protein synthesis is required for GH induction of hepatic IGF-I mRNA in the hypox rat but is not required for E2 induction of uterine IGF-I mRNA. Furthermore, in pituitary-intact rats protein synthesis is not required for maintenance of hepatic IGF-I mRNA levels.  相似文献   
975.
J M Luo  L J Murphy 《Endocrinology》1989,125(1):165-171
Exogenous glucocorticoids are potent inhibitors of skeletal growth in experimental animals and children. The mechanism whereby glucocorticoids exert this effect is unclear, and circulating somatomedin levels have been reported to be low, normal, or high in this situation. Since recent studies have emphasized the importance of autocrine or paracrine insulin-like growth factor I (IGF-I), we have examined the effects of dexamethasone (DXM) on IGF-I gene expression in the hypophysectomized (hypox) and pituitary intact rat. An increase in IGF-I messenger RNA (mRNA) abundance of approximately 5-, 3-, 2-, and 1.5-fold in the liver, proximal tibia, lung, and kidney, respectively, was seen in hypox rats killed 6 h after injection of human GH (100 micrograms/100 g body wt). As little as 1 micrograms/100 g body wt of DXM administered 3 h before GH injection significantly reduced GH induction of IGF-I mRNA in the liver and the proximal tibia (P less than 0.05 and P less than 0.005, respectively). Higher doses of DXM were required to reduce IGF-I mRNA abundance in the kidney and lung. Of the tissues examined the order of sensitivity to DXM was liver greater than tibia greater than kidney greater than lung. In contrast to the effects of DXM on tissue IGF-I mRNA abundance, an approximately 10-fold higher dose of DXM was required to inhibit the GH-induced rise in serum IGF-I concentration. The effect of DXM on steady state IGF-I mRNA abundance in pituitary-intact rats which were killed 9 h after DXM was also examined. The reduction in IGF-I mRNA abundance required higher doses of DXM (6-360 micrograms/100 g body wt) and was less marked in pituitary-intact rats than in GH-treated hypox rats. In the pituitary-intact rats the order of sensitivity to DXM was tibia greater than liver greater than lung greater than kidney. In acute studies serum IGF-I levels were not decreased by any dose of DXM; rather a significant increase in serum IGF-I was apparent in pituitary intact rats, treated with the lowest and highest doses of DXM. When DXM was administered daily for 6 days to pituitary intact rats, body wt gain and hepatic and tibial IGF-I mRNA abundance were significantly reduced. No significant changes were seen in serum IGF-I concentrations.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
976.
目的采用超声造影定量分析技术监测肾缺血再灌注损伤发生后早期兔肾皮质血流灌注的改变。方法 36只家兔随机分为假手术组(R0组)、缺血后再灌注第2小时组(R1组)、第16小时组(R2组)、第24小时组(R3组),每组各9只。行超声造影并应用时间-强度曲线(TIC)测量灌注峰值时间(TTP)、曲线上升支斜率(β)、灌注峰值强度(A)、曲线下面积(AUC),观察各参数的变化并对比与兔肾病理改变的相关性。结果肾缺血恢复灌注后各组与对照组相比TTP、AUC增大,β值、A值降低(P<0.05);缺血再灌注组各组间TTP、β有统计学差异(P<0.05),其中恢复灌注后第24 h的TTP的延长和β的下降最为显著(P<0.01)。结论 肾缺血再灌注损伤早期即发生肾皮质微循环障碍,超声造影定量分析技术能敏感反映这一过程。TIC曲线各定量参数对于评价肾局部微循环灌注具有参考价值,其中TTP及β更具意义。  相似文献   
977.
化疗相关认知功能障碍是肿瘤患者在化疗中或化疗后出现的认知下降的现象。这不仅严重影响患者的生活质量,还会影响患者重返职场工作。本文介绍目前乳腺癌化疗相关认知功能损伤的概况、可能发生机制、评估手段、影像学发现及治疗方面的研究进展,并对该领域今后的研究方向进行了展望。  相似文献   
978.
经皮肾镜取石术(PCNL)是通过超声或X线定位经皮穿刺至肾脏扩张后建立操作通道,击碎并取出结石,目前已完全取代开放手术,成为治疗肾及输尿管上段结石的一线选择方法,由于其具有创伤小、术后恢复快、治疗效果与开放手术相当,甚至优于开放手术等优点,同时也是较大的复杂肾结石一线治疗方案,伴随着影像学的进步、碎石仪器的迅猛发展和腔内技术的提高,人们对结石的治疗观点有了新的拓展和认识,对这种手术方式提出新的要求以适应患者的需求,如何更加微创化,更能减少患者的痛苦及对患者的肾脏损伤最小成为目前泌尿外科工作人员研究的热点,现将近年来经皮肾镜取石术研究进展综述如下。  相似文献   
979.
目的:调查护理管理者领导力现状,并分析其影响因素。方法采用管理者实践量表、一般自我效能感量表、职业倦怠量表、角色认知量表对浙江省210名护理管理者进行问卷调查。结果共发放问卷210份,回收有效问卷182份,有效回收率为86.67%。本组护理管理者的领导力得分为(37.70±5.30)分;是否经常阅读管理书籍、是否参与护士长的分层培训、任命方式以及是否经过护士长岗前培训的护理管理者的领导力得分情况比较,差异有统计学意义(t值分别为-3.608,-7.136,2.343,-2.511;P<0.05)。领导力与角色认知中的角色模糊、自我效能感以及职业倦怠中的个人成就感均呈正相关,与角色认知中的角色冲突以及职业倦怠中的情绪枯竭、去人格化因子呈负相关( r值分别为0.589,0.521,0.509,-0.323,-0.291,-0.227;P<0.01)。多元线性回归分析显示,角色认知中的角色模糊因子、是否参加护士长分层培训、职业倦怠中的个人成就感因子、自我效能感和是否阅读管理书籍为领导力的影响因素(P<0.05)。结论领导力与护士长的角色认知、自我效能感、职业倦怠及是否分层培训均相关。管理者的分层培训有利于领导力的培养和提升,明确角色定位、降低职业倦怠和提高自我效能感同样可以提升护士长的领导力,另外护理管理者需加强经济管理学方面的知识培训。  相似文献   
980.
In vivo functional imaging at single-neuron resolution is an important approach to visualize biological processes in neuroscience. Light sheet microscopy (LSM) is a cutting edge in vivo imaging technique that provides micron-scale spatial resolution at high frame rate. Due to the scattering and absorption of tissue, however, conventional LSM is inadequate to resolve cells because of the attenuated signal to noise ratio (SNR). Using dual-beam illumination and confocal dual-slit detection, here a dual-slit confocal LSM is demonstrated to obtain the SNR enhanced images with frame rate twice as high as line confocal LSM method. Through theoretical calculations and experiments, the correlation between the slit’s width and SNR was determined to optimize the image quality. In vivo whole brain structural imaging stacks and the functional imaging sequences of single slice were obtained for analysis of calcium activities at single-cell resolution. A two-fold increase in imaging speed of conventional confocal LSM makes it possible to capture the sequence of the neurons’ activities and help reveal the potential functional connections in the whole zebrafish’s brain.OCIS codes: (180.2520) Fluorescence microscopy, (110.0110) Imaging systems, (170.3880) Medical and biological imaging, (170.2945) Illumination design, (180.1790) Confocal microscopy  相似文献   
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