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111.
Ana Teresa Timóteo Andreia Mamede Maria de Lurdes Ferreira José Serra José Alberto Oliveira Rui Cruz Ferreira Jorge Quininha 《Revista portuguesa de cardiologia》2007,26(2):135-143
BACKGROUND: Nitrate therapy can induce ischemic preconditioning with a consequent increase in tolerance to ischemia. In the context of acute coronary syndromes (ACS), nitrates may result in a different presentation. with greater protection. OBJECTIVES: To investigate in a population of patients with ACS whether previous chronic use of nitrates results in a different presentation of ACS. METHODS: We studied 287 patients (65 +/- 13 years, 66% male) admitted to our department in the first six months of 2005 with ACS (with and without ST-segment elevation). Of these, 8% were under nitrate therapy at the time of admission. In this group, 27% presented ACS without ST-segment elevation, while in the group without nitrates this value was 58% (p = 0.005). By univariate analysis, the use of nitrates was a predictor of the preferential occurrence of non-ST-segment elevation ACS (OR 0.27, 95% CI 0.10-0.71). After correction for the potential influence of variables (age, gender, previous revascularization and smoking) by multivariate logistic regression, nitrate therapy remained a borderline predictor of clinical presentation as non-ST-segment elevation ACS (OR 0.37, 95% CI 0.13-1.04, p = 0.059). CONCLUSIONS: Previous use of nitrates was associated with a tendency to present as non-ST-segment elevation ACS. This finding may be explained by the hypothesis that nitrates induce pharmacological preconditioning, reducing the transmural extent of myocardial infarction. 相似文献
112.
Objective To compare the clinical efficacy of postoperative intraperitoneal chemotherapy combined with systemic chemotherapy to systemic chemotherapy alone for serosa-involved colorectal cancer. Methods According to the criteria of serosa-involving in colorectal cancer, 332 cases were divided into 2 groups prospectively without randomization. Study group (n=166) was treated with intraperitoneal chemotherapy combined with systemic chemotherapy, and control group (n=166) with systemic chemotherapy alone. Incidence of local recurrence, peritoneal metastasis, hepatic metastasis, other distant metastasis and 3-year, 5-year overall survival (OS) rate of two groups were compared. Results 3-year and 5-year OS rates of stage Ⅱ B in study group were similar to those in control group (χ2=0.612,P=0.434). The above rates of stage Ⅲ in study group were higher than those in control group (χ2=3.989,P=0.046). Either the study group or the control group, the 3-year and 5-year OS rates of patients undergone laparoscopic surgery or open surgery were similar (P=0.839, P=0.172). Incidences of local recurrence, peritoneal metastasis and hepatic metastasis in study group were 1.9%, 3.8% and 3.8% respetively, lower than those in control group (8.2%,9.5% and 10.1%,P<0.05). Distant metastasis rate in study group was similar to that in control group. In study group, intraperitoneal chemotherapy regimen with Oxaliplatin had lower rates of peritoneal metastasis and hepatic metastasis as compared to that with Cisplatin (0.9% vs 8.8% ,P=0.019), while the incidences of local recurrence and other distant metastasis were similar. Conclusions Postoperative intraperitoneal chemotherapy combined with systemic chemotherapy improves 3-year and 5-year overall survival rates in patients with stage Ⅲ serosa-involved colorectal cancer, and decreases local recurrence, peritoneal metastasis and liver metastasis rate, especially when intraperitoneal chemotherapy regimen contains Oxaliphtin. Comparing with open surgery, laparoscopic surgery dose not improve 3-year and S-year overall survival rates in patients receiving combined chemotherapy or systemic chemotherapy alone. 相似文献
113.
Post-injury regeneration in rat sciatic nerve facilitated by neurotrophic factors secreted by amniotic fluid mesenchymal stem cells. 总被引:1,自引:0,他引:1
Hung-Chuan Pan Fu-Chou Cheng Chun-Jung Chen Shu-Zhen Lai Chi-Wen Lee Dar-Yu Yang Ming-Hong Chang Shu-Peng Ho 《Journal of clinical neuroscience》2007,14(11):1089-1098
Amniotic fluid mesenchymal stem cells have the ability to secrete neurotrophic factors that are able to promote neuron survival in vitro. The purpose of this study was to evaluate the effects of neurotrophic factors secreted by rat amniotic fluid mesenchymal stem cells on regeneration of sciatic nerve after crush injury. Fifty Sprague-Dawley rats weighing 250-300 g were used. The left sciatic nerve was crushed with a vessel clamp. Rat amniotic fluid mesenchymal stem cells embedded in fibrin glue were delivered to the injured nerve. Enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry were used to detect neurotrophic factors secreted by the amniotic fluid mesenchymal stem cells. Nerve regeneration was assessed by motor function, electrophysiology, histology, and immunocytochemistry studies. Positive CD29/44, and negative CD11b/45, as well as high levels of expression of brain-derived neurotrophic factor, glia cell line-derived neurotrophic factor, ciliary neurotrophic factor (CNTF), nerve growth factor, and neurotrophin-3 (NT-3) were demonstrated in amniotic fluid mesenchymal stem cells. Motor function recovery, the compound muscle action potential, and nerve conduction latency showed significant improvement in rats treated with amniotic fluid mesenchymal stem cells. ELISA measurement in retrieved nerves displayed statistically significant elevation of CNTF and NT-3. The immunocytochemical studies demonstrated positive staining for NT-3 and CNTF in transplanted cells. The histology and immunocytochemistry studies revealed less fibrosis and a high level of expression of S-100 and glial fibrillary acid protein at the crush site. Rat amniotic fluid mesenchymal stem cells may facilitate regeneration in the sciatic nerve after crush injury. The increased nerve regeneration found in this study may be due to the neurotrophic factors secreted by amniotic fluid mesenchymal stem cells. 相似文献
114.
目的:研究中药生精冲剂对大鼠精索静脉曲张的影响及疗效。方法:从80只SD雄性大鼠中随机抽出20只作为假手术组,余60只均建立精索静脉曲张病理模型后随机均分为模型组、生精冲剂组和克罗米芬组。造模后15d生精冲剂组和克罗米酚组分别给予生精冲剂4g/(kg·d)和克罗米芬20mg/(kg·d)灌胃,模型组和假手术组正常喂食。造模后45d放免法测定血清性激素(FSH、LH和T)及观察各组大鼠睾丸组织结构。结果:生精冲剂组大鼠光镜下睾丸组织结构优于模型组和克罗米芬组;血清FSH、LH生精冲剂组显著低于模型组和克罗米芬组(P〈0.05),而克罗米芬组显著高于其他3组。T在生精冲剂组、克罗米芬组和假手术组之间无显著差异,但均显著高于模型组(P〈0.05)。结论:中药生精冲剂对精索静脉曲张引起的睾丸损害有保护及修复作用,且可能优于克罗米芬。 相似文献
115.
目的探讨胆汁返流与幽门区局部神经递质一氧化氮的变化对应激性溃疡发病的影响及可能的机理。方法采用冷束缚应激方法复制应激性溃疡的动物模型,将60只成年SD大鼠分为两部分,第1部分:对照组10只,溃疡组30只,用于观测影响应激性溃疡发生的相关因素;第2部分:左旋硝基精氨酸甲酯(L—NAME)预处理组10只(L—NAME组),生理盐水预处理组10只(生理盐水组),用于观测幽门区局部一氧化氮含量变化对其他因素的影响。分别检测各组胃内胆汁酸浓度、胃黏膜溃疡指数(Guth评分)以及胃内pH值,用生化试剂盒检测幽门区一氧化氮的含量。结果溃疡组应激结束后1h幽门区一氧化氮含量达到峰值(P〈0.01),应激结束后2h胃内胆汁酸浓度和pH值均达到峰值(P〈0.01),应激结束后4h胃内溃疡指数达到峰值(P〈0.01)。L-NAME组的胃内胆汁酸浓度、溃疡指数及一氧化氮含量较生理盐水组显著降低(P〈0.01,P〈0.05),而胃内pH值的差异无统计学意义(P〉0.05)。幽门区一氧化氮含量与胆汁酸浓度呈正相关(r=0.715,F=12.55,P=0.017)。结论幽门区一氧化氮含量变化与胆汁的返流量之间存在正相关关系,而L—NAME的幽门区局部干预使幽门区一氧化氮含量减少,幽门松弛程度降低,胆汁返流量也随之减少,进而降低溃疡指数,起到保护胃黏膜的作用。 相似文献
116.
Yanhong Li Shuanke Wang Yayi Xi Jing Wang Wenjie Pan Yingbin Shi Mige Wang 《中国神经再生研究》2007,2(8):471-474
BACKGROUND: At present, there is still lack of effective drugs for chronic spinal cord injury, whereas it is found recently that estrogen has a neuroprotective effect on brain and spinal cord injuries.
OBJECTIVE: To observe the effect of estrogen on the apoptosis of nerve cells after gradual chronic spinal cord injury in ovariectomized rats.
DESIGN: A randomized controlled animal trial.
SETTING: Institute of Orthopaedics, the Second Hospital of Lanzhou University.
MATERIALS: Sixty-five female Wistar rats of common degree, weighing 220–250 g, were provided by the experimental animal center of Lanzhou University. The rats were randomly divided into sham-operated group (n =5), estrogen-treated group (n =30) and saline control group (n =30), and the latter two groups were observed at 1, 3, 7, 14, 28 and 60 days respectively, and 5 rats for each time point.
METHODS: All the rats were treated with bilateral oophorectomy 2 weeks before the experiment. T10 vertebral lamina was revolved into using plastic screw. The spinal canal impingement was not induced initially. After that, the original incision was opened to expose the screw every 7–10 days.
MAIN OUTCOME MEASURES: The apoptosis and Caspase-3 positive cells in the damaged spinal cord were detected using terminal deoxynucleotidal transferase-mediated dUTP-biotin nick end labeling (TUNEL) method and Caspase-3 immunohistochemical staining at 1, 3, 7, 14, 28 and 60 days after chronic spinal cord injury respectively.
RESULTS: Totally 65 rats were used, and the deleted ones during the experiment were supplemented by others. Changes of Caspase-3 expression after spinal cord injury: In the sham-operated group, only a small amount of Caspase-3 proteins were observed in the rat spinal cord, mainly located in motor neurons of spinal cord anterior horn. In the estrogen-treated group and saline control group, positive cells expressed occasionally at 1 day postoperatively, began to increase obviously at 7 days after injury, strongly expressed at 14 and 28 days, but decreased at 60 days, mainly located in the neurons of spinal cord gray matter anterior horn, and they expressed fewer in the motor neurons and white matter of ventral horn, and there were obvious differences between the estrogen-treated group and saline control group at 7, 14, 28 and 60 days (P < 0.05).
CONCLUSION: Estrogen can reduce the apoptosis of nerve cells and promote the recovery of neurological function following gradual chronic spinal cord injury. 相似文献
117.
Garth Bissette Violetta Klimek Jun Pan Craig Stockmeier Gregory Ordway 《Neuropsychopharmacology》2003,28(7):1328-1335
Research evidence that corticotropin-releasing factor (CRF) plays a role in the pathophysiology of major depressive disorder (MDD) has accumulated over the past 20 years. The elevation of lumbar cerebrospinal fluid (CSF) concentrations of CRF decreased responsiveness of pituitary CRF receptors to challenge with synthetic CRF, and increased levels of serum cortisol in MDD subjects support the hypothesis that CRF is chronically hypersecreted in at least the endocrine circuits of the hypothalamic-pituitary-adrenal (HPA) axis and may also involve other CRF brain circuits mediating emotional responses and/or arousal. One such circuit includes the excitatory CRF input to the locus coeruleus (LC), the major source of norepinephrine in the brain. Furthermore, there are now reports of decreased levels of CRF in lumbar CSF from MDD patients after symptom relief from chronic treatment with antidepressant drugs or electroconvulsive therapy. Whether this normalization reflects therapeutic effects on both endocrine- and limbic-associated CRF circuits has not yet been effectively addressed. In this brief report, we describe increased concentrations of CRF-like immunoreactivity in micropunches of post-mortem LC from subjects with MDD symptoms as established by retrospective psychiatric diagnosis compared to nondepressed subjects matched for age and sex. 相似文献
118.
Opticatrophy,acommondiseasewhichleadstoblindness,respondstofewtreatment.However,acupuncturehasbeenactuallyusedandtheclinicaleffectintreatingthisconditionisratherpreferable.Byusingtheacupunctureformula"Three--EyeNeedling",remarkableclinicaloutcomeisachievedandtheresultoftherelatedelectrophysiologicalparametersfollowingtheacupuncturepracticeintreatingopticatrophyhasbeenobserved.METHODSClinicalD8tsTheclinicalmaterialswerecollectedintheSpecialClinicofOpticAtrophyoftheDepartmentofAcupuncture… 相似文献
119.
120.
本文对夹竹桃甙抑制Na~+、K~+-ATP酶的动力学作了探讨,并与乌本甙的作用进行了比较。结果表明:夹竹桃甙抑制Na~+、K~+-ATP酶,在Na~+、K~+浓度改变对均为非竞争性抑制,Na~+/K~+比例6:1时,为混合性抑制,而ATP对夹竹桃甙的作用几无影响。 相似文献