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排序方式: 共有4209条查询结果,搜索用时 15 毫秒
41.
42.
Kazez A Demirbağ M Ustündağ B Ozercan IH Sağlam M 《Journal of pediatric surgery》2000,35(10):1444-1448
BACKGROUND/PURPOSE: The aim of this study was to determine the effect of melatonin, a hormone that is known as an antioxidant, on the prevention of tissue damage during mesenteric ischemia/reperfusion (I/R). METHODS: A total of 40 young Wistar-albino rats were divided equally into 4 groups with varied treatment. Group 1 was control (sham), group 2 was I/R, group 3 was I/R plus melatonin (10 mg/kg) and group 4 was I/R plus melatonin (20 mg/kg). I/R was realized as follows: after laparatomy, a microvascular atraumatic clip was placed across the superior mesenteric artery (SMA) under general anaesthesia, and it was removed after ischemia for 30 minutes. The first dose of melatonin was applied intraperitoneally at the start of reperfusion. The second and third doses were applied intramuscularly on the first and second day. Only SMA dissection under general anaesthesia was carried out in the control group rats. On the third day of the study all the rats were killed, and their bowels were removed. Malondialdehyde (MDA) levels were assayed as an index of lipid peroxidation reflecting free radical reaction in the intestine. Histopathologic analysis was made using light microscopy in a blind fashion. RESULTS: The levels of tissue MDA were found to be significantly lower in groups 3 and 4 compared with group 2 (P < .05). The MDA levels of group 4 did not differ significantly from that of the control group (P > .05). The histopathologic results were consistent with the MDA levels. CONCLUSION: These results suggest that melatonin has a strong antioxidant effect in preventing intestinal I/R damage, and that this effect is exerted in a dose-dependent manner. 相似文献
43.
Brahim Housni Rachida Bayad Rachid Cherkab Sa?d Salmi Mohamed Miguil 《Hypertension in pregnancy》2004,23(3):269-273
Diffuse neurological manifestations of preeclampsia are due to endothelial involvement that lead to ischemia, hemorrhage, or edema. We analyzed clinical and radiological features and the course of brainstem ischemic strokes in a preeclampsia patient. We report a case of severe preeclampsia in a 30-year-old woman who was admitted 10 hr after a vaginal delivery at home. The pregnancy was at 39 wk, with no prenatal care. At her admission, she was conscious, and she had tetraparesia, swinging deep tendon reflex testing, drowsiness, and dysarthria; the BP was at 160/100 mmHg and 4 + proteinuria; magnetic resonance imaging revealed brainstem ischemic stroke. The evolution was favorable with symptomatic treatment. The patient was discharged on the 16th day; 2 months later she had a normal recovery. Brainstem strokes are rare. They are frequently due to hemorrhage; sometimes, they can also be ischemic. Their course is favorable. 相似文献
44.
2004年新疆某中专学生HBsAg、抗-HBs的检测结果分析 总被引:3,自引:0,他引:3
目的为了解新疆中等专业学校新生乙型肝炎病毒感染状况和抗-HBs水平。方法采用整群抽样法,抽取558名入校新生用ELISA法检测乙肝表面抗原(HBsAg)与抗体(抗-HBs)。结果558名新生的HBsAg阳性率为8.42%,城市来源的学生HBaAg阳性率高于农村来源的学生,但是差异无统计学意义(P〉0.05)。抗-HBs阳性率为54.84%,城市来源的学生高于农村来源的学生,差异有统计学意义(P〈0.01)。乙肝病毒无免疫保护作用的占检测总人数36.74%,其中农村学生高于城市学生,差异有统计学意义(P〈0.01)。结论新生体检很有必要,对乙肝无免疫力的给予乙肝全程免疫,抗-HBs弱阳性的给予一次加强免疫。 相似文献
45.
Lleonart R Riego E Saínz de la Peña MV Bacallao K Amaro F Santiesteban M Blanco M Currenti H Puentes A Rolo F Herrera L de la Fuente J 《International journal of legal medicine》2000,113(2):98-101
We report the positive identification of several members of the guerrillas led by Ernesto “Che” Guevara on the 1960 s in
Bolivia by means of DNA fingerprinting. Successful DNA typing of both short tandem repeat loci and the hypervariable region
of the human mitochondrial DNA was achieved after extracting total DNA from bones obtained from two burial sites. Given the
size of the Cuban database for the STR allele frequencies, a conservative approach was followed to estimate the statistical
significance of the genetic evidence. The estimated probabilities of paternity for the two cases in which the paternity logic
was applied were higher than 99%. One case was analyzed using mitochondrial DNA and could not be excluded from the identity
proposed by the forensic anthropology team. A fourth case was identified by exclusion, on the basis of the positive identification
of the other remains, the historical and other anthropological evidence.
Received: 19 January 1999 / Received in revised form: 15 April 1999 相似文献
46.
Saïd Yous Valérie Wallez Mirabelle Belloir Daniel H. Caignard Christopher R. McCurdy Jacques H. Poupaert 《Medicinal chemistry research》2005,14(3):158-168
In an effort to produce a new pharmacological probe with high affinity and selectivity for the sigma-1 receptor, we have synthesized
a series of original 2(3H)-benzothiazolones utilizing compound 4 [3-(1-piperidinoethyl)-6-propylbenzothiazolin-2-one] as a lead. Receptor binding affinities were determined at sigma-1 and
sigma-2 receptors. The best ligand (9, sigma-1 Ki = 0.56 nM, selectivity ratio >1000) was obtained with an azepine side-chain. When tested on a wide battery of receptors,
including 5HT2A(h), 5HT3(h), α1, α 2, β1, β2, H1, H2, opioids, D1(h), D2(h), 5HT uptake, and DOPA uptake, compound 9 showed submicromolar affinity only for α2 (Ki = 205 nM) and H1 (Ki = 311 nM). 相似文献
47.
米氮平与舍曲林治疗抑郁症伴有焦虑疗效比较 总被引:9,自引:3,他引:9
目的 :比较米氮平与舍曲林对抑郁症伴焦虑的疗效及其安全性。方法 :1 1 1例抑郁症分为 2组。米氮平组 56例 [男性 30例 ,女性 2 6例 ,年龄(39±s 1 3)a,本次抑郁病期 (3± 5)mo]予米氮平30~ 45mg ,po,qd;舍曲林组 55例 [男性 2 9例 ,女性 2 6例 ,年龄 (40± 1 2 )a,本次抑郁症病期 (4± 4)mo]予舍曲林 50~ 1 0 0mg,po,qd;均 6wk为一个疗程。结果 :对抑郁症状的治疗 ,米氮平组显效率73 % ,舍曲林组显效率 67% ,疗效差异无显著意义(P >0 .0 5) ;对焦虑症状的治疗 ,米氮平组显效率79 % ,舍曲林组显效率 44 % ,疗效差异有显著意义(P <0 .0 5)。整体药物不良反应发生率 2组相当。结论 :米氮平与舍曲林是安全有效的治疗抑郁症的药物 ,但抗焦虑作用米氮平优于舍曲林 相似文献
48.
用血清药理学方法观察毛茛提取液对家兔主动脉平滑肌细胞内钙的影响 总被引:2,自引:0,他引:2
目的:观察毛茛提取液含药血清对培养家兔主动脉平滑肌细胞内游离钙浓度的影响.方法:体外培养家兔主动脉平滑肌细胞(VSMC),用荧光指示剂INDO-AM负载细胞,灌胃给予不同浓度药物,观察不同稀释浓度含药血清及不同时相药物血清对由NE诱导细胞内游离钙浓度([Ca2 ]i)增加的影响.结果:毛茛提取液各含药血清组均能降低由NE诱发的细胞内[Ca2 ]i的升高.结论:毛茛提取液含药血清能减少VSMC细胞内[Ca2 ]i. 相似文献
49.
目的初步探讨粪便自诱导分子-2(AI-2)监测新生儿坏死性小肠结肠炎(NEC)病情变化的价值。方法以2017年10月至2018年4月收治的12例NEC患儿为研究对象,并按照胎龄、日龄、生产方式、喂养方式、抗生素使用等选择12例与NEC组患儿匹配的非NEC新生儿为对照组。NEC诊断时定为急性期,再次开奶3天后定为恢复期。采集NEC急性期、恢复期和对照组的粪便标本,以BB170生物荧光检测法检测粪便AI-2浓度,采用16s rDNA高通量测序分析粪便菌群。结果在菌门水平,拟杆菌门比例在NEC组急性期、恢复期和对照组之间差异有统计学意义(P0.05),其中NEC恢复期比例最低。在菌属水平,肠球菌属、拟杆菌属比例在三组之间差异均有统计学意义(P0.05),其中NEC急性期肠球菌属比例最低,恢复期拟杆菌属比例最低。三组粪便AI-2浓度差异有统计学意义(P0.05),以NEC急性期为最低。结论 AI-2在监测NEC病情变化方面具有潜在临床应用价值。 相似文献
50.
Martina Lorenzetti Eva Pellicer Jordi Sort Maria Dolors Baró Janez Kova? Sa?a Novak Spomenka Kobe 《Materials》2014,7(1):180-194
The electrochemical behavior of polycrystalline TiO2 anatase coatings prepared by a one-step hydrothermal synthesis on commercially pure (CP) Ti grade 2 and a Ti13Nb13Zr alloy for bone implants was investigated in Hank’s solution at 37.5 °C. The aim was to verify to what extent the in-situ-grown anatase improved the behavior of the substrate in comparison to the bare substrates. Tafel-plot extrapolations from the potentiodynamic curves revealed a substantial improvement in the corrosion potentials for the anatase coatings. Moreover, the coatings grown on titanium also exhibited lower corrosion-current densities, indicating a longer survival of the implant. The results were explained by considering the effects of crystal morphology, coating thickness and porosity. Evidence for the existing porosity was obtained from corrosion and nano-indentation tests. The overall results indicated that the hydrothermally prepared anatase coatings, with the appropriate morphology and surface properties, have attractive prospects for use in medical devices, since better corrosion protection of the implant can be expected. 相似文献