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991.
人脑是生物进化最高产物,人类智力以S型模式由低级向高级演变,故现代人处于智力进化的第二个缓慢发展阶段。人类的智商是有限的,但是人类认识自然、认识社会是无限的。提高人类智力应当在勤用脑,抗衰老,延年益寿上下功夫。 相似文献
992.
《Expert Review of Clinical Immunology》2013,9(11):1135-1149
A relevant fraction of HIV-1-infected individuals (ranging from 15 to 30%) presenting virologically successful highly active antiretroviral therapy fail to recover CD4 T-cell counts. These individuals, called immunodiscordant or immunological nonresponders, are at increased risk of clinical progression and death. Although older age, lower nadir CD4 T-cell count and HCV co-infection are some of clinical predictive factors, immunological mechanisms rely on impaired thymic production and accumulation of apoptosis-prone CD4 T cells. Indeed, immunodiscordant individuals may show increased tissue fibrosis and damage of gut-associated lymphoid tissue that results in higher hyperactivation, inflammation and immunosenescence, altered Treg/Th17 ratio and increased T-cell death. A better knowledge of the final pathogenic mechanism and factors influencing CD4 T-cell recovery will help to select the optimal therapeutic strategies for them. 相似文献
993.
Edmund Kenneth Kerut MD Philip G. Kogos MD Jason H. Anderson MD Michael Turner MD Robert Ascuitto MD Nancy Ross‐Ascuitto MD Sameh M. Said MD 《Echocardiography (Mount Kisco, N.Y.)》2018,35(7):1045-1048
A healthy 20‐year‐old male presented with aborted sudden death. Both thoracic echocardiography and cardiac computed tomographic angiography demonstrated the characteristic findings of ALCAPA noting a dilated and tortuous right coronary artery, dilated coronary collateral arteries within the interventricular septum or along the surface of the heart, and visualization of the left coronary artery origin from the posterior aspect of the main pulmonary artery. Both imaging modalities demonstrated all three characteristic findings of this rare coronary anomaly and served as complementary imaging studies for surgical correction. 相似文献
994.
脑组织柔软质脆,负责不同的功能区,血供丰富,因此,在脑科手术中吸引是非常重要的.吸引器头不能对脑组织造成接触性损伤,吸力大小必须适宜,大了可能吸走脑组织,小了出血吸不干净,影响视野,不利于手术的顺利进行.现介绍一种新型的吸引器头的制作与应用. 相似文献
995.
《The International journal of neuroscience》2012,122(9):1037-1046
The asymmetrical breakdown of the blood-brain barrier (BBB) was studied in female rats. Paw preference was assessed by a food reaching test. Adrenaline-induced hypertension was used to destroy the BBB, which was evaluated using triphenyltetrazolium (TTC) staining of the brain slices just after giving adrenaline for 30 s. In normal rats, the whole brain sections exhibited complete staining with TTC. After adrenaline infusion for 30 s, there were large unstained areas in the left brain in right-pawed animals, and vice versa in left-pawed animals. Similar results were obtained in seizure-induced breakdown of BBB. These results were explained by an asymmetric cerebral blood flow depending upon the paw preference in rats. It was suggested that this new method and the results are consistent with contralateral motor control that may be important in determining the dominant cerebral hemisphere in animals. 相似文献
996.
《Ultrastructural pathology》2013,37(2):90-98
Comparisons of atrial tissues from Syrian hamster offspring born from cocaine-treated mothers during the last days of pregnancy with sham-treated ones demonstrate irreversible focal ischemic damage in the Purkinje myofibers and minor endocardial damages as well as minute cardiomyocyte vacuolization. These defects are consistent with the pharmacotoxicity of cocaine or its metabolites. The damaged Purkinje myocytes apparently remain in contact with adjacent cardiomyocytes but undergo autolytic process similar to that found in autoschizic cell death. Adjacent cell type(s) appear to segregate or engulf the injured cells. Data collected in this report demonstrate why clinical bradyarrhythmias, arrhythmias, or sudden death as cardiac arrest can be found in pre- and postnatal cocaine-abused babies as well as those found in young individuals caused by acute or chronic cocaine abuse. 相似文献
997.
998.
《Journal of medical engineering & technology》2013,37(7-8):408-414
We tested a novel neurocatheter in a brain-tissue gel model of drug infusion via convection-enhanced delivery (CED) for the treatment of a variety of neurological diseases. CED is an alternative to systemic administration of agents by intravenous or oral routes, which are often less effective or carry risk of systemic side effects. We investigated two co-axial tube devices, with outer diameters of 1.6?mm and 2.0?mm. Bromophenol blue dye was infused into 400?ml of 0.6% agarose gel at 1?μl/min for 1?h, with/without the inner and outer tubes Luer-locked at the proximal end, with/without the inner tube primed, and with/without the inner tube preloaded into the outer tube upon insertion into the gel. The unlocked, primed, and unloaded configuration produced infusions that resulted in significantly less (p?<?0.05) entrapped air escaping into the gel and resulted in no reflux of infusate. 相似文献
999.
Md Asaduzzaman Khan Mohammad Mijanur Rahman Mousumi Tania Nusrat Fatima Shoshee Ai-hua Xu Han-chun Chen 《African journal of traditional, complementary, and alternative medicines》2013,10(3):436-441
The effects of Duranta repens fruits were investigated on H2O2 induced oxidative cell death to evaluate its antioxidative potential in vitro. HEK293T cells were treated with different concentrations [0–1000 µg/ ml] of ethanol extract (E-Ex) and methanol extract (M-Ex) of D. repens for 24h, and then treated with 100 µM H2O2 for 24h. Cell viability, antioxidant parameters of cells, and antioxidant constituents of the extracts were determined. Treatment with limited dose of E-Ex or M-Ex increased the survival rate of H2O2-treated HEK293T cells, however the extra-high dose showed growth inhibitory effect. Treatment with E-Ex or M-Ex protected cellular lipid per-oxidation. In vitro analyses showed the 2,2-diphenyl-1-picrylhydrazyl and H2O2 scavenging activities as well as reducing potential of the extracts. We report here that the limited dose of E-Ex and M-Ex possess antioxidative potential, which can protect H2O2-induced oxidative cell damage. 相似文献
1000.
心脏性猝死的相关危险因素 总被引:1,自引:0,他引:1
任兴备 《实用心脑肺血管病杂志》2011,19(1):137-138
目的 探讨心脏性猝死的相关危险因素,为预防心脏性猝死以及提高抢救成功率提供帮助。方法对我院2003-2009年收治的心脏性猝死患者69例的临床资料进行收集整理。结果经过临床推论和文献资料的查阅,证实在干预或消除其相关危险性因素后,心脏性猝死的发生率明显减少。结论心血管疾病的危险因素对心脏性猝死有直接影响,早期预防、避免诱发因素、及时处理是预防以及提高心脏性猝死抢救成功率的关键。 相似文献