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71.
Atrial natriuretic peptide infusion and nitric oxide inhalation in patients with acute respiratory distress syndrome 总被引:1,自引:0,他引:1
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Bindels AJ van der Hoeven JG Groeneveld PH Frölich M Meinders AE 《Critical care (London, England)》2001,5(3):151-157
Aim
To study the effects of infusion of atrial natriuretic peptide (ANP) versus the inhalation of nitric oxide (NO) in patients with an early acute respiratory distress syndrome (ARDS). 相似文献72.
福建省高校贫困大学生心理健康水平与人格特征 总被引:1,自引:0,他引:1
目的:了解贫困生的心理健康现状和人格特征。方法:于2005-09/11随机抽取福州大学、福建师范大学、福建农林大学、福建中医学院、闽江学院2002-2004级学生2400名。男1478名,女922名,平均(20±1)岁。根据2004-11-04福建省福州市政府办公厅正式下发的《福州市人民政府关于提高城区城镇及农村居民最低生活保障标准的通知》中的规定,即城镇多人户每人每个月210元、单人户230元;农村多人户每人每月155元、单人户175元,本文把家庭人均月收入较少,有一定数额债务,只能缴纳部分学杂费,基本生活费接近于当地居民最低生活保障线(如上规定,本文以230元为基准)的学生定为“贫困生”。采用精神症状自评量表和16种人格因素问卷对高校贫困生的心理健康和人格特征进行调查。结果:发放问卷2400份,收回有效问卷2111份。其中贫困生539份。①贫困生精神症状自评量表的躯体化、强迫、人际敏感、抑郁、焦虑、敌对、恐怖、偏执、精神病性、其他、总症状指数得分均高于非贫困生(贫困生:1.61±0.56,2.02±0.64,1.92±0.63,1.71±0.56,1.65±0.58,1.73±0.68,1.57±0.62,1.81±0.65,1.67±0.54,1.76±0.63,1.74±0.49;非贫困生:1.48±0.45,1.89±0.56,1.79±0.57,1.61±0.51,1.54±0.50,1.61±0.56,1.44±0.49,1.66±0.54,1.54±0.46,1.61±0.53,1.62±0.41,P<0.01)。男女贫困生之间各因子分差异均不显著(P>0.05)。②福建省高校贫困大学生的心理问题检出率为24.5%,其中轻度心理问题(2≤因子分<3)为22.6%;中度心理问题(3≤因子分<4)为1.7%;重度心理问题(4≤因子分<5)为0.2%。心理问题以强迫、人际敏感、偏执、忧郁、敌对、焦虑等心理问题最为突出。③16种人格因素问卷中,贫困生乐群性、聪慧性、兴奋性、敏感性、怀疑性上得分低于非贫困生,有恒性、忧虑性、独立性得分高于非贫困生(贫困生:5.20±1.77,4.70±1.93,5.49±1.87,6.46±1.79,4.29±1.71,4.60±1.63,6.64±1.82,5.07±1.82;非贫困生:5.39±1.74,4.95±1.99,5.82±1.91,6.66±1.75,4.55±1.77,4.36±1.69,6.43±1.94,4.89±1.77,P<0.05~0.01)。④影响贫困生心理健康水平的主要人格因素按其影响作用从大到小有怀疑性、忧虑性、稳定性、兴奋性、自律性。结论:福建省高校贫困大学生的心理健康状况令人担忧,其人格特征对心理健康水平有重要影响。 相似文献
73.
目的:观察胸腰段椎弓根CT测量在椎弓根螺钉内固定中的作用,寻找一种个体化椎弓根螺钉置入的方法。方法:选择1999-02/2006-03河北工程大学附属医院收治的T12和/或L1段骨折患者59例,行螺旋CT检查及图像三维重建,重建结束后,得到胸腰段标本的三维图像,通过旋转和切割进行图像处理并测量,模拟出T11~L2的椎弓根形态,根据CT测量椎弓根的实际投照点进行调整,即横断面上椎弓根轴线与矢状位上椎弓根轴线的交点,在确定进钉点时选择下关节突为参照物,选用合适直径的螺钉进行植钉,植入螺钉后,连接棒或板系统。结果:262个椎弓根行植钉术,242个完全在椎弓根内,仅有20个螺钉穿透椎弓根皮质。术后平均随访16.1个月,均无临床并发症的发生,Frankel平均增加1.4级。术后有2例患者出现断钉(3枚),1例患者出现断棒,所植入的螺钉与机体生物相容性好,无不良反应的发生。结论:利用三维CT测量的数据辅助,严格按照个体化的椎弓根的轴线方向植钉,在置钉时应考虑到螺钉本身直径的因素,可以提高植钉的成功率。 相似文献
74.
Fernando L GonçalesJr Camila A Moma Aline G Vigani Adriana FCF Angerami Eduardo SL Gonçales Raquel Tozzo Maria HP Pavan Neiva SL Gonçales 《BMC infectious diseases》2010,10(1):212
Background
More than 50% of hepatitis C viruses (HCV)-infected patients do not respond to the classical Interferon (IFN)/Ribavirin (RBV) combination therapy. The aim of this study was to evaluate the efficacy of retreatment with Peg-Interferon alpha-2b (PEG-IFN alpha-2b) plus RBV, in patients with HCV, genotypes 1 or 3, who were non-responders to the previous standard treatment with IFN/RBV. 相似文献75.
76.
SM Vieira HP Lemos R Grespan MH Napimoga D Dal-Secco A Freitas TM Cunha WA Verri Jr DA Souza-Junior MC Jamur KS Fernandes C Oliver JS Silva MM Teixeira FQ Cunha 《British journal of pharmacology》2009,158(3):779-789
Background and purpose:
Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice.Experimental approach:
Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-α. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy.Key results:
Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-α, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-α antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-α production, which were inhibited by reparixin or anti-TNF-α treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-α upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-α or anti-LIX/CXCL5.Conclusion and implications:
Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-α, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1. 相似文献77.
Dynamics of free intracellular Ca2+ during synaptic and spike activity of cricket tibial motoneurons
For all nervous systems, motoneurons are the main output pathway. They are involved in generating episodic motor activity as well as enduring motor rhythms. To determine whether changes in cytosolic Ca2+ correlate with motor performance, we studied the spatiotemporal dynamics, mode of entry and role of free intracellular Ca2+ in cricket (Gryllus bimaculatus) front leg tibial extensor and flexor motoneurons. Synaptic activation or intracellular depolarising current injection uniformly increased Ca2+ with the same dynamics throughout the primary and secondary branches of the dendritic tree of all motoneurons. Ca2+ rise times (mean τrise, 233–295 ms) were lower than decay times (mean τdecay, 1927–1965 ms), and resulted in a Ca2+ plateau during repetitive activation, such as during walking. The neurons therefore operate with a different Ca2+ level during walking than during episodic leg movements. Ca2+ enters the dendritic processes of motoneurons via a voltage‐activated mechanism. Entry is driven by subthreshold excitation, and is largely independent of the neurons’ spiking activity. To what extent ligand‐activated mechanisms of Ca2+ entry operate remains uncertain. We found no evidence for any prominent Ca2+‐activated secondary currents in these motoneurons. Excitatory postsynaptic potentials evoked by extracellular stimulation of descending neurons were unaffected by the level of free intracellular Ca2+. The activity of tibial motoneurons therefore appears to be only weakly dependent on the level of free intracellular Ca2+ in dendrites. This is different to what has been found for many other neurons studied, and may represent an essential prerequisite for insect motoneurons to support a wide range of both episodic and rhythmic motor sequences underlying behaviour. 相似文献
78.
Thoracoscopic anatomical lung resection in children 总被引:1,自引:0,他引:1
Fuchs J Kirschner HJ Warmann SW Schellinger K Baden W Szavay P 《Zentralblatt für Chirurgie》2007,132(3):247-250
There are only few pediatric surgical centers across the world with expertise for minimally invasive anatomical lung resections in children. Between September 2003 and September 2005, 67 children underwent thoracoscopic surgery at the Department of Pediatric Surgery, University Hospital of Tuebingen, Germany. In 19 of these cases a lung resection was carried out, 8 of them had an anatomical lung resection. All patients underwent general anesthesia without selective intubation for the procedure. Intrathoracic pressure with insufflation of carbon dioxide of 1.5 l / min was held at 3-5 mmHg. Two 5 mm ports for video and instruments and one 12 mm port for a stapling device were used. Resected lung specimens were removed from the thorax through an additional 2-3 cm long incision. A bronchoscopy was carried out during surgery in all patients. Median age at operation was 5.6 years (range 3 months-20 years). Median operation time was 150 minutes (range 94-250 min). Conversion to open surgery was performed in 3 cases. This was due to bleeding in one child, due to a stiff lung in another patient with cystic fibrosis and due to a vascular and bronchial malformation in a third child suffering from middle lobe syndrome. There were no postoperative complications. Our preliminary results show, that thoracoscopic lung resections in children can be performed without major complications and excellent cosmetic results. For the necessity of a conversion to open surgery possible reasons may be insufficient intrathoracic overview as well as congenital anomalies of the vascular and / or the bronchial tract. Co-morbidities such as rib-fusion, deformities of the thorax or scoliosis can be avoided using thoracoscopic procedures. 相似文献
79.
BACKGROUND AND DESIGN--The loose anagen hair syndrome is a recently described disorder with enhanced hair loss in which anagen hairs can be painlessly pulled from the scalp. RESULTS--In three families, we have observed an autosomal dominant form of inheritance. We have confirmed that the extracted bulbs consist only of cortical cells and that the hair shafts have an abnormal shape. Using routine light and electron microscopy, we observed disadhesion between all layers of the follicle and within some layers and premature keratinization of the inner root sheath of the follicle. In addition, abnormal maturation of the various layers was observed at the electron microscopic level, including regions of the cortex that contained decreased numbers of filaments. The disorder appears to be cyclic, since relatively normal and markedly affected regions of the shaft can be observed within a single follicle. CONCLUSIONS--Possible mechanisms responsible for the disease include abnormal intercellular signaling and disturbances of desmosomal components and/or cadherins. 相似文献
80.
Mutation hotspots due to sunlight in the p53 gene of nonmelanoma skin cancers. 总被引:20,自引:0,他引:20
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A Ziegler D J Leffell S Kunala H W Sharma M Gailani J A Simon A J Halperin H P Baden P E Shapiro A E Bale et al. 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(9):4216-4220
To identify the sites in the p53 tumor suppressor gene most susceptible to carcinogenic mutation by sunlight, the entire coding region of 27 basal cell carcinomas (BCCs) of the skin was sequenced. Fifty-six percent of tumors contained mutations, and these were UV-like: primarily CC-->TT or C-->T changes at dipyrimidine sites. Such mutations can alter more than half of the 393 amino acids in p53, but two-thirds occurred at nine sites at which mutations were seen more than once in BCC or in 27 previously studied squamous cell carcinomas of the skin. Seven of these mutation hotspots were specific to skin cancers. Internal-cancer hotspots not located at dipyrimidine sites were not mutated in skin cancers; moreover, UV photoproducts were absent at these nucleotides. The existence of hotspots altered the process of inactivating p53 in BCC compared to other cancers: allelic loss was rare, but 45% of the point mutations were accompanied by a second point mutation on the other allele. At least one of each pair was located at a hotspot. Sunlight, acting at mutation hotspots, appears to cause mutations so frequently that it is often responsible for two genetic events in BCC development. 相似文献