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991.
中国新疆与哈萨克斯坦共和国生态环境特点极为相似,荒漠、半荒漠草地类型占草原面积的首位。由草原研究所派出的科技交流团,先后考察了哈国荒漠草地现状与改良利用情况,就优良旱生牧草新品种选育和荒漠、半荒漠区无灌溉条件下人工草地建植与管理技术模式达成技术合作事宜。 相似文献
992.
肝癌间质及癌旁病变的病理分析 总被引:2,自引:0,他引:2
目的 研究肝癌间质及癌旁病变的临床病理意义。方法 在 2 0例肝癌组织标本中取 45个癌结节 ,分别在癌结节中间、癌旁肝组织等部位取组织 4块 ,连续切片 ,显微镜下观察。结果 19个结节有完整窦内皮细胞围绕癌巢 ,其中癌结节肉眼小于3cm者 13个 ,大于 3cm者 6个。 2 6个癌结节无完整窦内皮细胞围绕癌巢 ,其中癌结节直径大于 3cm者 2 4个 ,小于 3cm者 2个。2 0例中有 13例合并肝硬化 ,17例有乙型肝炎病毒感染和HBsAg阳性。 结论 病理连续切片 ,显微镜下观察肝癌间质及癌旁病变是预测肝癌患者预后的重要病理学指标 相似文献
993.
Manuel Steiner Andishe Attarbaschi Margit K nig Helmut Gadner Oskar A. Haas Georg Mann 《Pediatric hematology and oncology》2004,22(1):11-16
Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposing factor. 相似文献
994.
Intraductal papillary mucinous tumor (IPMT) of the pancreas is characterized by slow growth and a relatively favorable prognosis, however, invasive cancer originating in an IPMT is associated with a poor prognosis. Although various parameters in imaging modalities have been advocated to differentiate between benign IPMN and malignant ones, it is not easy to obtain definite diagnosis based on these parameters. Peroral pancreatoscopy (POPS) allows a clear and direct visualization of the pancreatic duct, providing useful information regarding tumor nature in IPMT. The authors have studied the usefulness of POPS in the diagnosis of IPMT. Nevertheless, its usefulness is not necessarily widely accepted and the significance of POPS is still controversial. In this review, the authors intended to address the diagnostic value of POPS and to clarify its role in the diagnosis of IPMT. The authors think treatment of IPMT can be improved by introducing POPS because the determination of surgical procedure as well as the area of resection based on the preoperative diagnosis of the involvement of the main pancreatic duct and branch duct is inevitable. 相似文献
995.
996.
颈肩背轴型反流皮瓣修复儿童颏颈瘢痕挛缩 总被引:2,自引:1,他引:1
目的探讨修复儿童颏颈瘢痕挛缩一种实用而较理想的方法.方法以颈横动脉浅支为蒂,利用其与旋肩胛动脉皮支的丰富吻合,反流形成超长的轴型皮瓣,向前旋转修复瘢痕松解后的颈前创面.结果采用本皮瓣修复30例儿童颏颈瘢痕挛缩,其中18例随访2年,颈部活动自如,颌骨发育无明显异常,皮瓣色泽良好,效果令人满意.结论本皮瓣轴型血管恒定,反流灌注动脉压高有保证,供瓣面积充足,供区多可直接拉拢缝合,是修复儿童颏颈瘢痕挛缩的较理想方法. 相似文献
997.
Neuropsychological Findings: Myoclonic Astatic Epilepsy (MAE) and Lennox-Gastaut Syndrome (LGS) 总被引:1,自引:0,他引:1
Melissa Filippini Antonella Boni Gloria Dazzani Angelo Guerra Giuseppe Gobbi 《Epilepsia》2006,47(S2):56-59
Summary: Purpose: To identify a specific neuropsychological profile associated with myoclonic astatic epilepsy (MAE) and Lennox-Gastaut syndrome (LGS).
Methods: Seven patients diagnosed with MAE and four patients diagnosed with LGS were selected from patients referred to our Child Neurology Unit. The patients were assessed both clinically (awake, sleep, Holter EEG, seizures frequency, and semiology) and neuropsychologically (IQ, language, attention, visuospatial and visuomotor abilities, and behavior). One representative case of each syndrome is presented here.
Results: The clinical picture of the MAE patient resembled that of an MAE condition associated with transitory epileptic encephalopathy. The neuropsychological findings suggest that electroclinical anomalies can temporarily affect cognitive and behavioral functioning. Early effective antiepileptic drug (AED) treatment was found to improve cognitive outcome. In contrast, LGS was associated with mental retardation, which persisted after seizure control.
Conclusions: At present, it remains difficult to delineate a precise neuropsychological profile associated with MAE and LGS. The cognitive outcome of MAE is variable and depends on the clinical pattern. With regard to LGS, the hypothesis of a genetic predisposition underlying both the epilepsy and the mental retardation is still valid. Alternatively, exposure to subclinical electrophysiological anomalies during a critical period of cerebral development may be responsible for the mental retardation. At the time the clinical manifestations appear, drug treatment, even if effective, would have only limited impact on cognitive outcome. However, early multidisciplinary intervention may help to improve behavior and communicative abilities, enhancing the quality of life of these children and their families. 相似文献
Methods: Seven patients diagnosed with MAE and four patients diagnosed with LGS were selected from patients referred to our Child Neurology Unit. The patients were assessed both clinically (awake, sleep, Holter EEG, seizures frequency, and semiology) and neuropsychologically (IQ, language, attention, visuospatial and visuomotor abilities, and behavior). One representative case of each syndrome is presented here.
Results: The clinical picture of the MAE patient resembled that of an MAE condition associated with transitory epileptic encephalopathy. The neuropsychological findings suggest that electroclinical anomalies can temporarily affect cognitive and behavioral functioning. Early effective antiepileptic drug (AED) treatment was found to improve cognitive outcome. In contrast, LGS was associated with mental retardation, which persisted after seizure control.
Conclusions: At present, it remains difficult to delineate a precise neuropsychological profile associated with MAE and LGS. The cognitive outcome of MAE is variable and depends on the clinical pattern. With regard to LGS, the hypothesis of a genetic predisposition underlying both the epilepsy and the mental retardation is still valid. Alternatively, exposure to subclinical electrophysiological anomalies during a critical period of cerebral development may be responsible for the mental retardation. At the time the clinical manifestations appear, drug treatment, even if effective, would have only limited impact on cognitive outcome. However, early multidisciplinary intervention may help to improve behavior and communicative abilities, enhancing the quality of life of these children and their families. 相似文献
998.
皮质发育障碍模型的建立及其致痫敏感性的研究 总被引:1,自引:0,他引:1
目的:建立皮质发育障碍模型,探讨皮质发育障碍模型的敏感性。方法:在SD大鼠孕17d腹腔注入1,3-二氯乙烯-亚硝基脲(BCNU)制作皮质发育障碍模型;Nissl染色观察P60d仔鼠病理变化;选取P60d雄性仔鼠,腹腔注射氯化锂-毛果芸香碱,分别比较两组大鼠癫发生的潜伏期、持续状态时间和死亡率。结果:同龄仔鼠脑组织湿重实验组比对照组显著减轻(P<0.01);Nissl染色显示皮质变薄、皮质层次紊乱、海马区域异位细胞异常聚集;有皮质发育障碍的仔鼠注射氯化锂-毛果芸香碱后,癫发生的潜伏期显著缩短(P<0.01),癫持续状态时间延长(P<0.01),死亡率显著升高(P<0.05)。结论:BCNU致皮质发育障碍模型具有癫易感性。 相似文献
999.
Despite numerous studies of approach- and avoidant mindsets, relatively little research has addressed the impact of such motivational orientations on performance and emotion in a real-time, multi-task setting. A laboratory simulation is reported that examines the influence of an induced approach-centered, an avoidance-centered, and a “neutral” motivational mindset upon multiple aspects of task performance, self-regulatory cognition, and affect. Undergraduate females randomly assigned to one of three mindset conditions performed a simulated automobile drive across one practice and two experimental trials. Dependent measures included divided attention, behavioral indicators of driving “cautiousness” in relatively safe straight roadway sections as well as during more risk-filled driving, multiple aspects of self-regulatory thinking (including self-monitoring, intended effort, and self-administered consequences), and positive and negative affect. Results revealed that the avoidant mindset produced poorer executive attention (i.e., fewer correctly detected divided attention events), more “cautious” driving behavior and reduced performance variability (i.e., greater control) when driving on presumably safe, straight roadway sections, lower self-reports of intended effort, and greater negative affect relative to the approach mindset. Results are intepreted within a self-regulation-centered motivational framework. Implications of the multi-task simulation for the study of normal and disordered adjustment are considered. 相似文献
1000.
目的首先确定中毒药物,然后通过测定血药浓度以了解中毒程度,为重度苯妥英钠中毒患者临床抢救治疗提供依据。方法间隔一定时间采集患者静脉血,萃取血中药物,在211 nm处以反相高效液相色谱法定性,明确中毒药物并测定血药浓度。结果在苯妥英中毒患者中最高血药浓度为68.94 mg.L-1,接近治疗浓度上限的3.5倍。结论患者为重度中毒,危及生命,需临床药师与临床医师积极配合,施行全程药学监护。 相似文献