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Schizencephaly: diagnosis and progression in utero   总被引:2,自引:0,他引:2  
Klingensmith  WC  d; Cioffi-Ragan  DT 《Radiology》1986,159(3):617-618
Schizencephaly is an unusual condition of obscure etiology. Most theories of pathogenesis postulate an in utero insult leading to maldevelopment rather than destruction of brain. The cause has most often been described as vascular or idiopathic dysgenesis. The authors report a case in which two in utero ultrasound (US) examinations performed at 31 and 36 menstrual weeks demonstrated progressive deterioration of the relatively narrow, symmetrical clefts connecting the lateral ventricles with the subarachnoid space into broad defects that corresponded to the entire distribution of the middle cerebral arteries. The findings in this case document progressive destruction of brain tissue in utero and are consistent with a vascular cause rather than a failure of formation of portions of the cerebral mantle.  相似文献   
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Background  

After the WHO issued the global alert for 2009 pandemic influenza A (H1N1), many national health agencies began to screen travelers on entry in airports, ports and border crossings to try to delay local transmission.  相似文献   
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We describe a patient with systemic lupus erythematosus (SLE)-like disease on immunosuppressive treatment who developed septic arthritis of the knee involving Legionella dumoffii. Cultures initially remained negative. A broad-range 16S PCR using synovial fluid revealed L. dumoffii rRNA genes, a finding that was subsequently confirmed by positive Legionella culture results.  相似文献   
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Breast cancer is one of the leading causes of cancer deaths among women[1].In the past 40 years,breast cancer incidence has doubled or even tripled in developed countries such as South Korea and Japan; whereas it is about 20% to 30% in China and India in the past decade[2-4]. An increasing incidence rate of 3%  相似文献   
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Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches.  相似文献   
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目的 探讨有关急危重病人血流动力学状态达到最佳化治疗研究中肺动脉导管 (Swan -Ganz)与复苏治疗的关系 ,评估生理、临床、治疗等方面因素对复苏治疗效果的影响。方法 从MEDLINE(英文医学文献资料网库 )中搜集所有与Swan -Ganz和血流动力学状态有关的 71篇研究文献。按照限定条件进行筛选 :①病人类型 :急性病 ,高危外科手术病人 ,创伤 ;②达到血流动力学指标正常值或超常值标准 ;③控制组死亡率 >2 0 % (危重组 )或 <15 % (一般组 ) ;④治疗后达到血流动力学指标的早晚 ;其中 2 1项研究接受Meta分析。结果 在危重组 ,早期达到血流动力学超常值治疗 ,2 1项研究中的 7项显示在控制组与治疗组之间死亡率有显著性的差别 (P <0 0 5 ) ;而晚期达到血流动力学超常值治疗的 6项研究 ,两组之间死亡率无显著性的差别 (P >0 0 5 )。在一般组 ,达到血流动力学正常值治疗的 5项研究和超常值治疗的 3项研究显示 ,控制组与治疗组之间死亡率无显著性的差别。结论 经Swan -Ganz引导早期达到血流动力学超常值治疗 ,能降低重病组的死亡率。  相似文献   
59.
Force-frequency curves of rabbit masseter motor units ( n=20) were determined, in order to study the capacity of these motor units for rate gradation and to establish the relationship between twitch contraction time (TCT) and the shape of the curves. Motor unit force responses were elicited by stimulating motoneurons in the trigeminal motor nucleus extracellularly. A sequence of pulse trains with increasing frequency rates was followed by trains with decreasing frequency rates. All motor units were classified as fast (F) units. The ascending force-frequency curves showed a distinct sigmoid appearance; the descending curves were shifted toward lower stimulation rates. The position and shape of the force-frequency curves related significantly to the TCT. The curves of slower units were located at lower frequencies and had a larger inclination. In addition, slower units had a lower fusion frequency and a larger twitch-tetanus ratio. Hence, slower units started to fuse and reached maximum force at lower stimulation rates than faster units and needed a smaller change in simulation frequency to achieve the same relative force. It can be concluded that the capacity for rate gradation differs between rabbit masseter motor units and that the TCT is a determinant for the position and shape of the force-frequency curves.  相似文献   
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