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991.
白质病变与血管性认知障碍的相关研究   总被引:1,自引:0,他引:1  
目的探讨白质病变与血管性认知障碍及其相关危险因素的关系,为血管性痴呆的预防、早期诊断和治疗提供理论依据。方法选择130例经影像学证实的白质病变患者,经简易智能状态检查量表(MMSE)评估分为认知障碍组和无认知障碍组,分别对白质病变部位和分级进行比较。结果室周病变、室周合并深部白质及弥漫性白质病变与认知障碍相关。结论白质病变对血管性认知障碍的发生有显著影响。  相似文献   
992.
Serum chemistry analyses represents a fundamental tool for the diagnosis and understanding of diseases in marine mammals. Although several studies are being conducted within the field of clinical pathology, haematological and serum chemistry data for Antillean manatees are deficient. The purpose of this study was to determine serum chemistry values for captive Antillean manatees within the CMA/Ibama facility in Brazil. Serum samples were obtained from five captive adult Antillean manatees fed with seagrass and analysed for aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, urea, creatinine, glucose, triglycerides, cholesterol, total protein, albumin, globulin, phosphate, chloride, calcium and uric acid. Blood chemistry parameters were determined using a semi‐automatic analyzer. Maximum, minimum, mean and standard deviations were calculated for each serum chemistry parameter. Differences on the values of males and females were verified using an unpaired Student's t‐test. All the parameters analysed were similar between sexes, with exception of AP, which was higher in females (191.43 ± 31.86 U/l). Alanine aminotransferase and uric acid values for Trichechus manatus manatus are reported for the first time in this paper. This study is the first to report serum chemistry parameter values for long‐term captive male and female Antillean manatees. Therefore, the lower values of albumin, phosphate, chloride, cholesterol and triglycerides obtained here highlight the importance of clinical pathology during health monitoring of captive marine mammals.  相似文献   
993.
目的分析影响肝癌肝移植术后生存率和无瘤生存率的危险因素,探讨国内肝移植治疗肝癌的选择标准。方法对67例接受同种异位原位肝移植治疗的原发性肝癌病人的基本资料和肿瘤相关资料包括术前病情分级、血清AFP水平、术前辅助治疗以及肝癌大小、数目、pTNM分期、肿瘤恶性程度分级等因素进行单因素和多因素分析。结果术后1年、2年累积生存率为77%、67%,6个月和12个月无瘤生存率为66%和58%。单因素分析显示对肝癌肝移植术后累积生存率影响有统计学意义的因素为CHILD分级(MELD积分)和肝外大血管侵犯;多因素分析影响肝癌肝移植术后无瘤生存率有统计学义的因素是肿瘤大小、大血管侵犯和肿瘤分化程度。结论影响肝癌肝移植术后生存率的因素仍是术前患者肝功能状态。对存在大血管侵犯的肝癌患者需严格控制肝移植术适应证,而无血管侵犯的患者在选择肝移植治疗时肿瘤大小指标可较米兰标准适当放宽。  相似文献   
994.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age.  相似文献   
995.
BACKGROUND AND PURPOSE: There are limited data on the pattern of cancer distribution among adolescents in Taiwan. This study evaluated the characteristics of these rare cancers in a medical center. METHODS: Analyses of the characteristics of malignant neoplasms for patients aged 14 to 17 years at diagnosis were performed for all cases recorded in the tumor registry of Chang Gung Memorial Hospital (CGMH) at Linkou for the period 1995 to 2001. All eligible tumors were categorized in 1 of 12 diagnostic groups according to the scheme of the International Classification of Childhood Cancer (ICCC). Relative frequencies, age, and gender variations and the characteristics of tumor types were analyzed. RESULTS: Cancer was diagnosed in 320 adolescents during the study period. The male/female ratio was 1.17. Leukemia was the leading diagnostic group. The frequency of carcinomas increased with age and was highest among 17-year-olds. In this age group, non-rhabdomyosarcoma soft tissue sarcoma/primitive neuroectodermal tumor (non-RMS STS/PNET), thyroid carcinoma (CA) and ovarian germ cell tumor (GCT) were the 3 most common solid tumors; the embryonal malignancies were rare. Tumors with the greatest male predominance were intracranial GCT (91%), nasopharyngeal CA (87.5%), osteosarcoma (84.6%), and colorectal CA (75%). Tumors with the greatest female predominance were thyroid CA (78.3%), gonadal GCT (75%), and non-RMS/PNET (56.5%). Hepatocellular CA comprised 9.4% of all carcinomas. CONCLUSIONS: The relative frequency and the distribution of histology subtypes among adolescents were between those of childhood and adult cancers. There were marked variations in tumor occurrence between genders and among different ages.  相似文献   
996.
997.
肢体抖动短暂性脑缺血发作(LS-TIA)的临床及影像   总被引:1,自引:1,他引:0  
目的 肢体抖动短暂性脑缺血发作(LS-TIA)临床少见,本文旨在提高临床医师对这一症候的认识.方法 总结北京协和医院诊断为肢体抖动短暂性脑缺血发作患者7例,行颈部血管超声、脑电图、头部核磁共振、经颅多普勒超声、核磁血管成像,4例行数字减影血管造影,2例行CT灌注成像检查.结果 均表现为发作性短暂不能控制的抖动,5例发作有明显诱因.全部患者均有抖动肢体对侧至少1条以上颅内和/或颅外动脉重度狭窄或闭塞.头部核磁共振4例显示抖动肢体对侧内分水岭脑梗死.脑电图均未见痫样放电,6例可见病变血管同侧额颞部慢波灶.经扩容和抗血小板聚集或者血管内支架治疗后,所有患者病情稳定.结论 肢体抖动短暂性脑缺血发作通常提示大血管严重的狭窄或闭塞,低灌注是其最可能的发病机制.  相似文献   
998.
目的 根据大白鼠皮肤碱烧伤创面早期病理组织学观察复制Ⅱ、Ⅲ度碱烧伤模型,研究碱烧伤的临床治疗.方法 Wistar纯种健康大白鼠20只,以不同浓度2mol/l、2.5mol/l、5mol/lNaOH,作用时间分别为30秒、45秒、60秒、75秒,涂抹于脱毛后的表皮.结果 2mol/L(60s)、2.5mol/L(45s),5mol/L(30s)即可直接造成Ⅱ度~深Ⅱ度烧伤;2mol/L(75s)、2.5mol/L(60s)、5 mol/L(45s)即可造成Ⅲ度烧伤,其烧伤深度与NaOH溶液浓度和作用时间呈正比.结论 Ⅱ度、Ⅲ度碱烧伤均为渐进性烧伤,与文献中介绍的潜拙样损伤似乎不同.另外,不同浓度NaOH溶液在相同时间对皮肤组织的损伤及同一浓度NaOH溶液在不同时间对大白鼠皮肤的损伤病理学变化均有差异.  相似文献   
999.
During the past decade, RGD-peptides have become a popular tool for the targeting of drugs and imaging agents to alphavbeta3-integrin expressing tumour vasculature. RGD-peptides have been introduced by recombinant means into therapeutic proteins and viruses. Chemical means have been applied to couple RGD-peptides and RGD-mimetics to liposomes, polymers, peptides, small molecule drugs and radiotracers. Some of these products show impressive results in preclinical animal models and a RGD targeted radiotracer has already successfully been tested in humans for the visualization of alphavbeta3-integrin, which demonstrates the feasibility of this approach. This review will summarize the structural requirements for RGD-peptides and RGD-mimetics as ligands for alphavbeta3. We will show how they have been introduced in the various types of constructs by chemical and recombinant techniques. The importance of multivalent RGD-constructs for high affinity binding and internalization will be highlighted. Furthermore the in vitro and in vivo efficacy of RGD-targeted therapeutics and diagnostics reported in recent years will be reviewed.  相似文献   
1000.
MED术中应用自制器械处理后纵韧带钙化及骨赘增生   总被引:1,自引:0,他引:1  
目的探讨脊柱后路显微内镜(microendoscopic disectomy,MED)手术治疗腰椎间盘突出症合并后纵韧带钙化及椎体后缘骨赘增生的方法. 方法 MED手术中应用自制弧形纤维环刀和L形打入器治疗115例该类患者. 结果全组随访12~30个月,平均22个月,按MacNab标准:优、良109例,可5例,差1例,优良率94.8(109/115).未出现硬脊膜破裂及神经孙上,未发生椎间隙感染,无中转开放手术. 结论正确运用MED技术,配合采用自制器械及相应的改良方法,能较好地处理合并后纵韧带钙化及椎体后缘骨赘增生的难题,进一步扩大了手术适应证范围,提高了疗效及安全性.  相似文献   
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