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81.
Agitated behavior is frequently associated with traumatic closed head injury. Proactive behavioral intervention is often not successful, and psychopharmacologic agents may result in increasing the targeted behavior through sedation. We describe a 32-year-old woman who developed severe agitation after frontal lobe closed head injury. After failing conservative behavioral management, a therapeutic trial of amitriptyline was initiated. Within two weeks, aggressive outbursts nearly ceased and attention span improved. Serial neuropsychologic assessment before and during amitriptyline therapy documented preservation of cognitive indices along with improvement in Trailmaking tasks. This case suggests that a trial of amitriptyline or other tricyclic antidepressant may be helpful in diminishing agitation associated with frontal lobe damage without impeding cognitive recovery.  相似文献   
82.
目的:为保护濒死心肌提供机会窗口,对比观察经冠脉移植自体骨髓单个核细胞或间充质干细胞后,实验性急性心肌梗死动物心功能变化及心肌组织核转录因子кB、心肌细胞凋亡情况。方法:实验于2005-03/2006-11在河北省人民医院实验中心完成。选用24只雄性冀中白猪,随机数字表法分为4组:正常对照组、模型组、单个核细胞组、间充质干细胞组,6只/组。①24只猪均以盐酸氯胺酮200mg臀部肌肉注射麻醉后,分别于各自右侧股骨抽取骨髓20mL,采用Fercoll法分离获得骨髓单个核细胞,加入胶体金溶液,培养12~16h待用。分离过程中取出含有骨髓单个核细胞成分的细胞层,常规培养传代,每3d换液1次,贴壁生长细胞即为骨髓间充质干细胞,加入胶体金溶液,培养24h待用。②除正常对照组外,其余各组均经导管球囊封闭第一对角支以远的前降支,复制猪急性心肌梗死模型。单个核细胞组、间充质干细胞组均于造模后立即开通前降支,分别经球囊注入预先分离的骨髓单个核细胞6×108个、间充质干细胞6×108个。模型组造模后于梗死1h开通前降支,经球囊注入磷酸盐缓冲液10mL。③各组分别于术前及术后4周经心脏超声检测心功能,取材行病理学检查、心肌组织核转录因子кB的免疫组织化学检测及心肌细胞凋亡检测。结果:24只雄性白猪均进入结果分析。①心功能变化:术前各组左心室收缩末内径、左心室舒张末内径、左心室射血分数、短轴缩短率基本相似。移植术后4周,正常对照组、单个核细胞组、间充质干细胞组左心室舒张末内径均明显低于模型组(F=4.68,P=0.01),左心室射血分数及短轴缩短率均明显高于模型组(F=5.14,P=0.01;F=3.32,P=0.04),各组左心室收缩末内径差异无显著性意义(F=1.64,P=0.21)。②心肌组织病理学改变:电镜下单个核细胞组、间充质干细胞组在梗死边缘区可见有胶体金颗粒的不成熟的心肌细胞,胞质中散在肌丝结构,肌丝排列紊乱不规则。③心肌组织核转录因子кB阳性率表达:与模型组比较,单个核细胞组、间充质干细胞组的梗死边缘区核转录因子кB阳性率明显降低(F=25.59,P=0.0001);正常心肌区核转录因子кB阳性率亦明显降低(F=18.20,P=0.0001)。④心肌细胞凋亡检测结果:与模型组比较,单个核细胞组、间充质干细胞组在心肌梗死区细胞凋亡率均明显降低(F=6.63,P=0.0027),梗死边缘区细胞凋亡率亦明显降低(F=36.07,P=0.0001)。正常心肌区单个核细胞组细胞凋亡率与模型组基本相似(F=9.69,P=0.004),但间充质干细胞组有所降低。⑤心功能与心肌细胞凋亡及心肌组织NF-кB的相关性:急性心肌梗死4周时,左心室射血分数与心肌细胞凋亡、心肌组织核转录因子кB均呈负相关(r=0.613,P=0.001;r=-0.437,P=0.033)。心肌细胞凋亡与心肌组织核转录因子кB呈正相关(r=0.672,P=0.002)。结论:经冠脉移植骨髓单个核细胞和间充质干细胞均可改善实验性急性心肌梗死动物的心功能,与梗死边缘区核转录因子кB表达降低及心肌细胞凋亡减少有关。骨髓单个核细胞移植的促血管增生作用优于间充质干细胞移植。  相似文献   
83.
Multiple sclerosis (MS) is a neurological disease characterized by lesion-induced white matter deterioration. Brain atrophy and damage to normal appearing white matter (NAWM) and normal appearing gray matter (NAGM) have also been identified as consequences of MS. Neuroimaging has played an integral role in investigating the effects of white and gray matter damage across the three primary clinical phenotypes of the disease—primary progressive (PPMS), relapsing remitting (RRMS), and secondary progressive (SPMS) MS. Both conventional (e.g., T1-weighted imaged) and nonconventional (e.g., diffusion tensor imaging) neuroimaging methods have yielded important information regarding the structural integrity of the brain during the course of the disease. Moreover, it has provided the opportunity to explore the relationship between structural brain indices and cognitive functioning, such as executive functioning, in MS. In this paper, we provide a brief overview of executive functioning in MS, a general review of how structural damage presents in MS by way of sclerotic lesions, atrophy, and microstructural white matter damage, and, finally, how structural brain damage relates to executive dysfunction.  相似文献   
84.
Application of biosafety principles in blood establishments   总被引:1,自引:0,他引:1  
In light of increasing public and employee concern over potential infectious hazards associated with blood and other body fluids, several government agencies (the Food and Drug Administration, the Centers for Disease Control, the Occupational Safety and Health Administration, the Environmental Protection Agency, the Health Care Financing Administration and the National Heart, Lung and Blood Institute) cosponsored a Biosafety Workshop in April 1988. The objective of the workshop was to identify appropriate biosafety practices and standard control procedures to protect workers involved in the collection, storage, and transportation of human blood donations with the least possible disruption of the nation's blood supply. Speakers focused on human immunodeficiency virus (HIV) and hepatitis B virus (HBV); however, the safety principles discussed were considered equally applicable to other known (e.g., non-A, non-B hepatitis and human T-lymphotropic virus type I (HTLV-1) blood-transmitted infections. The resulting consensus included the need for blood establishments to develop and apply thoughtful biosafety programs to address staff training, accident prevention, HBV vaccination, handling spills, managing contaminated waste and transporting blood specimens. There was lack of agreement, however, on the usefulness of gloves during the phlebotomy of healthy blood donors.  相似文献   
85.
Cancers that grow in bone, such as myeloma and breast cancer metastases, cause devastating osteolytic bone destruction. These cancers hijack bone remodeling by stimulating osteoclastic bone resorption and suppressing bone formation. Currently, treatment is targeted primarily at blocking bone resorption, but this approach has achieved only limited success. Stimulating osteoblastic bone formation to promote repair is a novel alternative approach. We show that a soluble activin receptor type IIA fusion protein (ActRIIA.muFc) stimulates osteoblastogenesis (p < .01), promotes bone formation (p < .01) and increases bone mass in vivo (p < .001). We show that the development of osteolytic bone lesions in mice bearing murine myeloma cells is caused by both increased resorption (p < .05) and suppression of bone formation (p < .01). ActRIIA.muFc treatment stimulates osteoblastogenesis (p < .01), prevents myeloma‐induced suppression of bone formation (p < .05), blocks the development of osteolytic bone lesions (p < .05), and increases survival (p < .05). We also show, in a murine model of breast cancer bone metastasis, that ActRIIA.muFc again prevents bone destruction (p < .001) and inhibits bone metastases (p < .05). These findings show that stimulating osteoblastic bone formation with ActRIIA.muFc blocks the formation of osteolytic bone lesions and bone metastases in models of myeloma and breast cancer and paves the way for new approaches to treating this debilitating aspect of cancer. © 2010 American Society for Bone and Mineral Research.  相似文献   
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89.
OBJECTIVE: To identify genetic associations between allograft inflammatory factor 1 (AIF1) and systemic sclerosis (SSc), or its subsets, using a single nucleotide polymorphism (SNP) in a replicate case-control study. METHODS: The frequencies of alleles and genotypes of an SNP, rs2269475, for the AIF1 gene were examined in two large independent cohorts of SSc patients (n = 1015 total), and compared with two groups of normal controls (n = 893 total). Both cases and controls were stratified by ethnicity (Caucasian, African American and Hispanic) and by autoantibody status [anti-centromere antibodies (ACA) and anti-topoisomerase I antibody (ATA)]. RESULTS: The minor T allele and CT/TT genotype frequencies of the AIF1 SNP were not observed more frequently in SSc patients of the three ethnic groups (individually or combined) when compared with controls. On the other hand, T and CT/TT frequencies were significantly increased in ACA-positive Caucasian SSc patients, and all ACA-positive SSc patients (the three ethnic groups combined), when compared with ACA-negative SSc patients and with normal controls, with odds ratios of approximately 1.5. CONCLUSION: The data demonstrate a genetic association between AIF1 and the ACA-positive subset of SSc. This polymorphism is a non-synonymous substitution and therefore likely to represent an important functional change in AIF1. Since vascular pathology is a prominent feature in ACA-positive SSc patients, the observed association with a vasculotrophic inflammatory gene is biologically plausible and warrants further research.  相似文献   
90.
Echocardiographic measures of cardiac target organ damage, including left ventricular mass and relative wall thickness, are powerful predictors of heart disease morbidity and mortality. The aim of this study is to investigate whether single nucleotide polymorphisms in candidate genes for hypertension and heart disease have effects on quantitative measures of hypertensive cardiac target organ damage, independent of their actions on blood pressure levels, in a cohort of hypertensive black sibships. To detect replication of genetic effects across samples, this study took advantage of the affected sibling pair design and created 2 samples, each with 448 unrelated individuals. As part of the Genetic Epidemiology Network of Arteriopathy Study, subjects were screened using 2D echocardiography, and 395 single nucleotide polymorphisms in 80 candidate genes were genotyped. Linear regression was used to test for single nucleotide polymorphisms significantly associated with left ventricular mass index (g/m(2.7)) or relative wall thickness after adjusting for associated covariates. Significant single nucleotide polymorphisms were subsequently tested for consistent directionality in genotype-phenotype relationships across samples. Three single nucleotide polymorphisms, 1 each in the APOE, SCN7A, and SLC20A1 genes, were significantly associated in both samples with left ventricular mass index and had replicate genotype-phenotype relationships. One in the ADRB1 gene was significantly associated with relative wall thickness with replicate effects in both samples. We identified genetic variation that significantly influences left ventricular traits with replicable effects in a cohort of hypertensive, black siblings.  相似文献   
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