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101.
    
Background: Minimally invasive surgery is becoming increasingly popular in the field of pancreatic surgery. However, there are few studies of robotic distal pancreatectomy(RDP) for pancreatic ductal adenocarcinoma(PDAC). This study aimed to investigate the efficacy and feasibility of RDP for PDAC. Methods: Patients who underwent RDP or laparoscopic distal pancreatectomy(LDP) for PDAC between January 2015 and September 2020 were reviewed. Propensity score matching analyses were performed. Results...  相似文献   
102.
    
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients.  相似文献   
103.

Background  

We report baseline data on the organisation of COPD care in UK NHS hospitals participating in the National COPD Resources and Outcomes Project (NCROP).  相似文献   
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Clinical studies are evaluating possible advantages of allogeneic peripheral blood stem cell transplantation (PBSCT) over bone marrow transplantation (BMT). We compared immune reconstitution after PBSCT (n = 20) and BMT (n = 20) in terms of lymphocyte subset counts and proliferative in vitro responses to mitogens and recall antigens (follow-up: 5 to 11 months posttransplant). Additionally, 10 PBSC harvests and 10 marrow harvests were analyzed for their composition of immunocompetent cells. Compared with BMT patients, PBSCT recipients had PB counts of naive (CD4+CD45RA+) and memory (CD4+CD45RO+) helper T cells and of B cells (CD19+) that were elevated (P < .003, P < .001, and P < .004, respectively) and proliferative responses to phytohemagglutinin (P < .0001), pokeweed mitogen (P < .02), Tetanus toxoid (P < .0005), and Candida (P < .004) that were increased. PBSCT recipients received a mean of 188 (range, 44 to 280) x 10(6) naive helper T cells and 169 (range, 18 to 296) x 10(5) memory helper T cells per kilogram; the corresponding numbers for BMT recipients were 11 (range, 4 to 24) and 10 (range, 1 to 22) x 10(5) cells per kilogram, respectively. The question of whether the documented improved in vitro immune competence after PBSCT is associated with a lower incidence of infectious complications in vivo still needs further study.  相似文献   
106.
目的:构建雄激素受体基因第一外显子区CAG重复序列缺失的突变重组体,观察CAG重复序列的有,无对雄激素受体转录及表达的调控作用。方法:实验于2006—05/2007—05在解放军总医院老年医学研究所完成。按照重叠延伸反应的原理扩增CAG重复序列两端的基因片段,再将两片段混合,在加入一个引物的情况下进行8个PCR循环以有效完成重叠延伸,然后再加入另一引物进行22个循环,完成目的片段指数扩增,将目的片段克隆至真核表达载体PAR-IRES2-EGFP,转染HEK293细胞,采用Western blot法检测HEK293细胞雄激素受体蛋白。结果:构建的CAG重复序列缺失的突变重组体经酶切鉴定和DNA测序证实构建正确,转染真核细胞可检测到雄激素受体基因的表达。结论:重叠延伸PCR是进行体外基因拼接、体外缺失突变的简单、快速的基因重组技术;雄激素受体基因第一外显子区CAG重复序列缺失的突变重组体的成功构建可为今后的相关研究提供实验基础。  相似文献   
107.
目的:通过对图书馆员的人格因素和职业现状分析,为图书馆的人力资源管理提供参数。方法:于2005-06/08纳入大连理工大学伯川图书馆馆员72人作为人格测试组,男7人,女65人;同时纳入2005-07前在职的全部馆员122人作为职业现状分析组,男26人,女96人。采用国际公认的卡特尔16种人格因素问卷,对人格测试组进行人格测试。问卷从16个相对独立的人格维度对人进行描绘,全套测试题共187题,每题设有a,b,c3种可供选择的答案。将测试结果输入心理测试软件系统,给出粗分和标准分,再运用软件进行数据的统计分析。对职业现状分析组的全体馆员进行了性别,年龄结构,男女馆员在各工作部门的分布,及馆员的学历构成,技术职称和领导职务的担任比例统计分析。观察人格测试组卡特尔16种人格因素问卷人格类型的次元因素和综合个性应用评价分数,并对全体馆员的自然状况列表进行统计分析,分析其职业现状。结果:发放卡特尔16种人格因素问卷72份,回收完整问卷46份,回收率63.9%,有效率100%。最终人格测试组46人进入结果分析,男5人,女41人。职业现状分析组122人,全部进入结果分析。①人格测试组聪慧性、幻想性、自律性均高于全国专业技术人员常模,差异有显著性意义(9.74±1.22;8.88±1.22;13.11±2.36,11.83±1.25;13.89±2.59,12.40±1.47;t=4.780,3.676,3.901,2.783,P<0.001~0.01)。被试馆员怀疑性和紧张性低于全国专业技术人员常模,差异有显著性意义(9.39±2.85,10.56±1.57;9.76±3.72,11.19±1.65;t=-2.783,-2.606,P<0.01,0.05)。②女性图书馆员占总人数的78.7%,男性图书馆员在年龄结构上处于年龄段的两端,在生理上处于成年早期(30.7%)和晚期(38.4%);女性馆员的年龄集中于30~50岁的年龄段(86.3%)。③男馆员在综合办公室、自动化部和技术服务部的人数分布方面占据优势地位(38.4%,11.5%,11.5%);而女性馆员集中于期刊咨询部、文献建设部、流通阅览部和回溯建库等信息服务咨询部门(24%,15.6%,40.6%,4.2%)。④男馆员在获得博士、双学士、学士学位,及本科、中专学历方面的人数比例大于女性馆员,而女性馆员在获得硕士学位及大专和较低学历方面所占的比例大于男性馆员。⑤男性馆员在高级技术职称和馆级领导高端决策层占优势,在初级和较低技术职称中占比例较大;女性馆员在中级技术职称中级领导层上占比例大于男性馆员。结论:图书馆员女性化,而男性馆员在知识结构、职称、高端决策层领导职务的担任和承担高技术性工作方面的整体水平优于女性馆员。更应着重分析女性图书馆员的生理、心理特点,人格因素和职业特征,进行人力资源的优化组合。  相似文献   
108.
This paper addresses the problem of indexing shapes in medical image databases. Shapes of organs are often indicative of disease, making shape similarity queries important in medical image databases. Mathematically, shapes with landmarks belong to shape spaces which are curved manifolds with a well defined metric. The challenge in shape indexing is to index data in such curved spaces. One natural indexing scheme is to use metric trees, but metric trees are prone to inefficiency. This paper proposes a more efficient alternative.We show that it is possible to optimally embed finite sets of shapes in shape space into a Euclidean space. After embedding, classical coordinate-based trees can be used for efficient shape retrieval. The embedding proposed in the paper is optimal in the sense that it least distorts the partial Procrustes shape distance.The proposed indexing technique is used to retrieve images by vertebral shape from the NHANES II database of cervical and lumbar spine X-ray images maintained at the National Library of Medicine. Vertebral shape strongly correlates with the presence of osteophytes, and shape similarity retrieval is proposed as a tool for retrieval by osteophyte presence and severity.Experimental results included in the paper evaluate (1) the usefulness of shape similarity as a proxy for osteophytes, (2) the computational and disk access efficiency of the new indexing scheme, (3) the relative performance of indexing with embedding to the performance of indexing without embedding, and (4) the computational cost of indexing using the proposed embedding versus the cost of an alternate embedding. The experimental results clearly show the relevance of shape indexing and the advantage of using the proposed embedding.  相似文献   
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110.
BACKGROUND: A hemoglobin (Hb) standard of 115 g per L on the copper sulfate test has been in use by the Canadian Red Cross Society Blood Services for female blood donor predonation screening since 1989. STUDY DESIGN AND METHODS: To determine if this lowered Hb standard results in increased iron deficiency in repeat blood donors, a study was conducted to evaluate the performance of the copper sulfate test and predonation capillary and venous Hb assays in a population of female blood donors most at risk of developing iron deficiency. RESULTS: Of the 174 donors who were of childbearing age, who were not taking iron supplements, and who had made at least three blood donations per year, 45 (25.9%) were iron deficient, and 64 (36.8%) had reduced iron stores; only 65 (37.3%) had normal iron stores. This study showed that capillary blood is more likely to have a higher Hb concentration (3.2 +/− 7.8 g/L) than venous blood samples, which could affect the performance of predonation screening assays that are based on capillary blood samples at a given discriminating value. With an Hb standard of 115 g per L, both the copper sulfate and capillary Hb assays were not sensitive enough to screen for iron deficiency (sensitivity, 27% and 33%; specificity, 96% and 93%, respectively) and were comparable only to the performance of a venous Hb assay with a cutoff value of 110 g per L (sensitivity, 27%; specificity, 99%). In contrast, an Hb standard of 125 g per L in the copper sulfate test could achieve a more optimal sensitivity of 79 percent and specificity of 78 percent. CONCLUSION: This study supports the use of a higher Hb cutoff value of 125 g per L for female blood donors in the predonation fingerstick copper sulfate test.  相似文献   
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