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A 70-year-old female was referred for brown-to-gray colored papules and nodules on her lower legs. She had been diagnosed with diffuse large B-cell lymphoma (DLBCL) in her stomach, and myelodysplastic syndrome (MDS) by bone marrow biopsy. Three years after complete remission of DLBCL, she experienced DLBCL recurrence in her small bowel and was hospitalized. MDS had been stationary, but during the treatment of DLBCL, her laboratory findings suggested signs of leukemia. Bone marrow biopsy was done, and acute monoblastic leukemia (AMoL) was diagnosed. After 1 cycle of chemotherapy for AMoL, skin lesions developed, and her skin biopsy showed cutaneous T-cell lymphoma (CTCL). Terminal deoxynucleotidyl transferase staining and CD123 staining were negative, and bone marrow re-biopsy conducted after the skin lesion developed still showed monoblastic proliferation. Whether the CTCL represented with an AMoL lineage switch could not be completely proved due to the absence of molecular or clonal marker evaluations, but the possibility of coexistence of three different malignancies was higher. During treatment, a neutropenic fever developed, and the patient died due to sepsis. We herein report a rare case of CTCL accompanied by AmoL and DLBCL.  相似文献   
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ObjectiveLegionella pneumophila serogroup 1 (Lp1) sequence type (ST) 1 is globally widespread in the environment and accounts for a significant proportion of Legionella infections, including nosocomial Legionnaires' disease (LD). This study aimed to design a sensitive and specific detection method for Lp ST1 that will underpin epidemiological investigations and risk assessment.MethodsA total of 628 Lp genomes (126 ST1s) were analyzed by comparative genomics. Interrogation of more than 900 accessory genes revealed seven candidate targets for specific ST1 detection and specific primers and hydrolysis probes were designed and evaluated. The analytical sensitivity and specificity of the seven primer and probe sets were evaluated on serially diluted DNA extracted from the reference strain CIP107629 and via qPCR applied on 200 characterized isolates. The diagnostic performance of the assay was evaluated on 142 culture-proven clinical samples from LD cases and a real-life investigation of a case cluster.ResultsOf seven qPCR assays that underwent analytical validation, one PCR target (lpp1868) showed higher sensitivity and specificity for ST1 and ST1-like strains. The diagnostic performance of the assay using respiratory samples corresponded to a sensitivity of 95% (19/20) (95% CI (75.1–99.9)) and specificity of 100% (122/122) (95% CI (97–100)). The ST1 PCR assay could link two out of three culture-negative hospitalized LD cases to ST1 during a real-time investigation.ConclusionUsing whole genome sequencing (WGS) data, we developed and validated a sensitive and specific qPCR assay for the detection of Lp1 belonging to the ST1 clonal complex by amplification of the lpp1868 gene. The ST1 qPCR is expected to deliver an added value for Lp control and prevention, in conjunction with other recently developed molecular assays.  相似文献   
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目的 研究甲胎蛋白(Afp)阳性细胞的增殖分化在组织生长修复,肿瘤发生过程中的作用,建立Afp-CreERT转基因小鼠细胞示踪系统.方法 采用DNA雄原核显微注射方法获得Afp-CreERT转基因小鼠,筛选出合适的品系后,使之与Rosa26-lacZ工具小鼠杂交,获得Cre/lacZ双阳性的Afp-cre-lacZ转基因小鼠.结果 显微注射后,共出生小鼠56只,经PCR鉴定Cre阳性小鼠共4只,阳性小鼠传代后各为一系.筛选内源性Afp表达与Cre表达相对符合的品系作为Afp-CreERT转基因小鼠品系建系.Afp-CreERT转基因小鼠与Rosa26-lacZ工具小鼠杂交,经PCR鉴定后获得Cre/lacZ双阳性的Afp-cre-lacZ转基因小鼠.经实时PCR,X-gal染色,免疫荧光染色鉴定后得到Afp-cre-lacZ转基因小鼠细胞示踪系统,同时证实该系统能够正确示踪Afp表达阳性的细胞,同时也能够应用于肝损伤小鼠模型中.结论 成功构建了Afp-cre-lacZ转基因小鼠细胞示踪系统,为研究这类细胞的谱系发生提供了工具.  相似文献   
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目的 研究中国流行的结核分枝杆菌谱系2的遗传结构和地理分布,为制定结核病防控策略提供科学依据。方法 采用标准15位点分枝杆菌散在重复单位-数目可变串联重复序列(variable number tandem repeats,VNTR)技术对来自全国31省市抽样调查的2 900株结核分枝杆菌谱系2进行基因分型。基于上述菌株15-VNTR数据,采用贝叶斯聚类法STRUCTURE进行群体遗传结构分析;构建邻接(Neighbor-Joining,NJ)树和最小生成树(Minimum Spanning Trees,MST)进行群体遗传分化分析。运用主成分分析(principal component analysis,PCA)验证。结果 STRUCTURE分析显示谱系2可分为4个亚群;MST拓扑结构提示亚群2位于奠基者位置,较古老;其他亚群(亚群1、3、4)位于分枝位置,较现代。亚群2主要分布于西南地区和东北三省;亚群1,3,4主要分布于我国东中部地区,推测由于人口的迁徙,造成菌株间遗传距离较近,由东北地区向东中部地区传播。主成分分析显示4群菌株分化不明显。结论 结核分枝杆菌谱系2可分为4个亚群,各亚群的遗传地理分布不同,上述结果对制定我国精准结核病防控策略将产生积极影响。  相似文献   
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Acute leukemias of ambiguous lineage (ALAL), including mixed phenotype acute leukemia (MPAL) and related entities such as early T-cell precursor acute leukemia (ETP-ALL), remain diagnostic and clinical challenges due to limited understanding of pathogenesis, reliance of immunophenotyping to classify disease, and the lack of a rational approach to guide selection of appropriate therapy. Recent studies utilizing genomic sequencing and complementary approaches have provided key insights that are changing the way in which such leukemias are classified, and potentially, treated. Several recurrent genomic alterations define leukemias that straddle immunophenotypic entities, such as ZNF384-rearranged childhood B-ALL and B/myeloid MPAL, and BCL11B-rearranged T/myeloid MPAL, ETP-ALL and AML. In contrast, some cases of MPAL represent canonical ALL/AML entities exhibiting lineage aberrancy. For many cases of ALAL, experimental approaches indicate lineage aberrancy arises from acquisition of a founding genetic alteration into a hematopoietic stem or progenitor cell. Determination of optimal therapeutic approach requires genomic characterization of uniformly treated ALAL patients in prospective studies, but several approaches, including kinase inhibitors and BH3 mimetics may be efficacious in subsets of ALAL.  相似文献   
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中国不同地区狂犬病病毒种群分布的差异   总被引:1,自引:0,他引:1       下载免费PDF全文
目的 明确我国不同地区流行的狂犬病病毒种群类别及其流行特征。方法 汇总GenBank数据库所有中国狂犬病流行株的N、G和全基因组序列以及国家狂犬病实验室新测定毒株序列,分别构建N基因和G基因种系发生树,明确每个毒株的种群归属。统计各地区流行株的种群类别及不同种群的毒株数量。结果 全国共流行6个毒株群(ChinaⅠ~Ⅵ),云南和湖南是我国大陆种群最丰富省份,均有多达4个群流行;河南、福建等6省份均有3个毒株群流行;上海、江西等8省份皆流行2个病毒种群;北京、天津等14省份目前只监测到1个毒株群流行。优势毒株群ChinaⅠ已蔓延至我国东北部和西部地区,共计覆盖25个省份;China Ⅲ群近年在内蒙古、新疆地区的野生动物中流行且溢出至家畜中;China Ⅳ是青海、西藏地区的流行种群,同时流行于内蒙古、黑龙江地区的野生动物中。结论 我国不同地区狂犬病病毒种群类别和数量差异明显。  相似文献   
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