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101.
本文探讨了菊科9种植物和地胆草的4种对口商品药材基因组DNA提取与纯化的原理、方法通过对3种常用植物基因组DNA提取方法(CsCl梯度超速离心法、CTABCsCl梯度超速离心法和CTAB微量提取法)的条件摸索在DNA产率、纯度以及提取纯化过程中影响PCR扩增因子方面进行比较,认为CTAB微量提取法是植物类药材基因组DNA一种比较省时、有效、经济的提取方法  相似文献   
102.
石斛属4种植物的AFLP分析   总被引:36,自引:2,他引:36  
虞泓  和锐  倪念春  张时刚 《中草药》2004,35(7):808-810
目的 研究石斛属植物DNA指纹图谱,初步探讨AFLP分子标记技术在石斛地道性鉴别上的应用。方法采用扩增片段长度多态性(AFLP)技术对石斛属内石斛组4个种和一个外类群种进行基因组DNA多态性分析。结果从64对引物组合中选出5对引物组合构建了5个种的DNA指纹图谱。通过聚类分析,石斛属4种植物聚成一个大类,彼此关系得到了很好的分辨,并获得bootstrap校验的有力支持。结论AFLP技术可用于药用石斛DNA指纹图谱研究。  相似文献   
103.
李烨  王波  邓存良 《西部医学》2019,31(1):65-69
【摘要】 目的 比较不同临床结局乙肝病毒(HBV)相关重型肝炎和正常人血浆中的蛋白质指纹图谱,筛选出与重型肝炎预后相关的差异蛋白,为重型肝炎预后判断提供依据。方法 采用CM10联合表面增强激光解析 飞行时间 质谱(SELDI TOF MS)技术,检测35例HBV相关重型肝炎和15例正常人血浆蛋白质谱获得血浆蛋白指纹图谱。结果 HBV相关重型肝炎和正常人血浆中一共检测出57个蛋白峰,最终筛选出M/Z为M3492 79、M5649 11、M3936 56、M7568 86、M8601 12的5个差异蛋白峰建立分类树模型,该模型对重型肝炎预后判断的敏感性为7200%,特异性为10000%,准确性为80%。结论 SELDI TOF MS技术可以用于重型肝炎患者预后相关血浆蛋白的筛选,利用这些差异表达的蛋白建立的分类树模型对重型肝炎患者预后判断具有重要的临床价值。  相似文献   
104.
Preprocessing choices present a particular challenge for researchers working with functional magnetic resonance imaging (fMRI) data from young children. Steps which have been shown to be important for mitigating head motion, such as censoring and global signal regression (GSR), remain controversial, and benchmarking studies comparing preprocessing pipelines have been conducted using resting data from older participants who tend to move less than young children. Here, we conducted benchmarking of fMRI preprocessing steps in a population with high head-motion, children aged 4–8 years, leveraging a unique longitudinal, passive viewing fMRI dataset. We systematically investigated combinations of global signal regression (GSR), volume censoring, and ICA-AROMA. Pipelines were compared using previously established metrics of noise removal as well as metrics sensitive to recovery of individual differences (i.e., connectome fingerprinting), and stimulus-evoked responses (i.e., intersubject correlations; ISC). We found that: 1) the most efficacious pipeline for both noise removal and information recovery included censoring, GSR, bandpass filtering, and head motion parameter (HMP) regression, 2) ICA-AROMA performed similarly to HMP regression and did not obviate the need for censoring, 3) GSR had a minimal impact on connectome fingerprinting but improved ISC, and 4) the strictest censoring approaches reduced motion correlated edges but negatively impacted identifiability.  相似文献   
105.
Quercetin, a fiavonoid, is found in many fruits and vegetables. This drug was previously shown to affect the metastatic potential of mouse tumor cells. Mutagenicity of quercetin was examined by means of DNA fingerprint analysis using the Pc-1 probe that efficiently detects mutations due to recombination. Treatment of BMT-11 and FM3A tumor cells with 55 μM quercetin resulted in gain and loss of bands in the fingerprints in both cell lines. The frequencies of the clones having undergone mutation were 3/11 and 6/26, respectively. This suggests that quercetin is mutagenic and induces recombination. This result seems to provide a molecular basis for the phenotypic variations of BMT-11 tumor cells induced by quercetin.  相似文献   
106.
Sixty-three isolates of Actinomyces naeslundii genospecies 1 and 2 and Actinomyces odontolyticus from three subjects clustered into 22 ribotypes. Unique ribotypes were found in the subjects and within individual tissue sites (bucca, tooth and tongue). A. odontolyticus ribotypes shared tongue-specific binding properties, while those of genospecies 1 and 2 from buccal and tooth surfaces shared different types of N-acetyl-β-d -galactosamine binding specificity.  相似文献   
107.
A simple method for identification of individuals and maternity testing has been developed. This technique includes PCR amplification of the 199-bp hypervariable portion of the noncoding region of human mtDNA, digestion with RsaI and subsequent SSCP analysis of restriction fragments with DNA silver staining. Using this approach we have analysed the DNA fingerprint patterns of the family members. The fingerprints of maternally related individuals appeared to be identical in three generations, while maternally unrelated members of the family showed differences in their fingerprints, either in SSCP or both RFLP and SSCP patterns. Sequencing data have confirmed the results obtained. Further DNA fingerprinting analysis of 19 unrelated mother–child pairs by means of the method described revealed complete identity of the fingerprint patterns within the pairs. The probability of a random fingerprint match for two maternally unrelated individuals was estimated as 8%. © 1994 Wiley-Liss, Inc.  相似文献   
108.
Summary The incidence of pulmonary tuberculosis among newspaper vendors, tram operators, and other exposed groups leads to repeated discussions about the importance of single cases for the spread of tuberculous infection. We subjected 36 strains of Mycobacterium tuberculosis, isolated in 1992 from 31 patients, to restriction fragment length polymorphism analysis using PvuII and an insertion element 986 probe. Only two isolates obtained from a married couple showed the same DNA fingerprinting pattern, all the other strains had unique and clearly distinguishable banding patterns. Our investigation revealed no dominating strains except in the case of one married couple, where the chain of infection was obvious (the wife being diagnosed during the course of testing of her alcoholic and tuberculous husband's contacts). The main emphasis in the fight against tuberculosis still rests on securing the availability of diagnostic and therapeutic means for all patients with tuberculosis. The importance of single infected source cases for the spread of tuberculosis should not be overestimated.Abbreviations IS insertion sequence - RFLP restriction fragment length polymorphism  相似文献   
109.
Diagnostic errors occur in the preanalytic, analytic, and postanalytic phases of specimen processing. Correlating clinical and imaging information with gross and microscopic findings is crucial to limit errors and unnecessary treatment. Herein, we report the case of a 54-year-old woman who presented with left breast bloody nipple discharge and subsequently underwent central duct excision. Pathology revealed a high-grade sarcoma. The patient presented to our institution for further management. Upon secondary pathology review and DNA fingerprinting analysis, the correct interpretation was rendered. Our case demonstrates the importance of clinical correlation and review of pathology slides prior to definitive therapy.  相似文献   
110.
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