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1.
内生菌由细菌、真菌、古菌和原生生物组成,它们生活在植物的活体组织中,具有丰富的次级代谢产物多样性。人参内生菌在人参的生长发育、次级代谢产物的生成和环境适应等方面均有重要的促进作用,对人参的产量和品质有较大影响。随着人们在微生物领域研究的深入,高通量测序技术已经成为研究植物内生菌的重要方法。文章主要从人参内生菌分离与鉴定研究方法、人参内生菌的多样性、人参内生菌及其次级代谢产物的活性、人参内生菌对宿主的影响等4个方面对人参内生菌近年来的研究进展进行讨论,并对其发展方向提出展望,以期为药用植物内生菌研究和品质改良提供新思路、新方法。  相似文献   
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The Poisson-Nernst-Planck (PNP) system is a widely accepted model for simulation of ionic channels. In this paper, we design, analyze, and numerically validate a second order unconditional positivity-preserving scheme for solving a reduced PNP system, which can well approximate the three dimensional ion channel problem. Positivity of numerical solutions is proven to hold true independent of the size of time steps and the choice of the Poisson solver. The scheme is easy to implement without resorting to any iteration method. Several numerical examples further confirm the positivity-preserving property, and demonstrate the accuracy, efficiency, and robustness of the proposed scheme, as well as the fast approach to steady states.  相似文献   
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Objective The present study aims to investigate the concentrations of Hg and its aspects methyl mercury(Me-Hg) and inorganic mercury(I-Hg) in the biological samples(BSs) of fluorescent lamp industries workers(FLIWs).Methodology Different BSs including red blood cells(RBCs),plasma,urine,hair and nails were collected from the workers exposed to Hg and unexposed persons were selected as control group to measure both the T-Hg concentration as well as its species in different biological samples through quantitative analysis.Health data was collected through questionnaire survey.Results The mean concentrations of T-Hg(31.9 μg/L),Me-Hg(27.7 μg/L),and I-Hg(5.36 μg/L) in RBCs were found significantly(P 0.001) higher among the workers(n = 40) as compared to the control group(n = 40).Similarly the mean Hg concentrations in plasma,urine,hair and nails were also significantly higher among the workers than the control group.The statistical relation between Hg concentration and demographic characteristics observed that workers experience and fish consumption has increased the Hg concentration while age,weight and smoking found no significant effect on Hg concentration in the BSs.Conclusion The study observed that the workers were highly exposed to high concentration of Hg and they are at a high health risk.  相似文献   
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《The Journal of arthroplasty》2022,37(10):1945-1950
The results of statistical tests in orthopedic studies are typically reported using P-values. If a P-value is smaller than the pre-determined level of significance (eg, < .05), the null hypothesis is rejected in support of the alternative. This automaticity in interpreting statistical results without consideration of the power of the study has been denounced over the years by statisticians, since it can potentially lead to misinterpretation of the study conclusions. In this paper, we review fundamental misconceptions and misinterpretations of P-values and power, along with their connection with confidence intervals, and we provide guidelines to orthopedic researchers for evaluating and reporting study results. We provide real-world orthopedic examples to illustrate the main concepts. Please visit the following https://youtu.be/bdPU4luYmF0 for videos that explain the highlights of the paper in practical terms.  相似文献   
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The Local Lymph Node Assay (LLNA) is the most common in vivo regulatory toxicology test for skin sensitisation, quantifying potency as the EC3, the concentration of chemical giving a threefold increase in thymidine uptake in the local lymph node. Existing LLNA data can, along with clinical data, provide useful comparator information on the potency of sensitisers. Understanding of the biological variability of data from LLNA studies is important for those developing non-animal based risk assessment approaches for skin allergy. Here an existing set of 94 EC3 values for 12 chemicals, all tested at least three times in the same vehicle have been analysed by calculating standard deviations (SD) for logEC3 values. The SDs range from 0.08 to 0.22. The overall SD for the 94 logEC3 values is 0.147. Thus the 95% confidence limits (2xSD) for LLNA EC3 values are within a factor of 2, comparable to those for physico-chemical measurements such as partition coefficients and solubility. The residual SDs of Quantitative Mechanistic Models (QMMs) based on physical organic chemistry parameters are similar to the overall SD of the LLNA, indicating that QMMs of this type are unlikely to be bettered for predictive accuracy.  相似文献   
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金丽梅 《中外医疗》2016,(25):185-186
目的:探讨彩色多普勒超声诊断卵巢肿瘤蒂扭转的临床意义。方法方便选取2012―2015年该院收治的58例疑似卵巢肿瘤蒂扭转患者作为观察目标,入选病例均应用彩色多普勒超声进行检查,并将检查结果同术后病理检查结果进行比较。结果58例患者中,术后病理证实卵巢肿瘤蒂扭转者51例,彩色多普勒超声共确诊49例,检查准确率为96.1%;囊壁增厚、腹腔或盆腔积液、可见混合型团块是卵巢肿瘤蒂扭转的主要彩超表现。结论卵巢肿瘤蒂扭转应用彩色多普勒超声诊断,可显著提高诊断准确率,具有积极的临床使用和推广价值。  相似文献   
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Klinefelter syndrome (KS) (47,XXY) is the most common aneuploidy (1/650) of sexual chromosome among male (0,1 à 0,2 % of male population) (Hong and Reiss, 2014). Because its large physical phenotypic variability (high tall, sparse hairiness, gynecomastia), this syndrome is largely underdiagnosed (less than 25 % of affected persons) (Samango-Sprouse et al., 2018). Nevertheless, cognitive variability is smaller. Normal to low average total IQ, low verbal IQ, social problems and high levels of psychiatric comorbidities including early aggressiveness are commonly described (Hong and Reiss, 2014). In Denmark, higher risks of committing sexual crime and arson (compared to criminal controls) was recently reported (Stochholm et al., 2012). Quite a few clinically relevant cases reports scattered in the literature, suggests the presence of a pattern of a specific subtype of KS inpatients among forensic population (Bénézech, 1975). However, very few studies provide quantitative or qualitative pertaining to robust results. KS well-documented neurobiological (van Rijn, 2018) (e.g. low levels of testosterone), neuropsychological (Bénézech, 1975; Hong and Reiss, 2014; Samango-Sprouse et al., 2018; Savic, 2012; Seara-Cardoso et al., 2016; Senon, 2005; Stochholm et al., 2012; van Rijn, 2018; van Rijn et al., 2008; van Rijn et al., 2018; van Rijn et al., 2014; van Rijn et al., 2012) [29] (e.g. alterations of both complex cerebral — attention, empathy — and behavioral regulation functions - inhibition, mental flexibility, emotional response modulation, control of own actions) and neuroanatomical (Hong and Reiss, 2014; Itti et al., 2003; Savic, 2012; van Rijn et al., 2008; van Rijn et al., 2012) [29] (e.g. limbic system and temporal lobe abnormal volume, hemispheric specialization shortcoming) features may be helpful to understand comorbid symptoms psychopathology. Numbers of recent studies conduct on KS pediatric or adult population provide interesting results on conduct, anxiety, psychotic and autism spectrum disorders. In addition, some authors use genetic and epigenetic specific features of sex chromosome aneuploidies (e.g. X genes neurodevelopmental role; imprinting) in order to clarify genotype-phenotype links of comorbid symptoms (Bruining et al., 2011; Zitzmann et al., 2004;). With Belgian colleagues from the Social Defense Research Center (CRDS, Tournai, Belgium), we are currently recruiting KS inpatients from security hospitals or psychiatric units in Belgium and France. We aim to assess psychopathic traits with the Psychopathy Checklist Revised (PCL-R, Hare) (Hare, 2003). Our first results concerning 3 KS males outline that PCL-R is useful for the characterization of clinical phenotype among KS forensic sample. While three of them present psychopathic traits, two of them present categorical double diagnose “psychopathy-KS” (total PCL-R score > = 30/40 (Delannoy et al., 2017)). Moreover, dimensional analysis support our hypothesis of a higher prevalence of “explosive profile” in comparison to other psychopathic profiles in our sample (Delannoy et al., 2017). The present article summarizes historic background (e.g. “psychopathy” disappearance of mental disorder reference classification schemes, “crime chromosome” (Bénézech, 1975)) and current context argues (e.g. French psychiatrists court experts widely refer to psychopathy concept despite a lack of consensual definition (Senon, 2005), weak knowledge and training of PCL-R and its related biopsychological recent findings (Blair, 2013; de Oliveira-Souza et al., 2008; Dotterer et al., 2017; Glenn and Raine, 2014; Hosking et al., 2017; Korponay et al., 2017; Pham, 1995; Pham, 2005; Raine, 2008; Raine et al., 2003); stigma and discrimination apprehensions of KS and psychopath) that motivate our research project. Finally, we discuss the advantages of our research protocol on KS participants assessed with PCL-R, such as tackling stigma and discrimination, better understanding psychopathology, and clarifying murky interactions of biological, psychological and social factors entangled in the development of these two fascinating troubles.  相似文献   
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