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51.
The diagnosis of diabetes mellitus type 2 (DM2) is based either on increased plasma glucose or Glycated hemoglobin levels. Since these measures are the only means for diagnosis of DM2, they must be well adapted to each population according to their metabolic characteristics, given that these may vary in each population. The World Health Organization (WHO) determined the cut-points of plasma glucose levels for the diagnosis of DM2 by associating hyperglycemia with the risk of a specific microvascular complication-retinopathy. Cardiovascular diseases are however the principal causes of mortality in patients with DM2 and we reported that in the Colombo-Ecuadorian population impaired fasting glucose and impaired glucose tolerance are both risk markers for myocardial infarction. We propose that the current cut-points accepted by the WHO need to be revaluated in populations such as Latin America and that there should be lower cut points for glycaemia in this population, to reduce the prevalence of cardiovascular complications associated with DM2.  相似文献   
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笔者对已报道的经典名方药物考证相关研究进行系统梳理与分析,总结当前研究存在的问题与不足,提出经典名方药物考证要点建议,为经典名方药物考证相关研究提供借鉴。该文分别从注意古今药物考证内涵的异同、注重多维信息的综合利用、注重药物不同关键环节历史流变的梳理与考证、注重近代学名考订沿革梳理、注重尊古不泥古的考证原则、注重文献学基础知识等角度进行探讨,提出经典名方药物考证应对本草考证的现状、问题、成果进行深入的总结分析,吸收前人的优点,补充以往考证的不足,并在此基础上根据经典名方药物考证自身特点,形成特有的研究体系,注重历史变迁的脉络梳理,注重横断面分析,在全面分析基原、道地产区、药用部位与炮制等不同关键环节历史变迁基础上,充分吸收近现代研究成果,并结合当前生产力和认知水平,给出不同时期经典名方药物的合理关键信息,为经典名方的开发奠定坚实基础。  相似文献   
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目的 :探讨针刺肾俞穴配合闪罐法治疗肝郁脾虚型肥胖并发高脂血症的临床疗效。方法 :208例患者随机分为治疗组与对照组,每组104例,治疗组给予针刺肾俞穴配合闪罐法,对照组给予普通针刺治疗。观察两组患者治疗前后各项肥胖指标、血脂指标的变化,并统计临床疗效。结果:两组临床疗效总有效率分别为92.31%、74.04%,差异有统计学意义(P<0.05);治疗后治疗组与对照组在肥胖指标、血脂指标方面比较差异有统计学意义(P<0.05)。结论:针刺肾俞穴配合闪罐法治疗肥胖并发高脂血症具有减肥降脂双重作用,针刺肾俞穴配合闪罐法治疗肥胖并发高脂血症疗效优于普通针刺组。  相似文献   
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[目的]观察协定肢伤I方口服热敷治疗四肢闭合损伤疗效。[方法]使用大样本随机平行对照方法,将2468例门诊及住院患者按掷骰子法随机分为两组。对照组1212例协定肢伤I方(红花、延胡索各15g,桃仁、川芎、赤芍、生三七粉另包冲服、当归、泽泻、桂枝、牛膝、山楂各10g),1剂/d,水煎300mL,早晚温服;蜡疗机熬化粗石蜡装塑料袋敷于患处,12h/次。治疗组1256例协定肢伤I方药渣加水送入湿热敷机内与敷布同煮30min,于伤后或术后24h将敷布外套棉布贴敷于伤处,30min/次,2次/d;协定肢伤I方口服同对照组。连续治疗7d为1疗程。观测临床症状、疼痛积分、肿胀指数、不良反应。治疗1疗程,判定疗效。[结果]治疗组痊愈922例,显效248例,有效63例,无效23例,总有效率98.16%。对照组痊愈705例,显效278例,有效105例,无效124例,总有效率89.76%。治疗组疗效优于对照组(P0.05)。相关指标两组均有改善(P0.05),治疗组改善优于对照组(P0.05)。[结论]协定肢伤I方口服热敷治疗四肢闭合损伤效果显著,值得推广。  相似文献   
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The majority of papers included in the quarterly review discuss various aspects of dry needling (DN), which continues to be of interest to researchers and clinicians. A study by Liu et al. is the first paper to examine the effects of DN of acetylcholine, esterase and receptors. The study provides support for the integrated trigger point hypothesis and for DN. A paper by Hightower and colleagues found an intriguing link between low magnesium levels in the drink water supply, vitamin D, and myofascial pain, cancer, tendon ruptures, and colon polyps. Contributions originated in the Brazil, China, Germany, Iran, India, Poland, South Korea, Spain, Taiwan, Turkey, and the US.  相似文献   
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《Social neuroscience》2013,8(4):348-359
The cognitive and neural mechanisms leading to deception were studied by the event-related brain potential (ERP) technique. In a simulated deception situation with graded monetary incentives, participants made a decision to lie or be truthful in each trial and held their response until a delayed imperative signal was presented. Spatiotemporal principal component analysis (PCA) and source analysis revealed that brain activities dominant in the left lateral frontal area approximately 800–1,000 ms post-stimulus and over the central-frontal-parietal and right frontal areas after 1,300 ms were significantly more negative in the deceptive condition than in the truthful condition. These results suggest that two serial cognitive processes, decision making and response preparation, are related to deliberate deception.  相似文献   
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The Greenland Ice Sheet (GrIS) is a potentially unstable component of the Earth system and may exhibit a critical transition under ongoing global warming. Mass reductions of the GrIS have substantial impacts on global sea level and the speed of the Atlantic Meridional Overturning Circulation, due to the additional freshwater caused by increased meltwater runoff into the northern Atlantic. The stability of the GrIS depends crucially on the positive melt-elevation feedback (MEF), by which melt rates increase as the overall ice sheet height decreases under rising temperatures. Melting rates across Greenland have accelerated nonlinearly in recent decades, and models predict a critical temperature threshold beyond which the current ice sheet state is not maintainable. Here, we investigate long-term melt rate and ice sheet height reconstructions from the central-western GrIS in combination with model simulations to quantify the stability of this part of the GrIS. We reveal significant early-warning signals (EWS) indicating that the central-western GrIS is close to a critical transition. By relating the statistical EWS to underlying physical processes, our results suggest that the MEF plays a dominant role in the observed, ongoing destabilization of the central-western GrIS. Our results suggest substantial further GrIS mass loss in the near future and call for urgent, observation-constrained stability assessments of other parts of the GrIS.

During the last century, the Greenland Ice Sheet (GrIS) has lost mass at an accelerating rate (1, 2). The mass loss is caused by solid ice discharge into the North Atlantic and surface melting due to increasing temperatures. The relative contribution of the latter has increased from 42% before 2005 to 68% between 2009 and 2012, and surface runoff caused 84% of the increase in mass reduction since 2009 (3). The complete melting of the GrIS would cause a global sea level rise of more than 7 m (4, 5). Continued melting of the GrIS has been suggested to potentially lead to a collapse of the Atlantic Meridional Overturning Circulation via increased freshwater flux into the North Atlantic (6, 7), which may, in turn, trigger a cascade of transitions in additional tipping elements such as the Amazon rainforest and the tropical monsoon systems (6, 810).In addition to the centennial-scale variability associated with the increasing trend in mean temperatures related to anthropogenic climate change, the pace of mass loss has decadal-scale fluctuations caused by natural variations in external oceanic and atmospheric forcing. The imprints of these natural, decadal-scale fluctuations are spatially heterogeneous across the GrIS. Since the early 2000s, periods of persistently negative phases of the North Atlantic Oscillation (NAO) and a positive phase of the East Atlantic Pattern (11) have led to a weakening and southward shift of the jet stream, and more persistent blocking (12) over Greenland during summer, resulting in overall increased mass reduction rates (2, 13). On the other hand, a slowing down of mass loss since 2013—which inverted again in 2019—was caused by more periods with a persistent positive NAO (14). Moreover, recent observations show that the Jakobshavn glacier has been advancing again since 2016 due to anomalous wintertime heat loss in the boundary current around southern Greenland (15). However, these natural fluctuations do not have a sustained impact on melt rates comparable to the longer-term trend toward overall increasing melt rates caused by anthropogenic global warming (Fig. 1A).Open in a separate windowFig. 1.(A) Summer sea level temperatures from the Ilulissat station in CWG (25) (blue curves) and Arctic temperature anomalies (26) (red curves). The linear trend of the station data (dashed blue curve) corresponds to 1.3°C warming per century. Arctic temperature anomalies are shown only for comparison; only the station data (blue curves) are used for our analysis. (B) Melt rates from the CWG ice core stack (blue curve) and the NU peninsula core (red curve), given as z scores with respect to a normal distribution (18). (C) Detrended logarithmic CWG (blue curve) and NU (red curve) melt rates. A Gaussian filter with bandwidth σ=30 y was used for detrending. The runoff and melt time series are preprocessed in this way before computing the EWS indicators to exclude potential biases by underlying trends; in particular, we take the logarithm of the melt rates in order to account for skewed data distributions. (D) The variance of the CWG (blue curves) and NU (red curves) melt rates. (E) The AC1 of the CWG (blue curves) and NU (red curves) melt rates. Note that the AC1, despite a significantly positive trend, appears to have at least temporarily stabilized in the last few decades. It should be noted, however, that the AC1 is generally influenced by (multi)decadal variability (27). The window size for computing the variance and the AC1 is w=70 y, and values are plotted at the windows’ endpoints. Data for the first w=70 y are omitted to ensure that all windows contain the same number of data points. The dashed lines in D and E indicate linear trends of the variance and AC1, and P values for positive slopes as determined from a phase surrogate test are indicated in the legend (see Materials and Methods). The statistical significance of the positive trends is robust across wide ranges of the bandwidth σ and the sliding window size (SI Appendix, Fig. S1).Early model simulations suggest that melting of the GrIS is inevitable beyond a critical global mean temperature threshold of 0.8°C to 3.2°C above preindustrial levels, with a best estimate of 1.6°C (16). More recent comprehensive modeling results show that, for the representative concentration pathway 8.5 (RCP8.5), the GrIS melts entirely until AD 3000 (5). Arctic temperatures have increased more than the global average (17) (Fig. 1A), and the nonlinear increase in GrIS melt rates and runoff that have recently been detected (18) (Fig. 1B) suggests that the critical temperature threshold may be closer than previously thought. We emphasize that the surface mass balance turning negative is not a necessary condition for stability loss, and the temperature may reach a critical threshold years before a turning point in the mass balance (16).Idealized models of critical transitions in natural systems suggest that the loss of stability of an equilibrium (fixed point) is observable before the abrupt transition (19). In dynamical systems with random forcing, one can show that, if a system approaches a bifurcation where an equilibrium point loses its stability, the variance of the fluctuations around the equilibrium will increase, as will the characteristic decay time of the autocorrelation function of these fluctuations. The change in dynamics that occurs as stability is lost is often called critical slowing down, and the associated statistical precursor signs in terms of rising variance and lag-one autocorrelation (AC1) are called early-warning signals (EWS) (19). Such statistical EWS associated with critical slowing down are, for example, detectable in the temperature proxy from the North Greenland Ice Core Project before several of the Dansgaard–Oeschger events of the last glacial interval (20, 21), as well as before other abrupt transitions in past climates (22). In the context of anthropogenic global warming, EWS are expected to precede potential abrupt transitions in the Earth system’s major tipping elements, such as the polar ice sheets, the Atlantic Meridional Overturning Circulation, or the tropical monsoon systems (23). We investigate here a possible tipping point for the GrIS based on the theory of critical slowing down.In the following, we will first show that central-western Greenland (CWG) melt rates exhibit robust and significant EWS. We then reconstruct the corresponding CWG ice sheet height changes and show that they can be captured well by a simple model focusing on the melt elevation feedback (MEF). We then demonstrate that pronounced EWS can also be found in the fluctuations of the reconstructed ice sheet height around the equilibrium of the model and show that these EWS are consistent with the theoretical expectations provided by the MEF model.  相似文献   
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