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11.
Deck officers on coastal tankers may be exposed to high concentrations of cargo vapors during loading and tank-cleaning operations. Two cases of acute nonlymphatic leukemia are described. Both men had worked as chief officers on coastal tankers transporting benzene and other petroleum products.  相似文献   
12.
Summary The spontaneous contractions of segments of rat portal veins have been examined in vitro under isotonic and isometric conditions. The power density spectra of recorded time series lasting 10–60 min were calculated. The spectra usually consist of harmonic frequency components. Only during shorter periods of analysis (10 min time series) we sometimes found additional non-harmonic components. All frequency components are proportionally shifted by changes of the bath temperature according to an average Q10 of 2.0. Increase of the load decreases the frequency of the contractions.The results of the spectral analysis, indicating a preponderance of a single source of periodicity, were supported by direct evidence of a pacemaker region. By recording contractions after systematic dissections of the portal vein segment, we found that spontaneous activity is generated at the central end of the segment.This work was supported by the Austrian Research Fund  相似文献   
13.
医学图像序列压缩是远程医疗系统中的重要技术,而运动估计在视频序列压缩中起着关键作用。我们提出了一种改进的正方形-菱形搜索算法来实现医学图像序列的运动估计。这种改进的正方形-菱形算法减少了搜索点数。我们将其应用于小波域的医学图像序列的运动估计,并对数字减影血管造影图像序列(DSA)进行实验。结果表明,改进后的小波域正方形-菱形算法较其他算法精度高。  相似文献   
14.
The extent to which individuals with Parkinson's disease (PD) show lability in optimism was explored in the present study. The relationship between optimism and perceived disease severity was examined as well. Twelve individuals diagnosed with PD completed self-report measures for 70 consecutive days. All individuals in this study showed lability in optimism over short time periods; however, 67% of the sample showed no pervasive negative changes in optimism over time. Increased levels of optimism on one day were predictive of decreased perceived disease severity the next day for one-fourth of the sample, after controlling for negative affect. Individual differences in the relationship between optimism and disease severity provided support for the idea that living with chronic illness has no monolithic meaning. More optimistic individuals reported less need for assistance with basic functional abilities than less optimistic individuals. The usefulness of lability in optimism among individuals with PD is discussed.  相似文献   
15.
A survey is presented of techniques which transform heart-rate variability data into a signal that is both visually informative and accessible for analysis. The Instantaneous Heart-Rate (IHR) signal is introduced, i.e. the signal having the value of the heart rate (inverse interbeat interval) during the interval concerned. The IHR signal differs from the standard Delayed Heart-Rate (DHR) signal, which is always one beat late. The relationship is discussed between the different representation methods and the Integral Pulse Frequency Modulation (IPFM) model, the latter being a physiologically plausible model for the transformation of a continuous input signal (e.g., nervous influence on the cardiac pacemaker) into a series of events (heartbeats). It is shown that when the IHR signal is used as input of the IPFM model, the event series from which the signal was derived appears at the output. Hence, if the IPFM model is accepted as a model of the pacemaker, the IHR signal may be considered as an approximation of the neural (sympathetic and parasympathetic) influence on the pacemaker. In addition we show that the appearance of the IHR signal is less affected by trigger errors or extrasystoles than the standard DHR signal. It is concluded that the most attractive time-domain representation of physiological event series consists of the IHR signal, because this signal, being conceptually and computationally simple, is consistent with the IPFM model.  相似文献   
16.
局限性癫痫脑电时间序列的分形维数计算比较   总被引:1,自引:0,他引:1  
为探索应用非线性动力学理论诊断癫痫病的新方法,对局限性癫痫病患者脑电时间序列进行了相关维数(Dc)和波形维数(Dw)的计算比较。观察到,痫性导联脑电的分形维数多低于对侧导联的值;相关维数Dc的相对变化量较波形维数Dw大;而波形维数Dw对痫性棘波敏感;结果提示,脑电时间序列的分形维数有可能成为诊断癫痫的特征参数,值得进一步深入研究。  相似文献   
17.
A total of 230 patients had planned single or multiple reoperative procedures following "curative" resection of colorectal cancer at the University of Minnesota. The site of the primary lesion was extrapelvic in 91, and later evidence of cancer was found in 58 patients (64%) at re-operation and/or other follow-up. Eight of the 58 (14%) were converted to disease-free status. Incidence and patterns of failure were correlated with initial operative-pathologic extent of disease (87 of the 91 at risk had initial tumor extension beyond the bowel wall, involved nodes or both) and comparisons were made with the previously analyzed rectal reoperation patients. While a component of local-regional failure was more common with rectal lesions (48/74 at risk, 65%), it was not uncommon with extrapelvic primaries (44/91-48%). The incidence of hematogenous metastasis (DM) was equal, but the pattern of initial DM differed (extrapelvic colon--primarily liver; rectum--liver and lung). Peritoneal seeding was a more common component of failure with the extrapelvic primaries (19/91--21% vs 3/74-4%). Since surgery alone is inadequate treatment for many patients with colon as well as rectal cancer, the rationale of adjuvant radiation and systemic therapy, alone or in combination, is discussed.  相似文献   
18.
目的 探讨季节性时间序列模型(autoregressive integrated moving average,ARIMA)在新疆肺结核发病预测中的应用,并验证模型的可行性和适用性。 方法 采用季节性ARIMA(p, d, q )(P, D, Q)s拟合2005年1月—2019年8月新疆地区肺结核月发病人数,建立多个季节时间序列模型并进行比较,选出最优模型对2019年9—12月肺结核发病人数进行预测。 结果 2005年1月—2019年8月新疆地区肺结核累积发病人数为627 869例,年平均发病人数为3 567例。 新疆地区肺结核月发病数具有季节性,1—5月平均发病数高于平均水平,6—12月平均发病数低于平均水平,发病高峰为1月和3月,发病低谷为9月。通过赤池信息量(Akaike Information Criterion,AIC)和贝叶斯信息量(Bayesian Information Criterion,BIC)最小原则得出,ARIMA(1, 1, 1 )(0, 1, 2)12是最优模型,其残差序列为白噪声,参数的回归系数均具有统计学意义,拟合的平均绝对百分比误差MAPE为8.723%。预测的MAPE为18.674%,真实值均处于预测值的95%置信区间内。 结论 ARIMA(1, 1, 1 )(0, 1, 2)12模型能够较好地拟合新疆肺结核发病数据,并进行短期预测,对新疆卫生防控措施的制定具有一定指导意义。  相似文献   
19.
目的 探讨ARIMA-GRNN组合模型在城乡居民基本医疗保险的医保补偿住院费用预测中的应用,比较它与ARIMA模型预测的效果。方法 收集2016年1月至2020年12月河南某市城乡居民基本医疗保险的住院补偿费用,使用Matlab R2016a建立ARIMA-GRNN组合模型,使用R 4.0.3建立ARIMA模型,用2020年5月至12月的数据对两模型的预测效果做评价。结果 ARIMA(0,1,1)(1,0,0)12模型相对最优,其拟合部分的MAE、MAPE、RMSE分别为3998.4、10.9%、5642.9,预测部分的MAE、MAPE、RMSE分别为6521.9、16.5%、6675.8。ARIMA-GRNN模型最优光滑因子为0.166,其拟合部分的MAE、MAPE、RMSE分别为4044.5、11.1%、5622.0,预测部分的MAE、MAPE、RMSE分别为5831.8、14.8%、6013.7。结论 ARIMA-GRNN组合模型预测效果比单纯ARIMA模型好,可短期预测医保补偿住院费用。  相似文献   
20.
目的 分析2006—2017年贵州省肺结核流行特征,为全省肺结核防控提供依据。方法 采用描述性流行病方法分析2006—2017年贵州省肺结核报告发病率,用动态数列法分析9个市/州不同阶段的变化。结果 2006—2017年全省肺结核总发病617 115例,平均发病率为142.15/10万,总体呈下降趋势(χ2趋势= 932.07,P<0.01);遵义、铜仁、安顺市,黔南州平均发病率高于全省平均水平,2010年后黔南、黔东南州,六盘水市平均增长速度均>0;≥61岁人群、农民发病率最高,分别为:270/10万、102.55/10万;男性发病率均高于女性(男:198.00/10万,女:108.34/10万);流动人口肺结核患者构成比在20.3%~24.6%之间,总体呈增长趋势(χ2趋势= 131.47,P<0.01);PTB/HIV共感染率在0.11%~0.36%之间。结论 贵州省肺结核发病率仍处较高水平,男性、≥61岁、农民、流动人口为重点人群,建议加强宣传教育,建立有效流动人口管理模式,尤其发病率较高、呈上升趋势区域,完善肺结核中HIV高危人群筛查制度。  相似文献   
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