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《Trends in Anaesthesia and Critical Care》2015,5(5):141-145
Background and objectiveSub-Tenon's blocks (STB) provide effective operating conditions for ophthalmic surgery. Originally performed by surgeons STB are now increasingly administered by anaesthetists in the UK. STB requires expertise in handling surgical instruments. The traditional way of gaining expertise used to be by practicing on the patients, this is no longer advisable, or desirable.Materials and methodsThis article describes an animal eye model, equipment and teaching process for STB that the author has set up in a wet lab setting at Birmingham and Midland Eye Centre. Advantages and disadvantages of other methods of animal and non animal simulation are discussed.ResultsThe trainees acquire bi-manual dexterity and develop confidence through hands-on practice on the animal eye before proceeding to perform the procedure on the patients.ConclusionThe isolated pig eye animal model is a practical, inexpensive and reproducible method of teaching novice trainees in performing sub-Tenon blocks. The training is the first of its kind in the UK, and is highly successful. 相似文献
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Andrea Bianchi Sandrine Dufort Pierre‐Yves Fortin François Lux Gérard Raffard Nawal Tassali Olivier Tillement Jean‐Luc Coll Yannick Crémillieux 《NMR in biomedicine》2014,27(8):971-979
One of the main reasons for the dismal prognosis of lung cancer is related to the late diagnosis of this pathology. In this study, we evaluated the potential of optimized lung MRI techniques as a completely non‐invasive approach for non‐small‐cell lung cancer (NSCLC) MRI in vivo detection and follow‐up in a mouse model of lung adenocarcinoma expressing the luciferase gene. Bioluminescent lung tumour cells were orthotopically implanted in immuno‐deficient mice. Ultra‐short echo‐time (UTE) MRI free‐breathing acquisitions were compared with standard gradient‐echo lung MRI (FLASH) using both respiratory‐gated and free‐breathing protocols. The MRI findings were validated against bioluminescence imaging (BLI) and gold‐standard histopathology analysis. Adenocarcinoma‐like pathological tissue was successfully identified in all the mice with gated‐FLASH and non‐gated UTE MRI, and good tumour co‐localization was found between MRI, BLI and histological analyses. An excellent or good correlation was found between the measured bioluminescent signal and the total tumour volumes quantified with UTE MRI or gated‐FLASH MRI, respectively. No significant correlation was found when the tumours were segmented on non‐gated MR FLASH images. MRI was shown to be a powerful imaging tool able to detect, quantify and longitudinally monitor the development of sub‐millimetric NSCLCs. To our knowledge, this is the first study which proves the feasibility of a completely non‐invasive MRI quantitative detection of lung adenocarcinoma in freely breathing mice. The absence of ionizing radiation and the high‐resolution of MRI, along with the complete non‐invasiveness and good reproducibility of the proposed non‐gated protocol, make this imaging tool ideal for direct translational applications. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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为了探讨以蒸散发为基础的作物需水量情况,便于为农业生产提供数据支持,利用风云三号、风云二号气象卫星数据,结合自动站气象数据,基于改进的SEBS模型对山西省进行作物需水量研究。结果表明:通过与实测数据对比验证发现模型结果精度较高。山西省2012年3—9月全省日均作物需水量最大值出现在春季的5月份,为1.27 mm,其中,以单季作物为代表的晋东北和中西部日均作物需水量最大值均出现在5月,分别为1.05 mm和1.38 mm;以双季作物为代表的晋东南日均作物需水量最大值出现在5月和7月,分别为1.28 mm和1.23 mm。可见山西省作物需水量普遍以春季最大,其中尤以中西部突出,晋东北则相对最低。 相似文献
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Xia-Ying Kuang Li Chen Zhi-Jie Zhang Yi-Rong Liu Yi-Zi Zheng Hong Ling Feng Qiao Shan Li Xin Hu Zhi-Ming Shao 《Oncotarget》2015,6(26):22227-22238
Currently, Stathmin1 (STMN1) and phospho-STMN1 levels in breast cancers and their clinical implications are unknown. We examined the expression of STMN1 and its serine phospho-site (Ser16, Ser25, Ser38, and Ser63) status by immunohistochemistry. Using Cox regression analysis, a STMN1 expression signature and phosphorylation profile plus clinicopathological characteristics (STMN1-E/P/C) was developed in the training set (n = 204) and applied to the validation set (n = 106). This tool enabled us to separate breast cancer patients into high- and low-risk groups with significantly different disease-free survival (DFS) rates (P < 0.001). Importantly, this STMN1-E/P/C model had a greater prognostic value than the traditional TNM classifier, especially in luminal subtype breast cancer (P = 0.002). Further analysis showed that patients in the low-risk group would benefit more from adjuvant paclitaxel-based chemotherapy (P = 0.002). In conclusion, the STMN1-E/P/C signature is a reliable prognostic indicator for luminal subtype breast cancer and may predict the therapeutic response to paclitaxel-based treatments, potentially facilitating individualized management. 相似文献
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Mehreteab Aregay Andrew B. Lawson Christel Faes Russell S. Kirby Rachel Carroll Kevin Watjou 《AIMS Public Health》2015,2(4):667-680
Low birth weight (LBW) is an important public health issue in the US as well as worldwide. The two main causes of LBW are premature birth and fetal growth restriction. Socio-economic status, as measured by family income has been correlated with LBW incidence at both the individual and population levels. In this paper, we investigate the impact of household income on LBW incidence at different geographical levels. To show this, we choose to examine LBW incidences collected from the state of Georgia, in the US, at both the county and public health (PH) district. The data at the PH district are an aggregation of the data at the county level nested within the PH district. A spatial scaling effect is induced during data aggregation from the county to the PH level. To address the scaling effect issue, we applied a shared multiscale model that jointly models the data at two levels via a shared correlated random effect. To assess the benefit of using the shared multiscale model, we compare it with an independent multiscale model which ignores the scale effect. Applying the shared multiscale model for the Georgia LBW incidence, we have found that income has a negative impact at both the county and PH levels. On the other hand, the independent multiscale model shows that income has a negative impact only at the county level. Hence, if the scale effect is not properly accommodated in the model, a different interpretation of the findings could result. 相似文献
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《Artificial intelligence in medicine》2014,60(1):41-51
ObjectiveThis article presents a model of a dengue and severe dengue epidemic in Colombia based on the cases reported between 1995 and 2011.MethodologyWe present a methodological approach that combines multiresolution analysis and fuzzy systems to represent cases of dengue and severe dengue in Colombia. The performance of this proposal was compared with that obtained by applying traditional fuzzy modeling techniques on the same data set. This comparison was obtained by two performance measures that evaluate the similarity between the original data and the approximate signal: the mean square error and the variance accounted for. Finally, the predictive ability of the proposed technique was evaluated to forecast the number of dengue and severe dengue cases in a horizon of three years (2012–2015). These estimates were validated with a data set that was not included into the training stage of the model.ResultsThe proposed technique allowed the creation of a model that adequately represented the dynamic of a dengue and severe dengue epidemic in Colombia. This technique achieves a significantly superior performance to that obtained with traditional fuzzy modeling techniques: the similarity between the original data and the approximate signal increases from 21.13% to 90.06% and from 18.90% to 76.83% in the case of dengue and severe dengue, respectively. Finally, the developed models generate plausible predictions that resemble validation data. The difference between the cumulative cases reported from January 2012 until July 2013 and those predicted by the model for the same period was 24.99% for dengue and only 4.22% for severe dengue.ConclusionsThe fuzzy model identification technique based on multiresolution analysis produced a proper representation of dengue and severe dengue cases for Colombia despite the complexity and uncertainty that characterize this biological system. Additionally, the obtained models generate plausible predictions that can be used by surveillance authorities to support decision-making oriented to designing and developing control strategies. 相似文献
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