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101.
Huehnergarth KV Mozaffarian D Sullivan MD Crane BA Wilkinson CW Lawler RL McDonald GB Fishbein DP Levy WC 《The American journal of cardiology》2005,95(12):1492-1495
The usefulness of low relative lymphocyte count as an independent predictor of death/urgent transplant in patients with heart failure (HF) and the association between low relative lymphocyte count and neurohormone and cytokine activation were investigated. Relative lymphocyte count, clinical variables, neurohormones, and cytokines were measured in 129 outpatients with HF. Follow-up extended to a mean of 3.0 +/- 1.2 years for death/urgent transplant. Low relative lymphocyte count was independently associated with a 3.4-fold increased risk of death/urgent transplant. Relative lymphocyte count was positively associated with hemoglobin and inversely associated with age, jugular venous pressure, creatinine, leukocyte count, and soluble tumor necrosis factor receptor-1. There was only a borderline inverse association with cortisol levels during evening hours. 相似文献
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Microemboli detection and characterisation have recently received great attention due to its clinical importance in the management of cerebrovascular disease. The new method presented in this paper is directly based on the idea that the ultrasound (US) backscattered signal from flowing blood is chaotic (El-Brawany and Nassiri 2002). The detection technique involves building a nonlinear model of the deterministic characteristics of the chaotic backscatter signal from blood, and the use of this model to look at the prediction error as a primary decision-making criterion for the microemboli detector. A complementary feature to the prediction error, namely, the degree of coherence between the US excitation pulse and the prediction error signal is used to enhance the detection process. The detector has been built using a feed-forward neural network with error back-propagation. The detection technique is tested successfully using a vascular flow phantom with solid spheres and bubbles of known sizes introduced in the flow circuit to mimic solid and gaseous emboli. Receiver operating characteristic (ROC) curve is used to assess the performance of the detection process. The total classification rate ranges from 88% to 96%. 相似文献
104.
The ultrasound (US) scattered signal from blood has been treated as a random signal by many investigators. However, the degree of randomness of a medium is a relative term that can change considerably with the resolution of the sensor. In this study, the backscattered signal from blood has been looked at as a chaotic signal. By this treatment, according to Taken's theorem, a single variable (e.g., amplitude of the blood-backscattered signal) can be used to reconstruct the nonlinear dynamics of the blood-scattered signal. Multilayer perceptron neural network architecture, with error back-propagation, has been formulated and used as a basis for building and testing the chaotic model of the backscattered signal. This chaotic model is used successfully as a short-term predictor of the backscattered signal from blood-mimicking fluid (BMF) flowing in a vascular flow phantom under pulsatile flow. This modelling approach can be useful, for example, in detecting blood-borne emboli. 相似文献
105.
Permanent osteoblastic cell lines are potential tools to study the interactions between osteoblastic and hematopoietic cells in the bone marrow cavity. In a recent work we have shown that the osteosarcoma cell line CAL72 may be more closely related to normal osteoblasts than the osteosarcoma cells previously described. In the present work we continued the characterisation of the CAL72 cell line with regard to its effects on various hematopoietic cells, in coculture experiments. We show here that CAL72 cells, in contrast to MG-63 or SaOS-2 osteosarcoma cell lines, do not inhibit hematopoietic colony formation and sustain the limited expansion of hematopoietic progenitors in a similar way to that described for normal osteoblasts. We also demonstrate that CAL72 cells induce the monocytic differentiation of the promyelocytic HL-60 cell line like MG-63 and SaOS-2, but support a better maturation and a longer survival of the differentiated cells than the two other osteosarcoma cell lines. In order to better understand the differential effects observed between CAL72 and MG-63 or SaOS-2, we analysed the cytokine and chemokine mRNA expression of these cells using the RNase protection quantitative assay. We show here that the expression profile of CAL72 is clearly different from that of MG-63 or SaOS-2 and may explain, at least in part, its specific effects on hematopoietic cells. Taken together these experiments confirm that CAL72 has particular properties and is an interesting tool to study the role of osteoblastic cells in hematopoietic cell growth and differentiation. 相似文献
106.
Blech Michaela Melien Richard Tschammer Nuska Presser Beate Hinderberger Dariush Garidel Patrick 《Pharmaceutical research》2021,38(12):2065-2089
Pharmaceutical Research - Introduction of the activation energy (Ea) as a kinetic parameter to describe and discriminate monoclonal antibody (mAb) stability. Ea is derived from intrinsic... 相似文献
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Ghods AJ Nasrollahzadeh D 《Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation》2005,3(2):351-354
Currently, the buying and selling of kidneys through "transplant tourism" is occurring at an increasing rate, both in developed and developing countries. Since 1988, Iran has adopted a compensated and regulated living-unrelated donor renal transplant program, and by providing financial incentives to volunteer living donors, has eliminated the renal transplant waiting list. In the Iranian model of renal transplantation program, regulations have been put in place to prevent transplant tourism. Foreigners are not allowed to undergo renal transplantation from Iranian living-unrelated donors. They also are not permitted to volunteer as kidney donors for Iranian patients. A study at the transplant unit of Hashemi Nejad Kidney Hospital in Tehran, Iran, showed that of 1881 renal transplant recipients, 19 (1%) were Afghani or Iraqi refugees, 11 (0.6%) were other foreign nationals, and 18 (0.9%) were Iranian immigrants. Renal transplantations seemed ethically acceptable to all refugees and foreign nationals. However, transplantation of Iranian immigrants who had been residing abroad for years constituted true transplant tourism. 相似文献
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