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101.
102.
Myeloma is a malignancy of the antibody-producing plasma cells and, as such, these cells synthesize large quantities of unfolded or misfolded immunoglobulin. The build-up of excess protein triggers a number of downstream signal transduction cascades, including endoplasmic reticulum stress and autophagy. As a result, myeloma cells are uniquely reliant on these and other protein handling pathways for their survival. Strategies aimed at targeting this vulnerability have proved successful with the proteasome inhibitor, bortezomib, already licensed for clinical use. In addition to the proteasome, various other points within the protein handling pathways are also the subject of drug discovery projects, with some already progressing into clinical trials. These include compounds directed against heat shock proteins, the unfolded protein response and pathways both upstream and downstream of the proteasome. More recently, the role of autophagy has been recognized in myeloma. In this review, we discuss the various pathways used by myeloma cells for survival, with particular emphasis on the emerging role and conundrum of autophagy, as well as highlighting pre-clinical research on novel inhibitors targeting protein handling pathways. 相似文献
103.
Caballero-Velázquez T Sánchez-Abarca LI Gutierrez-Cosio S Blanco B Calderon C Herrero C Carrancio S Serrano C Del Cañizo C San Miguel JF Pérez-Simón JA 《Haematologica》2012,97(9):1329-1337
Background We have previously shown that bortezomib induces a depletion of alloreactive T cells and allows the expansion of T cells with suppressive properties. In the current study, we analyzed the potential synergistic effect of bortezomib in conjunction with sirolimus in order to reduce-graft-versus-host disease without hampering graft-versus-leukemia effect in the allogeneic transplant setting. DESIGN AND METHODS: We evaluated the effect of sirolimus, bortezomib or the combination of both in the proliferation and activation of in vitro stimulated T lymphocytes. Pathways involved in this synergy were also analyzed using Western blot assays. Finally, BALB/c mice receiving C57BL/6 allogeneic donor bone marrow with splenocytes were used to measure in vivo the effect of this novel combination on the risk of graft-versus-host disease. RESULTS: The combination of both drugs synergistically inhibited both activation and proliferation of stimulated T cells. Also, the production of Th1 cytokines (IFN γ, IL-2 and TNF) was significantly inhibited. This effect was due, at least in part, to the inhibition of Erk and Akt phosphorylation. In vivo, the combination reduced the risk of graft-versus-host disease without hampering graft-versus-leukemia effect, as shown in mice receiving graft-versus-host disease prophylaxis with sirolimus plus bortezomib being infused with tumor WEHI cells plus C57BL/6 donor BM and splenocytes. Conclusions The current study reveals a synergistic effect of the combination sirolimus and bortezomib to prevent graft-versus-host disease while maintaining the graft-versus-leukemia effect. 相似文献
104.
Ping-ping LI ;Wei-ping WANG ;Zhi-hui LIU ;Shao-feng XU ;Wen-wen LU ;Ling WANG ;Xiao-liang WANG 《Acta pharmacologica Sinica》2014,35(7):869-878
Aim: Potassium 2-(1-hydroxypentyl)-benzoate (d/-PHPB) is a new drug candidate for ischemic stroke. The aim of this study was to investigate the effects of dI-PHPB on memory deficits and long-term potentiation (LTP) impairment in animal models of Alzheimer's disease. Methods: The expression of NMDA receptor subunits GluN1 and GluN2B in the hippocampus and cortex of APP/PS1 transgenic mice were detected using Western blot analysis. Memory deficits of the mice were evaluated with the passive avoidance test. LTP impairment was studied in the dentate region of Aβ1-42-injected rats and APP/PS1 transgenic mice. Results: APP/PS1 transgenic mice showed significantly lower levels of GluN1 and p-GluN2B in hippocampus, and chronic administration of dI-PHPB (100 mg·kg-1·d1, po) reversed the downregulation of p-GluN2B, but did not change GluN1 level in the hippocampus. Furthermore, chronic administration of d/-PHPB reversed the memory deficits in APP/PS1 transgenic mice. In the dentate region of normal rats, injection of dI-PHPB (100 μmol/L, icv) did not change the basal synaptic transmission, but significantly enhanced the high-frequency stimulation (HFS)-induced LTP, which was completely prevented by pre-injection of APV (150 μmol/L, icv). Chronic administration of dI-PHPB (100 mg·kg-1·d-1, po) reversed LTP impairment in Aβ1-42 -injected normal rats and APP/PS1 transgenic mice. Conclusion: Chronic administration of d/-PHPB improves learning and memory and promotes LTP in the animal models of Alzheimer's disease, possibly via increasing p-GluN2B expression in the hippocampus. 相似文献
105.
Chu J Sun Y Zhao Y Wei W Wang J Liu X Jia Y Mao K Pu J Zhang S 《Journal of cardiovascular electrophysiology》2012,23(8):840-845
Identification of the Slow Conduction Zone in a Macroreentry. Background: Although idiopathic left ventricular tachycardia (ILVT) has been shown to possess a slow conduction zone (SCZ), the details of the electrophysiological and anatomic aspects are still not well understood. Objective: We hypothesized that the SCZ can be identified using a 3‐dimensional electroanatomic (EA) mapping system. Methods : Ten patients with ILVT were mapped using a 3‐dimensional electroanatomic (EA) mapping system. After a 3‐dimensional endocardial geometry of the left ventricular was created, the conduction system with left Purkinje potential (PP) and the SCZ with diastolic potential (DP) in LV were mapped during sinus rhythm (SR) and ventricular tachycardia (VT) and were tagged as special landmarks in the geometry. The electrophysiological and anatomic aspects of it were investigated. Results: EA mapping during SR and VT was successfully performed in 7 patients, during VT in 3 patients. The SCZ with DPs located at the inferoposterior septum was found in 7 patients during SR and all patients during VT. The length of the SCZ was 25.2 ± 2.3 mm with conduction velocity 0.08 ± 0.01 m/s. No differences in these parameters were found between patients during SR and VT (P > 0.05). An area with PP was found within the posterior septum. A crossover junction area with DP and PP was found in 7 patients during SR and VT. This area with DP and PP during SR coincided or were in proximity to such area during VT and radiofrequency ablation targeting the site within the area abolished VT in all patients. Conclusion: The ILVT substrate within the junction area of the SCZ and the posterior fascicular can be identified and can be used to guide the ablation of ILVT. (J Cardiovasc Electrophysiol, Vol. 23, pp. 840‐845, August 2012) 相似文献
106.
107.
Breeding is not only an important area of medicinal plants research but also the foundation for the superior varieties acquirement of medicinal plants. The rise of modern biotechnology provides good opportunities and new means for medicinal plants breeding research in China. Biotechnology shows its technical advantages and new development prospects in breeding of new medicinal plants varieties with high and stable yield, good quality, as well as stress-resistance. In this paper, we describe recent advances, problems, and development prospects about the application of modern biotechnology in medicinal plants breeding research in China. 相似文献
108.
This pilot clinical trial tested effectiveness of a poetry writing intervention for family caregivers of elders with dementia. This paper presents findings from a larger study using mixed methods to examine outcome variables of self-transcendence, resilience, depressive symptoms, and subjective caregiver burden. Findings reported here focus on qualitative analysis of in-depth interviews conducted with participants following their poetry writing experience. A grounded theory approach was used. Themes that arose from the data support a mid-range theory of self-affirmation in caregivers with subthemes of achievement, catharsis, greater acceptance, empathy, self-awareness, reflection, creative and fun, positive challenge, and helping others. 相似文献
109.
幽门螺杆菌动力在胃黏膜定植中的机制研究 总被引:2,自引:0,他引:2
幽门螺杆菌能在人类的胃定植并且在胃内存活数十年甚至一生,幽门螺杆菌有很多潜在的致病因子使其定植在胃的特殊环境中.动力是必须的定植因子,依据于幽门螺杆菌无动力突变株不能感染无菌乳猪,动力不能作为定植因子是因为在活体胃腔内幽门螺杆菌的动力很快失去,幽门螺杆菌动力的作用尚未清楚.本文的目的 是探讨对定植与幽门螺杆菌动力之间的关系. 相似文献
110.
A comparative study of pharmacodynamics and clinical efficacy of nimodipine, nifedipine and foridon in ischemic stroke (late recovery and residual period) was performed in 97 patients with ischemic stroke. It was found that nimodipine, nifedipine and foridon at late recovery or residual stages significantly improved higher psychic functions, promoted regression of neurologic disorders and optimized social rehabilitation. Nimodipine, primarily, decreased the intensity of neurological disorders, improved higher psychic functions and had a positive impact on cerebral hemodynamics. Nifedipine primarily improved central hemodynamics (increased stroke output and ejection fraction). Foridon is most effective selective pharmacodynamic impact on peripheral hemodynamics (stimulated arteriolar blood flow, diminished venous capacity and spasticity), i.e. normalized peripheral blood flow. 相似文献