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IntroductionAnti-thymocyte globulin (ATG) is used prior to allogeneic hematopoietic stem cell transplantation (allo-HSCT) for graft-versus-host disease (GVHD) prophylaxis. Two different ATG doses (7.5 or 10 mg/kg) were evaluated in comparison with a group without ATG therapy.MethodsWe retrospectively analyzed 132 patients who were transplanted with HSCT without ATG (non-ATG), or who received 7.5 mg/kg ATG (ATG-7.5) or 10 mg/kg ATG (ATG-10) prior to transplantation. The immune cells (CD3+CD4+ T cells, CD3+CD8+ T cells, CD19+ B cells and CD16+CD56+ NK cells) were examined in peripheral blood every three months post-HSCT for 12 months.ResultsCompared with non-ATG group, combined ATG-7.5/ATG-10 groups had significantly lower CD3+CD4+ T cells and higher CD3+CD8+ T cells at 3, 6, 9, 12 months post-HSCT; thus, displaying a lower CD4/CD8 ratio in the ATG groups compared to non-ATG group. The ratio of CD19+ B cells was statistically lower (at 3rd month, p = .014; at 6th month, p = .025) in combined ATG-7.5/ATG-10 groups at 3 and 6 months post-HSCT, but not at 9 and 12 months after HSCT. The ratios of CD3+CD4+ T cells, CD3+CD8+ T cells, CD19+ B cells and CD16+CD56+ NK cells were similar between the ATG-7.5 and ATG-10 groups at all examined time points. The overall survival (OS), progression-free survival (PFS), relapse and acute GVHD (aGVHD) were comparable among recipients without ATG therapy and with ATG-7.5 or/and ATG-10 therapies. Multivariate analysis revealed that immune cells ratios were not independent factors affecting prognosis.ConclusionThe ATG therapy at higher and lower doses led to a delayed reconstitution of T cells and the inversion of CD4/CD8 ratio for at least one year after HSCT. 相似文献
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ZHANG Guang-Qin HAO Xue-Mei DAI De-Zai FU Yu ZHOU Pei-Ai WU Cai-Hong Research Division of Pharmacology China Pharmaceutical University Nanjing China ~National Laboratorv of Biomembrane Membrane Biotechnology College of Life Sciences Peking University Beijing China 《Acta pharmacologica Sinica》2003,(12)
AIM: To study the effect of puerarin (Pue) on Na~+ channel in rat ventricular myocytes. METHODS: Whole-cell patch-clamp technique was applied on isolated cardiomyocytes from rats. RESULTS: Pue inhibited cardiac I_(Na) in a positive rate-dependent and dose-dependent manner, with an IC_(50) of 349 μmol/L. The kinetics of blockage of cardiac sodium channel by Pue resembled the ClassIa/Ic of antiarrhythmic agents. Pue 300 μmol/L did not alter the shape of the I-V curve of I_(Na), but markedly shifted the steady-state inactivation curve of I_(Na) towards more negative potential by 15.9 mV, and postponed the recovery of I_(Na) inactivation state from (21.9±1.6) ms to (54.4±3.4) ms (P<0.01 ). It demonstrated that the steady state of inactivation was affected by Pue significantly. CONCLUSION: Pue protected ventricular myocytes against cardiac damage and arrhythmias by inhibiting recovery from inactivation of cardiac Na~+ channels. 相似文献
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Glutamate-containing dipeptides do not modulate ligand binding at excitatory amino acid receptors 总被引:1,自引:0,他引:1
Dipeptides of the structure X-Glu (e.g. X = Phe, Leu) have been proposed as allosteric modulators of excitatory amino acid receptors in rat brain membranes. Here we report that these dipeptides reduce the binding of L-[3H]Glu (predominantly N-methyl-D-aspartate-sensitive sites) and of [3H]kainate to postsynaptic density preparations isolated from rat brain. However, several observations indicate that the effects of these dipeptides are mediated not by allosteric modulation, but by free L-Glu liberated by the actions of a membrane-associated aminopeptidase. The absolute and relative potencies of the dipeptides are similar at all acidic amino acid binding sites examined to date, suggesting the involvement of a factor with similar activity at each site (e.g. L-Glu). N-Acetyl-Met-Glu is a weak inhibitor of L-Glu and kainate binding, and N-blocked peptides are known to be poor substrates of aminopeptidases. Bestatin, an inhibitor of aminopeptidases, decreases or abolishes the effects of substrate dipeptides on L-Glu and kainate receptor binding, while having no effect itself. 相似文献
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Carbon dioxide (CO2) is generally unavoidable during the production of fuel gases such as hydrogen (H2) from steam reformation and syngas composed of carbon monoxide (CO) and hydrogen (H2). Efficient separation of CO2 from these gases is highly important to improve the energetic utilization efficiency and prevent poisoning during specific applications. Metal–organic frameworks (MOFs), featuring ordered porous frameworks, high surface areas and tunable pore structures, are emerging porous materials utilized as solid adsorbents for efficient CO2 capture and separation. Furthermore, the construction of hierarchical MOFs with micropores and mesopores could further promote the dynamic separation processes, accelerating the diffusion of gas flow and exposing more adsorptive pore surface. Herein, we report a simple, efficient, one-pot template-mediated strategy to fabricate a hierarchically porous CuBTC (CuBTC-Water, BTC = 1,3,5-benzenetricarboxylate) for CO2 separation, which demonstrates abundant mesopores and the superb dynamic separation ability of CO2/N2. Therefore, CuBTC-Water demonstrated a CO2 uptake of 180.529 cm3 g−1 at 273 K and 1 bar, and 94.147 cm3 g−1 at 298 K and 1 bar, with selectivity for CO2/N2 mixtures as high as 56.547 at 273 K, much higher than microporous CuBTC. This work opens up a novel avenue to facilely fabricate hierarchically porous MOFs through one-pot synthesis for efficient dynamic CO2 separation. 相似文献
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目的对3种乳癌手术麻醉方法进行比较,以选择合理的麻醉方法。方法对800例乳癌手术病人的三种麻醉的方法、麻醉选择、麻醉并发症、麻醉注意事项等进行了分析总结。结果硬膜外阻滞麻醉(EPA)穿刺成功226例(98.15%),阻滞效果满意208例(90.04%),出现轻度并发症4例;静脉吸入复合麻醉(VICA)气管插管成功率100%,95例(20.43%)气管内插管时心血管反应较显著;全身静脉麻醉(TIA)94例(90.38%)心血管反应较显著,62例(59.62%)术中舌根后坠需置咽喉通气道或托起下颌维持呼吸道通畅。结论EPA、VICA发生并发症少于TIA,乳癌手术麻醉应选择EPA、VICA,TIA慎用。 相似文献
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Anindita Dutta Sanghita Roychoudhury Saswati Chowdhury Manas Ranjan Ray 《International journal of hygiene and environmental health》2013,216(3):301-308
To perform sputum analysis for verification of pulmonary changes in premenopausal rural Indian women chronically exposed to biomass smoke during cooking.Three consecutive morning sputum samples were collected from 196 women (median age 34 years) cooking with biomass and 149 age-matched control women cooking with cleaner fuel liquefied petroleum gas. Smears made on slides were stained with Papanicolaou and Perl's Prussian blue. Airway oxidative stress was estimated as reactive oxygen species (ROS) generation (by flow cytometry) and superoxide dismutase (SOD) level (by spectrophotometry) in sputum cells. Airway inflammation was measured as sputum levels of interleukin (IL)-6, -8 and tumor necrosis factor- alpha (TNF-α). Particulate matter of diameter less than 10 (PM10) was measured using laser photometer while benzene exposure was monitored by measuring trans, trans-muconic acid (t,t-MA) in urine by HPLC-UV. Compared with control, sputum of biomass users contained more neutrophils, lymphocytes, eosinophils, alveolar macrophages, and showed presence of ciliocytophthoria, Charcot-Leyden crystals, Curschmann's spiral. ROS generation was increased by 2-fold while SOD was depleted by 31% in biomass users. They also had higher sputum levels of IL-6, -8 and TNF-α. Levels of PM10 and t,t-MA were 2.9- and 5.8-times higher in biomass-using women. PM10 and t,t-MA levels were positively associated with cellular changes in the sputum, markers of airway inflammation, and oxidative stress. Cooking with biomass alters sputum cytology, and increases airway inflammation and oxidative stress that might result in further amplification of the tissue damaging cascade in women chronically exposed to biomass smoke. 相似文献