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1.
目的 观察超声引导下微波消融(MWA)治疗胆肠吻合术(BEA)后肝脏恶性肿瘤术前肠道准备及应用抗生素对降低术后并发症及其严重程度的价值。方法 回顾性分析31例接受超声引导下MWA的BEA后肝脏恶性肿瘤患者,其中17例MWA前接受(A组)、14例(B组)未接受肠道准备及应用抗生素,对比观察2组术后并发症发生率及严重程度。结果 2组患者基线特征及原发肿瘤类型差异均无统计学意义(P均>0.05)。31例均顺利完成MWA。MWA后A组住院时间、发热率、发热持续时间、菌血症发生率及肝脓肿发生率均低于B组(P均<0.05)。结论 MWA治疗BEA后肝脏恶性肿瘤患者术前肠道准备及合理应用抗生素可明显降低术后并发症发生率及严重程度。  相似文献   
2.
目的: 利用Kalman滤波-紫外分光光度法考察微波提取动力学特征, 并对其进行可视化表征。方法: 利用Kalman滤波-紫外分光光度法对微波加热的三七物质组进行提取动力学研究并与传统加热方法进行对比, 测定2组物质组提取率, 通过Matlab软件建立物质组释放及释放增量图谱, 以期能定量、整体、可视化地评价不同加热方式的物质组提取动力学特征。结果: 以三七中所有化合物为整体物质组, 对2条提取动力学曲线进行f2相似因子拟合, f2=30.002 6(<50), 因此2条释放曲线存在显著差异; 2种加热方式提取动力学均符合一级动力学模型, 说明组分释放相对同步; 微波加热物质组在180 min时提取率达到80%以上, 传统加热提取率为45%左右, 释放量显著增加。结论: 采用Kalman滤波-紫外分光光度法评价微波加热物质组提取动力学特征, 满足实验要求; 可视化评价可以直接表达出微波提取动力学特征及同步性, 微波加热使物质组释放增量显著增加, 为后期微波提取技术的工业化生产提供理论参考。  相似文献   
3.
PurposeTo evaluate the efficacy and safety of microwave (MW) ablation as first-line locoregional therapy (LRT) for bridging patients with hepatocellular carcinoma (HCC) to liver transplant.Materials and MethodsThis retrospective study evaluated 88 patients who received percutaneous MW ablation for 141 tumors as first-line LRT for HCC and who were listed for liver transplantation at a single medical center between 2011 and 2019. The overall survival (OS) rate statuses after liver transplant, waitlist retention, and disease progression were evaluated using the Kaplan-Meier techniques.ResultsAmong the 88 patients (72 men and 16 women; mean age, 60 years; Model for End-Stage Liver Disease score, 11.2) who were listed for transplant, the median waitlist time was 9.4 months (interquartile range, 5.5–18.9). Seventy-one (80.7%) patients received transplant after a median waitlist time of 8.5 months. Seventeen (19.3%) patients were removed from the waitlist; of these, 4 (4.5%) were removed because of tumors outside of the Milan criteria (HCC-specific dropout). No difference in tumor size or alpha-fetoprotein was observed in the transplanted versus nontransplanted patients at the time of ablation (2.1 vs 2.1 cm and 34.4 vs 34.7 ng/mL for transplanted vs nontransplanted, respectively; P > .05). Five (5.1%) of the 88 patients experienced adverse events after ablation; however, they all recovered. There were no cases of tract seeding. The local tumor progression (LTP) rate was 7.2%. The OS status after liver transplant at 5 years was 76.7%, and the disease-specific survival after LTP was 89.6%, with a median follow-up of 61 months for all patients.ConclusionsMW ablation appears to be safe and effective for bridging patients with HCC to liver transplant without waitlist removal from seeding, adverse events, or LTP.  相似文献   
4.
BackgroundThe diatom test method using sodium hypochlorite (NaClO) was equivalent to the conventional method in water samples. However, the method using NaClO was inferior to the conventional method in lung samples, in which ethanol was used and the reaction with NaClO was longer compared with the method in water samples. Using water samples, we aimed to clarify whether these differences affect the diatom test result.Materials and methodsThirteen water samples from natural water sources were each divided into four parts corresponding to four (2 × 2) digestion methods: 3 “digestion” vs. 1 “digestion” and with ethanol vs. without ethanol. After the base-2 logarithmic transformation, the diatom counts were analyzed using three-way analysis of variance (ANOVA); factor 1 was “digestion times,” factor 2 was “ethanol,” and factor 3 was “sample number,” and the interaction between factors 1 and 2 was also analyzed.ResultsThe geometric means of the diatoms from the 3 “digestion” with ethanol method, the 3 “digestion” without ethanol method, the 1 “digestion” with ethanol method, and the 1 “digestion” without ethanol method were 373.5, 551.8, 436.6, and 522.0, respectively. ANOVA showed a significant difference in factor 2 (P = 1.7 × 10-4). There was no significant difference in factor 1 (P = 0.46), and no significant interaction between factors 1 and 2 (P = 0.13).ConclusionEthanol may decrease the diatom count in the diatom test using NaClO. In contrast, the diatom frustules do not dissolve through three-times digestion using NaClO.  相似文献   
5.
The degradation of organic pollutants in wastewaters assisted by oxide semiconductor nanostructures has been the focus of many research groups over the last decades, along with the synthesis of these nanomaterials by simple, eco-friendly, fast, and cost-effective processes. In this work, porous zinc oxide (ZnO) nanostructures were successfully synthesized via a microwave hydrothermal process. A layered zinc hydroxide carbonate (LZHC) precursor was obtained after 15 min of synthesis and submitted to different calcination temperatures to convert it into porous ZnO nanostructures. The influence of the calcination temperature (300, 500, and 700 °C) on the morphological, structural, and optical properties of the ZnO nanostructureswas investigated. All ZnO samples were tested as photocatalysts in the degradation of rhodamine B (RhB) under UV irradiation and natural sunlight. All samples showed enhanced photocatalytic activity under both light sources, with RhB being practically degraded within 60 min in both situations. The porous ZnO obtained at 700 °C showed the greatest photocatalytic activity due to its high crystallinity, with a degradation rate of 0.091 and 0.084 min−1 for UV light and sunlight, respectively. These results are a very important step towards the use of oxide semiconductors in the degradation of water pollutants mediated by natural sunlight.  相似文献   
6.
目的:建立黄连中39种无机元素的含量分析方法,为黄连后续的相关研究提供参考。方法:采用微波高压消解法对样品进行消解,采用电感耦合等离子体质谱法(ICP-MS)对样品中39种无机元素的含量进行检测,并对检测方法进行方法学考察。结果:分析方法符合测定要求,67批次样品中K、Mg、Mn、Zn、Fe 5种元素的平均含量最高,稀土元素的含量则普遍较低。各产地黄连在遗传距离为10时,表现出了较好的产地聚集性特征。结论:该方法操作简便、快速、准确,结果可靠,适用于黄连中无机元素的含量分析。  相似文献   
7.
This research work aims at investigating the influence of a fixed content of silicon nitride (Si3N4) and varied contents of graphene nanoplatelets (GNPs) on the physical (density, structural, morphological) and mechanical properties (microhardness, nanoindentation) of Al-Si3N4-GNPs composites. The composites were fabricated by a microwave-assisted powder metallurgy route. The Si3N4 concentration was fixed at (5 wt.%) in Al-Si3N4-GNPs composites while the GNPs concentration was varied between (0 wt.%) to (1.5 wt.%) with an increment of (0.5 wt.%). The structural analysis indicates the formation of phase pure materials with high crystallinity. The microstructural analysis confirmed the presence of the Si3N4 and GNPs showing enhanced agglomeration with the increasing amount of GNPs. Moreover, the surface roughness of the synthesized composites increases with an increasing amount of GNPs reaching its maximum value (RMS = 65.32 nm) at 1.5 wt.% of GNPs. The Al-Si3N4-GNPs composites exhibit improved microhardness and promising load-indentation behavior during nanoindentation when compared to pure aluminum (Al). Moreover, Al-Si3N4-GNPs composites demonstrate higher values of compressive yield strength (CYS) and ultimate compressive strength (UCS) when compared to pure Al despite showing a declining trend with an increasing amount of GNPs in the matrix. Finally, a shear mode of fracture is prevalent in Al-Si3N4-GNPs composites under compression loading.  相似文献   
8.
基于中医学整体观念,运用取象比类的方法,借自然界"川""海"之象进一步阐释"六经"之经与腑的双重含义,以及"肠胃为海"在气血化生、津液输布、糟粕传化、扶正培本方面的内涵.指出"六经"与"肠胃"在生理上彼此依存、病理上相互影响.在现代肠道研究中,肠道消化吸收营养物质、排泄代谢废物,体现了肠胃为"气血生化之海""津液输布之海""糟粕传化之海".肠道菌群促进肠黏膜免疫系统的发育并参与调节机体免疫,体现了肠胃为"扶正培本之海".肠神经系统与内分泌系统通过脑-肠轴的双向调控,如同六经与肠胃之间的海川循环,彼此依存、生生不息.通过探析"六经为川,肠胃为海"在肠道各功能网络中的内涵,揭示象思维在中西医整合医学发展中的重要作用,为挖掘经典及科研创新开辟思路.  相似文献   
9.
目的探究山药多糖对低强度连续微波辐射致小鼠免疫系统功能损伤的保护作用。方法将ICR雄性小鼠随机分为5组,即空白对照组、辐射损伤组及山药多糖低、中、高剂量组(200、400、800 mg/kg)。除空白对照组外,对其余各组小鼠施行10 mW/cm~2、5 min/d、连续30 d的微波辐照,建立低强度连续微波辐射损伤小鼠模型。自辐射的21 d起,各组小鼠分别给予以下处理:山药多糖低、中、高剂量组小鼠按照200、400、800 mg/kg的剂量灌胃给药,空白对照组与辐射损伤组给予等体积蒸馏水,各组均连续干预10 d。分别检测细胞免疫和体液免疫的相关指标,包括胸腺指数、脾脏指数、巨噬细胞吞噬指数、T淋巴细胞增殖率以及血清IgG、IL-4的含量。结果与空白对照组比较,辐射损伤组小鼠脾脏指数、腹腔巨噬细胞吞噬指数、T淋巴细胞增殖刺激指数及血清IgG含量下降,血清IL-4水平升高,差异有统计学意义(P0.05,P0.01)。与辐射损伤组比较,山药多糖不同剂量组可提高微波辐射损伤小鼠的巨噬细胞吞噬指数,T淋巴细胞增殖的刺激指数及血清IgG水平,降低血清IL-4水平(P0.05,P0.01)。结论山药多糖对低强度连续微波辐射引起的小鼠免疫系统功能损伤有明显改善作用。  相似文献   
10.
目的 评价三维可视化辅助经皮微波消融治疗复发性肝癌的临床效果。方法 选择2017-12-01至2019-06-01中国人民解放军总医院介入超声科连续收治的经皮微波消融的84例复发性肝癌病人,根据是否进行三维可视化评估分为三维重建组(30例,49个病灶)和常规组(54例,111个病灶)。比较两组病人治疗相关指标及预后情况。用三维可视化软件计算术前全肝体积、肿瘤体积、预计消融体积、术后全肝体积、消融体积,并对比术前规划消融体积与术后实际消融体积。结果 所有病人均完成经皮微波消融治疗,肿瘤最大径为(4.3±1.0)cm。随访时间为10(2~19)个月。三维重建组和常规组严重并发症发生率(6.7% vs. 9.3%)、总存活率(100% vs. 94.4%)、肝内复发率(8.2% vs. 12.6%)及局部复发率(6.1% vs. 10.8%)差异无统计学意义(P>0.05)。三维重建组病人术前规划体积和消融体积差异无统计学意义(P=0.616),消融后剩余肝体积与标准肝体积的比值为98.0%±25.6%。两组病人微波消融前后的丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆红素、胆碱酯酶差异无统计学意义(P>0.05)。结论 三维可视化辅助经皮微波消融在复发性肝癌的精准治疗中有重要的价值。  相似文献   
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