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81.
目的 通过测定机械通气对急性呼吸窘迫综合征(Acute Respiratory Distress Syndrome,ARDS)患者支气管肺泡灌洗液(BronchoAlveolar Lavage Fluid,BALF)与血清中肺损伤标记物的变化,明确气道压力释放通气(Airway Pressure Release Ventilation,APRV)与小潮气量保护性通气(Low Tidal Volume Protective Ventilation,LTV)对ARDS患者呼吸机相关性肺损伤(Ventilator-Induced Lung Injury,VILI)的影响。方法 收集深圳大学总医院及海南省人民医院2018-01至2019-05内ARDS住院患者40例,以随机数字法分为两组:A组21例,B组19例,A组先予APRV通气24 h,随后转为LTV 24 h;B组先予LTV 24 h,再转为APRV 24 h,比较干预治疗0 h、24 h、48 h两组患者氧合指数、呼吸力学、BALF及血清中肺泡表面活性蛋白(Pulmonary Surfactant Protein D,SP-D)、重组...  相似文献   
82.
目的 评估躯体症状自我筛查问卷(SQSS)在中国普通居民中的效度和信度,分析功能躯 体症状检出阳性的受试者一般特征。方法 采用方便抽样法,于 2020 年 2— 3 月通过问卷星向中国居 民发送调查问卷,进行一般资料、SQSS、广泛性焦虑量表 -7(GAD-7)、9 项患者健康问卷(PHQ-9)和怀特 利指数 -7(WI-7)的施测。2 周后采用随机数字表法选取 100 名受试者进行 SQSS 的重测。采用条目得分 与量表总分的相关分析、极端组检验进行项目分析;采用探索性因素分析、验证性因素分析检验效度; 采用内部一致性 Cronbach''s α 系数、分半信度系数和重测相关系数检验信度;采用 χ2 检验、t检验比较 功能性躯体症状筛查阳性及阴性者的一般资料及临床资料。结果 共收集问卷 1 506 份,剔除无效问 卷 56 份,最终纳入 1 450 名(96.3%)受试者。SQSS 项目分析结果显示各条目得分与量表总分均呈正相关 (r=0.49~0.70,均P< 0.001),量表各条目区分度分析结果显示差异均有统计学意义(t=15.337~27.862, 均P< 0.001)。探索性因素分析示 SQSS 可分为 4 个维度,验证性因素分析示 SQSS 的 4 因子结构模型拟 合良好,卡方 / 自由度(χ2 /df)为 5.79,拟合优度系数(GFI)为 0.94,近似误差均方根(RMSEA)为 0.06,均 方根残差(RMR)为 0.03,比较拟合指数(CFI)为 0.93,规范拟合指数(NFI)为 0.92,不规范拟合指数(NNFI) 为 0.92,Tucker-Lewis 指数(TLI)为 0.92;SQSS 的 Cronbach''s α 系数为 0.92,分半信度系数为 0.90;SQSS 总 分和 WI-7、PHQ-9、GAD-7 得分均呈正相关(r=0.67、0.68、0.61;均P< 0.01)。以 SQSS 29 分为划界分,功 能性躯体症状在普通居民中的检出率为 10.28%(149/1 450)。功能性躯体症状检出阳性者中女性、有精 神疾病者、有慢性躯体疾病者占比更高(χ2 =5.12、29.90、34.08;均P< 0.05),检出阳性者的 SQSS、GAD- 7、PHQ-9、WI-7 得分高于阴性者(Z=20.03、14.51、13.03、15.27,均P< 0.001)。结论 SQSS 具有较好的 效度和信度,可用于在普通人群中进行功能性躯体症状的自我筛查。在中国普通居民中,功能性躯体 症状检出率较高。  相似文献   
83.
目的:制备促黄体激素释放激素类似物(Luteinizing hormone-releasing hormone analogues,LHRHa)靶向紫杉醇脂质体(Paclitaxel liposomes,PTX-Lipo),研究其在体外增强紫杉醇(Paclitaxel,PTX)对卵巢癌A2780/DDP细胞的抑制作用。方法:采用薄膜超声法制备PTX-Lipo与LHRHa靶向紫杉醇脂质体(LHRHa-Paclitaxel liposomes,LHRHa-PTX-Lipo),用透射电镜考察脂质体形态;高效液相色谱法测定2种PTX-Lipo的包封率;激光共聚焦法通过卵巢癌A2780/DDP细胞对4-氟-7-硝基-2,1,3-苯并氧杂恶二唑荧光素的摄取检测来反映细胞对NBD-Lipo与NBD-LHRHa-Lipo的摄取情况;MTT法及细胞克隆形成实验检测LHRHa-PTX-Lipo体外对卵巢癌细胞的生长抑制情况。结果:制备LHRHa-PTX-Lipo的平均粒径123.4 nm,包封率在90%以上;A2780/DDP细胞对NBD-LHRHa-Lipo组的荧光摄取明显高于NBD-Lipo组;LHRHa-PTX-Lipo对A2780/DDP细胞的生长及克隆形成抑制明显高于PTX组及PTX-Lipo组(P<0.05)。结论:采用薄膜超声法制备的LHRHa-PTX-Lipo可使药物在靶部位聚集,增强药物对卵巢癌细胞的抑制作用。  相似文献   
84.
ObjectivesTo compare the biomechanical performance of proximal femoral nail anti‐rotation (PFNA), the “upside‐down” less invasive plating system (LISS), and proximal femoral locking plate (PFLP) in fixing different fracture models of subtrochanteric fractures.MethodsThirty composite femurs were divided into three equal groups (PFNA, PFLP, and reverse LISS). The implant‐femur constructs were tested under axial compression load (0–1400 N) from models I to IV, which represented the Seinsheimer type I subtrochanteric fracture, type IIIa subtrochanteric fracture with the posteromedial fragment reduced; type IIIa subtrochanteric fracture with the posteromedial fragment lost; and type IV subtrochanteric fracture, respectively. Axial stiffness was analyzed for each group. Each group was then divided into two subgroups, one of which underwent torsional and axial compression failure testing, while the other subgroup underwent axial compression fatigue testing. The torsional stiffness, failure load, and cycles to failure were analyzed.ResultsPFNA had the highest axial stiffness (F = 761.265, p < 0.0001) and failure load (F = 48.801, p < 0.0001) in model IV. The axial stiffness and failure load of the PFLP were significantly higher than those of the LISS (p < 0.0001, p = 0.001). However, no significant difference in axial stiffness was found between models I to III (model I: F = 2.439, p = 0.106; model II: F = 2.745, p = 0.082; model III: F = 0.852, p = 0.438) or torsional stiffness in model IV (F = 1.784, p = 0.187). In fatigue testing, PFNA did not suffer from construct failure after 90,000 cycles of axial compression. PFLP and LISS were damaged within 14,000 cycles, although LISS withstood more cycles than PFLP (t = 3.328, p = 0.01).ConclusionThe axial stiffness of the three implants was similar in models I to III. The biomechanical properties of PFNA were the best of the three implants in terms of axial stiffness, failure load, and fatigue testing cycles in model IV. The axial stiffness and failure load of the PFLP were better than those of the reverse LISS, but PFLP had fewer cycles in the fatigue tests than the reverse LISS.  相似文献   
85.
Background:Vascular dementia (VaD) is a comprehensive syndrome related to the damage of cognitive function and various cerebral vascular illnesses. VaD is also generally recognized as the second most common type of dementia after Alzheimer disease, contributing to 30% of the dementia population in Asia and developing countries. The ability of donepezil hydrochloride and nimodipine had been respectively proven in improving cognitive function in vascular dementia. However, whether the combined application of both drugs contribute to better efficacy remains as a research hotspot. Studies had shown definite satisfactory result with such combination, however evidence-based evaluation of the efficacy is still lacking. Therefore, meta-analysis is employed in this study to evaluate the efficacy and safety of using donepezil hydrochloride combined with nimodipine in treating VaD to provide references for clinical treatments. The efficacy of donepezil hydrochloride combined with nimodipine on treating vascular dementia is systematically reviewed to provide evidence-based references for clinical applications.Methods:Both Chinese and English databases were searched from the start till August, 2020 for any RCT regarding the combined use of the 2 drugs in treating vascular dementia. Two investigators would later evaluate and screened out research and data based on an improved Jaded scale. Software Rev Man 5.3.0 was employed to carry out meta-analysis on clinical effificacy, mini-mental state examination (MMSE) ratings, activity of daily living (ADL) ratings, and clinical dementia scale (CDR) ratings.Results:Donepezil hydrochloride combined with nimodipine had demonstrated satisfactory efficacy on the treatment of vascular dementia. Improvements were namely spotted on MMSE scale, ADL scale, and CDR scale, with the utmost efficacy by 12 weeks after intervention.Conclusions:Donepezil hydrochloride combined with nimodipine had good efficacy in the treatment of patients with vascular dementia, mainly in terms of improving the Simple MMSE scores, the ability to use daily living scale (ADL) scores and the CDR, and the best results were obtained after 12 weeks of intervention. Such conclusion should be cautiously evaluated.  相似文献   
86.
患者男,61岁,因头枕部丘疹3年就诊。患者于3年前无明显诱因下发现枕部丘疹,无自觉症状,后缓慢增大。否认病程中出血、溃疡、脱屑等。体检:一般情况好,各系统检查未见异常。皮肤科检查:枕部见一枚黄豆大小丘疹,直径约9 mm,淡红色,境界清晰,表面光滑,质地坚实(图1A)……  相似文献   
87.
88.
There is a lack of studies on the association between whole grain intake and cardiometabolic risk factors in China and the current definition of whole grains is inconsistent. This study defined whole grains in two ways, Western versus traditional, and examined their associations with the risks of major cardiometabolic factors (CMFs) among 4706 Chinese adults aged ≥18 years, who participated in surveys both in 2011 and in 2015. Diet data were collected by consecutive 3 d 24 h recalls, together with household seasoning weighing. Whole grains were defined as grains with a ratio of fiber to carbohydrate of ≥0.1, while coarse grains were defined as grains except for rice and its products, and wheat and its products. Multivariable logistic regressions were modeled to analyze the associations of intakes of whole grains and coarse grains, respectively, with risks of major CMFs including obesity-, blood pressure-, blood glucose- and lipid-related factors, which were defined by International Diabetes Federation and AHA/NHLBI criteria. After adjusting for potential confounders, the odds of elevated LDL-C decreased with the increasing intake levels of whole grains (OR 0.64, 95% CI 0.46–0.88, p-trend < 0.05). Moreover, adults with the whole grain intake of 50.00 to 150.00 g/day had 27% lower odds of overweight and obesity (OR 0.73, 95% CI 0.54–0.99) and 31% lower odds of elevated LDL-C (OR 0.69, 95% CI 0.49–0.96), as compared with non-consumers. In conclusion, given the significant nutrient profiles of whole grains and coarse grains, the adults with higher intakes of whole grains only may have a lower risk of LDL-C and overweight and obesity.  相似文献   
89.
Porcine reproductive and respiratory syndrome virus (PRRSV) induces secretion of high mobility group box 1 (HMGB1) to mediate inflammatory response that is involved in the pulmonary injury of infected pigs. Our previous study indicates that protein kinase C-delta (PKC-delta) is essential for HMGB1 secretion in PRRSV-infected cells. However, the underlying mechanism in HMGB1 secretion induced by PRRSV infection is still unclear. Here, we discovered that the phosphorylation level of HMGB1 in threonine residues increased in PRRSV-infected cells. A site-directed mutagenesis study showed that HMGB1 phosphorylation at threonine-51 was associated with HMGB1 secretion induced by PRRSV infection. Co-immunoprecipitation (co-IP) of HMGB1 failed to precipitate PKC-delta, but interestingly, mass spectrometry analysis of the HMGB1 co-IP product showed that PRRSV infection enhanced HMGB1 binding to ribosomal protein S3 (RPS3), which has various extra-ribosomal functions. The silencing of RPS3 by siRNA blocked HMGB1 secretion induced by PRRSV infection. Moreover, the phosphorylation of HMGB1 at threonine-51 was correlated with the interaction between HMGB1 and RPS3. In vivo, PRRSV infection also increased RPS3 levels and nuclear accumulation in pulmonary alveolar macrophages. These results demonstrate that PRRSV may induce HMGB1 phosphorylation at threonine-51 and increase its interaction with RPS3 to enhance HMGB1 secretion. This finding provides insights into the pathogenesis of PRRSV infection.  相似文献   
90.
Phage therapy is a promising biocontrol management on plant diseases caused by bacterial pathogens due to its specificity, efficiency and environmental friendliness. The emergence of natural phage-resistant bacteria hinders the application of phage therapy. Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of the devastating bacterial leaf blight disease of rice. Here, we obtained a spontaneous mutant C2R of an Xoo strain C2 showing strong resistance to the lytic phage X2. Analysis of the C2R genome found that the CDS2289 gene encoding glycosyltransferase acquired a frameshift mutation at the 180th nucleotide site, which also leads to a premature stop mutation at the 142nd amino acid. This mutation confers the inhibition of phage adsorption through the changes in lipopolysaccharide production and structure and bacterial surface morphology. Interestingly, glycosyltransferase-deficient C2R and an insertional mutant k2289 also showed reduced virulence, suggesting the trade-off costs of phage resistance. In summary, this study highlights the role of glycosyltransferase in interactions among pathogenic bacteria, phages and plant hosts, which provide insights into balanced coevolution from environmental perspectives.  相似文献   
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