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91.
In order to find out anti-platelet activating factor (PAF) from natural resources, Korean medicinal plants used for the treatments
of peripheral circulation disorders were tested for their possible protective effects on PAF-induced anaphylactic shock. From
the above screening, the methanol extract ofGentiana scabra showed a potent antagonistic activity against PAF. Water suspension of the extract was partitioned with CH2Cl2 and EtOAc, successively. The EtOAc fraction which showed the highest activity was chromatographed on silica gel to yield
6 fractions. From the fraction which showed higher PAF-antagonistic activity than the other fractions, compound1 was isolated by recrystallization. On the basis of spectral data, compound1 was identified as 2-hydroxy-3-methoxybenzoic acid glucose ester. The compound prevented the mice from the PAF-induced death
at a dose of 300 μg/mouse. 相似文献
92.
玉米油和猪油对大鼠血脂血糖代谢和脑脂褐质影响的比较研究 总被引:5,自引:0,他引:5
采用幼年SD雄性大鼠30只,体重150±20g,随机分成三组,每组10只:(1)基础饲料组:普通大鼠饲料;(2)猪油组:基础饲料中加入10%猪油和1.5%胆固醇;(3)玉米油组:在基础饲料中加入10%玉米油和1.5%胆固醇,饲养9周,比较玉米油和猪油对大鼠血脂血糖和脑脂褐质的不同影响。结果表明,玉米油组TC和LDL-C水平较猪油组低,虽然两组均高于基础饲料组。玉米油组的HDL-C比猪油升高不显著,但HDL-C/TC(%)增加,同时LDL-C/HDL-C比值下降。基础饲料组,猪油组和玉米油组的大鼠平均血清TG分别为1.28,1.21和1.45(mmol/L),各组之间的差别不显著。高脂饲料组动物的空腹血糖(SG)较基础饲料组高,但差别无统计学意义。三组不同饲料大鼠的脑脂褐质(LPF)含量测定结果显示:基础饲料组大鼠的LPF平均值12.9U/g蛋白质,而玉米油组和猪油组均明显升高,分别为28.3和28.8U/g蛋白质。在以血脂各项指标为自常量,大脑LPF含量为因变量的相关分析中发现,LPF与TC和LDL-C呈正相关,相关系数分别为0.691和0.547,P<0.01. 相似文献
93.
Abstract. Objectives. To evaluate lipids and lipoproteins as risk factors for coronary heart disease (CHD) in older men with non-insulin-dependent diabetes (NIDDM) or abnormal glucose tolerance compared with normoglycaemic men. Design. A prospective, population-based cohort study based on the lipoprotein examination (1970–72) of the Honolulu Heart Program. Follow-up was through to December 1988. Setting. Honolulu, Hawaii. Subjects. Japanese-American men, ages 51–72 at baseline: 2042 with 1 h glucose < 12.5 mmol l?1 (normal group); 376 on oral hypoglycaemic agents or with 1 h glucose ≥ 12.5 mmol l?1 after 50 g oral glucose challenge (abnormal glucose tolerance group). None had prevalent coronary heart disease (CHD) or stroke at baseline. Main outcome measures. Incident CHD: definite nonfatal myocardial infarction (MI) or fatal CHD. Results. There were 221 incident cases in the normal group, and 65 in the abnormal glucose tolerance group. Total and high-density lipoprotein (HDL) cholesterol were significant predictors of incident CHD in men with NIDDM or abnormal glucose tolerance after controlling for age, body-mass index, systolic blood pressure, pack-years of cigarettes and alcohol consumption (P < 0.05). Total, low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) cholesterol were significant predictors in normal men, and HDL cholesterol was of borderline significance. Conclusions. Abnormal lipids and lipoproteins are significant, independent predictors of CHD in subjects with NIDDM or abnormal glucose tolerance. Attention to lipid and lipoproteins as CHD risk factors should be part of clinical management of these patients. 相似文献
94.
Summary The effects of the and anomers of D-glucose on insulin release were studied in a rat model of non-insulin-dependent diabetes, which was induced by streptozotocin injection at 2 days of age. Glucose tolerance of the streptozotocin-treated rats at 8–10 weeks of age was mildly diabetic. Insulin release from the isolated perfused pancreas of the diabetic rats in response to 10 mmol/l -D-glucose was markedly impaired, while insulin response to 10 mmol/l -D-glucose in the diabetic pancreas was only slightly reduced as compared to that in the control pancreas. 相似文献
95.
目的:探讨体轴发育抑制因子(Axin1)调节骨骼肌葡萄糖转运蛋白4(GLUT4)蛋白表达的作用及其机制。方法:利用RNAi干扰的Axin1腺病毒(Ad-siAxin1)感染C2C12小鼠骨骼肌细胞敲低Axin1,荧光显微镜和MTS实验明确Ad-siAxin1最佳感染浓度和时间。分别用携带绿色荧光蛋白的腺病毒(Ad-GFP)、Ad-siAxin1、载体质粒(vector)和Axin1质粒转染C2C12小鼠骨骼肌细胞敲低或过表达Axin1蛋白,Western印迹检测Axin1、端锚聚合酶蛋白(TNKS)和GLUT4蛋白水平。结果:荧光显微镜和MTS实验结果显示,在C2C12小鼠骨骼肌细胞中Ad-siAxin1作用的最佳浓度和时间分别为160μL和48 h。Western印迹结果显示,与Ad-GFP组相比,Ad-siAxin1组中Axin1蛋白降低(t=6.746,P<0.01)。Ad-siAxin1组TNKS蛋白水平降低(t=4.019,P<0.05),GLUT4蛋白水平下调(t=3.248,P<0.05)。与vector组相比,转染Axin1质粒后,Axin1蛋白水平上... 相似文献
96.
背景 目标范围内时间(TIR)作为血糖管理的新指标,与短期血糖波动相关,是否与长期血糖变异性相关尚不清楚。目的 探讨老年男性2型糖尿病患者TIR与长期随访期间糖化血红蛋白(HbA1c)变异系数、HbA1c变异性评分(HVS)的关系。方法 选取2007年1月至2011年1月在解放军总医院第二医学中心住院行动态血糖监测(CGM)的老年男性2型糖尿病患者200例,根据患者基线TIR水平,将其分为TIR≥85%组(n=141)和TIR<85%组(n=59)。对受试者随访观察(12.5±1.1)年,比较两组长期随访期间HbA1c变异系数和HVS。采用Pearson相关、多元线性回归分析TIR与HbA1c变异系数、HVS的关系。结果 TIR<85%组患者的长期HbA1c变异系数[(9.7±3.8)%比(8.2±4.5)%,P=0.028)]、HVS[(48.7±20.4)分比(32.5±20.8)分,P<0.001)]均明显高于TIR≥85%组。Pearson相关分析结果... 相似文献
97.
背景 估算肾小球滤过率(eGFR)是反映慢性肾脏病严重程度的量化指标之一。研究表明糖尿病前期血糖升高可增加慢性肾脏病风险,但对eGFR直接影响报道较少。目的 探讨社区人群中空腹血糖(FPG)受损患者血糖水平对eGFR的影响。方法 选择2020年1—12月于南昌大学第二附属医院体检中心体检的人群,收集一般资料与临床资料(包括既往史、性别、年龄、体质指数、血压、尿酸、血脂、FPG、尿常规、血肌酐),经相应纳入标准与排除标准筛选,最终纳入28 601例受试者。根据FPG水平将受试者分为FPG升高组(5.6 mmol/L≤FPG<7.0mmol/L)、FPG正常组(3.9 mmol/L≤FPG<5.6 mmol/L),比较两组一般资料与临床资料。为明确FPG对e GFR影响,采用个案匹配控制对两组受试者进行多因素(性别、年龄、平均动脉压、尿酸、总胆固醇、体质指数)匹配,采用Mann-Whitney U秩和检验比较匹配后两组一般资料。采用Spearman秩相关检验分析FPG与eGFR在FPG升高组、FPG正常组及匹配后FPG升高组、FPG正常组间的相关性。结果 共获得FPG正常组患者... 相似文献
98.
目的 探讨阻塞性睡眠呼吸暂停(OSA)与甘油三酯葡萄糖(TyG)指数的相关性。方法 选取2021年1月—2022年12月中南大学湘雅二医院行睡眠呼吸监测的270例OSA患者。根据甘油三酯和空腹血糖计算TyG指数,根据TyG指数的三分位数将患者分为Q1组、Q2组、Q3组,根据睡眠呼吸暂停低通气指数(AHI)将患者分为轻度组、中度组、重度组。采用多元线性分析评估TyG指数与AHI之间的关系,有序Logistic回归分析TyG指数与OSA严重程度之间的关系。结果 TyG指数越高的患者AHI、体质量指数(BMI)、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、空腹血糖越高,而血清高密度脂蛋白胆固醇(HDL-C)水平则越低(P <0.05)。TyG指数越高的患者肥胖和糖尿病、冠心病比例越高,男性比例越高,年龄更低(P <0.05)。随着患者AHI的增加,TyG指数、BMI增加,TG、空腹血糖上升,最低血氧饱和度下降(P <0.05),OSA越严重的患者肥胖、高血压和冠心病比例越高(P <0.05)。Pearson相关性分析结果显示,TyG指数与AHI水平呈正相关(r =0.282,P <0.05)。多元线性回归分析结果显示,AHI(b =0.002)、BMI(b =0.017)、TG(b =0.361)、空腹血糖(b =0.109)和性别(b =0.083)是TyG的影响因素(P <0.05)。有序Logistic模型结果显示:轻度OSA[O^R=0.396(95% CI:0.207,0.757)]和中度OSA[O^R=0.281(95% CI:0.163,0.484)]患者的TyG等级较重度OSA低,说明OSA严重程度增加是TyG指数升高的影响因素。非肥胖患者[O^R=0.424(95% CI:0.253,0.710)]、不吸烟患者[O^R=0.506(95% CI:0.283,0.904)]、非糖尿病患者[O^R=0.268(95% CI:0.156,0.460)]、非冠心病患者[O^R=0.452(95% CI:0.253,0.807)]、女性[O^R=0.409(95% CI:0.221,0.760)]的TyG等级较低,故吸烟、肥胖、糖尿病、冠心病、男性是TyG指数升高的影响因素(P <0.05)。结论 TyG指数与OSA严重程度相关,可以考虑将TyG指数用于OSA患者胰岛素抵抗的观察,从而进行干预,使患者获益。 相似文献
99.
Changes in PG, PI and PFFA were examined and compared in fed rats or after 0 to 12 hours of fasting, during the night or during the day. At night, a progressive decrease in PG and PI and an increase in PFFA were induced by 0 to 12 hours of food deprivation. During the light period a decrease in PG occurred only from the 6th hour of fasting. A slight, progressive increase in PFFA levels was induced from 0 to 12 hours of fasting, while no significant variation of PI levels was observed. The results are discussed in terms of relationships between blood glucose, PFFA levels, and food intake in control rats over the circadian cycle. 相似文献
100.
To investigate the age-dependent functional importance of cholinergic neocortical inputs, and to explore whether cortical cholinergic denervation in aged animals might better model the cerebral metabolic changes of Alzheimer's disease, the effects of unilateral ablation of the nucleus basalis magnocellularis (NBM) on cerebral glucose metabolism were studied in young and aged rats. Regional cerebral metabolic rates for glucose (rCMRglc) were determined, using the [14C]deoxyglucose method, in 48 brain regions of 3- and 24-month old Fischer-344 rats at 3, 7, 14 and 28 days after stereotaxic injection of ibotenate into the right NBM, and in sham-operated animals at 3 and 14 days later. For both ages the peak effect of unilateral NBM ablation occurred 3 days later: in young rats, rCMRglc was significantly reduced (compared to the contralateral side) in all 24 anterior cortical areas examined (mean decline 20%), whereas in aged animals, only 9 of 24 areas showed a significant decline in glucose utilization, and the magnitude of rCMRglc reduction (9%) was smaller. Near complete recovery of rCMRglc occurred by 7 days in young and old rats. We conclude that the basalocortical cholinergic projection plays a smaller role in neocortical function of aged rats, possibly because its tonic activity is reduced. Both young and aged rats undergo cortical metabolic normalization after unilateral NBM ablation; hence the NBM-lesioned aged rat is not a better model of the progressive decline in rCMRglc that occurs in Alzheimer's disease. 相似文献