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981.
目的:肝脏可溶性复合物具有保护肝脏、刺激肝组织再生等生物学活性,观察天然物质肝脏可溶性复合物对肿瘤细胞生长增殖的抑制作用.方法:实验于2006-05/2007-02在四川大学华西医院生物治疗国家重点实验室实验肿瘤研究室完成.①分离人胚胎、成年及新生小鼠肝脏组织,生理盐水清洗、剪碎、筛网过滤,用生理盐水制备混悬液,3 000 r/min离心,收集上清,制备肝脏可溶性复合物.②体外实验:用上述不同来源的肝脏可溶性复合物体外处理肿瘤细胞,四甲基偶氮唑盐比色法测定其对乳腺癌细胞EMT6增殖的影响.③体内实验:观察成年鼠肝脏可溶物质对乳腺癌细胞EMT6体内生长的抑制作用及其对荷瘤鼠生存状况的影响,包括不同给药剂量及不同给药途径两个实验,给药途径包括在接种肿瘤细胞部位的对侧腋下、同侧腋下、腹腔注射及灌胃等.结果:①体外实验显示不同来源的肝脏可溶性复合物能明显抑制肿瘤细胞EMT6增殖率,肿瘤增殖抑制率均显著高于血清白蛋白处理组(P<0.05),并呈剂量依赖性.②成年鼠肝脏可溶物质8mg/L组抑瘤率高于2,4 mg/L组(P<0.05),未观察到明显毒副效应.③比较不同给药途径,成年鼠肝脏可溶物质同侧注射组的抑瘤率较其他3组的抑瘤率高(P<0.05),各成年鼠肝脏可溶物质给予组的体质量增长率比相应生理盐水对照组高(P<0.05).④与相应生理盐水对照组比较,在同侧腋下注射成年鼠肝脏可溶物质的小鼠生存期明显延长(P<0.05).结论:肝脏可溶性复合物具有抑制肿瘤细胞生长的作用,并且呈一定的剂量依赖性.不同的给药途径中,在接种肿瘤细胞部位的同侧腋下给药抑瘤效果最好. 相似文献
982.
目的:调查了解山东泰安地区农村人群的血脂水平,为该地区农民心脑血管疾病的预防提供基础数据。方法:实验于2006-06随机选取泰安市两个自然村650人进行健康检查,男270人,女380人,年龄2~88岁。①650人均于早晨空腹采集静脉血3mL,静置凝固后,2h内分离血清,采用全自动生化分析仪常规测定患者血脂指标总胆固醇、三酰甘油水平。②总胆固醇>5.2mmol/L判定为高胆固醇血症,三酰甘油>1.7mmol/L判定为高三酰甘油血症。结果:650人全部完成血样采集与血脂指标检测。①不同性别血脂水平比较:被检人群男性三酰甘油水平显著高于女性[(1.16±1.47),(0.95±0.84)mmol/L,P<0.05];男女总胆固醇水平基本相似(P>0.05)。②不同年龄段血脂水平比较:8人因具体年龄段不祥被排除,剩余642人分为3个年龄段:2~30岁、31~50岁、51~88岁。结果31~50岁人群三酰甘油水平显著高于2~30岁人群[(1.14±1.47),(0.88±0.70)mmol/L,P<0.05],略高于51~88岁人群(P>0.05);51~88岁人群总胆固醇水平>31~50岁人群>2~30岁人群,相邻年龄段间比较差异均有显著性意义(P<0.001)。③各年龄段男女间血脂水平比较:2~30岁人群和51~88岁人群三酰甘油水平性别间差异均无显著性意义(P>0.05),但总胆固醇水平女性均显著高于男性[(2.38±1.47),(1.85±1.26)mmol/L,P<0.05;(4.48±0.92),(4.18±0.76)mmol/L,P0.01]。31~50岁人群男性三酰甘油水平显著高于女性[(1.51±2.06),(0.90±0.80)mmol/L,P<0.01],总胆固醇水平基本相似(P>0.05)。④各年龄段男女高血脂症构成比:31~50岁人群高三酰甘油血症构成比显著高于2~30岁、51~88岁人群(23.1%,5.5%,9.3%,P<0.01);随着年龄增高,各年龄段高胆固醇血症构成比逐渐升高,相邻年龄段间差异均有显著性意义(2.7%,8.6%,15.6%,P<0.01)。31~50岁人群男性高三酰甘油血症、高胆固醇血症的构成比显著高于女性(P<0.01);2~30岁、51~88岁人群男女间高血脂症的构成比基本相似(P>0.05)。结论:①山东泰安地区农村人群高三酰甘油血症,31~50岁年龄段患病率最高;高胆固醇血症患病率随年龄增长逐步上升,提示中年人健康体检尤为重要。②高脂血症应从青少年开始加大预防和保健力度,进行广泛和反复的健康教育,倡导健康的生活方式和生活行为。 相似文献
983.
984.
985.
986.
We have previously reported the activation of a triphasic current response by calcium injection in voltage-clamped, nonbursting neurons of Aplysia californica. Present evidence indicates that the second phase, a delayed inward current that peaks 10-20 seconds after the end of the injection, is a calcium-activated, nonselective cationic conductance. It can be carried by both sodium and calcium, is not sensitive to chloride concentration changes, but is voltage sensitive, decreasing in amplitude with hyperpolarization. 相似文献
987.
988.
Lack of long-term monoamine depletions following repeated or continuous exposure to cocaine 总被引:2,自引:0,他引:2
Cocaine was administered to rats for prolonged periods either by repeated injections (10 mg/kg twice daily for 10 days and 12.5 mg/kg 8 times daily for 10 days) or by continuous intravenous infusion (100 mg/kg/day for 21 days). None of the regimens produced long-lasting depletions of dopamine (DA), serotonin (5-HT), or major metabolites in striatum, hippocampus, hypothalamus, or somatosensory cortex. These results suggest that prolonged exposure to cocaine does not produce neurotoxicity like that observed with d-amphetamine or d-methylamphetamine. 相似文献
989.
A menopause-specific quality of life questionnaire: development and psychometric properties 总被引:7,自引:0,他引:7
John R. Hilditch Jacqueline Lewis Alice Peter Barbara van Maris Alan Ross Edmée Franssen Gordon H. Guyatt Peter G. Norton Earl Dunn 《Maturitas》1996,24(6):161-175
Objective:
to develop a condition-specific quality of life questionnaire for the menopause with documented psychometric properties, based on women's experience. Methods: Subjects: Women 2–7 years post-menopause with a uterus and not currently on hormone replacement therapy. Questionnaire development: A list of 106 menopause symptoms was reduced using the importance score method. Replies to the item-reduction questionnaire from 88 women resulted in a 30-item questionnaire with four domains, vasomotor, physical, psychosocial and sexual, and a global quality of life question. Psychometric properties: A separate sample of 20 women was used to determine face validity, and a panel of experts was used to confirm content validity. Reliability, responsiveness and construct validity were determined within the context of a randomized controlled trial.Construct validation involved comparison with the Neugarten and Kraines' Somatic, Psychosomatic and Psychologic subscales, the reported intensity of hot flushes, the General Well-Being Schedule, Channon and Ballinger's Vaginal Symptoms Score and Libido Index, and the Life Satisfaction Index.Results:
The face validity score was 4.7 out of a possible 5. Content validity was confirmed. Test-retest reliability measures, using intraclass correlation coefficients were 0.81, 0.79, 0.70 and 0.55 for the physical, psychosocial, sexual domains and the quality of life question. The intraclass correlation coefficient for the vasomotor domain was 0.37 but there is evidence of systematic change. Discriminative construct validity showed correlation coefficients of 0.69 for the physical domain, 0.66 and 0.40 for the vasomotor domain, 0.65 and −0.71 for the psychosocial domain, 0.48 and 0.38 for the sexual domain, and 0.57 for the quality of life question. Evaluative construct validity showed correlation coefficients of 0.60 for the physical domain, 0.28 for the vasomotor domain, 0.55 and −0.54 for the psychosocial domain, 0.54 and 0.32 for the sexual domain, and 0.12 for the quality of life question. Responsiveness scores ranged from 0.78 to 1.34.Conclusions:
The MENQOL (Menopause-Specific Quality of Life) questionnaire is a self-administered instrument which functions well in differentiating between women according to their quality of life and in measuring changes in their quality of life. 相似文献990.
Steven B. Karch MD Terry Lewis MD Sandra Young RN Don Hales NREMT-P Chih-Hsiang Ho PhD 《The American journal of emergency medicine》1996,14(7):617-619
Neither the success nor the complication rate for field intubation of trauma patients is known with any certainty. A retrospective audit of 94 severely injured patients who required field intubation was undertaken. Fifty percent (13 of 26) of survivors and 67% (37 of 71) of nonsurvivors were successfully intubated in the field (not significant). Mechanism of injury was similar in both groups, but survivors were younger (27 v 60 years, P = .049) and less critically injured, as reflected by their Injury Severity Scale scores, their Trauma Scores, and their field Glasgow Coma Scale scores (22.1 v 30.8, P = .0035; 7.7 v 4.2, P < .0002; and 6.3 v 3.3, P < .0001). When compared with previously published studies of medical patients with cardiac arrest, the success rate was lower in our trauma patients. When compared with patients having similar injuries intubated at the trauma center, field intubation was three times more likely to be associated with the development of nosocomial pneumonia than was hospital intubation. 相似文献