全文获取类型
收费全文 | 18807篇 |
免费 | 1781篇 |
国内免费 | 248篇 |
专业分类
耳鼻咽喉 | 50篇 |
儿科学 | 566篇 |
妇产科学 | 438篇 |
基础医学 | 1755篇 |
口腔科学 | 165篇 |
临床医学 | 4289篇 |
内科学 | 1922篇 |
皮肤病学 | 60篇 |
神经病学 | 1202篇 |
特种医学 | 291篇 |
外科学 | 1849篇 |
综合类 | 1945篇 |
一般理论 | 2篇 |
预防医学 | 4333篇 |
眼科学 | 29篇 |
药学 | 876篇 |
12篇 | |
中国医学 | 225篇 |
肿瘤学 | 827篇 |
出版年
2024年 | 57篇 |
2023年 | 447篇 |
2022年 | 681篇 |
2021年 | 1031篇 |
2020年 | 1026篇 |
2019年 | 993篇 |
2018年 | 929篇 |
2017年 | 946篇 |
2016年 | 890篇 |
2015年 | 835篇 |
2014年 | 1399篇 |
2013年 | 1686篇 |
2012年 | 1185篇 |
2011年 | 1179篇 |
2010年 | 961篇 |
2009年 | 866篇 |
2008年 | 916篇 |
2007年 | 856篇 |
2006年 | 678篇 |
2005年 | 536篇 |
2004年 | 438篇 |
2003年 | 357篇 |
2002年 | 299篇 |
2001年 | 230篇 |
2000年 | 216篇 |
1999年 | 186篇 |
1998年 | 137篇 |
1997年 | 148篇 |
1996年 | 89篇 |
1995年 | 99篇 |
1994年 | 95篇 |
1993年 | 74篇 |
1992年 | 59篇 |
1991年 | 43篇 |
1990年 | 35篇 |
1989年 | 35篇 |
1988年 | 30篇 |
1987年 | 32篇 |
1986年 | 19篇 |
1985年 | 23篇 |
1984年 | 24篇 |
1983年 | 19篇 |
1982年 | 13篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 8篇 |
1978年 | 6篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1973年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
消化道恶性肿瘤确诊初期患者社会支持与生命质量的调查 总被引:6,自引:1,他引:5
目的 调查消化道恶性肿瘤确诊初期的患者半年中的社会支持和生命质量变化。方法 采用社会支持评定量表和CARES-SF对146名患者的社会支持和生命质量进行为期半年的追踪调查。结果 消化道恶性肿瘤确诊初期患者的生命质量为中等,其中婚姻关系维度、性关系维度得分半年后下降。患者所获得的社会支持最多的是情感支持,其次是实际支持,信息支持为第三位。情感支持大多来源于家庭成员,信息支持大多来源于医务人员。患者大多很少参与社交活动。在半年中情感支持、实际支持、信息支持的变化模式不一。诊断初期的患者不能有效地利用社会支持。结论 应对确诊初期患者加强咨询,以充分识别和利用社会资源。应持续评估患者的生命质量和社会支持,并制订干预方案,提高消化道恶性肿瘤确诊初期患者的社会支持程度,最终提高其生命质量。 相似文献
72.
深圳南山0~2岁儿童营养状况及其影响因素的调查研究 总被引:1,自引:1,他引:0
目的 了解深圳南山0~2岁儿童营养状况及影响因素。方法 Z评分法、NCHS标准评价儿童营养,检测血红蛋白和血Cu、Fe、Zn、Ca、Mg、P,问卷调查有关社会环境因素。结果 深圳南山0~2岁儿童营养不良率为8.08%。常住儿童与暂住儿童营养不良率间差别有显著性意义(P<0.01)。营养不良的影响因素:儿童户籍是否常、暂住,膳食结构中谷类食物量,婴儿期是否母乳喂养。儿童年龄与贫血患病率间存在一定线性依从关系(P<0.01),暂住与常住儿童贫血患病率间差别有显著性意义(尸<0.05)。235名儿童的血Cu、Mg值均正常,而儿童缺Ca、Zn、P、Fe的发生率分别为71.06%、54.89%、22.12%和6.8%。结论 我区0~2岁儿童营养状况不容乐观,尤其暂住儿童更是高危人群。我们在重点营养干预同时,要注意改善整体儿童营养状况。 相似文献
73.
Michael S. Runyon MD Peter B. Richman MD Jeffrey A. Kline MD 《Academic emergency medicine》2007,14(1):53-57
Background Several clinical decision rules (CDRs) have been validated for pretest probability assessment of pulmonary embolism (PE), but the authors are unaware of any data quantifying and characterizing their use in emergency departments. Objectives To characterize clinicians' knowledge of and attitudes toward two commonly used CDRs for PE. Methods By using a modified Delphi approach, the authors developed a two‐page paper survey including 15 multiple‐choice questions. The questions were designed to determine the respondents' familiarity, frequency of use, and comprehension of the Canadian and Charlotte rules. The survey also queried the frequency of use of unstructured (gestalt) pretest probability assessment and reasons why physicians choose not to use decision rules. The surveys were sent to physicians, physician assistants, and medical students at 32 academic and community hospitals in the United States and the United Kingdom. Results Respondents included 555 clinicians; 443 (80%) work in academic practice, and 112 (20%) are community based. Significantly more academic practitioners (73%) than community practitioners (49%) indicated familiarity with at least one of the two decision rules. Among all respondents familiar with a rule, 50% reported using it in more than half of applicable cases. A significant number of these respondents could not correctly identify a key component of the rule (23% for the Charlotte rule and 43% for the Canadian rule). Fifty‐seven percent of all respondents indicated use of gestalt rather than a decision rule in more than half of cases. Conclusions Academic clinicians were more likely to report familiarity with either of these two specific decision rules. Only one half of all clinicians reporting familiarity with the rules use them in more than 50% of applicable cases. Spontaneous recall of the specific elements of the rules was low to moderate. Future work should consider clinical gestalt in the evaluation of patients with possible PE. 相似文献
74.
Edward C. Kohaut John Whelchel F. Bryson Waldo Arnold G. Diethelm 《Pediatric nephrology (Berlin, Germany)》1987,1(2):150-153
Nine infants, who presented with renal failure within the first 3 months of life, were treated with continuous ambulatory peritoneal dialysis (CAPD). Seven infants survived to an age of 12–15 months, when they received transplants. Two patients died while on CAPD. Six infants are alive with a functioning renal allograft, at an average age of 35.5 months and an average of 22 months post-transplant. Neurological development is normal in four of the six infants tested. The mean current height of the six transplant recipients is just below 2 SD from the mean. 相似文献
75.
无创正压通气不同压力支持水平对正常人呼吸做功的影响 总被引:2,自引:0,他引:2
目的 :观察无创正压通气 (NIPPV)不同压力水平对正常人呼吸做功的影响 ,为临床合理地应用NIPPV提供理论依据。方法 :选择 9例正常人行NIPPV并寻找出“最舒适”的吸气压力水平 (IPAP) ,在此压力基础上增加或减少 2 5 %的压力 ,构成低IPAP、最舒适IPAP和高IPAP三个压力水平 ,每一IPAP水平通气 15min以上 ,比较不同压力水平呼吸做功改变。结果 :受试者认为“最舒适”的IPAP为 (11.33± 3.2 0 )cmH2 O ,EPAP为 (4 .5 6± 0 .88)cmH2 O[相当于PSV水平为 (6 .77± 3.2 0 )cmH2 O]。与自主呼吸相比 ,NIPPV增加VE的同时 ,总的呼吸做功(Wtot)明显增加 (P <0 .0 5 ) ,而受试者吸气肌做功占总的吸气做功的百分比 (Wi,p/Wi)明显减少 (P <0 .0 5 )。在最舒适IPAP时 ,Wi,p/Wi降低到基础值的 14 %± 9%。这种变化趋势与IPAP的水平相关。结论 :NIPPV可以显著降低吸气肌肉做功。吸气肌做功减少的比例与IPAP的水平相关。研究的结果为NIPPV时PSV的参数设定提供了生理学的依据。 相似文献
76.
Dawn Stacey RN MScN CON Annette M. O'Connor RN PhD † Cathy DeGrasse RN MScN ‡ Shailendra Verma MD FRCP § 《Health expectations》2003,6(1):3-18
Objective To develop and evaluate the effectiveness of a breast cancer prevention decision aid for women aged 50 and older at higher risk of breast cancer. Design Pre‐test–post‐test study using decision aid alone and in combination with counselling. Setting Breast Cancer Risk Assessment Clinic. Participants Twenty‐seven women aged 50–69 with 1.66% or higher 5‐year risk of breast cancer. Intervention Self‐administered breast cancer prevention decision aid. Main outcome measures Acceptability; decisional conflict; knowledge; realistic expectations; choice predisposition; intention to improve life‐style practices; psychological distress; and satisfaction with preparation for consultation. Results The decision aid alone, or in combination with counselling, decreased some dimensions of decisional conflict, increased knowledge (P < 0.01), and created more realistic expectations (P < 0.01). The aid in combination with counselling, significantly reduced decisional conflict (P < 0.01) and psychological distress (P < 0.02), helped the uncertain become certain (P < 0.02), and increased intentions to adopt healthier life‐style practices (P < 0.03). Women rated the aid as acceptable, and both women and practitioners were satisfied with the effect it had on the counselling session. Conclusion The decision aid shows promise as a useful decision support tool. Further research should compare the effect of the decision aid in combination with counselling to counselling alone. 相似文献
77.
F. BRUNET J. P. MIRA C. CERF M. BELGHITH O. SOUBRANE J. L. TERMIGNON† B. RENAUD L. FIEROBE I. HAMY M. MONCHI E. DESLANDE A. BRUSSET† J. F. DHAINAUT 《Artificial organs》1994,18(11):826-832
Abstract: This open clinical study was aimed at testing the hypothesis that an intravascular oxygenator (IVOX) may help to perform permissive hypoventilation in 10 patients with severe ARDS. After initial evaluation, we tried to reduce ventilator settings before and after IVOX implantation. Before IVOX, poor clinical tolerance and worsening oxygenation did not allow for a significant decrease in ventilator settings. With IVOX, peak inspiratory pressure (PIP) was reduced from 47 to 39 cm H2 O (p = 0. 005) and minute ventilation from 13 ± 3. 5 to 11 ± 3 L/min. CO2 removal by IVOX allowed a significant decrease in Paco2 from 66 ± 15 to 59 ± 13 mm Hg. Improvement of oxygenation with IVOX was not signify cant. Furthermore, interruption of oxygen flow through IVOX did not change oxygenation variables. Tolerance of the IVOX device was good, but insertion of the device was followed by a significant decrease in both cardiac index and pulmonary wedge pressure. In conclusion, IVOX improves tolerance of hypoventilation by limiting hypercapnia in ARDS patients. These preliminary results must be confirmed by a randomized controlled study 相似文献
78.
目的 介绍应用经皮内镜下胃造口术(PEG)实施肠内营养支持。方法 在内镜引导下行胃造口术.7例病人均予以肠内营养。结果 7例病人置管8次,成功率100%,6例经治疗后恢复情况好,无严重并发症。结论在肠内营养输注途径中PEG具有创伤小、时间短、经济,安全等特点。易于护理和长期使用。 相似文献
79.
基于混合遗传算法的心脏病决策支持系统研究 总被引:1,自引:0,他引:1
将遗传算法和 BP算法相结合 ,建立了一个基于混合遗传算法的心脏病决策支持系统来鉴别诊断五种常见心脏病 (冠心病 ,高血压性心脏病 ,风湿性心脏病 ,慢性肺原性心脏病和先天性心脏病 )。一个含有 35 2份心脏病的数据库用来构建和测试了该系统。实验结果表明 ,构建的系统对这五种心脏病均有较好的诊断识别率 ,系统的平均识别准确性达 90 .6 % ,各疾病的用户准确性和程序准确性均大于 85 .0 % ,表现出良好的心脏病的临床诊断决策支持能力 相似文献
80.
Hepatocyte isolation from pig livers after warm ischaemic injury 总被引:9,自引:0,他引:9
Michael R. Schön Gero Puhl Jörg Gerlach Jorn Frank Peter Neuhaus 《Transplant international》1994,7(S1):159-162
Abstract Hepatocyte cultures have been used extensively for a wide variety of physiological, pharmacological and experimental studies. The warm ischaemic period before isolation is kept to a minimum to achieve a high yield of cells isolated and a good viability for culture. We have recently introduced a new concept of liver resuscitation after warm ischaemia that is based on a 3-h reperfusion period with an improved perfusate and simultaneous dialysis. In this study, we applied the new technique for hepatocyte isolation from livers subjected to 80 min of complete ischaemia at 37 °C. Cell yield was improved by a resuscitating perfusion from 58% to 73% and viability from 39% to 76%. 相似文献