全文获取类型
收费全文 | 281943篇 |
免费 | 23462篇 |
国内免费 | 6670篇 |
专业分类
耳鼻咽喉 | 3577篇 |
儿科学 | 6012篇 |
妇产科学 | 4276篇 |
基础医学 | 22777篇 |
口腔科学 | 8135篇 |
临床医学 | 26336篇 |
内科学 | 28854篇 |
皮肤病学 | 2940篇 |
神经病学 | 13151篇 |
特种医学 | 7542篇 |
外国民族医学 | 16篇 |
外科学 | 35828篇 |
综合类 | 45699篇 |
现状与发展 | 12篇 |
一般理论 | 29篇 |
预防医学 | 33506篇 |
眼科学 | 2828篇 |
药学 | 26302篇 |
442篇 | |
中国医学 | 32746篇 |
肿瘤学 | 11067篇 |
出版年
2024年 | 1198篇 |
2023年 | 5649篇 |
2022年 | 10270篇 |
2021年 | 13930篇 |
2020年 | 13030篇 |
2019年 | 14418篇 |
2018年 | 12864篇 |
2017年 | 11231篇 |
2016年 | 10243篇 |
2015年 | 9594篇 |
2014年 | 18884篇 |
2013年 | 19048篇 |
2012年 | 16414篇 |
2011年 | 18182篇 |
2010年 | 15140篇 |
2009年 | 12747篇 |
2008年 | 11877篇 |
2007年 | 12030篇 |
2006年 | 10551篇 |
2005年 | 8944篇 |
2004年 | 7384篇 |
2003年 | 6472篇 |
2002年 | 5037篇 |
2001年 | 4295篇 |
2000年 | 3651篇 |
1999年 | 3048篇 |
1998年 | 2486篇 |
1997年 | 2253篇 |
1996年 | 1870篇 |
1995年 | 1852篇 |
1994年 | 1678篇 |
1993年 | 1426篇 |
1992年 | 1329篇 |
1991年 | 1220篇 |
1990年 | 1049篇 |
1989年 | 1030篇 |
1988年 | 953篇 |
1987年 | 859篇 |
1986年 | 783篇 |
1985年 | 2210篇 |
1984年 | 2501篇 |
1983年 | 1600篇 |
1982年 | 2086篇 |
1981年 | 1536篇 |
1980年 | 1349篇 |
1979年 | 1223篇 |
1978年 | 1009篇 |
1977年 | 790篇 |
1976年 | 875篇 |
1975年 | 586篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
本文提出了我国医疗器械产业中数字化技术发展中存在的主要问题,并分析了问题产生的原因。 相似文献
62.
Therapeutic Consequences of Variation in Intraarterial Pressure Measurements After Iliac Angioplasty
Eric Tetteroo Cees Haaring Andries D. van Engelen Yolanda van der Graaf Willem P.T.M. Mali 《Cardiovascular and interventional radiology》1997,20(6):426-430
Purpose: To assess the accuracy of intraarterial measurement of transstenotic pressure gradients for the detection of hemodynamically
suboptimal iliac angioplasty.
Methods: In 14 patients, referred for diagnostic angiography, mean pressure gradients in the aorta and iliac artery were obtained
twice, using a double-sensor pressure catheter. Additional iliac measurements were performed during pharmacologically induced
flow augmentation. Repeatability was assessed by calculation of the mean difference plus standard deviation (MD ± SD) and
repeatability coefficient (2 × SD). These results were extrapolated to 137 iliac angioplasty procedures with secondary stenting
where there was a residual pressure gradient > 10 mmHg.
Results: MD ± SD for repeated measurements at rest and during flow augmentation were 0 ± 2 mmHg and 1 ± 3 mmHg, respectively. Repeatability
coefficients were 3 and 6 mmHg. Mean pressure gradients after hemodynamically insufficient angioplasty were 8 ± 7 mmHg at
rest and 17 ± 5 mmHg following vasodilatation. Inaccurate pressure recordings may have led to inappropriate stent placement
in less than 2.5%, and inappropriate denial of stent placement in less than 5% of the lesions.
Conclusion: Variability of intraarterial pressure measurements has little consequence in the detection of hemodynamically significant
stenosis after angioplasty.
Received: 0/00/00/Accepted: 0/00/00 相似文献
63.
Spleen sizing by ultrasound in polycythaemia and thrombocythaemia: comparison with SPECT 总被引:3,自引:1,他引:2
M. Messinezy L. M. MacDonald T. O. Nunan N. B. Westwood S. Chinn & T. C. Pearson 《British journal of haematology》1997,98(1):103-107
Detection of non-palpable early splenic enlargement may aid diagnosis of primary polycythaemia (PP) and primary thrombocythaemia (PT). In this study linear spleen sizing by ultrasound has been compared with spleen volume estimation by single photon emission computerized tomography (SPECT) in 26 patients. Spleen length by ultrasound correlated well with SPECT volume estimation.
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
64.
A. Trovato S. Kirjavainen E. M. Galati A. M. Forestieri L. Iauk 《Phytotherapy research : PTR》1995,9(8):591-593
The decoction of Sclerocarya birroea Hochst. shows hypoglycaemic effects, an increase in plasma IRI in normal rats and an incremented oral-glucose tolerance. The decoction is also active against diet-induced hypercholesterolaemia. 相似文献
65.
66.
R. Jayasuriya V. Westley-Wise T. Dunn K. Nydam D. Jeffs 《Internal medicine journal》1993,23(6):672-677
Background: The management and follow-up of asthma patients presenting at Accident and Emergency (A&E) departments have mostly been studied in children's hospitals or specialised teaching hospitals. Aims: To study the adequacy of assessment, treatment and follow-up of patients presenting at A&E departments in non-teaching hospitals. Methods: A twenty-five per cent sample of presentations to A&E departments in all public hospitals in the Illawarra for one year was selected for a case note audit. Information on demographics, assessment, management and referral was extracted from the A&E case notes and medical records of cases with documentation of a final diagnosis of asthma. Chi square and Fischer's Exact tests were used for comparisons among hospitals. Results: Of 359 presentations with a final diagnosis of asthma, 88% were self referred and only 5% were first presentations. Objective measures of airways obstruction was not documented in 34% of admissions and 48% of nonadmissions. There was no documented follow-up in 28% of cases. The assessment and management of asthma in A&E was significantly poorer in smaller hospitals. Conclusion: Evidence of high use of A&E as a primary care facility by asthma patients was found in the study. There is a need to implement protocols to optimise assessment and treatment of asthma in smaller hospitals. (Aust NZ J Med 1993; 23: 672–677.). 相似文献
67.
Ihsan A. Badr 《International ophthalmology》1993,17(3):155-160
The region is characterized by diversity in cultural, political, economic and health conditions. Blindness in the region varies from 6.4% to 0.2% with cataract ranking highly as an underlying cause. There is a need to develop national policies to deliver affordable, technically suitable, and cost effective management plans to reduce cataract. Economic, demographic, health, and manpower statistics are essential information to be considered in formulating such policies. 相似文献
68.
鼻部源性突眼的CT分析 总被引:1,自引:0,他引:1
目的:为了提高对鼻部源性突眼的认识。材料和方法:本文19例鼻部源性突眼,其中鼻咽癌7例,鼻咽纤维血管瘤2例,鼻腔纤维血管瘤、恶性肉芽肿和嗅神经母细胞瘤各1例,上颌窦癌和软骨肉瘤各2例,上颌窦恶性肉芽肿、纤维肉瘤和恶性纤维组织细胞瘤各1例,全部病例均作轴位CT扫描,12例加作增强扫描,详细分析了它们CT表现。结果:源于鼻咽的放疗前鼻咽癌和纤维血管瘤,其病变主要位于鼻咽腔和咽旁,后者显著增强并有钙斑,与前者不同;源于上颌窦的肿瘤,病变占据上颌窦的全部或大部分,软骨肉瘤有钙斑且无强化,易与其它肿瘤区别,它们破坏上颌窦顶部进入眼眶;鼻腔嗅神经母细胞瘤在鼻腔和筛窦形成肿块,破坏筛骨眶板侵入眼眶。结论:根据CT所见,可判断突眼原因。 相似文献
69.
Sarah A. Taylor Jacqueline Benedetti David Schuller Stephen P. Richman Goronwy O. Broun Alexander Hantel 《Investigational new drugs》1993,11(2-3):227-229
Summary Twenty-two patients with recurrent or metastatic squamous cell carcinoma of the head and neck were treated with piroxantrone 150 mg/m2 intravenously every 21 days. There were no objective responses. The 95% upper confidence bound for response is 15%. Primary toxicity was hematologic. 相似文献
70.
Rosemary Cant 《Australian Occupational Therapy Journal》1993,40(3):113-121
Newer policies of community care for those with disabilities have resulted in the home becoming the usual site of care. Policy makers must now give attention to the needs of those at home giving this care. This article explores the constraints on sociability opportunities of 73 mothers who were caring for children with disabilities. These opportunities are often built into leisure pursuits for women without caring responsibilities. However, choice of out-of-house leisure activity was circumscribed for the mothers in this study and their reported leisure activities revolved around home and neighbourhood. Even these sites offered limited scope for sociability because of the way in which caring affected domestic space and because of the characteristics of the modern Australian suburb. It is argued in this paper that personal time and personal domestic space are needed by care-givers so their sociability needs can be fulfilled. An understanding of the constraints imposed by use of the home as a place of care may make possible the planning of a rearrangement of domestic space to increase sociability opportunities for carers. 相似文献