全文获取类型
收费全文 | 1985951篇 |
免费 | 143193篇 |
国内免费 | 3673篇 |
专业分类
耳鼻咽喉 | 26900篇 |
儿科学 | 64106篇 |
妇产科学 | 56126篇 |
基础医学 | 289866篇 |
口腔科学 | 55471篇 |
临床医学 | 178283篇 |
内科学 | 390590篇 |
皮肤病学 | 42605篇 |
神经病学 | 158809篇 |
特种医学 | 76359篇 |
外国民族医学 | 584篇 |
外科学 | 293708篇 |
综合类 | 41890篇 |
现状与发展 | 3篇 |
一般理论 | 788篇 |
预防医学 | 156994篇 |
眼科学 | 45209篇 |
药学 | 144047篇 |
7篇 | |
中国医学 | 3568篇 |
肿瘤学 | 106904篇 |
出版年
2018年 | 20567篇 |
2016年 | 17344篇 |
2015年 | 19922篇 |
2014年 | 27869篇 |
2013年 | 42872篇 |
2012年 | 57950篇 |
2011年 | 61761篇 |
2010年 | 36502篇 |
2009年 | 34820篇 |
2008年 | 58562篇 |
2007年 | 62393篇 |
2006年 | 62172篇 |
2005年 | 61059篇 |
2004年 | 58648篇 |
2003年 | 56388篇 |
2002年 | 54944篇 |
2001年 | 87561篇 |
2000年 | 89570篇 |
1999年 | 76010篇 |
1998年 | 21387篇 |
1997年 | 19478篇 |
1996年 | 19856篇 |
1995年 | 18574篇 |
1994年 | 17515篇 |
1993年 | 16448篇 |
1992年 | 60316篇 |
1991年 | 58814篇 |
1990年 | 57412篇 |
1989年 | 55360篇 |
1988年 | 51448篇 |
1987年 | 50396篇 |
1986年 | 48253篇 |
1985年 | 45760篇 |
1984年 | 34630篇 |
1983年 | 29897篇 |
1982年 | 17947篇 |
1981年 | 16089篇 |
1979年 | 32885篇 |
1978年 | 23705篇 |
1977年 | 19956篇 |
1976年 | 18585篇 |
1975年 | 20276篇 |
1974年 | 24465篇 |
1973年 | 23837篇 |
1972年 | 22538篇 |
1971年 | 20926篇 |
1970年 | 19918篇 |
1969年 | 18800篇 |
1968年 | 17677篇 |
1967年 | 16010篇 |
排序方式: 共有10000条查询结果,搜索用时 24 毫秒
61.
Contour defects resulting in deformity caused by lack of tissue can be improved by conventional surgery using autologous tissue, but there is always a donor site morbidity. Integra has been available since the early 1980's for use in acute burns and more recently in reconstruction. It has been shown histologically to act as a tissue regeneration template. The regenerated dermis is buried under an autologous thin split-skin graft. In this study, the principle of burying Integra (without the silicone layer) has been applied to deep tissue defects in 12 reconstructive cases. Such regenerated tissues survive at least 3 years after burying. Modification to the technique to avoid visible edges are being developed. 相似文献
62.
63.
64.
F Pitta T Troosters V S Probst M A Spruit M Decramer R Gosselink 《The European respiratory journal》2006,27(5):1040-1055
Accurate assessment of the amount and intensity of physical activity in daily life is considered very important due to the close relationship between physical activity level, health, disability and mortality. For this reason, assessment of physical activity in daily life has gained interest in recent years, especially in sedentary populations, such as patients with chronic obstructive pulmonary disease (COPD). The present article aims to compare and discuss the two kinds of instruments more commonly used to quantify the amount of physical activity performed by COPD patients in daily life: subjective methods (questionnaires, diaries) and motion sensors (electronic or mechanical methods). Their characteristics are summarised and evidence of their validity, reliability and sensitivity is discussed, when available. Subjective methods have practical value mainly in providing the patients' view on their performance in activities of daily living and functional status. However, care must be taken when using subjective methods to accurately quantify the amount of daily physical activity performed. More accurate information is likely to be available with motion sensors rather than questionnaires. The selection of which motion sensor to use for quantification of physical activity in daily life should depend mainly on the purpose of its use. 相似文献
65.
R H Green C E Brightling S McKenna B Hargadon N Neale D Parker C Ruse I P Hall I D Pavord 《The European respiratory journal》2006,27(6):1144-1151
There is increasing evidence that the assessment of eosinophilic airway inflammation using induced sputum and measurement of airway hyperresponsiveness provides additional, clinically important information concerning asthma control. The aim of this study was to directly compare the effects of different treatments on these markers in patients with asthma and persistent symptoms, despite the use of low-dose inhaled corticosteroids. A double-blind four-way crossover study was performed, which compared a 1-month treatment with budesonide 400 mug b.i.d., additional formoterol, additional montelukast and placebo in 49 patients with uncontrolled asthma despite budesonide 100 mug b.i.d., with each treatment separated by a 4-week washout period. The change in sputum eosinophil count with formoterol (2.4 to 3.8% change, 0.6-fold reduction, 95% confidence interval (CI) 0.5-0.9) differed significantly from placebo (2.8 to 2.5% change, 1.1-fold reduction, 95% CI 0.7-1.6) and high-dose budesonide (2.7 to 1.6% change, 1.6-fold reduction, 95% CI 1.2-2.2). The effects of montelukast did not differ from placebo. The changes in methacholine airway responsiveness were small and did not differ between treatments. High-dose budesonide had the broadest range of beneficial effects on other outcomes, including symptom scores, morning peak expiratory flow and forced expiratory volume in one second. In conclusion, treatment given in addition to low-dose inhaled corticosteroids results in modest benefits. Formoterol and high-dose budesonide have contrasting effects on eosinophilic airway inflammation. 相似文献
66.
J Müller-Quernheim K I Gaede E Fireman G Zissel 《The European respiratory journal》2006,27(6):1190-1195
An increase in chronic beryllium disease (CBD) has been suggested due to higher industrial use of beryllium alloys. Since occupational CBD is a perfect phenocopy of sarcoidosis, it might be misdiagnosed as sarcoidosis. In the current it was hypothesised that CBD exists in cohorts of sarcoidosis patients. In a prospective case study, sarcoidosis patients were evaluated for potential beryllium exposure. In those patients in whom beryllium exposure was confirmed and beryllium hypersensitivity demonstrated, the diagnosis of sarcoidosis was rejected and corrected to CBD. In 84 patients seen for re-evaluation or making a diagnosis of sarcoidosis, beryllium exposure was recognised and a diagnosis of CBD was made in 34 out of 84 patients. The time lag between clinical diagnosis of sarcoidosis and the final diagnosis of CBD ranged 0-18 yrs (median 3 yrs) and the mean (range) age at time of diagnosis of CBD was 43.9(25-80) yrs. Beryllium-contaminated workplaces causing disease encompassed a wide spectrum of industries and technical trades in which beryllium-exposure is generally not perceived as a health hazard. In conclusion, chronic beryllium disease still belongs to the spectrum of differential diagnoses of granulomatous disorders. 相似文献
67.
C T Gan G P McCann J T Marcus S A van Wolferen J W Twisk A Boonstra P E Postmus A Vonk-Noordegraaf 《The European respiratory journal》2006,28(6):1190-1194
The aim of the current study was to investigate whether alterations in N-terminal pro brain natriuretic peptide (NT-proBNP) reflect changes in right ventricular structure and function in pulmonary hypertension patients during treatment. The study consisted of 30 pulmonary hypertension patients; 15 newly diagnosed and 15 on long-term treatment. NT-proBNP, right heart catheterisation and cardiac magnetic resonance imaging measurements were performed, at baseline and follow-up. There were no significant differences between newly diagnosed patients and those on treatment at baseline or follow-up with respect to NT-proBNP, haemodynamics and right ventricular parameters. Relative changes in NT-proBNP during treatment were correlated to the relative changes in right ventricular end-diastolic volume index (r = 0.59), right ventricular mass index (r = 0.62) and right ventricular ejection fraction (r = -0.81). N-terminal pro brain natriuretic peptide measurements reflect changes in magnetic resonance imaging-measured right ventricular structure and function in pulmonary hypertension patients. An increase in N-terminal pro brain natriuretic peptide over time reflects right ventricular dilatation concomitant to hypertrophy and deterioration of systolic function. 相似文献
68.
69.
C. M. Crceles J. M. Serrano P. Marín E. Escudero E. Fernndez‐Varn 《Transboundary and Emerging Diseases》2006,53(6):300-304
The pharmacokinetics (PK) of moxifloxacin in healthy white New Zealand rabbits was studied following intravenous (IV) and subcutaneous (SC) administration routes as well as a SC long‐acting poloxamer 407 gel formulation (SC‐P407). Moxifloxacin concentrations were determined by high‐performance liquid chromatography assay with fluorescence detection. Mean half‐life for IV, SC and SC‐P407 routes was 2.15, 5.41 and 11.09 h. Clearance value after IV dosing was 0.78 l/kg/h. After SC administration, the mean absolute bioavailability was 117% and the Cmax was 1.61 ± 0.49 mg/l. After SC‐P407 administration, the bioavailability was 44% and the Cmax 1.83 was ±0.62 mg/l. No adverse effects were observed in any of the rabbits following IV, SC and SC‐P407 administration of moxifloxacin. Minimal inhibitory concentrations of moxifloxacin against different strains of Staphylococcus aureus from different european countries were used to compute the main pharmacodynamic (PD) surrogate markers of efficacy. The high tolerability of this SC‐P407 formulation and the favourable PK behaviour such as the long half‐life, acceptable bioavailability and excellent PK–PD ratios achieved indicate that it is likely to be effective in rabbits. 相似文献
70.