全文获取类型
收费全文 | 26930篇 |
免费 | 1369篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 361篇 |
儿科学 | 1485篇 |
妇产科学 | 609篇 |
基础医学 | 2903篇 |
口腔科学 | 581篇 |
临床医学 | 1613篇 |
内科学 | 5778篇 |
皮肤病学 | 779篇 |
神经病学 | 1692篇 |
特种医学 | 844篇 |
外科学 | 3529篇 |
综合类 | 795篇 |
一般理论 | 15篇 |
预防医学 | 1282篇 |
眼科学 | 1724篇 |
药学 | 2360篇 |
中国医学 | 181篇 |
肿瘤学 | 1851篇 |
出版年
2023年 | 193篇 |
2022年 | 505篇 |
2021年 | 988篇 |
2020年 | 509篇 |
2019年 | 650篇 |
2018年 | 820篇 |
2017年 | 557篇 |
2016年 | 679篇 |
2015年 | 672篇 |
2014年 | 1055篇 |
2013年 | 1264篇 |
2012年 | 1785篇 |
2011年 | 1905篇 |
2010年 | 1011篇 |
2009年 | 846篇 |
2008年 | 1328篇 |
2007年 | 1371篇 |
2006年 | 1325篇 |
2005年 | 1158篇 |
2004年 | 1039篇 |
2003年 | 881篇 |
2002年 | 798篇 |
2001年 | 706篇 |
2000年 | 702篇 |
1999年 | 564篇 |
1998年 | 234篇 |
1997年 | 174篇 |
1996年 | 144篇 |
1995年 | 150篇 |
1994年 | 115篇 |
1993年 | 99篇 |
1992年 | 368篇 |
1991年 | 371篇 |
1990年 | 338篇 |
1989年 | 328篇 |
1988年 | 285篇 |
1987年 | 251篇 |
1986年 | 234篇 |
1985年 | 232篇 |
1984年 | 171篇 |
1983年 | 135篇 |
1981年 | 93篇 |
1979年 | 157篇 |
1978年 | 97篇 |
1977年 | 81篇 |
1975年 | 83篇 |
1974年 | 100篇 |
1973年 | 93篇 |
1972年 | 118篇 |
1970年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
31.
C S Pant D K Gupta R C Sharma A S Gautam R M Bhatt 《Indian journal of malariology》1992,29(4):235-239
Frequency of sickle cell in Scheduled Caste and Scheduled Tribe populations was found to be 1.5 and 14.9% respectively, whereas G-6-PD deficiency was 5.9 and 4.2% respectively. Blood group B was dominant in both the communities. A significantly lower frequency of P. falciparum malaria was observed among sicklers. 相似文献
32.
Madhuri Dadwal Chander Mohan D. R. Sharma 《Indian journal of otolaryngology and head and neck surgery》2007,59(3):261-263
Secondary tuberculosis of pharynx is a rare condition as pharynx is not a common site for clinically manifest tuberculosis.
A rare and unusual case of secondary oropharyngeal tuberculosis in a 40 years male patient, who presented with an ulceroproliferative
lesion of oropharynx extending to nasopharynx and laryngopharynx is being reported. 相似文献
33.
Reticulate acropigmentation of Kitamura in a mother and her daughter is reported. Both demonstrated peri-orbital involvement in addition to involvement of acral areas, face and eyelids which has not been recorded before. 相似文献
34.
Randomized, double-blind, controlled trial of long-term diuretic therapy for bronchopulmonary dysplasia 总被引:2,自引:0,他引:2
S G Albersheim A J Solimano A K Sharma J A Smyth A Rotschild B J Wood S B Sheps 《The Journal of pediatrics》1989,115(4):615-620
The effects of continuous therapy with hydrochlorothiazide and spironolactone on pulmonary function in 34 premature infants with severe bronchopulmonary dysplasia were assessed in a randomized double-blind controlled trial. Subjects were greater than or equal to 30 days old, were supported by mechanical ventilation in greater than or equal to 30% oxygen, and had radiographic evidence of bronchopulmonary dysplasia. The treatment group (n = 19) and the placebo group (n = 15) were similar in all respects except for distribution of gender. Anthropometrics, ventilatory measurements, and the results of pulmonary function tests were evaluated at study entry and at 1, 4, and 8 weeks into therapy. Poststudy chest radiographs were compared with those obtained before the study. The proportion of infants alive at discharge was significantly increased (84%) in the treatment group compared with the placebo group (47%) (p = 0.05). There were no statistically significant differences in total hospital days or in total ventilator days. Total respiratory system compliance at 4 weeks was higher in the treatment group (0.61 +/- 0.18) than in the placebo group (0.45 +/- 0.13) (p = 0.016). No difference in outcome was detected between male and female infants in the treatment group. These results suggest that long-term diuretic therapy improves outcome in infants with bronchopulmonary dysplasia. 相似文献
35.
Development of a high performance zinc-62/copper-62 radionuclide generator for positron emission tomography. 总被引:2,自引:0,他引:2
J Zweit R Goodall M Cox J W Babich G A Potter H L Sharma R J Ott 《European journal of nuclear medicine》1992,19(6):418-425
Clinical utilisation of positron emission tomography could be enhanced by the availability of short-lived radionuclides derived from generator systems. The zinc-62/copper-62 combination is one such system which could be used as a source for a number of copper-62 radiopharmaceuticals. We have developed and optimised a high activity (5.6 GBq, 150 mCi) zinc-62/copper-62 generator to provide 62Cu in a form that is suitable for direct labelling of pyruvaldehyde-bis-(N4-methylthiosemicarbazone)-copper(II), Cu(PTSM). The distribution coefficients of Zn(II) and Cu(II) between anion-exchange resin and various hydrochloric acid/organic solvent mixtures were measured. Based on these measurements a generator eluent of 0.3 M HCl/40% ethanol provided 62Cu in greater than 90% yield in a 3-ml volume. A very low 62Zn breakthrough of less than 3 x 10(-7)% was achieved. Copper-PTSM was successfully labelled with the no-carrier-added 62Cu eluent directly from the generator with 94% radiochemical yield. 相似文献
36.
37.
Water-suppressed 1H magnetic resonance spectra were recorded from two brain regions of psychiatric patients and normal volunteers. The two regions studied were (a) the basal ganglia structures surrounding the anterior horn of the lateral ventricle and (b) the occipital cortex. N-Acetylaspartate (NAA), phosphocreatine-creatine (PCr-Cr), choline and inositol resonances were seen in both regions. Ratios of metabolite peak integrals to PCr-Cr peak integral were calculated for each spectrum. To control for partial volume effects, comparisons between patients and controls were made only from identical regions i.e. basal ganglia vs basal ganglia, and likewise for occipital cortex. Metabolite ratios from the occipital region of patients were similar to those from the occipital region of normal subjects. Bipolar patients being treated with lithium had elevated NAA/PCr-Cr in the basal ganglia region when compared to normals. These patients also demonstrated elevated choline/PCr-Cr and inositol/PCr-Cr ratios in the basal ganglia region. 相似文献
38.
39.
N. C. Sharma R. Bhatia S. Singh P. C. John S. Kumar H. Singh 《Epidemiology and infection》1994,112(1):45-49
A total of 675 strains of Salmonella bareilly received from different parts of India and France during 1959-92 were phage typed using six bacteriophages. Overall typability achieved was 90.8% with 23 distinct phage types excluding a group of untypable strains. Phage types have been defined in octal code. Simpson''s coefficient was applied for diversity index having a value of 0.839. This system was found to be reproducible, stable and epidemiologically useful. 相似文献
40.
A study conducted in 1990 revealed that 2% (range 0.6-4.8) of negative blood smears were mislabelled as positive, and 6.7% of positive blood smears were mislabelled as negative. A result of such mislabelling would be inadequate treatment of a large number of patients. Hence the need to look into the training aspect and system of supervision of laboratory technicians. The present system of cross-checking of blood smears at different levels also needs to be reviewed. A study which could address itself to these needs is indicated. 相似文献