全文获取类型
收费全文 | 721篇 |
免费 | 56篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 41篇 |
妇产科学 | 4篇 |
基础医学 | 92篇 |
口腔科学 | 12篇 |
临床医学 | 77篇 |
内科学 | 201篇 |
皮肤病学 | 16篇 |
神经病学 | 11篇 |
特种医学 | 117篇 |
外科学 | 39篇 |
综合类 | 106篇 |
预防医学 | 29篇 |
眼科学 | 2篇 |
药学 | 20篇 |
中国医学 | 1篇 |
肿瘤学 | 21篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 10篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 8篇 |
2016年 | 12篇 |
2015年 | 19篇 |
2014年 | 25篇 |
2013年 | 19篇 |
2012年 | 30篇 |
2011年 | 20篇 |
2010年 | 33篇 |
2009年 | 37篇 |
2008年 | 40篇 |
2007年 | 36篇 |
2006年 | 18篇 |
2005年 | 17篇 |
2004年 | 12篇 |
2003年 | 18篇 |
2002年 | 16篇 |
2001年 | 21篇 |
2000年 | 12篇 |
1999年 | 23篇 |
1998年 | 48篇 |
1997年 | 40篇 |
1996年 | 31篇 |
1995年 | 21篇 |
1994年 | 27篇 |
1993年 | 23篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 15篇 |
1988年 | 12篇 |
1987年 | 25篇 |
1986年 | 9篇 |
1985年 | 13篇 |
1984年 | 4篇 |
1983年 | 7篇 |
1982年 | 15篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1979年 | 2篇 |
1978年 | 8篇 |
1977年 | 4篇 |
1976年 | 8篇 |
1975年 | 5篇 |
1967年 | 1篇 |
排序方式: 共有793条查询结果,搜索用时 31 毫秒
81.
The mouse monoclonal antibody M2A1 of IgG1 class, which is highly specific for blood group M antigen, was obtained and characterized by means of hemagglutination, enzyme-linked immunosorbent assay, immunoblotting, and inhibition assays. The use of modified M glycoprotein preparations for inhibition tests and of variant McN and Henshaw red cell membranes for immunoblotting showed that M2A1 recognized an epitope including the NH2-terminal serine and sialic acid residues of glycophorin A, whereas the fifth glycine residue was not involved. The reactivity of the antibody with M antigen was distinctly dependent on ionic strength and pH; the optimum was at pH 8 to 9. The alpha-amino group of terminal serine residue was not necessary for the reaction with M2A1 antibody, and the results obtained suggested that the positive charge of this group contributed to decreasing antigen-antibody reactions at pH below 8. The reaction of the antibody with blood group N antigen was not detectable in any of the assays used. 相似文献
82.
MATÍAS PÉREZ-PAREDES FRANCISCO PICÓ-ARACIL RAFAEL FLORENCIANO JOSÉ G. SÁNCHEZ-VILLANUEVA JOSÉ ANTONIO RUIZ ROS JUAN A. RUIPÉREZ 《Pacing and clinical electrophysiology : PACE》1999,22(8):1173-1178
This study was designed to examine the "true sensitivity" of a specific head-up tilt (HUT) testing protocol using clinical findings. The HUT protocol used 45 minutes at 60 degrees for the baseline portion and intermittent boluses of 2, 4, and 6 micrograms of isoproterenol in the second phase. Eighty-eight patients (40 men and 48 women; mean age of 33.8 +/- 16 years) with recurrent syncope and high pretest likelihood of neurally mediated syncope were included. The following were considerated as high pretest likelihood criteria: (1) at least two syncopal episodes; (2) no structural heart disease and normal baseline ECG; (3) age < 65 years; (4) a typical history of neurally mediated syncope, triggering factors plus premonitory signs; and (5) short duration of symptoms and fast recovery without neurological sequelae. Fifty-four patients (61%) had a positive tilt test (34/88 baseline [39%] and 20/50 with isoproterenol [40%]). The shorter time interval between the last syncopal episode and baseline HUT test was the only predictor for a positive response (P < 0.003). Conversely, this time interval was not predictor of positive responses during isoproterenol-tilt testing. In conclusion: (1) we claim a "sensitivity" for this combined protocol of 61%; and (2) our results indicate that patients with syncope of unknown origin must be tilted nearest as possible to the last syncope to increase the positive responses of HUT test. 相似文献
83.
84.
85.
India has a high prevalence of diabetes mellitus and the numbers are increasing at an alarming rate. In India alone, diabetes is expected to increase from 40.6 million in 2006 to 79.4 million by 2030. Studies have shown that the prevalence of diabetes in urban Indian adults is about 12.1%, the onset of which is about a decade earlier than their western counterparts and the prevalence of Type 2 diabetes is 4–6 times higher in urban than in rural areas. The risk factors peculiar for developing diabetes among Indians include high familial aggregation, central obesity, insulin resistance and life style changes due to urbanization. Screening for gestational diabetes and impaired glucose tolerance among pregnant women provides a scope for primary prevention of the disease in mothers as well as in their children. The problems of obesity and impaired glucose tolerance (IGT) (important predisposing factors) are not confined to adults alone but children are also increasingly getting affected. Most long standing macro and micro vascular complications are also more common among Indian diabetics as compared to other races and ethnic groups. A strong familial clustering of diabetic nephropathy among Indian Type 2 diabetics has also been noted. Clustering of cardiovascular risk factor like Syndrome X is common among urban Indians. The rising incidence of diabetes and its complications are going to pose a grave health care burden on our country. Timely effective interventions/measures and screening tests for complications at the time of diagnosis becomes imperative not only for early detection, but also to prevent progression to end stage disease. Screening for gestational diabetes among pregnant women would also go a long way in primary prevention of the disease. Life style changes/interventions and drugs like rosiglitazone are the current strategies that can prevent and/or delay the onset of diabetes. Simple interventional strategies like “Eat less, Eat on time and Walk more” can go a long way in preventing these chronic disorders among present as well as in the future generations. 相似文献
86.
87.
Background
A spinal cord injury is devastating and produces profound changes in the life style of the individual and his family. It is difficult to predict bladder and sphincter behaviour on the basis of clinical somatic neurological deficits.Methods
A prospective study of 100 spinal cord injury patients was conducted to establish a bladder management protocol. The urodynamic variables were assessed frequently. Clean Intermittent Catheterization (CIC) along with antimuscarinic drugs was instituted and response monitored. Nonresponders were offered Intradetrusor Botulinum toxin.Result
Spinal shock lasted for upto six months and only 8% could be converted to CIC during the acute phase. A total of 82% patients underwent three to four urodynamic studies which revealed an increase in cystometric capacity and a decrease in the maximum detrusor pressures. This lowered the incidence of incontinence episodes and prevented upper urinary tract damage. Botulinum toxin provided only temporary relief.Conclusion
Aggressive management of neurogenic bladder (NB) dysfunction is a crucial component of the rehabilitation programme for spinal cord injury patients. Repeated urodynamic studies are an essential aid in managing the evolving nature of the bladder dysfunction. Meticulous bladder management protocol can prevent upper urinary tract complications.Key Words: Spinal cord injury, Neurogenic bladder, Urodynamics 相似文献88.
Chen HY Di Mascio M Perelson AS Ho DD Zhang L 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(48):19079-19084
A single-cycle simian immunodeficiency virus (scSIV) that undergoes only one round of infection and replication was constructed to calculate the total number of virons produced by an SIV-infected cell in vivo. Four Mamu-A*01 rhesus macaques were inoculated on two occasions 11 weeks apart with the scSIV by ex vivo infection and i.v. reinfusion of autologous cells. After each inoculation, plasma viral loads peaked between 1 and 2.5 days and then declined exponentially in one or two phases to below detection limits within 2 weeks. Although higher levels of SIV-specific cytotoxic T lymphocytes and modest increases in antibody responses were observed for each animal after the second inoculation, decay rates of the infected cells were only minimally affected. Analyzing the viral load data with a mathematical model, the in vivo viral burst size averaged 4.0 x 10(4) and 5.5 x 10(4) virions per cell for the first and second inoculations, respectively, with no significant difference between the two inoculations. This estimate, in conjunction with our prior understanding of other quantitative viral and cellular parameters during SIV and HIV infection, provides critical insights into the dynamic process of viral production and its interplay with the infected host in vivo. 相似文献
89.
RL Broadhead AS Muula 《Malawi medical journal : the journal of Medical Association of Malawi》2001,13(3):6-10
Ten years have now passed since the College of Medicine of the University of Malawi was opened. The College''s Curriculum is firmly based on community needs. We describe the genesis and implementation of the curriculum of the College of Medicine and how it has persisted over the past ten years. The challenges that have so far been met are outlined. 相似文献
90.
Surgical bacterial infections and antimicrobial susceptibility patterns at Lilongwe Central Hospital
RM Banda AS Muula GR Gwaza DC Namarika KC Ng'oma FE Chintolo H Yamakazi AP Muyco 《Malawi medical journal : the journal of Medical Association of Malawi》2001,13(3):27-29
A cross sectional study was done between October 1999 and February 2000 to determine antimicrobial susceptibility patterns of consecutive bacterial isolates of 102 clinical samples among surgical in-patients at Lilongwe Central Hospital (LCH), Malawi. Antimicrobial susceptibility was determined using comparative disc diffusion techniques. 83 (81.4%) samples were culture positive for bacterial growth while 19 (18.6%) grew nothing. Of the 93 culture positive specimens, Staphylococcus aureus was the predominant organism 43(51.8%) followed by Proteus species 8(9.6%) and E. coli 7(8.4%). Overall, 98.6% of all isolates tested against ciprofloxacin were susceptible, and against gentamicin and flucloxacin were 84.8% and 66.7% respectively. 59.3% of isolates tested against chloramphenicol were resistant. We recommend a review on the use of chloramphenicol as first-line antimicrobial therapy among surgical in-patients at Lilongwe Central Hospital. We also recommend restricted use of antimicrobials so as to minimise development of drug resistance. Periodic susceptibility studies are necessary to guide judicious use of antibiotics. 相似文献