全文获取类型
收费全文 | 1735篇 |
免费 | 166篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 43篇 |
妇产科学 | 24篇 |
基础医学 | 326篇 |
口腔科学 | 39篇 |
临床医学 | 196篇 |
内科学 | 237篇 |
皮肤病学 | 33篇 |
神经病学 | 100篇 |
特种医学 | 95篇 |
外科学 | 264篇 |
综合类 | 125篇 |
一般理论 | 2篇 |
预防医学 | 90篇 |
眼科学 | 160篇 |
药学 | 100篇 |
肿瘤学 | 57篇 |
出版年
2021年 | 16篇 |
2019年 | 12篇 |
2018年 | 19篇 |
2016年 | 17篇 |
2015年 | 22篇 |
2014年 | 35篇 |
2013年 | 44篇 |
2012年 | 57篇 |
2011年 | 60篇 |
2010年 | 34篇 |
2009年 | 50篇 |
2008年 | 54篇 |
2007年 | 62篇 |
2006年 | 60篇 |
2005年 | 71篇 |
2004年 | 70篇 |
2003年 | 62篇 |
2002年 | 54篇 |
2001年 | 65篇 |
2000年 | 64篇 |
1999年 | 55篇 |
1998年 | 35篇 |
1997年 | 30篇 |
1996年 | 28篇 |
1995年 | 19篇 |
1994年 | 20篇 |
1993年 | 27篇 |
1992年 | 45篇 |
1991年 | 30篇 |
1990年 | 30篇 |
1989年 | 42篇 |
1988年 | 28篇 |
1987年 | 32篇 |
1986年 | 32篇 |
1985年 | 29篇 |
1984年 | 24篇 |
1983年 | 20篇 |
1982年 | 19篇 |
1981年 | 13篇 |
1979年 | 14篇 |
1978年 | 16篇 |
1977年 | 18篇 |
1976年 | 19篇 |
1975年 | 28篇 |
1974年 | 42篇 |
1973年 | 59篇 |
1972年 | 57篇 |
1971年 | 21篇 |
1970年 | 35篇 |
1967年 | 9篇 |
排序方式: 共有1904条查询结果,搜索用时 31 毫秒
31.
Safety and immunogenicity of meningococcal A and C polysaccharide conjugate vaccine in adults. 总被引:4,自引:7,他引:4
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E L Anderson T Bowers C M Mink D J Kennedy R B Belshe H Harakeh L Pais P Holder G M Carlone 《Infection and immunity》1994,62(8):3391-3395
A meningococcal vaccine containing group A and C polysaccharides conjugated to CRM197 was evaluated in 50 adults. Vaccinees were entered into one of five groups: 30 adults received a single dose of either 22, 11, or 5.5 micrograms of the conjugated A-C vaccine; 10 received an approved meningococcal vaccine; and 10 received saline injections. Local and systemic reactions to vaccines were recorded, and immune responses were determined. The experimental meningococcal vaccine was well tolerated, with the most frequent reaction being pain at the injection site. Both A and C polysaccharide components of the experimental vaccine were highly immunogenic, and total antibody concentrations 1 month postvaccination were not significantly different from the mean antibody concentrations among adults given the approved meningococcal vaccine. In addition, significant rises in immunoglobulin G, A, and M antibodies to both A and C polysaccharides occurred. Antibody concentrations measured at 6 and 12 months postvaccination had declined but remained significantly higher than prevaccination concentrations. Postvaccination meningococcal group C functional antibody activity increased more than 600-fold for both the polysaccharide and the conjugate vaccines. Further studies of this conjugated meningococcal vaccine are indicated for young children and infants. 相似文献
32.
Naturally acquired human antibodies which recognize the first epidermal growth factor-like module in the Plasmodium falciparum merozoite surface protein 1 do not inhibit parasite growth in vitro. 总被引:1,自引:1,他引:1
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Merozoite surface protein 1, one of the major surface proteins of the invasive blood stage of the malaria parasite, is a prime candidate for the development of a vaccine against the human disease. Previously, monoclonal antibodies which both inhibited the growth of Plasmodium falciparum in vitro and bound to the first of two epidermal growth factor-like modules located near the carboxy terminus of the protein had been identified. In this study, we have used affinity chromatography on a recombinant fusion protein corresponding to the first epidermal growth factor-like module in P. falciparum merozoite surface protein 1 to prepare antibody induced by natural infection. The antibody was purified from the total immunoglobulin G fraction of adult West African donors, shown to passively confer immunity against falciparum malaria. Such affinity-purified antibodies were shown to recognize the native protein by a number of separate criteria and to block the binding of an inhibitory monoclonal antibody, but they failed to inhibit parasite invasion in an in vitro growth assay. These results indicate that antibody alone is not sufficient to interfere with erythrocyte invasion. 相似文献
33.
G. E. Holder 《Documenta ophthalmologica. Advances in ophthalmology》1985,59(2):121-128
The potentials evoked by pattern reversal stimulation (2/sec, 11° field, 26 high contrast checks) are described in 22 patients with intracranial space-occupying lesions lying posterior to the optic chiasm. Seventeen (77%) of these patients had clinically demonstrable visual field defects. The nature and position of the lesion was defined by CT scan, by cerebral angiography, or at operation. Completely normal pattern visual evoked potentials (VEPs) were recorded in four patients (18%), all of whom had full visual fields. Definitely abnormal VEPs occurred in 12 patients (55%), 11 with visual field defects. The remaining six patients (27%), all with visual field defects, had VEPs that were inconsistently abnormal and they are rated as equivocal. The findings are discussed with particular attention to the importance of stimulus and recording parameters. 相似文献
34.
Canent RV Anthony PJ Holder TM Ashcraft KW 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》1987,14(3):300-306
When corrective surgery for tetralogy of Fallot was accomplished through the use of a transannular GORE-TEX patch with a pericardial unicusp, the right-ventricular end-diastolic volumes of all patients studied within a year of the surgery were within the normal ranges because of decreased pulmonary valve regurgitation. The right-ventricular ejection fraction was also only slightly depressed, indicating preservation of right-ventricular function. All patients were noted to maintain normal stroke volumes and normal systolic indices. In contrast, the patients who had transannular patches placed without unicusps showed significantly elevated right-ventricular end-diastolic volumes and lower right-ventricular ejection fractions. These resulted from markedly dilated right-ventricular outflow regions in conjunction with enlarged right-ventricular chambers, which manifested as large dyskinetic areas in the anterior right-ventricular walls. 相似文献
35.
The specific scintigraphic pattern of "shin splints in the lower leg": concise communication 总被引:1,自引:0,他引:1
The clinical entity, "shin splints," is now being recognized, and more specifically characterized by the findings of exercise-induced pain and tenderness to palpation along the posterior medial border of the tibia. In this prospective study, ten patients with this syndrome were evaluated using three-phase bone scintigrams, and a specific scintigraphic pattern was determined. Radionuclide angiograms and blood-pool images were all normal. On delayed images, tibial lesions involved the posterior cortex, were longitudinally oriented, were long, involving one third of the length of the bone, and often showed varying tracer uptake along that length. Obtaining both lateral and medial views was crucial. The location of activity suggested that this entity is related to the soleus muscle. These scintigraphic findings can be used to differentiate shin splints from stress fractures or other conditions causing pain in the lower leg in athletes. 相似文献
36.
37.
Parent Involvement in Cigarette Smoking Prevention: Two Pilot Evaluations of the "Unpuffables Program" 总被引:1,自引:0,他引:1
Efforts to prevent the onset of cigarette smoking with young adolescents have been primarily successful in delaying onset, particularly with classroom curricula that emphasize social competencies. Maintenance of these reductions has been difficult to sustain into later adolescence, suggesting the need for programs to complement and supplement curricula. Since one group of adolescents more difficult to influence are those whose parents smoke, parental involvement in smoking prevention may be a powerful enhancer. This paper describes the "Unpuffables Program," an activity package program around smoking, for preadolescents and their parents. Two pilot evaluation studies in Minnesota and Massachusetts focus on the feasibility of and receptivity to the "Unpuffables Program." High awareness and participation rates were found in both settings. The program appears to provide an opportunity for smoking to be discussed at home, motivating smokers to consider cessation, and reinforcing nonsmoking parents' attitudes and behaviors. 相似文献
38.
Parameters affecting cellular adhesion to polylactide films 总被引:1,自引:0,他引:1
Burg KJ Holder WD Culberson CR Beiler RJ Greene KG Loebsack AB Roland WD Mooney DJ Halberstadt CR 《Journal of biomaterials science. Polymer edition》1999,10(2):147-161
Absorbable biomaterials have been recently incorporated into the field of tissue engineering. Little work has been performed, even with the clinically acceptable absorbables, concerning their tissue promoting capability or lack, thereof. Furthermore, the relative attractions of cells to these implants may be largely disguised by the presence of serum. This research involved the development of an adhesion assay to compare the adhesion behavior of two cell types to two different polylactides in a serum free environment. The results showed that the attachment behavior depends not only on the cell or the polymer but a combination of the two. 相似文献
39.
Antimicrobial resistance 总被引:1,自引:0,他引:1
40.
Mice fed 0 serotype-specific strains of P. aeruginosa for two weeks, had increased titers of IgM but not IgG antibodies to the strains fed. Immunized mice, burned and infected with P. aeruginosa, showed significant 0 serotype-specific enhanced survival. Survival of mice fed several 0 serotype-specific strains simultaneously increased when these mice were burned and infected with P. aeruginosa homologous to those fed except when a high exotoxin A producing strain was used. Mice fed purified exotoxin A showed an increased LD50 when injected with graded toxin doses. Feeding both 0 serotype-specific P. aeruginosa plus exotocin A increased survival even with burn and infection using the high toxin producing strain. We conclude that feeding P. aeruginosa antigens provides successful immunization which avoids the effects of parental adminstration. 相似文献