全文获取类型
收费全文 | 2696篇 |
免费 | 168篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 130篇 |
妇产科学 | 77篇 |
基础医学 | 439篇 |
口腔科学 | 103篇 |
临床医学 | 205篇 |
内科学 | 509篇 |
皮肤病学 | 24篇 |
神经病学 | 178篇 |
特种医学 | 88篇 |
外科学 | 282篇 |
综合类 | 76篇 |
一般理论 | 1篇 |
预防医学 | 327篇 |
眼科学 | 45篇 |
药学 | 146篇 |
中国医学 | 6篇 |
肿瘤学 | 248篇 |
出版年
2023年 | 17篇 |
2022年 | 34篇 |
2021年 | 77篇 |
2020年 | 48篇 |
2019年 | 52篇 |
2018年 | 77篇 |
2017年 | 70篇 |
2016年 | 63篇 |
2015年 | 56篇 |
2014年 | 83篇 |
2013年 | 124篇 |
2012年 | 136篇 |
2011年 | 148篇 |
2010年 | 106篇 |
2009年 | 103篇 |
2008年 | 135篇 |
2007年 | 143篇 |
2006年 | 155篇 |
2005年 | 162篇 |
2004年 | 114篇 |
2003年 | 85篇 |
2002年 | 78篇 |
2001年 | 78篇 |
2000年 | 85篇 |
1999年 | 70篇 |
1998年 | 43篇 |
1997年 | 33篇 |
1996年 | 38篇 |
1995年 | 27篇 |
1994年 | 35篇 |
1993年 | 27篇 |
1992年 | 49篇 |
1991年 | 36篇 |
1990年 | 34篇 |
1989年 | 41篇 |
1988年 | 34篇 |
1987年 | 22篇 |
1986年 | 26篇 |
1985年 | 20篇 |
1984年 | 8篇 |
1983年 | 11篇 |
1982年 | 9篇 |
1981年 | 13篇 |
1980年 | 7篇 |
1979年 | 6篇 |
1978年 | 6篇 |
1977年 | 10篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1967年 | 6篇 |
排序方式: 共有2895条查询结果,搜索用时 15 毫秒
11.
12.
This paper describes the results of an asthma self-management protocol delivered to parents of children aged 0-4 years. The protocol was delivered by general practitioners (GPs), community nurses, asthma nurses, and doctors in child health centers. It consisted of 16 educational modules developed after an initial needs assessment of parents and a task analysis of primary care practitioners. The program was evaluated by means of an experimental design. Parents participating in the program had significantly more knowledge, a more favorable attitude toward asthma, and a higher self-efficacy score with respect to performing asthma self-management behaviors. Also, they reported performing self-management behaviors more frequently than parents in the control group. One-year follow-up results, which were collected for parents in the treatment group only, showed that the described changes were sustained. Further, the treatment group was found to have decreased its emergency and nonemergency use of the physician's office and to have a reduction in (reported) asthma severity. Process evaluation indicated that most modules were provided by the GPs to nearly all parents. After parents had read the modules at home, almost all the information was discussed in the next contact. GPs seldom referred patients to the community nurses, although this was suggested in the protocol. 相似文献
13.
Inhibition of neutrophil and eosinophil induced chemotaxis by nedocromil sodium and sodium cromoglycate. 总被引:4,自引:2,他引:2 下载免费PDF全文
P. L. Bruijnzeel R. A. Warringa P. T. Kok J. Kreukniet 《British journal of pharmacology》1990,99(4):798-802
1. Neutrophils and eosinophils infiltrate the airways in association with the allergen-induced late phase asthmatic reaction. Mobilization of these cells takes place via lipid-like and protein-like chemotactic factors. In this study platelet-activating factor (PAF), leukotriene B4 (LTB4), zymosan-activated serum (ZAS) and N-formyl-methionyl-leucyl-phenylalanine (FMLP) were used as illustrative examples of both groups. Chemotaxis was studied in human neutrophils and eosinophils. The inhibitory effects of nedocromil sodium and sodium cromoglycate were evaluated. 2. All chemotactic factors tested attracted neutrophils with the following rank order of activity: ZAS greater than PAF identical to FMLP identical to LTB4. Eosinophils were only mobilized by PAF, LTB4 and ZAS with the following rank order of activity: ZAS greater than PAF greater than LTB4. 3. Nedocromil sodium and sodium cromoglycate were equally active as the PAF antagonist BN 52021 in inhibiting the PAF-induced chemotaxis of neutrophils (IC50 approximately 10(-8) M). Both drugs were also equally active in inhibiting the chemotaxis of neutrophils induced by ZAS (IC50 approximately 10(-7)-10(-6) M), FMLP (IC50 approximately 10(-7) M) and LTB4 (IC50 approximately 10(-6) M). 4. Nedocromil sodium significantly inhibited the chemotaxis of eosinophils induced by PAF (IC50 approximately 10(-6) M) and LTB4 (IC50 approximately 10(-7) M). The inhibitory potency of BN 52021 was similar to that of nedocromil sodium on the PAF-induced chemotaxis of eosinophils. Sodium cromoglycate was incapable of eliciting significant inhibition of these chemotactic responses. However, sodium cromoglycate significantly inhibited the chemotaxis of eosinophils induced by ZAS (IC50 approximately 10(-7) M), whereas nedocromil sodium was ineffective. 相似文献
14.
L M Bouter O J van Rijn G Kok 《Burns : journal of the International Society for Burn Injuries》1990,16(3):198-202
The planning of health education in the prevention of burn injuries is typically incomplete and not stated explicitly, while the evaluation is executed only partially or is altogether non-existent. This article presents a theoretical framework for planning and evaluating health education for those at risk for burns. Systematic planning consists of an assessment of the magnitude and severity of the problem, an analysis of the behavioural risk factors, a study of the determinants of the most risky modes of behaviour, the design of an optimal intervention, and the implementation of this intervention. The evaluation phase deals with the effects on these five levels (implementation, intervention, determinants, behaviour and injury risk). Some common pitfalls are mentioned and special attention is given to the study of determinants of behaviour and to the design of the intervention. Furthermore, the importance of pretesting health education material is underlined. There appears to be a strong need for further research on the aetiology of burn injury and the relevant determinants of behaviour, before effective prevention can be realized. 相似文献
15.
Penile studies and heterosexual partners. Peniscopy, cytology, histology, and immunocytochemistry 总被引:2,自引:0,他引:2
M E Boon A Schneider C J Hogewoning T H van der Kwast P Bolhuis L P Kok 《Cancer》1988,61(8):1652-1659
The male partners of 20 women with human papilloma virus (HPV) infection (subtypes 6, 11, 16, and 18) were studied. These men were unsuspecting and allowed investigation "for scientific reasons" in the context of the abnormal findings in their female partners. Peniscopy (study of the penis with a colposcope) was abnormal in 17 cases. In the cytologic-brush preparations of the urethra, hyperkeratosis (visualized with the modified Papanicolaou technique) occurred in all cases, but koilocytosis in only one. Both urothelial cells and squamous cells in the urethral samples were positive for HPV, as shown in the immunocytochemistry. In the histologic sections taken from flat lesions there was hyperkeratosis, dyskeratosis, and abnormal nuclear maturation. The authors concluded that, using simple techniques, subtle disturbances in maturation of nuclei and cytoplasm can be established in penile epithelium of these sexual partners. Similar changes are established in other HPV lesions. It seems likely that a significant proportion of the male population is infected in countries were HPV an important factor in cervical carcinogenesis. 相似文献
16.
Kok Yvette J.M.de; Merkx Gerard F.M.; van der Maarel Silvere M.; Huber Irene; Malcolm Susan; Ropers Hans-Hilger; Cremers Frans P.M. 《Human molecular genetics》1995,4(11):2145-2150
X-linked deafness with stapes fixation (DFN3) is caused by mutationsin the POU3F4 gene at Xq21.1. By employing pulsed field gelelectrophoresis (PFGE) we identified a chromosomal aberrationin the DNA of a DFN3 patient who did not show alterations inthe open reading frame (ORF) of POU3F4. Southern blot analysisindicated that a DNA segment of 150 kb, located 170 kb proximalto the POU3F4 gene, was duplicated. Fluorescence in situ hybridization(FISH) analysis, PFGE, and detailed Southern analysis revealedthat this duplication is part of a more complex rearrangementincluding a paracentric inversion involving the Xq21.1 region,and presumably the Xq21.3 region. Since at least two DFN3-associatedminideletions are situated proximal to the duplicated segment,the inversion most likely disconnects the POU3F4 gene from aregulatory element which is located at a distance of at least400 kb upstream of the POU3F4 gene. 相似文献
17.
Rajendranath Ramasawmy Meera Manraj Navaratnam Kotea Nathalie Kok Shun Emmanuelle Genin Josué Feingold Rajagopal Krishnamoorthy Sooriahnarain Baligadoo 《Clinical genetics》1996,50(6):551-554
Eighty-five young Mauritian Indians, male survivors of premature myocardial infarction (MI) and thus belonging to a high risk group, were compared with 108 stringently selected controls for a possible association between premature MI and an insertion/deletion (I/D) polymorphism in the gene encoding angiotensin I-converting enzyme (ACE). The frequency of the D allele was 0.42 in the MI group and 0.43 in the control group, and thus no association between I/D polymorphism of ACE with susceptibility to early-onset MI was found in this population group. Other gene components of the renin-angiotensin system and lipid metabolism need to be explored to understand the genetic factors involved in causing MI at an early age. 相似文献
18.
19.
X-linked mixed deafness (DFN3): cloning and characterization of the critical region allows the identification of novel microdeletions 总被引:5,自引:0,他引:5
Huber Irene; Bitner-Gllndzicz Maria; de Kok Yvette J.M.; van der Maarel Silvere M.; Ishikawa-Brush Yumiko; Monaco Anthony P.; Robinson David; Malcolm Susan; Pembrey Marcus E.; Brunner Han G.; Cremers Frans P.M.; Ropers Hans-Hilger 《Human molecular genetics》1994,3(7):1151-1154
We have found that the microsatellite marker AFM207zg5 (DXS995)maps to all previously described deletions which are associatedwith X-linked mixed deafness (DFN3) with or without choroideremiaand mental retardation. Employing this marker and pHU16 (DXS26)we have identified two partially overlapping yeast artificialchromosome clones which were used to construct a complete 850kb cosmid contig. Cosmids from this contig have been testedby Southern blot analysis on DNA from 16 unrelated males withX-linked deafness. Two novel microdeletions were detected inpatients which exhibit the characteristic DFN3 phenotype. Bothdeletions are completely contained within one of the known DFN3-deletions,but one of them does not overlap with two previously describeddeletions in patients with contiguous gene syndromes consistingof DFN3, chorolderemia, and mental retardation. Assuming thatonly a single gene is involved, this suggests that the DFN3gene spans a chromosomal region of at least 400 kb. 相似文献
20.
doublecortin is the major gene causing X-linked subcortical laminar heterotopia (SCLH) 总被引:12,自引:0,他引:12
des Portes V; Francis F; Pinard JM; Desguerre I; Moutard ML; Snoeck I; Meiners LC; Capron F; Cusmai R; Ricci S; Motte J; Echenne B; Ponsot G; Dulac O; Chelly J; Beldjord C 《Human molecular genetics》1998,7(7):1063-1070
Subcortical laminar heterotopia (SCLH), or 'double cortex', is a cortical
dysgenesis disorder associated with a defect in neuronal migration.
Clinical manifestations are epilepsy and mental retardation. This disorder,
which mainly affects females, can be inherited in a single pedigree with
lissencephaly, a more severe disease which affects the male individuals.
This clinical entity has been described as X- SCLH/LIS syndrome. Recently
we have demonstrated that the doublecortin gene, which is localized on the
X chromosome, is implicated in this disorder. We have now performed a
systematic mutation analysis of doublecortin in 11 unrelated females with
SCLH (one familial and 10 sporadic cases) and have identified mutations in
10/11 cases. The sequence differences include nonsense, splice site and
missense mutations and these were found throughout the gene. These results
provide strong evidence that loss of function of doublecortin is the major
cause of SCLH. The absence of phenotype-genotype correlations suggests that
X-inactivation patterns of neuronal precursor cells are likely to
contribute to the variable clinical severity of this disorder in females.
相似文献