全文获取类型
收费全文 | 1442篇 |
免费 | 89篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 32篇 |
妇产科学 | 39篇 |
基础医学 | 246篇 |
口腔科学 | 27篇 |
临床医学 | 156篇 |
内科学 | 259篇 |
皮肤病学 | 38篇 |
神经病学 | 122篇 |
特种医学 | 17篇 |
外科学 | 189篇 |
综合类 | 9篇 |
预防医学 | 133篇 |
眼科学 | 29篇 |
药学 | 112篇 |
中国医学 | 4篇 |
肿瘤学 | 119篇 |
出版年
2023年 | 10篇 |
2022年 | 14篇 |
2021年 | 26篇 |
2020年 | 18篇 |
2019年 | 27篇 |
2018年 | 34篇 |
2017年 | 30篇 |
2016年 | 29篇 |
2015年 | 37篇 |
2014年 | 62篇 |
2013年 | 60篇 |
2012年 | 96篇 |
2011年 | 107篇 |
2010年 | 58篇 |
2009年 | 51篇 |
2008年 | 117篇 |
2007年 | 97篇 |
2006年 | 96篇 |
2005年 | 84篇 |
2004年 | 91篇 |
2003年 | 86篇 |
2002年 | 70篇 |
2001年 | 10篇 |
2000年 | 19篇 |
1999年 | 15篇 |
1998年 | 14篇 |
1997年 | 10篇 |
1996年 | 14篇 |
1995年 | 9篇 |
1994年 | 9篇 |
1993年 | 12篇 |
1992年 | 5篇 |
1990年 | 10篇 |
1989年 | 11篇 |
1987年 | 6篇 |
1984年 | 4篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 8篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1970年 | 6篇 |
1969年 | 3篇 |
排序方式: 共有1542条查询结果,搜索用时 15 毫秒
1.
Manuel Steiner Andishe Attarbaschi Margit K nig Helmut Gadner Oskar A. Haas Georg Mann 《Pediatric hematology and oncology》2004,22(1):11-16
Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposing factor. 相似文献
2.
Growth and invasion of human melanomas in human skin grafted to immunodeficient mice. 总被引:8,自引:3,他引:5
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
I. Juhasz S. M. Albelda D. E. Elder G. F. Murphy K. Adachi D. Herlyn I. T. Valyi-Nagy M. Herlyn 《The American journal of pathology》1993,143(2):528-537
An orthotopic model of human melanoma was developed in which malignant cells were injected into human skin grafted to nude and SCID mice. Melanoma cells proliferated and invaded the human skin grafts with characteristic patterns. Three of six melanomas grew as multiple nodules and infiltered the grafts without major architectural changes in the dermis, whereas the others invaded the dermis along collagen fibers with prominent endothelial vessels. By contrast, melanoma cells inoculated into mouse skin grew as diffusely expanding nodules that did not invade the murine dermis. In human skin grafts, human melanoma cells were angiogenic for human blood vessels, and murine vessels were only found at the periphery of grafts. Tumor cells invaded the human vessels, and four out of seven cell lines metastasized to lungs, suggesting that this model is useful to determine in vivo the interactions between normal and malignant human cells. 相似文献
3.
B.E. Jones C.B. Boylan M. Fritsche M. Juhasz C. Jackson S.J. Wiegand C. Hyman R.M. Lindsay C.A. Altar 《Brain research》1996,709(2):275
Rat models of Parkinson's disease typically employ a rapid nigral injection of 6-hydroxydopamine (6-OHDA) to produce a near-complete loss of nigrostriatal dopamine neurons, and thus model end stage disease. The present report describes the use of a continuous, low dose infusion of 6-OHDA into the striatum which produces a terminal axotomy of nigrostriatal dopamine neurons and protracted behavioral response. A solution of 6-OHDA in 0.4% ascorbate, delivered at 37°C from osmotic minipumps, was stable for 8 days as determined by its retained toxicity to a dopaminergic neuroblastoma cell line. The continuous infusion of 0.2 μg 6-OHDA per h did not affect the striatal uptake of [3H]GABA, [3H]choline, or [3H]glutamate but reduced [3H]dopamine uptake by 55% within 1.5 days after the start of the infusion. The striatal infusion of 6-OHDA produced a dose-dependent reduction of striatal dopamine and DOPAC levels but did not alter HVA, 5-HT, or 5-HIAA. An increase in amphetamine-induced ipsiversive rotations occurred within 1.5 days after the acute striatal injection of 20 μg or 30 μg of 6-OHDA but required 4 days to develop with the continuous 6-OHDA infusion. The topography of the lesion mapped by [3H]mazindol binding showed that, begining by 1.5 days, a diffuse depletion of terminals encompassed much of the striatum in the 30 μg acute injection group, whereas in the continuously infused rats, the lesion was apparent only by 4 days and was restricted to a smaller and more completely lesioned area. Unlike acutely lesioned animals, continuously infused rats revealed no obvious loss of dopamine neurons in the pars compacta by 5 weeks after 6-OHDA. The continuous striatal infusion of 6-OHDA can produce a topographically limited terminal axotomy of dopamine neurons and a protracted behavioral impairment. 相似文献
4.
Ulla Christensen Lone Schmidt Charlotte ?rsted Hougaard Margit Kriegbaum Bj?rn Evald Holstein 《Journal of rehabilitation medicine》2006,38(5):316-321
OBJECTIVE: To examine the association between socioeconomic position and coping strategies in musculoskeletal pain. DESIGN AND SUBJECTS: Cross-sectional study of a random sample of 40- and 50-year-old Danes, participation rate 69%, n=7,125. The study included 1,287 persons who reported functional limitations due to musculoskeletal pain. METHODS: Data was collected by postal questionnaires and scales were developed on problem-solving coping and avoidant coping, based on a range of preliminary studies. Multivariate logistic regression analyses was used to study the correlation with socioeconomic position, measured by occupational social class. RESULTS: Among women, there was no correlation between social class and avoidant coping, but a significant decrease in the use of problem-solving coping by decreasing social class, adjusted odds ratio (OR) = 2.64 (95% confidence interval (CI) 1.31-5.32) in social class V vs social classes I + II. Among men, there was no correlation between social class and problem-solving coping, but a significant increase in the use of avoidant coping with decreasing social class, adjusted OR = 3.31 (95% CI 1.75-6.25) in V vs I + II. CONCLUSION: It is important for clinicians who advise and support patients in their response to musculoskeletal pain to be aware of socioeconomic differences in coping strategies. Gender differences in the association between socioeconomic factors and coping should be further investigated. 相似文献
5.
Krisztina Bencsik Judit Füvesi Zsanett Fricska-Nagy Cecília Rajda Erika Losonczi Margit T?r?k László Vécsei 《Journal of interferon & cytokine research》2006,26(2):96-100
The first pharmacon with proved efficacy for the treatment of patients with the relapsing-remitting or relapsing-progressive form of multiple sclerosis (MS) was interferon-beta1b (IFN-beta1b). In 1996, we started treating 34 relapsing-remitting (RRMS) and 2 relapsing-progressive MS (RPMS) patients with IFN-beta1b. Of these 36 patients, 28 received continuous medication for 6 years. The primary end point of the study was the effect of 6 years of continuous IFN-beta1b treatment on the annual relapse rate, the secondary end point was the change in the progression index during the 6 years, and the tertiary end point was the alteration in the expanded disability status scale (EDSS) score of the patients. Finally, we give the reasons for the dropouts. The relapse rate decreased by 80.62% (p < 0.001), the mean EDSS score increased significantly, by approximately 0.5 points, to 2.21 +/- 1.48 (p = 0.016), and the reduction in the mean progression index was 67.19% (p < 0.001). This increase of < 0.5 point in the EDSS score is appreciably different from the 3-point deterioration expected after 6 years for the natural course of the disease. The significant improvement in the progression index clearly demonstrates that 6 years of IFN-beta1b therapy slowed the progression of the disease, thereby improving the quality of life of these MS patients. 相似文献
6.
Mass spectrometric molecular-weight determination of highly acidic compounds of biological significance via their complexes with basic polypeptides. 总被引:3,自引:0,他引:3
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
P Juhasz K Biemann 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(10):4333-4337
Highly acidic compounds that are difficult to ionize by matrix-assisted laser desorption ionization give excellent spectra when mixed with a basic peptide or protein to form a noncovalent complex. This phenomenon makes it possible to determine the molecular weights of polysulfated, -sulfonated, and -phosphorylated biomolecules such as cysteic acid-containing peptides, oligonucleotides, heparin-derived oligosaccharides, and suramin (a drug containing two trisulfonated naphthalene moieties). Peptides and small proteins rich in arginine were used as the basic components. The extent of complex formation correlates with the number of phosphate and sulfate groups in the acidic component and with the number of arginines in the basic component. Neither the acidic amino acid residue aspartic and glutamic acid nor the basic lysine and histidine contribute to complex formation. For oligonucleotides, histone H4 was found to be the best complexing agent investigated. The analytical utility of the complex formation is demonstrated by the molecular-mass determination of acidic compounds from 500 to 6000 Da at the picomole or sub-picomole level with an accuracy of +/- 0.1% or better and by the absence of alkali cation adducts. 相似文献
7.
John F. Fraser MBChB ; Leila Cuttle BSc ; Margit Kempf BmedLSci ; Gael E. Phillips MBBS ; Peter K. O'Rourke PhD ; Kelvin Choo MBBS ; Mark T. Hayes PhD ; Roy M. Kimble MBChB 《Wound repair and regeneration》2005,13(2):189-197
Early to mid-term fetuses heal cutaneous incisional wounds without scars; however, fetal response to burn injury has not been ascertained. We present a fetal model of thermal injury and subsequent analysis of fetal and lamb response to burn injury. A reproducible deep dermal burn injury was created in the fetus by application of water at 66 degrees C for 7 seconds, and at 82 degrees C for 10 seconds to the lamb. Macroscopically, the area of fetal scald was undetectable from day 7 post injury, while all lamb scalds were readily identified and eventually healed with scarring. Using a five-point histopathology scoring system for alteration in tissue morphology, differences were detected between control and scalded skin at all stages in lamb postburn, but no difference was detected in the fetal model after day 7. There were also large differences in content of alpha-smooth muscle actin and transforming growth factor-beta1 between control and scalded lamb and these differences were statistically significant at day 14 (P < 0.01). This novel model of fetal and lamb response to deep dermal injury indicates that the fetus heals a deep burn injury in a scarless fashion. Further elucidation of this specific fetal process of burn injury repair may lead to improved outcome for patients with burn injury. 相似文献
8.
Ohne Zusammenfassung 相似文献
9.
Füst G Arason GJ Kramer J Szalai C Duba J Yang Y Chung EK Zhou B Blanchong CA Lokki ML Bödvarsson S Prohászka Z Karádi I Vatay A Kovács M Romics L Thorgeirsson G Yu CY 《International immunology》2004,16(10):1507-1514
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking. 相似文献
10.
Danish nationwide surveillance data on invasive pneumococcal disease from the 5-year period from 1995 to 1999, including 5,452 isolates, are presented and described. Annual overall incidence rates, serotype distribution, and antimicrobial susceptibility patterns of the isolates were monitored. Major changes in the total annual incidence rate from 27/100,000 in 1996 to 17/100,000 in 1999 and a significant change in the proportion of invasive isolates belonging to types 1 and 12F were observed. The serotype coverage rate by the 23-valent polysaccharide vaccine among the elderly was 92.9%, and the serotype coverage rate by the 7-, 9-, and 11-valent pneumococcal conjugate vaccines among children less than 2 years old were 71.7, 75.2, and 81.4%, respectively. Invasive isolates with reduced susceptibility to penicillin or erythromycin increased from 1995 to 1999, with a high proportion of the penicillin-nonsusceptible invasive isolates originating from people 60 years old or older (57.0%). These observations underline the importance of adequate surveillance systems of invasive pneumococcal disease to introduce and maintain national vaccine strategies and adequate antibiotic policy. 相似文献