全文获取类型
收费全文 | 3936篇 |
免费 | 274篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 146篇 |
妇产科学 | 86篇 |
基础医学 | 700篇 |
口腔科学 | 16篇 |
临床医学 | 386篇 |
内科学 | 877篇 |
皮肤病学 | 96篇 |
神经病学 | 427篇 |
特种医学 | 73篇 |
外科学 | 387篇 |
综合类 | 25篇 |
一般理论 | 1篇 |
预防医学 | 321篇 |
眼科学 | 75篇 |
药学 | 252篇 |
中国医学 | 3篇 |
肿瘤学 | 351篇 |
出版年
2023年 | 27篇 |
2022年 | 42篇 |
2021年 | 96篇 |
2020年 | 64篇 |
2019年 | 104篇 |
2018年 | 95篇 |
2017年 | 63篇 |
2016年 | 81篇 |
2015年 | 109篇 |
2014年 | 133篇 |
2013年 | 200篇 |
2012年 | 320篇 |
2011年 | 333篇 |
2010年 | 172篇 |
2009年 | 155篇 |
2008年 | 257篇 |
2007年 | 277篇 |
2006年 | 268篇 |
2005年 | 261篇 |
2004年 | 261篇 |
2003年 | 273篇 |
2002年 | 207篇 |
2001年 | 40篇 |
2000年 | 22篇 |
1999年 | 42篇 |
1998年 | 45篇 |
1997年 | 39篇 |
1996年 | 31篇 |
1995年 | 34篇 |
1994年 | 19篇 |
1993年 | 19篇 |
1992年 | 12篇 |
1991年 | 19篇 |
1990年 | 10篇 |
1989年 | 10篇 |
1988年 | 8篇 |
1987年 | 8篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1982年 | 8篇 |
1979年 | 10篇 |
1977年 | 3篇 |
1975年 | 2篇 |
1974年 | 6篇 |
1972年 | 7篇 |
1971年 | 2篇 |
1970年 | 3篇 |
1969年 | 2篇 |
1968年 | 4篇 |
排序方式: 共有4228条查询结果,搜索用时 15 毫秒
41.
Rodolphe Thiébaut Jérémie Guedj Hélène Jacqmin-Gadda Geneviève Chêne Pascale Trimoulet Didier Neau Daniel Commenges 《BMC medical research methodology》2006,6(1):38-9
Background
Mathematical models are widely used for studying the dynamic of infectious agents such as hepatitis C virus (HCV). Most often, model parameters are estimated using standard least-square procedures for each individual. Hierarchical models have been proposed in such applications. However, another issue is the left-censoring (undetectable values) of plasma viral load due to the lack of sensitivity of assays used for quantification. A method is proposed to take into account left-censored values for estimating parameters of non linear mixed models and its impact is demonstrated through a simulation study and an actual clinical trial of anti-HCV drugs. 相似文献42.
Mitral cell temporal response patterns evoked by odor mixtures in the rat olfactory bulb 总被引:3,自引:0,他引:3
Mammals generally have the ability to extract odor information contained in complex mixtures of molecular components. However, odor mixture processing has been studied electrophysiologically only in insects, crustaceans, and fish. As a first step toward a better understanding of this processing in high vertebrates, we studied the representation of odor mixtures in the rat olfactory bulb, i.e., the second-order level of the olfactory pathways. We compared the single-unit responses of mitral cells, the main cells of the olfactory bulb, to pure odors and to their binary mixtures. Eighty-six mitral cells were recorded in anesthetized freely breathing rats stimulated with five odorants and their 10 binary mixtures. The spontaneous activity and the odor-evoked responses were characterized by their temporal distribution of activity along the respiratory cycle, i.e., by cycle-triggered histograms. Ninety percent of the mixtures were found to evoke a response when at least one of their two components evoked a response. Mixture-evoked patterns were analyzed to describe the modalities of the combination of patterns evoked by the two components. In most of the cases, the mixture pattern was closely similar to one of the component patterns. This dominance of a component over the other one was related to the responsiveness of the cell to the individual components of the mixture, to the molecular nature of the stimulus, and to the coarse shape of individual response patterns. This suggests that the components of binary mixtures may be encoded simultaneously by different odor-specific temporal distributions of activity. 相似文献
43.
44.
Franois-Xavier Briand Eric Niqueux Audrey Schmitz Claire Martenot Martine Cherbonnel Pascale Massin Florian Kerbrat Marina Chatel Carole Guillemoto Cecile Guillou-Cloarec Katell Ogor Aurlie Le Prioux Chantal Alle Vronique Beven Edouard Hirchaud Yannick Blanchard Axelle Scoizec Sophie Le Bouquin Nicolas Eterradossi Batrice Grasland 《Emerging infectious diseases》2021,27(2):508
We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds. 相似文献
45.
Natacha Martin Anne Bergougnoux Nesrine Baatallah Benoit Chevalier Jessica Varilh David Baux Bruno Costes Pascale Fanen Caroline Raynal Isabelle Sermet-Gaudelus Emmanuelle Girodon Magali Taulan-Cadars Alexandre Hinzpeter 《Journal of cystic fibrosis》2021,20(3):464-472
BackgroundMinigenes and in silico prediction tools are commonly used to assess the impact on splicing of CFTR variants. Exon skipping is often neglected though it could impact the efficacy of targeted therapies. The aim of the study was to identify exon skipping associated with CFTR variants and to evaluate in silico predictions of seven freely available software.MethodsCFTR basal exon skipping was evaluated on endogenous mRNA extracted from non-CF nasal cells and on two CFTR minigene banks. In silico tools and minigene systems were used to evaluate the impact of CFTR exonic variants on exon skipping.ResultsData showed that out of 65 CFTR variants tested, 26 enhanced exon skipping and that in silico prediction efficacy was of 50%-66%. Some in silico tools presented predictions with a bias towards the occurrence of splicing events while others presented a bias towards the absence of splicing events (non-detection including true negatives and false negatives). Classification of exons depending on their basal exon skipping level increased prediction rates up to 80%.ConclusionThis study indicates that taking basal exon skipping into account could orientate the choice of the in silico tools to improve prediction rates. It also highlights the need to validate effects using in vitro assays or mRNA studies in patients. Eventually, it shows that variant-guided therapy should also target exon skipping associated with variants. 相似文献
46.
Mouillet Guillaume Falcoz Antoine Fritzsch Joëlle Almotlak Hamadi Jacoulet Pascale Pivot Xavier Villanueva Cristian Mansi Laura Kim Stefano Curtit Elsa Meneveau Nathalie Adotevi Olivier Jary Marine Eberst Guillaume Vienot Angelique Calcagno Fabien Pozet Astrid Djoumakh Oumelkheir Borg Christophe Westeel Virginie Anota Amélie Paget-Bailly Sophie 《Quality of life research》2021,30(11):3255-3266
Quality of Life Research - Routine Electronic Monitoring of Health-Related Quality of Life (HRQoL) (REMOQOL) in clinical care with real-time feedback to physicians could help to enhance... 相似文献
47.
Jean-Christophe Zech Laurette Morlé Pascale Vincent Nicole Alloisio Muriel Bozon Colette Gonnet Solange Milazzo Jean-Daniel Grange Christiane Trepsat Jacqueline Godet Henri Plauchu 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1999,237(5):387-393
· Background: It has been previously described that Wagner disease is linked to chromosome 5q13-q14. This study was carried
out to describe the ophthalmological aspects and report the results of genetic linkage analysis in a large pedigree affected
by Wagner disease. · Methods: Fourty members of one same family agreed to be examined. · Results: Twenty patients presented
vitreoretinal degeneration in both eyes without any extra-ocular abnormalities. In young patients, visual acuity was usually
normal after correction of frequent mild myopia. Presenile cataracts progressed by the third decade and required removal for
visual rehabilitation. The primary disorder involved an abnormal vitreous. A few avascular vitreous bands were usually the
only optical feature in the mostly empty vitreous cavity. A circumferential vitreous condensation formed in contact with the
retina on many spots. Less common retinal findings included retinal detachment, abnormal retinal pigmentation, progressive
atrophy of the RPE simulating choroideremia and lattice degeneration. Genetic analysis revealed a highly significant linkage
(lod score >5.0) between the disease and 10 markers of the chromosome 5q13-q14 region. Two recombination events allowed us
to refine the linked interval to 20 cM between the D5S650 and D5S618 markers. · Conclusion: Ophthalmological aspects of Wagner’s
disease appear to progress with age. Regular ophthalmological examination is important for detecting retinal abnormalities.
The gene involved in Wagner’s disease lies in a 20 cM interval on chromosome 5q13-q14.
Received: 30 June 1998 Revised version received: 5 October 1998 Accepted: 6 October 1998 相似文献
48.
49.
Bernard Tetu Yves Fradet Pierre Allard Chantal Veilleux Nancy Roberge Pascale Bernard 《The Journal of urology》1996,155(5):1784-1788
Purpose
The usefulness of the expression of HER2/neu oncoprotein and of p53 and Rb suppressor gene product as predictors of tumor recurrence was evaluated by using a bank of prospectively collected primary papillary bladder tumors treated initially only by transurethral resection.Materials and Methods
The expression of HER-2/neu oncoprotein and of p53 and Rb suppressor genes was evaluated by immunohistochemistry in 256, 265 and 74 specimens of primary Ta/T1 superficial bladder tumors obtained from patients enrolled in a prospective study from 1990 to 1992. Survival analysis was used to evaluate the association between time to first recurrence and expression of each marker, the follow-up period extending to March 1994. Immunostaining for p53 and HER-2/neu was performed on paraffin-embedded tissue and, for Rb, on frozen tissue only.Results
Her-2/neu was expressed in 21 (8.2 percent) cases and p53 in 39 cases (14.7 percent); Rb expression was altered in 12 (16.2 percent). In this study, p53 expression was only related to earlier recurrence in a univariate analysis. Multivariate analysis, however, failed to recognize p53 expression as an independent predictor of recurrence.Conclusions
Our study demonstrate the low prevalence of HER2/neu, p53 and altered Rb expression in superficial TCC at initial resection. Only p53 expression was significantly associated with an earlier first tumor recurrence, but this association was not independent of other prognostic factors. 相似文献50.
R M Pascale M M Simile G Satta M A Seddaiu L Daino G Pinna M A Vinci L Gaspa F Feo 《Anticancer research》1991,11(4):1617-1624
Male Wistar rats, initiated with diethylnitrosamine (DENA), were subjected to a selection treatment, according to the "resistant hepatocyte" model, followed or not followed by phenobarbital (PB). Rats received, for 3 weeks after selection, 4 i.m. doses (96 mmol/kg) of L-methionine, S-adenosyl-L-methionine (SAM), or 5'-methylthioadenosine (MTA), a SAM catabolite formed during polyamine synthesis or by spontaneous splitting of SAM at physiologic temperature and pH. They were then killed. In some rats, SAM and MTA treatments were started 20 weeks after initiation. The animals were killed 3 weeks later and persistent (neoplastic) nodules (PN) were collected. Some rat groups received 1/2 and 1/4 of the above SAM and MTA doses, or 1/8 of the above MTA dose. SAM and MTA, but not methionine, caused a dose-dependent decrease in number and surface area of gamma-glutamyltranspeptidase (GGT)-positive foci, and in labeling index (LI) of focal cells, coupled with remodeling. SAM and MTA liver contents, SAM/S-adenosylhomocysteine (SAH) ratio and overall methylation of liver DNA were low during the development of GGT-positive foci. SAM, but not methionine, caused a dose-dependent recovery of SAM content and DNA methylation, and a partial reconstitution of liver MTA pool. Exogenous MTA only induced the reconstitution of MTA pool, without affecting SAM level and DNA methylation. Recovery of SAM and MTA pool and DNA methylation was found in the rats subjected to SAM plus MTA, indicating the absence of inhibition of DNA methyltransferases in vivo by MTA. MTA also inhibited liver reparative growth in partially hepatectomized rats, without modifying SAM content and DNA methylation of regenerating liver (RL). A high activity of ornithine decarboxylase (ODC) was found in the liver, during the development of preneoplastic foci, and in PN. This activity was inhibited by SAM and MTA treatments. Although MTA was more effective than SAM, the decrease in ODC activity was coupled with a larger fall in DNA synthesis in SAM-treated than in MTA-treated rats. Thus the antipromotion effect of SAM could not merely depend on its (spontaneous) transformation into MTA. Although MTA production may play a role in the SAM antipromotion effect, other mechanisms could be involved. A role of DNA methylation in the inhibition of growth by SAM is suggested. MTA is a potential chemopreventive agent for liver carcinogenesis. 相似文献