全文获取类型
收费全文 | 2052篇 |
免费 | 109篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 137篇 |
妇产科学 | 70篇 |
基础医学 | 222篇 |
口腔科学 | 35篇 |
临床医学 | 174篇 |
内科学 | 329篇 |
皮肤病学 | 107篇 |
神经病学 | 260篇 |
特种医学 | 36篇 |
外科学 | 150篇 |
综合类 | 56篇 |
一般理论 | 6篇 |
预防医学 | 128篇 |
眼科学 | 60篇 |
药学 | 177篇 |
1篇 | |
中国医学 | 4篇 |
肿瘤学 | 211篇 |
出版年
2023年 | 20篇 |
2022年 | 42篇 |
2021年 | 88篇 |
2020年 | 62篇 |
2019年 | 57篇 |
2018年 | 66篇 |
2017年 | 54篇 |
2016年 | 76篇 |
2015年 | 66篇 |
2014年 | 85篇 |
2013年 | 113篇 |
2012年 | 214篇 |
2011年 | 213篇 |
2010年 | 84篇 |
2009年 | 82篇 |
2008年 | 126篇 |
2007年 | 135篇 |
2006年 | 114篇 |
2005年 | 116篇 |
2004年 | 95篇 |
2003年 | 77篇 |
2002年 | 64篇 |
2001年 | 7篇 |
2000年 | 5篇 |
1999年 | 6篇 |
1998年 | 12篇 |
1997年 | 16篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1971年 | 3篇 |
1970年 | 5篇 |
1969年 | 3篇 |
1968年 | 2篇 |
1967年 | 2篇 |
排序方式: 共有2168条查询结果,搜索用时 531 毫秒
91.
92.
93.
Maro Ohanian Philippe Telouk Steven Kornblau Francis Albarede Peter Ruvolo Rebecca S. S. Tidwell Adriana Plesa Rashmi Kanagal-Shamanna Eva-Laure Matera Jorge Cortes Arch Carson Charles Dumontet 《American journal of hematology》2020,95(4):422-434
Despite abundant epidemiological data linking metals to leukemia and other cancers, baseline values of toxic and essential metals in patients with leukemia and the clinical impact of these metals remain unknown. Thus, we sought to quantify metal values in untreated patients with acute myeloid leukemia (AML) and controls and determine the impact of metal values on AML patients' survival. Serum samples from patients with untreated AML and controls at Hospices Civils de Lyon were analyzed and compared for trace metals and copper isotopic abundance ratios with inductively coupled plasma mass spectrometry. Survival analysis was performed as a function of metal values, and a multi-metal score was developed for patients with AML. Serum samples were collected from 67 patients with untreated AML and 94 controls. Most patients had intermediate-risk cytogenetics (63.1%) without FLT3 internal tandem duplication mutations (75.6%) or NPM1 mutations (68.1%). Most metal values differed significantly between AML and control groups. Patients with lower magnesium and higher cadmium values had the worst survival rates, with only 36% surviving at 6 months (P = .001). The adverse prognostic effect of this combination was maintained on multivariate analysis. Based on this, we developed a novel metal score, which accounts for multiple relative abnormalities in the values of five toxic and five essential metals. Patients with a higher metal score had significantly worse survival, which was maintained on multivariate analysis (P = .03). This baseline metal scoring system was also prognostic when we applied it to a separate population of front-line AML patients. 相似文献
94.
Diabetes mellitus is a combined metabolic disorder which includes hyperglycemia,dyslipidemia,stroke and several other complications.Various groups all over the world are relentlessly working out the possible role of a vast number of genes associated with type 2 diabetes(T2DM).Inflammation is an important outcome of any kind of imbalance in the body and is therefore an indicator of several diseases,including T2DM.Various ethnic populations around the world show different levels of variations in single nucleotide polymorphisms(SNPs).The present review was undertaken to explore the association of cytokine gene polymorphisms with T2DM in populations of different ethnicities.This will lead to the understanding of the role of cytokine genes in T2DM risk and development.Association studies of genotypes of SNPs present in cytokine genes will help to identify risk haplotype(s)for disease susceptibility by developing prognostic markers and alter treatment strategies for T2DM and related complications.This will enable individuals at risk to take prior precautionary measures and avoid or delay the onset of the disease.Future challenges will be to understand the genotypic interactions between SNPs in one cytokine gene or several genes at different loci and study their association with T2DM. 相似文献
95.
Immunotherapeutic vaccines to drugs of abuse, including nicotine, cocaine, heroin, oxycodone, methamphetamine, and others are being developed. The theoretical basis of such vaccines is to induce antibodies that sequester the drug in the blood in the form of antibody-bound drug that cannot cross the blood brain barrier, thereby preventing psychoactive effects. Because the drugs are haptens a successful vaccine relies on development of appropriate hapten-protein carrier conjugates. However, because induction of high and prolonged levels of antibodies is required for an effective vaccine, and because injection of T-independent haptenic drugs of abuse does not induce memory recall responses, the role of adjuvants during immunization plays a critical role. As reviewed herein, preclinical studies often use strong adjuvants such as complete and incomplete Freund's adjuvant and others that cannot be, or in the case of many newer adjuvants, have never been, employed in humans. Balanced against this, the only adjuvant that has been included in candidate vaccines in human clinical trials to nicotine and cocaine has been aluminum hydroxide gel. While aluminum salts have been widely utilized worldwide in numerous licensed vaccines, the experience with human responses to aluminum salt-adjuvanted vaccines to haptenic drugs of abuse has suggested that the immune responses are too weak to allow development of a successful vaccine. What is needed is an adjuvant or combination of adjuvants that are safe, potent, widely available, easily manufactured, and cost-effective. Based on our review of the field we recommend the following adjuvant combinations either for research or for product development for human use: aluminum salt with adsorbed monophosphoryl lipid A (MPLA); liposomes containing MPLA [L(MPLA)]; L(MPLA) adsorbed to aluminum salt; oil-in-water emulsion; or oil-in-water emulsion containing MPLA. 相似文献
96.
Ezra E. Smith Craig E. Tenke Patricia J. Deldin Madhukar H. Trivedi Myrna M. Weissman Randy P. Auerbach Gerard E. Bruder Diego A. Pizzagalli Jürgen Kayser 《Psychophysiology》2020,57(2):e13483
Prior research has identified two resting EEG biomarkers with potential for predicting functional outcomes in depression: theta current density in frontal brain regions (especially rostral anterior cingulate cortex) and alpha power over posterior scalp regions. As little is known about the discriminant and convergent validity of these putative biomarkers, a thorough evaluation of these psychometric properties was conducted toward the goal of improving clinical utility of these markers. Resting 71-channel EEG recorded from 35 healthy adults at two sessions (1-week retest) were used to systematically compare different quantification techniques for theta and alpha sources at scalp (surface Laplacian or current source density [CSD]) and brain (distributed inverse; exact low resolution electromagnetic tomography [eLORETA]) level. Signal quality was evaluated with signal-to-noise ratio, participant-level spectra, and frequency PCA covariance decomposition. Convergent and discriminant validity were assessed within a multitrait-multimethod framework. Posterior alpha was reliably identified as two spectral components, each with unique spatial patterns and condition effects (eyes open/closed), high signal quality, and good convergent and discriminant validity. In contrast, frontal theta was characterized by one low-variance component, low signal quality, lack of a distinct spectral peak, and mixed validity. Correlations between candidate biomarkers suggest that posterior alpha components constitute reliable, convergent, and discriminant biometrics in healthy adults. Component-based identification of spectral activity (CSD/eLORETA-fPCA) was superior to fixed, a priori frequency bands. Improved quantification and conceptualization of frontal theta is necessary to determine clinical utility. 相似文献
97.
Madhukar B. Kolli Nandini D.P.K. Manne Radhakrishna Para Siva K. Nalabotu Geeta Nandyala Tolou Shokuhfar Kun He Azhang Hamlekhan Jane Y. Ma Paulette S. Wehner Lucy Dornon Ravikumar Arvapalli Kevin M. Rice Eric R. Blough 《Biomaterials》2014
Cerium oxide (CeO2) nanoparticles have been posited to exhibit potent anti-oxidant activity which may allow for the use of these materials in biomedical applications. Herein, we investigate whether CeO2 nanoparticle administration can diminish right ventricular (RV) hypertrophy following four weeks of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). Male Sprague Dawley rats were randomly divided into three groups: control, MCT only (60 mg/kg), or MCT + CeO2 nanoparticle treatment (60 mg/kg; 0.1 mg/kg). Compared to the control group, the RV weight to body weight ratio was 45% and 22% higher in the MCT and MCT + CeO2 groups, respectively (p < 0.05). Doppler echocardiography demonstrated that CeO2 nanoparticle treatment attenuated monocrotaline-induced changes in pulmonary flow and RV wall thickness. Paralleling these changes in cardiac function, CeO2 nanoparticle treatment also diminished MCT-induced increases in right ventricular (RV) cardiomyocyte cross sectional area, β-myosin heavy chain, fibronectin expression, protein nitrosylation, protein carbonylation and cardiac superoxide levels. These changes with treatment were accompanied by a decrease in the ratio of Bax/Bcl2, diminished caspase-3 activation and reduction in serum inflammatory markers. Taken together, these data suggest that CeO2 nanoparticle administration may attenuate the hypertrophic response of the heart following PAH. 相似文献
98.
Venkanna Balaganur Nitya Nand Pathak Madhu C. Lingaraju Amar Sunil More Najeeb Latief Rashmi Rekha Kumari 《Connective tissue research》2014,55(5-6):367-377
The aim of the present study was to evaluate in vivo modulatory effect of S-methylisothiourea (SMT), a preferential inhibitor of inducible nitric oxide synthase (iNOS) on pain and pathology in the surgical model of osteoarthritis (OA) in rats. The OA was produced by the anterior cruciate ligament transection (ACLT) and medial meniscectomy (MMx) of right knee. SMT was administered 1 day prior to the production of OA and continued up to day 42 postoperation. Mechanical hyperalgesia, thermal hyperalgesia, tail flick latency after repeated flexion and extension of OA knee and knee diameter of right knee were determined at weekly intervals. Serum levels of IL-1β, TNF-α and nitrite concentration were determined at the end of the experiment. Glycosaminoglycan (GAG) content, collagen content and histopathological evaluation of articular cartilage were also determined at the end of the experiment. SMT reduced mechanical hyperalgesia and the serum levels of IL-1β, TNF-α and nitrite. Further, SMT reduced the loss of GAG from articular cartilage. Microscopically, SMT reduced the severity of the cartilage lesion. The results indicate the effectiveness of SMT in attenuating the pain and pathology of experimental OA phase by reducing the production of nitric oxide and interleukin-1β and tumor necrosis factor-α, which are known to play a major role in the pathophysiology of OA. 相似文献
99.
The opportunity to undergo an induced pluripotent stem cell-based autologous transplant can strike patients as a chance for a cure from a debilitating condition with few options for respite. However, when clinical studies of this caliber present themselves, patients and researchers, each with their own set of motives, may find it difficult to take a balanced approach to evaluating them. We present a patient-centered risk-benefit analysis of the iPSC-based clinical research currently underway in Japan, including a survey of in vitro and in vivo tests that support this project, an in-depth discussion of risks, and further elucidation of considerations patients may wish to consider. The arguments presented will assist patients in undertaking a more informed decision-making process. 相似文献
100.
Jose Ramon Fernandez-Alvarez Rashmi Shreyans Gandhi Philip Amess Liam Mahoney Ryan Watkins Heike Rabe 《European journal of pediatrics》2014,173(1):93-98
Despite the paucity of evidence, the practice of weaning nasal continuous positive airway pressure (NCPAP) is widespread. However, the most clinically effective non-invasive ventilatory support strategy remains to be determined. We compared the outcome of very premature infants with respiratory distress syndrome treated with a combination of NCPAP and heated humidified high-flow nasal cannula (HHFNC) versus NCPAP and low-flow nasal cannula (LFNC). Between 2004 and 2008, patients ≤28 weeks of gestation and <1,250 g of birth weight were treated with NCPAP + HHFNC or NCPAP + LFNC. Their respiratory and non-respiratory outcome including cost-effectiveness was compared after matching for antenatal steroid doses, mode of delivery, birth plurality, gestational age, birth weight, gender, surfactant doses, length of mechanical ventilation and clinical risk index for babies-II (CRIB-II) score. Thirty-nine infants received HHFNC + NCPAP, and 40 received NCPAP + LFNC. Median gestational age and birth weight were 27 weeks and 930 g and 27 weeks and 980 g, respectively. The total number of NCPAP days was significantly reduced by 50 % in the HHFNC group. Thirteen percent of the patients on NCPAP suffered from nasal bridge lesions compared to none on HHFNC. Respiratory and non-respiratory outcome was not significantly different otherwise. Combination of NCPAP and HHFNC reduced costs by 33 %. Conclusions: HHFNC shortens NCPAP time without increasing overall length of non-invasive respiratory support in very preterm infants. Unlike NCPAP, HHFNC does not seem to increase the risk of nasal trauma and appears to improve cost-effectiveness whilst producing otherwise equal respiratory and non-respiratory outcomes. 相似文献