全文获取类型
收费全文 | 2497篇 |
免费 | 145篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 73篇 |
妇产科学 | 24篇 |
基础医学 | 381篇 |
口腔科学 | 89篇 |
临床医学 | 332篇 |
内科学 | 516篇 |
皮肤病学 | 70篇 |
神经病学 | 295篇 |
特种医学 | 81篇 |
外科学 | 300篇 |
综合类 | 6篇 |
一般理论 | 3篇 |
预防医学 | 219篇 |
眼科学 | 25篇 |
药学 | 121篇 |
中国医学 | 1篇 |
肿瘤学 | 103篇 |
出版年
2023年 | 18篇 |
2022年 | 24篇 |
2021年 | 45篇 |
2020年 | 35篇 |
2019年 | 40篇 |
2018年 | 33篇 |
2017年 | 46篇 |
2016年 | 75篇 |
2015年 | 49篇 |
2014年 | 75篇 |
2013年 | 165篇 |
2012年 | 173篇 |
2011年 | 167篇 |
2010年 | 110篇 |
2009年 | 129篇 |
2008年 | 169篇 |
2007年 | 166篇 |
2006年 | 156篇 |
2005年 | 181篇 |
2004年 | 152篇 |
2003年 | 141篇 |
2002年 | 132篇 |
2001年 | 24篇 |
2000年 | 14篇 |
1999年 | 30篇 |
1998年 | 27篇 |
1997年 | 21篇 |
1996年 | 19篇 |
1995年 | 24篇 |
1994年 | 15篇 |
1993年 | 10篇 |
1992年 | 20篇 |
1991年 | 8篇 |
1990年 | 7篇 |
1988年 | 10篇 |
1987年 | 8篇 |
1986年 | 7篇 |
1985年 | 10篇 |
1984年 | 6篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1981年 | 9篇 |
1979年 | 6篇 |
1978年 | 12篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1972年 | 4篇 |
1970年 | 6篇 |
1966年 | 6篇 |
排序方式: 共有2648条查询结果,搜索用时 51 毫秒
71.
72.
HH Wensink J Dunkel S Heidenreich K Drescher RE Goldstein H Löwen JM Yeomans 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(36):14308-14313
Turbulence is ubiquitous, from oceanic currents to small-scale biological and quantum systems. Self-sustained turbulent motion in microbial suspensions presents an intriguing example of collective dynamical behavior among the simplest forms of life and is important for fluid mixing and molecular transport on the microscale. The mathematical characterization of turbulence phenomena in active nonequilibrium fluids proves even more difficult than for conventional liquids or gases. It is not known which features of turbulent phases in living matter are universal or system-specific or which generalizations of the Navier-Stokes equations are able to describe them adequately. Here, we combine experiments, particle simulations, and continuum theory to identify the statistical properties of self-sustained meso-scale turbulence in active systems. To study how dimensionality and boundary conditions affect collective bacterial dynamics, we measured energy spectra and structure functions in dense Bacillus subtilis suspensions in quasi-2D and 3D geometries. Our experimental results for the bacterial flow statistics agree well with predictions from a minimal model for self-propelled rods, suggesting that at high concentrations the collective motion of the bacteria is dominated by short-range interactions. To provide a basis for future theoretical studies, we propose a minimal continuum model for incompressible bacterial flow. A detailed numerical analysis of the 2D case shows that this theory can reproduce many of the experimentally observed features of self-sustained active turbulence. 相似文献
73.
Knut W Sørgaard Grigory Rezvy Anatoly Bugdanov Tore Sørlie Trond Bratlid 《International journal of mental health systems》2013,7(1):1-8
Background
We compared demography, diagnoses and clinical needs in acutely admitted psychiatric hospital patients in northwest Russia and northern Norway.Method
All acutely admitted psychiatric patients in 1 psychiatric hospital in north-west Russia and 2 in northern Norway were in a three months period assessed with HoNOS and a Norwegian form developed to study acute psychiatric services (MAP). Data from a total of 841 patients were analysed (377 Norwegian, 464 Russian) with univariate and multivariate statistics.Results
Russian patients were more often males who had paid work. 2/3 were diagnosed with alcohol and organic disorders, and 70% reported problems related to sleep. Depression was widespread, as were problems associated with occupation. Many more Norwegian patients were on various forms of social security and lived in community supported homes. They had a clinical profile of affective disorders, use of drugs, suicidality and problems with activities involved of daily life. Slightly more Norwegian patients were involuntary admitted.Conclusion
Acutely admitted psychiatric patients in North West Russia and Northern Norwegian showed different clinical profiles: alcohol, depression and organic disorders characterised Russian patients, affective disorders, suicidality and use of drugs characterised the Norwegians. Whereas Norwegian patients are mainly referred from GPs the Russians come via 1.line psychiatric services (“dispensaries”). Average length of stay for Russian patients was 2.5 times longer than that of the Norwegian. 相似文献74.
Rasmussen LB Mikkelsen K Haugen M Pripp AH Fields JZ Førre ØT 《Clinical rheumatology》2012,31(5):821-827
Treatments offered at the Maharishi Ayurveda Health Centre in Norway are based on Maharishi Vedic Medicine (MVM). MVM is a
consciousness-based revival by Maharishi Mahesh Yogi, the founder of the Transcendental Meditation (TM) program of the ancient
Ayurvedic medicine tradition in India. To extend from 6 to 24 months, a pilot study of the effects of the treatment program
at the Health Centre on fibromyalgia. Retesting 2 years after a clinical trial. In this intention to treat study, 31 women
with a diagnosis of fibromyalgia received an individually tailored program of (1) physiological purification therapy (Maharishi
Panchakarma) and (2) Ayurvedic recommendations regarding daily routine and diet including a novel approach to food intolerance.
Five subjects chose to learn TM for stress reduction, pain management and personal development. All were recommended Ayurvedic
herbal products for follow-up treatment. A modified Fibromyalgia Impact Questionnaire (FIQ) that included seven dimensions.
Scores at 24 months follow-up were compared with pre-treatment scores. At 24-months follow-up, there were significant reductions
(26% to 44%) in six of the seven fibromyalgia dimensions: impairment of working ability, pain, tiredness, morning tiredness,
stiffness and anxiety. The 7th, depression, decreased 32% (borderline significant). At 24 months, the four subjects who continued
practising TM, had almost no symptoms and significantly lower FIQ change scores (−92% to 97%) than the non-meditators on all
outcomes. This pilot study suggests that the treatments and health promotion programs offered at the Maharishi Ayurveda Health
Centre in Norway lead to long-term reductions in symptoms of fibromyalgia, which is considered a treatment-resistant condition,
and further studies are warranted. 相似文献
75.
Duri K Gumbo F Kristiansen K Mapingure M Munjoma M Chirenje M Rusakaniko S Stray-Pedersen B Műller F 《AIDS research and human retroviruses》2012,28(8):885-893
To characterize phylogenetic relatedness of plasma HIV-1 RNA subtype C env gp120 viral variants capable of establishing an infection following heterosexual and subsequent vertical transmission events a 650-base pair fragment within the C2-V5 subregion was sequenced from four HIV-1-infected families each consisting of biological parent(s), index children (first), and subsequent (second) siblings. None of the family members had received antiretroviral therapy at the time of sample collection. Sequence alignment and analysis were done using Gene Doc, Clustal X, and MEGA software programs. Second siblings' sequences were homogeneous and clustered in a single branch while first siblings' sequences were more heterogeneous, clustering in separate branches, suggestive of more than one donor variants responsible for the infection or evolution from founder variant(s) could have occurred. While the directionality for heterosexual transmission could not be determined, homogeneous viral variants were a unique characteristic of maternal variants as opposed to the more heterogeneous paternal variants. Analysis of families' sequences demonstrated a localized expansion of the subtype C infection. We demonstrated that families' sequences clustered quite closely with other regional HIV-1 subtype C sequences supported by a bootstrap value of 86%, confirming the difficulty of classifying subtype C sequences on a geographic basis. Data are indicative of several mechanisms that may be involved in both vertical and heterosexual transmission. Larger studies are warranted to address the caveats of this study and build on the strengths. Our study could be the beginning of family-based HIV-1 intervention research in Zimbabwe. 相似文献
76.
77.
Liang Li Yan Lin Fengling Mi Shouyong Tan Bing Liang Chaojun Guo Lian Shi Li Liu Fang Gong Yuanyuan Li Jingyu Chi Rony Zachariah Anil Kapur Knut Lönnroth Anthony D. Harries 《Tropical medicine & international health : TM & IH》2012,17(10):1294-1301
Objective There is a high burden of both diabetes (DM) and tuberculosis (TB) in China, and this study aimed to assess feasibility and results of screening patients with TB for DM within the routine healthcare setting of six health facilities. Method Agreement on how to screen, monitor and record was reached in May 2011 at a stakeholders’ meeting, and training was carried out for staff in the six facilities in July 2011. Implementation started in September 2011, and we report on 7 months of activities up to 31 March 2012. Results There were 8886 registered patients with TB. They were first asked whether they had DM. If the answer was no, they were screened with a random blood glucose (RBG) followed by fasting blood glucose (FBG) in those with RBG ≥ 6.1 mm (one facility) or with an initial FBG (five facilities). Those with FBG ≥ 7.0 mm were referred to DM clinics for diagnostic confirmation with a second FBG. Altogether, 1090 (12.4%) patients with DM were identified, of whom 863 (9.7%) had a known diagnosis of DM. Of 8023 patients who needed screening for DM, 7947 (99%) were screened. This resulted in a new diagnosis of DM in 227 patients (2.9% of screened patients), and of these, 226 were enrolled to DM care. In addition, 575 (7.8%) persons had impaired fasting glucose (FBG 6.1 to <7.0 mm ). Prevalence of DM was significantly higher in patients in health facilities serving urban populations (14.0%) than rural populations (10.6%) and higher in hospital patients (13.5%) than those attending TB clinics (8.5%). Conclusion This pilot project shows that it is feasible to screen patients with TB for DM in the routine setting, resulting in a high yield of patients with known and newly diagnosed disease. Free blood tests for glucose measurement and integration of TB and DM services may improve the diagnosis and management of dually affected patients. 相似文献
78.
TB Wyller LO Watne A Torbergsen K Engedal F Frihagen V Juliebø I Saltvedt E Skovlund J Ræder S Conroy 《BMC geriatrics》2012,12(1):36
ABSTRACT: BACKGROUND: Hip fracture mainly affect older people. It is associated with high morbidity and mortality, and in particular a high frequency of delirium. Incident delirium following hip fracture is associated with an increased risk of dementia in the following months, but it is still not firmly established whether this is an association or a causal relationship. Orthogeriatric units vary with respect to content and timing of the intervention. One main effect of orthogeriatric care may be the prevention of delirium, especially if preoperative and postoperative care are provided. Thus, the aim of Oslo Orthogeriatric Trial, is to assess whether combined preoperative and postoperative orthogeriatric care can reduce the incidence of delirium and improve cognition following hip fracture. Methods/design: Inclusion and randomisation will take place in the Emergency Department, as soon as possible after admission. All patients with proximal femur fractures are eligible, irrespective of age, pre-fracture function and accommodation, except if the fracture is caused by a high energy trauma or the patient is terminally ill. The intervention is pre-and post-operative orthogeriatric care delivered on a dedicated acute geriatric ward. The primary outcome measure is a composite endpoint combining the Clinical Dementia Rating Scale (CDR) and the 10 word memory task at four months after surgery. Secondary outcomes comprise incident delirium, length of stay, cognition, mobility, place of residence, activities of daily living and mortality, measured at 4 and 12 months after surgery. We have included 332 patients in the period 17th September 2009 to 5th January 2012. DISCUSSION: Our choice of outcome measures and our emphasis of orthogeriatric care in the preoperative as well as the postoperative phase will enable us to provide new knowledge on the impact of orthogeriatric care on cognition. Trials registration: ClinicalTrials.gov NCT01009268. 相似文献
79.
80.
Ana Gvozdenovic Matthias JE Arlt Carmen Campanile Patrick Brennecke Knut Husmann Yufei Li Walter Born Roman Muff Bruno Fuchs 《Journal of bone and mineral research》2013,28(4):838-847
Formation of metastases in the lungs is the major cause of death in patients suffering from osteosarcoma (OS). Metastases at presentation and poor response to preoperative chemotherapy are strong predictors for poor patient outcome. The elucidation of molecular markers that promote metastasis formation and/or chemoresistance is therefore of importance. CD44 is a plasma membrane glycoprotein that binds to the extracellular matrix component hyaluronan (HA) and has been shown to be involved in metastasis formation in a variety of other tumors. Here we investigated the role of CD44 expression on OS tumor formation and metastasis. High CD44 expression, evaluated with a tissue microarray including samples from 53 OS patients and stained with a pan‐CD44 antibody (Hermes3), showed a tendency (p < 0.08) to shortened overall survival. However, nonresponders and patients with lung metastases and high CD44 expression had significantly poorer prognosis than patients with low CD44 expression. Overexpression of the standard CD44 isoform (CD44s) and its HA‐binding defective mutant R41A in osteoblastic SaOS‐2 cells resulted in HA‐independent higher migration rates and increased chemoresistance, partially dependent on HA. In an orthotopic mouse model of OS, overexpression of CD44s in SaOS‐2 cells resulted in an HA‐dependent increased primary tumor formation and increased numbers of micrometastases and macrometastases in the lungs. In conclusion, although CD44 failed to be an independent predictor for patient outcome in this limited cohort of OS patients, increased CD44 expression was associated with even worse survival in patients with chemoresistance and with lung metastases. CD44‐associated chemoresistance was also observed in vitro, and increased formation of lung metastases was found in vivo in SCID mice. © 2013 American Society for Bone and Mineral Research. 相似文献