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61.
Matthias J. N. Junk Wen Li A. Dieter Schlüter Gerhard Wegner Hans W. Spiess Afang Zhang Dariush Hinderberger 《Macromolecular chemistry and physics.》2011,212(12):1229-1235
The nanoscopic structure of thermoresponsive dendronized polymers below the critical aggregation temperature (TC) is revealed by CW EPR spectroscopy. At temperatures far below TC, the water‐swollen polymers start to dehydrate and hydrophobic cavities are formed. Two different dehydration processes can be discerned, the more effective of which is observed within 4 K below TC. The dehydration predominantly takes place at the peripheral dendritic shell, rendering it increasingly hydrophobic and eventually triggering an interchain aggregation and the formation of mesoglobules at the critical temperature. While the polymer aggregation is mainly dependent on the dendron periphery, the efficiency of the dehydration below TC is closely related to the hydrophobicity of the dendritic core.
62.
Kallala R Graham SM Nikkhah D Kyrkos M Heliotis M Mantalaris A Tsiridis E 《Expert opinion on drug safety》2012,11(1):15-32
INTRODUCTION: Recent evidence suggests that antibiotics exert direct effects on bone at a cellular level, disrupting mitochondrial function and cell activity. This comprehensive literature review aims to evaluate evidence for the effects of antibiotics and antimicrobials on bone and discuss the clinical implications. AREAS COVERED: A literature search was conducted on electronic databases covering a period from 1969 to 2010. Studies were included if they reported in vivo and in vitro experimental findings regarding the use of antibiotics and synthetic antibacterials in both animals and humans, focusing on bone cell function and especially fracture repair. EXPERT OPINION: Current research suggests that these negative results could be due to direct effects of antibiotics on mitochondrial physiology within mammalian cells. Treatment doses of antibiotics, especially those released from topical delivery systems such as bone cements, result in antibiotic concentrations thousands of times higher than those required to inhibit bacterial growth. Our findings suggest a need to develop current antibiotic delivery systems to elute sufficient doses to inhibit bacterial growth without negative effects on bone physiology and fracture repair processes. 相似文献
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Calder PC Dangour AD Diekman C Eilander A Koletzko B Meijer GW Mozaffarian D Niinikoski H Osendarp SJ Pietinen P Schuit J Uauy R 《European journal of clinical nutrition》2010,64(Z4):S1-13
The 9th Unilever Nutrition Symposium entitled 'Essential fats for future health', held on 26-27 May 2010, aimed to review the dietary recommendations for essential fatty acids (EFA); discuss the scientific evidence for the roles of EFA in cognition, immune function and cardiovascular health; and to identify opportunities for joint efforts by industry, academia, governmental and non-governmental organizations to effectively improve health behaviour. This paper summarizes the main conclusions of the presentations given at the symposium. Linoleic acid (LA) and α-linolenic acid (ALA) are EFA that cannot by synthesized by the human body. Docosahexaenoic acid (DHA) is considered as conditionally essential because of its limited formation from ALA in the human body and its critical role in early normal retinal and brain development and, jointly with eicosapentaenoic acid (EPA), in prevention of cardiovascular disease (CVD). Some evidence for possible beneficial roles of n-3 fatty acids for immune function and adult cognitive function is emerging. A higher consumption of polyunsaturated fatty acids (PUFA; >10%E), including LA, ALA and at least 250-500 mg per day of EPA+DHA, is recommended for prevention of coronary heart disease (CHD). Two dietary interventions suggest that EFA may affect CVD risk factors in children similarly as in adults. To ensure an adequate EFA intake of the population, including children, public health authorities should develop clear messages based on current science; ensure availability of healthy, palatable foods; and collaborate with scientists, the food industry, schools, hospitals, health-care providers and communities to encourage consumers to make healthy choices. 相似文献
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Ramin Heshmat Mostafa Qorbani Nafiseh Mozaffarian Shirin Djalalinia Ali Sheidaei Mohammad Esmaeil Motlagh Saeid Safiri Kimia Gohari Asal Ataie-Jafari Gelayol Ardalan Hamid Asayesh Morteza Mansourian Roya Kelishadi 《World journal of pediatrics : WJP》2018,14(1):66-76
Background
This study aimed to assess the socioeconomic inequality and determinants of screen time (ST) frequency in Iranian children and adolescents.Methods
This nationwide study was conducted as part of a national school-based surveillance program among 36,486 students consisting of 50.79% boys and 74.23% urban inhabitants, aged 6–18 years, living in urban and rural areas of 30 provinces of Iran. Socioeconomic inequality in ST, including the time spent for ST, watching TV and leisure-time working with computer, was assessed across quintiles of SES using concentration index (C) and slope index of inequality (SII).Results
Overall, 36,486 students completed the study (response rate 91.25%). Their mean (SD) age was 12.14 (3.36) years. The national estimation of frequency of ST was 31.66% (95% CI 31.16–32.17) with ascending change from 20.80% (95% CI 19.81–21.82) to 36.66% (95% CI 35.47–37.87) from the first to the last quintal of SES. Estimated C value at national level was positive (0.08), which indicate inequality was in favor of low SES groups. Considering the SII values, at national level [? 0.16 (? 0.39, 0.06)], the absolute difference in ST frequency between the bottom and top of the socioeconomic groups had descending trends. In multivariate logistic regression model, family history of obesity, generalized obesity and age were the main significant determinants of prolonged ST, watching TV, and computer working (P < 0.001).Conclusions
Socioeconomic inequality in ST frequency was in favor of low SES groups. These findings are useful for health policies, better programming and future complementary analyses.67.
Priority interventions to improve maternal and child diets in Sub‐Saharan Africa and South Asia 下载免费PDF全文
William A. Masters Katherine Rosettie Sarah Kranz Sarah H. Pedersen Patrick Webb Goodarz Danaei Dariush Mozaffarian 《Maternal & child nutrition》2018,14(2)
Nutrition‐sensitive interventions to improve overall diet quality are increasingly needed to improve maternal and child health. This study demonstrates feasibility of a structured process to leverage local expertise in formulating programmes tailored for current circumstances in South Asia and Africa. We assembled 41 stakeholders in 2 regional workshops and followed a prespecified protocol to elicit programme designs listing the human and other resources required, the intervention's mechanism for impact on diets, target foods and nutrients, target populations, and contact information for partners needed to implement the desired programme. Via this protocol, participants described 48 distinct interventions, which we then compared against international recommendations and global goals. Local stakeholders' priorities focused on postharvest food systems to improve access to nutrient‐dense products (75% of the 48 programmes) and on production of animal sourced foods (58%), as well as education and social marketing (23%) and direct transfers to meet food needs (12.5%). Each programme included an average of 3.2 distinct elements aligned with those recommended by United Nations system agencies in the Framework for Action produced by the Second International Conference on Nutrition in 2014 and the Compendium of Actions for Nutrition developed for the Renewed Efforts Against Child Hunger initiative in 2016. Our results demonstrate that a participatory process can help local experts identify their own priorities for future investments, as a first step in a novel process of rigorous, transparent, and independent priority setting to improve diets among those at greatest risk of undernutrition. 相似文献
68.
Mojgan Tabatabaee Dariush Tayyebi 《The journal of maternal-fetal & neonatal medicine》2013,26(6):517-521
Background. Cytomegalovirus (CMV) is a common opportunistic infection among HIV-infected individuals, a major source of serious complications among organ-transplant recipients, and a leading cause of hearing loss, vision loss, and mental retardation among congenitally infected children. Women infected for the first time during pregnancy are especially likely to transmit CMV to their fetuses.Objective. In this study, it was aimed to determine the rate of CMV seroprevalence in pregnant women, the prevalence of maternal CMV infection and also the incidence of congenital CMV infection in their newborns in the Kazeroon, south of Iran.Methods. Between January 2007 and July 2007, all (n = 1472) pregnant women who attended the obstetric ward of Valiasr hospital in Kazeroon for delivery, were enrolled in this study, and according to the presence or absence of anti CMV-IgM and CMV-IgG, were classified as seropositive, seronegative and having active maternal CMV infection. Differentiation of primary and recurrent CMV infection in women with both CMV-IgM (+) and CMV-IgG (+) antibody was determined by the avidity index (AI) of anti-CMV IgG.Results. The rate of seropositivity was found as 97.69% and the rate of seronegativity as 2.31% in pregnant women. The prevalence of active maternal CMV infection was found as 4.35% and among these pregnant women, the incidence of primary and recurrent maternal CMV infection was 34.4% and 65.6% respectively.Conclusion. Seroprevalence rate of CMV in pregnant women is high and most infections are recurrent. Thus, it does not seem to be cost-effective to screen all pregnant women for CMV infection, as in the other countries with high seropositivity rate. 相似文献
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Babbin S. John MRCS David Rowland MSc Uday Patel MRCP FRCR James Pilcher MRCP FRCR Ken Anson MS FRCS Dariush Nassiri MSc PhD FIPEM CSci 《Journal of ultrasound in medicine》2009,28(2):155-162
Objective. Three‐dimensional ultrasonography (3DUS) has recently become a reality because of advances in ultrasound probes and machine processing ability. We have developed an anthropomorphic phantom of the human loin to assess both the accuracy of 3DUS of the kidney and its potential usefulness for training in ultrasonographically guided percutaneous renal intervention. Methods. The model was built with easily available and inexpensive materials such as agar and latex with known ultrasonographic properties. The accuracy of 2‐dimensional ultrasonography (2DUS) and 3DUS was assessed by measuring the dimensions of the pelvicalyceal system (PCS) ultrasonographically (pelvis width and calyx diameters) and then comparing these with measurements obtained at the time of construction. Radiology interventional trainees then punctured the PCS with 2DUS and 4‐dimensional ultrasonographic (real‐time/time‐resolved 3DUS) guidance and reported the phantom's performance. Results. The 3‐dimensional nature of the model's PCS could be clearly visualized on 2DUS and 3DUS, and the scan characteristics were very similar to those in real life. Measurements using 3DUS proved to be closer to the true dimensions of the model's PCS than those using 2DUS. The mean error percentage for 2DUS measurements was ?10.2%, and that for 3DUS was ?2.2% (P < 0.0001). Interventional trainees were satisfied with the “tissue feel” and level of difficulty posed on puncturing the phantom. Conclusions. Three‐dimensional ultrasonography proved to be more accurate than 2DUS for intrarenal measurements using this in vitro renal model. Three‐dimensional ultrasonography has the potential to ease diagnostic renal scanning with the ability to further scrutinize and postprocess the scanned volumes. The model was realistic in its anthropomorphic properties and simulated human tissue during puncture. 相似文献