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81.
Preeti Oswal Aayushi Arora Jolly Kaushal Gyandshwar Kumar Rao Sushil Kumar Ajai K. Singh Arun Kumar 《RSC advances》2019,9(39):22313
Two chalcogenated ligands L1 and L2 containing anthracene core and amine functionality have been synthesized. Both the ligands have been characterized using 1H and 13C{1H} NMR techniques. The structure of L1 has also been corroborated by single crystal X-ray diffraction. Application of L1 and L2 as stabilizers for palladium nano-particles (NPs) has been explored and six different types of NPs 1–6 have been prepared by varying the quantity of stabilizer. The nano-particles have been characterized by PXRD, EDX, and HRTEM techniques. The size of NPs has been found to be in the range of ∼1–2 nm, 2–3 nm, 4–6 nm, 1–2 nm, 1–2 nm and 3–5 nm for 1–6 respectively. The catalytic activities of 1–6 have been explored for Suzuki–Miyaura coupling of phenyl boronic acid with various aryl halides. These NPs showed good catalytic activity for various aryl chlorides/bromides at low catalyst loading (5 mg). Among 1–6, the highest activity has been observed for NPs 1, probably due to their relatively small size and high uniformity in the dispersion. The recyclability of the NPs upto 5 catalytic cycles is a distinct advantage.Monodispersed ultrasmall Pd nanoparticles synthesized utilizing bulky organochalcogen secondary amines as stabilizers and application in Suzuki coupling of aryl chlorides at low catalyst loading. 相似文献
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Abraham Samuel Babu Kushal Madan Sundar Kumar Veluswamy Rahul Mehra Arun G. Maiya 《Progress in cardiovascular diseases》2014
Worksite health and wellness (WH&W) are gaining popularity in targeting cardiovascular (CV) risk factors among various industries. India is a large country with a larger workforce in the unorganized sector than the organized sector. This imbalance creates numerous challenges and barriers to implementation of WH&W programs in India. Large scale surveys have identified various CV risk factors across various industries. However, there is scarcity of published studies focusing on the effects of WH&W programs in India. This paper will highlight: 1) the current trend of CV risk factors across the industrial community, 2) the existing models of delivery for WH&W in India and their barriers, and 3) a concise evidence based review of various WH&W interventions in India. 相似文献
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Rupesh Raina Shyam Polaconda Nikhil Nair Ronith Chakraborty Sidharth Sethi Vinod Krishnappa Gaurav Kapur Maroun Mhanna Kirsten Kusumi 《Journal of clinical hypertension (Greenwich, Conn.)》2020,22(6):1059-1069
The morbidity and mortality of adult and pediatric chronic kidney disease (CKD) and end‐stage renal disease (ESRD) populations are mainly driven by cardiovascular disease (CVD). Improving CVD outcomes focuses on risk assessment of factors including diastolic blood pressure (DBP), systolic blood pressure (SBP), left ventricular mass index (LVMI), pulse pressure (PP), and pulse pressure index (PPi), which is calculated as PP/SBP. These markers are also proven predictors of CKD progression; however, their role in children has not been established. This study aims to evaluate the relationship between PP, PPi, ambulatory arterial stiffness index (AASI), and proteinuria with kidney function in pediatric CKD patients; it is a retrospective analysis of 620 patients (1‐16 years) from the NIDDK Chronic Kidney Disease in Children (CKiD) registry. The authors analyzed data for three separate cohorts: an overall CKD as well as immunological versus non‐immunological cause for CKD groups. An inverse relationship was found between SBP, DBP, and PP with iGFR and LVMI in the overall CKD group. Our immunological CKD subgroup showed significantly higher serum creatinine, SBP, DBP, and PP values with significantly lower serum albumin levels compared to the non‐immunological group. There were no significant differences with iohexol‐based glomerular filtration rate (iGFR), LVMI, PPi, or high‐sensitivity C‐reactive protein (hs‐CRP) between the two groups. A subgroup analysis demonstrated that SBP, DBP, and PP all correlated significantly with LVMI in the immunological CKD patients but not the non‐immunological subgroup. Additionally, AASI data in the overall CKD population were significantly correlated with PP, PPi, and DBP. This study is one of the first to correlate noninvasive measurements of vascular compliance including PP, PPi, and AASI with iGFR and LVMI in a pediatric CKD cohort. Improving our understanding of surrogate markers for early CVD is integral to improving the care of pediatric CKD population as these patients have yet to develop the hard end points of ESRD, heart failure, myocardial infarction, or stroke. 相似文献
86.
Duan C Karnik R Lu MC Majumdar A 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(10):3688-3693
Cavitation, known as the formation of vapor bubbles when liquids are under tension, is of great interest both in condensed matter science as well as in diverse applications such as botany, hydraulic engineering, and medicine. Although widely studied in bulk and microscale-confined liquids, cavitation in the nanoscale is generally believed to be energetically unfavorable and has never been experimentally demonstrated. Here we report evaporation-induced cavitation in water-filled hydrophilic nanochannels under enormous negative pressures up to -7 MPa. As opposed to receding menisci observed in microchannel evaporation, the menisci in nanochannels are pinned at the entrance while vapor bubbles form and expand inside. Evaporation in the channels is found to be aided by advective liquid transport, which leads to an evaporation rate that is an order of magnitude higher than that governed by Fickian vapor diffusion in macro- and microscale evaporation. The vapor bubbles also exhibit unusual motion as well as translational stability and symmetry, which occur because of a balance between two competing mass fluxes driven by thermocapillarity and evaporation. Our studies expand our understanding of cavitation and provide new insights for phase-change phenomena at the nanoscale. 相似文献
87.
The method that we use has an initial cost (£ 150) and uses fewer materials for dressing daily than other methods. It is easy to use at the extremities and is effective in preventing amputation in some diabetics. 相似文献
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