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81.
Papillary endothelial hyperplasia (PEH) is a benign process characterized by endothelial cell proliferation in a papillary pattern, usually occurring in reaction to traumatic vascular stasis or a thrombus. Commonly found in the soft tissues of the neck and extremities, intracardiac lesions in the left atrium, left ventricle, and coronary atherotomy specimens associated with trauma or thrombus have rarely been reported. A single prior report of a pure, isolated form of intracardiac PEH in the literature is noted. To the best of our knowledge, the imaging characteristics have not been described. We describe the dynamic magnetic resonance characteristics of a pure, isolated PEH occurring in the right ventricle. 相似文献
82.
Mohammad A. Javaid Mohamed-Nur Abdallah Ahad S. Ahmed Zeeshan Sheikh 《Acta neurologica Belgica》2013,113(4):381-390
Matrix metalloproteinases (MMPs) are a family of extracellular proteases associated with extracellular matrix remodeling. They are involved in many physiological and reparative processes. MMPs can break down all extracellular constituents; therefore, their expression is very tightly regulated and their abnormal activity or over production has been linked to many diseases including multiple sclerosis (MS) which is a leading cause of non-traumatic disability in young adults in North America. Recently many studies, both in animals and humans, have been conducted to better elucidate the underlying causes, mechanisms and pathophysiology of MS. In this review, we discuss the potential role of pathological upregulation of MMPs in MS and future challenges which if properly addressed might help in development of potential cure for this disease. 相似文献
83.
Somayeh Tajik Hadi Beitollahi Fariba Garkani Nejad Iran Sheikh Shoaie Mohammad A. Khalilzadeh Mehdi Shahedi Asl Quyet Van Le Kaiqiang Zhang Ho Won Jang Mohammadreza Shokouhimehr 《RSC advances》2020,10(62):37834
Scientists have categorized conductive polymers as materials having strongly reversible redox behavior and uncommon combined features of plastics and metal. Because of their multifunctional characteristics, e.g., simplistic synthesis, acceptable environmental stability, beneficial optical, electronic, and mechanical features, researchers have largely considered them for diverse applications. Therefore, their capability of catalyzing several electrode reactions has been introduced as one of their significant features. A thin layer of the conducting polymer deposited on the substrate electrode surface can augment the electrode process kinetics of several solution species. Such electrocatalytic procedures with modified conducting polymer electrodes can create beneficial utilization in diverse fields of applied electrochemistry. This review article explores typical recent applications of conductive polymers (2016–2020) as active electrode materials for energy storage applications, electrochemical sensing, and conversion fields such as electrochemical supercapacitors, lithium-ion batteries, fuel cells, and solar cells.Scientists have categorized conductive polymers as materials having strongly reversible redox behavior and uncommon combined features of plastics and metal. 相似文献
84.
Osman Ahmed Shermeen Sheikh Patrick Tran Brian Funaki Alexandria M. Shadid Rakesh Navuluri Thuong Van Ha 《Journal l'Association canadienne des radiologistes》2019,70(4):367-382
Inferior vena cava filters are commonly encountered devices on diagnostic imaging that were highlighted in a 2010 Food and Drug Administration safety advisory regarding their complications from long-term implantation. The Predicting the Safety and Effectiveness of Inferior Vena Cava Filters (PRESERVE) trial is an ongoing after-market study investigating the safety and utility of commonly utilized filters in practice today. While most of these filters are safe, prompt recognition and management of any filter-associated complication is imperative to prevent or reduce the morbidity and mortality associated with them. This review is aimed at discussing the appropriate utilization and placement of inferior vena cava filters in addition to the recognition of filter-associated complications on cross-sectional imaging. An overview of the PRESRVE trial filters is also provided to understand each filter's propensity for specific complications. 相似文献
85.
Dana Anaïs Muin Michael Wolzt Safoura Sheikh Rezaei Max Tremmel-Scheinost Mohamed Salama Carola Fuchs 《The European journal of contraception & reproductive health care》2016,21(2):141-149
Objectives The aim of the trial was to assess the effect of self-evaluation and sexual diary keeping on female sexual function and depressive symptoms in women diagnosed with sexual dysfunction.Methods A single-arm non-randomised trial included 30 women (53 ± 7 years of age) with female sexual dysfunction (Female Sexual Function Index [FSFI] < 27) and a stable partnership duration of 5–40 years. Female sexual function was assessed by sexual, psychological and gynaecological history taking and validated questionnaires including the FSFI, Female Sexual Distress Scale (FSDS) and Hamilton Depression Scale (HDS), before and after 4 weeks of sexual diary keeping.Results A subjective improvement in communication of sexual problems was reported by 60% of participants; no participants reported any worsening of communication. FSFI and FSDS scores were, respectively, 18.0 ± 7.7 and 22.0 ± 10.0 at baseline and 20.2 ± 7.2 and 20.6 ± 11.5 after 4 weeks. HDS score decreased from 6.0 ± 4.0 at baseline to 4.4 ± 2.7 after 4 weeks (p = 0.042).Conclusions Self-evaluation and sexual diary keeping may improve aspects of sexual life, such as couple communication, without a direct effect on variables measured with validated questionnaires on different domains of sexual function. 相似文献
86.
Saeed SA Shad KF Simjee SU 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,178(4):560-564
Thromboxane A2 (TXA2) formed in damaged brain tissue and after thromboembolism and subarachnoid haemorrhage is responsible for cerebral vasospasm.
In the present study, we examined the effect of human cerebrospinal fluid (CSF) on the production of thromboxane-A2 (TXA2) and 12-hydroxy-eicosatetraenoic acid (12-HETE) by human blood platelets. CSF was drawn by lumbar puncture from normal healthy
volunteers (n = 17) and samples judged to be normal after routine examination in the clinical laboratories and were used fresh. We found
that CSF inhibited the production of TXA2 and 12-HETE by blood platelets incubated with C14 labelled arachidonic acid (AA) in a concentration-related manner. Further biochemical analysis using proteolytic enzymes,
gel filtration and membrane partition chromatography showed that the inhibitory activity was peptidic in nature and associated
with a peptide of low molecular weight (1,400 Da). This study is the first to demonstrate that human CSF contains a dual inhibitor
of cyclooxygenase (COX) and lipoxygenase enzymes in CSF. 相似文献
87.
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89.
Ilias Nikolakopoulos MD James W. Choi MD Khaldoon Alaswad MD Jaikirshan J. Khatri MD Oleg Krestyaninov MD Dmitrii Khelimskii MD Robert W. Yeh MD PhD Farouc A. Jaffer MD PhD Catalin Toma MD Mitul Patel MD Ehtisham Mahmud MD Nicholas J. Lembo MD Manish Parikh MD Ajay J. Kirtane MD SM Ziad A. Ali MD Fotis Gkargkoulas MD Barry Uretsky MD Abdul M. Sheikh MD Evangelia Vemmou MD Iosif Xenogiannis MD Bavana V. Rangan BDS MPH Santiago Garcia MD Shuaib Abdullah MD Subhash Banerjee MD M. Nicholas Burke MD Emmanouil S. Brilakis MD PhD Dimitri Karmpaliotis MD PhD 《Catheterization and cardiovascular interventions》2021,97(4):658-667
90.
Farhana Yasmin Khairul Fikri Tamrin Nadeem Ahmed Sheikh Pierre Barroy Abdullah Yassin Amir Azam Khan Shahrol Mohamaddan 《Materials》2021,14(5)
Laser-assisted high speed milling is a subtractive machining method that employs a laser to thermally soften a difficult-to-cut material’s surface in order to enhance machinability at a high material removal rate with improved surface finish and tool life. However, this machining with high speed leads to high friction between workpiece and tool, and can result in high temperatures, impairing the surface quality. Use of conventional cutting fluid may not effectively control the heat generation. Besides, vegetable-based cutting fluids are invariably a major source of food insecurity of edible oils which is traditionally used as a staple food in many countries. Thus, the primary objective of this study is to experimentally investigate the effects of water-soluble sago starch-based cutting fluid on surface roughness and tool’s flank wear using response surface methodology (RSM) while machining of 316 stainless steel. In order to observe the comparison, the experiments with same machining parameters are conducted with conventional cutting fluid. The prepared water-soluble sago starch based cutting fluid showed excellent cooling and lubricating performance. Therefore, in comparison to the machining using conventional cutting fluid, a decrease of 48.23% in surface roughness and 38.41% in flank wear were noted using presented approach. Furthermore, using the extreme learning machine (ELM), the obtained data is modeled to predict surface roughness and flank wear and showed good agreement between observations and predictions. 相似文献