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81.
Sarcoidosis is a multisystemic disease that usually involves the lungs and lymph nodes, but almost any organ can be involved. Genitourinary involvement with sarcoidosis is extremely rare. We report the case of a 30-year-old African-American male who presented with a right-sided intrascrotal mass and diffuse lymphadenopathy. On further workup, he was found to have sarcoidosis. Two months of corticosteroid treatment resulted in the disappearance of his intrascrotal mass.  相似文献   
82.
A wide range of quinazolin-4(3H)-ones have been synthesized from readily accessible precursors such as anthranilamide and 1,3-diketones. This reaction was promoted by the heterogeneous beta zeolite as the catalyst via a selective cleavage of the C–C bond of 1,3-diketones. This reaction went smoothly with various 1,3-diketones (cyclic and acyclic) affording 2-aryl and 2-alkyl substituted quinazolin-4(3H)-ones in good to excellent yields. The notable point of this strategy is that it can avoid the involvement of toxic transition metals, additives and corrosive oxidants establishing this method as green and feasible. Besides, this method displays its capacity for gram-scale reactions (up to 10 g). Moreover, in this process the recyclability of the recovered catalyst without drastic changes until 5 cycles have been presented.  相似文献   
83.
Neonatal chylothorax is a relatively uncommon condition. Here we describe the case of an extremely preterm infant with bilateral chylous effusions which were resistant to conventional medical management and were ultimately managed with the insertion of pleuroperitoneal shunts using a novel surgical technique. Subsequently the infant recovered and the shunts could be removed. We report this case to highlight that such shunts can be inserted even in tiny preterm infants with minimally invasive techniques, and be extremely successful in managing chylothorax, pending spontaneous recovery. Pediatr. Pulmonol. 2010; 45:840–843. © 2010 Wiley‐Liss, Inc.  相似文献   
84.
Stereotactic irradiation, either in the form of stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) of brain lesions requires high precision and submillimetre accuracy in the isocentre, the main determinants being gantry and couch rotations. It is thus necessary to evaluate the isocentre variation due to gantry and couch rotations in the particular setup for SRS/SRT. This paper describes variation in the isocentre of a Philips (now Elekta) SL-20 linear accelerator modified for adapting a couch-mounted radiosurgery system. By considering the isocentre as defined by a mechanical index as the standard, the variations in the isocentre of the linear accelerator were independently measured for the gantry and for couch rotations. The variation in the isocentre for gantry rotation was found to be between 0.1 mm and 0.9 mm, conforming to the submillimetre accuracy required for SRS/SRT. However, the isocentre variation due to couch rotation varied considerably, possibly because the couch is of the RAM type. The isocentre variation due to couch rotation is rectified by microadjusting the couch mount at the time of treatment using a laser target localizing frame. It is our conclusion that a modified linear accelerator can be used for performing SRS/SRT after careful and separate evaluation of the isocentre stability due to gantry and couch rotations.  相似文献   
85.
86.
During the process development of docetaxel, two polar impurities (Impurities I and II) and two non-polar impurities (Impurities III and IV) were detected by high performance liquid chromatography (HPLC). All the impurities were isolated by Medium Pressure Liquid Chromatography (MPLC). The Impurities I, II, III and IV were identified as 13-[(4S,5R)-2-oxo-4-phenyl-oxazolidine-5-carboxy]-10-deacetyl baccatin III ester, 2'-epi docetaxel, 7-epi docetaxel and 13-[(4S,5R)-2-oxo-4-phenyl-oxazolidine-3,5-dicarboxyl-3-tert-butyl)]-10-deacetyl baccatin III ester, respectively, based on one- (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy data. The Impurity IV was crystallized and the structure was solved by single crystal X-ray diffraction (XRD). Two impurities (Impurities II and III) were found to be process related, while the remaining two impurities (Impurities I and IV) turned out to be isomers. The formation of these impurities was discussed.  相似文献   
87.
Background: This study was undertaken to identify and quantify the class and subclass antibody responses to the culture filtrate antigen (CFA) of Burkholderia pseudomallei in melioidosis patients under long-term maintenance or eradication therapy. Materials and Methods: Sequential sera samples from seven melioidosis patients collected between January 1992 and April 1998 were analyzed for immunoglobulin (Ig) types and IgG isotypes by ELISA using B. pseudomallei CFA. Results: Melioidosis patients generated a strong IgG, IgA and IgM response to the CFA of B. pseudomallei throughout the infection and IgG1 and IgG2 were the predominant IgG istotypes produced. Although high levels of these antibodies were detected in all the seven patients, the IgG, IgG1 and IgG2 antibodies showed a consistent response and good correlation with the clinical history in all cases. Conclusion: This study suggests that monitoring IgG antibody or IgG1 or IgG2 isotype antibody levels to CFA in patients under maintenance or eradication antibiotic therapy may be useful as a tool to detect the status of infection and as a guideline to determine the duration of maintenance antimicrobial therapy. Received: February 4, 2002 · Revision accepted: October 6, 2002 C. Vasu (corresponding author)  相似文献   
88.
89.
Heart failure affects 5 million persons in the United States, with 400,000 new cases occurring every year. Paradoxically, although advances in coronary angioplasty and effective drugs have increased survival post infarction, the myocardial damage and subsequent neurohormonal activation-induced remodeling causes significant morbidity years later in the form of heart failure. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) together with beta blockers modify the neurohormonal activation associated with heart failure and are key treatments for improving cardiac function and survival. Anemia is a significant risk factor predicting morbidity and mortality in heart failure. This article describes the various etiologies of anemia in heart failure. Of particular importance is the fact that recent stem cell studies have shown that the drugs acting on the renin-angiotensin system inhibit erythropoiesis in vivo and may cause anemia in patients with both normal renal function and end-stage renal disease (ESRD). The role of angiotensin-II as an erythropoietic growth factor and ACE in facilitating erythropoiesis is described in this article. Anemia has been shown to be a modifiable risk factor and its treatment correlates with improvement in clinical outcomes. Thus, anemia, its etiology (especially the contribution of ACEIs and ARBs), physiologic and prognostic impact, and treatment in the setting of heart failure are critical areas for investigation.  相似文献   
90.
CD80 and CD86 expressed on the surface of antigen-presenting cells interact with cytotoxic T lymphocyte antigen-4 [CTLA-4 (CD152)] expressed on activated T cells and mediate critical T cell inhibitory signals. CD80 and CD86 are type I glycoproteins, and are made up of two extracellular (EC) Ig-like domains-a transmembrane region and a cytoplasmic tail. The N-terminal (V domain) and membrane-proximal (C) domains share homology with the variable region (V) and the constant region (C) of Ig respectively. Co-crystallographic structures of both CD80 and CD86 bound to CTLA-4 indicate that there is no direct interaction of the C domain of either CD80 or CD86 with the CTLA-4. In contrast, previous mutagenesis studies have identified specific amino acids within the C domain of CD80 that are critical for CTLA-4 binding. To further understand the importance of C domains in the functioning of CD80 and CD86, we constructed chimeric human CD80 and CD86 molecules by swapping their respective C domains, and tested their ability to stimulate T cells. A Chinese hamster ovary (CHO) cell line expressing CD86 activated murine T cells. In contrast, CHO cells expressing either CD80 or a chimeric construct of the CD86 V domain and the CD80 C domain showed a significantly reduced activation. Our studies further demonstrated that the decreased activation by cells expressing the CD80 or a chimera containing CD80 C domain is most likely due to enhanced CTLA-4 binding. From these results we conclude that C domains play a critical, albeit indirect, role in determining CTLA-4 binding affinities and co-stimulatory properties.  相似文献   
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