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91.
Ravi K. Garg MD Kenneth S. Lee MD Sarah C. Kohn BS Mustafa K. Baskaya MD Ahmed M. Afifi MD 《Journal of ultrasound in medicine》2015,34(11):2089-2091
Diagnostic tools for evaluating the supraorbital rim in preparation for nerve decompression surgery in patients with chronic headaches are currently limited. We evaluated the use of sonography to diagnose the presence of a supraorbital notch or foramen in 11 cadaver orbits. Sonographic findings were assessed by dissecting cadaver orbits to determine whether a notch or foramen was present. Sonography correctly diagnosed the presence of a supraorbital notch in 7 of 7 cases and correctly diagnosed a supraorbital foramen in 4 of 4 cases. We found that sonography had 100% sensitivity in diagnosing a supraorbital notch and foramen. This tool may therefore be helpful in characterizing the supraorbital rim preoperatively and may influence the decision to use a transpalpebral or endoscopic approach for supraorbital nerve decompression as well as the decision to use local or general anesthesia. 相似文献
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Sattler M Quinnan LR Pride YB Gramlich JL Chu SC Even GC Kraeft SK Chen LB Salgia R 《Blood》2003,102(1):289-296
The effect of 2-methoxyestradiol, 2ME2, an endogenous metabolite of 17beta-estradiol (E2), on cell growth and cytoskeletal functions in a BCR-ABL-transformed cell line model was investigated. We determined the interaction of 2ME2 with STI571 (Gleevec, imatinib mesylate) in STI571 drug-sensitive and -resistant cell lines. In cells expressing BCR-ABL, STI571 cooperated with 2ME2 in reducing cell growth, and STI571-resistant cells were sensitive to 2ME2 treatment. 2ME2 also inhibited growth of several cancer cell lines by a mechanism independent of BCR-ABL. BCR-ABL transformation leads to altered motility, increased adhesion, and spontaneous migration in different in vitro model systems. 2ME2 was found to specifically inhibit the spontaneous motility of BCRABL-transformed Ba/F3 cells and to change the morphology and volume of treated cells. Cells attached to fibronectin-coated surfaces showed a reduced number of filipodia and lamellipodia. In addition, 2ME2 significantly reduced BCRABL-mediated adhesion to fibronectin. The spontaneous migration of BCR-ABL-transformed cells through a transwell membrane also was found to be significantly decreased by 2ME2. Cytoskeletal changes were accompanied by alteration of tubulin formation, distinct from paclitaxel treatment. These results demonstrate that 2ME2 treatment of transformed cells strongly reduces cytoskeletal functions and may also be useful for the treatment of cancers with high metastatic potential. Combination of 2ME2 with other anticancer drugs may be beneficial to treatment of drug-resistant cancers. 相似文献
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Amelia Christabel Ravi Sharma R. Manikandhan P. Anantanarayanan N. Elavazhagan Pramod Subash 《Journal of maxillofacial and oral surgery》2015,14(2):154-161
Purpose
The aim of this paper is to review the pathophysiology of thermoregulation mechanism, various causes of fever after maxillofacial surgery and the different treatment protocols advised in the literature.Discussion
Fever is one of the most common complaints after major surgery and is also considered to be an important clinical sign which indicates developing pathology that may go unnoticed by the clinician during post operative period. Several factors are responsible for fever after the maxillofacial surgery, inflammation and infection being the commonest. However, other rare causes such as drug allergy, dehydration, malignancy and endocrinological disorders, etc. should be ruled out prior to any definite diagnosis and initiate the treatment. Proper history and clinical examination is an essential tool to predict the causative factors for fever. Common cooling methods like tepid sponging are usually effective alone or in conjunction with analgesics to reduce the temperature.Conclusion
Fever is a common postoperative complaint and should not be underestimated as it may indicate a more serious underlying pathology. A specific guideline towards the management of such patients is necessary in every hospital setting to ensure optimal care towards the patients during post operative period. 相似文献96.
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Vidya Sagar Sudheesh Pilakka‐Kanthikeel Ravi Pottathil Shailendra K. Saxena Madhavan Nair 《Reviews in medical virology》2014,24(2):103-124
Although highly active antiretroviral therapy (HAART) has resulted in remarkable decline in the morbidity and mortality in AIDS patients, controlling HIV infections still remain a global health priority. HIV access to the CNS serves as the natural viral preserve because most antiretroviral (ARV) drugs possess inadequate or zero delivery across the brain barriers. Thus, development of target‐specific, effective, safe, and controllable drug‐delivery approach is an important health priority for global elimination of AIDS progression. Emergence of nanotechnology in medicine has shown exciting prospect for development of novel drug delivery systems to administer the desired therapeutic levels of ARV drugs in the CNS. Neuron‐resuscitating and/or antidependence agents may also be delivered in the brain through nanocarriers to countercheck the rate of neuronal degradation during HIV infection. Several nanovehicles such as liposomes, dendrimers, polymeric nanoparticles, micelles, and solid lipid nanoparticles have been intensively explored. Recently, magnetic nanoparticles and monocytes/macrophages have also been used as carrier to improve the delivery of nanoformulated ARV drugs across the blood–brain barrier. Nevertheless, more rigorous research homework has to be elucidated to sort out the shortcomings that affect the target specificity, delivery, release, and/or bioavailability of desired amount of drugs for treatment of neuroAIDS. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Ryan C. Widau Akash D. Parekh Mark C. Ranck Daniel W. Golden Kiran A. Kumar Ravi F. Sood Sean P. Pitroda Zhengkai Liao Xiaona Huang Thomas E. Darga David Xu Lei Huang Jorge Andrade Bernard Roizman Ralph R. Weichselbaum Nikolai N. Khodarev 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(4):E484-E491
An siRNA screen targeting 89 IFN stimulated genes in 14 different cancer cell lines pointed to the RIG-I (retinoic acid inducible gene I)–like receptor Laboratory of Genetics and Physiology 2 (LGP2) as playing a key role in conferring tumor cell survival following cytotoxic stress induced by ionizing radiation (IR). Studies on the role of LGP2 revealed the following: (i) Depletion of LGP2 in three cancer cell lines resulted in a significant increase in cell death following IR, (ii) ectopic expression of LGP2 in cells increased resistance to IR, and (iii) IR enhanced LGP2 expression in three cell lines tested. Studies designed to define the mechanism by which LGP2 acts point to its role in regulation of IFNβ. Specifically (i) suppression of LGP2 leads to enhanced IFNβ, (ii) cytotoxic effects following IR correlated with expression of IFNβ inasmuch as inhibition of IFNβ by neutralizing antibody conferred resistance to cell death, and (iii) mouse embryonic fibroblasts from IFN receptor 1 knockout mice are radioresistant compared with wild-type mouse embryonic fibroblasts. The role of LGP2 in cancer may be inferred from cumulative data showing elevated levels of LGP2 in cancer cells are associated with more adverse clinical outcomes. Our results indicate that cytotoxic stress exemplified by IR induces IFNβ and enhances the expression of LGP2. Enhanced expression of LGP2 suppresses the IFN stimulated genes associated with cytotoxic stress by turning off the expression of IFNβ.Several studies have shown that the response of tumor cells to ionizing radiation (IR) is associated with IFN-mediated signaling (1–6). IFN signaling leads to the induction of multiple IFN stimulated genes (ISGs) (7, 8) and activates growth arrest and cell death in exposed cell populations (9). The precise mechanism of IR-mediated induction of IFN signaling is unknown. Tumor cell clones that survive an initial cytotoxic insult are subsequently resistant to exposure to both IR and prodeath components of IFN signaling (10). These clones express IFN-dependent enhanced levels of constitutively expressed ISGs, which overlap in part with ISGs initially induced by cytotoxic stress. Many of these constitutively expressed ISGs have been characterized as antiviral genes (11). Recently, enhanced levels of constitutively expressed ISGs have been reported in advanced cancers and were often associated with a poor prognosis related to aggressive tumor growth, metastatic spread, resistance to IR/chemotherapy, or combinations of these factors (11–18). The studies presented in this report are based on the hypothesis that a specific set of constitutively expressed ISGs, whose enhanced expression is by cytotoxic stress, confers a selective advantage to individual tumor clones (5, 9, 10, 13, 19).To test this hypothesis, we designed a targeted siRNA screen against 89 ISGs selected from two sources. The first included ISGs identified in our earlier screen and designated the IFN-Related DNA Damage Signature (IRDS) (1, 13). The second set included related ISG signatures that have been reported in the literature (as described in Methods and Dataset S1). The 89 genes were individually targeted in 14 tumor cell lines derived from malignant gliomas, lung, breast, colon, head and neck, prostate, and bladder cancers.The most significant finding from this screen was that the RNA helicase Laboratory of Genetics and Physiology 2 (LGP2) encoded by DHX58 [DEXH (Asp-Glu-X-His) box polypeptide 58] confers survival and mediates the response to IR of multiple tumor cell lines. LGP2 acts as a suppressor of the RNA-activated cytoplasmic RIG-I RIG-I (retinoic acid inducible gene I)–like receptor’s pathway (20, 21). This pathway is a subtype of pattern recognition receptors responsible for primary recognition of pathogen and host-associated molecular patterns and the subsequent activation of type I IFN production that orchestrates an innate immune response (22–24). In addition to its role in inhibiting IFNβ expression, Suthar et al. recently demonstrated that LGP2 governs CD8+ T-cell fitness and survival by inhibiting death-receptor signaling (25). Here we demonstrate that suppression of LGP2 leads to an enhanced IFNβ expression and increased killing of tumor cells. Our results thereby provide a mechanistic connection between IR-induced cytotoxic response in tumor cells and the LGP2–IFNβ pathway. 相似文献
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