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991.
Silva OA Silva PB Silva OV Braga GM Albuquerque Júnior A Queiros Neto V Rocha ME Silva EF 《Bulletin de la Societe de pathologie exotique (1990)》2007,100(1):49-50
In a rural area of Northeast Brazil, the relatively high serological infection by Leishmania in dogs, the lack of classical vector Lutzomyia longipalpis and of American Visceral Leishmaniasis cases in human beings and the observation of Leishmania in ticks collected in infected dogs suggest that ticks may be responsible for the transmission between dogs. 相似文献
992.
In this study, nonenzymatic glycosylation was assessed in aorta extracellular matrix (ECM) from nonobese diabetic (NOD) mice, using nitroblue tetrazolium (NBT). Molecular and structural changes were investigated in elastic lamellae and collagen fibers of diabetic mice aortas after staining with dansyl chloride and anilinonaphthalene sulfonate (ANS). Alterations in arterial autofluorescence and birefringence of collagen fibers were investigated in unstained aortas. Proliferation of smooth muscle cells (SMC) was also investigated by Feulgen reaction staining assessed by confocal microscopy and image analysis. Assessment of nonenzymatic glycosylation demonstrated glycosylation products in the aorta ECM of NOD mice. Elastic lamellae and collagen fibers from NOD mouse aortas presented less intense fluorescence after staining with dansyl chloride and ANS when compared to aortas of control nondiabetic mice. However, unstained NOD aortas showed more intense autofluorescence when compared to controls. Birefringence analysis suggests alterations in the higher molecular packing of the arterial collagen fibers in NOD aortas. In aortas stained by Feulgen reaction, no evidence of SMC proliferation was observed in diabetic aortas. 相似文献
993.
In the present experiments extracellular arginine, glutamate and aspartate were studied in the basolateral nucleus of the amygdala and core of the nucleus accumbens during the formalin test (phase I). A combination of capillary zone electrophoresis with laser induced fluorescence detection and microdialysis in freely moving rats was used. Glutamate and arginine significantly increased in the nucleus accumbens after formalin injection; glutamate, arginine and aspartate significantly increased in the basolateral nucleus of the amygdala, after formalin injection. These experiments suggest that rapid neurotransmitters changes observed in the nucleus accumbens and amygdala, are possibly related to immobility and emotional states such as anxiety, aversion and/or depression caused by pain. 相似文献
994.
Activation/modulation of adaptive immunity emerges simultaneously after 17DD yellow fever first-time vaccination: is this the key to prevent severe adverse reactions following immunization? 下载免费PDF全文
Martins MA Silva ML Marciano AP Peruhype-Magalhães V Eloi-Santos SM Ribeiro jG Correa-Oliveira R Homma A Kroon EG Teixeira-Carvalho A Martins-Filho OA 《Clinical and experimental immunology》2007,148(1):90-100
Over past decades the 17DD yellow fever vaccine has proved to be effective in controlling yellow fever and promises to be a vaccine vector for other diseases, but the cellular and molecular mechanisms by which it elicits such broad-based immunity are still unclear. In this study we describe a detailed phenotypic investigation of major and minor peripheral blood lymphocyte subpopulations aimed at characterizing the kinetics of the adaptive immune response following primary 17DD vaccination. Our major finding is a decreased frequency of circulating CD19+ cells at day 7 followed by emerging activation/modulation phenotypic features (CD19+interleukin(IL)10R+/CD19+CD32+) at day 15. Increased frequency of CD4+human leucocyte antigen D-related(HLA-DR+) at day 7 and CD8+HLA-DR+ at day 30 suggest distinct kinetics of T cell activation, with CD4+ T cells being activated early and CD8+ T cells representing a later event following 17DD vaccination. Up-regulation of modulatory features on CD4+ and CD8+ cells at day 15 seems to be the key event leading to lower frequency of CD38+ T cells at day 30. Taken together, our findings demonstrate the co-existence of phenotypic features associated with activation events and modulatory pathways. Positive correlations between CD4+HLA-DR+ cells and CD4+CD25high regulatory T cells and the association between the type 0 chemokine receptor CCR2 and the activation status of CD4+ and CD8+ cells further support this hypothesis. We hypothesize that this controlled microenviroment seems to be the key to prevent the development of serious adverse events, and even deaths, associated with the 17DD vaccine reported in the literature. 相似文献
995.
Lofrano-Porto A Barra GB Giacomini LA Nascimento PP Latronico AC Casulari LA da Rocha Neves Fde A 《The New England journal of medicine》2007,357(9):897-904
Selective luteinizing hormone deficiency due to mutations in the luteinizing hormone beta-subunit gene (LHB) is a rare cause of hypogonadism. We describe the clinical features of a consanguineous family in which three siblings, two men and one woman, had hypogonadism related to isolated luteinizing hormone deficiency. These subjects have a newly discovered homozygous mutation of a 5' splice site in LHB: IVS2+1G-->C. This mutation disrupts the splicing of messenger RNA (mRNA), generating a gross abnormality in the processing of the luteinizing hormone beta-subunit mRNA, which abrogates the secretion of luteinizing hormone. We also determined that the female phenotype of this LHB mutation is characterized by normal pubertal development, secondary amenorrhea, and infertility. 相似文献
996.
997.
Assessment and characterization of sound pressure levels in Portuguese neonatal intensive care units
Joana Santos Carlos Carvalhais Ana Xavier Manuela V. Silva 《Archives of environmental & occupational health》2018,73(2):121-127
In the NICU, systematic exposure to sound-pressure above the recommended level can affect both neonates and staff. This study aimed to evaluate the sound pressure levels in three Portuguese NICUs and the noise perceptions of staff. The measurements were performed with a sound-level meter, considering the location of the main sources of noise and the layout of the units. A questionnaire was applied to assess noise perceptions of professionals. Among the staff, 41.1% classified the environment (regarding noise) as “slightly uncomfortable”; 48.4% considered it as “acceptable.” The majority (55.5%) considered “equipment” the most annoying source of noise. The results showed that noise levels were excessive in all the evaluated areas of the NICUs, exceeding international guidelines, with levels ranging between 48.7 dBA to 71.7 dBA. Overall, there is a need for more research to verify the effectiveness of some actions and strategies to reduce the effect of noise in the NICU. 相似文献
998.
Ramon Oliveira Souza Tadeu Henrique de Lima Rodrigo Lambert Oréfice Marcelo Gonzaga de Freitas Araújo Sandra Aparecida de Lima Moura Juliana Teixeira Magalhães Gisele Rodrigues da Silva 《Journal of pharmaceutical sciences》2018,107(10):2674-2685
Vulvovaginal candidiasis is an inflammation localized in the vulvovaginal area. It is mostly caused by Candida albicans. Its treatment is based on the systemic and local administration of antifungal drugs. However, this conventional therapy can fail owing to the resistance of the Candida species and noncompliance of patients. Amphotericin B-loaded poly(lactic-co-glycolic acid) nanofibers are single-use, antifungal, controlled drug delivery systems, and represent an alternative therapeutic scheme for the local treatment of vulvovaginal candidiasis. Nanofibers were characterized by analytical techniques and with an in vitro drug delivery study. In vitro and in vivo fungicidal activity of amphotericin B released from nanofibers was evaluated using the agar diffusion method and an experimental murine model of vulvovaginal candidiasis, respectively. Analytical techniques showed that amphotericin B was physically mixed in the polymeric nanofibers. Nanofibers controlled the delivery of therapeutic doses of amphotericin B for 8 consecutive days, providing effective in vitro antifungal activity and eliminated the in vivo vaginal fungal burden after 3 days of treatment and with only one local application. Amphotericin B-loaded poly(lactic-co-glycolic acid) nanofibers could be potentially applied as an alternative strategy for the local treatment of vulvovaginal candidiasis without inducing fungal resistance, yet ensuring patient compliance. 相似文献
999.
Verônica M. Couto Maria J. Prieto Daniela E. Igartúa Daniela A. Feas Lígia N.M. Ribeiro Camila M.G. Silva Simone R. Castro Viviane A. Guilherme Darlene D. Dantzger Daisy Machado Silvia del V. Alonso Eneida de Paula 《Journal of pharmaceutical sciences》2018,107(9):2411-2419
Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 μM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC. 相似文献
1000.
Iman M.N. Hamdan Ismaiel A. Tekko Kyle B. Matchett Luis G. Arnaut Claudia S. Silva Helen O. McCarthy Ryan F. Donnelly 《Journal of pharmaceutical sciences》2018,107(9):2439-2450
Nodular basal cell carcinoma is a deep skin lesion and one of the most common cancers. Conventional photodynamic therapy is limited to treatment of superficial skin lesions. The parenteral administration of near-IR preformed photosensitizers suffers from poor selectivity and may result in prolonged skin photosensitivity. Microneedles (MNs) can provide localized drug delivery to skin lesions. Intradermal delivery of the preformed near-IR photosensitizer; 5,10,15,20-tetrakis(2,6-difluoro-3-N-methylsulfamoylphenyl bacteriochlorin (Redaporfin?) using dissolving MN was successful in vitro and in vivo. MN demonstrated complete dissolution 30 min after skin application and showed sufficient mechanical strength to penetrate the skin to a depth of 450 μm. In vitro deposition studies illustrated that the drug was delivered and detected down to 5 mm in skin. In vivo biodistribution studies in athymic nude mice Crl:NU(NCr)-Foxn1nu showed both fast initial release and localized drug delivery. The MN-treated mice showed a progressive decrease in the fluorescence intensity at the application site over the 7-day experiment period, with the highest and lowest fluorescence intensities measured being 9.2 × 1010 ± 2.5 × 1010 and 3.8 × 109 ± 1.6 × 109 p/s, respectively. By day 7, there was some migration of fluorescence away from the site of initial MN application. However, the majority of the body surfaces showed fluorescence levels that were comparable to those seen in the negative control group. This work suggests utility for polymeric MN arrays in minimally invasive intradermal delivery to enhance photodynamic therapy of deep skin lesions. 相似文献