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901.
902.
Rebecca P. Hill Aaron Gardner Heather C. Crawford Rachel Richer Anna Dodds William A. Owens Clifford Lawrence Sam Rao Bo Kara S. Elizabeth James Colin A. Jahoda 《Experimental dermatology》2013,22(3):236-238
Traditional skin grafting techniques are effective but limited methods of skin replacement. Autologous transplantation of rapidly cultured keratinocytes is successful for epidermal regeneration, but the current gold‐standard technique requires mouse fibroblast feeders and serum‐rich media, with serum‐free systems and dermal fibroblast (DF) feeders performing relatively poorly. Here, we investigated the capacity of human hair follicle dermal cells to act as alternative supports for keratinocyte growth. Dermal papilla (DP) dermal sheath (DS), DF and 3T3 cells were used as inactivated feeder cells for human keratinocyte coculture. Under conditions favouring dermal cells, proliferation of keratinocytes in the presence of either DS or DP cells was significantly enhanced compared with DF cells, at levels comparable to keratinocytes cultured under gold‐standard conditions. Secreted protein acidic and rich in cysteine (SPARC) expression increased DS and DP cells relative to DFs; however, further experiments did not demonstrate a role in keratinocyte support. 相似文献
903.
Monique G. Kumar M.Phil. M.D. Heather Ciliberto M.D. Susan J. Bayliss M.D. 《Pediatric dermatology》2015,32(2):198-200
Pediatric trachyonychia is an acquired nail disease that can cause distress to families. It is a poorly understood disease, and long‐term follow‐up data are lacking. We present an institutional review of 11 children with isolated pediatric trachyonychia followed over time. Children with the diagnosis of pediatric trachyonychia were identified and invited to participate. Pictures were taken on follow‐up and a questionnaire was answered. Exclusion criteria include having another diagnosis at the initial visit that causes nail dystrophy. Eleven patients with the diagnosis of pediatric trachyonychia were available for follow‐up. The mean age of appearance was 2.7 years (range 2–7 yrs) and the average follow‐up was 66 months (range 10–126 mos). Nine patients were treated with potent topical corticosteroids, one used only petrolatum, and one took vitamin supplements. One patient was found to have an additional skin and hair diagnosis of alopecia areata on follow‐up. On follow‐up, 82% noted improvement of the nails, whereas 18% noted no change. A majority of cases of pediatric trachyonychia are isolated and improve with time, regardless of treatment. 相似文献
904.
D. H. Krüger Sigrid Hansen W. Presber M. Rudolph D. Scholz H. A. Rosenthal 《Journal of basic microbiology》1979,19(7):473-480
The closely related phages T3 and T7 exhibit different growth patterns on Escherichia coli W host cells (E. coli K12 derivatives). T7 grows normally while T3 does not adsorb. T3hw mutants displaying a T7-like host range were isolated and described. 相似文献
905.
Heat shock protein 90 inhibition sensitizes acute myelogenous leukemia cells to cytarabine 下载免费PDF全文
Mesa RA Loegering D Powell HL Flatten K Arlander SJ Dai NT Heldebrant MP Vroman BT Smith BD Karp JE Eyck CJ Erlichman C Kaufmann SH Karnitz LM 《Blood》2005,106(1):318-327
Previous studies demonstrated that ataxia telangiectasia mutated- and Rad3-related (ATR) kinase and its downstream target checkpoint kinase 1 (Chk1) facilitate survival of cells treated with nucleoside analogs and other replication inhibitors. Recent results also demonstrated that Chk1 is depleted when cells are treated with heat shock protein 90 (Hsp90) inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG). The present study examined the effects of 17-AAG and its major metabolite, 17-aminogeldanamycin (17-AG), on Chk1 levels and cellular responses to cytarabine in human acute myelogenous leukemia (AML) cell lines and clinical isolates. Cytarabine, at concentrations as low as 30 nM, caused activating phosphorylation of Chk1, loss of the phosphatase Cdc25A, and S-phase slowing. Conversely, treatment with 100 to 300 nM 17-AAG for 24 hours caused Chk1 depletion that was accompanied by diminished cytarabine-induced S-phase accumulation, decreased Cdc25A degradation, and enhanced cytotoxicity as measured by inhibition of colony formation and induction of apoptosis. Additional studies demonstrated that small inhibitory RNA (siRNA) depletion of Chk1 also sensitized cells to cytarabine, whereas disruption of the phosphatidylinositol 3-kinase (PI3k) signaling pathway, which is also blocked by Hsp90 inhibition, did not. Collectively, these results suggest that treatment with 17-AAG might represent a means of reversing checkpoint-mediated cytarabine resistance in AML. 相似文献
906.
907.
OBJECTIVE: In order to enable clinicians to refer the right persons suspected of familial hypercholesterolemia (FH) for mutation screening, a retrospective study was conducted in a Danish FH cohort. DESIGN AND METHODS: The study comprised 643 probands and 395 relatives, of which 421 individuals had a pathogenic mutation, and 211 had cardiovascular disease (CVD). Logistic regression, Cox regression, and receiver operating characteristics (ROC) curves were used to find optimal predictive variables for mutation status and evaluate risk factors for CVD. RESULTS: Age alone had significant predictive power in both genders. ROC curves and area under the curve plots found no parameters capable of predicting mutation status. The only significant risk factor for CVD in both genders was mutation carrier status. CONCLUSIONS: No parameters could decipher mutation status a priori. All individuals fulfilling the FH criteria should therefore be referred in order to facilitate family tracing and genetic counseling. 相似文献
908.
909.
Alexis Sentís Irina Kislaya Nathalie Nicolay Hinta Meijerink Jostein Starrfelt Ivn Martínez-Baz Jesús Castilla Katrine Finderup Nielsen Christian Holm Hansen Hanne-Dorthe Emborg Anthony Nardone Tarik Derrough Marta Valenciano Baltazar Nunes Susana Monge the VEBIS-Lot working group VEBIS-Lot working group Ausenda Machado Carlos Dias Itziar Casado Cristina Burgui Amparo Larrauri Clara Mazagatos 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(30)
By employing a common protocol and data from electronic health registries in Denmark, Navarre (Spain), Norway and Portugal, we estimated vaccine effectiveness (VE) against hospitalisation due to COVID-19 in individuals aged ≥ 65 years old, without previous documented infection, between October 2021 and March 2022. VE was higher in 65–79-year-olds compared with ≥ 80-year-olds and in those who received a booster compared with those who were primary vaccinated. VE remained high (ca 80%) between ≥ 12 and < 24 weeks after the first booster administration, and after Omicron became dominant. 相似文献
910.