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1.
Emeline Colomba Patricia Pautier Fanny Pommeret Alexandra Leary 《Expert review of anticancer therapy》2019,19(6):437-446
Introduction: The landscape of poly (ADP-ribose) polymerase (PARP) inhibition in ovarian cancer is rapidly evolving and becoming increasingly complex. Ovarian cancer is leading therapeutic innovation by providing the proof of concept for DNA repair as a target. Three different PARP inhibitors have now received approvals in the US and Europe in different indications. Subtle but crucial differences can be found among the licensed indications for each PARP inhibitor in terms of histology, type of BRCA mutation (germline and/or somatic), number of prior lines of chemotherapy and whether the indication is in the treatment or maintenance settings.
Areas covered: We review the latest clinical data regarding the PARP inhibitor rucaparib in ovarian cancer, provide an update on the evolving landscape of PARP inhibition in ovarian cancer, and summarize avenues of ongoing and future research.
Expert opinion: All eligible patients should be offered a PARP inhibitor. SOLO1 trial results demonstrated an unprecedented benefit maintenance with PARP inhibitors in first line. Results from trials evaluating PARP inhibitors as maintenance in first line regardless of BRCA status and from trials evaluating combinatorial strategies are eagerly awaited. 相似文献
2.
Macrophages, dendritic cells or B lymphocytes have been shownto play a major role in the presentation of soluble antigensto CD4+ T cells. In contrast, the capacity of these cells topresent particulate antigens such as bacterial or parasiticantigens to T cells remains controversial. To investigate thisquestion, well defined particulate antigens were prepared bycovalent linkage of proteins or peptides to 1 µm in diametersynthetic microspheres. The T cell immunogenicity of such particulateantigens was analyzed in vitro and in vivo. In vitro, a solubleprotein such as hen egg lysozyme (HEL) coupled to beads stimulateda strong proliferative T cell response of lymph node cells fromHEL-primed mice or of specific T cell hybridomas. HEL coupledto beads was presented to the specific T cell hybridomas bysplenocytes or by peritoneal macrophages, but not by lymphomaB cells. Immunization of mice with several different proteinantigens or with a synthetic peptide covalently linked to beadsinduced strong CD4+ T cell responses in the absence of adjuvant.The strong in vivo immunogenicity of proteins coupled to beadsdid not result from a non-specific adjuvant effect of beadssince covalent linkage of the antigen to beads was strictlyrequired to induce T cell responses in the absence of adjuvant.In vivo treatment by carrageenan showed that macrophages arerequired for the in vivo stimulation of T cell responses bythese particulate antigens. Thus, these results demonstratedthe role of phagocytic cells, especially macrophages, for invivo presentation of particulate antigens. These particulateantigens represent an interesting approach for the developmentof new vaccines, and for the in vivo analysis of the role ofvarious antigen presenting cells in T cell activation and differentiation. 相似文献
3.
目的 探讨人工合成成骨生长肽 (sOGP)对辐射损伤小鼠造血功能的保护作用 ,阐明其剂量 效应关系。方法 以 4 .0和 7.5Gy13 7Csγ射线照射小鼠为模型 ,采用皮下注射和肌肉注射 2种给药途径连续 8d给予sOGP ,剂量范围为 0 .0 39~ 6 4 0nmol/(kg·d) ,观察外周血象、骨髓有核细胞数、骨髓粒系造血祖细胞集落形成(CFU G)、骨髓细胞分类和骨髓切片组织学等的变化。结果 sOGP能加快受照小鼠外周血白细胞、骨髓有核细胞数的恢复 ,在一定的剂量范围内呈明显的剂量依赖性 ,并能刺激髓外造血 ;促进 (CFU G)形成作用显著高于重组人粒系集落刺激因子 (rhG CSF)约 2倍 ;骨髓病理学观察显示sOGP能加快受照小鼠骨髓造血组织损伤的恢复 ,刺激骨髓粒系增生。结论 sOGP可明显促进受照射小鼠造血功能的恢复 ,其机制可能是通过作用于早期造血阶段或 (及 )改善微环境进而促进造血。 相似文献
4.
Y. TRUDELLE A. BRACK A. DELMAS S. PEDOUSSAUT P. RIVAILLE 《Chemical biology & drug design》1987,30(1):54-60
Sequential poly(Arg-Thr-Lys-Pro) consisting mainly of the repeat of tuftsin Thr-Lys-Pro-Arg was synthesized by condensing the p-nitrophenyl ester of Arg(HCI)-Thr-Lys-(2-CI-Z)-Pro in the presence of HOBt . Two haptenic sequences of the Pre-S region of hepatitis B virus antigen (10–26 and 39–55) were prepared by solid phase and coupled to polytuftsin via glutaraldehyde. The peptides, either free or coupled to polytuftsin, were administrated to mice and the antisera were assayed by ELISA . Coupling the peptides to the polypeptide significantly improved the anti-peptide antibody titer in Freund complete adjuvant or in NaCI 0.9%. Cross-reaction between antibodies induced by the peptides and the native protein was also improved. Polytuftsin alone is very poorly immunogenic. 相似文献
5.
同济医科大学控烟活动及效果评价 总被引:1,自引:0,他引:1
我校自1993年开展控烟工作,1995年9月开始创办无吸烟大学校园,采取了卫生宣教和行政干预等综合措施,并进行了效果评价。高强度干预措施实施前期(1995年3月)和中期(1996年10月)相比,男医学生和男女学生平均吸烟率分别从16.3%和11.4%下降到9.6%和5.94%;男教工和男女教工平均吸烟率分别从28.6%和13.8%下降到13.9%和8.86%。 相似文献
6.
米利酮是非洋地黄,非儿茶酚胺类强心药,具有明显的正性肌力和扩血管作用。国外用于治疗难治性心衰及洋地黄中毒的心衰病人。本文用豚鼠乳头肌及主动脉条进行实验,结果表明合成与进口米利酮的正性肌力作用效价相同,对抗去甲肾上腺素缩血管的作用也等同。 相似文献
7.
The peptide Leu-Asp-Asp-Ser-Lys-Arg-Val-Ala-Lys-Arg-Lys-Leu-Ile-Glu, which corresponds to sequence 124 to 137 of c-erb-A protein, was synthesized and tested as substrate for protein kinase C (PKC). Although a typical recognition sequence for PKC, consisting of a cluster of basic residues, is found on the C-terminus side of serine, its phosphorylation was totally prevented by the presence of the two acidic residues on the amino-terminus side. Three analogs in which aspartyl residues were successively replaced with alanine were studied and the influence of the acidic side chain in modulating phosphorylation by PKC was thus possible to determine. The results show that the presence of a single aspartyl residue located in positions i-1 or i-2 with respect to the phosphorylable residue can almost totally abolish the positive effect of a highly favorable cluster of basic residues. These observations highlight the role of negative substrate specificity determinants in settling the protein substrate profile of protein kinase C. 相似文献
8.
单丝聚丙烯合成非吸收齿状线在美容整形应用中并发症的防治及应用改进 总被引:2,自引:0,他引:2
目的探讨单丝聚丙烯合成非吸收齿状线在美容整形中的并发症产生的原因及应用方法及技术的改进。方法对近两年的单丝聚丙烯合成非吸收齿状线在美容整形中的应用进行总结与分析。结果改进应用方法后,并发症明显减少,效果加强。结论单丝聚丙烯合成非吸收齿状线在美容整形中应用得当,可减少并发症、取得显著效果。 相似文献
9.
G. B. Gurrola R. Molinar-Rode M. Sitges A. Bayon L. D. Possani 《Journal of neural transmission (Vienna, Austria : 1996)》1989,75(1):11-20
Summary A nonapeptide Thr-Ile-Ile-Asn-Val-Lys-Cys-Thr-Ser (NTX1–9) and a decapeptide Met-Asn-Gly-Lys-Cys-Lys-Cys-Tyr-Asn-Asn (NTX30–39) corresponding to the N-terminal and C-terminal sequences respectively of Noxiustoxin (NTX) were synthesized by the solid phase method of Merrifield (1963). The first synthetic peptide (NTX1–9) was shown to be toxic to mice independently of the route of administration: intraperitoneally, subcutaneously or intraventricularly (100–200 g/20 g mouse weight). The second (NTX30–39) was not toxic even at higher dose (400 g/20 g mouse). When the effects of the peptide NTX1–9 and of the authentic toxin (Noxiustoxin) were studied on the liberation of [3H] 4-aminobutyric acid (3H-GABA) from mouse synaptosomes, both gave essentially the same results, except that peptide NTX1–9 was needed at higher concentration. Synthetic peptide NTX30–39 had no effect in the same preparation at even higher doses. The GABA release produced by toxic peptide NTX1–9 was not affected by tetrodotoxin but was completely abolished by the presence of the K+ ionophore valinomycin, mimicking the effect of native NTX in the same system (Sitges et al., 1986). These results indicate that the toxic active site of Noxiustoxin is possibly located in or near the N-terminal amino acid portion of the molecule.Abbreviations used BOC
amino acids ter-butyloxycarbonyl-amino acids
- BOC
amino acid-PAM-resin ter-butyloxycarbonyl-aminoacyl-4-(oxymethyl)-phenacetamidomethyl-resin
- GABA 4
aminobutyric acid
- HPLC
high performance liquid chromatography
- MSA
mouse serum albumin
- NTX
Noxiustoxin
- NTX
(numbers) synthetic peptides with amino acid sequences of NTX at position start (first number) to position end (second number) of the sequence according to Fig. 1
- TTX
tetrodotoxin
Supported in part by the Mexican Council of Science and Technology (CONACyT), grants PVT/QF/NAL/84/2182, PVT/AI/NAL/85/3029 to L.D.P.; PCSACNA 022640 to A.B. A patent request claiming rights on the use of synthetic NTX and related peptides was presented in Washington, DC (U.S.A.), Serial number 07/132,169, filing date December 14, 1987. 相似文献
10.
Elisa Moya-Sáez Rafael Navarro-González Santiago Cepeda Ángel Pérez-Núñez Rodrigo de Luis-García Santiago Aja-Fernández Carlos Alberola-López 《NMR in biomedicine》2022,35(9):e4754
Glioblastoma is an aggressive and fast-growing brain tumor with poor prognosis. Predicting the expected survival of patients with glioblastoma is a key task for efficient treatment and surgery planning. Survival predictions could be enhanced by means of a radiomic system. However, these systems demand high numbers of multicontrast images, the acquisitions of which are time consuming, giving rise to patient discomfort and low healthcare system efficiency. Synthetic MRI could favor deployment of radiomic systems in the clinic by allowing practitioners not only to reduce acquisition time, but also to retrospectively complete databases or to replace artifacted images. In this work we analyze the replacement of an actually acquired MR weighted image by a synthesized version to predict survival of glioblastoma patients with a radiomic system. Each synthesized version was realistically generated from two acquired images with a deep learning synthetic MRI approach based on a convolutional neural network. Specifically, two weighted images were considered for the replacement one at a time, a T2w and a FLAIR, which were synthesized from the pairs T1w and FLAIR, and T1w and T2w, respectively. Furthermore, a radiomic system for survival prediction, which can classify patients into two groups (survival >480 days and 480 days), was built. Results show that the radiomic system fed with the synthesized image achieves similar performance compared with using the acquired one, and better performance than a model that does not include this image. Hence, our results confirm that synthetic MRI does add to glioblastoma survival prediction within a radiomics-based approach. 相似文献