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Timothy D. Lyon Igor Frank Matthew K. Tollefson Robert F. Tarrell Paras H. Shah Robert H. Thompson Robert J. Karnes Stephen A. Boorjian 《Urologic oncology》2021,39(6):370.e1-370.e8
IntroductionIntraoperative hypothermia (IOH) has been suggested to adversely impact outcomes following surgery. The objective of this study was to evaluate the association between IOH and survival following radical cystectomy (RC).MethodsPatients who underwent RC for bladder cancer from 2003 to 2018 were identified in our cystectomy registry. Intraoperative temperatures were extracted from the anesthesia record. IOH was defined as a median intraoperative temperature <36°C, and severe IOH as ≤ 35°C. Time under 36°C was assessed as a continuous variable. Recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were estimated using the Kaplan-Meier method. Associations between IOH and outcomes were assessed with multivariable Cox proportional hazards models.ResultsA total of 852 patients were identified, among whom 274 (32%) had IOH. Median follow up among survivors was 4.9 years (IQR 2.4–8.7), during which time 483 patients died, including 343 from bladder cancer. Two-year survival was not significantly different between patients with and without IOH (CSS: 74% vs. 71%, P= 0.31; OS: 68% vs. 67%, P= 0.13). Following multivariable adjustment, neither IOH nor time under 36°C was significantly associated with survival. A total of 37 patients (4.3%) had severe IOH. These patients were observed to have significantly lower 2-year OS (56% vs. 68%, P= 0.005); however, this association did not remain statistically significant after multivariable adjustment (P= 0.92).ConclusionIOH was not independently associated with survival following RC. These data do not support IOH as a prognostic factor for cancer outcomes among patients undergoing RC. 相似文献
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James D. Weinrich Ph.D. Peter J. Snyder Ph.D. Richard C. Pillard M.D. Igor Grant M.D. Denise L. Jacobson M.P.H. S. Renée Robinson R.N. M.A. M.F.C.C. J. Allen McCutchan M.D. 《Archives of sexual behavior》1993,22(2):157-168
Many researchers interested in sexual orientation can be separated into two camps: The lumpers, who try to reduce sexual classifications to as small a number of categories as possible, and the splitters, who try to show differences among groups and individuals that make classification schemes increasingly difficult and/or intricate. We report factor analyses of the Klein Grid (a questionnaire with 21 sexual orientation items) to see how many factors emerge in two samples of strikingly different origins. In both samples, the first factor to emerge loaded substantially on all of the Klein Grid's 21 items. This factor accounted for a majority of the variance. In both samples, a second, correlated factor emerged which indexed a separation between most of the items and those having to do with social and/or emotional preferences. In both samples, a third correlated factor also emerged, but this factor differed between the two populations: one refined the social/emotional distinction and the other distinguished ideal behavior from past and current behavior. We conclude on the basis of our analysis that both the lumpers and the splitters are correct.Supported by NIMH grants IP50 MH 45294 and R01 MH 43298. 相似文献
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Kenneth V. Honn Dean G. Tang Xiang Gao Igor A. Butovich Bin Liu Jozsef Timar Wolfgang Hagmann 《Cancer metastasis reviews》1994,13(3-4):365-396
Arachidonic acid metabolites have been implicated in multiple steps of carcinogenesis. Their role in tumor cell metastasis, the ultimate challenge for the treatment of cancer patients, are however not well-documented. Arachidonic acid is primarily metabolized through three pathways, i.e., cyclooxygenase, lipoxygenase, and P450-dependent monooxygenase. In this review we focus our attention on one specific lipoxygenase, i.e., 12-lipoxygenase, and its potential role in modulating the metastatic process. In mammalian cells there exist three types of 12-lipoxygenases which differ in tissue distribution, preferential substrates, and profile of their metabolites. Most of these 12-lipoxygenases have been cloned and sequenced, and the molecular and biochemical determinants responsible for catalysis of specific substrates characterized. Solid tumor cells express 12-lipoxygenase mRNA, possess 12-lipoxygenase protein, and biosynthesize 12(S)-HETE [12(S)-hydroxyeicosatetraenoic acid], as revealed by numerous experimental approaches. The ability of tumor cells to generate 12(S)-HETE is positively correlated to their metastatic potential. A large collection of experimental data suggest that 12(S)-HETE is a crucial intracellular signaling molecule that activates protein kinase C and mediates the biological functions of many growth factors and cytokines such as bFGF, PDGF, EGF, and AMF. 12(S)-HETE plays a pivotal role in multiple steps of the metastatic cascade encompassing tumor cell-vasculature interactions, tumor cell motility, proteolysis, invasion, and angiogenesis. The fact that 12-lipoxygenase is expressed in a wide diversity of tumor cell lines and 12(S)-HETE is a key modulatory molecule in metastasis provides the rationale for targeting these molecules in anti-cancer and anti-metastasis therapeutic protocols. 相似文献
48.
Porous Polyethylene Implants for Nasal Reconstruction: Clinical and Histologic Studies 总被引:2,自引:0,他引:2
Niechajev I 《Aesthetic plastic surgery》1999,23(6):395-402
This paper describes a technique of using Medpor porous high-density polyethylene implants for nasal reconstruction and chin
augmentation. This biocompatible material has been used successfully during the last decade for various applications in the
reconstruction of the facial skeleton. Among its most frequent uses are repair of the orbital floor and reconstruction of
the burned ear, which became standard methods at many centers. Relatively little experience is, at present, on hand concerning
the use of porous polyethylene in reconstruction of the nasal framework. Twenty-three consecutive, difficult nasal reconstructions
were performed using this method since 1996. Patients were followed up for from 1 to 3 years (mean, 2 years). The results
were durable and stable over the time. Eight patients had saddle nose deformity and 15 had catastrophe noses, mostly referrals,
previously operated on from one to four times. My aesthetic goals were correction of the depressed nasal dorsum, creation
of an acceptable nasal dorsum in the thick and/or twisted noses, and tip elevation. For nasal applications Medpor is available
as a strut or sheet. Its body, once implanted, becomes rapidly vascularized and both soft tissue ingrowth and collagen deposition
occur. This was confirmed by the microscopic investigation of biopsies. One patient of Vietnamese origin had an aesthetically
pleasing result, but her family refused to accept her westernized nose. This gave me a unique opportunity to study the whole
Medpor implant 6 months after implantation. There were two complications, one small implant exposure and one low-virulent
infection involving the nasal tip. Following revision and antibiotic treatment, both patients healed without sequel. All reconstructions
were successful in restoring nasal aesthetics and function. Four patients underwent chin augmentations with an uneventful
clinical course. 相似文献
49.
Marcelo M Rossa Thomaz A A Rocha-e-Silva Cristina H B Terruggi Antonio C Tedesco Heloisa S Selistre-de-Araujo Iouri E Borissevich Igor A Degterev 《Pharmacological research》2003,48(4):369-375
The cytotoxicity of two nitroheterocyclic compounds (NHCD), Nitracrine, 1-nitro-9(3'3'-dimethylaminopropylamino) acridine (Polfa, Poland) and Quinifuryl, 2-(5'-nitro-2'-furanyl) ethenyl-4-[N-[4-(N,N-diethylamino)-1'-methylbutyl] carbamoyl] quinoline (Dr. N. M. Sukhova, Institute of Organic Synthesis, Riga, Latvian Republic), towards two lines of leukaemic cells and a line of non-transformed cells, was determined under normoxia conditions. Although both drugs showed significant cytotoxicity to all cell lines (LC(50) for 24h, < or = 2 microM) with that of Nitracrine exceeding Quinifuryl, their toxicity towards murine leukaemia P388 was substantially higher, compared to murine fibroblasts NIH3T3. In addition, the rate of cell death was also two- to three-fold higher in case of P388 cells versus NIH3T3. Interestingly, human erythroleukaemia K562 cells were shown to uptake the drugs 10 min after their addition to the tissue culture medium, while the LC(50) values were reached after a substantial delay of 3h. This delay might be due to the intracellular transformation of drugs required for cell killing. 相似文献
50.
Grazyna Faure Alenka Copic Sabine Le Porrier Franc Gubensek Cassian Bon Igor Krizaj 《Toxicon》2003,41(4):509-517
Crotoxin, a potent neurotoxin from the South American rattlesnake Crotalus durissus terrificus, is a heterodimeric phospholipase A(2) (EC 3.1.1.4), which blocks the release of acetylcholine from peripheral neurons. We previously have suggested the existence of a 48 kDa crotoxin-binding protein in the presynaptic membranes of the electric organ of Torpedo marmorata. Here, we report the purification and characterization of this protein that we called the crotoxin acceptor protein from Torpedo (CAPT). The membranes of electric organs from Torpedo were solubilized with a detergent (4% (w/v) Triton X-100) and CAPT was isolated by affinity chromatography on a crotoxin column. SDS-PAGE showed that the purified protein was homogeneous and cross-linking studies with radioiodinated crotoxin confirmed that it had retained its toxin-binding properties. The purified CAPT has similar molecular mass as crocalbin, a crotoxin-binding protein isolated from porcine brains, yet anti-crocalbin antiserum failed to recognize CAPT. Surface plasmon resonance biosensor technology was used to measure the specific interaction between crotoxin and solubilized CAPT. Using this method, it was possible to follow CAPT throughout the purification procedure. As well, an apparent dissociation constant (K(d)(app)) of 3.4 nM was calculated for the interaction of pure CAPT and crotoxin from the dissociation rate constant (k(off)=1.2 x 10(-2)s(-1)) and the association rate constant (k(on)=3.5 x 10(6)M(-1)s(-1)). 相似文献