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101.
Corzo D; Yunis JJ; Salazar M; Lieberman JA; Howard A; Awdeh Z; Alper CA; Yunis EJ 《Blood》1995,86(10):3835-3840
Genes of the major histocompatibility complex (MHC) have been associated with susceptibility to drug-induced adverse reactions. We previously found that clozapine-induced agranulocytosis (CA) is associated with the HLA-DRB1*0402, DRB4*0101, DQB1*0302, DQA1*0301 haplotype in Ashkenazi Jewish patients and with the HLA-DRB1*1601, DRB5*02, DQB1*0502, DQA1*0102 haplotype in non-Jewish patients. In the present study, we tested the hypothesis that the variants of the heat- shock protein 70 (HSP-70) encoded by the HSP-70 loci located within the MHC region and known to be involved in apoptosis and regulation of cell proliferation could play an important role in molecular mechanisms of CA. First, we analyzed HSP70-2 polymorphism in risk-associated haplotypes from HLA homozygous cells and normal individuals and confirmed that the HSP70-2 9-kb variant was associated invariably with DR4 (HLA-DRB1*0402, DQB1*0302) and DR2 (HLA-DRB1*01601, DQB1*0502, DQA1*0102 and HLA-DRB1*1501, DQB1*0602) haplotypes, which were the haplotypes found increased in Jewish and non-Jewish patients with CA, respectively. The 9.0-kb variant was also found to be associated with HLA-B44, DRB1*0401 and HLA-B44, DRB1*07 haplotypes. Second, in patients with CA (12 Ashkenazi Jewish and 20 non-Jewish patients), HSP70-1 A and HSP70-2 9.0-kb variants were associated with the MHC haplotypes found by us to be markers of susceptibility to CA. The clozapine-treated control group had an excess number of HSP70-1 C and HSP70-2 8.5-kb variants, consistent with genetic resistance to CA associated with those variants. This finding supports our hypothesis that a dominant gene within the MHC region (marked by HSP70-1 and HSP70-2), but not necessarily HLA, is associated with CA in two different ethnic groups. 相似文献
102.
Michael R. Sawaya Duilio Cascio Mari Gingery Jose Rodriguez Lukasz Goldschmidt Jacques-Philippe Colletier Marc M. Messerschmidt Sébastien Boutet Jason E. Koglin Garth J. Williams Aaron S. Brewster Karol Nass Johan Hattne Sabine Botha R. Bruce Doak Robert L. Shoeman Daniel P. DePonte Hyun-Woo Park Brian A. Federici Nicholas K. Sauter Ilme Schlichting David S. Eisenberg 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(35):12769-12774
It has long been known that toxins produced by Bacillus thuringiensis (Bt) are stored in the bacterial cells in crystalline form. Here we describe the structure determination of the Cry3A toxin found naturally crystallized within Bt cells. When whole Bt cells were streamed into an X-ray free-electron laser beam we found that scattering from other cell components did not obscure diffraction from the crystals. The resolution limits of the best diffraction images collected from cells were the same as from isolated crystals. The integrity of the cells at the moment of diffraction is unclear; however, given the short time (∼5 µs) between exiting the injector to intersecting with the X-ray beam, our result is a 2.9-Å-resolution structure of a crystalline protein as it exists in a living cell. The study suggests that authentic in vivo diffraction studies can produce atomic-level structural information.The advent of X-ray free-electron lasers (XFELs) has made it possible to obtain atomic resolution macromolecular structures from crystals with sizes approximating only 1/60th of the volume of a single red blood cell. Brief, intense pulses of coherent X-rays, focused on a spot of 3-μm diameter, have produced 1.9-Å-resolution diffraction data from a stream of lysozyme crystals, each crystal no bigger than 3 μm3 (1). A stream of crystals, not just one crystal, is required to collect the many tens of thousands of diffraction patterns that compose a complete data set. No single crystal can contribute more than one diffraction pattern because the XFEL beam is so intense and the crystals so small that the crystals are typically vaporized after a single pulse. Impressively, a photosystem I crystal no bigger than 10 unit cells (300 nm) on an edge produced observable subsidiary diffraction peaks between Bragg reflections, details which would be unobservable from conventionally sized crystals (2). With this new ability to collect diffraction patterns from crystals of unprecedentedly small dimensions, it is conceivable that high-resolution diffraction data could be collected from crystals in vivo. The structure obtained in this manner would be unaltered from that occurring naturally in a living cell, free from distortion that might otherwise potentially arise from nonphysiological conditions imposed by recrystallization. A practical advantage would also be gained by eliminating the need for a protein purification step, whether the in vivo grown crystals were naturally, or heterologously expressed (3).The nascent field of serial femtosecond crystallography (SFX) has published results on nine different macromolecular systems since its inception in 2009 (3, 9). The crystals for this study were not grown in artificial crystallization chambers as has been the protocol of conventional macromolecular crystallography since the 1950s. Instead, crystals were grown in cells. Specifically, they were grown in Sf9 insect cells, heterologously expressing Trypanosoma brucei cathepsin B. These in vivo-grown crystals were used for the XFEL diffraction experiment. To this end, the cells were lysed and the crystals were extracted before injecting them in the XFEL beam for data collection. This last purification step seems to be the only major departure from our goal of obtaining high-resolution structural information from crystal inclusions in vivo, without requiring the crystal to be extracted from the cell that assembled it. Here we attempt to go one step further than previous studies—to record diffraction from crystals within living cells.
Open in a separate window*The available XFEL energy was limited to 2 keV (6.2 Å wavelength) when these experiments were conducted.Our target for in vivo crystal structure determination is the insecticidal Cry3A toxin from Bacillus thuringiensis (Bt). The bacterium naturally produces crystals of toxin during sporulation (16). Presumably, the capacity for in vivo crystallization evolved in Bt as a mechanism to store the toxin in a concentrated, space-efficient manner. Since the 1920s, farmers have used the crystalline insecticidal proteins to control insect pests; its production as a natural pesticide is now a commercial enterprise. Attempts to structurally characterize the toxins date back to more than 40 y ago with the first report of diffraction from isolated crystals that were packed together in powder form to obtain a measurable signal; X-ray sources available at the time were relatively weak (17). More than 20 y later, the structure was determined at 2.5-Å resolution by single crystal diffraction using a synchrotron X-ray source (18). However, to achieve this result, the authors dissolved the naturally occurring microcrystals and recrystallized the toxin using the hanging drop vapor diffusion method. To date, more than a dozen Bt toxin structures have been reported from various strains [Protein Data Bank (PDB) ID codes 1cby, 1ciy, 1i5p, 1ji6, 1w99, 2d42, 2c9k, 2rci, 3eb7, 2ztb, 3ron, 4d8m, 4ato, 4ary, and 4arx], but none using naturally occurring crystals, and all of the crystals had lost their native context.In pursuit of in vivo diffraction, we took advantage of the Bt subsp. israelensis strain 4Q7/pPFT3As to produce the largest in vivo crystals achievable. This strain contains the plasmid pPFT3As, which increases expression of Cry3A by 12.7-fold over wild type by using strong promoters and an mRNA stabilizing sequence (19). The level of Cry3A production is such that the cell essentially distorts to take on the shape of the enclosed crystal. The calculated average crystal volume is 0.7 µm3 (19), almost accounting for the volume of the cell. To explore the possibilities for in situ data collection of in vivo microcrystals, we injected both the crystals in cells and crystals that we isolated from cells in the XFEL beam and collected SFX diffraction data. Our experiments revealed that the cell wall and other cellular components are not an obstacle to achieving 2.9-Å-resolution diffraction, and analogous studies in other systems might be similarly successful. 相似文献
Table 1.
SFX publications from XFEL sources to datePublication date | System | Product | Resolution (Å) | Title of publication | Authors | Reference |
Feb 2011* | Photosystem I | Structure | 8.7 | Femtosecond X-ray protein nanocrystallography | Chapman et al. | 2 |
Dec 2011* | Lysozyme | Structure | 8.7 | Radiation damage in protein serial femtosecond crystallography using an X-ray free-electron laser | Lomb et al. | 4 |
Jan 2012* | Photosystem I-Ferredoxin | Data | 11 | Time-resolved protein nanocrystallography using an X-ray free-electron laser | Aquila et al. | 5 |
Jan 2012* | Cathepsin B | Data | 7.5 | In vivo protein crystallization opens new routes in structural biology | Koopman et al. | 3 |
Jan 2012* | Photosynthetic Reaction Center | Structure | 7.4 | Lipidic phase membrane protein serial femtosecond crystallography | Johansson et al. | 6 |
Jun 2012 | Photosystem II | Structure | 6.6 | Room temperature femtosecond X-ray diffraction of photosystem II microcrystals | Kern et al. | 7 |
Jul 2012 | Lysozyme | Structure | 1.9 | High-resolution protein structure determination by serial femtosecond crystallography | Boutet et al. | 1 |
Nov 2012 | Thermolysin | Data | 4.0 | Nanoflow electrospinning serial femtosecond crystallography | Sierra et al. | 8 |
Jan 2013 | Cathepsin B | Structure | 2.1 | Natively inhibited Trypsanosoma brucei cathepsin B structure determined by using an X-ray laser | Redecke et al. | 9 |
Apr 2013 | Photosystem II | Structure | 5.7 | Simultaneous femtosecond X-ray spectroscopy and diffraction of photosystem II at room temperature | Kern et al. | 10 |
May 2013 | Lysozyme | Structure | 3.2 | Anomalous signal from S atoms in protein crystallographic data from an X-ray free-electron laser | Barends et al. | 11 |
Sept 2013 | Ribosome | Data | <6 | Serial femtosecond X-ray diffraction of 30S ribosomal subunit microcrystals in liquid suspension at ambient temperature using an X-ray free-electron laser | Demirci et al. | 12 |
Dec 2013 | Photosynthetic Reaction Center | Structure | 3.5 | Structure of a photosynthetic reaction center determined by serial femtosecond crystallography | Johansson et al. | 13 |
Dec 2013 | Serotonin receptor | Structure | 2.8 | Serial femtosecond crystallography of G protein-coupled receptors | Liu et al. | 14 |
Jan 2014 | Lysozyme + Gd | Structure | 2.1 | De novo protein crystal structure determination from XFEL data | Barends et al. | 15 |
This study | Cry3A toxin, isolated crystals and whole cells | Structure | 2.8, 2.9 | 2.9 Å-Resolution protein crystal structure obtained from injecting bacterial cells into an X-ray free-electron laser beam | Sawaya et al. | This study |
103.
Cilostazol is a generic drug with antiplatelet and antiproliferative effects. It is unclear whether adding cilostazol to standard dual antiplatelet therapy (aspirin and clopidogrel) after percutaneous coronary intervention reduces restenosis and improves the outcomes. We, therefore, conducted a systematic review and meta-analysis. We systematically searched the Cochrane Library, EMBASE, and MEDLINE databases for randomized controlled trials comparing dual antiplatelet therapy with and without cilostazol after percutaneous coronary intervention. The data were pooled using random-effects models and stratified into short-term (1-month), midterm (1- to 12-month), and long-term (≥12-month) follow-up durations. Twelve randomized controlled trials involving 5,655 patients met our inclusion criteria. The addition of cilostazol to dual antiplatelet therapy was not associated with a significant change in target lesion revascularization (TLR) and target vessel revascularization (TVR) at short-term follow-up. However, TLR and TVR were significantly reduced at midterm follow-up (relative risk 0.57, 95% confidence interval 0.39 to 0.84, and relative risk 0.62, 95% confidence interval 0.47 to 0.83, respectively). Data regarding TLR and TVR at long-term follow-up were limited and inconclusive. We did not find a difference in myocardial infarction, mortality, or major bleeding at any follow-up duration. In conclusion, the addition of cilostazol to dual antiplatelet therapy after percutaneous coronary intervention has favorable effects on TLR and TVR at 1 to 12 months, with no differences in adverse outcomes at any follow-up duration. 相似文献
104.
Tahiri M Mottillo S Joseph L Pilote L Eisenberg MJ 《The American journal of medicine》2012,125(6):576-584
BackgroundAcupuncture, hypnotherapy, and aversive smoking are the most frequently studied alternative smoking cessation aids. These aids are often used as alternatives to pharmacotherapies for smoking cessation; however, their efficacy is unclear.MethodsWe carried out a random effect meta-analysis of randomized controlled trials to determine the efficacy of alternative smoking cessation aids. We systematically searched the Cochrane Library, EMBASE, Medline, and PsycINFO databases through December 2010. We only included trials that reported cessation outcomes as point prevalence or continuous abstinence at 6 or 12 months.ResultsFourteen trials were identified; 6 investigated acupuncture (823 patients); 4 investigated hypnotherapy (273 patients); and 4 investigated aversive smoking (99 patients). The estimated mean treatment effects were acupuncture (odds ratio [OR], 3.53; 95% confidence interval [CI], 1.03-12.07), hypnotherapy (OR, 4.55; 95% CI, 0.98-21.01), and aversive smoking (OR, 4.26; 95% CI, 1.26-14.38).ConclusionOur results suggest that acupuncture and hypnotherapy may help smokers quit. Aversive smoking also may help smokers quit; however, there are no recent trials investigating this intervention. More evidence is needed to determine whether alternative interventions are as efficacious as pharmacotherapies. 相似文献
105.
106.
107.
Dan Eisenberg Anna Bellatorre Nina Bellatorre 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2013,17(1):63-67
Background:
The laparoscopic sleeve gastrectomy (LSG) is emerging as an effective bariatric operation and is especially attractive in high-risk populations. In this study we examine the efficacy of LSG as a stand-alone operation in the veteran population.Methods:
This is a retrospective review of consecutive patients who underwent LSG as a stand-alone procedure at the Palo Alto Veterans Affairs medical center with a minimum 12-month follow-up.Results:
Of 205 patients undergoing bariatric surgery, 71 patients had a sleeve gastrectomy, 40 of whom had the operation performed at least 12 months previously. Thirty-six (90%) were available for 1-year follow-up, with a mean follow-up duration of 22 months (range: 12–42), a mean body mass index of 48.3 kg/m2, and an 83% male population. Mean percent excess weight loss was 61% at an average of 22 months, with no significant difference between severely obese, morbidly obese, and super obese cohorts. Diabetes remission was seen in 56% of patients, hypertension remission in 51.6%, and obstructive sleep apnea remission in 46.4%, and gastroesophageal reflux disease improved or did not change in 83%. Medication use significantly decreased after surgery.Conclusion:
LSG is safe and effective as a stand-alone bariatric operation in the high-risk veteran population. It is effective in severely obese, morbidly obese, and super obese patients. LSG induces remission or improvement in comorbidities of nearly all patients, translating to a decrease in medication use. 相似文献108.
Xinmin Zhang Qiang Hua Chen Peter Farmer Mansoor Nasim Alexis Demopoulos Craig Devoe Tulika Ranjan Mark B. Eisenberg Michael Schulder Chengpeng Bi Jian Yi Li 《Journal of clinical neuroscience》2013,20(1):75-79
Of the 74 immunocompetent patients diagnosed between July 2004 and June 2011 at the North Shore University Hospital and Long Island Jewish Medical Center with primary central nervous system lymphoma, 71 (95.9%) had diffuse large B-cell lymphomas (DLBCL). The median patient age was 68 years (range: 19–87 years) with a slight male preponderance (1.1:1). The overall median survival time was 21 months. For patients older than 70 years, the median survival time was 8 months while for those 70 years or younger, the median survival time was 27 months (p < 0.01). Female patients had a worse prognosis than male patients (p < 0.05, median survival time, 17 months compared to 23 months). We had enough data from 52 of these 71 patients to define the lymphomas as either germinal center B-cell-like (GCB) or activated B-cell-like (ABC) DLBCL. Of these 52 patients, 42 (80.8%) had ABC DLBCL while only 10 (19.2%) had GCB DLBCL. The patients in the GCB subgroup seemed to survive longer than the patients in the ABC subgroup, although the difference did not reach statistical significance. No statistically significant difference in overall survival was seen between patients with BCL-6 positive or negative DLBCL; or between patients with BCL-2 positive or negative DLBCL. 相似文献
109.
Hannah M. Borowsky Marla E. Eisenberg Michaela M. Bucchianeri Niva Piran Dianne Neumark-Sztainer 《Eating disorders》2013,21(4):297-311
ABSTRACTUsing data from a community-based sample (Project EAT-III), this study (N = 1241; mean age = 25.2) examined the relationship of feminist identity with body image and disordered eating. Feminist-identified women reported significantly higher body satisfaction than non-feminist women and women who did not identify as feminists but held feminist beliefs. However, feminist-identified women did not differ from non-feminist women in disordered eating. Women holding feminist beliefs and non-feminist women did not differ in body satisfaction. Our findings suggest that self-identification as a feminist may promote positive body image in young adult women, but may be insufficient to change behaviors. 相似文献
110.