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排序方式: 共有1639条查询结果,搜索用时 15 毫秒
61.
Xue Wang Mariet Allen
zkan Joseph S. Reddy Frederick Q. Tutor-New Monica Castanedes Casey Minerva M. Carrasquillo Stephanie R. Oatman Yuhao Min Yan W. Asmann Cory Funk Thuy Nguyen Charlotte C.G. Ho Kimberly G. Malphrus Nicholas T. Seyfried Allan I. Levey Steven G. Younkin Melissa E. Murray Dennis W. Dickson Nathan D. Price Todd E. Golde Nilüfer Ertekin-Taner 《The Journal of clinical investigation》2022,132(2)
62.
63.
Efficient gene delivery to multipotential hematopoietic stem cells would greatly facilitate the development of effective gene therapy for certain hematopoietic disorders. We have recently described a rapid multiparameter sorting procedure for significantly enriching stem cells with competitive long-term lymphomyeloid repopulating ability (CRU) from 5-fluorouracil (5-FU)-treated mouse bone marrow. The sorted cells have now been tested as targets for retrovirus-mediated delivery of a marker gene, NeoR. They were cocultured for 4 days with fibroblasts producing a high titer of retrovirus in medium containing combinations of the hematopoietic growth factors interleukin-3 (IL-3), IL-6, c-kit ligand (KL), and leukemia inhibitory factor (LIF) and then injected into lethally irradiated recipients, together with sufficient "compromised" bone marrow cells to provide short-term support. Over 80% of the transplanted mice displayed high levels (> or = 20%) of donor- derived leukocytes when analyzed 4 to 6 months later. Proviral DNA was detected in 87% of these animals and, in half of them, the majority of the hematopoietic cells were marked. Thus, infection of the stem cells was most effective. The tissue and cellular distribution of greater than 100 unique clones in 55 mice showed that most sorted stem cells had lymphoid as well as myeloid repopulating potential. Secondary transplantation provided strong evidence for infection of very primitive stem cells because, in several instances, different secondary recipients displayed in their marrow, spleen, thymus and day 14 spleen colony-forming cells the same proviral integration pattern as the primary recipient. Neither primary engraftment nor marking efficiency varied for stem cells cultured in IL-3 + IL-6, IL-3 + IL-6 + KL, IL-3 + IL-6 + LIF, or all four factors, but those cultured in IL-3 + IL-6 + LIF appeared to have lower secondary engraftment potential. Provirus expression was detected in 72% of the strongly marked mice, albeit often at low levels. Highly efficient retroviral marking of purified lymphomyeloid repopulating stem cells should enhance studies of stem cell biology and facilitate analysis of genes controlling hematopoietic differentiation and transformation. 相似文献
64.
65.
Michael D. Eggen PhD Michael G. Bateman MENG Christopher D. Rolfes BA Stephen A. Howard BA Cory M. Swingen PhD Paul A. Iaizzo PhD 《Journal of magnetic resonance imaging : JMRI》2010,31(2):466-469
This study demonstrates the capabilities of MRI in the assessment of cardiac pacing induced ventricular dyssynchrony, and the findings support the need for employing more physiological pacing. A human donor heart deemed non‐viable for transplantation, was reanimated using an MR compatible, four‐chamber working perfusion system. The heart was imaged using a 1.5T MR scanner while being paced from the right ventricular apex (RVA) via an epicardial placed lead. Four‐chamber, short‐axis, and tagged short‐axis cines were acquired in order to track wall motion and intramyocardial strain during pacing. The results of this study revealed that the activation patterns of the left ventricle (LV) during RVA pacing demonstrated intraventricular dyssynchrony; as the left ventricular mechanical activation proceeded from the septum and anterior wall to the lateral wall, with the posterior wall being activated last. As such, the time difference to peak contraction between the septum and lateral wall was ~125 msec. Likewise, interventricular dyssynchrony was demonstrated from the four‐chamber cine as the time difference between the peak LV and RV free wall motion was 180 msec. With the ongoing development of MR safe and MR compatible pacing systems, we can expect MRI to be added to the list of imaging modalities used to optimize cardiac resynchronization therapy (CRT) and/or alternate site pacing. J. Magn. Reson. Imaging 2010; 31: 466–469. © 2010 Wiley‐Liss, Inc. 相似文献
66.
Seale GS Caroselli JS High WM Becker CL Neese LE Scheibel R 《Brain injury : [BI]》2002,16(11):955-967
Objective : Evaluate changes in community integration for survivors of traumatic brain injury (TBI) who participated in a post-acute rehabilitation programme.
Design : Cohort, prospective study investigating change from admission to post-discharge.
Participants : Individuals, the majority of whom were diagnosed with severe TBI, were placed into one of two groups as follows: (1) admitted for treatment less than 1 year post-injury (L1Y) or (2) admitted for treatment between 1-5 years post-injury (G1Y).
Measure : The Community Integration Questionnaire (CIQ).
Results : Both groups showed significant improvements from admission to follow-up; however, some CIQ findings were more pronounced for the L1Y group. Reliable change (RC) methodology was used to assess individual change. Results of this approach were consistent with group results, but tempered the perception of degree of change.
Conclusions : Findings cannot simply be attributed to neurological recovery and individual factors are important to examine when assessing change. 相似文献
Design : Cohort, prospective study investigating change from admission to post-discharge.
Participants : Individuals, the majority of whom were diagnosed with severe TBI, were placed into one of two groups as follows: (1) admitted for treatment less than 1 year post-injury (L1Y) or (2) admitted for treatment between 1-5 years post-injury (G1Y).
Measure : The Community Integration Questionnaire (CIQ).
Results : Both groups showed significant improvements from admission to follow-up; however, some CIQ findings were more pronounced for the L1Y group. Reliable change (RC) methodology was used to assess individual change. Results of this approach were consistent with group results, but tempered the perception of degree of change.
Conclusions : Findings cannot simply be attributed to neurological recovery and individual factors are important to examine when assessing change. 相似文献
67.
Tucker CM Fennell RS Pedersen T Higley BP Wallack CE Peterson S 《Pediatric nephrology (Berlin, Germany)》2002,17(4):251-256
This study examined perceived medication regimen characteristics as factors in levels of medication adherence among 26 African
American and 42 European American pediatric renal transplant patients. Among both groups, perceived characteristics of their
medication regimen, including pill size, pill taste and medication complexity, were found to have significantly low to moderate
associations with medication adherence. These associations were stronger and more consistent across medication adherence measures
among the African American patients. This supports the need to separately examine the factors contributing to medication adherence
among ethnically different pediatric patients. Suggestions for promoting medication adherence among pediatric patients with
renal transplants and implications for future research are discussed.
Received: 21 September 2000 / Revised: 14 November 2001 / Accepted: 18 November 2001 相似文献
68.
Mouse leukemia L1210 cells selected for resistance to drugs targeted specifically at each of the protein subunits of ribonucleotide reductase were studied for their ability to grow in vivo. The life-span of the mice injected with hydroxyurea-resistant L1210 cells, which have elevated levels of the mRNA and protein for the non-heme iron (NHI, R2) subunit of ribonucleotide reductase, was approximately twice that of the mice injected with equal numbers of the parental wild-type L1210 leukemia cells. The life-span of mice injected with the L1210 cells that had alterations in the effector-binding subunit (EB, R1) was considerably shorter than the mice injected with the parental wild-type L1210 cells. These results provide direct evidence that tumor cells with alterations in the properties of ribonucleotide reductase grow differently in vivo, with defined effects on the host mouse that cause either an increased survival time or a decreased survival time compared to the effects of wild-type L1210 leukemia cells on tumor-bearing mice. 相似文献
69.
Stimulation of Ca(2+) influx through ATP receptors on rat brain synaptosomes: identification of functional P2X(7) receptor subtypes 下载免费PDF全文
Lundy PM Hamilton MG Mi L Gong W Vair C Sawyer TW Frew R 《British journal of pharmacology》2002,135(7):1616-1626
1. ATP receptors of the P2X class have previously been identified on autonomic nerve endings and on a limited population of CNS neurons. 2. In the present study P2X receptors on mammalian cortical synaptosomes have been identified by a variety of functional and biochemical studies. In choline buffer ATP analogues caused concentration/time dependent Ca(2+) influx. Relative to the effects caused by ATP, benzoylbenzoyl ATP (BzATP) was about seven times more active than ATP while 2-me-S-ATP and ATPgammaS were much less active. alpha,beta-me- ATP and beta,gamma-me-ATP were virtually inactive. In sucrose buffer, relative to choline buffer, the activity of BzATP was more than doubled while activity in sodium buffer was reduced. Moreover, the P2X antagonists PPADS or Brilliant Blue G both significantly attenuated influx. These observations suggest the presence of P2X receptors on synaptosomes which subserve Ca(2+) influx. This activity profile of the ATP analogues and the response to blocking agents are characteristic of responses of P2X(7) receptors. 3. Influx was unaffected by the VSCC inhibitors omega-CTx-MVIIC and (-) 202 - 791, indicating that ATP induced Ca(2+) influx occurred primarily through P2X receptors. 4. P2X(7) receptor protein was identified by Western blotting and immunohistochemical staining. Purified preparations were devoid of significant concentrations of GFAP or the microglial marker OX-42 but contained greatly enriched amounts of syntaxin and SNAP 25. 5. The various pharmacological and biochemical studies were all consistent with the presence of functional P2X(7) receptors. 相似文献
70.
9-Nitrocamptothecin (9-NC) dilauroylphosphatidylcholine (DLPC) liposome aerosol was evaluated for potential toxicity in an 8-wk, subacute toxicity study in dogs. Fourteen adult dogs were divided into 2 groups with 10 animals in the 9-NC-DLPC treatment group and 4 animals in the DLPC-only vehicle control group. 9-NC-DLPC was administered to the animals using an Aerotech II nebulizer flowing at 10 L/min. Full-face exposures for 60 min were conducted for 5 consecutive days a week for 8 wk. The estimated deposited aerosol dose was 24.7 microg/kg/day. Animals in the vehicle control group received aerosolized DLPC only. Body weight, food consumption, urinalysis, in-life observations, hematology, plasma chemistry, and necropsy and histopathology were monitored before and during the treatment period and in a subset of animals for 2 wk following the end of treatment. Animals were observed for signs of pharmacologic and/or toxicologic effects three times on days of dosing and once daily on nondosing days. 9-NC-DLPC liposomes administered as a small-particle aerosol were determined to be nontoxic to dogs when given for 5 days/wk, for a duration of 8 wk. DLPC-only liposome also had no toxic effects. 相似文献