全文获取类型
收费全文 | 1663篇 |
免费 | 253篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 58篇 |
妇产科学 | 37篇 |
基础医学 | 91篇 |
口腔科学 | 73篇 |
临床医学 | 270篇 |
内科学 | 433篇 |
皮肤病学 | 42篇 |
神经病学 | 60篇 |
特种医学 | 298篇 |
外科学 | 133篇 |
综合类 | 18篇 |
预防医学 | 287篇 |
眼科学 | 12篇 |
药学 | 31篇 |
肿瘤学 | 84篇 |
出版年
2024年 | 3篇 |
2023年 | 53篇 |
2022年 | 16篇 |
2021年 | 12篇 |
2020年 | 40篇 |
2019年 | 18篇 |
2018年 | 52篇 |
2017年 | 33篇 |
2016年 | 45篇 |
2015年 | 54篇 |
2014年 | 95篇 |
2013年 | 118篇 |
2012年 | 34篇 |
2011年 | 49篇 |
2010年 | 63篇 |
2009年 | 81篇 |
2008年 | 48篇 |
2007年 | 73篇 |
2006年 | 51篇 |
2005年 | 43篇 |
2004年 | 40篇 |
2003年 | 17篇 |
2002年 | 17篇 |
2001年 | 27篇 |
2000年 | 22篇 |
1999年 | 28篇 |
1998年 | 66篇 |
1997年 | 89篇 |
1996年 | 79篇 |
1995年 | 57篇 |
1994年 | 63篇 |
1993年 | 52篇 |
1992年 | 16篇 |
1991年 | 15篇 |
1990年 | 33篇 |
1989年 | 43篇 |
1988年 | 33篇 |
1987年 | 36篇 |
1986年 | 34篇 |
1985年 | 32篇 |
1984年 | 16篇 |
1983年 | 13篇 |
1982年 | 24篇 |
1981年 | 30篇 |
1980年 | 17篇 |
1979年 | 8篇 |
1978年 | 5篇 |
1977年 | 15篇 |
1976年 | 14篇 |
1975年 | 10篇 |
排序方式: 共有1937条查询结果,搜索用时 15 毫秒
91.
Detection of the chromosomal translocation t(11;14) by polymerase chain reaction in mantle cell lymphomas 总被引:7,自引:3,他引:7
Rimokh R; Berger F; Delsol G; Digonnet I; Rouault JP; Tigaud JD; Gadoux M; Coiffier B; Bryon PA; Magaud JP 《Blood》1994,83(7):1871-1875
The t(11;14)(q13;q32) and its molecular counterpart, BCL1 rearrangement, are consistent features of mantle cell lymphoma (MCL). Rearrangement is thought to deregulate the nearby CCND1 (BCL1/PRAD1) proto-oncogene, a member of the cyclin G1 gene family, and thereby to contribute to tumorigenesis. We and others have previously shown that the BCL1 locus is rearranged in 55% to 60% of MCL patients and that, on chromosome 11, more than 80% of the breakpoints are localized within a 1-kbp DNA segment known as the major translocation cluster (MTC). We have determined the nucleotide sequence for a portion of the MTC region, and constructed chromosome 11-specific oligonucleotides that were in conjunction with a consensus immunoglobulin (Ig) heavy chain joining region (JH) primer used to perform the polymerase chain reaction (PCR) to amplify t(11;14) chromosomal junctional sequences in DNA from 16 MCL patients with breakpoints in the MTC region. 15 of the 16 breakpoints that occurred at the MTC region were amenable to PCR detection. The sizes of the amplified bands, the existence or not of a Sac I site in the PCR products, and nucleotide sequencing of the amplified DNA from four patients showed that the breakpoints share a remarkable tendency to tightly cluster within 300 bp on chromosome 11, some of them occurring at the same nucleotide. On chromosome 14, the breakpoints were localized within the Ig JH. Our findings indicate that a BCL1 rearrangement can be detected using this approach in roughly one half of the MCL patients. This has implications for both the diagnosis and the clinical management of MCL. 相似文献
92.
Kobayashi H; Montgomery KT; Bohlander SK; Adra CN; Lim BL; Kucherlapati RS; Donis-Keller H; Holt MS; Le Beau MM; Rowley JD 《Blood》1994,84(10):3473-3482
Translocations and deletions of the short arm of chromosome 12 [t(12p) and del(12p)] are common recurring abnormalities in a broad spectrum of hematologic malignant diseases. We studied 20 patients and one cell line whose cells contained 12p13 translocations and/or 12p deletions using fluorescence in situ hybridization (FISH) with phage, plasmid, and cosmid probes that we previously mapped and ordered on 12p12-13. FISH analysis showed that the 12p13 translocation breakpoints were clustered between two cosmids, D12S133 and D12S142, in 11 of 12 patients and in one cell line. FISH analysis of 11 patients with deletions demonstrated that the deletions were interstitial rather than terminal and that the distal part of 12p12, including the GDI-D4 gene and D12S54 marker, was deleted in all 11 patients. Moreover, FISH analysis showed that cells from 3 of these patients contained both a del(12p) and a 12p13 translocation and that the affected regions of these rearrangements appeared to overlap. We identified three yeast artificial chromosome (YAC) clones that span all the 12p13 translocation breakpoints mapped between D12S133 and D12S142. They have inserts of human DNA between 1.39 and 1.67 Mb. Because the region between D12S133 and D12S142 also represents the telomeric border of the smallest commonly deleted region of 12p, we also studied patients with a del(12p) using these YACs. The smallest YAC, 964c10, was deleted in 8 of 9 patients studied. In the other patient, the YAC labeled the del(12p) chromosome more weakly than the normal chromosome 12, suggesting that a part of the YAC was deleted. Thus, most 12p13 translocation breakpoints were clustered within the sequences contained in the 1.39 Mb YAC and this YAC appears to include the telomeric border of the smallest commonly deleted region. Whether the same gene is involved in both the translocations and deletions is presently unknown. 相似文献
93.
CD18-dependent and L-selectin-dependent neutrophil emigration is diminished in neonatal rabbits 总被引:1,自引:1,他引:1
Human neonatal neutrophils manifest decreases in mobility, adherence, and emigration compared with adult neutrophils that may contribute to the increased susceptibility of neonates to infection. In a developmental rabbit model, we show a reduced ability of neutrophils from 1-day-old rabbit pups to emigrate to inflamed peritoneium (3.7 +/- 0.35 x 10(6) neutrophils/mL peritoneal exudate) compared with 14-day- old (8.5 +/- 0.7 x 10(6)/mL) and adult rabbits (9.4 +/- 1.4 x 10(6) mL, P < .05) despite significantly increased blood neutrophil counts. Because the reductions in functional Mac-1 (CD11b/CD18) as well as the amount of surface L-selectin are hypothesized to be primarily responsible for the differences in human neonatal neutrophil mobility, we examined CD11b/CD18 and L-selectin in our model. Using flow cytometric analysis we found that similar to human neonates, neutrophils from 1-day-old rabbit pups had 57% of adult rabbit levels of L-selectin and, in contrast with adults, failed to show significant decreases in L-selectin after chemotactic stimulation. In addition, neutrophils from 1-day-old pups compared with adults showed a significantly diminished capacity to upregulate CD11b/CD18 after chemotactic stimulation in vitro, or after emigration to the inflamed peritoneum. Systemic administration of anti-L-selectin monoclonal antibody (MoAb) resulted in significant reduction in peritoneal neutrophils in adult (47%, P < .05) and 14-day-old rabbits (47%, P < .05), but was without effect in 1-day-old rabbits. Administration of anti-CD18 MoAb resulted in significant reduction in peritoneal neutrophil accumulation in all age groups though less in 1 day and 14 day (58% and 65%, respectively) than in adults (91%, P < .05). Only in the 14-day-old rabbits was there an additive effect of anti-L-selectin and anti-CD18 MoAbs compared with anti-CD18 alone (84% v 65%, P < .05). The findings in this in vivo rabbit model support the hypothesis that the previously described in vitro defects in human neonatal L-selectin and CD11b/CD18 may be major contributors to human neonatal inflammatory deficits. 相似文献
94.
95.
Clarence H. Braddock III MD MPH Lois Snyder JD Richard L. Neubauer MD Gary S. Fischer MD 《Journal of general internal medicine》2013,28(1):141-146
The patient-centered medical home (PCMH), with its focus on patient-centered care, holds promise as a way to reinvigorate the primary care of patients and as a necessary component of health care reform. While its tenets have been the subject of review, the ethical dimensions of the PCMH have not been fully explored. Consideration of the ethical foundations for the core principles of the PCMH can and should be part of the debate concerning its merits. The PCMH can align with the principles of medical ethics and potentially strengthen the patient–physician relationship and aspects of health care that patients value. Patient choice and these ethical considerations are central and at least as important as the economic and practical arguments in support of the PCMH, if not more so. Further, the ethical principles that support key concepts of the PCMH have implications for the design and implementation of the PCMH. This paper explores the PCMH in light of core principles of ethics and professionalism, with an emphasis both on how the concept of the PCMH may reinforce core ethical principles of medical practice and on further implications of these principles. 相似文献
96.
97.
Catherine A. Marco MD Gregory L. Larkin MD MS MSPH John C. Moskop PhD Arthur R. Derse MD JD 《Annals of emergency medicine》2000,35(6)
The practice of emergency medicine routinely requires rapid decisionmaking regarding various interventions and therapies. Such decisions should be based on the expected risks and benefits to the patient, family, and society. At times, certain interventions and therapies may be considered “futile,” or of low expected likelihood of benefit to the patient. Various interpretations of the term “futility” and its practical application to the practice of emergency medicine are explored, as well as background information and potential application of various legal, ethical, and organizational policies regarding the determination of “futility.” Decisions regarding potential benefit of interventions should be based on scientific evidence, societal consensus, and professional standards, not on individual bias regarding quality of life or other subjective matters. Physicians are under no ethical obligation to provide treatments they judge to have no realistic likelihood of benefit to the patient. Decisions to withhold treatment should be made with careful consideration of scientific evidence of likelihood of medical benefit, other benefits (including intangible benefits), potential risks of the proposed intervention, patient preferences, and family wishes. When certain interventions are withheld, special efforts should be made to maintain effective communication, comfort, support, and counseling for the patient, family, and friends. [Marco CA, Larkin GL, Moskop JC, Derse AR. Determination of “futility” in emergency medicine. Ann Emerg Med. June 2000;35:604-612.] 相似文献
98.
Brandon P. Verdoorn MD Tamara K. Evans BS Gregory J. Hanson MD Yi Zhu PhD Larissa G. P. Langhi Prata PhD Robert J. Pignolo MD PhD Elizabeth J. Atkinson MS Erin O. Wissler-Gerdes MA George A. Kuchel MD Joan B. Mannick MD Stephen B. Kritchevsky PhD Sundeep Khosla MD Stacey A. Rizza MD Jeremy D. Walston MD Nicolas Musi MD Lewis A. Lipsitz MD Douglas P. Kiel MD Raymond Yung MB ChB Nathan K. LeBrasseur PhD Ravinder J. Singh PhD Teresa McCarthy MD MS Michael A. Puskarich MD Laura J. Niedernhofer MD PhD Paul D. Robbins PhD Matthew Sorenson JD MA Tamara Tchkonia PhD James L. Kirkland MD PhD 《Journal of the American Geriatrics Society》2021,69(11):3023-3033
The burden of senescent cells (SnCs), which do not divide but are metabolically active and resistant to death by apoptosis, is increased in older adults and those with chronic diseases. These individuals are also at the greatest risk for morbidity and mortality from SARS-CoV-2 infection. SARS-CoV-2 complications include cytokine storm and multiorgan failure mediated by the same factors as often produced by SnCs through their senescence-associated secretory phenotype (SASP). The SASP can be amplified by infection-related pathogen-associated molecular profile factors. Senolytic agents, such as Fisetin, selectively eliminate SnCs and delay, prevent, or alleviate multiple disorders in aged experimental animals and animal models of human chronic diseases, including obesity, diabetes, and respiratory diseases. Senolytics are now in clinical trials for multiple conditions linked to SnCs, including frailty; obesity/diabetes; osteoporosis; and cardiovascular, kidney, and lung diseases, which are also risk factors for SARS-CoV-2 morbidity and mortality. A clinical trial is underway to test if senolytics decrease SARS-CoV-2 progression and morbidity in hospitalized older adults. We describe here a National Institutes of Health-funded, multicenter, placebo-controlled clinical trial of Fisetin for older adult skilled nursing facility (SNF) residents who have been, or become, SARS-CoV-2 rtPCR-positive, including the rationale for targeting fundamental aging mechanisms in such patients. We consider logistic challenges of conducting trials in long-term care settings in the SARS-CoV-2 era, including restricted access, consent procedures, methods for obtaining biospecimens and clinical data, staffing, investigational product administration issues, and potential solutions for these challenges. We propose developing a national network of SNFs engaged in interventional clinical trials. 相似文献
99.
Long‐term effectiveness of recommended boosted protease inhibitor‐based antiretroviral therapy in Europe 下载免费PDF全文
JR Santos A Cozzi‐Lepri A Phillips S De Wit C Pedersen P Reiss A Blaxhult A Lazzarin M Sluzhynska C Orkin C Duvivier J Bogner P Gargalianos‐Kakolyris P Schmid G Hassoun I Khromova M Beniowski V Hadziosmanovic D Sedlacek R Paredes JD Lundgren 《HIV medicine》2018,19(5):324-338
Objectives
The aim of the study was to evaluate the long‐term response to antiretroviral treatment (ART) based on atazanavir/ritonavir (ATZ/r)‐, darunavir/ritonavir (DRV/r)‐, and lopinavir/ritonavir (LPV/r)‐containing regimens.Methods
Data were analysed for 5678 EuroSIDA‐enrolled patients starting a DRV/r‐, ATZ/r‐ or LPV/r‐containing regimen between 1 January 2000 and 30 June 2013. Separate analyses were performed for the following subgroups of patients: (1) ART‐naïve subjects (8%) at ritonavir‐boosted protease inhibitor (PI/r) initiation; (2) ART‐experienced individuals (44%) initiating the new PI/r with a viral load (VL) ≤500 HIV‐1 RNA copies/mL; and (3) ART‐experienced patients (48%) initiating the new PI/r with a VL >500 copies/mL. Virological failure (VF) was defined as two consecutive VL measurements >200 copies/mL ≥24 weeks after PI/r initiation. Kaplan–Meier and multivariable Cox models were used to compare risks of failure by PI/r‐based regimen. The main analysis was performed with intention‐to‐treat (ITT) ignoring treatment switches.Results
The time to VF favoured DRV/r over ATZ/r, and both were superior to LPV/r (log‐rank test; P < 0.02) in all analyses. Nevertheless, the risk of VF in ART‐naïve patients was similar regardless of the PI/r initiated after controlling for potential confounders. The risk of VF in both treatment‐experienced groups was lower for DRV/r than for ATZ/r, which, in turn, was lower than for LPV/r‐based ART.Conclusions
Although confounding by indication and calendar year cannot be completely ruled out, in ART‐experienced subjects the long‐term effectiveness of DRV/r‐containing regimens appears to be greater than that of ATZ/r and LPV/r.100.
Devergie A; Blaise D; Attal M; Tigaud JD; Jouet JP; Vernant JP; Bordigoni P; Ifrah N; Dauriac C; Cahn JY 《Blood》1995,85(8):2263-2268
From March 1988 to March 1991, 19 French bone marrow transplant (BMT) centers participated in a prospective randomized trial comparing two conditioning regimens for patients with chronic myeloid leukemia transplanted in first chronic phase with an HLA identical sibling donor. A total of 120 consecutive patients were randomized to receive either 120 mg/kg of cyclophosphamide followed by total body irradiation (CY-TBI; n = 55) or 16 mg/kg of busulfan followed by 120 mg/kg of CY (BU-CY; n = 65). Two different TBI regimens were used. Thirteen patients received a 10-Gy single-dose TBI (SDTBI), and 42 received a fractionated TBI (FTBI). Median time between diagnosis and BMT was 315 days. Overall 5-year actuarial survival was 62.9% (65.8% +/- 12.5% for CY-TBI and 60.6 +/- 11.7% for BU-CY; P = .5), and overall disease-free survival was 55% (51% +/- 14% for CY-TBI and 59.1% +/- 11.8% for BU-CY; P = .75). All patients conditioned with CY-TBI experienced sustained engraftment; in contrast, 4 of 65 patients conditioned with BU-CY rejected the graft (P = .18). There was no significant statistical difference between the two groups regarding transplant-related mortality (29% for CY-TBI and 38% for BU-CY; P = .44). So far, with a median follow up of 42 months, 11 patients have relapsed; 9 relapses occurred after CY-TBI, mostly after FTBI (8 of 9) and 2 after BU-CY (P = .02). The actuarial risk of relapse was 4.4% +/- 6.7% after BU-CY, 11.1% +/- 20.8% after SDTBI, and 31.3% +/- 18.1% after FTBI (P = .039). In addition, independently of the conditioning regimen, the increase of posttransplant immunosuppression in 16 patients with an anti- interleukin-2 receptor monoclonal antibody (MoAb) in addition to a short course of methotrexate and cyclosporine was shown to increase the actuarial risk of relapse (57% +/- 30% with MoAb v 9% +/- 7.3% without MoAb; P = .001). We conclude that BU is an acceptable alternative to TBI for patients with chronic myeloid leukemia in first chronic phase receiving BMT from HLA identical sibling donors. Both BU-CY and CY-TBI regimens gave similar transplant-related mortality, and the antileukemic efficiency of BU-CY regimen was either similar or even higher than that of CY-TBI. 相似文献