全文获取类型
收费全文 | 1601篇 |
免费 | 93篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 97篇 |
妇产科学 | 23篇 |
基础医学 | 226篇 |
口腔科学 | 35篇 |
临床医学 | 129篇 |
内科学 | 330篇 |
皮肤病学 | 33篇 |
神经病学 | 76篇 |
特种医学 | 25篇 |
外科学 | 179篇 |
综合类 | 48篇 |
一般理论 | 3篇 |
预防医学 | 82篇 |
眼科学 | 57篇 |
药学 | 110篇 |
中国医学 | 4篇 |
肿瘤学 | 227篇 |
出版年
2023年 | 28篇 |
2022年 | 32篇 |
2021年 | 81篇 |
2020年 | 51篇 |
2019年 | 66篇 |
2018年 | 64篇 |
2017年 | 49篇 |
2016年 | 50篇 |
2015年 | 50篇 |
2014年 | 69篇 |
2013年 | 83篇 |
2012年 | 133篇 |
2011年 | 132篇 |
2010年 | 73篇 |
2009年 | 45篇 |
2008年 | 83篇 |
2007年 | 55篇 |
2006年 | 53篇 |
2005年 | 45篇 |
2004年 | 64篇 |
2003年 | 45篇 |
2002年 | 40篇 |
2001年 | 22篇 |
2000年 | 18篇 |
1999年 | 20篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1992年 | 5篇 |
1990年 | 9篇 |
1989年 | 12篇 |
1988年 | 10篇 |
1987年 | 10篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1980年 | 11篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1975年 | 7篇 |
1974年 | 9篇 |
1973年 | 10篇 |
1972年 | 7篇 |
1970年 | 13篇 |
1969年 | 8篇 |
1968年 | 7篇 |
1967年 | 8篇 |
1939年 | 4篇 |
排序方式: 共有1698条查询结果,搜索用时 15 毫秒
991.
992.
993.
Nitin Ohri Balazs Halmos William R. Bodner Haiying Cheng Madhur K. Garg Rasim Gucalp Chandan Guha 《Practical radiation oncology》2021,11(2):e172-e179
PurposeAdjuvant durvalumab is now recommended for most patients with locally advanced non-small cell lung cancer after concurrent chemoradiotherapy. Herein, we explore the clinical factors that may be associated with the benefit from adjuvant durvalumab.Methods and MaterialsPatients with non-small cell lung cancer who were treated with definitive concurrent chemoradiotherapy at our institution between August 2013 and May 2019 were included in this analysis. Clinical and treatment characteristics were tested for associations with progression-free survival (PFS) in Cox models. Interaction terms were added to the PFS Cox models to explore factors that may modulate the effects of adjuvant durvalumab. PFS and overall survival (OS) rates were estimated using the Kaplan-Meier method, and comparisons between patient subgroups were performed using log rank testing.ResultsA total of 105 patients met the eligibility criteria. Thirty-five patients (33%) received adjuvant durvalumab. Treatment with durvalumab was associated with significant improvement in PFS (1-year PFS: 67% vs 39%; log rank P = .006) and OS (1-year OS: 88% vs 76%; log rank P = .041). Exploratory analyses identified the neutrophil-to-lymphocyte ratio (NLR) after radiation therapy (RT) as a factor that may be associated with a benefit from durvalumab. For patients with post-RT NLR exceeding the cohort’s median value of 4.3, receipt of adjuvant durvalumab was not associated with a significant PFS improvement (1-year PFS: 45% vs 36%; log rank P = .702). For patients with post-RT NLR <4.3, durvalumab receipt was associated with improved PFS (69% vs 41%; P = .009). High mean RT doses delivered to the heart and esophagus were associated with high post-RT NLR.ConclusionsWe identified low NLR after chemoradiotherapy as a factor that may be associated with a benefit from adjuvant durvalumab. Validation studies are warranted. 相似文献
994.
Malmstrom K Sapre A Couglin H Agrawal NG Mazenko RS Fricke JR 《Clinical therapeutics》2004,26(5):667-679
BACKGROUND: Patients experiencing acute pain after surgery, including dental surgery, often require analgesia. Ideally, the chosen analgesic should have a rapid onset and sustained effect. Etoricoxib is a new cyclooxygenase-2-selective inhibitor that has demonstrated analgesic efficacy in the treatment of acute pain with a rapid onset and long-lasting pain relief. OBJECTIVE: The goal of this study was to determine the analgesic effect of single oral doses of etoricoxib 60, 120, 180, and 240 mg compared with placebo in the treatment of pain after dental surgery. Ibuprofen was used as an active control. METHODS: This was a randomized, double-blind, parallel-group, single-dose, placebo- and active comparator-controlled study performed at a single center. It consisted of 3 visits (prestudy, treatment, and poststudy). Eligible patients were aged > or =16 years with moderate or severe pain after surgical extraction of > or =2 third molars, of which > or =1 was an impacted mandibular molar. Patients were assessed over 24 hours and reported pain intensity and pain relied at 14 predefined time points. Plasma samples for a pharmacokinetic/pharmacodynamic analysis were collected from a subset of patients at baseline and the 14 predefined time points. The end points included total pain relief over 8 hours (TOPAR8, the primary end point), sum of pain intensity difference over 8 hours, patient's global evaluation of treatment, median time to onset of pain relief (2-stopwatch method), peak pain relief, and duration of analgesic effect (median time to use of rescue medication). Adverse events were collected up to 14 days postdose. RESULTS: Three hundred ninety-eight (63.1% women, 36.9% men; mean age, 21.1 years; 72.1% white, 27.9% other; mean number of third molars removed, 3.5; 65.2% experiencing moderate pain) were randomly allocated to receive etoricoxib 60 mg (n = 75), etoricoxib 120 mg (n = 76), etoricoxib 180 mg (n = 74), etoricoxib 240 mg (n = 76), ibuprofen 400 mg (n = 48), and placebo (n = 49). All active treatments had significantly greater overall analgesic effect (TOPAR8) compared with placebo (P < or 0.001). Patients who received etoricoxib 120 and 180 mg had significantly higher TOPAR8 scores than those who received etoricoxib 60 mg ( P < = 0.001) and ibuprofen (P < 0.05 etoricoxib 120 mg; P < or = 0.001 etoricoxib 180 mg). Least-squares mean TOPAR8 scores for etoricoxib 60, 120, 180, and 240 mg, ibuprofen, and placebo were 16.0, 22.0, 23.5, 20.7, 18.6, and 5.2, respectively. The median time to onset of analgesia was 24 minutes for etoricoxib 120, 180, and 240 mg, and 30 minutes for etoricoxib 60 mg and ibuprofen. There were no significant differences in the onset of analgesia between etoricoxib 120, 180, and 240 mg and ibuprofen. The duration of analgesic effect was >24 hours for etoricoxib 120, 180, and 240 mg, and 12.1 hours for etoricoxib 60 mg. The duration of effect was significantly longer with all 4 etoricoxib doses compared with ibuprofen (10.1 hours; P < 0.05 etoricoxib 60 mg; < or = 0.001etoricoxib 120, 180, and 240 mg) and compared with placebo (2.1 hours; P < = 0.001). In the pharmacokinetic/pharmacodynamic analysis (n approximately 120), there was a linear relationship between plasma etoricoxib concentrations and pain relief scores up to the maximum observed concentration, followed by a decline in plasma concentrations with persistent analgesia. The most common adverse events were postextraction alveolitis and nausea. Conclusions: In this dose-ranging study, etoricoxib 120 mg was determined to be the minimum dose that had maximal efficacy in patients with moderate to severe acute pain associated with dental surgery. Both etoricoxib and ibuprofen were generally well tolerated. 相似文献
995.
Bradley Kay Fouad Chouairi Katherine A.A. Clark Samuel W. Reinhardt Michael Fuery Avirup Guha Tariq Ahmad Ryan K. Kaple Nihar R. Desai 《Mayo Clinic proceedings. Mayo Clinic》2021,96(6):1522-1529
In 2013, the Food and Drug Administration approved the first transcatheter mitral valve repair (TMVr) device for degenerative mitral regurgitation for patients at prohibitive surgical risk. To better understand contemporary utilization trends and outcomes, we reviewed hospitalizations, identified using International Classification of Diseases, Ninth Revision and International Classification of Diseases, Tenth Revision codes, in which the patient underwent TMVr or mitral valve repair (MVr) with a diagnosis of mitral regurgitation, without stenosis, from the National (Nationwide) Inpatient Sample from 2014 to 2017. We included 10,020 hospitalizations in which the patient underwent TMVr and 5845 in which the patient underwent MVr and assessed trends in demographic characteristics, patient comorbidities, total hospital charges, and outcomes. Transcatheter mitral valve repair experienced exponential growth, increasing from 150 to 5115 over the study period (P<.001 for trend), whereas MVr grew to a lesser degree. The median length of stay for TMVr decreased from 4 to 2 days; mortality declined from 3.3% to 1.6% (P<.001 for both). Both TMVr and MVr rates of discharge home increased over the study period. Total charges for TMVr increased from $149,582 to $178,109, whereas those for MVr increased to a lesser degree, from $149,426 to $157,146 (P<.001 for both). Discharge disposition, length of stay, and in-hospital mortality all exhibited favorable trends for both procedures. Caution must be exercised in direct comparisons between procedures as they target somewhat different populations. With expanded indications for TMVr, we anticipate further increases in procedural volume, although the effect on MVr remains unclear. 相似文献
996.
Animesh Kumar Datta Aninda Mandal Debadrito Das Sudha Gupta Aditi Saha Rita Paul Sonali Sengupta Sandip Halder Subikash Biswas 《Proceedings of the National Academy of Sciences, India. Section B.》2016,86(3):513-522
Polyploidy in angiosperm is a well discussed phenomenon for last few decades but still the proper mechanism and its consequences remain to be an enigma. The present review revisited the phenomenon of polyploidy in angiosperms considering many aspects like genome merging and duplication, restructuring of genome, gene silencing, genome size dynamics, meiotic pairing behaviour of homologues, adaptive significance, relationship between C-value and DNA content among others and a few key questions are raised. It is rather difficult to understand whether all of these regulatory events under the ecological niche are unilateral forces or act as tools of a unified selection machinery of evolution, speciation and diversification. The present discussion may provide genetic insight on the phenomenon in an explicit dimension for proper understanding of evolutionary biology. 相似文献
997.
With the advent of rapid sequencing technologies, making sense of all the genomic variations that we see among us has been a major challenge. A plethora of algorithms and methods exist that try to address genome interpretation through genotype–phenotype linkage analysis or evaluating the loss of function/stability mutations in protein. Critical Assessment of Genome Interpretation (CAGI) offers an exceptional platform to blind‐test all such algorithms and methods to assess their true ability. We take advantage of this opportunity to explore the use of molecular dynamics simulation as a tool to assess alteration of phenotype, loss of protein function, interaction, and stability. The results show that coarse‐grained dynamics based protein flexibility analysis on 34 CHEK2 and 1719 CALM1 single mutants perform reasonably well for class‐based predictions for phenotype alteration and two‐thirds of the predicted scores return a correlation coefficient of 0.6 or more. When all‐atom dynamics is used to predict altered stability due to mutations for Frataxin protein (8 cases), the predictions are comparable to the state‐of‐the‐art methods. The competitive performance of our straightforward approach to phenotype interpretation contrasts with heavily trained machine learning approaches, and open new avenues to rationally improve genome interpretation. 相似文献
998.
Bandyopadhyay A Chakraborty J Choudhuri MK Guha D Mallick MG Roy S Mitra K 《Indian journal of pathology & microbiology》2007,50(4):780-782
Recurrent chondroblastoma with pulmonary and palatal metastasis is a rare occurrence. We report the cytological and histological findings of such a case in a 33 years old male, where the primary diagnosis of metastatic chondroblastoma was made on FNAC, which was later confirmed on histopathology. The present case highlights that, some chondroblastomas do exist, that are capable of pursuing a malignant course. 相似文献
999.
Raju GM Guha S Mukhopadhyay A Kumar L Kale VP Mittal S Deka D Mohanty S Kochupillai V 《Journal of hematotherapy & stem cell research》2003,12(5):491-497
Previously, we and others have shown that fetal liver infusion (FLI) leads to autologous hematopoietic improvement in 40-54% of patients with aplastic anemia. However, whether this recovery was spontaneous or the effect of the infused liver cells was not clear. To dissect the role of FLI in autologous hematopoietic recovery, the colony-supporting potential of fetal liver-conditioned medium (FLCM) was evaluated in bone marrow (BM) cells of normal adult and aplastic anemia patients. In both cases, each sample of FLCM supported the growth of colony-forming cells in semi solid culture medium. The FLCM was assayed for the presence of four principal colony-stimulating cytokines, namely stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and erythropoietin (Epo). While GM-CSF, IL-3, and Epo were present in insignificant amounts or were altogether absent, 50-635 pg/ml of SCF was found in 8 of the 13 FLCM samples tested. Preliminary results of bioneutralization assay indicated the possible role of SCF, secreted by the FL cells, in colony-supporting activity of aplastic anemia and normal BM cells. Overall, our in vitro study implicates the paracrine role of infused FL cells in regenerating autologous hematopoiesis in aplastic anemia patients. 相似文献
1000.
S K Panda R Datta A Gupta R S Kamat N Madangopalan M K Bhan B Rath D K Guha N C Nayak 《Tropical gastroenterology》1989,10(2):106-110
The relative magnitude by hepatitis A virus (HAV), hepatitis B virus (HBV) and hepatitis Non-A, Non-B virus (HNANBV) was determined in 496 children from three different parts of India suffering from acute viral hepatitis by tests for specific IgM class anti-HAV and anti-HBV antibodies in the serum. HAV, HBV and NANB infections accounted for 55.8 per cent, 20.2 per cent and 23.2 per cent of cases respectively. Hepatitis A largely (59.5%) affected younger children of 1-5 yr. Nearly a third of children affected by NANB hepatitis were additionally positive for HBsAg. The proportions of HAV and HBV infected cases respectively decreased and increased with increasing age whereas the incidence of HNANBV infection remained almost constant throughout childhood. Acute NANB hepatitis, a major health problem in the adults of India is also common throughout childhood. This study suggests that this infection does not impart long lasting protective immunity. 相似文献