全文获取类型
收费全文 | 23528篇 |
免费 | 1851篇 |
国内免费 | 77篇 |
专业分类
耳鼻咽喉 | 393篇 |
儿科学 | 819篇 |
妇产科学 | 376篇 |
基础医学 | 2417篇 |
口腔科学 | 526篇 |
临床医学 | 2126篇 |
内科学 | 5189篇 |
皮肤病学 | 548篇 |
神经病学 | 1272篇 |
特种医学 | 1107篇 |
外国民族医学 | 1篇 |
外科学 | 4542篇 |
综合类 | 329篇 |
一般理论 | 15篇 |
预防医学 | 1153篇 |
眼科学 | 812篇 |
药学 | 2033篇 |
中国医学 | 38篇 |
肿瘤学 | 1760篇 |
出版年
2023年 | 196篇 |
2022年 | 326篇 |
2021年 | 985篇 |
2020年 | 473篇 |
2019年 | 814篇 |
2018年 | 942篇 |
2017年 | 611篇 |
2016年 | 647篇 |
2015年 | 672篇 |
2014年 | 1011篇 |
2013年 | 1180篇 |
2012年 | 1739篇 |
2011年 | 1710篇 |
2010年 | 869篇 |
2009年 | 815篇 |
2008年 | 1278篇 |
2007年 | 1208篇 |
2006年 | 1125篇 |
2005年 | 977篇 |
2004年 | 885篇 |
2003年 | 749篇 |
2002年 | 647篇 |
2001年 | 587篇 |
2000年 | 550篇 |
1999年 | 488篇 |
1998年 | 165篇 |
1997年 | 141篇 |
1996年 | 145篇 |
1995年 | 144篇 |
1994年 | 115篇 |
1993年 | 102篇 |
1992年 | 268篇 |
1991年 | 285篇 |
1990年 | 250篇 |
1989年 | 214篇 |
1988年 | 209篇 |
1987年 | 221篇 |
1986年 | 194篇 |
1985年 | 178篇 |
1984年 | 112篇 |
1983年 | 127篇 |
1982年 | 85篇 |
1981年 | 70篇 |
1980年 | 59篇 |
1979年 | 129篇 |
1978年 | 79篇 |
1977年 | 69篇 |
1975年 | 59篇 |
1974年 | 65篇 |
1973年 | 88篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Shikha Patel Xingjian Liu Ming Liu Ralph Stephani Hardik Patel Jerome Cantor 《Lung》2014,192(5):803-810
Introduction
Previous studies from this laboratory indicate that endothelin-1 (ET-1), a potent vasoconstrictor, may play an important role in lipopolysaccharide (LPS)-induced release of neutrophils from the pulmonary microvasculature. To further test this concept, Syrian hamsters were treated with a novel endothelin receptor A (ETA) antagonist (HJP272) prior to intratracheal instillation of LPS.Methods
The effect of HJP272 on the LPS-induced inflammatory reaction was determined by measuring: (1) lung histopathological changes, (2) total neutrophils in bronchoalveolar lavage fluid (BALF), (3) expression of tumor necrosis factor receptor 1 (TNFR1) by BALF macrophages, and (4) alveolar septal cell apoptosis.Results
Treatment with HJP272 significantly reduced each of these parameters during a 24-hr period following LPS instillation, supporting the concept that limiting the activity of ET-1 may reduce the extent of lung injury. This hypothesis was further tested by giving ET-1 prior to LPS instillation, which resulted in a marked enhancement of LPS-induced lung inflammation, as measured by BALF neutrophils and TNFR1-positive macrophages. Furthermore, the increase in neutrophils resulting from treatment with ET-1 was significantly reduced by HJP272, again demonstrating the ability of ETA receptor antagonists to limit the influx of these cells into the lung.Conclusions
These findings suggest a potential therapeutic role for these agents in diseases where neutrophils are a significant cause of lung injury, such as bronchopneumonia, respiratory distress syndrome, and chronic obstructive pulmonary disease. 相似文献992.
James B. Bussel Christina S. Lee Caroline Seery Allison A. Imahiyerobo Michaela V. Thompson Diane Catellier Ithamar G. Turenne Vivek L. Patel Paul A. Basciano Rebecca L. Elstrom Waleed Ghanima 《Haematologica》2014,99(7):1264-1271
Adults with newly diagnosed or persistent immunothrombocytopenia frequently relapse upon tapering steroids; adults and children with chronic disease have an even lower likelihood of lasting response. In adults with newly-diagnosed immunothrombocytopenia, two studies showed that dexamethasone 40 mg/day × four days and 4 rituximab infusions were superior to dexamethasone alone. Studies have also shown three cycles of dexamethasone are better than one and patients with persistent/chronic immunothrombocytopenia respond less well to either dexamethasone or rituximab. Therefore, 375 mg/m2 × 4 rituximab was combined with three 4-day cycles of 28 mg/m2 (max. 40 mg) dexamethasone at 2-week intervals and explored in 67 ITP patients. Best long-term response was assessed as complete (platelet count ≥100×109/L) or partial (50–99×109/L). Only 5 patients had not been previously treated. Fifty achieved complete (n=43, 64%) or partial (n=7, 10%) responses. Thirty-five of 50 responders maintained treatment-free platelet counts over 50×109/L at a median 17 months (range 4–67) projecting 44% event-free survival. Duration of immunothrombocytopenia less than 24 months, achieving complete responses, and being female were associated with better long-term response (P<0.01). Adverse events were generally mild-moderate, but 3 patients developed serum sickness and 2 colitis; there were no sequelae. Dexamethasone could be difficult to tolerate. Fourteen patients became hypogammaglobulinemic and half had increased frequency of minor infections; 9 of 12 evaluable patients recovered their IgG levels. Rituximab combined with three cycles of dexamethasone provides apparently better results to reported findings with rituximab alone, dexamethasone alone, or the combination with one cycle of dexamethasone. The results suggest medical cure may be achievable in immunothrombocytopenia, especially in women and in patients within two years of diagnosis. (clinicaltrials.gov identifier:02050581) 相似文献
993.
Abhishek A. Mangaonkar Fahim Thawer James Son Germame Ajebo Hongyan Xu Nadine J. Barrett Leigh G. Wells Latanya Bowman Betsy Clair Niren Patel Pritam Bora Grace Jung Elizabeta Nemeth Abdullah Kutlar 《British journal of haematology》2020,189(6):1204-1209
Sickle cell disease (SCD) has a distinct pattern of transfusional iron overload (IO) when compared to transfusion-dependent β-thalassaemia major (TDT). We conducted a single institution prospective study to evaluate plasma biomarkers of iron regulation and inflammation in patients with SCD with IO (SCD IO cases, n = 22) and without IO (SCD non-IO cases, n = 11), and non-SCD controls (n = 13). Hepcidin was found to be inappropriately low, as evidenced by a significantly higher median hepcidin/ferritin ratio in non-SCD controls compared to SCD IO cases (0·3 vs. 0·02, P < 0·0001) and SCD non-IO cases (0·3 vs. 0·02, P < 0·0001), suggesting that certain inhibitory mechanism (s) work to suppress hepcidin in SCD. As opposed to the SCD non-IO state, where hepcidin shows a strong significant positive correlation with ferritin (Spearman ρ = 0·7, P = 0·02), this correlation was lost when IO occurs (Spearman ρ = −0·2, P = 0·4). Although a direct non-linear correlation between erythroferrone (ERFE) and hepcidin did not reach statistical significance both in the IO (Spearman ρ = −0·4, P = 0·08) and non-IO state (Spearman ρ = −0·6, P = 0·07), patients with highest ERFE had low hepcidin levels, suggesting that ERFE contributes to hepcidin regulation in some patients. Our results suggest a multifactorial mechanism of hepcidin regulation in SCD. 相似文献
994.
Hassan Awada Reda Z. Mahfouz Ashwin Kishtagari Teodora Kuzmanovic Jibran Durrani Cassandra M. Kerr Bhumika J. Patel Valeria Visconte Tomas Radivoyevitch Alan Lichtin Hetty E. Carraway Jaroslaw P. Maciejewski Yogen Saunthararajah 《British journal of haematology》2020,188(6):924-929
The nucleoside analogue decitabine can deplete the epigenetic regulator DNA methyltransferase 1 (DNMT1), an effect that occurs, and is saturated at, low concentrations/doses. A reason to pursue this molecular-targeted effect instead of the DNA damage/cytotoxicity produced with high concentrations/doses, is that non-cytotoxic DNMT1-depletion can cytoreduce even p53-null myeloid malignancies while sparing normal haematopoiesis. We thus identified minimum doses of decitabine (0·1–0·2 mg/kg) that deplete DNMT1 without off-target anti-metabolite effects/cytotoxicity, and then administered these well-tolerated doses frequently 1–2X/week to increase S-phase dependent DNMT1-depletion, and used a Myeloid Malignancy Registry to evaluate long-term outcomes in 69 patients treated this way. Consistent with the scientific rationale, treatment was well-tolerated and durable responses were produced (~40%) in genetically heterogeneous disease and the very elderly. 相似文献
995.
996.
997.
Snehalata C. Gupte Pratima N. Patel 《Indian journal of hematology & blood transfusion》2014,30(3):175-179
The study presents the data analysis (1) To find out the trend of blood component use during the period 2003–2010 and to determine impact of component awareness programs on reduction in whole blood (WB) and single unit transfusions. (2) To determine Hb trigger. The details about blood units issued were entered in the integrated blood bank management software as well as in Microsoft Excel. The data of 4,838 cases of pregnancy anemia; 2,244 receiving blood for obstetric (Ob) hemorrhage including 270 cases of disseminated intravascular coagulation; 1,413 women having Gynecological (Gy) bleeding; 911 Ob, 2,032 Gy and 740 surgeries for Gy malignancy were analyzed. During the years 2003–2010 there was gradual increase in component utilization for pregnancy anemia, Ob/Gy surgeries and Ob/Gy bleeding and significant reduction in WB transfusions due to component awareness programs. But single unit transfusions showed comparatively lower trend of reduction. The mean Hb was 6.4 g/dL for pregnancy anemia, 8.1 g/dL for surgeries and 7.3 g/dL for Ob/Gy bleeding. 相似文献
998.
Manisha M. Brahmbhatt Pina J. Trivedi Dharmesh M. Patel Shilin N. Shukla Prabhudas S. Patel 《Indian journal of hematology & blood transfusion》2014,30(4):241-246
The BCR/ABL gene rearrangement is cytogenetically visualized in most chronic myeloid leukemia (CML) cases. About 5–10 % of CML patients lack its cytogenetic evidence, however, shows BCR/ABL fusion by molecular methods. We describe two CML patients with Philadelphia (Ph) negative (−ve) and BCR/ABL positive by fluorescence in situ hybridization (FISH). Both the cases were in chronic phase at diagnosis. Conventional cytogenetics and different FISH assays were adopted using BCR/ABL probes. Home-brew FISH assay using bacterial artificial clone (BAC) for BAC-CTA/bk 299D3 for chromosomal region 22q13.31-q13.32 was performed in case 1. Both the patients were Ph-ve. In first case, dual color dual fusion (DCDF)-FISH studies revealed 1 Red (R) 2 Green (G) 1 Fusion (F) signal pattern in 80 % of cells indicating BCR/ABL fusion signals on chromosomes 9 instead of Ph and 2G2F signal pattern in 20 % of cells indicating two BCR/ABL fusions on both chromosomes 9q34 on presentation. In second case, FISH studies revealed the 1R1G1F signal pattern indicating BCR/ABL fusion signals on chromosomes 9 instead of Ph in 100 % of cells at presentation. During follow-up, both the patients exhibited 2G2F signal pattern indicating two BCR/ABL fusions on both chromosomes 9q34, which indicated a clonal evolution in 100 % cells. Both the patients did not achieve therapeutic response. Relocation of BCR/ABL fusion sequence on sites other than 22q11 represents a rare type of variant Ph, the present study highlights the hot spots involved in CML pathogenesis and signifies their implications in Ph−ve BCR/ABL positive CML. This study demonstrated the genetic heterogeneity of this subgroup of CML and strongly emphasized the role of metaphase FISH, especially in Ph−ve CML cases, as it detects variations of the classical t(9;22). 相似文献
999.
1000.
Shalender Bhasin MB BS Thomas G. Travison PhD Todd M. Manini PhD Sheena Patel MS Karol M. Pencina PhD Roger A. Fielding PhD Jay M. Magaziner PhD Anne B. Newman MD MPH Douglas P. Kiel MD Cyrus Cooper DM FMedSci Jack M. Guralnik MD PhD Jane A. Cauley Dr.PH Hidenori Arai MD PhD Brian C. Clark PhD Francesco Landi MD PhD Laura A. Schaap PhD Suzette L. Pereira PhD Daniel Rooks PhD Jean Woo MD PhD Linda J. Woodhouse PhD Ellen Binder MD Todd Brown MD Michelle Shardell PhD Quian-Li Xue PhD Ralph B. DʼAgostino Sr PhD Denise Orwig PhD Greg Gorsicki PhD Rosaly Correa-De-Araujo MD PhD Peggy M. Cawthon PhD 《Journal of the American Geriatrics Society》2020,68(7):1410-1418