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61.
Karam Ayoub Meera Marji Gbolahan Ogunbayo Ahmad Masri Ahmed Abdel-Latif Khaled Ziada Srikanth Vallurupalli 《JACC: Cardiovascular Interventions》2018,11(18):1862-1868
Objectives
This study sought to evaluate the impact of chronic thrombocytopenia (cTCP) on clinical outcomes after percutaneous coronary intervention (PCI).Background
The impact of cTCP on clinical outcomes after PCI is not well described. Results from single-center observational studies and subgroup analysis of randomized trials have been conflicting and these patients are either excluded or under-represented in randomized controlled trials.Methods
Using the 2012 to 2014 National (Nationwide) Inpatient Sample database, the study identified patients who underwent PCI with or without cTCP as a chronic condition variable indicator. Propensity score matching was performed using logistic regression to control for differences in baseline characteristics. The primary outcome of interest was in-hospital mortality. Secondary outcomes of interest included in-hospital post-PCI bleeding events, post-PCI blood and platelet transfusion, vascular complications, ischemic cerebrovascular accidents (CVAs), hemorrhagic CVAs, and length of stay.Results
Propensity matching yielded a cohort of 65,130 patients (32,565 with and without cTCP). Compared with those without cTCP, PCI in patients with cTCP was associated with higher risk for bleeding complications (odds ratio [OR]: 2.40; 95% confidence interval [CI]: 2.05 to 2.72; p < 0.0001), requiring blood transfusion (OR: 2.10; 95% CI: 1.80 to 2.24; p < 0.0001), requiring platelet transfusion (OR: 11.70; 95% CI: 6.00 to 22.60; p < 0.0001), higher risk for vascular complications (OR: 1.94; 95% CI: 1.43 to 2.63; p < 0.0001), ischemic CVA (OR: 1.60; 95% CI: 1.20 to 2.10; p = 0.01), and higher in-hospital mortality (OR: 2.30; 95% CI: 1.90 to 2.70; p < 0.0001), but without a significant difference in hemorrhagic CVA (OR: 1.50; 95% CI: 0.70 to 3.10; p = 0.27).Conclusions
In this large contemporary cohort, patients with cTCP were at higher risk of a multitude of complications, including higher risk of in-hospital mortality. 相似文献62.
Salih Yürek Beate Mayer Mohammed Almahallawi Axel Pruss Abdulgabar Salama 《Trasfusione del sangue》2015,13(4):616-621
Background
It is very evident that many precautions are taken regarding transfusion of red blood cells in patients with autoimmune haemolytic anaemia. Frequently, considerable efforts are made to examine the indication and serological compatibility prior to transfusion in such patients. However, at times, this may unnecessarily jeopardize patients who urgently require a red blood cell transfusion.Materials and methods
Thirty-six patients with warm-type autoimmune haemolytic anaemia were included in this study. All patients had reactive serum autoantibodies and required blood transfusion. Standard serological assays were employed for the detection and characterization of antibodies to red blood cells.Results
A positive direct antiglobulin test was observed in all 36 patients, in addition to detectable antibodies in both the eluate and serum. Significant alloantibodies were detected in the serum samples of three patients (anti-c, anti-JKa, and anti-E). In 32 patients, red blood cell transfusion was administered with no significant haemolytic transfusion reactions due to auto- and/or allo-antibodies. Due to overestimation of positive cross-matches three patients received no transfusion or delayed transfusion and died, and one patient died due to unrecognised blood loss and anaemia which was attributed to an ineffective red blood cell transfusion.Discussion
Many of the reported recommendations regarding transfusion of red blood cells in autoimmune haemolytic anaemia are highly questionable, and positive serological cross-matches should not result in a delay or refusal of necessary blood transfusions. 相似文献63.
BACKGROUND AND OBJECTIVES: Accurate identification of antibodies that sensitize red blood cells (RBCs) involves dissociating them from RBCs using an in vitro elution method that does not alter their antigen-binding properties, and analysis of the eluates against a panel of RBCs. MATERIALS AND METHODS: A method was developed that allowed efficient RBC antibody elution. Human polyclonal anti-D was used to sensitize Rh-positive RBCs, and known antigen-antibody disruptive reagents were tested using these RBCs. The best reagent conditions were optimized. Eluates made were tested and compared to results obtained with a glycine-acid-based commercial elution kit to determine efficacy. Patient samples that were positive with direct antiglobulin tests (DATs), and in vitro commercial antisera-sensitized RBCs representing clinically significant antibodies, were used for evaluating the new method. RESULTS: The formamide method was efficient at removing antibodies from RBCs. The patient samples with a positive DAT had antibodies recovered with the same specificity when compared to the acid-based technique. The length of preparation time was similar for both formamide and acid-based methods. Results of testing the eluates made from reagent RBCs sensitized with commercial antisera were distinct with antigen-positive and -negative erythrocytes. CONCLUSIONS: The formamide method compares well with acid techniques and may be an alternative choice of elution method. 相似文献
64.
BACKGROUND AND OBJECTIVES: Red blood cells (RBCs) from patients with sickle cell disease present reduced deformability. The aim of this study was to analyse the elasticity of stored RBCs from patients with the sickle cell trait (AS). MATERIALS AND METHODS: The cell elasticity was studied, using laser optical tweezers, on storage days 1, 14, 21, 28 and 35. RESULTS: The elasticity of RBC from AS units stored for 1, 14 and 21 days was significantly greater compared with that of control RBC cells stored for the same time-period. More than 30% of the cells from AS units stored for 28 or 35 days were very rigid and escaped from the optical trap. CONCLUSIONS: RBCs became rigid during storage, suggesting that haemoglobin S might compromise the cell elasticity. 相似文献
65.
Mahmoud Alhosiny Fayed Hesham El-Sayed Abdel-Hady Mona Mohammed Hafez Osama Saad Salama Youssef Abdelhalim Al-Tonbary 《Hematology/oncology and stem cell therapy》2018,11(2):65-74
Background
The increased survival rate of thalassemic patients has led to unmasking of management related complications which were infrequently encountered.Objective
Study the increased coagulation and platelet activation in children with β-thalassemia, to analyze the factors that lead to such hypercoagulable state and to study pulmonary hypertension (PH) in conjunction with platelet activation and hypercoagulable state in children with β-thalassemia.Methods
36 Egyptian children with β-thalassemia with a mean age of 9.9 years (±4.7 SD). In addition, 20 healthy Egyptian children matched for age and sex were enrolled as a control group. Both were subjected to clinical and laboratory assessments. Echocardiography was done to the patient group and PH was diagnosed based on calculated mean pulmonary artery pressure [MPAP] >25 mmHg.Results
We found that, mean ± SD serum P-selectin level (platelet activator marker) was significantly higher in thalassemic patients (2337 ± 566 pg/ml) in comparison to controls (1467 ± 247 pg/ml) (P < 0.001). Mean serum protein-C and antithrombin-III levels were significantly lower in thalassemic patients (1.2 ± 1.3 µg/ml, 27.3 ± 7.5 mg/dl) in comparison to controls (2.3 ± 1.3 µg/ml, 35.1 ± 4.1 mg/dl) (P = 0.003 and <0.001) respectively. PH was detected in 17 (47.2%) patients and it was significantly associated with splenectomy (P = 0.01) and non-transfusion dependent thalassemia (NTDT) (P = 0.04). PH was positively correlated with serum levels of P-selectin (r = 0.38, P = 0.02), fibrinogen (r = 0.41, P = 0.01) and negatively correlated with serum protein-C level (r = ?0.48, P = 0.003).Conclusion
A chronic hypercoagulable state and platelet activation is present in children with β-thalassemia. Splenectomy and transfusion infrequency are the main risk factors noted to be associated with such hypercoagulable state and platelet activation and consequently the PH among our thalassemic patients. 相似文献66.
6-MP metabolite profiles provide a biochemical explanation for 6-MP resistance in patients with inflammatory bowel disease 总被引:36,自引:0,他引:36
Dubinsky MC Yang H Hassard PV Seidman EG Kam LY Abreu MT Targan SR Vasiliauskas EA 《Gastroenterology》2002,122(4):904-915
BACKGROUND & AIMS: Approximately 40% of inflammatory bowel disease (IBD) patients fail to benefit from 6-mercaptopurine (6-MP)/azathioprine (AZA). Recent reports suggest 6-thioguanine nucleotide (6-TGN) levels (>235) independently correlate with remission. An inverse correlation between 6-TGN and thiopurine methyltransferase (TPMT) has been described. The objectives of this study were to determine whether dose escalation optimizes both 6-TGN levels and efficacy in patients failing therapy because of subtherapeutic 6-TGN levels and its effect on TPMT. METHODS: Therapeutic efficacy and adverse events were recorded at baseline and upon reevaluation after dose escalation in 51 IBD patients. 6-MP metabolite levels and TPMT activity were recorded blinded to clinical information. RESULTS: Fourteen of 51 failing 6-MP/AZA at baseline achieved remission upon dose escalation, which coincided with significant rises in 6-TGN levels. Despite increased 6-MP/AZA doses, 37 continued to fail therapy at follow-up. Dose escalation resulted in minor changes in 6-TGN, yet a significant increase in 6-methylmercaptopurine ribonucleotides (6-MMPR) (P < or = 0.01) and 6-MMPR:6-TGN ratio (P < 0.001). 6-MMPR rises were associated with dose-dependent hepatotoxicity in 12 patients (24%). TPMT was not influenced by dose escalation. CONCLUSIONS: Serial metabolite monitoring identifies a novel phenotype of IBD patients resistant to 6-MP/AZA therapy biochemically characterized by suboptimal 6-TGN and preferential 6-MMPR production upon dose escalation. 相似文献
67.
68.
Gláucia A.S. Guelsin Camila Rodrigues Jeane E.L. Visentainer Paula de Melo Campos Fabíola Traina Simone C.O. Gilli Sara T.O. Saad Lilian Castilho 《Trasfusione del sangue》2015,13(1):53-58
Background
Matching for Rh and K antigens has been used in an attempt to reduce antibody formation in patients receiving chronic transfusions but an extended phenotype matching including Fya and Jka antigens has also been recommended. The aim of this study was to identify an efficient transfusion protocol of genotype matching for patients with myelodysplastic syndrome (MDS) or chronic myelomonocytic leukaemia. We also examined a possible association of HLA class II alleles with red blood cell (RBC) alloimmunisation.Materials and methods
We evaluated 43 patients with MDS undergoing transfusion therapy with and without antibody formation. We investigated antigen-matched RBC units for ABO, D, C, c, E, e, K, Fya, Fyb, Jka, Jkb, S, s, Doa, Dob and Dia on the patients’ samples and on the donor units serologically matched for them based on their ABO, Rh and K phenotypes and presence of antibodies. We also determined the frequencies of HLA-DRB1 alleles in the alloimmunised and non-alloimmunised patients.Results
Seventeen of the 43 patients had discrepancies or mismatches for multiple antigens between their genotype-predicted profile and the antigen profile of the units of blood serologically matched for them. We verified that 36.8% of patients had more than one RBC alloantibody and 10.5% of patients had autoantibodies. Although we were able to find a better match for the patients in our extended genotyped/phenotyped units, we verified that matching for Rh and K would be sufficient for most of the patients. We also observed an over-representation of the HLA-DRB1*13 allele in the non-alloimmunised group of patients with MDS.Discussion
In our population molecular matching for C, c, E, e, K was able to reduce RBC alloimmunisation in MDS patients. An association of HLA-DRB1*13 and protection from RBC alloimmunisation should be confirmed. 相似文献69.
《Hemoglobin》2012,36(4-5):229-235
AbstractAs a type of congenital microcytic hypochromic anemia, thalassemia trait is often confused with other conditions, such as congenital sideroblastic anemia (CSA) and iron deficiency anemia, before a specific work-up is performed. However, these tests, including hemoglobin (Hb) electrophoresis, gene mutations and Prussian blue staining after bone marrow aspirate, are relatively expensive, time-consuming and invasive. To find labor-saving parameters to facilitate differential diagnosis, we retrospectively analyzed the routine blood indexes of 59 thalassemia trait cases [22 α-thalassemia (α-thal), 36 β-thalassemia (β-thal) and one α/β-thal], 21 CSA patients, and 238 iron deficiency anemia controls. Significantly higher reticulocyte Hb equivalent (Ret-He) and lower red blood cell (RBC) distribution width (RDW) were prominent in thalassemia trait. Furthermore, RDW-standard deviation (SD) was independent of the severity of anemia in thalassemia trait, similar to Ret-He in CSA. In the context of the same grades of anemia, Ret-He combined with RDW was powerful in differentiation of thalassemia from CSA and iron deficiency anemia. By receiver operation curve (ROC) analysis, Ret-He had a specificity of 67.06% and a sensitivity of 76.92% with a cutoff value of 20.9?pg for thalassemia trait in mild anemia and a specificity of 84.09% and a sensitivity of 68.42% with a cutoff value of 19.1?pg for thalassemia trait in moderate anemia. Regarding CSA, Ret-He had 92.94% specificity and 60.00% sensitivity in mild anemia, with a cutoff value of 18.1?pg. Overall, Ret-He and RDW are two convenient indexes able to differentiate thalassemia from the other two microcytic anemias, CSA and iron deficiency anemia. 相似文献
70.
目的:了解血小板献血者血液因素对采集冲红的影响。方法:检测捐献时出现冲红者和正常捐献者血小板采集前各血液因素状况,并计算本次捐献前半年捐献血小板次数,进行统计分析。结果:以RBC等11个因素为自变量进行单因素Logistic回归分析,RBC、HGB、HCT、MCV、MCHC、PDW、MPV、P-LCR、RDW-CV、半年内献血次数均不具有意义,而MCH异常者冲红的概率平均是正常者的9.726倍。拟合方程:P=e-0.429+2.275x/(1+e-0.429+2.275x)。结论:献血者单采前MCH是影响是否出现冲红现象的重要因素。 相似文献