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Autoantibody production in autoimmune haemolytic anemia (AIHA) is the result of the loss of self-immunological tolerance of the host. Here we investigated the various immunohematological markers that may influence the severity of in vivo hemolysis in warm AIHA (WAIHA). Complete direct antiglobulin test (DAT) evaluation and immunohematological characterization were performed in 247 patients of WAIHA following departmental protocols. Clinical and laboratory details of patients were obtained from patient file. The median age of WAIHA patients was 47 years with a female preponderance. Lymphoproliferative diseases were the major underlying causes of secondary WAIHA. The mean haemoglobin (Hb) and reticulocyte count (Retic) were 6.43 gm/dL and 7.58% respectively. Single autoantibody bound to red cells was investigated in 151 patients. The main IgG subclass was IgG1. Multiple autoantibodies like IgG+ C, IgG+IgA and IgG+IgA+C were found in 87 (35.2%) patients. Free autoantibodies were observed in 112 patients with a median indirect antiglobulin test (IAT) reactivity of 2+. Derangement of haematological and biochemical values was statistically significant with increase in DAT reactivity, presence of multiple autoantibodies on red cells, coating of red cells by IgG3 or multiple IgG subclass, higher DAT dilution and increasing IAT reactivity. We conclude that several important but simple immunohematological parameters may influence the degree of in vivo hemolysis in WAIHA. Since a set of common haematological and biochemical test determines the severity of in vivo hemolysis therefore a comprehensive clinical and immunohematological evaluation is advisable for a correct diagnostic and therapeutic workup of WAIHA.  相似文献   
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Hemolysis is a potential limitation of percutaneously delivered left‐sided mechanical circulatory support pumps, including trans valvular micro‐axial flow pumps (TVP). Hemolytic biomarkers among durable left ventricular assist devices include lactate dehydrogenase (LDH) >2.5 times the upper limit of normal (ULN) and plasma‐free hemoglobin (pf‐Hb) >20 mg/dL. We examined the predictive value of these markers among patients with cardiogenic shock (CS) receiving a TVP. We retrospectively studied records of 116 consecutive patients receiving an Impella TVP at our institution between 2012 and 2017 for CS. Twenty‐three met inclusion/exclusion criteria, and had sufficient pf‐Hb data for analysis. Area under receiver‐operator characteristic (ROC) curve for diagnosing hemolysis were calculated. Mean age was 62 ± 14 years and ejection fraction was 15 ± 5%. Mean duration of support was 5.4 ± 3.5 days. Pre‐device LDH levels were >2.5x ULN in 71% (n = 5/7) of 5.0 and 29% of CP patients, while pre‐device pf‐Hb levels were >20 mg/dL in 14% (n = 1/7) of 5.0 and 25% (n = 4/16) of CP patients. Given elevated baseline LDH and pf‐Hb levels, we defined hemolysis as a pf‐Hb level >40 mg/dL within 72 h post‐implant plus clinical evidence of device‐related hemolysis. We identified that 30% (n = 7/23) had device‐related hemolysis. Using ROC curve‐derived cut‐points, an increase in delta pf‐Hb by >27mg/dL, not delta LDH, within 24 h after TVP implant (delta pf‐Hb: C‐statistic = 0.79, sensitivity: 57%, specificity: 93%, p <0.05) was highly predictive of hemolysis. In conclusion, we identified a change in pf‐Hb, not LDH, levels is highly sensitive and specific for hemolysis in patients treated with a TVP for CS.  相似文献   
4.
BACKGROUNDIndices such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume (MPV), platelet distribution width (PDW), and red cell distribution width (RDW) are considered new markers of the systemic inflammatory response (SIR), and have been widely implemented for the diagnosis of patients with inflammatory diseases. These new indicators have also been widely investigated in preeclampsia (PE) but less analyzed in hemolysis, elevated liver enzymes, and low platelet (HELLP) syndrome.AIMTo compare SIR markers among HELLP patients, PE only patients, and healthy gravidae.METHODSThis retrospective case-control study enrolled 630 cases, including 210 patients with HELLP syndrome (HELLP group), 210 patients with only PE (PE group) and 210 healthy gravidae (control group). The three groups were matched by age, parity, status of assisted reproduction, and multiple pregnancies. Birthweight, gestational age at complete blood count collection, gestational age at delivery, mode of delivery, etc. were recorded. The main indices as NLR, PLR, MPV, PDW, and RDW among the groups were compared, as well as some secondary outcomes including neutrophil, platelets, and hemoglobin.RESULTSThe NLR (6.4 vs 4.3 vs 3.5), MPV (11.9 vs 11.2 vs 10.7), PDW (16.4 vs 13.3 vs 14.2), leukocyte (12.4 × 109/L vs 9.7 × 109/L vs 8.7 × 109/L) and neutrophil count (9.9 × 109/L vs 7.3 × 109/L vs 6.1 × 109/L) were highest in the HELLP group, lower in the PE group, and lowest in the control group. Both the overall comparisons between the three groups (all bP < 0.01) and pairwise comparisons between every two groups elicited statistically significant differences (all dP < 0.01, except control vs PE: cP < 0.05 in PDW). The average lymphocyte counts were 1.4 (1.1, 2.0) × 109/L in the HELLP group, 1.6 (1.3, 2.0) × 109/L in the PE group and 1.7 (1.4, 2.0) × 109/L in the control group. The overall comparison of lymphocyte count within the three groups had statistically significant differences (P = 0.000). The pairwise comparisons between every two groups demonstrated that the HELLP group had a lower lymphocyte count than both the PE (P = 0.019) and control groups (P = 0.000), but the difference between the PE and control groups was not statistically significant (P = 0.432). The overall comparisons on platelet counts and the PLR among these three groups also showed statistically significant differences (both P = 0.000), from low to high being those in the HELLP group (43.4 × 109/L, 64.0), control group (180.5 × 109/L, 103.6) and PE group (181.5 × 109/L, 112.8). Pairwise comparisons of neither index displayed statistically significant differences between the PE and control groups (both P > 0.05), while the differences in the two indices between the HELLP group and the two other groups were still statistically significant (all P = 0.000). RDW values were highest in the HELLP group (14.5% [13.6, 15.3]), lower in the control group (14.1% [13.5, 14.8]) and lowest in the PE group (13.9% [13.4, 14.9]). The difference between the PE and control group did not show statistical significance (P = 1.000), while RDW values in the HELLP group were higher than those in the other two groups (cP < 0.05 vs control, dP < 0.01 vs PE).CONCLUSIONSIR markers such as NLR, RDW, MPV, and PDW were increased and PLR was decreased in HELLP. These SIR markers may become new indicators in the evaluation of HELLP syndrome.  相似文献   
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目的近年来,临床样本的检测中,免疫性溶血性输血反应(IHTR)样本检出率不断增加。同时,毛细管离心技术、PEG增强技术、微柱凝集卡技术等逐渐普及应用,这些技术上的变化可能影响IHTR检出率。为了减少IHTR漏检,有必要对以往IHTR样本特点进行总结,分析造成临床漏检的可能原因,以及实验室及时发现IHTR的检测技术关键。方法回顾2011年3月~2021年3月,上海市血液中心血型参比实验室检出的IHTR案例。纳入案例需同时符合:有近期输血史;检出同种抗体;检出或确认输入了与该同种抗体反应的红细胞。所有入组样本中,不包括新生儿及检出自身抗体的案例,以防止来自产妇的被动免疫抗体和"类同种自身抗体"的干扰。对所有纳入的案例,统计抗体特异性、效价、直抗、患者诊断、血红蛋白及性别年龄分布、输血至检出溶血反应的时间等特征。结果IHTR样本共100例,患者诊断以肿瘤、MDS(骨髓异常增生综合征)居多;其中Rh系统抗体造成的溶血性输血反应占78%,Kidd系统造成的输血反应占11%,涉及抗体大多效价较低80%≤4;患者直抗可持续阳性超过8周;年龄分布不存在性别差异。结论溶血性输血反应可使受血者产生溶血,可能严重危害患者生命安全。IHTR样本中抗体大多为Rh系统抗体,通过Rh同型输注可有效降低IHTR的发生率。通过统计还发现,造成溶血的抗体普遍较弱,且输入的不配合红细胞在体内迅速代谢,使IHTR容易被漏检,造成反复输入不配合红细胞,危及患者生命。在检测技术上,有必要提高检测的灵敏度,应用毛细管离心分离技术对IHTR的检测有较大的帮助。  相似文献   
7.
A 41-year-old man with a continuous- flow left ventricular assist device presented for evaluation of dysphagia and dark urine. He was found to have a significantly elevated L-lactate dehydrogenaseand an elevated plasma free hemoglobin consistent with intravascular hemolysis.After the hemolysis ceased,both the black urine and dysphagia resolved spontaneously.Transient esophageal dysfunction,as a manifestation of gastrointestinal dysmotility,is known to occur in the setting of hemolysis.Paroxysmal nocturnal hemoglobinuria is another recognized cause of massive hemolysis with gastrointestinal dysmotility occurring in25%-35%of patients during a paroxysm.Intravascular hemolysis increases plasma free hemoglobin,which scavenges nitric oxide(NO),an important second messenger for smooth muscle cell relaxation.The decrease in NO can lead to esophageal spasm and resultant dysphagia.In our patient the resolution of hemolysis resulted in resolution of dysphagia.  相似文献   
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目的探索血清标本溶血对部分生化检验结果的影响。方法随机选取50例正常健康人群,提取人群血液作为标本,测定溶血前后总蛋白(TP)、丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、总胆红素(TBIL)、肌酸激酶(CK)、乳酸脱氢酶(LDH),γ-谷氨酰转肽酶(γ-GT)、清蛋白(ALB)、直接胆红素(DBIL)、总胆固醇(TC)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)以及三酰甘油(TG)的变化,分析其差异。结果采血器械质量差以及采血方法不规范是造成标本溶血的主要原因。溶血后AST、ALT、LDH、TP、CK、γ-GT较溶血前升高,差异具有统计学意义(P<0.05)。TBIL、DBIL、TC、TG、ALB、HDL、LDL较溶血前变化不具有统计学意义(P>0.05)。结论标本溶血对于血清AST、ALT、CK、TP、γ-GT、LDH会有干扰作用,在分析测定结果时需要注意标本是否溶血。  相似文献   
10.
Implantable ventricular assist devices (VADs) have proven efficient in advanced heart failure patients as a bridge‐to‐transplant or destination therapy. However, VAD usage often leads to infection, bleeding, and thrombosis, side effects attributable to the damage to blood cells and plasma proteins. Measuring hemolysis alone does not provide sufficient information to understand total blood damage, and research exploring the impact of currently available pumps on a wider range of blood cell types and plasma proteins such as von Willebrand factor (vWF) is required to further our understanding of safer pump design. The extracorporeal CentriMag (Thoratec Corporation, Pleasanton, CA, USA) has a hemolysis profile within published standards of normalized index of hemolysis levels of less than 0.01 g/100 L at 100 mm Hg but the effect on leukocytes, vWF multimers, and platelets is unknown. Here, the CentriMag was tested using bovine blood (n = 15) under constant hemodynamic conditions in comparison with a static control for total blood cell counts, hemolysis, leukocyte death, vWF multimers, microparticles, platelet activation, and apoptosis. The CentriMag decreased the levels of healthy leukocytes (P < 0.006), induced leukocyte microparticles (P < 10?5), and the level of high molecular weight of vWF multimers was significantly reduced in the CentriMag (P < 10?5) all compared with the static treatment after 6 h in vitro testing. Despite the leukocyte damage, microparticle formation, and cleavage of vWF multimers, these results show that the CentriMag is a hemocompatible pump which could be used as a standard in blood damage assays to inform the design of new implantable blood pumps.  相似文献   
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