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1.
A delayed haemolytic transfusion reaction (DHTR) encompasses a positive direct antiglobulin test (DAT) developed anytime between 24 hours to 28 days after cessation of transfusion, a positive eluate or a newly identified alloantibody in the plasma or serum along with features of haemolysis in the patient. Routinely, it is expected that with the transfusion of one unit of packed red cells in a patient of average height and weight, the haemoglobin level and hematocrit increase by 1 g/dL and 3% respectively. However, in a patient with DHTR, an inadequate rise of post-transfusion haemoglobin (< 1 g/dL) or rapid fall in haemoglobin back to pre-transfusion levels is observed. Kidd antibodies are particularly known to cause DHTR, maybe alone or in unison with other antibodies. Detection of these alloantibodies is consequential in providing good transfusion support to these patients. These events may be difficult to detect as they may present as varied clinical features or immunological nuisances. In this case series, we have presented three cases of DHTR with special emphasis on their clinical presentations, immunohaematological evaluations, laboratory parameters and the role of proper transfusion support in these patients to avoid further complications.  相似文献   
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Blood transfusion is an integral component of the health Service system and it becomes imperative that its benefits, risks as well as prospective and viable alternatives of this common medical intervention are explained explicitly to the patients. Appropriate compliance to bedside blood transfusion practices can also help in avoiding adverse transfusion outcomes. At the same time, it is also crucial to document a patient's valid consent based on their decision after evaluation of the risk to benefit ratio. This audit aims to assess the compliance and adherence to bedside blood transfusion practices in a tertiary care hospital and role of Continuous Medical education (CME) on it. The study involved collection of data for blood transfusion services and practices in two periods, for adults and children, who received transfusion from the month of June 2021 to October 2021 and a re-audit beginning from November 2021 to February 2022 following few CMEs in between involving doctors and nurses. A total of 3240 transfusion procedures were assessed in this duration. In them 1500 (46.3%) took place before CME and remaining 1740 (53.7%) procedures took place after CME. There were statistically significant differences between pre-CME and post-CME bedside transfusion practices. During CME/training session, pre-training and post training knowledge has been evaluated by test which also showed statistically significant difference in knowledge of transfusion medicine & bedside transfusion practices. Our study recommends that there is a need of frequent audit on bedside transfusion practices to check the quality and standards associated with it and also points out the need of continuous medical education on this issue.  相似文献   
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Dynamic monitoring ABO chimera including erythroid ABO antigen and anti-A/B is crucial to not only assess the status of erythroid engraftment but also achieve personalized safety transfusion in patients post ABO incompatible hematopoietic stem cell transplantation. Transfusion support for ABO incompatible (ABOi) HSCT patients after achieved complete alteration to donor origin still remains cautious because the instant hematopoietic status on these transplant patients possibly returned to patient origin derived from early disease relapse and graft loss or failure. We reported that reemergent anti-B in a female patients (donor/patient: B/O) at the early phase after achievement complete donor type were not effectively found from partial automatic ABO blood grouping systems, which directly resulted in differential judgement of transplantation stage for about 15 days and disturbed the optimal recommendation on transfusion support. Meanwhile, the solely alteration of ABO chimera was found and earlier than changes of other markers such as MRD diagnosis, chimerism analysis by STR-PCR and sex chromosome assays, which can be an available predictors for bad transplant outcomes such as graft failure.  相似文献   
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Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.  相似文献   
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ObjectiveThe aim of this study was to assess the effect of topical tranexamic acid on blood loss and transfusion rates in acetabular fracture surgery.MethodsThe medical records of 61 patients who underwent open reduction and internal fixation for acetabular fracture between 2012 and 2015 were retrospectively reviewed. The patients were divided into two groups: Group I consisted of 31 patients (19 men and 12 women, mean age: 52 ± 19 years) who received intraoperatively a topical tranexamic acid solution of 3 g and Group 2 consisted of 30 control patients (17 men and 13 women, mean age: 48 ± 24 years) who received only 0.9% saline solution. The groups were compared based on their intraoperative blood loss, Postoperative drain output at 24 and 48 h, and postoperative hemoglobin levels, and transfusion rates.ResultsThe mean intraoperative blood loss was 410 ± 100 ml in Group 1, compared to 570 ml ± 160 ml of the control group (p < 0.05). The postoperative drain output after 24 h was 210 ± 70 ml in Group 1 compared to 330 ± 90 ml of the control group (p < 0.05). The drain output at 48 h was (50 ± 20 ml) in group 1 compared to 90 ± 40 ml of the control group (p < 0.05). The transfusion rate was significantly low group 1 (42%) than the control group (97%). Hemoglobin drop was again significantly less in tranexamic acid group (2.1 ± 1.1) than the control group (3.2 ± 1.3). The nadir postoperative hemoglobin was higher in the Group 1 (10.4 ± 1.5) than the control group (9.2 ± 1.3).ConclusionTopical administration of tranexamic acid reduces intraoperative and postoperative blood loss in acetabular fracture surgery, decreasing transfusion rates.Level of EvidenceLevel III, Therapeutic Study.  相似文献   
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Measurement of P-selectin on activated platelets as a means of measuring platelet function utilizing the technology described here has the advantage of not requiring immediate access to specialist equipment and expertise. Blood samples are activated, fixed, stored, and transported to a central laboratory for flow cytometric analysis. Here we have compared P-selectin with other more traditional approaches to measuring platelet function in blood and/or platelet-rich plasma (PRP) from patients with acute coronary syndromes on treatment for at least 1 month with either aspirin and clopidogrel or aspirin with prasugrel. The comparators were light transmission aggregometry (LTA), VerifyNow and Multiplate aggregometry (for determining the effects of aspirin) and LTA, VerifyNow and Multiplate together with the BioCytex VASP phosphorylation assay (for the P2Y12 antagonists). The P-selectin Aspirin Test revealed substantial inhibition of platelet function in all but three of 96 patients receiving aspirin with clopidogrel and in none of 51 patients receiving aspirin and prasugrel. The results were very similar to those obtained using LTA. There was only one patient with high residual platelet aggregation and low P-selectin expression. The same patients identified as “non-responders” to aspirin also presented with the highest residual platelet activity as measured using the VerifyNow system, although not quite as well separated from the other values. With the Multiplate test only one of these patients clearly stood out from the others. The results obtained using the P-selectin P2Y12 Test in 102 patients taking aspirin and clopidogrel were similar to the more traditional approaches in that a wide scatter of results was obtained. Generally, high values seen with the P-selectin P2Y12 Test were also high with the LTA, VerifyNow, Multiplate, and BioCytex VASP P2Y12 Tests. Similarly, low residual platelet function using the P2Y12 test was seen irrespective of the testing procedure used. However, there were differences in some patients. Prasugrel was always more effective than clopidogrel in inhibiting platelet function with none of 56 patients (P-selectin and VerifyNow), only 2 of 56 patients (Multiplate) and only 3 of 56 patients (Biocytex VASP) demonstrating high on-treatment residual platelet reactivity (HRPR) defined using previously published cut-off values. The exception was LTA where there were 11 of 56 patients with HRPR. It remains to be seen which experimental approach provides the most useful information regarding outcomes after adjusting therapies in treated patients.  相似文献   
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