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131.
132.
Coombs negative autoimmune hemolytic anemia (AIHA) is characterized by laboratory evidence of in vivo hemolysis along with a negative direct antiglobulin test (DAT) performed by conventional tube technique (CTT) in clinically suspected AIHA patients. The sensitive gel test (GT) and flow cytometry (FC) can effectively diagnose such patients where CTT does not detect low level of red cell autoantibodies. We investigated the use of FC in the serological evaluation of CTT DAT negative AIHA and its comparison with GT DAT. Of the 50 patients with suspected AIHA, CTT DAT was negative in 5 patients (Coombs negative AIHA). GT DAT could detect red cell autoantibodies in 4 of these 5 patients. Monospecific GT DAT showed IgG and/or C3d as the responsible autoantibody. FC was considered as reactive when MFI was >3.6 (mean of 20 healthy negative volunteers +2SD). FC was reactive in all five Coombs negative AIHA patients. The mean MFI in five known CTT DAT positive samples taken for comparison was significantly higher compared to 5 DAT negative AIHA (18.3 +/- 7.78 vs. 7.88 +/- 1.35, p < 0.05). There was poor correlation between strength of GT DAT and MFI by FC. We conclude that FC is more sensitive test than the CTT and helps in the serological diagnosis of Coombs negative AIHA. However, in resource poor settings, GT DAT can be a good alternative to FC.  相似文献   
133.
RATIONALE: The model most often used to study the pathogenesis of pulmonary fibroses is the bleomycin (BLM)-induced lung fibrosis model. Several treatments have been efficacious in this model, but not in the clinic. OBJECTIVES: To describe the time course of inflammation and fibrosis in the BLM model and to study the effect of timing of antiinflammatory and antifibrotic treatments on efficacy. METHODS AND MEASUREMENTS: Rats were given single intratracheal injections of BLM on Day 0. At specified time points, 10 rats were killed and their lungs studied for proinflammatory cytokines and for profibrotic growth factor mRNA. After a single intratracheal injection of BLM on Day 0, rats were treated from Day 1 or 10 daily with oral prednisolone (10 mg/kg) or oral imatinib mesylate (50 mg/kg) for 21 d. RESULTS: After BLM administration, the expression of inflammatory cytokines was elevated and returned to background levels at later time points. Profibrotic gene expression peaked between Days 9 and 14 and remained elevated till the end of the experiment, suggesting a "switch" between inflammation and fibrosis in this interval. Antiinflammatory treatment (oral prednisolone) was beneficial when commenced at Day 1, but had no effect if administered from Day 10 onward. However, imatinib mesylate was effective independently of the dosing regime. CONCLUSIONS: The response of the BLM model to antifibrotic or antiinflammatory interventions is critically dependent on timing after the initial injury.  相似文献   
134.
Hypercalcemia associated with transitional cell carcinoma (TCC) is rarely encountered. We report a case of TCC of bladder with documented production of parathyroid hormone related protein (PTHrP). Our patient had a rapidly progressive course and died 2 months after radical cystectomy. Literature suggests that these patients present with advanced stage and carry a poor prognosis. The histopathologic features, treatment and prognosis associated with this rare paraneoplastic syndrome are reviewed.  相似文献   
135.
Autoimmune Lymphoproliferative Syndrome (ALPS) is a rare inherited disorder of disrupted lymphocyte homeostasis characterized by chronic splenomegaly and lymphadenopathy of early onset, hypergammaglobulinemia (Ig G and Ig A), autoimmune phenomena, and expanded populations of TCR-α/β+, CD3+, CD4-, CD8-T cells (Fisher et al. Cell 81:935–946; 1995), called double negative T-cells [(DN) T cells]. We discuss a case of ALPS which showed good response to immunosuppressant drug Mycophenolate-Mofetil in combination with Pyrimethamine/Sulfadoxine.  相似文献   
136.
We conducted a systematic review with meta-analytic elements using publicly available Gene Expression Omnibus (GEO) datasets to determine the role of epigenetic mechanisms in prenatal alcohol exposure (PAE)-induced hypothalamic–pituitary–adrenal (HPA) axis dysfunctions in offspring. Several studies have demonstrated that PAE has long-term consequences on HPA axis functions in offspring. Some studies determined that alcohol-induced epigenetic alterations during fetal development persist in adulthood. However, additional research is needed to understand the major epigenetic events leading to alcohol-induced teratogenesis of the HPA axis. Our network analysis of GEO datasets identified key pathways relevant to alcohol-mediated histone modifications, DNA methylation, and miRNA involvement associated with PAE-induced alterations of the HPA axis. Our analysis indicated that PAE perturbated the epigenetic machinery to activate corticotrophin-releasing hormone, while it suppressed opioid, glucocorticoid receptor, and circadian clock genes. These results help to further our understanding of the epigenetic basis of alcohol's effects on HPA axis development.  相似文献   
137.
Helicobacter pylori infection is strongly associated with low-grade gastric lymphoma, commonly known as mucosa-associated lymphoid tissue (MALT) lymphoma. H. pylori eradication leads to complete remission in 80% of early stage MALT lymphomas. The treatment for early stage H. pylori-negative gastric MALT lymphoma is evolving. Rituximab, a chimeric anti-CD20 antibody, has shown response rates of approximately 50% with minimal toxicity in patients with B-cell non-Hodgkin lymphoma. We describe herein the clinical, endoscopic, and histologic features of a patient with H. pylori-negative gastric MALT lymphoma treated successfully with rituximab.  相似文献   
138.
The presenting symptoms of diabetic ketoacidosis (DKA) include abdominal pain, polyuria and nausea. Diabetes has well known chronic ocular complications like glaucoma, cataracts and retinopathy. We report a case of reversible blindness as a presenting manifestation of DKA that has been reported in literature only 3 times previously. Our objective is to highlight a rare manifestation of a common disease. A 59-year-old male presented with painless vision loss for 3 days and was found to have DKA. The blindness was completely reversed with insulin and bicarbonate treatment. The dramatic presentation and reversibility of blindness was found to be intimately tied with the pH of the patient's serum. Our report gives mechanistic insight for this interesting condition. Clinicians should be aware of reversible blindness as a complication of DKA. Timely correction of the severe acidosis and other metabolic disturbances of DKA may be instrumental in preventing permanent vision loss.  相似文献   
139.
IntroductionLow high-density lipoprotein (HDL-C) and inflammation are risk factors for coronary artery disease (CAD). However, limited data are available determining the role of HDL-C sub-particles HDL2-C and HDL3-C for assessing CAD severity in patients on statin therapy.MethodsBlood samples were obtained prior to cardiac catheterization in 304 consecutive patients with suspected CAD on statin therapy in this sub-analysis of Multi-Analyte, thrombogenic, and Genetic Markers of Atherosclerosis (MAGMA, NCT01276678) study. Detailed lipid profiling and oxidized LDL (ox-LDL) were analyzed. CAD severity was angiographically defined as severe CAD (>75% luminal diameter stenosis [LDS]) and non-severe CAD (≤75% LDS). Multi-regression analysis was performed to test for statistical significance. Receiver operator curve (ROC) analysis was performed to determine cut-point for predicting severe CAD.ResultsPatients with severe CAD had a significantly lower total-HDL-C, lower HDL3-C and higher lipoprotein(a) levels. HDL3-C and lipoprotein(a) cholesterol [Lp(a)-C] retained statistical significance on multiple regression analysis. ROC analysis showed HDL3-C to have a C-statistic of 0.60 (p = 0.003) and Lp(a)-C to have a C-statistic of 0.61 (p = 0.0007). Patients with HDL3-C ≤ 33 mg/dL and Lp(a)-C > 7 mg/dL were found to have significantly elevated ox-LDL levels.ConclusionIn patients on statin therapy, HDL3-C and Lp(a)-C improve prediction of severe CAD compared to a traditional lipid panel. In addition, patients with HDL3-C ≤ 33 mg/dL and Lp(a)-C > 7 mg/dL have greater inflammation marked by ox-LDL. Further studies are needed to evaluate the utility of these novel biomarkers in predicting CAD severity.  相似文献   
140.
OBJECTIVE: Genetic susceptibility to iron loading is an important factor in the development of iron overload in Africans. This suggests that persons of African descent may be at risk to develop iron overload with its attendant complications, but relatively little is known about hepatic iron overload among blacks. The aim of this study was to compare the prevalence, histological features, and clinical correlates of hepatic iron overload in a group of autopsied black and white veterans. METHODS: Hepatic iron concentrations (HIC) were determined on liver tissue from autopsies performed at the John Cochran Veterans Affairs Medical Center during the period 1993 to 1996. Clinical information was obtained from autopsy protocols. Sections from livers in which the HIC exceeded the upper limit of normal were examined histologically. RESULTS: Of 256 specimens, 99 were from blacks (39%), whereas 157 were from whites (61%). Thirty-one blacks (31%) had an elevated HIC versus 44 whites (28%) (ns). In the majority of these cases (18 blacks, 30 whites), the HIC was less than twice the upper limit of normal. Nine of 15 subjects with an HIC greater than twice the upper limit of normal and no evident cause of secondary iron overload were black. CONCLUSIONS: The prevalence of mild-to-moderate hepatic iron overload was similar in this group of black and white veterans. Because of the inherent limitations of autopsy studies, prospective assessment of iron stores in healthy blacks is needed to determine more accurately the prevalence and clinical significance of iron overload in this population.  相似文献   
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