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991.
AIDS and Behavior - While pre-exposure prophylaxis (PrEP) is a key HIV prevention tool for adolescents and young adults (AYAs), its initiation and sustained use is shaped by AYAs’ unique...  相似文献   
992.
Pancreatic cancer remains one of medicine’s largest areas of unmet need. With five-year survival rates of < 8%, little improvement has been made in the last 50 years. Typically presenting with advance stage disease, treatment options are limited. To date, surgery remains the only potentially curative option, however, with such late disease presentation, the majority of patients are unresectable. Thus, new therapeutic options and a greater understanding of the complex stromal interactions within the tumour microenvironment are sorely needed to revise the dismal outlook for pancreatic cancer patients. Natural killer (NK) cells are crucial effector units in cancer immunosurveillance. Often used as a prognostic biomarker in a range of malignancies, NK cells have received much attention as an attractive target for immunotherapies, both as cell therapy and as a pharmaceutical target. Despite this interest, the role of NK cells in pancreatic cancer remains poorly defined. Nevertheless, increasing evidence of the importance of NK cells in this dismal prognosis disease is beginning to come to light. Here, we review the role of NK cells in pancreatic cancer, examine the complex interactions of these crucial effector units within pancreatic cancer stroma and shed light on the increasingly attractive use of NK cells as therapy.  相似文献   
993.
Journal of Interventional Cardiac Electrophysiology - Ablation index (AI) is a radiofrequency lesion quality marker. The AI value that allows effective and safe pulmonary vein isolation (PVI) is...  相似文献   
994.
Pituitary - Growth hormone (GH) has an important role in intestinal barrier function, and abnormalities in GH action have been associated with intestinal complications. Yet, the impact of altered...  相似文献   
995.
Diabetic ketoacidosis (DKA) is a common complication of type 1 diabetes mellitus (T1DM). We found that the incidence of DKA was 55.5 per 1000 person-years in US commercially insured patients with T1DM; age-sex-standardized incidence decreased at an average annual rate of 6.1% in 2018–2019 after a steady increase since 2011.  相似文献   
996.
AimsWe sought to characterize the direction and associated factors of eGFR change following diagnosis of youth-onset type 1 and type 2 diabetes.MethodsWe assessed the direction of eGFR change at two visits (mean 6.6 years apart) in SEARCH, a longitudinal cohort study of youth-onset type 1 and type 2 diabetes. We used the CKiDCr-CysC equation to estimate GFR and categorized ‘rising’ and ‘declining’ eGFR as an annual change of ≥3 ml/min/1.73 m2 in either direction. Multivariable logistic regression evaluated factors associated with directional change in eGFR.ResultsEstimated GFR declined in 23.8% and rose in 2.8% of participants with type 1 diabetes (N = 1225; baseline age 11.4 years), and declined in 18.1% and rose in 15.6% of participants with type 2 diabetes (N = 160; baseline age 15.0 years). Factors associated with rising and declining eGFR (versus stable) in both type 1 and type 2 diabetes included sex, age at diagnosis, baseline eGFR and difference in fasting glucose between study visits. Additional factors in type 1 diabetes included time from baseline visit, HbA1c and body mass index.ConclusionsOver the first decade of diabetes, eGFR decline is more common in type 1 diabetes whereas eGFR rise is more common in type 2 diabetes.  相似文献   
997.
Thyroid-associated ophthalmopathy (TAO) is thought to be a T-cell-mediated autoimmune disorder. We sought to characterize abnormalities in the peripheral blood T-cell subsets in patients with TAO, and examine whether the long-acting somatostatin analogue, octreotide-LAR, treatment affects these cells. We analyzed peripheral blood T-cell subsets by flow cytometry in 26 euthyroid patients with moderately severe active TAO and 24 controls. Twenty-five of the patients with TAO were enrolled in a randomized trial to receive either 30 mg of octreotide-LAR (n = 11) or placebo (n = 14) every 4 weeks for 16 weeks; all 25 patients subsequently received octreotide-LAR 30 mg every 4 weeks from week 16 to 32. T-cell subsets were analysed at baseline, week 16, and week 32. At baseline, the relative percentage of CD4+ helper T-cells (p = 0.0003) and the CD4+/CD8+ ratio (p = 0.008) were significantly higher in patients with TAO compared to controls. Patients with TAO had higher na?ve active T cells (CD45RA+, CD45RA+ CD4+) and lower memory T cells (CD45RO+, CD45RO+ CD4+) than controls. At weeks 16 and 32, there were no significant differences in any T-cell subsets between the octreotide-LAR-treated and placebo groups. These results support a role of T cell in the pathogenesis of TAO, and show that octreotide-LAR has no effect on T-cell subsets during 32-weeks of treatment.  相似文献   
998.
OBJECTIVES: To determine whether sex differences in large-artery stiffness contribute to the greater prevalence of systolic hypertension in elderly women than in elderly men. DESIGN: During a single visit arterial stiffness was assessed in the unmedicated state using four parameters. PARTICIPANTS: Three hundred seventy-four women with a mean age+/-standard deviation of 72+/-5 and 296 men aged 71+/-5 participated. SETTING: Hypertensive patients were recruited from general practice as part of the second Australian National Blood Pressure Study in Melbourne, Australia. MEASUREMENTS: Large-artery stiffness was assessed using multiple methodologies, including aortic arch stiffness (beta-index) using M-mode ultrasound and arterial compliance and augmentation index using noninvasive carotid pressure and aortic flow measurements. RESULTS: Women had greater carotid and brachial pulse pressure (PP) than men (P<.001), despite higher mean arterial pressure in men. Mean arterial compliance was lower in women (0.20+/-0.12 vs 0.28+/-0.16 mL/mmHg, P<.001) even after correction for aortic area, and aortic arch stiffness was higher (30+/-36 vs 23+/-22; P<.01). Consistent with both a stiffer proximal circulation and a shorter distance to reflection sites, women had higher augmentation index (38+/-11% vs 29+/-12%, P<.001). In multivariate analysis, sex was an independent determinant of all arterial stiffness indices. CONCLUSION: Independently of known confounders, elderly hypertensive women have stiffer large arteries, greater central wave reflection, and higher PP than elderly men. Stiffer large arteries likely contribute to the greater prevalence of systolic hypertension in elderly women and may partly explain the acceleration in postmenopausal cerebrovascular and cardiac complications.  相似文献   
999.
When normal mice (B6D2F1, WBB6F1- +/+ and WCB6F1- +/+) are exposed to constant hypoxia, they respond with a steady increase of PCV for about 3 weeks. Plasma erythropoietin increases sharply for the first 1 or 2 days only, then falls to control levels, with occasional temporary increases through the next 30–40 days. Genetically anaemic mice (WBB6F1-W/Wv and WCB6F1-Sl/Sld) respond differently. The W/W mice show an increase of PCV, and Sl/Sld mice do not, but both respond with large increases of plasma erythropoietin levels which persist, except for some temporary falls, through 16–40 days. The response to hypoxia of chimeric W/W mice, their anaemia cured by implantation of +/+ marrow cells, resembles that of normal +/+ mice much more than that of anaemic W/W mice. Although normal WBB6F1- +/+ mice recover after 200 R whole-body irradiation at rates similar to those of other normal mice, anaemic WBB6F1-W/W mice show delayed onset of haemopoietic recovery in spite of significant production of erythropoietin. Exogenous erythropoietin injected into mice disappears more slowly from the plasma of anaemic W/W mice than from the plasma of normal +/+ mice, and erythropoietin which has been passed through WBB6F1- +/+ normal mice is not thereby made as effective in anaemic W/W mice as it is in normal mice. These findings are consistent with the view that although both W/W and Sl/Sld anaemic mice can produce large amounts of erythropoietin over prolonged periods, W/W mice remain anaemic because of a genetic defect in RBC precursors, and Sl/Sld mice remain anaemic because of a genetic defect in some part of the internal environment in which the RBC must develop. WBB6F1-W/W anaemic mice, when exposed to hypoxia, excrete erythropoietin in their urine. When these mice have their kidneys removed and they are exposed to hypoxia for a short time there is no significant production of erythropoietin. The suggestion is made that some genetically anaemic large domestic animals, if they could be found, might be useful and needed sources of erythropoietin.  相似文献   
1000.
Activating mutations in the KCNJ11 gene encoding for the Kir6.2 subunit of the beta-cell ATP-sensitive potassium channel have recently been shown to be a common cause of permanent neonatal diabetes. In 80% of probands, these are isolated cases resulting from de novo mutations. We describe a family in which two affected paternal half-siblings were found to be heterozygous for the previously reported R201C mutation. Direct sequencing of leukocyte DNA showed that their clinically unaffected mothers and father were genotypically normal. Quantitative real-time PCR analysis of the father's leukocyte DNA detected no trace of mutant DNA. These results are consistent with the father being a mosaic for the mutation, which is restricted to his germline. This is the first report of germline mosaicism in any form of monogenic diabetes. The high percentage of permanent neonatal diabetes cases due to de novo KCNJ11 mutations suggests that germline mosaicism may be common. The possibility of germline mosaicism should be considered when counseling recurrence risks for the parents of a child with an apparently de novo KCNJ11 activating mutation.  相似文献   
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