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131.
Although the alpha+ thalassemias almost certainly confer protection against death from malaria, this has not been formally documented. We have conducted a study involving 655 case patients with rigorously defined severe malaria and 648 controls, frequency matched on area of residence and ethnic group. The prevalence of both heterozygous and homozygous alpha+ thalassemia was reduced in both case patients with severe malaria (adjusted odds ratios [ORs], 0.73 and 0.57; 95% confidence intervals [95% CIs], 0.57-0.94 and 0.40-0.81; P = .013 and P = .002, respectively, compared with controls) and among the subgroup of children who died after admission with severe malaria (OR, 0.60 and 0.37; 95% CI, 0.37-1.00 and 0.16-0.87; P = .05 and P = .02, respectively, compared with surviving case patients). The lowest ORs were seen for the forms of malaria associated with the highest mortality-coma and severe anemia complicated by deep, acidotic breathing. Our study supports the conclusion that both heterozygotes and homozygotes enjoy a selective advantage against death from Plasmodium falciparum malaria.  相似文献   
132.
An NDM-1 carbapenemase-producing Pseudomonas aeruginosa isolate was recovered from a patient hospitalized in France after a previous hospitalization in Serbia. Genetic studies revealed that the blaNDM-1 gene was surrounded by insertion sequence ISAba125 and a truncated bleomycin resistance gene. This blaNDM-1 region was a part of the variable region of a new complex class 1 integron bearing IS common region 1 (ISCR1). The presence of ISPa7 upstream of this integron suggests insertion in a chromosomally located Tn402-like structure.  相似文献   
133.
BackgroundThere are conflicting data on the usefulness of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) in the optimization of therapy for heart failure (HF). Discordant results may be explained by the intra-individual variability of these peptides. This study evaluates the intraindividual variability of BNP and NT-proBNP and the impact of the covariates of age, sex, and renal function.Methods and ResultsStable HF patients attending our unit were included. Blood samples were drawn 1 hour apart on 2 occasions 1 week apart. Forty-five patients were enrolled (69.6 ± 12.1 years, 64% male, 84% systolic HF). Within-hour and within-week intraindividual variability were: 6.9% and 21.1% for NT-proBNP; 14.6% and 28.4% for BNP (P < .01 for within-hour comparison of BNP and NT-proBNP). Reference change values over 1 week for NT-proBNP and BNP were 49.2% and 66.2%, respectively. There were no significant relationships identified between variability and age, gender, or glomerular filtration rate.ConclusionThere is considerable intraindividual variability in these peptides in stable HF patients. Changes of approximately 50% and 66% for NT-proBNP and BNP from week to week are needed to indicate an altered clinical status and caution should be exercised in interpreting serial changes in these peptide levels when monitoring patient responses to treatment or clinical status.  相似文献   
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135.
Rationale:Polycystic liver disease is a rare disease characterized by the growth of numerous cysts in the liver. The liver function remains well preserved, but liver volumes can grow very large, and some patients ultimately need a liver transplantation. Other treatment options are limited and there is an unmet need for new therapeutic options.Patient concerns:We describe a 59-year-old patient with pain in the abdomen, especially when bending forward. Five years ago, she was diagnosed with breast cancer and as an incidental finding a couple of large liver cysts were diagnosed, explaining her abdominal pain.Diagnosis:Polycystic liver disease with several large liver cysts.Interventions:The patient was treated with tamoxifen, an estrogen receptor modulator, as treatment for her hormone receptor positive breast cancer. One of the liver cysts was aspirated.Outcomes:In the 4.6 years after the start of tamoxifen treatment, 20 mg once daily, the volume of her liver cysts decreased remarkably. There was a reduction of combined cyst volume from 311 mL to 22 mL without percutaneous drainage.Lessons:Epidemiological as well as experimental evidence supports a pivotal role for estrogens as a driver for growth of polycystic livers. Estrogen antagonism has often been proposed as a therapeutic target, but supporting evidence is lacking in the literature. We hypothesize that the decrease in cyst size in this patient was caused by tamoxifen therapy, suggesting an in vivo antagonistic effect on cystic cholangiocytes. This is an important finding because tamoxifen could be a promising new treatment option for polycystic liver disease.  相似文献   
136.
The risk of venous thromboembolism (VTE) is higher in myeloma patients receiving immunomodulatory compounds. A VTE prophylaxis using low-molecular-weight heparin or aspirin is therefore proposed. Apixaban is an oral direct anti-Xa. Several studies have shown the efficacy and safety of apixaban in VTE prophylaxis compared to enoxaparin. The objective of this prospective phase 2 pilot study was to assess the risk of VTE and bleeding in patients with myeloma treated with immunomodulatory compounds lenalidomide (len) or thalidomide (thal), using apixaban in a preventive scheme. Myeloma patients requiring Melphalan-Prednisone-Thalidomide in the first line, or Lenalidomide-Dexamethasone in the relapse setting received apixaban, 2.5 mg x 2/day for 6 months. Venous (pulmonary embolism—PE, or symptomatic proximal or distal deep vein thrombosis—DVT, or all proximal asymptomatic events detected by systematic proximal bilateral compression ultrasound) or arterial thrombotic events, and bleeding events (ISTH 2005) were registered. One hundred and four patients were enrolled (mean age 69.8 ± 7.8 years), 11 in first line and 93 in relapse. Two venous thrombotic events were observed, for example, an asymptomatic proximal DVT and a symptomatic distal DVT, in the context of apixaban stopped 14 days before, due to lenalidomide-induced thrombocytopenia. No PE or arterial cardiovascular events were reported. Only one major and 11 CRNM hemorrhages were reported. These data must now be confirmed on a randomized large study.  相似文献   
137.
Objective To assess the feasibility and safety of remifentanil-based sedation during noninvasive ventilation (NIV) in patients with NIV failure. Design and setting Prospective clinical investigation in a 16-bed intensive care unit of a university hospital in France. Patients Thirteen patients in NIV failure due to discomfort and/or refusal to continue this ventilatory support: 10 with acute respiratory failure and 3 with acute hypercapnic respiratory failure. Intervention Patients were administered methylene blue and were sedated (Ramsay scale 2–3) by a continuous perfusion of remifentanil during NIV. Cardiorespiratory and ventilatory parameters, blood gas analysis, and adverse events were prospectively recorded. Measurements and results The 13 patients received a total of 125 NIV sessions, totaling 1200 h, of NIV under remifentanil-based sedation (mean remifentanil dose 0.1 ± 0.03 μg/kg per minute). Three patients also required propofol. PaO2/FIO2 ratio increased from 134 ± 69 to 187 ± 43 mmHg after 1 h. In patients with acute respiratory failure respiratory rate decreased from 34 ± 12 per minute before remifentanil to 25 ± 4 per minute after 1 h. In the three patients with acute hypercapnic respiratory failure PaCO2 decreased from 69 ± 7 to 42 ± 5 mmHg. Four patients required endotracheal intubation without aspiration pneumonia. Twelve of the 13 patients left the ICU. Conclusion This pilot study shows that remifentanil-based sedation is safe and effective in the treatment of NIV failure due to low tolerance.  相似文献   
138.
Camelpox virus (CMLV) is the closest known virus to variola virus. Here we report on the anti-CMLV activities of several acyclic nucleoside phosphonates (ANPs) related to cidofovir [(S)-1-(3-hydroxy-2-phosphonomethoxypropyl)cytosine (HPMPC; Vistide)] against two CMLV strains, CML1 and CML14. Cytopathic effect (CPE) reduction assays performed with human embryonic lung fibroblast monolayers revealed the selectivities of the first two classes of ANPs (cHPMPA, HPMPDAP, and HPMPO-DAPy) and of the hexadecyloxyethyl ester of 1-{[(5S)-2-hydroxy-2-oxido-1,4,2-dioxaphosphinan-5-yl]methyl}-5-azacytosine (HDE-cHPMP-5-azaC), belonging to the newly synthesized ANPs, which are HPMP derivatives containing a 5-azacytosine moiety. The inhibitory activities of ANPs against both strains were also confirmed with primary human keratinocyte (PHK) monolayers, despite the higher toxicity of those molecules on growing PHKs. Virus yield assays confirmed the anti-CML1 and anti-CML14 efficacies of the compounds selected for the highest potencies in CPE reduction experiments. Ex vivo studies were performed with a 3-dimensional model of human skin, i.e., organotypic epithelial raft cultures of PHKs. It was ascertained by histological evaluation, as well as by virus yield assays, that CMLV replicated in the human skin equivalent. HPMPC and the newly synthesized ANPs proved to be effective at protecting the epithelial cells against CMLV-induced CPE. Moreover, in contrast to the toxicity on PHK monolayers, signs of toxicity in the differentiated epithelium were seen only at high ANP concentrations. Our results demonstrate that compounds belonging to the newly synthesized ANPs, in addition to cidofovir, represent promising candidates for the treatment of poxvirus infections.  相似文献   
139.
New molecularly targeted therapies for lung cancer   总被引:1,自引:0,他引:1       下载免费PDF全文
Lung cancer is the leading cause of cancer death worldwide. The disease is particularly difficult to detect, and patients often present at an advanced stage. Current treatments have limited effectiveness, and unfortunately, the prognosis remains poor. Recent insights into the molecular pathogenesis and biologic behavior of lung cancer have led to the development of rationally designed methods of early detection, prevention, and treatment of this disease. This article will review the important clinical implications of these advances, with a focus on new molecularly targeted therapies currently in development.  相似文献   
140.
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