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991.
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Hyperlipidemia is a highly prevalent risk factor for coronary and cervical atherosclerosis and stroke. However, even in the absence of overt atherosclerosis, hyperlipidemia disrupts endothelial and smooth muscle function. We investigated the impact of hyperlipidemia on resting-brain perfusion, fundamental cerebrovascular reflexes, and dynamic perfusion defect during acute focal ischemia in hyperlipidemic apolipoprotein E knockout mice before the development of flow-limiting atherosclerotic stenoses. Despite elevated blood pressures, absolute resting cerebral blood flow was reduced by 20% in apolipoprotein E knockout compared with wild type when measured by [14C]-iodoamphetamine technique. Noninvasive, high spatiotemporal resolution laser speckle flow imaging revealed that the lower autoregulatory limit was elevated in apolipoprotein E knockout mice (60 vs. 40 mm Hg), and cortical hyperemic responses to hypercapnia and functional activation were attenuated by 30% and 64%, respectively. Distal middle cerebral artery occlusion caused significantly larger perfusion defects and infarct volumes in apolipoprotein E knockout compared with wild type. Cerebrovascular dysfunction showed a direct relationship to the duration of high-fat diet. These data suggest that hyperlipidemia disrupts cerebral blood flow regulation and diminishes collateral perfusion in acute stroke in the absence of hemodynamically significant atherosclerosis.  相似文献   
993.
994.
Targeted resequencing using next-generation sequencing technology is being rapidly applied to the molecular diagnosis of human genetic diseases. The group of muscular dystrophies may be an appropriate candidate for this approach because these diseases exhibit genotype–phenotype heterogeneity. To perform a proof-of-concept study, we selected four patients with congenital muscular dystrophies with defective glycosylation of alpha-dystroglycan. A custom-solution-based target enrichment kit was designed to capture whole-genic regions of the 26 muscular-dystrophy-related genes, including six genes implicated in alpha-dystroglycanopathies. Although approximately 95% of both coding and noncoding regions were covered with at least 15-read depth, parts of the coding exons of FKRP and POMT2 were insufficiently covered. Homozygous and compound heterozygous POMGnT1 mutations were found in two patients. Two novel noncoding variants of FKTN were identified in one patient who had a retrotransposon insertion mutation of FKTN in only one allele. The current targeted resequencing strategy yielded promising results for the extension of this method to other muscular dystrophies. As suboptimal coverage in a small subset of coding regions may affect the sensitivity of the method, complementary Sanger sequencing may be required.  相似文献   
995.
We assemble a film of a phosphocholine-based lipid and a crystalline conjugated polymer using hydrophobic interactions between the alkyl tails of the lipid and alkyl side chains of the polymer, and demonstrated its selective gas adsorption properties and the polymer''s improved light absorption properties. We show that a strong attractive interaction between the polar lipid heads and CO2 was responsible for 6 times more CO2 being adsorbed onto the assembly than N2, and that with repeated CO2 adsorption and vacuuming procedures, the assembly structures of the lipid-polymer assembly were irreversibly changed, as demonstrated by in situ grazing-incidence X-ray diffraction during the gas adsorption and desorption. Despite the disruption of the lipid structure caused by adsorbed polar gas molecules on polar head groups, gas adsorption could promote orderly alkyl chain packing by inducing compressive strain, resulting in enhanced electron delocalization of conjugated backbones and bathochromic light absorption. The findings suggest that merging the structures of the crystalline functional polymer and lipid bilayer is a viable option for solar energy-converting systems that use conjugated polymers as a light harvester and the polar heads as CO2-capturing sites.

Assembly films of a phosphocholine-based lipid and a crystalline conjugated polymer had significant CO2 selective adsorption and light absorption due to the attractive interaction of CO2 with exposed polar lipid heads and enhanced morphologies.  相似文献   
996.
OBJECTIVE: The coxsackie and adenovirus receptor (CAR) and the decay-accelerating factor (DAF) are receptors for coxsackievirus B3 (CVB3), which is known as the major cause of human viral myocarditis. We investigated the potential for therapeutic use of soluble virus receptor fusion proteins. METHODS: We designed and generated a novel virus receptor trap (hCAR-hDAF:Fc) consisting of both CVB3 receptors and the Fc portion of human IgG1 and evaluated its antiviral effects in experimental CVB3 myocarditis. RESULTS: Among four soluble virus receptor fusion proteins (hCAR:Fc, hDAF:Fc, hCAR-hDAF:Fc and hDAF-hCAR:Fc), hCAR:Fc and hCAR-hDAF:Fc in the supernatant of transfected cells neutralized echovirus, adenovirus, and various serotypes of CVB in a dose-dependent manner. Both soluble viral receptor proteins bound to the VP0 and VP1 capsid proteins of CVB3. The in vivo efficacy of viral receptor proteins was evaluated by intramuscular injection of plasmid (hCAR:Fc or hCAR-hDAF:Fc) followed by electroporation in a murine model of CVB3 myocarditis. Serum levels of the virus receptor proteins increased relative to baseline values from day 3 and peaked on day 14 at 12.9-fold for hCAR:Fc and 7.1-fold for hCAR-hDAF:Fc. The 3-week survival rate was significantly higher in hCAR-hDAF:Fc-treated mice (61%) than in hCAR:Fc-treated mice (29%) and in controls (15%; p<0.05). Myocardial inflammation, fibrosis, and myocardial virus titers were all significantly reduced in the hCAR:Fc and hCAR-hDAF:Fc groups compared to the controls. CONCLUSION: Our soluble virus receptor trap, hCAR-hDAF:Fc, attenuated viral infection, myocardial inflammation, and fibrosis, resulting in higher survival rates in mice with coxsackieviral myocarditis. Furthermore, it consists exclusively of human components, and we demonstrated that this soluble virus receptor trap may be used as a potential candidate for a novel therapeutic agent for the treatment of acute viral myocarditis during the viremic phase.  相似文献   
997.
Several studies have suggested the possibility of a prognostic relationship between Epstein–Barr virus (EBV) and diffuse large B‐cell lymphoma (DLBCL). The clinical outcome of EBV‐associated DLBCL is not clear, especially since the introduction of rituximab. We retrospectively analyzed 222 elderly patients (≥50 years) with DLBCL who received R‐CHOP chemotherapy and evaluated the state of EBV‐encoded RNA‐1 (EBER). Eighteen cases (8.1%) were EBER‐positive (+). After a median of six cycles of R‐CHOP chemotherapy, the response rate (≥partial response) was 72.2% (13/18) in the EBV (+) patients and 90.2% (184/204) in the EBV (?) DLBCL patients (P = 0.021). Four of 18 (22.2%) EBV (+) DLBCL patients received two or fewer cycles of R‐CHOP chemotherapy. R‐CHOP chemotherapy was also interrupted early more frequently compared with the EBV (?) group (2.5%) (P = 0.00). At a median follow‐up of 32.8 months, there was no significant difference in the overall survival between the groups (P = 0.627). The EBV (+) DLBCL patients with early interruption of R‐CHOP chemotherapy showed a trend toward a high EBV‐DNA titer (≥1,000 copies/mL) (P = 0.091). The results suggest that the EBV (+) tumoral status of elderly DLBCL patients who undergo R‐CHOP chemotherapy does not predict their survival but that their EBV status may contribute to the early interruption of R‐CHOP chemotherapy. Am. J. Hematol. 88:774–779, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
998.
Primary malignant melanoma of the esophagus (PMME) is a rare disease. Here, we describe a case of PMME that was identified at a very early stage. A 65-year-old man underwent upper gastrointestinal endoscopy and was found to have a pigmented small nodule in the lower esophagus. A biopsy was taken and diagnosed as malignant melanoma, so the patient then received radical esophagectomy. Histopathological examination showed atypical cell infiltrate in the lamina propria mucosae without lymph-node metastasis. The patient was followed up without adjuvant chemotherapy. Multiple liver and lung metastases were found at 19 months after surgery, and the patient received DAV-feron (DTIC/ACNU/VCR/IFN-β) therapy. However, the tumors progressed and the patient died of the disease at 27 months after surgery. More detailed surveys after surgery with diagnostic imaging and tumor markers are recommended. Adjuvant chemotherapy is worth considering, even in patients with early-stage PMME.  相似文献   
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