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Background: Patients with heart failure with a preserved ejection fraction (HFPEF) have high N‐terminal pro‐B‐type natriuretic peptide (NT‐pro‐BNP) level and a high ratio of early transmitral inflow to diastolic velocity of the mitral annulus (E/E′) derived from tissue Doppler imaging (TDI). Because left atrial volume indexed to body surface area (LAVI) is believed to reflect chronic diastolic dysfunction, we assessed the ability of LAVI and E/E′ ratio to predict NT‐pro‐BNP level in patients with HFPEF. Methods: One hundred forty‐eight patients with HFPEF (ejection fraction ≥ 50%, NT‐pro‐BNP ≥ 100 pg/ml) underwent conventional echocardiography including LAVI and E/E′ ratio, which were compared with NT‐pro‐BNP level. Results: In the overall patient population, modest correlations were found between NT‐pro‐BNP level and peak systolic TDI (S′) (P = 0.009), LAVI (P = 0.009), and E/E′ ratio (P = 0.017). However, in patients with E/E′ ratio ≥13, LAVI was the most important predictor of NT‐pro‐BNP level (P < 0.001), whereas in those with E/E′ ratio <13 it was S′ (P < 0.001) in multivariate analysis. Conclusion: In patients with HFPEF evidenced by high NT‐pro‐BNP level, LAVI correlates with NT‐pro‐BNP level in the setting of elevated E/E′ ratio. However, in the setting of low E/E′ ratio, LAVI does not seem to be associated with NT‐pro‐BNP level.  相似文献   
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BACKGROUND: Percutaneous coronary intervention (PCI) with drug-eluting stents (DES) may be useful in patients with acute myocardial infarction (AMI), but safety issues still need to be solved. This study was undertaken to investigate the incidence of major adverse cardiac events (MACE) and stent thrombosis in DES-implanted AMI patients in real-life clinical practice. METHODS AND RESULTS: On-line registry of AMI cases at the web site www.kamir.or.kr has been performed in 41 primary PCI centers in Korea and between November 2005 and September 2006, 1,541 surviving patients who had been implanted with either Cypher or Taxus stents were enrolled for analysis during a 6-month clinical follow-up. There were 2 groups: group I [834 patients, 61.9+/-11.9 years: sirolimus-eluting stent (Cypher)], group II [707 patients, 62.9+/-12.0 years: paclitaxel-eluting stent (Taxus)]. At both 1 and 6 months the incidence of MACE was not significantly different between the 2 groups. There were 17 cases of stent thrombosis, but the incidence of stent thrombosis was not significantly different between the 2 groups (group I:II=9 (1.1%):8 (1.1%), p=1.000). The stent type, length, number, lesion complexity and diabetes were not significant for the incidence of MACE or stent thrombosis after adjustment. CONCLUSION: MACE and stent thrombosis rates did not differ between 2 types of DES identified in Korea Acute Myocardial Infarction Registry (KAMIR). DES can be used in patients with AMI with a relatively low 6-month MACE rate.  相似文献   
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The aim of our study was to investigate the feasibility of single-beat prospective electrocardiogram (ECG)-gated cardiac computed tomography (CT) using a 256-detector row wide-volume CT scanner for functional and anatomical evaluation of the aortic valve (AV) and coronary arteries in patients with AV disease. A total of 50 patients who underwent cardiac CT scan with a wide-volume 256-detector row CT scanner for the evaluation of AV and aorta were retrospectively enrolled. Cardiac CT was performed using the prospective ECG-gated acquisition mode, and AV image quality was analyzed using a four-point grading system. Severity of aortic stenosis (AS) and aortic regurgitation (AR) were assessed by CT and correlated to that assessed by transthoracic echocardiography (TTE) based on kappa statistics (κ). Estimated radiation exposure was assessed. Among 50 patients, 44 underwent cardiac CT with single-beat acquisition. The median image quality score of AV was 3.0 on the systolic phase and 4.0 on the diastolic phase. Severity of AS and AR by CT showed moderate agreement with TTE. The mean effective radiation dose was 3.75?±?1.43 mSv for CT angiography. Using 256-detector row wide-volume CT, the single-beat cardiac CT is feasible for evaluation of AV disease and the coronary arteries, with acceptable image quality and a low radiation dose of 3.75 mSv.  相似文献   
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We demonstrate the synthesis of poly(methyl methacrylate) (PMMA) and poly(styrene-b-methyl methacrylate) (P(S-b-MMA)) brushes on crosslinked random copolymer thin films, compositionally varied poly(styrene-r-glycidyl methacrylate) (P(S-r-GMA)), which can be further functionalized with a molecule featuring an initiator group upon crosslinking to form highly stable thin films. With careful optimizations, PMMA brushes were successfully grown from the surfaces of initiator functionalized P(S-r-GMA) via surface-initiated atom transfer radical polymerization. The grafting densities of the PMMA and P(S-b-MMA) brushes were effectively controlled to be in different density regimes by controlling the composition of P(S-r-GMA) and post-crosslinking functionalization methods. Synthesized BCP brushes were stable upon repetitive washing and thermal annealing processes even at high grafting density, highlighting that the outstanding stability of crosslinked P(S-r-GMA) thin films enables close examination of the morphology of thermally annealed P(S-b-MMA) brushes in different grafting density regimes.

Crosslinkable epoxy copolymers enable achieving highly stable P(S-b-MMA) brushes with controlled grafting density for close examination of phase separation behaviors.  相似文献   
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Archives of Pharmacal Research - Sappanchalcone, a bioactive flavonoid isolated from the heartwood of Caesalpinia sappan L. possesses anti-inflammatory effects. We studied the efficacy of...  相似文献   
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BACKGROUND & AIMS: Affected individuals with biallelic MYH mutations are believed to display multiple adenomatous polyps without evidence of vertical transmission. Our goal was to determine the detection rate of germline MYH mutations in a high-risk gastrointestinal cancer clinic population by using polyp number as a selection criterion. METHODS: Patients were screened for the 2 most common MYH mutations: Y165C and G382D. The complete MYH coding region was sequenced in cases with a heterozygous mutation. RESULTS: Among 45 patients with more than 15 adenomatous polyps not diagnosed with familial adenomatous polyposis, 7 (15.6%) had biallelic MYH mutations. When 122 participants from a high-risk gastrointestinal cancer clinic who did not fulfill these criteria were tested, 2 additional patients with biallelic mutations were identified. Both had young-onset colorectal cancer (age, <50 y) with fewer than 15 polyps. Surprisingly, most of the 9 patients with biallelic MYH mutations reported family histories consistent with the hereditary nonpolyposis colorectal cancer syndrome (HNPCC), with 7 cases meeting at least 1 of the Bethesda criteria, 5 cases fulfilling 3 Bethesda criteria, and 2 cases fulfilling the Amsterdam II criteria. CONCLUSIONS: Most individuals with MYH mutations exhibit multiple adenomatous polyps. However, 22% of cases were missed when this was the sole criterion for germline testing. A significant number reported a strong family history of cancer that was consistent with HNPCC. MYH testing thus can be considered for patients who meet clinical criteria for HNPCC in the absence of DNA mismatch repair gene mutations.  相似文献   
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Human herpes simplex virus 1 (HSV-1) encephalitis can be caused by inborn errors of the TLR3 pathway, resulting in impairment of CNS cell-intrinsic antiviral immunity. Deficiencies of the TLR3 pathway impair cell-intrinsic immunity to vesicular stomatitis virus (VSV) and HSV-1 in fibroblasts, and to HSV-1 in cortical but not trigeminal neurons. The underlying molecular mechanism is thought to involve impaired IFN-α/β induction by the TLR3 recognition of dsRNA viral intermediates or by-products. However, we show here that human TLR3 controls constitutive levels of IFNB mRNA and secreted bioactive IFN-β protein, and thereby also controls constitutive mRNA levels for IFN-stimulated genes (ISGs) in fibroblasts. Tlr3–/– mouse embryonic fibroblasts also have lower basal ISG levels. Moreover, human TLR3 controls basal levels of IFN-β secretion and ISG mRNA in induced pluripotent stem cell–derived cortical neurons. Consistently, TLR3-deficient human fibroblasts and cortical neurons are vulnerable not only to both VSV and HSV-1, but also to several other families of viruses. The mechanism by which TLR3 restricts viral growth in human fibroblasts and cortical neurons in vitro and, by inference, by which the human CNS prevents infection by HSV-1 in vivo, is therefore based on the control of early viral infection by basal IFN-β immunity.  相似文献   
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