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951.
952.
Nitrogen-doped ZnO nanorod arrays (N:ZnO NRAs) were fabricated by hydrothermal synthesis using a zinc–ammine complex solution, followed by annealing at elevated temperatures under ambient conditions. After annealing at 400 °C for 1 h, Raman spectra indicated that nitrogen was incorporated in the ZnO crystal structure. NH3-ligands in the zinc–ammine complex precursor were incorporated in ZnO crystals during hydrothermal crystal growth and were then ruptured during annealing. Photoluminescence spectra indicated that during post-annealing, the nitrogen was incorporated into the oxygen site, which created accompanying defects such as oxygen vacancies and/or interstitial oxygen. The absorption edge in diffuse-reflectance UV-visible spectra revealed visible absorption after post-annealing. In addition, the N:ZnO NRAs generated strong visible-light-induced photocurrents. Nitrogen doping caused a decline in carrier density, as confirmed by an electrochemical Mott–Schottky plot. These results suggest that this cost-effective fabrication has many potential applications such as solar-induced water splitting.

Nitrogen-doped ZnO nanorod arrays were fabricated by hydrothermal synthesis using a zinc–ammine complex solution, followed by annealing under ambient conditions.  相似文献   
953.
We report 3 cases of locoregional failure or remnant esophageal squamous cell carcinoma after chemoradiotherapy that were successfully treated by argon plasma coagulation (APC) as a salvage treatment. Ablation was performed using argon plasma coagulation APC300 (ERBE). A power setting of 60W and an argon gas flow of 1.8L/min was used. APC is able to be repeated multiply without adverse reaction, and is an effective treatment to control the tumor growth.  相似文献   
954.
Aim: Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signalling, is a novel therapeutic target for type 2 diabetes mellitus. We evaluated in vitro and in vivo the pharmacological profiles of a new PTP1B inhibitor, JTT‐551: monosodium ({[5‐(1,1‐dimethylethyl)thiazol‐2‐yl]methyl} {[(4‐{4‐[4‐(1‐propylbutyl)phenoxy]methyl}phenyl)thiazol‐2‐yl]methyl}amino)acetate. Methods: PTP1B inhibitory activity and the inhibition mode were assayed with p‐nitrophenyl phosphate as a substrate, and the selectivity of JTT‐551 against other PTPs, including T‐cell protein tyrosine phosphatase (TCPTP), CD45 protein tyrosine phosphatase (CD45) and leucocyte common antigen‐related protein tyrosine phosphatase (LAR), was evaluated. Glucose uptake with JTT‐551 treatment was evaluated in L6 rat skeletal myoblasts (L6 cells). In the in vivo study, we investigated the effects on insulin receptor (IR) phosphorylation and blood chemical parameters with JTT‐551 administration in ob/ob mice and db/db mice. Results: JTT‐551 showed an inhibitory effect on PTP1B with a Ki value of 0.22 µM, and a mixed‐type inhibition mode. Ki values of TCPTP, CD45 and LAR were 9.3, 30 or higher and 30 or higher µM, respectively, and JTT‐551 exhibited clear selectivity against the other PTPs. Moreover, JTT‐551 increased the insulin‐stimulated glucose uptake in L6 cells. A single administration of JTT‐551 in ob/ob mice enhanced the IR phosphorylation of liver and reduced the glucose level. In db/db mice, chronic administration showed a hypoglycaemic effect without an acceleration of body weight gain. Conclusions: JTT‐551, a newly developed PTP1B inhibitor, improves glucose metabolism by enhancement of insulin signalling and could be useful in the treatment of type 2 diabetes mellitus.  相似文献   
955.

Background  

Abnormalities of cell cycle regulators are common features in human cancers, and several of these factors are associated with the early development of gastric cancers. However, recent studies have shown that gastric cancer tumorigenesis was characterized by mucin expression. Thus, expression patterns of cell cycle-related proteins were investigated in the early phase of differentiated-type gastric cancers to ascertain any mechanistic relationships with mucin phenotypes.  相似文献   
956.
Fibroblast growth factor 2 (FGF‐2) is a potent mitogen for mesenchymal cells, and a local application of recombinant human FGF‐2 (rhFGF‐2) in a gelatin hydrogel has been reported to accelerate bone union in our animal studies and preparatory dose‐escalation trial on patients with surgical osteotomy. We have performed a randomized, double‐blind, placebo‐controlled trial in which patients with fresh tibial shaft fractures of transverse or short oblique type were randomly assigned to three groups receiving a single injection of the gelatin hydrogel containing either placebo or 0.8 mg (low‐dosage group) or 2.4 mg (high‐dosage group) of rhFGF‐2 into the fracture gap at the end of an intramedullary nailing surgery. Of 194 consecutive patients over 2 years, 85 met the eligibility criteria, and 70 (24 in the placebo group and 23 each in low‐ and high‐dosage groups) completed the 24‐week study. The cumulative percentages of patients with radiographic bone union were higher in the rhFGF‐2‐treated groups (p = .031 and .009 in low‐ and high‐dosage group, respectively) compared with the placebo group, although there was no significant difference between low‐ and high‐dosage groups (p = .776). At 24 weeks, 4, 1, and 0 patients in the placebo, low‐dosage, and high‐dosage groups, respectively, continued to show delayed union. No patient underwent a secondary intervention, and the time to full weight bearing without pain was not significantly different among the three groups (p = .567). There also was no significant difference in the profiles of adverse events among the groups. In conclusion, a local application of the rhFGF‐2 hydrogel accelerated healing of tibial shaft fractures with a safety profile. © 2010 American Society for Bone and Mineral Research.  相似文献   
957.
Shibasaki S, Taniguchi M, Shimamura T, Suzuki T, Yamashita K, Wakayama K, Hirokata G, Ohta M, Kamiyama T, Matsushita M, Furukawa H, Todo S. Risk factors for portal vein complications in pediatric living donor liver transplantation.
Clin Transplant 2010: 24: 550–556.
© 2009 John Wiley & Sons A/S. Abstract: Background: Portal vein (PV) complications in pediatric living donor liver transplantation (LDLT) are often asymptomatic in the early stages after transplantation and can be serious enough to lead to graft failure. There have been few reports on risk factors for PV complications in LDLT. The aim of this study is to investigate the influence of hepatic inflow upon PV complications and to predict patients at risk for these complications. Material/method: From 1997 to 2008, 46 pediatric patients underwent LDLT at our center. Portal venous and hepatic arterial flows and PV diameter were analyzed. Results: PV complications were identified in seven patients (15.2%) and occurred at a younger age and lower weight. As a result of appropriate treatment, none of the patients suffered graft failure. Analysis of the 46 patients and 27 patients under two yr of age indentified smaller PV diameter in recipient and larger discrepancy of PV diameter as risk factors. Portal venous flow tended to be low, in contrast to hepatic arterial flow, which tended to be high. Conclusion: PV size strongly influences PV complications. Other factors such as younger age, low portal venous flow, and high hepatic arterial flow may be risk factors for PV complications.  相似文献   
958.
The aim of our study was to clarify the association between immunoglobulin G(IgG) subclasses and the complement pathway in patients with idiopathic membranous nephropathy (MN). Immunofluorescence (IF) was performed in 16 MN patients and 20 controls using antibodies against IgG, IgA, IgM, C1q, C3c, C4d, IgG1, IgG2, IgG3, IgG4, mannose binding lectin (MBL), C4-binding protein (C4-bp), factor B, C5b-9, and CD59. MN was classified into two types, segmental MN (S-MN; six patients) and global MN (G-MN; ten patients), according to the distribution of IgG deposits along the glomerular capillary wall. No deposition of any antibody was found in the controls. IF revealed IgG1, IgG3, C1q, C3c, C4d, C4-bp, C5b-9, and CD59 deposits in patients with S-MN, whereas IgG1, IgG2, IgG3, IgG4, C3c, C4d, MBL, factor B, C4-bp, C5b-9, and CD59 deposits were detected in those with G-MN. There was a higher deposition of IG1, IgG2, and IgG4 in patients with G-MN than in those with S-MN, whereas the intensity of C1q deposits was higher in S-MN than in G-MN patients. In contrast, the intensity of factor B and MBL was higher in G-MN than in S-MN patients. This is the first report of S-MN patients showing complement activation of the classical pathway associated with IgG1 and IgG3 and G-MN patients showing complement activation of both the alternative and lectin pathways associated with IgG2 and IgG4.  相似文献   
959.

Background/purpose

Alveolar echinococcosis of the liver (AEL) is a zoonosis that is distributed in cold regions of the northern hemisphere. The disease is mostly found in adults and rarely in pediatric patients because it tends to be slow growing.

Patients and methods

Ten Japanese pediatric patients (under 15 years old) with AEL have been operated on in Hokkaido University Hospital from January 1936 to June 2008. We examined these children and revealed the characteristics of AEL.

Results

The patients included three males and seven females whose mean age was 10.9 years old, ranging from 7 to 15. The length of follow-up was from 3 months to 33 years (median 19 years). Six cases were picked up by mass screening; nine cases who underwent hepatectomy are still alive and one case whose tumors were unresectable died of liver failure.

Conclusion

Our cases indicate that some AEL pediatric patients advanced rapidly, so early detection is imperative. Thus, screening examinations are essential for children in contaminated areas and, if a liver tumor is found on a screening examination and diagnosed as AEL, complete radical resection should be performed.  相似文献   
960.
Objective: Fahr disease (FD) is a rare neurological and psychiatric disorder. The disease is classified by intracranial calcification of the basal ganglia with the globus pallidus region being particularly affected. We examined a young woman with visual hallucinations, delusions of persecution and a history of performing arson with possible third‐generation FD. Method: Case report of third‐generation FD. Results: A 23‐year‐old woman was arrested for two arsons: i) The patient exhibited progressive psychotic symptoms, including visual hallucinations, delusion of injury, irritability, lability of mood, mental retardation and visual disorders and ii) Computed tomography (CT) imaging demonstrated bilateral calcifications of the basal ganglia (globus pallidus) in the patient, her mother and her grandmother. Conclusion: We found a family with a three‐generation history of FD who exhibited calcification in the brain and mental retardation. Compared to her mother, the patient described here displayed anticipation of disease onset.  相似文献   
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