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121.
Fucoidans have been extensively studied for their various biological activities but the exact role of fucoidans on the inflammatory processes associated with arthritic disease has not been studied. The effect of the treatment of high, medium and low molecular weight fucoidans (HMWF, MMWF and LMWF, respectively) on the progression of collagen‐induced arthritis (CIA) was tested. A daily oral administration of HMWF enhanced the severity of arthritis, inflammatory responses in the joint cartilage and the levels of collagen‐specific antibodies, while LMWF reduced the severity of arthritis and the levels of Th1‐dependent collagen‐specific IgG2a. Further in vitro analyses, using macrophage cell lines, revealed that the HMWF induced the expression of various inflammatory mediators, and enhanced the cellular migration of macrophages. These stimulatory effects of fucoidan decreased in fucoidans with lower molecular weights and LMWF did not exhibit any pro‐inflammatory effects. Interestingly, the oral administration of HMWF enhanced the production of IFN‐γ, one of the Th1 cytokines, in collagen‐stimulated spleen cells that had been isolated from CIA mice, while LMWF had the opposite effect. These results indicate that HMWF enhances arthritis through enhancing the inflammatory activation of macrophages while LMWF reduces arthritis through the suppression of Th1‐mediated Immune reactions. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
122.
Cancer immuno-gene therapy is an introduction of nucleic acids encoding immunostimulatory proteins, such as cytokine interleukin 12 (IL-12), into somatic cells to stimulate an immune response against a tumor. Various methods can be used for the introduction of nucleic acids into cells; magnetofection involves binding of nucleic acids to magnetic nanoparticles with subsequent exposure to an external magnetic field. Here we show that surface modified superparamagnetic iron oxide nanoparticles (SPIONs) with a combination of polyacrylic acid (PAA) and polyethylenimine (PEI) (SPIONs-PAA-PEI) proved to be safe and effective for magnetofection of cells and tumors in mice. Magnetofection of cells with plasmid DNA encoding reporter gene using SPIONs-PAA-PEI was superior in transfection efficiency to commercially available SPIONs. Magnetofection of murine mammary adenocarcinoma with plasmid DNA encoding IL-12 using SPIONs-PAA-PEI resulted in significant antitumor effect and could be further refined for cancer immuno-gene therapy.  相似文献   
123.
The aim of the present study was to evaluate the expression of standard CD44 (CD44s) in colorectal cancer (CRC), its relationship with clinicopathological characteristics, and its potential prognostic significance. CD44s levels were measured on immunohistochemistry in tumors and surrounding normal mucosa from 74 patients with primary colorectal carcinomas. The patients were followed for a median period of 37 months. Expression of CD44s in primary tumor and surrounding normal mucosa tissues was demonstrated in 100% (74/74) and 37.9% (28/74), respectively. The expression of CD44s in tumors was significantly associated with the depth of invasion ( P  = 0.034) and lymph node involvement ( P  = 0.031). A significant difference was observed between the overall survival and level of tumor CD44s expression, especially for stage IV carcinoma ( P  = 0.038). Multivariate analysis indicated that TNM stage ( P  = 0.020) and tumor CD44s expression ( P  = 0.008) were independent predictors of overall survival in adenocarcinomas. CD44s overexpression may be an independent unfavorable prognostic factor for overall survival in advanced CRC, especially stage IV disease. Further investigation, however, is necessary to assess the biological roles of CD44 in CRC, and validate their possible value as novel therapeutic targets.  相似文献   
124.
Staphylococcus aureus is among the most important human pathogens. It is associated with different infections and is a major cause of skin and soft tissue infections (SSTIs). The aim of our study was to compare S. aureus isolates associated with SSTIs with isolates obtained from healthy carriers in the Central Slovenia region in terms of antimicrobial susceptibility, genetic diversity by clonal complex (CC)/sequence type, spa type, and by toxin gene profiling. In total, 274 S. aureus isolates were collected prospectively by culturing wound samples from 461 SSTI patients and nasal samples from 451 healthy carriers. We have demonstrated high heterogeneity in terms of CCs and spa type in both groups of isolates. The main clone among SSTI strains was Panton–Valentine leukocidin gene (pvl) positive CC121, whereas the main clone among carrier strains was CC45 carrying a large range of toxin genes. The main spa type in both groups was t091. Pvl was more frequently present in SSTI strains (31.2% SSTI vs 3.6% carrier strains) and staphylococcal enterotoxin C was more frequently present in carrier strains (1.6% SSTI vs 17.0% carrier strains). We have also demonstrated that methicillin‐resistant S. aureus was a rare cause (2.8%) of SSTIs in our region.  相似文献   
125.
Antigen-presenting cells (APC) play a pivotal role in the initiation of the T cell-mediated and antigen-specific immune response. The suggested role of endogenous inhibitor cystatin C (CyC) is to modulate cysteine proteases (cathepsins) present in human APC. To test this hypothesis, dendritic cells (DC) were generated in vitro from isolated monocytes, and changes in content, localization, and secretion of CyC and cathepsins S, L, and H (CatS, -L, and -H, repsectively) were followed in response to interleukin-4, enabling monocyte differentiation, and to tumor necrosis factor alpha (TNF-alpha), enabling DC maturation. A large increase in intracellular CyC accompanied the differentiation of monocytes to immature DC, also shown by strong immunolabeling of Golgi in immature DC. On DC maturation, intracellular CyC levels decreased, and CyC was mostly absent from the Golgi. On prolonged incubation of mature DC with TNF-alpha, CyC was found located in the proximity of the plasma membrane, indicating that the transport of CyC from Golgi was not blocked as the result of the arrested exocytosis in mature DC. The secretion of CyC ceased, consistent with the peak of the surface expression of phenotypic markers (CD40, CD54, CD80, CD83, CD86, and major histocompatibility complex class II), characteristic for the mature DC stage, whereas the secretion of cathepsins did not correlate with the maturation stage. The difference in localization of CyC and of CatS, -L, and -H in immature and mature DC shows that the regulatory potential of CyC toward CatS, -L, and -H inside DC is limited. However, these interactions may occur extracellularly in lymph, as suggested by the large excess of CyC over secreted CatS, -L, and -H, and they may facilitate DC migration to lymph nodes.  相似文献   
126.
A nanocomposite of waterborne polyurethane (WPU) was prepared with functionalized graphene sheets (FGSs) which are a new type of nano‐sized conductive filler. The FGS were finely dispersed in a polymer matrix to improve the conductivity of the WPU. Conductivity of about 105 times that of pristine WPU was attained using two parts FGS per 100 parts of the matrix polymer. The FGS reduced the hard segment crystallinity of the WPU, which lowered the modulus of the WPU at room temperature. This modulus reduction became more evident in the temperature region above the glass transition temperature of the hard segment.

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127.

Introduction

Elderly patients are more prone to encounter some adverse factors when they receive chemotherapy compared to younger patients. Addition of rituximab to a reduced dose (RD) of cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) chemotherapy might improve patient outcomes with an improved toxicity profile when provided to elderly patients with diffuse large B-cell lymphoma.

Patients and Methods

A total of 53 patients aged ≥ 65 years with diffuse large B-cell lymphoma diagnosed between August 2012 and December 2014 were enrolled onto this study. RD-R-CHOP regimen consisted of rituximab at 375 mg/m2, cyclophosphamide at 600 mg/m2, doxorubicin at 30 mg/m2, and vincristine at 1 mg on day 1 of each cycle and 40 mg of prednisone on days 1 to 5. Patients received granulocyte colony-stimulating factor if they experienced grade 3/4 neutropenia or febrile neutropenia during any cycle.

Results

The median follow-up duration was 18 months (range, 1-44 months). Complete response and overall response rates were 64.1% and 81.1%, respectively. Three-year event-free and overall survival rates were 45.7% ± 8.4% and 62.7% ± 8.1%, respectively. Grade 3/4 neutropenia occurred in 20 patients (37.7%), while febrile neutropenia occurred in 7 patients (20.7%).

Conclusion

Outcomes of RD-R-CHOP chemotherapy were comparable to those of standard-dose R-CHOP or previous dose-adjusted R-CHOP chemotherapy. In the future, strategies such as tailored therapy based on geriatric assessment results are needed to determine the chemotherapeutic dosage.  相似文献   
128.
129.
Extraneural metastases from primary central nervous system (CNS) tumors are unusual, and glioblastomas and medulloblastomas constitute the majority of these. That oligodendroglioma frequently seeds within the CNS is well known. However, extraneural metastases of anaplastic oligodendroglioma are rare. We report a 50-year-old woman who developed multiple lung and liver metastases 28 months after resection of a temporal lobe anaplastic oligodendroglioma.  相似文献   
130.
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