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1.
The effect of double-stranded RNA (dsRNA) and bacterial lipopolysaccharideon the sensitivity to tumor necrosis factor (TNF)--medlatedcell death was studied In an In vitro system. Since secretionof TNF- Is a part of the early host response to viral and bacterialinfection, we examined whether mimicking the Infection withviral and bacterial products could affect the response of cellsto TNF-. Incubation of WEHI 164 fibrosarcoma cells with dsRNAor lipopolysaccharide (LPS) significantly increased their sensitivityto TNF--mediated lysis and to TNF-secreting inflammatory T cell-mediatedlysis. Thus, these products could induce Increased sensitivityto TNF- In cells In an inflammatory focus, possibly contributingto selective elimination of Infected but not healthy cells bythis non-specific cytokine. Additionally, our data show thatboth dsRNA and LPS, as well as TNF- Itself, rapidly Induce nuclearfactor-xB (NF-*B), a DNA-bindlng protein Implicated In regulationof gene expression. We suggest that NF-xB could regulate genescrucial for the induction of cell death by TNF-.  相似文献   
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S100B is a calcium binding protein mainly produced by glial cells. Previous studies have shown elevated levels of S100B in patients with schizophrenia. We measured S100B levels in fasting plasma of 39 patients with schizophrenia and 19 adult healthy controls. We used linear regression to compare S100B between patients and controls. In patients only, we also investigated the relationship between S100B levels and psychotic symptoms (assessed by the Positive and Negative Syndrome Scale), and cognitive function (assessed by the NIH Toolbox Cognition Battery), respectively by calculating Pearson’s correlation coefficients. Mean plasma S100B was significantly higher in the patient group than in the control group. There were no significant correlations between plasma S100B and psychotic symptoms or cognition.  相似文献   
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We audited the practice of offering, and the uptake of, an HIV antibody test amongst genitourinary medicine clinic patients in the West Midlands region. There were wide variations in the offering (from 14 to 100%) and uptake (18 to 64%) of the test in the different clinics within the same region.  相似文献   
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Since December 2019, the human populations of the 195 global countries continue experiencing grave health and life threats due to the current COVID-19 pandemic. As a result of the novelty of the pathogen, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), at present there is lack of preventive as well as therapeutic options for treating and managing the infection. The use of ancient immunotherapeutic technique – the convalescent plasma (CP) therapy, may act as an immediate and available option to control the COVID-19 pandemic. This review provides a concept and understanding on the CP therapy, its potential to control SARS-CoV-2 pandemic. The CP therapy might act as an immediate saviour for society from the virus. Although the CP therapy has exert affirmative result against COVID-19 it has not been recommended for long time use in COVID-19 and this review gives support for its possible application.  相似文献   
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Myeloid-derived suppressor cells (MDSCs), one of the major orchestrators of immunosuppressive network are present in the tumor microenvironment suppress antitumor immunity by subverting Th1 response in tumor site and considered as a great obstacle for advancement of different cancer immunotherapeutic protocols. Till date, various pharmacological approaches have been explored to modulate the suppressive functions of MDSCs in vivo. The present study describes our endeavor to explore a possibility of eradicating MDSCs by the application of a copper chelate, namely copper N-(2-hydroxy acetophenone) glycinate (CuNG), previously found to be a potential immunomodulator that can elicit antitumorogenic Th1 response in doxorubicin-resistant EAC (EAC/Dox) bearing mice. Herein, we demonstrated that CuNG treatment could reduce Gr-1+CD11b+ MDSC accumulation in ascitic fluid and spleen of EAC/Dox tumor model. Furthermore, we found that CuNG mediated reduction in MDSCs is associated with induction of Th1 response and reduction in Treg cells. Moreover, we observed that CuNG could deplete MDSCs by inducing Fas-FasL mediated apoptotic cell death where death receptor Fas expression is enhanced in MDSCs and FasL is provided by activated T cells. However, MDSC expansion from bone marrow cells and their differentiation was not affected by CuNG. Altogether, these findings suggest that the immunomodulatory property of CuNG is attributed to, at least in part, by its selective cytotoxic action on MDSCs. So, this preclinical study unveils a new mechanism of regulating MDSC levels in drug-resistant cancer model and holds promise of translating the findings into clinical settings.  相似文献   
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Background

Benign biliary obstruction (BBO) is an important complication in patients with advanced chronic pancreatitis (CP). Its presentation varies from an incidental finding to overt jaundice. Thus it presents certain management issues. The present study was therefore performed to analyze the clinical presentation and management of biliary obstruction in patients with CP.

Methods

Retrospective analysis was performed from a prospectively collected database of 155 CP patients managed at our institute from October 2003 to June 2012.

Results

Among 43 (28 %) CP patients with biliary obstruction, 3 patients had evidence of malignancy on follow-up examination and were excluded from the final analysis. The various presentations include chronic nonprogressive elevation of serum alkaline phosphatase (SAP) (n = 15), a progressive increase in SAP with episodes of jaundice (n = 17), and persistent jaundice (n = 8). Of 15 patients with chronic nonprogressive elevation of SAP, 5 were managed conservatively, and the remaining 10 underwent only a pancreatic drainage procedure. During a median follow-up of 41 months (range 11–90 months), none of the 15 patients developed complications related to biliary obstruction. All patients with progressive increase in SAP levels and persistent jaundice underwent the biliary drainage procedure [choledochojejunostomy (CDJ, n = 20) and choledochoduodenostomy (CDD, n = 3)]. During a median follow-up of 30 months (range 10–89 months), two patients died of unrelated causes and two patients had an asymptomatic elevation of SAP.

Conclusions

BBO is common in patients with CP; however, biliary drainage is not indicated for chronic nonprogressive elevation of SAP. In patients with a progressive increase in SAP or persistent jaundice, both CDJ and CDD provide effective biliary drainage.  相似文献   
10.
Silicene has become a topic of interest nowadays due to its potential application in various electro-mechanical nanodevices. In our previous work on silicene, fracture stresses of single crystal and polycrystalline silicene have been investigated. Existence of defects in the form of cracks reduces the fracture strength of silicene nanosheets to a great extent. In this study, an engineering way has been proposed for improving the fracture stress of silicene nanosheets with a pre-existing crack by incorporating auxiliary cracks symmetrically in a direction perpendicular to the main crack. We call this mechanism the “Failure shielding mechanism”. An extensive molecular dynamics simulation based analysis has been performed to capture the atomic level auxiliary crack-main crack interactions. It is found that the main crack tip stress distribution is significantly changed with the presence of auxiliary cracks for loading along both armchair and zigzag directions. The effects of temperature and the crack propagation speed of silicene have also been studied. Interestingly, in the case of loading along the zigzag direction, SW defect formation is observed at the tip of main crack. This leads to a reduction of the tip stress resulting in a more prominent failure shielding in case of zigzag loading than in armchair loading. Moreover, the position and length of the cracks as well as the loading directions have significant impacts on the tip stress distribution. Finally, this study opens the possibilities of strain engineering for silicene by proposing an engineering way to tailor the fracture strength of silicene.

Inclusion of auxiliary cracks increases the fracture stress of silicene nanosheets with a pre existing crack.  相似文献   
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