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51.
Interferon‐induced transmembrane protein 3 (IFITM3) ?plays a crucial role in the antiviral responses of Type I interferons (IFNs). The role of IFITM3 in the central nervous system (CNS) is, however, largely unknown, despite the fact that its expression is increased in the brains of patients with neurologic and neuropsychiatric diseases. Here, we show the role of IFITM3 in long‐lasting neuronal impairments in mice following polyriboinosinic‐polyribocytidylic acid (polyI:C, a synthetic double‐stranded RNA)‐induced immune challenge during the early stages of development. We found that the induction of IFITM3 expression in the brain of mice treated with polyI:C was observed only in astrocytes. Cultured astrocytes were activated by polyI:C treatment, leading to an increase in the mRNA levels of inflammatory cytokines as well as Ifitm3. When cultured neurons were treated with the conditioned medium of polyI:C‐treated astrocytes (polyI:C‐ACM), neurite development was impaired. These polyI:C‐ACM‐induced neurodevelopmental abnormalities were alleviated by ifitm3?/? astrocyte‐conditioned medium. Furthermore, decreases of MAP2 expression, spine density, and dendrite complexity in the frontal cortex as well as memory impairment were evident in polyI:C‐treated wild‐type mice, but such neuronal impairments were not observed in ifitm3?/? mice. We also found that IFITM3 proteins were localized to the early endosomes of astrocytes following polyI:C treatment and reduced endocytic activity. These findings suggest that the induction of IFITM3 expression in astrocytes by the activation of the innate immune system during the early stages of development has non‐cell autonomous effects that affect subsequent neurodevelopment, leading to neuropathological impairments and brain dysfunction, by impairing endocytosis in astrocytes. GLIA 2013  相似文献   
52.
Forensic Toxicology - This case report describes the purposeful forensic detection of both the muscle relaxant rocuronium and the reversal agent sugammadex in the blood of a patient who died 8 days...  相似文献   
53.
To establish an effective cancer immunotherapy, it is crucial that cancer cells present a cancer‐specific antigen in a hypoxic area, a hallmark of the tumor microenvironment. Here, we show the impact of hypoxia on MHC class I antigen presentation in vitro and in vivo in murine tumors. Activation of antigen‐specific CTLs by tumor cells that had been pre‐incubated under a condition of hypoxia was enhanced compared with that by tumor cells pre‐incubated under a condition of normoxia. Cell surface expression of MHC class I‐peptide complex on the tumor cells was increased under a condition of hypoxia, thereby leading to higher susceptibility to specific CTLs. We show that the hypoxia‐inducible ER‐resident oxidase ERO1‐α plays an important role in the hypoxia‐induced augmentation of MHC class I‐peptide complex expression. ERO1‐α facilitated oxidative folding of MHC class I heavy chains, thereby resulting in the augmentation of cell surface expression of MHC class I‐peptide complex under hypoxic conditions. These results suggest that since the expression of MHC class I‐peptide complex is augmented in a hypoxic tumor microenvironment, strategies for inhibiting the function of regulatory T cells and myeloid‐derived suppressor cells and/or immunotherapy with immune checkpoint inhibitors are promising for improving cancer immunotherapy.  相似文献   
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A very rare case of adenomyoma of the common hepatic duct is described. A 54-year-old woman was admitted with impending obstructive jaundice secondary to adenomyoma of the common hepatic duct. Our impression, formulated from her clinical presentation, endoscopic investigations, and biochemical and radiological findings, was a cancer of the proximal common hepatic duct. The patient was treated successfully by combination surgical resection and hepaticojejunostomy. Despite our obtaining an intraoperative frozen section, final histological examination was required to confirm the diagnosis. The patient remains well 16 months postoperatively. A survey of the world literature revealed that this is the second report of adenomyoma occurring in the common hepatic duct.  相似文献   
57.
Platelet activation and the formation of platelet microaggregates in coronary vessels play pivotal roles in myocardial ischemia and reperfusion injury. The Fc receptor gamma-chain (FcR gamma) is coexpressed with glycoprotein (GP) VI, forming a platelet collagen receptor, and the activation of platelets by collagen is closely coupled with tyrosine phosphorylation of the FcRgamma. To examine the functional significance of platelet FcR gamma/GPVI complex in the early phase of myocardial ischemia and reperfusion injury in mice, we performed coronary occlusion and reperfusion experiments using wild type mice and FcRgamma-deficient (FcRgamma(-/-)) mice that lack GPVI. The infarct size was significantly smaller in FcRgamma(-/-) mice subjected to occlusion and reperfusion of the coronary artery than in control FcR gamma(+/+) mice. Twenty-four hours after the reperfusion, electron microscopy of the injured tissue showed substantially more platelet aggregation and occlusive platelet microthrombi in the capillaries of the damaged areas of the wild type mice than in those of the FcR gamma(-/-) mice. Platelet Syk was scarcely activated in the FcR gamma(-/-) mice after myocardial ischemia and reperfusion, but significantly activated in the FcR gamma(+/+) mice. CD11b expression on neutrophils was elevated after myocardial ischemia and reperfusion in both mouse groups, whereas myeloperoxidase activity in the injured areas was significantly lower in the FcRgamma(-/-) mice than in the FcRgamma(+/+) mice. These results suggest that the collagen-induced activation of platelets through the FcR gamma plays a pivotal role in the extension of myocardial ischemia-reperfusion injury. FcRgamma and GPVI may be important therapeutic targets for myocardial ischemia-reperfusion injury.  相似文献   
58.

Background

IgG4 production is regulated by type 2 (IL-4 and IL-13) and regulatory (IL-10) cytokines involved in the pathophysiology of chronic rhinosinusitis (CRS). We sought to determine the pathophysiological characteristics of IgG4-positive cells in sinonasal tissues in CRS, especially eosinophilic CRS (ECRS).

Methods

IgG4-positive cells in uncinate tissues (UT) and nasal polyps (NP) were examined by immunohistochemistry. Associations between the number of IgG4-positive cells and clinicopathological factors were analyzed. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of IgG4-positive cells in tissue that can predict the post-operative course.

Results

IgG4 was mainly expressed in infiltrating plasma and plasmacytoid cells, and the number of IgG4-positive cells was significantly higher in NP, especially those from severe ECRS patients, than in UT. In CRS patients, the number of IgG4-positive cells significantly and positively correlated with blood and tissue eosinophilia, radiological severity, and serum level of total IgE. The number of infiltrating IgG4-positive cells was significantly higher in patients with a poor post-operative course (sustained sinus shadow 6 months after surgery) than in those with a good one. The number of IgG4-positive cells in NP could discriminate patients with a good or a poor post-operative course (area under the curve: 0.769). Also, 73.3% sensitivity and 82.5% specificity were achieved when the cut-off value was set at 17 cells/high-power field.

Conclusions

Our results suggest that the local expression of IgG4 on cells may be used as a biomarker that reflects the pathophysiology of CRS, including the post-operative course.  相似文献   
59.

Background

IL-10 is a major anti-inflammatory cytokine that prevents inflammation-mediated tissue damage. We characterized the production of IL-10 by sinonasal tissue cells following exposure to Staphylococcus aureus enterotoxin B (SEB), which elicits cellular responses and is associated with the pathogenesis of eosinophilic chronic rhinosinusitis (ECRS).

Methods

Dispersed nasal polyp (NP) cells and uncinate tissue (UT) cells were prepared from patients with CRS with and without NP, respectively. Cells were incubated with SEB, and then the levels of IL-10 in the cell supernatants were determined. The effect of neutralizing IL-10 on SEB-induced IL-5, IL-13, IFN-γ, and IL-17A production was examined. Expression of IL-10 in NPs was also determined.

Results

IL-10 was expressed in infiltrating inflammatory cells in NPs. NP cells, especially non-adherent NP cells, produced substantial amounts of IL-10 in response to SEB. Although baseline production of IL-10 was significantly higher in NP cells than UT cells, the degree of IL-10 response to SEB was not significantly different between the cell types. The degree of IL-10 production was negatively correlated with the degree of eosinophilia both in tissues and peripheral blood whereas positively correlated with the 1-s forced expiratory volume/forced vital capacity ratio. Patients with severe ECRS displayed a significant decrease in IL-10 production compared with those with non-ECRS. IL-10 neutralization significantly augmented SEB-induced IL-13 and IFN-γ production by NP cells.

Conclusions

Impaired IL-10 production in response to SEB in NP may exacerbate the pathophysiology of ECRS including eosinophilia and lower airway obstruction.  相似文献   
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