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891.
892.
893.
The objective of the present study was to determine the effects of porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) vaccinations in an experimental PCV2-PRRSV challenge model, based on virological (viremia), immunological (neutralizing antibodies [NAs], gamma interferon-secreting cells [IFN-γ-SCs], and CD4+ CD8+ double-positive cells), and pathological (lesions and antigens in lymph nodes and lungs) evaluations. A total of 72 pigs were randomly divided into 9 groups (8 pigs per group): 5 vaccinated and challenged groups, 3 nonvaccinated and challenged groups, and a negative-control group. Vaccination against PCV2 induced immunological responses (NAs and PCV2-specific IFN-γ-SCs) and reduced PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. However, vaccination against PCV2 did not affect the PRRSV immunological responses (NAs and PRRSV-specific IFN-γ-SCs), PRRSV viremia, PRRSV-induced lesions, or PRRSV antigens in the dually infected pigs. Vaccination against PRRSV did not induce immunological responses (PRRSV-specific IFN-γ-SCs) or reduce PRRSV viremia, PRRSV-induced lesions, or PRRSV antigens in the dually infected pigs. In addition, vaccination against PRRSV increased PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. In summary, vaccination against PCV2 reduced PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. However, vaccination against PRRSV increased PCV2 viremia, PCV2-induced lesions, and PCV2 antigens in the dually infected pigs. Therefore, the PCV2 vaccine decreased the potentiation of PCV2-induced lesions by PRRSV in dually infected pigs. In contrast, the PRRSV vaccine alone did not decrease the potentiation of PCV2-induced lesions by PRRSV in dually infected pigs.  相似文献   
894.
Intravascular papillary endothelial hyperplasia (IPEH) is histopathologically characterized by endothelium-lined papillary structures encircling an acellular fibrin core. The process of IPEH pathogenesis is unclear. The purpose of our study was to identify histopathological and immunohistochemical characteristics of IPEH to better understand the pathogenesis of this disease. After reviewing microscopic and medical records from Kyungpook National University Hospital, we selected 16 cases of IPEH. Masson’s trichrome and immunohistochemical staining as well as hematoxylin-eosin staining for 16 cases of IPH were performed. Immunohistochemical studies included CD31, CD68, mast cell tryptase, hypoxia-inducible factor-1 (HIF-1α), and vascular endothelial growth factor (VEGF). Sections from all our cases showed three distinct histological regions including a papillary portion with hyalinized fibrous or fibroblastic cores, an area containing an unorganized thrombus, and organization area with an ingrowth of endothelial cells, myofibroblasts, and fibroblasts. In the organization area, HIF-1α-positive cells were identified in the loose connective tissue. Endothelial cells forming vascular channels were negative for HIF-1α while VEGF was highly expressed in both interstitial mononuclear and endothelial cells. In the papillary portion, the cellular cores were strongly positive for both HIF-1α and VEGF, but the acellular cores were negative. Our investigation confirmed that IPEH is a reactive lesion that incidentally arises during the organization process of older thrombi. It was also found that HIF-1α and VEGF expression was dependent on the thrombus remodeling stage in cases of IPEH.  相似文献   
895.
It is generally accepted that the three semicircular canals are set at right angles to each other and the lateral semicircular canal is smaller than the anterior and posterior semicircular canals. Precise knowledge of the size and spatial relationships of the semicircular canals is vital, and so the 40 petrous parts of the temporal bones were scanned by micro‐CT at a slice thickness of 35 µm. The micro‐CT images were used in reconstructing three‐dimensional models of the bony labyrinth using computer software. Various dimensions of the semicircular canals were measured using the software, and statistical analysis was performed. The anterior semicircular canal was slightly wider than the posterior semicircular canal, and their heights were similar. The radius of curvature of the lateral semicircular canal was 20% smaller than those of the anterior and posterior semicircular canals. The angles between the three canals were not exactly 90 degrees: they were 92.1, 84.4, and 86.2 degrees between the anterior and posterior, anterior and lateral, and posterior and lateral semicircular canals, respectively. We obtained high‐resolution images of the semicircular canals using three‐dimensional reconstruction software, and these were used to precisely measure the angles between the semicircular canals and the area of the distorted circle formed by each semicircular canal. Anat Rec, 296:834–839, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
896.

Purpose

The lipid entities of cell membranes are components of the immune system and important mediators of inflammation. Despite increasing interest in the function of epithelial cells in inflammation, the role of cholesterol in this process has not been described. Here, we investigated the effect of cholesterol depletion on the inflammatory process in airway epithelial cells via the expression of interleukin (IL)-8 as a marker of inflammation.

Methods

A 549 cells were treated with 0.5% methyl-β-cyclodextrin as a selective cholesterol extractor. The IL-8 level was assessed by enzyme-linked immunosorbent assay and reassessed after cholesterol repletion. Mitogen-activated protein kinase (MAPK) inhibitors were used to determine the upstream signaling pathway for IL-8 production in cholesterol-depleted cells.

Results

We found a relationship between the amount of cholesterol in A 549 cells and inflammation of the airway. IL-8 production was increased in cholesterol-depleted A 549 cells and restored by cholesterol repletion. IL-8 production was decreased by pretreatment with the extracellular signal-regulated kinase (ERK) inhibitor U0126 but not with JNK inhibitor II or the p38 MAPK inhibitor SB202190.

Conclusions

Our findings suggest that inflammatory responses are increased in cholesterol-depleted epithelial cells via the MAPK signaling system, predominantly by the ERK pathway. We conclude that the lipid components of airwayepithelial cells may play a role in the inflammatory process.  相似文献   
897.

Purpose

Prostaglandin (PG) E2 is an immunomodulatory lipid mediator generated mainly via the cyclooxygenase-2 (COX-2) pathway from arachidonic acid at sites of infection and inflammation. A positive feedback loop of PGE2 on COX-2 expression is critical for homeostasis during toll-like receptor (TLR)-mediated inflammatory processes. The mechanism of PGE2-regulated COX-2 expression remains poorly understood. The low-molecular-weight stress protein heme oxygenase-1 (HO-1) contributes to the anti-inflammatory, anti-oxidant and anti-apoptotic response against environmental stress.

Methods

We explored the involvement of HO-1 on PGE2 regulation of LPS-induced COX-2 expression in RAW 264.7 macrophages.

Results

LPS-induced COX-2 expression in RAW 264.7 macrophages was enhanced by exogenous PGE2 or cyclic AMP (cAMP) analogue and was suppressed by a COX inhibitor (indomethacin), a protein kinase A (PKA) inhibitor (KT5720), and A kinase anchoring protein (AKAP) disruptors (Ht31 and RIAD). This result suggests that the stimulatory effects of endogenous and exogenous PGE2 on COX-2 expression are mediated by a cAMP-PKA-AKAP-dependent pathway. The induction of HO-1 was observed in LPS-stimulated RAW 264.7 macrophages. This induction was suppressed by exogenous PGE2 and enhanced by blockage of the endogenous PGE2 effect by the PKA inhibitor or AKAP disruptors. In addition, HO-1 induction by the HO activator copper protoporphyrin suppressed LPS-induced COX-2 expression, which was restored by the addition of exogenous PGE2. The induction of HO-1 inhibited LPS-induced NF-κB p-65 nuclear expression and translocation.

Conclusions

AKAP plays an important role in PGE2 regulation of COX-2 expression, and the suppression of HO-1 by PGE2-cAMP-PKA-AKAP signaling helps potentiate the LPS-induced COX-2 expression through a positive feedback loop in RAW 264.7 macrophages.  相似文献   
898.
Prognosis is an essential part of the baseline assessment of any disease. For predicting prognosis of end-stage liver disease, many prognostic models were proposed. Child-Pugh score has been the reference for assessing the prognosis of cirrhosis for about three decades in end-stage liver disease. Despite of several limitations, recent large systematic review showed that Child-Pugh score was still robust predictors and it''s components (bilirubin, albumin and prothrombin time) were followed by Child-Pugh score. Recently, Model for end-stage liver disease (MELD) score emerged as a "modern" alternative to Child-Pugh score. The MELD score has been an important role to accurately predict the severity of liver disease and effectively assess the risk of mortality. Due to several weakness of MELD score, new modified MELD scores (MELD-Na, Delta MELD) have been developed and validated. This review summarizes the current knowledge about the prognostic factors in end-stage liver disease, focusing on the role of Child-Pugh and MELD score.  相似文献   
899.
Autoimmune hepatitis (AIH) has been reported in association with Sjögren''s syndrome (SS). Drug-induced AIH has been rarely reported. A rare case of the co-development of AIH and SS in a 53-year-old woman after the consumption of herbal medicines is described. After admission, the patient complained of dryness in her mouth, and she was subsequently diagnosed with SS, which had not been detected previously. The patient''s bilirubin and aminotransferase levels initially decreased following conservative management; however, they later began to progressively increase. A diagnosis of AIH was made based on the scoring system proposed by the International Autoimmune Hepatitis Group. The patient was administered a combination of prednisolone and azathioprine, and the results of follow-up liver-function tests were found to be within the normal range. This is an unusual case of AIH and SS triggered simultaneously by the administration of herbal medicines.  相似文献   
900.
Hepatoid adenocarcinoma (HAC) is a rare type of extrahepatic carcinoma whose morphology is similar to that of hepatocellular carcinoma (HCC). Metachronous HCC and HAC in the same patient is extremely rare. The case of a 68-year-old man with chronic hepatitis B infection who had both HCC and HAC of the stomach is reported herein. Nine years previously this patient had been diagnosed with HCC and received a right lobectomy. HCC that recurred at the caudate lobe at 6 months after the operation was successfully treated with transarterial chemoembolization. The patient was followed up regularly thereafter without evidence of tumor recurrence for 9 years. In July 2010 his serum alpha-fetoprotein (AFP) level elevated from 6.5 ng/mL to 625.4 ng/mL, and he developed a probable single metastatic lymph node around the hepatic artery without intrahepatic lesions. Subsequent evaluation with upper endoscopy revealed a 4-cm ulcerative lesion on the antrum of the stomach. Subtotal gastrectomy was performed with lymph-node dissection. Histologic examination revealed a special type of extrahepatic AFP-producing adenocarcinoma-HAC with lymph-node metastasis-which indicates that HAC can be a cause of elevated AFP even in patients with HCC. HAC should be considered if a patient with stable HCC exhibits unusual elevation of AFP.  相似文献   
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