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PURPOSE: Neovascularization is known to be one of the major characteristics of human hepatocellular carcinoma (HCC). Angiogenin (ANG), originally discovered in a human colon cancer cell line, is a liver-derived polypeptide that shows strong angiogenic activity in vivo. However, the role of ANG on the development of HCC remains unknown. The present study was designed to examine the implication of ANG in the neovascularization of human HCC. EXPERIMENTAL DESIGN: Forty-one HCC patients who had undergone conventional celiac angiography were used in this study. ANG protein expression and microvessel density (MVD) in HCC specimens obtained by liver biopsy or surgical resection were examined by immunohistochemistry, and the levels were quantified by the KS-400 image analyzing system. ANG mRNA expression in liver tissues was evaluated by in situ hybridization. Serum ANG concentrations were measured by an ELISA. Survival rates were calculated using the Kaplan-Meier method. RESULTS: Immunohistochemistry and in situ hybridization showed greater increments of ANG protein expression and mRNA expression, respectively, in HCC tissues than in the surrounding nontumorous tissues. MVD within tumorous tissues increased according to dedifferentiation of the histological grade of HCC, showing a significant correlation (r = 0.877, P = 0.0009) with ANG expression levels. Mean +/- SD serum ANG levels of healthy subjects and chronic hepatitis (CH) patients were 362.3 +/- 84.1 ng/ml and 331.9 +/- 133.8 ng/ml, respectively, with no significant difference. Serum ANG levels of liver cirrhosis patients (242.4 +/- 126.9 ng/ml) were lower than those of healthy subjects or CH patients and decreased as the fibrosis grade advanced. In HCC patients, despite the cirrhotic background, serum ANG levels increased as the tumor vascularity increased (197.8 +/- 64.9 ng/ml for hypovascular, 326.7 +/- 148.6 ng/ml for hypervascular, and 405.0 +/- 121.3 ng/ml for very hypervascular), in good accordance with histological grading, and significantly decreased (P = 0.015) after successful treatment with transcatheter arterial embolization or percutaneous ethanol injection. HCC patients were conventionally divided into two groups according to the serum level of ANG, those with values higher than the mean level (332.9 +/- 143.8 ng/ml) and those with values lower than the mean,; the 5-year survival rate of the latter group was determined to be significantly higher than that in the former group. CONCLUSIONS: These results suggest that ANG is one of the neovascularization defining factors of HCC. Thus, measuring serum ANG may assist in monitoring the disease, and targeting ANG may provide a new strategy for treating advanced HCC.  相似文献   
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Blood levels of inflammatory-related cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, are elevated in patients with alcoholic liver diseases. We investigated the effects of these cytokines and ethanol on the expression of hepatic asialoglycoprotein receptors (AGPRs) in a human hepatoblastoma cell line, HepG2. An [125I]-asialo-orosomucoid binding assay showed significant increases in surface AGPR numbers in HepG2 cells by treatment with IL-1β, IL-6, and TNF-α, to levels which were approximately 130% of the values in untreated control cells. However, the enhanced AGPR numbers induced by treatment with these cytokines were markedly suppressed, to 70%–80% of the number in the untreated cells, by treatment with ethanol. Immunological detection of AGPR with a specific antibody demonstrated that the modulation of surface AGPR numbers was correlated with the cellular expression levels of AGPR. These results suggest that, although IL-1β, IL-6, and TNF-α stimulate the synthesis of hepatic AGPR, ethanol suppresses the expression of AGPR augmented by these cytokines. This leads to an increase in serum asialo-orosomucoid levels caused by the disordered catabolism mediated by AGPR in patients with alcoholic liver disease. (Received Dec. 5, 1997; accepted May 22, 1998)  相似文献   
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OBJECTIVE: Transplantation of hematopoietic stem cells (HSCs) is usually accomplished through intravenous injection, a complex process that requires recognition of bone marrow vasculature and migration to a supportive microenvironment. Hence, some populations of HSCs, including cord blood (CB) Lin(-)CD34(-) stem cells, do not engraft well in bone marrow (BM) of nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. In this study, we examined the effect of human stromal interactions on the properties of CB Lin(-)CD34(-) cells. MATERIALS AND METHODS: CD34 and CXCR4 expression on fresh CB Lin(-)CD34(-) cells and CB Lin(-)CD34(-) cells cocultured with human stromal cells were analyzed. Homing activity and engraftment of these cells were assessed using NOD/SCID mice. In an attempt to identify the stromal CXCR4-inducing factor, CB Lin(-)CD34(-) cells were cocultured with a noncontact culture system in the presence of several inhibitors. RESULT: Coculture with human stromal cells induced expression of CD34 and CXCR4 on CB Lin(-)CD34(-) cells. CXCR4 expression on CB Lin(-)CD34(-) cells was induced even in the noncontact culture condition, suggesting that this CXCR4-inducing factor is soluble. Moreover, CXCR4 induction was inhibited by the soluble Wnt inhibitor DKK1. Furthermore, these cells acquired homing activity and engrafted in the BM of NOD/SCID mice after intravenous injection. CONCLUSION: These findings may be useful for understanding the role of stromal cells in homing and engraftment of HSCs.  相似文献   
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INTRODUCTIONMalignant fibrous histiocytoma is one of the most common soft tissue sarcomas in late adult life. But primary visceral malignant fibrous histiocytoma is a very rare entity. In peripheries, it is known to have an aggressive behavior but its biological pattern when involving liver and spleen is not well understood due to the rarity of its occurrence.PRESENTATION OF CASEA case of malignant fibrous histiocytoma of the liver and spleen as multiple cystic lesions in a 30 years old man is reported. The patient presented with hepatosplenomegaly resulting in central abdominal distention. Pre-operative investigations pointed toward the diagnosis of malignant cystic disease. The tumor presented as multiple hepatic cysts with massive hepatomegaly and splenomegaly. These cysts contained hemorrhagic fluid. Biopsy revealed highly cellular pleomorphic spindle cells fascicles arranged in storiform pattern at places with frequent mitoses. Immunohistochemistry revealed viamentin positivity. The tumor is compared with previous case reports.DISCUSSIONMalignant fibrous histiocytoma of liver and spleen has been mentioned in the literature as isolated case reports and most of these present as solid lesions but presentation as multiple cysts is also a possibility as was seen in this patient. It can be confirmed only on histo-pathology supported by immunohistochemistry. The disease carries guarded prognosis due to its rapid progression and diagnostic dilemma pre-operatively.CONCLUSIONThis rare malignancy affecting the viscera can be diagnosed only with high index of suspicion and awareness regarding its presentation can help surgeons deal with it.  相似文献   
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Early region 1 of the adenovirus type 5 genome was replaced with a DNA sequence containing the gene coding for the hepatitis B surface antigen (HBsAg) flanked by the major late promoter from adenovirus 2 and processing and polyadenylylation signals from simian virus 40. In one type of hybrid virus only the adenovirus 2 major late promoter, including just 33 base pairs of the adenovirus type 2 tripartite leader, preceded the coding region of the HBsAg gene. In another, this region was preceded by both the adenovirus major late promoter and almost the entire tripartite leader. The structure of the substituted sequence in each of the recombinant viral DNAs was identical to that in the plasmids used to construct the viruses. Approximately equivalent amounts of HBsAg-specific mRNA were produced late in infection with each recombinant virus. Although HBsAg production was detected late in infection of the hybrid virus not containing the full tripartite leader sequence, its level was 1/70th of that obtained with the hybrid virus containing this sequence. One likely interpretation is that the presence of the tripartite leader at the 5' end of this mRNA is critical for the synthesis of HBsAg polypeptide in the late stage of infection. HBsAg produced upon infection with the hybrid adenoviruses was glycosylated and secreted into the culture medium as particles that were essentially indistinguishable from the 22-nm particles found in human serum.  相似文献   
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Narrowband ultraviolet B phototherapy (NB-UVB) is a therapeutic alternative for haematopoietic stem cell transplantation-related skin graft-versus-host disease (GVHD). The beneficial effects of this intervention may be induced by direct irradiation of inflammatory cells in the skin; however, the putative involvement of indirect effects on systemic immunity has not been elucidated. To address this issue, 11 acute skin GVHD patients refractory to standard corticosteroid treatment and with no gut/liver involvement were treated with NB-UVB irradiation. The median number of treatments was 10 times, with a mean cumulative exposure of 6.36 J/cm2. No other immunosuppressive therapy was initiated during irradiation. Eight patients achieved an objective complete response, two had a partial response, and one showed no change. None of the patients experienced progressive skin GVHD or newly diagnosed gut/liver GVHD. NB-UVB was well tolerated, with no patients discontinuing irradiation due to toxicity. We additionally demonstrated by flow cytometry that NB-UVB irradiation induces the increment of the proportion of regulatory T cell (Tregs) in patients’ peripheral blood. These results suggest that NB-UVB may exert beneficial effects on steroid-refractory skin GVHD through the expansion of Tregs.  相似文献   
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