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991.
Miyakawa R Ichida T Yamagiwa S Miyaji C Watanabe H Sato Y Yokoyama H Tsukada C Ishimoto Y Sugahara S Yang XH Abo T Asakura H 《Journal of gastroenterology and hepatology》2005,20(7):1126-1130
The human liver contains significant numbers of innate immune cells, such as natural killer (NK) cells and natural killer T (NKT) cells, which express both T-cell receptors and NK-cell receptors simultaneously. It has been suggested that the innate immune system plays a crucial role in the liver. In this report, the distribution of NK and NKT cells in the liver and peripheral blood of two patients with drug-induced fulminant hepatic failure (FHF) who had undergone living donor liver transplantation was examined. In both the liver and peripheral blood, the proportions of NK and NKT cells markedly decreased compared with those in healthy donors. It was also revealed that, unlike murine NKT cells, human CD56(+) T cells and CD57(+) T cells did not constitutively express CD28, which is one of the important costimulatory molecules on T cells. Additionally, the residual CD56(+) T cells and CD57(+) T cells in the patients expressed more CD28 than in controls. This result suggests that NKT cells might be more activated in FHF. Although the accumulation of further cases is required, it is suggested that both NK and NKT cells might be involved in hepatic injury in FHF. 相似文献
992.
Expression and clinical significance of CD44V5 and CD44V6 in resectable colorectal cancer 总被引:16,自引:0,他引:16
Vizoso FJ Fernández JC Corte MD Bongera M Gava R Allende MT García-Muñiz JL García-Morán M 《Journal of cancer research and clinical oncology》2004,130(11):679-686
Purpose This study was conducted to evaluate the prognostic significance of CD44v5 and CD44v6 in resectable colorectal cancer.Materials and methods Membranous CD44v5 and CD44v6 levels were measured by an immunoenzymatic assay in tumors and surrounding mucosal samples obtained from 105 patients with resectable colorectal carcinomas.Results There were no significant differences of CD44v5 levels between tumors [median: 3.2 (range: 0.9–83.5) ng/mg protein) and surrounding mucosal samples (3 (3–146.2) ng/mg protein]. However, tumor samples showed significantly higher CD44v6 levels [19.5 (2.2–562.9) ng/mg protein] than mucosal samples [5 (5–230) ng/mg protein] (P=0.0001). Patients with higher CD44v5 or CD44v6 content in tumor samples had a considerably shorter relapse-free survival (P<0.05, for both). Patients with a higher CD44v6 content also had a shorter relapse-free and overall survival in the multivariate analysis (P<0.05).Conclusion The results of this study suggest a role of CD44v5 and CD44v6 in colorectal cancer progression. Membranous CD44v levels in primary tumors, measured by immunoenzymatic assay, may contribute to a more precise prognostic estimation in patients with resectable colorectal cancer.Supported by grants from ISCIII Red de Centros de Cancer RTICCC (C03/10) and Obra Social Cajastur 相似文献
993.
Lin PC Lee MY Lin JT Hsiao LT Chen PM Chiou TJ 《International journal of hematology》2008,87(4):434-439
CD34+-selected peripheral blood progenitor cells (PBPCs) may not only reduce contaminated tumor cells but also compromise immunologic
reconstitution and increase incidence of infections after transplantation. We analyzed the incidence of virus reactivation
in CD34+-selected PBPCs autologous transplantation. From December 2001 to December 2004, ten high-risk aggressive non-Hodgkin’s lymphoma
(NHL) patients were enrolled in a program of high-dose chemotherapy plus autologous CD34+-selected PBPCs support. Viral screening studies, including clinical symptoms, physical examinations, hepatitis B virus (HBV)-DNA,
cytomegalovirus (CMV)-polymerase chain reaction (PCR), rapid diagnosis of fluorescent antibody stain for herpes-simplex virus
(HSV), and viral culture from blood, fluid or tissue were performed weekly during the first 3 months and then monthly for
1 year. Two of four patients (50%) who were HBV carriers developed HBV reactivation. The other two HBV carriers who received
prophylactic lamivudine therapy did not develop HBV reactivation. Two patients (20%) developed cytomegalovirus (CMV) infection,
and three patients (30%) developed HSV infection in total ten serum-positive patients. The possibility of virus reactivation
might increase in NHL patients undergoing autologous CD34+-selected PBPC transplantation. Administering prophylactic antivirus therapy and closely following patient’s clinical viral
complications should be considered. 相似文献
994.
Ciesek S Liermann H Hadem J Greten T Tillmann HL Cornberg M Aslan N Manns MP Wedemeyer H 《Journal of viral hepatitis》2008,15(3):200-211
Dendritic cells (DCs) play a central role in antiviral immunity. Conflicting data on DC function have been reported for hepatitis C virus (HCV) infection. In addition to antigen presentation and cytokine secretion, a subset of human DCs displays direct cytotoxic activity. It has been suggested that measles virus and human immunodeficiency virus (HIV) may enhance cytotoxicity of DCs potentially leading to apoptosis of activated T cells and subsequent down-regulation of antiviral immune responses. We demonstrate that CD1c-positive myeloid DCs, but not BDCA-4-positive plasmacytoid DCs, are able to kill different target cells mainly via tumour necrosis factor-related apoptosis-inducing ligand. The ability of CD1c+ DCs to lyze target cells was found to be completely impaired in patients with chronic hepatitis C (10 chronic HCV patients vs 10 healthy controls; P < 0.001) but not in patients with primary biliary cirrhosis. Successful antiviral therapy of chronic hepatitis C rescued the cytotoxicity of DCs. Myeloid DCs of HCV patients and healthy controls had a similar phenotype and endocytotic activity, however, the frequency of mDCs in the peripheral blood was lower (P = 0.004) and the allostimulatory function was weaker (P < 0.001) in chronic hepatitis C. Thus, in contrast to HIV and measles virus studies on monocyte-derived DCs, freshly isolated myeloid DCs of patients with hepatitis C do not show an increased but a completely abolished cytotoxic activity. The impaired DC cytotoxicity could represent a novel mechanism for the increased prevalence of autoimmunity in HCV infection. 相似文献
995.
Paczkowska E Larysz B Rzeuski R Karbicka A Jałowiński R Kornacewicz-Jach Z Ratajczak MZ Machaliński B 《European journal of haematology》2005,75(6):461-467
The hematopoietic and non-hematopoietic stem/progenitor cells harvested directly from the bone marrow (BM) or G-CSF mobilized peripheral blood were demonstrated to play an important role in regeneration of damaged organs (1, 2). Here, we asked if the stroke- or acute heart infarct-related stress triggers mobilization of stem/progenitor-enriched CD34(+)cells from the BM into the peripheral blood, which subsequently could contribute to regeneration of damaged tissues. To address this question the peripheral blood samples were harvested from patients with ischemic stroke during the first 24 h of manifestation of symptoms and on the second and sixth day afterwards or during the first 24 h of acute cardiac pain as well as on the second and sixth day of infarct. We measured in these patients (i) percentage of circulating hematopoietic stem/progenitor-enriched CD34(+) cells in peripheral blood by employing fluorescence activated cell sorter (FACS) and (ii) number of hematopoietic progenitor cells for the granulocyte-monocytic colony-forming unit (CFU-GM) and erythoid burst-forming unit (BFU-E) lineages circulating in peripheral blood. We concluded that stress related to ischemic stroke or acute myocardial infarction triggers the mobilization of hematopoietic stem/progenitor-enriched CD34(+) cells from the BM into peripheral blood. These circulating stem/progenitor-enriched CD34(+) cells may contribute to the regeneration of ischemic tissues, however, this possibility requires further studies. 相似文献
996.
Cao TV La M Getting SJ Day AJ Perretti M 《Microcirculation (New York, N.Y. : 1994)》2004,11(7):615-624
OBJECTIVE: The authors investigated whether the anti-inflammatory protein tumor necrosis factor (TNF)-stimulated gene-6 (TSG-6) and its Link module (Link_TSG6) could affect the complex multistep process of leukocyte/endothelial cell (EC) interaction. METHODS: Mouse mesenteries were inflamed with interleukin (IL)-1beta and the extent of leukocyte rolling, adhesion, and emigration was determined after 2 h. Link_TSG6 and a single-point mutant (termed K13E) were given intraperitoneally together with the cytokine. Human neutrophil chemotaxis and transmigration were determined in vitro in response to IL-8 and/or TNF-alpha. TSG-6, Link_TSG6, and K13E were added to the leukocytes or the EC monolayers. RESULTS: Co-injection of Link_TSG6 with IL-1beta selectively inhibited cell flux, adhesion, and emigration as analyzed in mesenteric postcapillary venules. The fewer cells that rolled in the animals treated with Link_TSG6 displayed a velocity similar to that measured in vehicle-treated mice. In vitro, Link_TSG6 did not affect neutrophil chemotaxis or EC activation but did inhibit neutrophil transmigration across EC monolayers. The latter effect was shared by full-length TSG-6 and observed equally in response to IL-8 or TNF-alpha. CONCLUSIONS: These data restrict the site of action for at least some of the anti-inflammatory effects ascribed to TSG-6/Link_TSG6 to the microenvironment of the extravasating leukocyte. 相似文献
997.
Bolognesi A Polito L Tazzari PL Lemoli RM Lubelli C Fogli M Boon L de Boer M Stirpe F 《British journal of haematology》2000,110(2):351-361
Immunotoxins specific for the CD80 and CD86 antigens were prepared by linking three type 1 ribosome-inactivating proteins (RIPs), namely bouganin, gelonin and saporin-S6, to the monoclonal antibodies M24 (anti-CD80) and 1G10 (anti-CD86). These immunotoxins showed a specific cytotoxicity for the CD80/CD86-expressing cell lines Raji and L428. The immunotoxins inhibited protein synthesis by target cells with IC50s (concentration causing 50% inhibition) ranging from 0.25 to 192 pmol/l as RIPs. The anti-CD80 immunotoxins appeared 1-2 log more toxic for target cells than the anti-CD86 ones. Immunotoxins containing saporin and bouganin induced apoptosis of target cells. The toxicity for bone marrow haemopoietic progenitors of these conjugates was also evaluated. Bouganin and related immunotoxins at concentrations up to 100 nmol/l did not significantly affect the recovery of committed progenitors or of more primitive cells. The saporin-containing immunotoxins at concentrations >/= 1 nmol/l showed some toxicity on colony-forming unit cells (CFU-C). The expression of the CD80 and CD86 molecules is prevalently restricted to antigen-presenting cells and is also strong on Hodgkin and Reed-Sternberg cells in Hodgkin's disease. Present results suggest that immunotoxins targeting type 1 ribosome-inactivating proteins to these antigens could be considered and further studied for the therapy of Hodgkin's disease or other CD80/CD86-expressing tumours. 相似文献
998.
G Muiesan C L Alicandri E Agabiti-Rosei R Fariello M Beschi E Boni M Castellano E Moniti L Muiesan G Romanelli A Zanielli 《The American journal of cardiology》1982,49(6):1420-1424
Captopril was given to 15 unselected patients with essential hypertension (WHO II) at a dose range of 300 to 600 mg/day. Hemodynamic indexes (thermodilution) as well as levels of plasma norepinephrine, epinephrine, renin activity and aldosterone were determined simultaneously at the end of 2 weeks of placebo and after 8 weeks of captopril treatment. Systolic and diastolic arterial pressures were reduced significantly by treatment both supine (p less than 0.0025) and standing (p less than 0.0025). The diastolic arterial pressure was normalized (less than 95 mm Hg) in five patients and significantly reduced in four, whereas six patients were considered poor responders (mean arterial pressure decrease 10 mm Hg or less). The decrease in arterial pressure correlated significantly with the reduction in total peripheral resistance (r = 0.71), whereas cardiac index did not change and stroke index increased because of a slight decrease of heart rate. Plasma and urinary norepinephrine and epinephrine did not change during treatment. Moreover, the response of both heart rate and plasma catecholamines to upright posture was not altered by captopril treatment. Plasma renin activity increased and plasma aldosterone concentration decreased during treatment. These results suggest that inhibition of converting enzyme activity by captopril induces a reduction in arterial pressure through a reduction in total peripheral resistance. There was no evidence of an appreciable reduction in sympathetic nervous system activity during therapy. 相似文献
999.
Barnett D Granger V Kraan J Whitby L Reilly JT Papa S Gratama JW 《British journal of haematology》2000,108(4):784-792
The European Working Group on Clinical Cell Analysis (EWGCCA) has, in preparation for a multicentre peripheral blood stem cell clinical trial, developed a single-platform flow cytometric protocol for the enumeration of CD34+ stem cells. Using this protocol, stabilized blood and targeted training, the EWGCCA have attempted to standardize CD34+ stem cell enumeration across 24 clinical sites. Results were directly compared with participants in the UK National External Quality Assessment Scheme (NEQAS) for CD34+ Stem Cell Quantification that analysed the same specimens using non-standardized methods. Two bead-counting systems, Flow-Count and TruCount, were also evaluated by the EWGCCA participants during trials 2 and 3. Using Flow-Count, the intralaboratory coefficient of variation (CV) was = 5% in 39% of the laboratories (trial 1), increasing to 65% by trial 3. Interlaboratory variation was reduced from 23.3% (trial 1) to 10.8% in trial 3. In trial 2, 70% of laboratories achieved an intralaboratory CV = 5% using TruCount, increasing to 74% for trial 3; the interlaboratory CV was reduced from 23.4% to 9.5%. Comparative analysis of the EWGCCA and the UK NEQAS cohorts revealed that EWGCCA laboratories, using the standardized approach, had lower interlaboratory variation. Thus, the use of a common standardized protocol and targeted training significantly reduced intra- and interlaboratory CD34+ cell count variation. 相似文献
1000.
Expression of human chorionic gonadotropin, CD44v6 and CD44v4/5 in esophageal squamous cell carcinoma 总被引:5,自引:0,他引:5
Li DM Li SS Zhang YH Zhang HJ Gao DL Wang YX 《World journal of gastroenterology : WJG》2005,11(47):7401-7404
AIM: To study the relationship between the expression of human chorionic gonadotropin (HCG), CD44v6, CD44v4/5 and the infiltration, metastasis of esophageal squamous cell carcinoma. METHODS: By labeled streptavidin-biotin technique, the expressions of HCG, CD44v6, and CD44v4/5 in 42 patients with esophageal squamous cell carcinoma were examined. RESULTS: The positive rate of HCG expression in patients with lymph node metastasis was 85.71% (18/21), higher than that (57.14%, 12/21) in those without lymph node metastasis (P<0.05). The positive rate of CD44v6 expression was 71.43% (15/21) in lymph node metastasis group, and 38.09% (8/21) in non-metastasis group; there was a significant difference between the two groups (P<0.05). The positive rate of CD44v4/5 expression was 76.19% (16/21) in lymph node metastasis group, and 42.86% (9/21) in non-metastasis group; there was also a significant difference between them (P<0.05). From grade Ⅰ to grade Ⅲ in differentiation, the positive rate of HCG expression was 84.62% (11/13), 70.59% (12/17) and 58.33% (7/12), respectively; there was no significant difference among them (P<0.05). The positive rate of CD44v6 expression in grades Ⅰ-Ⅲ of cancer tissues was 76.92% (10/13), 52.94% (9/17), and 33.33% (4/12) respectively; there was no significant difference among them. The positive rate of CD44v4/5 expression in grades Ⅰ-Ⅲ of cancer tissues was 69.23% (9/13), 64.71% (11/17), and 41.67% (5/12) respectively; there was no significant difference among the three groups. There was no correlation between the positive rates of HCG and CD44v6, CD44v4/5 expression. Cancer cells in carcinomatous emboli and those infiltrating into vascular wall strongly expressed HCG, CD44v6, and CD44v4/5. CONCLUSION: Expression of HCG, CD44v6, and CD44v4/5 in esophageal squamous cell carcinoma is related to its infiltration and metastasis. HCG, CD44v6, and CD44v4/5 have different effects on the infiltration and metastasis of esophageal squamous cell carcinoma. 相似文献