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311.
Complete long term follow up was obtained in 27 children who had bled from oesophageal varices. Most presented with haematemesis or melaena at an average age of 5.2 years in the portal vein thrombosis group (20 children) and 9.5 years in the intrahepatic group (7 children). All had splenomegaly. Only 6 of 20 children with portal vein thrombosis had a possible precipitating factor. A total of 182 admissions for bleeding are reported, in 68 of which injection sclerotherapy was used to control bleeding. Control rate with injection sclerotherapy was 97%. Shunts performed below age 10 years were associated with a high thrombosis rate. A conservative approach to bleeding varices in children is recommended with transfusion, pitressin, and injection sclerotherapy. Oesophageal transection may have a role in the emergency management of the few children in whom bleeding is not controlled by injection sclerotherapy.  相似文献   
312.
Dr. B. Auner  I. Marzi 《Der Chirurg》2014,85(5):451-464
Multiple trauma in children is rare so that even large trauma centers will only treat a small number of cases. Nevertheless, accidents are the most common cause of death in childhood whereby the causes are mostly traffic accidents and falls. Head trauma is the most common form of injury and the degree of severity is mostly decisive for the prognosis. Knowledge on possible causes of injury and injury patterns as well as consideration of anatomical and physiological characteristics are of great importance for treatment. The differences compared to adults are greater the younger the child is. Decompression and stopping bleeding are the main priorities before surgical fracture stabilization. The treatment of a severely injured child should be carried out by an interdisciplinary team in an approved trauma center with expertise in pediatrics. An inadequate primary assessment involves a high risk of early mortality. On the other hand children have a better prognosis than adults with comparable injuries.  相似文献   
313.
细胞黏附力和黏附分子对癌侵袭性影响的研究展望   总被引:3,自引:1,他引:3  
  相似文献   
314.
In a patient with acute myeloid leukaemia, treated with several courses of chemotherapy including a fludarabine-containing regimen, severe symptoms due to Epstein-Barr virus reactivation occurred but could be successfully treated with the monoclonal anti-CD20 antibody rituximab. Depletion of viral host cells may be effective in treatment of symptoms due to Epstein-Barr virus reactivation.  相似文献   
315.
Zhou  MX; Findley  HW Jr; Ragab  AH 《Blood》1989,74(4):1355-1359
We are reporting here that low-mol wt B-cell growth factor (LMW-BCGF) and recombinant interleukin-2 (rIL-2) are together able to induce CD3+ cytotoxic T lymphocytes (CTL) with lymphokine-activated killer cell (LAK) activity from the bone marrow (BM) cells of children with acute lymphoblastic leukemia (ALL). Ficoll-Hypaque (FH)-separated BM cells were obtained from patients with active disease (at diagnosis N = 13, in relapse N = 15) and in complete remission (CR; N = 12). CD3+ cells were removed by Leu-4 antibody and immunobeads. Cells were cultured (10(5) cells/mL) in semisolid media with rIL-2 (100 mu/mL), LMW-BCGF (0.1 mu/mL), and the combination of rIL-2 plus LMW-BCGF, respectively, for seven to ten days. Pooled colonies were harvested for phenotyping. LMW-BCGF plus rIL-2 induced large numbers of CD3+ colonies from CD3- precursors. rIL-2 alone did not induce colony formation. In addition, cells were cultured in liquid media with LMW-BCGF, rIL-2, and the combination of LMW-BCGF plus rIL-2, respectively, for seven to 21 days. They were harvested for phenotyping, and cytotoxicity assays were performed v K562, Raji, and autologous leukemic cells. LMW-BCGF plus rIL-2 induced significant expansion of CD3+ cells from CD3- precursors, and these cells were activated to kill autologous leukemic cells in addition to Raji and K562 cell lines. LMW-BCGF or rIL-2 alone did not induce significant expansion or activation of cytotoxic CD3- cells. Our hypothesis is that LMW-BCGF plus rIL-2 stimulates the proliferation and activation of CD3- precursors from the BM cells of children with acute leukemia to become CD3+ cells that have LAK activity. This finding may have therapeutic implications.  相似文献   
316.
患者女性,50岁,黑龙江省七台河市新兴煤矿面包厂工人。2006年11月25日早饭后自觉腹胀,持续1d,因无食欲未再进食。次日清晨,患者呕吐活虫20余条,从中捡出7条置于小瓶中,来哈尔滨医科大学附属第二医院就诊。经胃肠钡餐造影,未见异物。经本教研室鉴定,7条虫体为蛞蝓(Li  相似文献   
317.
WNT5A has recently been implicated in inflammatory processes, but its role as a bone marrow stromal cell (BMSC)-derived mediator of joint inflammation in arthritis is unclear. Here, we investigated whether inflammatory stimuli induce WNT5A in BMSC to control inflammatory responses. WNT5A levels were determined in human BMSC after stimulation with lipopolysaccharide (LPS) or tumor necrosis factor α (TNF-α,) and in synovial cells and tissue of patients with rheumatoid arthritis (RA) and human TNF-α transgenic (hTNFtg) mice. A microarray analysis of WNT5A-treated murine osteoblasts was performed using Affymetrix gene chips. The regulation of cytokine/chemokine expression was confirmed by qPCR, ELISA, and Luminex technology in BMSC after stimulation with WNT5A or WNT5A knockdown. Relevant signaling pathways were identified using specific inhibitors. Migration of MACS-purified T lymphocytes and monocytes was assessed using the FluoroBlok system. WNT5A expression was increased threefold in BMSC after stimulation with LPS or TNF-α. Synovial fibroblasts from patients with RA showed a twofold increase of WNT5A expression compared with control cells, and its expression was highly induced in the synovial tissue of patients with RA and hTNFtg mice. Microarray analysis of WNT5A-treated osteoblasts identified cytokines and chemokines as targets. The induction of IL-1β, IL-6, CCL2, CCL5, CXCL1, and CXCL5 by WNT5A was confirmed in BMSC and depended on the activation of the NF-κB, mitogen-activated protein (MAPK), and Akt pathways. Accordingly, knockdown of WNT5A markedly reduced the basal and LPS-induced cytokine/chemokine production. Finally, migration of monocytes and T cells toward the supernatant of WNT5A-treated BMSC was increased by 25% and 20%, respectively. This study underlines the critical role of BMSC-derived WNT5A in the regulation of inflammatory processes and suggests its participation in the pathogenesis of RA.  相似文献   
318.
319.
To establish the value of the second-generation recombinant immunoblot assay (RIBA-2) and cDNA polymerase chain reaction (cDNA PCR) for confirmation of hepatitis C virus (HCV) infection, anti-HCV reaction patterns and the presence of HCV RNA were examined in 610 blood donors and 255 non-A, non-B hepatitis patients who were positive or indeterminate in RIBA-2. Of RIBA-2-positive donors (n = 191) and patients (n = 224), 75.4 and 89.7 percent, respectively, were HCV RNA positive. The most frequently observed anti-HCV recognition patterns in HCV RNA-positive donors and patients were c22, c33c, and c100 and/or 5- 1-1 (67.3%, 57.7%) and c22, c33c (24.8%, 29.3%). Among subjects with a RIBA-2-indeterminate result, HCV RNA was detected more often in patients (n = 31) than in donors (n = 419): 67.7 and 2.1 percent, respectively. In viremic persons with single-band reactivity in RIBA-2, this reactivity was always directed against either c22 or c33c. HCV RNA was detected by cDNA PCR in none of 162 persons with only anti-c100 and/or anti-5-1-1 reactivity. Therefore, RIBA-2 reactivity against c100 in combination with 5-1-1 should not be considered positive but indeterminate. In RIBA-2-indeterminate persons, HCV RNA detection is necessary for reliable confirmation of HCV infection.  相似文献   
320.
BACKGROUND: In a confirmatory laboratory, the second-generation recombinant immunoblot assay (RIBA-2) was replaced by the third- generation RIBA (RIBA-3) in March 1993. The aim of this validation study was to compare the sensitivity and specificity of RIBA-2 and RIBA- 3 in a routine setting, by using a validated hepatitis C virus (HCV) RNA polymerase chain reaction to establish plasma viremia. STUDY DESIGN AND METHODS: RIBA-2 testing was performed (March 1991-March 1993) in 593 HCV RNA-positive and 1498 HCV RNA-negative subjects. RIBA-3 testing was performed (March 1993-May 1994) in 220 HCV RNA-positive and 530 HCV RNA-negative subjects. All samples reacted for anti-HCV in enzyme- linked immunosorbent assay. RESULTS: In HCV RNA-positive individuals, the sensitivity of RIBA-3 was significantly higher than that of RIBA-2 (99.5% vs. 93.3%, p = 0.0005). This was not caused by inclusion of the NS5 antigen, but by a higher sensitivity of the antigens c33 and c100 (RIBA-2: 94.3% and 62.6%; RIBA-3: 99.5% and 88.6%). Replacement of the c22 and c100 recombinant proteins by synthetic peptides significantly reduced nonspecific reactivity against these antigens (p < 0.0001). Unfortunately, increased nonspecific reactivity against the modified c33 antigen and the new NS5 antigen canceled out this effect. Two-band reactivity occurred more often in nonviremic persons than in viremic persons (32.7% vs. 8.2%, p < 0.0001). Risk factors for HCV infection were less frequently observed in 11 blood donors with two-band reactivity than in 6 blood donors with other positive RIBA-3 patterns (18% vs. 83%, p = 0.03). CONCLUSION: The higher sensitivity of RIBA-3 significantly reduced the number of indeterminate test results in HCV RNA-positive persons. Confirmatory laboratories must be aware of the frequent occurrence of nonspecific, isolated reactivity and even nonspecific, two-band reactivity in anti-HCV enzyme-linked immunosorbent assay-reactive blood donors.  相似文献   
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