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651.
652.
653.
高血糖能加重急性脑梗死的脑损伤。研究者测试了急性脑梗死时静脉胰岛素强化治疗与普通护理相比的可靠性和耐受性,开展了一个12h内脑梗死的随机多中心双盲实验,其血糖水平≥8.3mmol/L,美国国立卫生研究所脑卒中评分(NIHSS)在3~22分。患者以2:1的比例被随机分配至连续性静脉输注胰岛素或规定每日4次皮下注射胰岛素的强化治疗组。强化治疗组的目标血糖水平〈7.2mmol/L,  相似文献   
654.
A 72-year-old man was hospitalized for exacerbation of chronic obstructive pulmonary disease and was treated with oral prednisone and 7 days of moxifloxacin. Five days after completing the antibiotic course, he developed watery diarrhea and diffuse, crampy abdominal pain. On presentation he was afebrile, and abdominal examination revealed diffuse tenderness without peritoneal signs. Stool tested positive for Clostridium difficile toxin A by enzyme-linked immunosorbent assay. Despite starting oral metronidazole, the patient developed a fever of 101.2 degrees F 36 hours after his initial episode of diarrhea, 12 hours after admission. His abdominal pain intensified and became localized to the right and left lower quadrants. Computed tomography scan revealed both a thickened cecal wall and an edematous appendix with ileocecal stranding consistent with appendicitis. Appendectomy was performed, and the appendix was found to be suppurative in appearance and nonperforated. The cecum had mild edema and erythema, whereas the colon and rectum were grossly unaffected. Pathology examination revealed exudative material in the appendiceal lumen and a diffuse transmural inflammatory cell infiltrate. The patient had an uneventful recovery and continued to improve on oral metronidazole. Although Clostridium difficile colitis and appendicitis are each very common independently, C. difficile as an etiology of appendicitis is exceedingly rare. A review of the literature revealed 2 prior cases. We speculate that this association is underdiagnosed, because milder cases might respond to antibiotic therapy alone, and severe cases might involve the entire colon and require total colectomy. In each scenario, the involvement of the appendix might be overlooked.  相似文献   
655.
The regulatory function of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) on granulocyte production in vivo was evaluated in an autologous bone marrow transplantation model using rhesus monkeys. Monkeys were exposed to 9.0 Gy total body irradiation and then transplanted with 5.0 x 10(7) low-density bone marrow cells/kg. Alzet miniosmotic pumps were subcutaneously implanted to deliver rhGM-CSF at a rate of 50,400 U/kg/d. Minipumps, containing either rhGM-CSF or saline, were implanted between zero and five days after transplantation for seven days. Kinetic recoveries of peripheral blood cells after either saline or rhGM-CSF treatment were compared. Treatment with rhGM-CSF accelerated the recovery of neutrophils. Neutrophils in rhGM-CSF-treated animals recovered to 80% (3.4 x 10(3)/mm3) pre-irradiation control levels by day 20, in comparison with only 33% (0.9 x 10(3)/mm3) recovery for saline control monkeys. In addition, the recovery of neutrophils was enhanced over that of the controls, reaching 140% v 70% on day 30. Another prominent feature of rhGM-CSF-treated monkeys was the accelerated recovery of platelets, reaching near 50% normal levels by day 24 in comparison with 20% of normal levels for controls. The infusion of rhGM-CSF was shown to be an effective regulator of early hematopoietic regeneration, leading to the accelerated recovery of both neutrophils and platelets and then providing a consistent sustained increase of neutrophils even in the absence of rhGM-CSF.  相似文献   
656.
Rowley  SD; Bensinger  WI; Gooley  TA; Buckner  CD 《Blood》1994,83(9):2731-2736
The effects of cell concentration during cryopreservation on bone marrow (BM) or peripheral blood (PB)-derived hematopoietic progenitor cells have not been described. The much greater numbers of cells harvested for autologous PB stem cell (PBSC) transplantation requires that the cells be frozen at higher cell concentrations, or in much greater volumes, compared with BM. We cryopreserved 108 PBSC collections from 30 patients at an average (+/- SD) cell concentration of 3.7 +/- 1.9 x 10(8) nucleated cells per mL in 127 +/- 45 mL. The proportion of mononuclear cells was 52.9% +/- 27.2%. The products also contained 2.9 +/- 2.1 x 10(9) platelets/mL and an average red cell proportion of 12.9% +/- 7.2%. The nucleated cell recovery after thawing was 75.4% +/- 13.0%. The nucleated cell concentration during freezing was not predictive for the postthaw recoveries of nucleated cells (P = .38), granulocyte-macrophage colony-forming unit (P = .06) or CD34+ cells (P = .54), or for the viability of mononuclear cells (P = .81). The platelet and red cell concentrations similarly were not predictive for these endpoints. Samples (3 BM, 7 PBSC) from 10 patients were simultaneously cryopreserved at two-fold, and from 5 additional patients (PBSC) at 6- to 24-fold differing cell concentrations. A lower recovery of erythroid burst forming unit was found for samples frozen at higher cell concentrations (P = .04), but no significant differences were found in the other endpoints listed above. The average cell concentration during freezing for each patient's PBSC collections (n = 34 patients) did not predict time to achieve a PB count of > 500 granulocytes/microL (P = .51) or platelet transfusion independence (P = .39). Patients achieved these endpoints of engraftment at medians of 12 and 13 days, respectively. The infusion of these products was generally well tolerated. Similarly, the cell concentration at which BM cells were frozen did not predict for the duration of granulocyte (P = .63) or platelet (P = .36) aplasias for 54 patients undergoing autologous BM transplantation. These data suggest that PBSC or BM cells collected for transplantation may be cryopreserved at very high cell concentrations without loss of engraftment potential or undue infusion-related toxicity.  相似文献   
657.
Ultraviolet-B (UV-B) irradiation of antigen presenting cells (APCs) modifies their allogenecity, resulting in inhibition of the proliferative response of T cells in mixed lymphocyte reaction (MLR). Costimulation by the CD28 ligand CD80 (B7/B7-1) and CD86 (B70/B7-2) plays an important role during T-cell proliferation by augmenting synthesis of interleukin-2 (IL-2) and other cytokines. In this study, we demonstrated induced expression of both CD80 and CD86 during allogeneic MLR, though human freshly isolated monocytes express CD86 constitutively with a much lower level of CD80. A monoclonal antibody (MoAb) against CD86, but not CD80, efficiently inhibited allogeneic T- cell proliferative responses stimulated with highly purified monocytes. UV-B exposure (0 to 1,000 J/m2) of monocytes inhibited the proliferation of T lymphocytes in MLR in a dose-dependent manner. Flow cytometric analysis showed that UV-B exposure of monocytes impaired the constitutive expression of CD54 (intercellular adhesion molecule-1) by 24 hours after irradiation, but the effect on CD86 was relatively less. The surface expression of CD80, CD86, CD54, and HLA-DR on monocytes was further augmented by interferon (IFN)-gamma; this cytokine-induced expression was dose-dependently reduced by UV-B irradiation. Similarly, the upregulation of these molecules following allogeneic MLR was downregulated by UV-B irradiation. UV-B irradiation of monocytes inhibited the expression of IL-2 mRNA in monocyte-stimulated allogeneic MLR. In contrast, the addition of anti-CD28 MoAb at the onset of MLR prevented, at least partially, the reduction of IL-2 mRNA. These results strongly suggest that the impairment of inducible expression of CD86 and CD80 may contribute to the reduced MLR response following exposure of monocytes of UV-B.  相似文献   
658.
<正>We studied effects of nutrient quercetin on cytochromes’Р450 1А(CYP1A)activities(measured spectrofluorimetrically using 7-ethoxy-resorufin for CYP1A1 and 7-methoxy-resorufin for CYP1A2 as substrates),on mR NA levels(measured by RT-PCR),and on DNA-binding activities(evaluated by an electrophoretic mobility shift assay)of proteins regulating CYP1A expression in untreated and benzo(α)pyrene(Ba P)-treated rats.Wistar rats  相似文献   
659.
目的对中心注射室护理工作的满意度进行调查,了解影响医院护理工作满意度的因素。方法选择2011年1~12月在中心注射室接受治疗的患者252例为研究对象,采用问卷法对患者进行调查,并分析影响注射室护理工作满意度的因素。结果接受调查的住院患者中,患者的满意度得分与患者的年龄、受教育程度、收入水平、住院科室、住院天数以及是否手术存在相关性。结论护理人员应重视和加强护理工作质量和效率,提高临床患者对护理工作的满意程度。  相似文献   
660.

Background  

Exosomes are released from multiple cell types, contain protein and RNA species, and have been exploited as a novel reservoir for disease biomarker discovery. They can transfer information between cells and may cause pathology, for example, a role for exosomes has been proposed in the pathophysiology of Alzheimer's disease. Although studied in several biofluids, exosomes have not been extensively studied in the cerebrospinal fluid (CSF) from humans. The objective of this study was to determine: 1) whether human CSF contains exosomes and 2) the variability in exosomal protein content across individuals.  相似文献   
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