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排序方式: 共有416条查询结果,搜索用时 15 毫秒
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Adherence of L1210 murine leukemia cells to sephacryl- aminopropylcobalamin beads treated with transcobalamin-II 总被引:1,自引:0,他引:1
Sephacryl beads containing an immobilized aminopropylcobalamin- transcobalamin-II complex serve as foci for the adherence of L1210 murine leukemia cells. Bead-cell interaction does not occur when (A) nonderivatized beads are used; (B) transcobalamin-II is omitted or presaturated with cyanocobalamin in the preparation of the bead complex; (C) intrinsic factor replaces transcobalamin-II; and (D) the complex is removed from beads by photolysis. These observations suggest that adherence results from the ability of transcobalamin-II to form a bridge between immobilized cobalamin on the bead and receptors in the plasma membrane of the cell. 相似文献
34.
Hematopoietic progenitors and interleukin-3-dependent cell lines synthesize histamine in response to calcium ionophore 总被引:1,自引:1,他引:1
The calcium ionophore A23187 promotes histamine synthesis in murine bone marrow cells by increasing the expression of mRNA encoding histidine decarboxylase (HDC), the histamine-forming enzyme. The cells responsible for this biological activity copurify with hematopoietic progenitors in terms of density, light scatter characteristics, and rhodamine retention, similar to interleukin (IL) 3-induced histamine- producing cells. Yet, the effect of calcium ionophore is not mediated by IL-3. The most purified rhodamine-bright bone marrow subset contains 80% cells that respond to calcium ionophore by increased HDC mRNA expression. This high frequency makes the involvement of one particular progenitor subset in histamine synthesis unlikely. The finding that all IL-3-dependent cell lines tested so far exhibit increased histamine production and HDC mRNA expression in response to calcium influx lends further support to this notion. Cell lines requiring other growth factors or proliferating spontaneously lack this ability. Finally, it should be noted that IL-3-dependent cell lines do not produce histamine in response to their growth factor. It might, therefore, be suggested that the pathway transducing the signal for increased histamine synthesis after IL-3 receptor binding in normal hematopoietic progenitors is modified in these cell lines. 相似文献
35.
Ahmed A.M. Abdel-Hamid Alaa El-Din L. Firgany Yaser Mesbah Mona FM Soliman 《Experimental and molecular pathology》2017,102(2):284-289
Background: ART is steadily performed for infertility cases and most of the previous researches have focused on complicated pregnancies. Nonetheless, few ones have concerned with placenta of ART in non-complicated pregnancies.Objectives: To investigate the expression of angiopoietins (ANG) and their receptor, TIE-2, in placenta of full-term non-complicated pregnancies having ART (n = 28) versus those with spontaneous conception (n = 28) together with the histological as well as morphometric analysis.Results: While no prominent changes were noticed in the histological structure of the placenta ART pregnancies, it showed a significant decrease (p < 0.05) in the percentage of syncytial area and numbers of syncytial knots with insignificant reduction in the placental villous area. Vascular changes in the form of significant decrease (p < 0.05) in the chorionic vessel diameter and significant increase (p < 0.05) in percentage of vessel area were detected in the ART placenta. In addition, the levels ANG-1, ANG-2 and TIE-2 were significantly increased (p < 0.05) in the ART placentas compared with those of SC.Conclusions: We demonstrated that there is an altered expression of angiopoietins accompanying the morphometric changes occurring in placenta of ART pregnancies. These changes may indicate vascular and cellular adaptation mechanism for a potential subclinical hypoxia in placenta of ART even in non-complicated pregnancies. 相似文献
36.
RM Nobre ALR Ribeiro SM Alves-Junior FM Tuji M das G Rodrigues Pinheiro LR Pinheiro JJV Pinheiro 《Dento maxillo facial radiology》2012,41(7):541-547
Objectives
A wide variety of manifestations is presented in patients with Gaucher''s disease (GD), including bone, haematology and visceral disturbances. This study was conducted to ascertain the main maxillofacial abnormalities by means of clinical survey, panoramic and cone beam CT (CBCT); to compare the patient''s group with an age–sex matched control group; and to correlate clinical and radiological data.Methods
Ten patients previously diagnosed with GD were submitted to clinical and radiological surveys (CBCT and panoramic radiographs). The examination consisted of anamnesis, extra- and intraoral examinations and analyses of each patient''s records. Imaging data were collected from the point of view of 3 observers, and the results compared with a healthy group (20 individuals) by means of statistical analysis (Fisher''s exact test).Results
Gaucher patients had significantly more manifestations than otherwise healthy carriers. The most prevalent findings were enlarged marrow spaces, generalized osteopenia and effacement of jaw structures (mandibular canal, lamina dura and mental foramen). Here we describe a case in which thickening of the maxillary sinus mucosa was observed on CBCT rather than opacification of the sinus as seen on panoramic radiographs. Pathological fractures, root resorption and delay on tooth eruption were not observed.Conclusions
A poor relationship could be observed between clinical and radiological data. Patients showed important bone manifestations, which require careful diagnostic and surgical planning whenever necessary. Although panoramic radiographs have shown significant differences, CBCT is more effective in pointing out differences between patients and a control group, thus showing it as an important tool for evaluation of Gaucher patients. 相似文献37.
Leukemic cell growth in SCID mice as a predictor of relapse in high- risk B-lineage acute lymphoblastic leukemia 总被引:3,自引:2,他引:3
Uckun FM; Sather H; Reaman G; Shuster J; Land V; Trigg M; Gunther R; Chelstrom L; Bleyer A; Gaynon P 《Blood》1995,85(4):873-878
Mice with severe combined immunodeficiency (SCID) provide a model system to examine the in vivo homing, engraftment, and growth patterns of normal and malignant human hematopoietic cells. The relation between leukemic cell growth in this model and the treatment outcome in patients from whom cells were derived has not been established. Leukemic cells from 42 children with newly diagnosed high-risk B- lineage acute lymphoblastic leukemia were inoculated intravenously into CB.17 SCID mice. Mice were killed at 12 weeks or when they became moribund as a result of disseminated leukemia. All mice were necropsied and subjected to a series of laboratory studies to assess their burden of human leukemic cells. Twenty-three patients whose leukemic cells caused histopathologically detectable leukemia in SCID mice had a significantly higher relapse rate than the 19 patients whose leukemic cells did not (estimated 5-year event-free survival: 29.5% v 94.7%; 95% confidence intervals, 11.2% to 50.7% v 68.1% to 99.2%; P < .0001 by log- rank test). The occurrence of overt leukemia in SCID mice was was a highly significant predictor of patient relapse. The estimated instantaneous risk of relapse for patients whose leukemic cells caused overt leukemia in SCID mice was 21.5-fold greater than that for the remaining patients. Thus, growth of human leukemic cells in SCID mice is a strong and independent predictor of relapse in patients with newly diagnosed high-risk B-lineage acute lymphoblastic leukemia. 相似文献
38.
Monoclonal antibody T101 in T cell malignancies: a clinical, pharmacokinetic, and immunologic correlation 总被引:2,自引:0,他引:2
Bertram JH; Gill PS; Levine AM; Boquiren D; Hoffman FM; Meyer P; Mitchell MS 《Blood》1986,68(3):752-761
Eight patients with cutaneous T cell lymphomas (CTCL) and five with various other T cell malignancies were treated with mouse monoclonal antibody (MoAb) T101. Doses of 1 to 500 mg were administered weekly over a two-hour period and resulted in one complete remission (convoluted T cell lymphoma) and one partial remission (CTCL). Remission duration was 6 weeks and 3 months, respectively. Frequent toxicities were pruritus, hives, flushing, and shortness of breath. Supraventricular arrhythmias and blood pressure instability were also observed. Complete targeting of peripheral blood T cells was achieved with 1 mg of MoAb in the nonleukemic patients (WBC less than 10,000/microL), and free, bioavailable antibody was present at the next (10-mg) dose level. Even higher doses resulted in substantial antibody excess that persisted for as long as 6 weeks. Serum concentrations of MoAb decreased with increasing number of peripheral blood T cells, and 25 to 35 mg of T101 were required for induction of antibody excess in leukemic patients. Excess antibody induced antigenic modulation, which was of consequence only if MoAb excess persisted to the next treatment. In the original treatment, the rapidly administered MoAb was able to target and remove peripheral blood T cells before the development of antigenic modulation. Antimouse antibodies developed in three patients. Their presence rendered further therapy ineffective and was associated with an anaphylactic reaction in one patient. Development of these antibodies could not be predicted by lymphoproliferative assays. In these assays, however, the T101 protein strongly stimulated the mononuclear cells of the patient who reached the only complete remission of this trial. Immunologic stimulation by the MoAb thus might have played a role in this patient's antitumor response. In summary, therapy with MoAb T101 was specific but only modestly efficacious. Rapid infusion of nonmodulating doses of antibody provided excellent targeting and removal of peripheral blood T cells and might be a valid approach in future trials with immunoconjugated T101. 相似文献
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