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1.
It was shown that Dacarbazine and other triazene compounds render murine leukemias highly immunogenic and susceptible to natural immunity (NI). In addition a pilot clinical study revealed that Dacarbazine can be cytotoxic for bone marrow blasts in patients with acute non-lymphoblastic leukemias through a mechanism that could be, at least in part, of immunological origin. However triazenes depress antigen-dependent responses and NI, whereas interferons, including interferon-beta (IFN), antagonize drug-induced impairment of NI. Therefore the complex interaction between triazenes and IFN on NI effector (i.e. NK) lymphocytes and human target lymphoblastoid cells has been investigated. the results show that: (a) EFN increases NK activity and antagonizes the depressive effects of methyl-triazene-benzoic acid (MTBA, an in vitro active triazene compound) on the NK function; (b) a lymphoblastoid cell line exposed to multiple in vitro treatments with MTBA, shows increased growth rate, augmented chemoresistance to MTBA, and higher susceptibility to NI than parental cells; (c) as expected IFN pretreatment down-regulates the susceptibility of lymphoblastoid cells to NK effectors; (d) however a net “therapeutic gain” was found if the overall influence of MTBA + IFN on target and effector cells is considered.  相似文献   
2.
Two new cases of primary mediastinal seminoma are presented and 126 cases from the literature are analysed. Radiotherapy, alone or combined with surgery, is thought by some authors to be the treatment of choice and the role of chemotherapy is uncertain. We propose a classification by which it is possible to compare various therapeutic approaches and to establish their value.  相似文献   
3.
The efficacy of alpha interferon (IFN-α) in the treatment of severe type II essential mixed cryoglobulinemia (EMC) has been reported previously. In some patients, the development of neutralizing antibodies to recombinant IFN-α (rIFN-α) can affect the clinical response achieved with rIFN-α; a second treatment with natural IFN-α preparations may reinduce the clinical response. In the present study the ability of leukocyte IFN (LeIFN) to restore the response was investigated from a pharmacodynamic viewpoint. Specifically, the pharmacodynamic profiles of different IFN-α preparations were studied by measuring the serum neopterin levels and the levels of expression of protein MxA mRNA in in vivo peripheral blood mononuclear cells in two patients with EMC whose resistance to rIFN-α2a treatment increased concomitantly with the development of neutralizing antibodies. These markers were measured before injection and at 24 and 48 h after a single injection of rIFN-α2a, consensus IFN [(C)IFN], or LeIFN. No increase or only a slight increase in MxA mRNA levels was detectable after administration of rIFN-α2a or (C)IFN, whereas a significant increase (≥10-fold) in MxA mRNA expression was recorded following administration of LeIFN. The neutralizing antibodies to rIFN-α2a cross-react with (C)IFN. Sera from these patients neutralized most but not all of the subtypes present in the natural IFN-α (LeIFN) mixture, and no significant increase in neopterin levels was observed after these patients were switched to LeIFN treatment. In summary, the data demonstrate that the problem of neutralizing antibodies still exists and that LeIFN may induce an increase in the level of MxA mRNA expression but not an increase in neopterin levels in patients who are resistant to treatment with rIFN-α2a or (C)IFN.  相似文献   
4.
The frequencies of anti-interferon-beta (IFN-beta) antibody development reported to date in patients treated with different IFN-beta preparations are not readily comparable mainly because of differences in underlying diseases and assay methods. Thus, the frequency of neutralizing antibody (NAb) and binding antibody (BAb) development was analyzed in a sample of sera derived from a homogeneous group of relapsing-remitting multiple sclerosis (RRMS) patients treated with different IFN-beta preparations. The frequency of developing NAb and BAb to IFN-beta varied according to the IFN-beta given. Specifically, the NAb seroconversion frequency was significantly higher in patients treated with Betaferon, Schering AG, Berlin, Germany (31.3%) than in patients treated with both preparations of recombinant IFN-beta 1a (Rebif, Serono, Geneva, Switzerland [7.4%] or Avonex, Biogen, Cambridge, MA [6.3%]). Analysis of BAb seroconversion frequency in the same patients revealed that different IFN-beta preparations may also have different capability to induce BAb development and that BAb are produced during IFN-beta therapy at a significantly higher rate than NAb. Our main conclusion is that different human IFN-beta preparations may possess different immunogenicities, leading to varying frequency of development of antibody to IFN-beta in RRMS.  相似文献   
5.
We conducted a serologic survey among dogs and cats in Italy to detect antibodies against severe acute respiratory syndrome virus 2 (SARS-CoV-2). We found that SARS-CoV-2 seroprevalence was higher among cats (16.2%) than dogs (2.3%). In addition, seroprevalence was higher among animals living in close contact with SARS-CoV-2–positive owners.  相似文献   
6.
This study aimed to evaluate the efficacy of amikacine and ceftazidime as an empirical antibiotic therapy for neutropenic patients affected by haematological neoplasms and to investigate the presence of prognostic features suggesting a poor outcome with this antibiotic combination at the onset of infection. This could allow the identification of subgroups of patients with a low rate of response to amikacin/ceftazidime therapy; in these patients different initial empirical therapy may be indicated. The study population comprised 166 severely neutropenic (absolute neutrophil count below 500/l) oncohaematological patients with fever or clinical signs of infection. Multivariate analysis confirmed four negative prognostic factors: 3 or more days of hospitalization at the onset of an infectious episode, a diagnosis of acute myeloid leukaemia, a haematological disease status different from complete remission, the presence of pneumonia. Depending on how many factors are present, cases can be stratified into three groups, of significantly different prognosis: favourable (0 or 1 factor) 76% success; intermediate (2 factors) 52% success; unfavourable (3 or 4 factors) 19% success. At the onset of an infectious episode a subgroup of patients with a very low response rate to empirical amikacin/ceftazidime antibiotic therapy is identifiable, for whom a different therapy is indicated. Because of the high rate of proven or probable fungal infections in this group, the immediate administration of a systemic antifungal therapy, in addition to antibacterial agents, could be considered in these high-risk patients. Studies should be specifically addressed to evaluating a stratification of empirical antibiotic therapy according to risk factors present at the onset of infection.  相似文献   
7.
PURPOSE: Imatinib (Glivec) is a potent inhibitor of bcr/abl, an oncogenic fusion protein that causes chronic myelogenous leukemia (CML). alpha1 acid glycoprotein (AGP) binds to imatinib with high affinity and inhibits imatinib activity in vitro and in vivo in an animal model. A pharmacokinetics analysis of imatinib was undertaken in CML patients. EXPERIMENTAL DESIGN: Imatinib plasma concentrations were measured in 19 CML patients treated with imatinib (400 or 600 mg/day). Five patients received a concomitant short-term course of clindamycin (CLI). RESULTS: A positive correlation between AGP and imatinib plasma levels was observed. CLI administration decreased imatinib plasma concentrations, evaluated as area under the curve (AUC) and peak concentrations (C(max)). The effects of a bolus of CLI was studied in three patients on imatinib 23 h after the last imatinib dose. Within 5-10 min in three of three cases, CLI caused a decrease in imatinib plasma concentrations of 2.6-, 2.7-, and 4.7-fold, respectively. In vitro experiments using fresh blasts from CML patients showed that AGP, at concentrations observed in the patients, decreased imatinib intracellular concentrations up to 10 times and blocked imatinib activity. The incubation with CLI restored imatinib intracellular concentrations and biological activity. CONCLUSION: AGP exerts significant effects of the pharmacokinetics, plasma concentrations, and intracellular distribution of imatinib in CML patients; these data indicate that plasma imatinib levels represent unreliable indicators of the cellular concentrations of this molecule.  相似文献   
8.
In this study, 3-D non-linear ultrasound simulations and experimental measurements were used to estimate the range of in situ pressures that can occur during transcutaneous abdominal imaging and to identify the sources of error when estimating in situ peak rarefaction pressures (PRPs) using linear derating, as specified by the mechanical index (MI) guideline. Using simulations, it was found that, for a large transmit aperture (F/1.5), MI consistently over-estimated in situ PRP by 20%–48% primarily owing to phase aberration. For a medium transmit aperture (F/3), the MI accurately estimated the in situ PRP to within 8%. For a small transmit aperture (F/5), MI consistently underestimated the in situ PRP by 32%–50%, with peak locations occurring 1–2 cm before the focal depth, often within the body wall itself. The large variability across body wall samples and focal configurations demonstrates the limitations of the simplified linear derating scheme. The results suggest that patient-specific in situ PRP estimation would allow for increases in transmit pressures, particularly for tightly focused beams, to improve diagnostic image quality while ensuring patient safety.  相似文献   
9.
10.
BackgroundEpidemiological evidence suggests that anti-inflammatory and immunomodulatory properties of statins may reduce the risk of infections and infection-related complications.ObjectiveWe aimed to assess the impact of prior statin use on coronavirus disease (COVID-19) severity and mortality.MethodsIn this observational multicenter study, consecutive patients hospitalized for COVID-19 were enrolled. In-hospital mortality and severity of COVID-19 assessed with National Early Warning Score (NEWS) were deemed primary and secondary outcomes, respectively. Propensity score (PS) matching was used to obtain balanced cohorts.ResultsAmong 842 patients enrolled, 179 (21%) were treated with statins before admission. Statin patients showed more comorbidities and more severe COVID-19 (NEWS 4 [IQR 2–6] vs 3 [IQR 2–5], p < 0.001). Despite having similar rates of intensive care unit admission, noninvasive ventilation, and mechanical ventilation, statin users appeared to show higher mortality rates. After balancing pre-existing relevant clinical conditions that could affect COVID-19 prognosis with PS matching, statin therapy confirmed its association with a more severe disease (NEWS ≥5 61% vs. 48%, p = 0.025) but not with in-hospital mortality (26% vs. 28%, p = 0.185). At univariate logistic regression analysis, statin use was confirmed not to be associated with mortality (OR 0.901; 95% CI: 0.537 to 1.51; p = 0.692) and to be associated with a more severe disease (NEWS≥5 OR 1.7; 95% CI 1.067–2.71; p = 0.026).ConclusionsOur results did not confirm the supposed favorable effects of statin therapy on COVID-19 outcomes. Conversely, they suggest that statin use should be considered as a proxy of underlying comorbidities, which indeed expose to increased risks of more severe COVID-19.  相似文献   
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