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71.
BACKGROUND AND OBJECTIVES: Arsenic trioxide (ATO) has been reported to be a safe and effective treatment for relapsed acute promyelocytic leukemia (APL). The aim of this study was to evaluate the efficacy and toxicity as well as the eligibility to stem cell transplantation (SCT) in a series of 7 patients with relapsing APL, managed with ATO. DESIGN AND METHODS: Seven patients with relapsing APL while on maintenance treatment with all-trans-retinoic acid (ATRA) or who were ATRA refractory-received ATO at a dose of 10 mg daily by 2-hour intravenous infusion until complete remission (CR). After consolidation chemotherapy, patients were programmed to receive autologous or allogeneic stem cell transplantation (SCT) according to donor availability. The median age of the patients was 55 (21-71) years: 2 patients presented with concomitant extramedullary relapse. RESULTS: Six patients (86%) achieved CR after a median of 35 ATO doses (20-49) with negligible toxicity; one patient died from pneumonia. After consolidation with a four-day course of cytarabine at 1 g/m2 and mitoxantrone 6 mg/m2, two patients underwent allogeneic SCT, two received PML/RARa negative autologous peripheral blood stem cells collected after consolidation plus granulocyte colony-stimulating factor, one failed mobilization and received a second consolidation course. One elderly patient refused further treatment and relapsed 6 months later. After a median follow-up of 15 months from CR2 achievement, 5 patients are alive in continuous CR. INTERPRETATION AND CONCLUSIONS: The high CR rate and the mild toxicity confirm that ATO represents a valid alternative to salvage chemotherapy for patients relapsing while on ATRA treatment or who are ATRA-refractory. Allogeneic or autologous SCT after ATO-induced CR is feasible in the majority of patients.  相似文献   
72.
Molecular histogenesis of plasmablastic lymphoma of the oral cavity   总被引:4,自引:0,他引:4  
Plasmablastic lymphoma (PBL) of the oral cavity is an aggressive B-cell lymphoma associated with human immunodeficiency virus infection. Although the lymphoma phenotype is consistent with late B-cell maturation, the molecular histogenesis of PBL is unknown. We investigated PBL of the oral cavity (n = 12) for mutations of immunoglobulin variable heavy chain (IgVH) and BCL-6 genes, which are acquired by B cells at the time of germinal centre (GC) transit, and for expression of BCL-6, MUM-1 and CD138, which distinguish GC B cells from post-GC B cells. Somatic IgVH hypermutation occurred in 4/10 PBL whereas 6/10 PBL displayed germline IgVH genes. Among PBL carrying hypermutated IgVH genes, the pattern of IgVH mutations was consistent with antigen stimulation in two cases. Mutations of the BCL-6 gene were restricted to 1/12 patients with PBL of the oral cavity. All cases of PBL of the oral cavity displayed the BCL-6-/MUM-1+/CD138+ phenotype that is consistent with late stage of B-cell differentiation. Overall, these data indicate that, despite a common phenotype and an apparently similar degree of differentiation, PBL of the oral cavity are characterized by histogenetic heterogeneity. A subset of PBL of the oral cavity carried the molecular clues of GC transit and conceivably originated from a B-cell subset corresponding to post-GC B cells. Conversely, another fraction of these lymphomas were devoid of somatic IgVH mutations and appeared to originate from naive B cells that have undergone preterminal differentiation independent of GC transit.  相似文献   
73.
Effects of beta-endorphin and met-enkephalin on platelet activity   总被引:2,自引:0,他引:2  
In the present study, beta-endorphin and met-enkephalin were tested for their antiplatelet activity in human platelet-rich plasma (PRP). Blood samples were obtained from 15 healthy subjects. The results of the study show that these two endogenous opioids (200 pg/ml final concentration) reduce platelet aggregation when it is induced by ADP at low dose (0.5 microM). It is likely due to conformational changes on the platelet membrane that cause a non-specific decreased susceptibility to platelet-aggregating agonists.  相似文献   
74.
There have been few reports of a response to dasatinib or nilotinib after failure of two prior sequential tyrosine kinase inhibitors. We report the outcome of 82 chronic phase patients who received nilotinib or dasatinib as third-line alternative tyrosine kinase inhibitor therapy. Thirty-four patients failed to respond to nilotinib and were started on dasatinib as third-line tyrosine kinase inhibitor therapy while 48 patients were switched to nilotinib after dasatinib failure. Overall, we obtained a cytogenetic response in 32 of 82 patients and major molecular response in 13 patients; disease progression occurred in 12 patients. At last follow up, 70 patients (85.4%) were alive with a median overall survival of 46 months. Our results show that third-line tyrosine kinase inhibitor therapy in chronic myeloid leukemia patients after failure of two prior sequential tyrosine kinase inhibitors may induce a response that, in some instances, could prolong overall survival and affect event-free survival.  相似文献   
75.
Serum and cerebrospinal fluid (CSF) from patients with multiple sclerosis (MS), patients with other (non-inflammatory) neurological diseases (OND), patients with non-inflammatory non-neurological diseases, and normal controls were assayed for lymphocyte activiting factor (LAF) activity by thymocyte costimulation. LAF activity was detected in normal control sera, which did not differ significantly in this respect from MS or OND patient sera. Not were there significant differences by stage of MS (chronic progressive MS, MS in relapse and MS in remission) or between MS patients and the non-inflammatory non-neurological controls. Almost all the CFSs assayed presented lower values than did the corresponding sera. Serum and CSF after fractionation showed no significant increase in LAF activity except in the 2 MS patients in remission. From these data it may be assumed that LAF activity does not necessarily correspond to the clinical phase of MS. The possible role of LAF activity as a marker of MS progression has yet to be determined.
Sommario La capacità di co-stimolare la proliferazione timocitaria (attività LAF) è stata valutata nel siero e nel liquor di pazienti con sclerosi a placche e con altre malattie neurologiche non infiammatorie. La valutazione è stata anche fatta in pazienti senza malattie neurologiche né infiammatorie, considerati come controlli ed in soggetti normali. I sieri di questi ultimi presentavano un certo grado di attività LAF e non è stata trovata alcuna differenza significativa tra questo gruppo e tra i sieri dei pazienti con sclerosi a placche e quelli dei pazienti con altre malattie neurologiche. Inoltre, non vi era alcuna differenza significativa tra i sieri dei pazienti con sclerosi a placche in vari stadi della malattia. Anche nei campioni di liquor non è stata trovata alcuna differenza significativa e comunque quasi tutti i liquor esaminati presentavano una minore attività LAF dei rispettivi sieri. L'attività LAF dopo frazionamento non aumentava significativamente ad eccezione dei due sieri di pazienti con sclerosi a placche in remissione. Alla luce di questi dati si può concludere che l'attività LAF non è correlata necessariamente alla fase clinica della sclerosi a placche.
  相似文献   
76.
Primary effusions presenting as the sole lymphoma localization are also known as body-cavity-based-lymphoma (BCBL), and have been shown to carry Kaposi's sarcoma herpesvirus (KSHV) DNA sequences. The aim of this study was a comparative analysis of the clinical, pathologic and molecular features of BCBL and lymphomatous effusions secondary to tissue-based lymphomas occurring both in the general population and in HIV-1-infected individuals. All the lymphomatous effusion samples (seven AIDS-related and nine AIDS-unrelated) were subjected to an identical multiparameter investigation, including collection of clinical data, analysis of morphology and immunophenotype, as well as the study of viral sequences and genetic lesions. In six cases defined as BCBL (four AIDS-related and two AIDS-unrelated), the patients exhibited exclusive or predominant involvement of the body cavities. BCBL tended to display indeterminate phenotypes (4/6), whereas all AIDS-related and AIDS-unrelated lymphomatous effusions secondary to tissue-based lymphomas consistently expressed B-cell phenotype. Detection of KSHV DNA sequences was restricted to cases of BCBL (3/4 AIDS-related and 1/2 AIDS-unrelated), whereas EBV association (3/4) and expression of EBV-encoded antigens (LMP-1, 2/3; EBNA-2, 1/3) were confined to the AIDS-related BCBL. Overall, our results confirm that both AIDS-related and AIDS-unrelated BCBL preferentially associate with peculiar clinical, immunophenotypic and molecular features among lymphomatous effusions and therefore should be singled out as a specific clinico-pathologic entity.  相似文献   
77.
We describe two cases of patients with Steinert’s dystrophy or myotonic dystrophy type 1 (DM1) who presented with frequent respiratory exacerbations and pneumonia. They did not report any risk factors for asthma, allergy, bronchopathy or dysphagia in their history. The Videofluoroscopic swallow study test allowed to highlight post-swallowing aspiration phenomena responsible for respiratory exacerbations.Key words: dysphagia, Steinert disease, respiratory exacerbation  相似文献   
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Temporal lobe epilepsy often manifests months or even years after an initial epileptogenic insult (e.g., stroke, trauma, status epilepticus) and, therefore, may be preventable. However, no such preventive treatment is currently available. Aim of this study was to test an antioxidant agent, 7,8-dihydroxyflavone (7,8-DHF), that is well tolerated and effective in preclinical models of many neurological disorders, as an anti-epileptogenic drug. However, 7,8-DHF also acts as a TrkB receptor agonist and, based on the literature, this effect may imply an anti- or a pro-epileptogenic effect. We found that low- (5 mg/kg), but not high-dose 7,8-DHF (10 mg/kg) can exert strong anti-epileptogenic effects in the lithium-pilocarpine model (i.e., highly significant reduction in the frequency of spontaneous seizures and in the time to first seizure after status epilepticus). The mechanism of these different dose-related effects remains to be elucidated. Nonetheless, considering its excellent safety profile and antioxidant properties, as well as its putative effects on TrkB receptors, 7,8-DHF represents an interesting template for the development of effective and well-tolerated anti-epileptogenic drugs.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-022-01299-4.  相似文献   
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