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61.
62.

Background  

The Bielefeld Partnership Expectations Questionnaire (BFPE) is a tool to assess attachment in the romantic relationships of adults. The attachment styles are operationalized as configuration patterns of scale scores. While convergent validity has already been investigated, discriminant validity is still lacking confirmation.  相似文献   
63.
BACKGROUND: Patients with acute myeloid leukemia (AML) with hyperleukocytosis of at least 100 x 10(9) per L are at high risk of early death due to pulmonary or cerebral leukostasis. Although the efficacy of leukapheresis in terms of prompt cytoreduction is generally accepted, published data regarding the clinical value of immediate therapeutic leukapheresis are limited and conflicting. STUDY DESIGN AND METHODS: To determine whether leukapheresis has a favorable impact on early mortality, the clinical course of 53 newly diagnosed patients with AML and hyperleukocytosis admitted between 1995 and 2005 was analyzed retrospectively. Before August 2001, 28 patients received chemotherapy without leukoreduction (Cohort A). Thereafter, all AML patients with hyperleukocytosis were scheduled to receive leukapheresis, which was performed in 25 patients (Cohort B). RESULTS: There were no procedure-related adverse events. By Day 21 of therapy, 13 of 53 patients had died, resulting in an overall early death rate of 25 percent. In a multivariate logistic regression model, patients in Cohort B had a significantly lower risk of early death than patients in Cohort A (16% vs. 32%, respectively; p = 0.015). Dyspnea (p = 0.005), elevated creatinine (p = 0.028), and higher lactate dehydrogenase serum levels (p = 0.021) were independent risk factors for early death. With a median follow-up of 24.2 months, the overall survival was similar in both cohorts (Cohort A, 7.5; Cohort B, 6.5 months). Thus, leukapheresis had no impact on patients' long-term survivals. CONCLUSIONS: Our experience suggests that AML patients with hyperleukocytosis receiving leukapheresis had a significantly lower risk for early death by Day 21 than patients treated without leukapheresis. We therefore have adopted leukapheresis as a standard procedure in our department.  相似文献   
64.
In a pilot study high-dose melphalan (HD-Mel, 200 mg/m2) and autologous stem cell transplantation (ASCT) were administered to 14 patients (median age 52, range 29–60 years) with acute myeloid leukaemia (AML) in first relapse after a previous ASCT in first complete remission (n=11) or chemotherapy (n=3). A first cohort of five patients received HD-Mel as salvage therapy after a previous cycle of mitoxantrone, topotecan and cytarabine (MTC) had failed in four out of five patients, while a second cohort of nine patients received HD-Mel in untreated relapse. Thirteen (93%) of 14 patients achieved a second complete remission (CR2), including all four patients who had been refractory to MTC. No treatment-related mortality was observed after HD-Mel. Thirteen (93%) patients were able to proceed to a dose-reduced allogeneic stem cell transplantation (allo-SCT) from human-leucocyte-antigens-compatible unrelated (n=12) or sibling donors (n=1) in CR2 (n=11) or poor recovery/relapse (n=2) after a median of 2 (1.7–4.5) months following HD-Mel. Three MTC-refractory patients, but none of the upfront HD-Mel patients, died due to an allograft-related non-relapse cause. Nine patients are alive in CR2 after a median of 6 (2–49) months after HD-Mel and a median of 4 (0.6–47) months after a sequential allo-SCT. Although median follow-up is still short, the proportion of patients achieving a CR2, as well as of those proceeding to a subsequent reduced-intensity-conditioning-allo-SCT, is superior to those previously reported. Our results highly encourage to further investigate HD-Mel and ASCT as a promising salvage regimen for relapsed AML patients for whom autologous peripheral blood stem cells are available.  相似文献   
65.
Umbilical cord blood transplantation is applied as treatment for mainly pediatric patients with hematologic malignancies. The clinical results show a relatively low incidence of graft-versus-host disease and leukemia relapse. Since maternal cells traffic into the fetus during pregnancy, we questioned whether cord blood has the potential to generate cytotoxic T cells specific for the hematopoietic minor histocompatibility (H) antigen HA-1 that would support the graft-versus-leukemia effect. Here, we demonstrate the feasibility of ex vivo generation of minor H antigen HA-1-specific T cells from cord blood cells. Moreover, we observed pre-existing HA-1-specific T cells in cord blood samples. Both the circulating and the ex vivo-generated HA-1-specific T cells show specific and hematopoietic restricted lysis of human leukocyte antigen-A2(pos)/HA-1(pos) (HLA-A2(pos)/HA-1(pos)) target cells, including leukemic cells. The cord blood-derived HA-1-specific cytotoxic T cells are from child origin. Thus, the so-called naive cord blood can comprise cytotoxic T cells directed at the maternal minor H antigen HA-1. The apparent immunization status of cord blood may well contribute to the in vivo graft-versus-leukemia activity after transplantation. Moreover, since the fetus cannot be primed against Y chromosome-encoded minor H antigens, cord blood is an attractive stem cell source for male patients.  相似文献   
66.
Formation of toxic α-synuclein oligomers appears to be a key underlying pathological mechanism of synucleinopathies such as Parkinson’s disease or multiple system atrophy (MSA). Given that Epigallocatechin-gallate has been shown to inhibit α-synuclein aggregation, it might represent a causal treatment option. Therefore, we set out to evaluate the safety, tolerability and a potential disease-modifying effect of Epigallocatechin-gallate in patients with MSA after 48 weeks of treatment. Power calculation was performed on existing natural history data on the progression of the Unified MSA Rating Scale as primary readout parameter. To assess the efficacy of Epigallocatechin-gallate versus placebo regarding the reduction of disease progression measured during the study period (80 % power, 5 % p level, 50 % effect size) 36 patients per group are needed. Considering a drop-out rate of 20 % a total of 86 patients will be recruited in this multicentre study. These data provide a solid rationale to investigate whether supplementation of Epigallocatechin-gallate can delay the progression of the MSA-related disability.  相似文献   
67.
68.
The ability of bone marrow stroma to modulate hematopoietic progenitor cell expansion is of considerable interest for gene transfer strategies and transplantation of limited stem cell numbers. We compared the capacity of 2 murine stromal cell lines to affect the balance between maturation and proliferation of human CD34+ cells in short-term expansion cultures. In 7-day serum-free cultures, cytokine-induced amplification of granulocyte-macrophage colony-forming cells (CFC-GM), erythroid burst-forming units (BFU-E), and total cells was significantly increased by the presence of genetically engineered Sl/Sl and M2-10B4 stromal cells in a 1:1 ratio (Sl/M2 cells) compared with stroma-free cultures (P < .05). Sl/M2 cultures generated 21-fold more mature CD15+ cells than stroma-free cultures, without further amplifying the number of CD34+ cells. The addition of serum led to a further increase of CFC-GM, total cells, and CD15+ cells, whereas BFU-E were no longer maintained. Pure Sl/Sl stromal layers were likewise superior to stroma-free cultures in expansion of CD34+ cells and total cells when serum was present. However, the differentiation of CD34+ cells was less pronounced in Sl/Sl cultures compared with Sl/M2 layers, as demonstrated by a lower content of CD15+ cells. Neutralization experiments revealed differential contributions of Flt3 ligand and thrombopoietin to the support of total cell and CFC expansion by Sl/M2 and Sl/Sl stromal feeders.  相似文献   
69.
Residential self-selection is supposed to bias the relation between residential environments and physical activity, but empirical analyses are still rare. This study examines the association while simultaneously considering the effect of residential self-selection criteria. One thousand two hundred and forty-five German students were asked to report their physical activity, their perceived environment, and their reasons for choosing their neighbourhood. Structural equation modelling was employed. Reasons for choosing a neighbourhood were related to actual environmental characteristics. Utilitarian reasons were related to less physical activity, hedonic reasons were related to higher physical activity. The street network was related to higher physical activity independent of residential self-selection. Our results support the weight of both individual preferences and the street network on physical activity. The residential environment has an impact on people’s amount of physical activity regardless of their reasons for choosing a neighbourhood and should therefore be considered a resource in health prevention and promotion.  相似文献   
70.

Background

Myelodysplastic syndromes are a heterogeneous group of hematopoietic stem cell disorders with a high propensity to transform into acute myeloid leukemia. Heterozygous missense mutations in IDH1 at position R132 and in IDH2 at positions R140 and R172 have recently been reported in acute myeloid leukemia. However, little is known about the incidence and prognostic impact of IDH1 and IDH2 mutations in myelodysplastic syndromes.

Design and Methods

We examined 193 patients with myelodysplastic syndromes and 53 patients with acute myeloid leukemia arising from myelodysplastic syndromes for mutations in IDH1 (R132), IDH2 (R172 and R140), and NPM1 by direct sequencing.

Results

We found that mutations in IDH1 occurred with a frequency of 3.6% in myelodysplastic syndromes (7 mutations in 193 patients) and 7.5% in acute myeloid leukemia following myelodysplastic syndromes (4 mutations in 53 patients). Three mutations in codon R140 of IDH2 and one mutation in codon R172 were found in patients with acute myeloid leukemia following myelodysplastic syndromes (7.5%). No IDH2 R140 or R172 mutations were identified in patients with myelodysplastic syndromes. The presence of IDH1 mutations was associated with a shorter overall survival (HR 3.20; 95% CI 1.47–6.99) and a higher rate of transformation into acute myeloid leukemia (67% versus 28%, P=0.04). In multivariate analysis when considering karyotype, transfusion dependence and International Prognostic Scoring System score, IDH1 mutations remained an independent prognostic marker in myelodysplastic syndromes (HR 3.57; 95% CI 1.59–8.02; P=0.002).

Conclusions

These results suggest that IDH1 mutations are recurrent molecular aberrations in patients with myelodysplastic syndromes, and may become useful as a poor risk marker in these patients. These findings await validation in prospective trials.  相似文献   
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