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There is considerable interest in foregoing axillary dissection (AD) when the sentinel node (SN) is positive in early breast cancer, particularly when involvement is minimal (micrometastases or isolated tumor cells). To address this issue we analyzed outcomes in patients with a single micrometastatic SN who did not receive AD. We selected 377 consecutive patients treated at the European Institute of Oncology between 1999 and 2007 for invasive breast cancer. Classical and competing risks survival analyses were performed to estimate prognostic factors for axillary recurrence, first events and overall survival. Median age was 53?years (range 26?C80); median follow-up was 5?years (range 1?C9). Most (91.8%) patients received conservative surgery; 209 (55.4%) had only one SN (range 1?C8). Five-year overall survival was 97.3%. There were 10 local events, 2 simultaneous local and axillary events, 6 axillary recurrences and 12 distant events. The cumulative incidence of axillary recurrence was 1.6% (95% CI 0.7?C3.3). By multivariable analysis, tumor size and grade were significantly associated with axillary recurrence. The high five-year survival and low cumulative incidence of axillary recurrence in this cohort provide justification for the increasingly common practice of foregoing AD in women with minimal SN involvement, and suggest in particular that AD can safely be avoided in women with small, low-grade tumors. Nevertheless, a subset of patients might be at high risk of developing overt axillary disease and efforts should be made to identify such patients by ancillary analyses of the results of ongoing or recently published clinical trials.  相似文献   
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BACKGROUND:

Azacitidine induces responses and prolongs overall survival compared with conventional care regimens in patients who have high‐risk myelodysplastic syndromes (MDS). However, limited data are available concerning the efficacy and safety of azacitidine in patients who have lower risk MDS.

METHODS:

The authors retrospectively evaluated 74 patients with International Prognostic Scoring System low‐risk or intermediate 1‐risk MDS, who received azacitidine on a national named patient program. At baseline, 84% of patients were transfusion‐dependent, 57% had received erythropoietin, and 51% were aged >70 years. Azacitidine was administered subcutaneously for 5 days (n = 29 patients), 7 days (n = 43 patients), or 10 days (n = 2 patients) every month at a dose of 75 mg/m2 daily (n = 45 patients) or at a fixed dose of 100 mg daily (n = 29 patients) and for a median of 7 cycles (range, 1‐30 cycles).

RESULTS:

According to the 2006 International Working Group criteria, overall response rate (ORR) was 45.9%, including complete responses (10.8%), partial responses (9.5%), hematologic improvements (20.3%), and bone marrow complete responses (5.4%). The ORR was 51.6% in 64 patients who completed ≥4 cycles of treatment. The median duration of response was 6 months (range, 1‐30 months). After a median follow‐up of 15 months, 71% of patients remained alive. A survival benefit was observed in responders versus nonresponders (94% vs 54% of patients projected to be alive at 2.5 years, respectively; P < .0014). The most common grade 3 or 4 adverse events were myelosuppression (21.6%) and infection (6.8%).

CONCLUSIONS:

The current results indicated that azacitidine may be a feasible and effective treatment for patients with lower risk MDS. Cancer 2010. © 2010 American Cancer Society.  相似文献   
106.

Background

To retrospectively compare the diagnostic accuracy of magnetic resonance imaging (MRI) and multidetector-row computed tomography (MDCT) in the assessment of the mandibular invasion by squamous cell carcinoma (SCC) having histopathological exams as standard of reference.

Materials and methods

Institutional review board approval with a waiver of informed patient consent was obtained. Of the 147 patients selected from our database who underwent surgical excision of a tumour arising into the oral cavity, thirty-six patients (26 men, 10 women; mean age, 56 years; range, 30-75 years) with hystologically proven SCC who performed both a preoperative MRI and MDCT, composed our final study population.Images were qualitatively analyzed in consensus by two expert radiologist in head and neck imaging. Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were assessed for both MRI and MDCT.Differences in sensitivity, specificity, positive and negative predictive values were calculated at a statistical significance of p < .05.

Results

The sensitivity, the specificity and the accuracy of MRI and MDCT in the detection of the mandibular involvement were respectively 93%, 82%, 86% and 79%, 82%, 81%, while the positive predictive value (PPV) and negative predictive value (NPV) were respectively 76%, 95% and 73%, 86%. There wasn''t any statistically significant difference in overall diagnostic accuracy between MRI and MDCT in the evaluation of mandibular tumour invasion (p > .05).

Conclusion

MRI showed to have a higher sensitivity compare to MDCT in the assessment of mandibular involvement from SCC arising in the oral cavity although none statistically significant differences were noted.  相似文献   
107.
PurposeTo provide guidance for clinicians about the diagnosis, staging and treatment of breast cancer occurring during an otherwise uncomplicated pregnancy.MethodsAn international expert Panel convened to address a series of questions identified by a literature review and personal experience. Issues relating to the diagnosis and management of breast cancer after delivery were outside the scope.ResultsThere is a paucity of large and/or randomized studies. Based on cohort studies, case series and case reports, the recommendations represent the best available evidence, albeit of a lower grade than is optimal.RecommendationsIn most circumstances, serious consideration should be given to the option of treating breast cancer whilst continuing with the pregnancy. Each woman should ideally be referred to a centre with sufficient expertise, given a clear explanation of treatment options. Most diagnostic and staging examinations can be performed adequately and safely during pregnancy. Treatment should however be adapted to the clinical presentation and the trimester of the pregnancy: surgery can be performed during all trimesters of pregnancy; radiotherapy can be considered during the first and second trimester but should be postponed during the third trimester; and standard chemotherapies can be used during the second and third trimester. Since neonatal morbidity mainly appears to be related to prematurity, delivery should not be induced before 37 weeks, if at all possible.ConclusionsThe treatment of breast cancer in pregnancy should be executed by experienced specialists in a multidisciplinary setting and should adhere as closely as possible to standard protocols.  相似文献   
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109.
Antiviral microbicides, topical agents that prevent sexually transmitted infections, mainly work by blocking the interaction between viral proteins and cell surface components. In many instances, virus–cell interaction is mediated by cell surface heparan sulfate proteoglycans (HSPGs). HSPGs are exploited as attachment receptors by three sexually transmitted viruses: Human Immunodeficiency Virus (HIV), Herpes Simplex Virus (HSV) and Human Papilloma Virus (HPV). Since these viruses can either infect or co-infect humans, virus/HSPGs interaction is a preferential target for the development of wide-spectrum antiviral microbicides. Several polyanionic compounds prevent HIV, HSV and HPV infections in cell culture models by acting as heparan sulfate (HS)-antagonists. However, three promising polyanionic compounds recently failed to pass phase III clinical trials designed to establish their efficacy in preventing HIV acquisition. In this scenario, new polyanionic compounds must be added to the pipeline of candidate microbicides and their development as effective drugs reconsidered. The capsular K5 polysaccharide from Escherichia coli has the same structure as the heparin/HS biosynthetic precursor. Chemical and enzymatic modifications have led to the synthesis of K5 derivatives with different degrees of sulfation and charge distribution and devoid of anticoagulant activity and cell toxicity. Recently attracting attention as candidate microbicides, they potently inhibit a broad spectrum of HIV-1 strains and genital types of HPV and HSV-1 and 2 in vitro. With a focus on the K5 derivatives, this article reviews the literature on polyanions as antiviral microbicides and discusses the possible therapeutic implications of this novel class of compounds.  相似文献   
110.
Evidence has gathered that CD28 costimulation facilitates T cell activation by potentiating TCR intrinsic-signaling. However, the underlying molecular mechanism is largely unknown. Here we show that, by enhancing T cell/APC close contacts, CD28 facilitates TCR signal transduction. Moreover, the signal supplied by CD28 does not lead to increased Zap-70 and Lat phosphorylation, but amplifies PLCgamma1 activation and Ca(2+) response. We provide evidence that the PTK Itk controls the latter function. Our data suggest that CD28 binding to B7 contributes to setting the level of TCR-induced phosphorylated Lat for recruiting signaling complexes, whereas the CD28 signal boosts multiple pathways by facilitating PLCgamma1 activation. These results should provide a conceptual framework for understanding quantitative and qualitative aspects of CD28-mediated costimulation.  相似文献   
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