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21.
Objective:To assess accuracy of and interobserver agreement on multiparametric MR findings to distinguish uterine leiomyoma (LM) from uterine leiomyosarcoma (LMS) and soft tissue tumour of unknown malignant potential.Methods:Inclusion criteria: All females over 18 years with least one uterine mass measuring 5 cm or more in at least one of the three standard orthogonal dimensions on MR with histopathological confirmation of LM, LMS, or soft tissue tumour of unknown malignant potential (STUMP) in the 3 months following MR. Patients with LMS were drawn from a larger cohort being assessed for MR-guided focussed ultrasound (MRgFUS) suitability. Image evaluation: Assessed variables were: lesion margin, margin definition, T2 signal homogeneity, >50% of lesion with T2 signal brighter than myometrium, haemorrhage, restricted diffusion, contrast enhancement (CE), CE pattern, local lymphadenopathy and ascites.Results:32 LM, 10 LMS and 1 STUMP were evaluated. Ill-defined (p-value = 0.0003–0.0004) or irregular (p = 0.003–0.004) lesion margin, T2 hyperintensity >50% (p = 0.001–0.004), and peripheral CE (p = 0.02–0.05) were significantly more common in LMS/STUMP than LM for both radiologists. 10/11 (Reader 2) and 11/11 (Reader 1) LMS/STUMP displayed restricted diffusion but so did 63–80% of LM. Agreement was greatest for margin characteristics (κ = 0.73–0.81).Conclusion:Irregular/ill-defined lesion margin best distinguished LMS/STUMP from LM with good interrater reliability.Advances in knowledge:Assessment of agreement regarding MR parameters distinguishing LM from LMS and STUMP has not previously been undertaken in a cohort including a large number of patients with LMS. This will help inform evaluation of females considering minimally invasive LM treatment.  相似文献   
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MDX‐1097 is an antibody specific for a unique B cell antigen called kappa myeloma antigen (KMA) that consists of cell membrane‐associated free kappa light chain (κFLC). KMA was detected on kappa human multiple myeloma cell lines (κHMCLs), on plasma cells (PCs) from kappa multiple myeloma (κMM) patients and on κPC dyscrasia tissue cryosections. In primary κMM samples, KMA was present on CD38+ cells that were CD138 and CD45 positive and/or negative. MDX‐1097 exhibited a higher affinity for KMA compared to κFLC and the latter did not abrogate binding to KMA. MDX‐1097‐mediated antibody‐dependent cellular cytotoxicity (ADCC) and in vitro exposure of target cells to the immunomodulatory drug lenalidomide resulted in increased KMA expression and ADCC. Also, in vitro exposure of peripheral blood mononuclear cells (PBMCs) to lenalidomide enhanced MDX‐1097‐mediated ADCC. PBMCs obtained from myeloma patients after lenalidomide therapy elicited significantly higher levels of MDX‐1097‐mediated ADCC than cells obtained prior to lenalidomide treatment. These data establish KMA as a relevant cell surface antigen on MM cells that can be targeted by MDX‐1097. The ADCC‐inducing capacity of MDX‐1097 and its potentiation by lenalidomide provide a powerful rationale for clinical evaluation of MDX‐1097 alone and in combination with lenalidomide.  相似文献   
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Objective

To estimate the frequency of acquired ADAMTS13 deficiency in severe cases of Hemiscorpius lepturus stung patients and the frequency of acute kidney injury (AKI) in these patients.

Methods

Sixty scorpion stung children who were referred with severe hemolysis and hemoglobinuria were studied. None of them had received blood products and no one had a past medical history of renal failure.

Results

Plasma levels of ADAMTS13 and ADAMTS13 antibody (IgG) were measured using ELISA. ADAMTS13 was decreased in 91.7 % of patients and the anti-ADAMTS13 antibody (Ab) was increased in 98.3 %. ADAMTS13 decreased in all of the patients with acute kidney injury and none of those with normal levels of ADAMTS13 developed renal failure; all patients with AKI had also increased levels of ADAMTS13Ab. Acute kidney injury was found in 23.3 % and had significant association with severe anemia, thrombocytopenia, pyuria, hematuria and considerable proteinuria (p?<?0.001). Disseminated intravascular coagulation (DIC) and Hemolytic uremic syndrome (HUS) developed in 6.7 % and 10 % respectively.

Conclusions

The index findings demonstrate that Hemiscorpius lepturus sting is usually associated with ADAMTS13 deficiency, and increased ADAMTS13 autoantibody. These combined mechanisms may contribute to scorpion sting-induced coagulopathies and may predispose patients to develop DIC and HUS.  相似文献   
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Yolk–shell nanoparticles (YSNPs) are a new class of hollow nanostructures, and their unique properties can be utilized in drug delivery systems. The recent progress in YSNPs-based carriers is highlighted in drug delivery systems. Doxorubicin hydrochloride, ceftriaxone sodium, and methotrexate are three of the most common drugs that are used in this field. According to the reported studies, the materials used most often as yolk–shells are magnetic nanoparticles and polymers. The used methods for synthesizing a diverse array of YSNPs are classified based on their core structures. Various properties of YSNPs include their high drug-loading capacity, and their ability to decrease drug toxicity and satisfactorily and efficiently release drugs.

The recent progress in yolk–shell nanoparticles (YSNPs) as a new class of hollow nanostructures applied for drug delivery.  相似文献   
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ObjectiveIncreasingly, medical journals are recognizing “equally credited authors” (ECA) in the primary and senior authorship of articles. The aim of this study was to assess the policies of co–first authorship, co–senior authorship, and designation of a corresponding author in the radiology literature.MethodsWe identified 29 radiology journals based on impact factor ranking. Journal offices were contacted by phone and e-mail to ascertain their practices on first and senior authorship ECA designations. We surveyed the March, June, and December 2018 issues of each journal (when available) to assess the utilization of the co-designations in articles.ResultsTwenty-five of 29 journals responded to our survey (response rate: 86.2%). Of 25 journals, 20 (80%) allowed co–first authorship. Among these, 4 of 25 journals (16%) allowed more than two co–first authors. Among the 25 responses, 14 journals (56%) allowed co–senior authorship. Among the 24 journals who responded to this specific question, 23 (96%) approved designation of a corresponding author, different from the first or senior author. The review of March, June, December 2018 editions found co–first authorship and co–senior authorship ECA rates of 8.6% (range 0.0%-22.7%) and 1.8% (range 0.0%-13.3%), respectively. A corresponding author other than first or senior author was noted in 13.3% (range 0.0%-34.7%).DiscussionThere has been widespread acceptance of the concept of ECA in the policies of the top cited imaging journals particularly for first authors (80%). However, the utilization of these designations is uncommon for first authorship (8.6%) and rare (1.8%) for senior authorship based on our 2018 sampling.  相似文献   
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Journal of Autism and Developmental Disorders - Although previous research has shown that the transition to adulthood may be challenging, there exists a lack of research regarding perspectives of...  相似文献   
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