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81.
82.
Naqvi GA  Shafqat A  Awan N 《Injury》2012,43(6):838-842
BackgroundAnkle syndesmotic injuries are complex and require anatomic reduction and fixation. Tightrope fixation is a relatively new technique and we present the largest series of syndesmosis fixation using Arthrex Tightrope? (Naples, FL, USA).Materials and methodsForty-nine patients with ankle diastasis, treated with Arthrex tightrope?, were reviewed retrospectively, using American Orthopaedic Foot and Ankle Society (AOFAS) and Foot and Ankle Disability Index (FADI) scores and radiographic parameters for syndesmosis integrity. The operative technique was slightly modified by the senior author in 31 cases to avoid soft-tissue complications requiring removal of the implant. The aim of this study was to assess the rate of hardware removal after tightrope fixation and the effect of the author's modification to avoid soft-tissue complications.ResultsThe mean age of patients was 37.7 years. Eighteen were performed with standard technique whilst 31 with the modified technique. The mean radiological follow-up was 6 months. Final data were collected using a confidential questionnaire and FADI score at an average of 24 (12–38) months postoperatively. The average time to full weight bearing was 7.7 weeks and to return to normal activities was 11.2 weeks. Postoperative radiographic measurements demonstrated satisfactory reduction of syndesmosis. The Mean AOFAS score was 85.57(95% confidence interval (CI) 77.96–93.18) and the mean FADI score was 81.20 (95% CI 73.86–88.53). There were three cases of hardware removal in the standard technique group as compared to none in the group with the modified technique.ConclusionArthrex Tightrope? provides an effective method of syndesmosis stabilisation, which obviates the need for routine removal of implant and facilitates dynamic stabilisation. The results of this study are satisfactory and comparable to previously reported studies. We emphasise that surgeons must be aware of the potential risk of soft-tissue complications and recommend our modified technique. Further long-term prospective studies should be carried out to resolve this issue.  相似文献   
83.
During the last few decades major advances have shed light on nanotechnology. Nanomaterials have been widely used in various fields such as medicine, energy, cosmetics, electronics, biotechnology and pharmaceuticals. Owing to their unique physicochemical characteristics and nanoscale structures, nanoparticles (NPs) have the capacity to enter into plant cells and interact with intracellular organelles and various metabolites. The effects of NPs on plant growth, development, physiology and biochemistry have been reported, but their impact on plant specialized metabolism (aka as secondary metabolism) still remains obscure. In reaction to environmental stress and elicitors, a common response in plants results in the production or activation of different types of specialized metabolites (e.g., alkaloids, terpenoids, phenolics and flavonoids). These plant specialized metabolites (SMs) are important for plant adaptation to an adverse environment, but also a huge number of them are biologically active and used in various commercially-valued products (pharmacy, cosmetic, agriculture, food/feed). Due to their wide array of applications, SMs have attracted much attention to explore and develop new strategies to enhance their production in plants. In this context, NPs emerged as a novel class of effective elicitors to enhance the production of various plant SMs. In recent years, many reports have been published regarding the elicitation of SMs by different types of NPs. However, in order to achieve an enhanced and sustainable production of these SMs, in-depth studies are required to figure out the most suitable NP in terms of type, size and/or effective concentration, along with a more complete understanding about their uptake, translocation, internalization and elicitation mechanisms. Herein, we are presenting a comprehensive and critical account of the plant SMs elicitation capacities of the three main classes of nanomaterials (i.e., metallic NPs (MNPs), metal oxide NPs (MONPs) and carbon related nanomaterials). Their different proposed uptake, translocation and internalization pathways as well as elicitation mechanism along with their possible deleterious effect on plant SMs and/or phytotoxic effects are summarized. We also identified and critically discussed the current research gaps existing in this field and requiring future investigation to further improve the use of these nanomaterials for an efficient production of plant SMs.

Advancement in nanomaterials as novel elicitors of plant''s specialized secondary metabolites.  相似文献   
84.

Introduction

A high-fat diet and male obesity are aspects associated with germinal epithelial alterations and male infertility. Some reports have shown that certain tetracyclines can protect the germinal epithelium from toxic drugs. The aim of the present study design was to evaluate the possible effect of doxycycline on testicular germ cells in individuals fed a Western diet (atherogenic), using a murine model.

Methods

Two groups of male mice (BALB/c) were fed a high-fat Western diet (HFD). One of these two groups was given doxycycline at a dose of 10 mg/kg/day (HFD+Dox). A third group was fed a standard rodent diet (SD group). After 6 months, the mice were euthanized and morphologic and histopathologic analyses were performed.

Results

Germinal epithelial height was similar between the SD group (54 μm) and the HFD+Dox group (53 μm) (p = 0.26), and it was significantly reduced in the HFD group (47 μm) (p = 0.0001). The degree of germinal epithelial loss (DGEL) was significantly lower in the SD (10) and HFD+Dox (12.5) groups than in the HFD group (30) (p = 0.0001 and =0.007, respectively). There were no differences in the DGEL between the SD and HFD+Dox groups (p = 0.42).

Conclusions

Doxycycline administration was shown to prevent germinal epithelial loss in the testes of mice fed a high-fat diet. Future studies are necessary to evaluate the clinical usefulness of doxycycline or its analogs in persons with a habitual high-fat diet.  相似文献   
85.
The “ears of the lynx” sign was previously reported as a neuroimaging finding observed in patients with autosomal recessive hereditary spastic paraplegia in association with a thin corpus callosum (ARHSP–TCC). We report a patient with a chronic form of Marchiafava–Bignami disease (MBD) that presented with this imaging feature. Diffusion tensor imaging (DTI) and fiber‐tracking data support that this finding is a consequence of the structural derangement, which enlarges a preexisting border zone of the bundles of fibers from the corpus callosum (CC) genu to the forceps minor and anterior corona radiata. Therefore, we assume that despite their pathological differences, damage to the anterior portion of the CC is responsible for the imaging similarities between MBD and ARHSP–TCC.  相似文献   
86.
87.
Considering the severity of the HIV-1 subtype C epidemic, data on the epidemiology and distribution of HIV subtypes in India are relatively sparse. Keeping this in view, 28 env gene sequences from patients were sequenced and analyzed. The samples were collected over a period of 10 years from 1995 to 2004. Assessment of the interisolate genetic distances of the study isolates, which were all subtype C, showed interisolate distances varying from 2 to 19% (mean: 14%) with the maximum diversity observed in the samples collected in 2003-2004. Analysis of the phylogenetic relationships among subtype C env sequences from six different countries and our study isolates revealed an overall star-like phylogeny with almost all sequences from India forming a monophyletic lineage. A lower diversity within the immunodominant epitopes was found. The data generated from this study should prove valuable for the production of vaccine against subtype C.  相似文献   
88.
89.
Achalasia cardia is a disease of adolescents and is rare in children. In total, 12 children with primary achalasia, with a mean age of 10.8 +/- 2 years, were prospectively evaluated for the efficacy of a 30-mm-diameter Rigiflex balloon for relief of symptoms and weight gain after 1 and 6 months of follow up. The 12 children were evaluated and treated for achalasia, with pneumatic balloon dilatation, from January 1998 to December 2000. They were studied for basal, 1-, and 6-month post-dilatation composite symptoms for dysphagia, regurgitation, night cough and heartburn. Basal and 5-min post-dilatation barium swallow were obtained to compare barium height and width for efficacy of dilatation and to evaluate for complications. There were no complications. Barium height, width, composite symptom score and weight improved significantly up to the 6-month follow up. Rigiflex balloon dilatation of 30-mm diameter is safe and effective in children with achalasia.  相似文献   
90.
The wheat gene-rich region (GRR) 5L0.5 contains many important genes, including Ph1, the principal regulator of chromosome pairing. Comparative marker analysis identified 32 genes for the GRR controlling important agronomic traits. Detailed characterization of this region was accomplished by first physically localizing 213 wheat group 5L-specific markers, using group 5 nulli-tetrasomics, three Ph1 gene deletion/insertion mutants, and nine terminal deletion lines with their breakpoints around the 5L0.5 region. The Ph1 gene was localized to a much smaller region within the GRR (Ph1 gene region). Of the 61 markers that mapped in the four subregions of the GRR, 9 mapped in the Ph1 gene region. High stringency sequence comparison (e < 1 x10(-25)) of 157 group 5L-specific wheat ESTs identified orthologs for 80% sequences in rice and 71% in Arabidopsis. Rice orthologs were present on all rice chromosomes, although most (34%) were on rice chromosome 9 (R9). No single collinear region was identified in Arabidopsis even for a smaller region, such as the Ph1 gene region. Seven of the nine Ph1 gene region markers mapped within a 450-kb region on R9 with the same gene order. Detailed domain/motif analysis of the 91 putative genes present in the 450-kb region identified 26 candidates for the Ph1 gene, including genes involved in chromatin reorganization, microtubule attachment, acetyltransferases, methyltransferases, DNA binding, and meiosis/anther specific proteins. Five of these genes shared common domains/motifs with the meiosis specific genes Zip1, Scp1, Cor1, RAD50, RAD51, and RAD57. Wheat and Arabidopsis homologs for these rice genes were identified.  相似文献   
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