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421.
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Hepatozoon spp. are the most frequent intracellular protozoa in snakes. Considering the variety of parasites infecting specimens of Caudisona durissa terrifica and the divergent data in literature where only two species, Hepatozoon romani and Hepatozoon capsulata, are described, the aim of this study was to morphologically, morphometrically, and molecularly characterize Hepatozoon spp. from some naturally infected specimens of C. durissa terrifica, and observe changes caused by these protozoa in parasitized erythrocytes. Four snakes were examined. Two of them had two morphological distinct gamonts, while the other two had only one type of gamont. The six distinct gamonts were provisionally named gamonts A, B, C, D, E, and F. Statistical analysis, however, confirmed the existence of only four parasite populations, those which were capable of inducing significant alterations in determined red blood cells variables. Attempts to infect Aedes aegypti and Culex quinquefasciatus mosquitoes were done for each snake specimen. Some mosquitoes became infected and oocysts were recovered and measured. The detection of Hepatozoon DNA was obtained with success but the molecular characterization was unable to differentiate species of the samples, with respect to the fragment studied.  相似文献   
423.
BackgroundWith the potential emergence of disease specific therapies, an accurate biomarker of Alzheimer’s Disease pathology is needed in cases in which the underlying etiology is uncertain. We explored the potential value of amyloid imaging in patients with atypical presentations of dementia.MethodsTwenty-eight patients with atypical dementia underwent positron emission tomography imaging with the amyloid imaging tracer Pittsburgh compound B (PiB). Twenty-six had [18F]fluoro-2-deoxy-D-glucose positron emission tomography scans. After extensive clinical evaluation, this group of patients generated considerable diagnostic uncertainty and received working diagnoses that included possible Alzheimer’s disease (AD), focal dementias (e.g., posterior cortical atrophy [PCA]), or cases in which no clear diagnostic category could be determined (dementia of uncertain etiology). Patients were classified as PiB-positive, PiB-negative, or PiB-intermediate, based on objective criteria. Anterior–posterior and left–right indices of PiB and [18F]fluoro-2-deoxy-D-glucose uptake were calculated to examine differences in distribution of amyloid pathology and metabolic changes associated with clinical phenotype.ResultsEleven patients (39%) were PiB positive, 16 were PiB negative (57%), and one (4%) was PiB intermediate. By diagnostic category, three of 10 patients (30%) with dementia of uncertain etiology, one of five (20%) with primary progressive aphasia, three of five (60%) with PCA, and four of seven (57%) with possible AD were PiB positive. Brain metabolism of both PiB-positive and PiB-negative patients was generally similar by phenotype, but appeared to differ from typical AD. PCA patients also appeared to differ in their relative distribution of PiB compared with typical AD, consistent with their atypical phenotype.ConclusionsAD pathology is frequently present in atypical presentations of dementia and can be identified by amyloid imaging. Clinical phenotype is more related to the pattern of cerebral hypometabolism than the presence/absence of amyloid pathology. These findings have diagnostic, prognostic, and therapeutic implications.  相似文献   
424.
IntroductionThe Ross procedure is an alternative to standard aortic valve (AV) replacement in young and middle-aged patients. However, durability and incidence of reoperation remain a concern for most cardiac surgeons. Our aim was to assess very long-term clinical and echocardiographic outcomes of the Ross procedure.MethodsWe conducted a single-center retrospective analysis of 56 consecutive adult patients who underwent the Ross procedure. Mean age at surgery was 44±12 years (range, 16-65 years) and 55% were male. Clinical endpoints included overall mortality and the need for valve reoperation due to graft failure. The echocardiographic endpoint was the presence of any graft deterioration. Median clinical follow-up was 20 years (1120 patient/years).ResultsIndications for surgery were dominant aortic stenosis in 50% and isolated aortic regurgitation in 21%. Concomitant mitral valve repair was performed in 21% and a subcoronary technique was most commonly used (86%). Overall long-term survival was 91%, 80% and 77% at 15, 20 and 24 years, respectively. The survival rate was similar to the age- and gender-matched general population (p=0.44). During the follow-up period, freedom from graft reoperation was 80%. Eleven patients (31%) developed moderate AV regurgitation, three (8.6%) developed moderate pulmonary regurgitation and one (2.9%) presented moderate pulmonary stenosis.ConclusionThe Ross procedure, mostly using a subcoronary approach, proved to have good clinical and hemodynamic results, with low reoperation rates in long-term follow-up. Moderate autograft regurgitation was a frequent finding but had no significant clinical impact.  相似文献   
425.
426.
目的:研究短期手法针刺足三里治疗对脂多糖诱导的实验性大鼠急性肺损伤的预防作用。 方法:根据是否进行脂多糖刺激及采用的针刺方法的不同,将32只Wistar大鼠随机分为4组,即正常对照组、模型组、假针刺组和针刺组,每组8只。假针刺组和针刺组大鼠行手法针刺治疗,连续治疗4 d,每次5 min。第4天针刺后采用脂多糖刺激诱导大鼠急性肺损伤。第5天,收集外周血、支气管肺泡灌洗液和骨髓等进行白细胞计数。 结果:血细胞计数和支气管肺泡灌洗液细胞计数提示,针刺可减轻急性肺损伤大鼠的炎性反应,假针刺也有轻微的效果。正常对照组和模型组大鼠无明显的炎性反应。与正常对照组比较,模型组肺泡灌洗液中细胞计数增加;与假针刺组比较,针刺组肺泡灌选液中细胞计数减少,但差异没有统计学意义。 结论:预防性手法针刺足三里可减轻脂多糖诱导的大鼠急性肺损伤,但其相关免疫机制仍待进一步的研究。  相似文献   
427.
Chronic lung infection is the major cause of morbidity and premature mortality in cystic fibrosis (CF) patients. Bacteria of the Burkholderia cepacia complex are the most threatening pathogens in CF, and a better understanding of how these bacteria adapt to the CF airway environment and resist the host defense mechanisms and therapeutically administered antibiotics is crucial. To provide clues to the adaptive strategies adopted by Burkholderia cenocepacia during long-term colonization, we carried out a phenotypic assessment of 11 clonal variants obtained at the major Portuguese CF Center in Lisbon from sputa of the same CF patient during 3.5 years of colonization of the lungs, until the patient's death with cepacia syndrome. Phenotypic characterization included susceptibility assays against different classes of antimicrobials and characterization of cell motility, cell hydrophobicity and zeta potential, colony and cell morphology, fatty acid composition, growth under iron limitation/load conditions, exopolysaccharide production, and size of the biofilms formed. The results suggest the occurrence of clonal expansion during long-term colonization. For a number of the characteristics tested, no isolation time-dependent consistent alteration pattern could be identified. However, the values for antimicrobial susceptibility and swarming motility for the first B. cenocepacia isolate, thought to have initiated the infection, were consistently above those for the clonal variants obtained during the course of infection, and the opposite was found for the zeta potential. The adaptive strategy for long-term colonization, described here for the first time, involved the alteration of membrane fatty acid composition, in particular a reduction of the degree of fatty acid saturation, in the B. cenocepacia variants retrieved, along with the deterioration of pulmonary function and severe oxygen limitation.  相似文献   
428.
Cyprinid herpesvirus-3 (CyHV-3), or koi herpesvirus (KHV), is responsible for high mortalities in aquaculture of both common carp (Cyprinus carpio carpio) and koi carp (Cyprinus carpio koi) worldwide. The complete genomes of three CyHV-3 isolates showed more than 99% of DNA sequence identity, with the majority of differences located in short tandem repeats, also called VNTR (variable number of tandem repeats). By targeting these variations, eight loci were selected for genotyping CyHV-3 by multiple locus VNTR analysis (MLVA). CyHV-3 strains obtained after sequential in vivo infections exhibited identical MLVA profiles, whereas samples originating from a single isolate passaged 6 and 82 times in vitro exhibited mutations in two of the eight loci, suggesting a relatively slow genetic evolution rate of the VNTRs. The method was subsequently applied on 38 samples collected in Indonesia, France and the Netherlands. Globally, the isolates grouped in two main genetic clusters, each one divided in two subgroups including either CyHV-3-U/I or CyHV3-J. Interestingly, Indonesian strains were rather distant from CyHV-3-J isolate. The results of the present study indicate that these VNTR molecular markers are efficient in estimating the genetic diversity among CyHV-3 isolates and are therefore suitable for further molecular epidemiological studies.  相似文献   
429.
The cleavage of amyloid precursor protein (APP) by caspases unmasks a domain extending from membrane to caspase cleavage site. This domain induces apoptosis in vitro and in vivo when overexpressed in neurons through the help of an internalization vector. In this model, we previously showed that SET rapidly binds to the internalized domain and is involved in downstream deleterious effects. Under these conditions SET mislocalizes from the nucleus to the cytoplasm, as in Alzheimer's disease (AD). In this report using the same model, we show that PAT1 attaches to the internalized domain earlier than SET and that this binding causes an increase in the levels of APP and APLP2 at the cell surface. Down regulation experiments of PAT1 and of APP and APLP2 show that the increase of the levels of APP and APLP2 at the cell surface triggers the cell death signal and SET mislocalization into the cytoplasm. In the context of AD these data suggest that mislocalization of SET into the cytoplasm may occur downstream of first cell death signal events involving PAT1 protein.  相似文献   
430.
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