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The aim of this study is to develop a technical quality evaluation system of electroencephalogram (EEG) recording in order to acquire technically satisfactory EEG records, which may contribute to the accuracy improvement of EEG interpretation. In our developed system, the evaluation of EEG recording comprises the detection of technical artifacts and physiological status, which indicates the recording status objectively. In addition, the caution signals to users are generated in the system according to the undesired status detected. The information displayed to users includes the updated EEG records and instant evaluation results. Two examples of evaluation results are introduced in this paper, illustrating unsatisfactory records and artifact free records, respectively. The experimental results are proposed to verify the effectiveness of the technical quality evaluation of EEG recording. The implementation of the technical quality evaluation of EEG recording is helpful to acquire technically satisfactory EEG records, which may improve the accuracy of results in both the visual and the automatic EEG interpretation, and ease the laborious work of EEG technicians in the recording progress.  相似文献   
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BACKGROUND: Once food elimination is introduced, it is important to know for doctors when patients generally develop oral tolerance against eliminated food. To clarify the point, following study was conducted. METHODS: We analyzed 304 patient profiles with food allergy in our division between 1994 and 2001. The diagnosis of oral tolerance was determined by the results of food challenges or the accidental episodes of ingestion. RESULTS: By the age of 3 years old, 78% of food allergy patients with soybean, 63% of those with wheat, 60% of those with cow's milk, 51% of those with egg yolk, and 31% of those with egg white developed oral tolerance, respectively. IgE CAP RAST scores against cow's milk, egg yolk, and egg white in the patients without tolerance were significantly higher than those in the patients with tolerance. CONCLUSION: Patients developed oral tolerance firstly against soybean followed by wheat, cow's milk, egg yolk and egg white during the first 3 years of life. The specific IgE antibody levels against egg and cow's milk are important for the diagnosis of tolerance.  相似文献   
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OBJECTIVE: We investigated the usefulness of skin prick test (SPT) for the diagnosis of egg white (EW) allergy in infants with atopic dermatitis who showed negative to EW CAPRAST, and followed up the EW-CAPRAST in this study. SUBJECTS AND METHODS: Data of negative SPT using Bifurcated needle (BN) were analyzed from the data of 202 atopic dermatitis infants, who had received SPT from January in 2001 to April in 2005. From the negative SPT value (average and standard deviation) positive SPT value was obtained. Among 202 cases, 89 suspected-egg allergy infants with negative IgE CAPRAST against EW at the time of first visit were recruited to examine the usefulness of SPT. Positive conversion of EW-CAPRAST was checked in 78 cases (65: egg allergy+, 13: egg allergy(-)) who had been followed up in our outpatient clinic. RESULTS: Range of negative SPT control value (mean+2SD) using BF among infants could be set as less than 2 mm for wheal and/or 5 mm for erythema. Among 89 suspected-egg allergy infants with negative EW-CAPRAST, 72 infants (80.9%) were diagnosed as egg allergy by the combination of elimination and provocation test, interestingly 39 infants (54.2%) showed positive SPT results. In the follow up study of 78 negative EW-CAPRAST cases, 47 EW-CAPRAST out of 65 egg-allergy cases turned positive later infantile period (mean EW-CAPRAST: 9.6+/-16.7 Ua/ml at 9.9+/-5.6 months old). EW-CAPRAST of 7 cases in 13 non-egg allergies also turned positive in the follow up, however EW-CAPRAST titer was relatively lower compared to that of egg allergies (1.1+/-1.5 Ua/ml at 13.3+/-2.6 months old). CONCLUSIONS: We experienced fairly number of atopic infants with negative EW-CAPRAST at the first outpatient visit, who were later diagnosed as egg allergy. In about half of these cases, SPT egg-allergy infants, three quarter of EW-CAPRAST turned positive around 10 months old. EW-CAPRAST of atopic infants without egg allergy also turned transiently and slightly positive. In the conclusions, SPT seemed to be more useful than EW-CAPRAST for the diagnosis of egg allergy in early infantile period, however provocation test should be required for the definitive diagnosis in suspected-egg allergy infants without any proof of egg-sensitization.  相似文献   
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Genetic variation of influenza neuraminidase (NA), unlike for hemagglutinin (HA), has not been fully characterized. Therefore, we determined the relation between mutations in the NA and HA genome segments of 205 influenza A/H3N2 viruses isolated from patients in Japan during the five seasons from 2010 to 2015. The amino acid (AA) sequences of the NA and HA proteins in these isolates were then determined. In the 2011–2012 season, there was the emergence of isolates with NA and HA sequences containing AA93G (NA93G) and AA278K (HA278K), respectively (24/48 isolates, 50.0%). This was in contrast to NA93D-HA278N being detected exclusively in the previous 2010–2011 season (24/24 isolates, 100.0%). The isolates with the NA93G-HA278K substitutions became predominant in the following 2012–2013 season (95.8%, 46/48 isolates). The NA and HA phylogenetic trees of the 2011–2012 and 2012–2013 seasons were segregated by clades with NA93D-HA278N or NA93G-HA278K. In the subsequent 2013–2014 and 2014–2015 seasons, the strong relationship between NA93D-HA278N and NA93G-HA278K observed in the previous seasons, was no longer present and NA93G-HA278N (33/52 isolates, 63.5% in the 2014–2015 season) became predominant. In addition, the clades within the NA and HA trees could no longer be segregated based on NA AA93 and HA AA278. These findings suggest that the co-mutation of NA and HA AA sequences is present and may contribute to the formation of an epidemic lineage.  相似文献   
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To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) in the viruses epidemic in the 2016–17 Japanese influenza season, we measured the 50% inhibitory concentration (IC50) of these NAIs for influenza virus isolates from patients and compared them with the results from the 2010–11 to 2015–16 seasons.Viral isolation was done with specimens obtained prior to treatment, and the type and subtype was determined by RT-PCR using type- and subtype-specific primers. The IC50 was determined by a neuraminidase inhibition assay using a fluorescent substrate.A total of 276 virus isolates, 6 A (H1N1)pdm09 (2.2%), 249 A (H3N2) (90.2%), and 21 B (7.6%), had the IC50 measured for the four NAIs. B isolates included 11 (52.4%), 9 (42.9%), and one (4.8%) of the Victoria, Yamagata, and undetermined strains, respectively.No A (H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2016–17 season. No isolate with highly reduced sensitivity to the four NAIs have been found for A (H3N2) or B from the 2010–11 to 2016–17 seasons. No significant trend of increase or decrease was found in the geometric mean IC50s of the four NAIs during the seven studied seasons.These results indicate that the sensitivity to the four commonly used NAIs has been maintained and that any change in the effectiveness of these NAIs would be minute. Common usage of NAIs for patient treatment has not been a driving force in the selection of NAI resistant viruses.  相似文献   
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Narrow-band imaging optical chromocolonoscopy: Advantages and limitations   总被引:2,自引:0,他引:2  
Narrow-band imaging (NBI) is an innovative optical technology that modifies the center wavelength and bandwidth of an endoscope's light into narrow-band illumination of 415 :1: 30 nm. NBI markedly improves capillary pattern contrast and is an in vivo method for visualizing microvessel morphological changes in superficial neoplastic lesions. The scientific basis for NBI is that short wavelength light falls within the hemoglobin absorption band, thereby facilitating clearer visualization of vascular structures. Several studies have reported advantages and limitations of NBI colonoscopy in the colorectum. One difficulty in evaluating results, however, has been nonstandardization of NBI systems (Sequential and nonsequential). Utilization of NBI technology has been increasing worldwide, but accurate pit pattern analysis and sufficient skill in magnifying colonoscopy are basic fundamentals required for proficiency in NBI diagnosis of colorectal lesions. Modern optical technology without proper image interpretation wastes resources, confuses untrained endoscopists and delays interinstitutional validation studies. Training in the principles of "optical image-enhanced endoscopy" is needed to close the gap between technological advancements and their clinical usefulness. Currently available evidence indicates that NBI constitutes an effective and reliable alternative to chromocolonoscopy for in vivo visualization of vascular structures, but further study assessing reproducibility and effectiveness in the colorectum is ongoing at various medical centers.  相似文献   
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