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Eccrine syringofibroadenoma is a rare benign tumor of the skin arising from the acrosyringeal portion of the eccrine duct. The tumor was first described by Mascaro in 1963, and since then only 8 case reports in 6 publications have been documented. This lesion is likely to be misdiagnosed both clinically and histologically due both to its rarity and its similarity to other more aggressive skin tumors. This report of 2 cases is presented to highlight the salient pathologic and clinical features of the tumor and to describe the long term follow up of 2 patients in whom the lesions have been electively reviewed rather than excised.  相似文献   
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This study examined sociodemographic, behavioral and psychosocial factors associated with BMI, weight perceptions and trying to lose weight among African-American smokers (N=600, M=44.2 years, 70% female). Sixty-eight percent of the sample were overweight or obese (sample BMI M=28.0, SD=6.7). Three separate, simultaneous multivariable regression models were used to determine which factors were associated with BMI, weight perceptions and trying to lose weight. Poorer health, female gender and high-school education or higher were significantly associated with higher BMIs (p<0.05). Being female (OR=5.8, 95% CI=3.6-9.3) and having a higher BMI (OR=0.6, 95% CI=0.5-0.6) was associated with perception of overweight and smoking more cigarettes per day (OR=1.0, 95% CI=1.0-1.1), and perceiving oneself as overweight (OR=14.1, 95% CI=8.2-24.2) was associated with trying to lose weight. Participants somewhat underestimated their BMI in their weight perceptions. Those who perceived themselves as overweight were more likely to be trying to lose weight; therefore, increasing participant awareness of actual BMI status may lead to improved weight-control efforts in African-American smokers. Several expected associations with outcomes were not found, suggesting that BMI and weight constructs are not well-understood in this population.  相似文献   
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The human rotavirus isolate B37 has a characteristic "super-short" RNA electropherotype and has been shown to represent a new VP7 serotype (M. J. Albert, L. E. Unicomb, and R. F. Bishop, 1987, J. Clin. Microbiol. 25, 183-185). The VP7 gene was cloned, and its nucleotide and predicted amino acid sequences were compared to other published VP7 gene sequences. Consistent with the serological evidence, two major antigenic regions of the B37 VP7 (i.e., regions A and B) differ in sequence from those of other G serotypes. Unexpectedly, the C antigenic region shows close similarity to G3 rotaviruses, but we were unable to detect a serological relationship using serotype 3 monoclonal antibodies.  相似文献   
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ObjectiveTo explore the use of detrended fluctuation analysis (DFA) scaling exponent of the awake electroencephalogram (EEG) as a new alternative biomarker of neurobehavioural impairment and sleepiness in obstructive sleep apnea (OSA).MethodsEight patients with moderate–severe OSA and nine non-OSA controls underwent a 40-h extended wakefulness challenge with resting awake EEG, neurobehavioural performance (driving simulator and psychomotor vigilance task) and subjective sleepiness recorded every 2-h. The DFA scaling exponent and power spectra of the EEG were calculated at each time point and their correlation with sleepiness and performance were quantified.ResultsDFA scaling exponent and power spectra biomarkers significantly correlated with simultaneously tested performance and self-rated sleepiness across the testing period in OSA patients and controls. Baseline (8am) DFA scaling exponent but not power spectra were markers of impaired simulated driving after 24-h extended wakefulness in OSA (r = 0.738, p = 0.037). OSA patients had a higher scaling exponent and delta power during wakefulness than controls.ConclusionsThe DFA scaling exponent of the awake EEG performed as well as conventional power spectra as a marker of impaired performance and sleepiness resulting from sleep loss.SignificanceDFA may potentially identify patients at risk of neurobehavioural impairment and assess treatment effectiveness.  相似文献   
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We report 2 cases of bacteremia due to "Helicobacter rappini" in 2 young, homosexual men, including the first report of H. rappini in a human immunodeficiency virus-positive patient. Blood cultures showed a spiral, fusiform, gram-negative bacterium with bipolar sheathed flagella.  相似文献   
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ABSTRACT: BACKGROUND: Although current clinical practice guidelines recommend Motivational Interviewing for use with smokers not ready to quit, the strength of evidence for its use is rated as not optimal. The purpose of the present study is to address key methodological limitations of previous studies by ensuring fidelity in the delivery of the Motivational Interviewing intervention, using an attention-matched control condition, and focusing on unmotivated smokers whom meta-analyses have indicated may benefit most from Motivational Interviewing. It is hypothesized that MI will be more effective at inducing quit attempts and smoking cessation at 6-month follow-up than brief advice to quit and an intensity-matched health education condition. METHODS: A sample of adult community resident smokers (N= 255) who report low motivation and readiness to quit are being randomized using a 2:2:1 treatment allocation to Motivational Interviewing, Health Education, or Brief Advice. Over 6 months, participants in Motivational Interviewing and Health Education receive 4 individual counseling sessions and participants in Brief Advice receive one brief in-person individual session at baseline. Rigorous monitoring and independent verification of fidelity will assure the counseling approaches are distinct and delivered as planned. Participants complete surveys at baseline, week 12 and 6-month follow-up to assess demographics, smoking characteristics, and smoking outcomes. Participants who decide to quit are provided with a self-help guide to quitting, help with a quit plan, and free pharmacotherapy. The primary outcome is self-report of one or more quit attempts lasting at least 24 hours between randomization and 6-month follow-up. The secondary outcome is biochemically confirmed 7-day point prevalence cessation at 6-month follow-up. Hypothesized mediators of the presumed treatment effect on quit attempts are greater perceived autonomy support and autonomous motivation. Use of pharmacotherapy is a hypothesized mediator of Motivational Interviewing's effect on cessation. DISCUSSION: This trial will provide the most rigorous evaluation to date of Motivational Interviewing's efficacy for encouraging unmotivated smokers to make a quit attempt. It will provide also provide effect-size estimates of MI's impact on smoking cessation to inform future clinical trials and inform the clinical practice guidelines. Trial registration ClinicalTrials.gov NCT01188018.  相似文献   
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Deep Lake in Antarctica is a globally isolated, hypersaline system that remains liquid at temperatures down to −20 °C. By analyzing metagenome data and genomes of four isolates we assessed genome variation and patterns of gene exchange to learn how the lake community evolved. The lake is completely and uniformly dominated by haloarchaea, comprising a hierarchically structured, low-complexity community that differs greatly to temperate and tropical hypersaline environments. The four Deep Lake isolates represent distinct genera (∼85% 16S rRNA gene similarity and ∼73% genome average nucleotide identity) with genomic characteristics indicative of niche adaptation, and collectively account for ∼72% of the cellular community. Network analysis revealed a remarkable level of intergenera gene exchange, including the sharing of long contiguous regions (up to 35 kb) of high identity (∼100%). Although the genomes of closely related Halobacterium, Haloquadratum, and Haloarcula (>90% average nucleotide identity) shared regions of high identity between species or strains, the four Deep Lake isolates were the only distantly related haloarchaea to share long high-identity regions. Moreover, the Deep Lake high-identity regions did not match to any other hypersaline environment metagenome data. The most abundant species, tADL, appears to play a central role in the exchange of insertion sequences, but not the exchange of high-identity regions. The genomic characteristics of the four haloarchaea are consistent with a lake ecosystem that sustains a high level of intergenera gene exchange while selecting for ecotypes that maintain sympatric speciation. The peculiarities of this polar system restrict which species can grow and provide a tempo and mode for accentuating gene exchange.Deep Lake (DL) is an extremely cold and hypersaline environment that has the distinction of being the least productive lake ever recorded (13). The lake is a marine-derived system in the Vestfold Hills, East Antarctica, having been isolated from the Southern Ocean by isostatic rebound of the continent ∼3,500 y BP (2, 4, 5) (SI Appendix, Fig. S1). The temperature exceeds 0 °C only in the top few meters for a few summer months per year, and it remains ice-free even in winter when temperatures drop to −40 °C (air) and −20 °C (throughout the lake) (1, 6). Microbial diversity is extremely low, and is dominated by members of the haloarchaea (7). Within this ecosystem, the putative primary producer is the green alga Dunaliella sp., which is found at low biomass concentrations (810).From DL, Halorubrum lacusprofundi, the first member of the Archaea domain isolated from a cold environment (11), has been formally described (12). In the laboratory, H. lacusprofundi grows across a wide range of temperatures from −1 °C to 42 °C, with fastest growth rate occurring at ∼33 °C (12, 13). It is capable of using a number of different carbon sources including glucose, mannose, acetate and ethanol, providing it with a seemingly versatile heterotrophic metabolism (12). Aside from studies that have noted the ability of H. lacusprofundi, and a recent isolate, tADL (14), to form aggregates and biofilms at either high or low temperatures (13, 15, 16), the only studies addressing adaptive responses are those linking the production of unsaturated diether membrane lipids to cold adaptation in H. lacusprofundi (3, 17).Various mechanisms that alter genetic composition have been reported in haloarchaea, including archaeal viruses, conjugative plasmids, genome rearrangements mediated by transposons, and significant levels of gene exchange via the formation of heterodiploids followed by homologous recombination (1825). All these studies have been confined to temperate or tropical systems, not polar environments.For some bacteria, the relationship between recombination frequency and sequence divergence appears to be log-linear (26, 27) but may be as much as two orders of magnitude higher in haloarchaea, such as for Haloferax volcanii and Haloferax mediterranei, which readily undergo cell fusion and DNA exchange (25, 28). Forces driving speciation in microbes include niche adaptation, selective sweeps, genetic drift, recombination, and geographic isolation (29). However, it is unclear how these forces would maintain species homogeneity or bring about lineages when gene flow is high, as is the case in haloarchaea. Although selection is important for speciation, it has been argued that the rate of genomic recombination may be a key determinant when considering sympatric speciation. Modeling has shown that high recombination rates are necessary to generate a new species when an ecological trait inferring increased fitness is controlled by many adaptive loci (30). However, these same high levels of recombination may also increase the number of intermediate (suboptimal) genotypes and reduce “completeness” of speciation. The dynamics of this sympatric evolution hypothesis have not been examined in real populations.The DL system is geographically very isolated, its organismal growth rates are very low, and the combination of cold plus hypersalinity may be expected to promote the physical process of DNA transformation to levels that exceed those of warm hypersaline environments. In this context, we examined the genomes of four recent haloarchaeal isolates and metagenome data from DL to assess genome variation and patterns of gene exchange and derive an understanding of how this unique Antarctic lake community evolves.  相似文献   
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