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51.
Objective: Plaque accumulation on implant surfaces can result in peri-implantitis with potential implant loss. The aim of the present study was to examine the influence of zirconium nitride (ZrN) as a potential implant surface on the biofilm composition and diversity in vivo .
Material and methods: ZrN- or titanium (Ti)-coated glass specimens and ZrN or roughened Ti discs were used as substrates. Pure glass and polished titanium served as controls. The specimens were mounted on removable intraoral splints in five adults. After 24 h of intraoral exposure, the biofilms were analyzed applying single-strand conformation polymorphism (SSCP analysis) of 16S rRNA genes. Sequence analysis of the dominant bands excised from the SSCP fingerprints allowed to taxonomically describe bacteria derived from biofilm samples.
Results: The highest number of bands was counted on pure glass and Ti 800. ZrN-coated glass and ZrN-coated titanium discs showed the lowest values for species richness. However, no significant differences were observed regarding the diversity of the identified bacterial species among all the surfaces examined. A total of 46 different bacteria were identified. The dominant bands within the fingerprints indicated bacteria belonging to the Streptococcus group as identified by their 16S rDNA sequence.
Conclusion: A coating of glass surfaces with ZrN significantly reduced the species richness in early bacterial colonization but the diversity was not significantly changed. In consideration of the results obtained by this and former studies a ZrN coating appears to rather modify the quantity of early bacterial adherence than the quality of the microbial community structure.  相似文献   
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Tools are required to identify 'multi-endemic' population segments – in order to benefit the most vulnerable people and to make public health interventions cost-effective. The article suggests a comprehensive risk assessment and surveillance system approach based on a combination of epidemiological, environmental and social determinants. Such a cross-disciplinary approach will combine the advantages of forecasting upcoming disease 'hot spots' with provision of evidence for long-term planning under more stable conditions, and it may in principle apply to any combination of public health problems depending on the local context.  相似文献   
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Aim: The aim of this study was to assess the prevalence and extent of periodontal diseases among adults in a province in Eastern Germany.
Material and Methods: The Study of Health in Pomerania is a population-based study conducted during 1997–2001. The net random sample comprised 4310 20–81-year-old subjects. Periodontal status was assessed at four surfaces using a half-mouth recording protocol.
Results: The prevalence of attachment loss 3 mm was 89.7%, with 62.8% of teeth being affected. Probing depths 4 mm were prevalent in 69.7% of subjects, and 29.6% of teeth were affected. 25.3% of all subjects had severe pockets (6 mm). Periodontitis was significantly more prevalent in males. For attachment loss, the prevalence and extent increased significantly with increasing age, whereas probing depth values levelled off after the age of 40. In older subjects, increased recession and attachment loss were found, while the probing depth remained constant. According to the recent CDC classification, 17.6% and 33.3% of persons had severe and moderate periodontitis, respectively. The prevalence of periodontitis increased significantly with age and remained constant after the age of 50–59.
Conclusions: Periodontitis is more prevalent in Pomerania than in the United States or Western Europe. In older subjects, attachment loss steadily increased, while the probing depth remained constant.  相似文献   
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Systolic left ventricular function was examined by radionuclide ventriculography in 12 habitual smokers with known or suspected ischaemic heart disease, aged 33-69 years, before, during, and after smoking of two cigarettes in a row and was repeated on a non-smoking control day. Plasma concentrations of adrenaline, noradrenaline, renin, and angiotensin II were determined on the smoking day, before and immediately after smoking. During smoking, there were significant increases in heart rate (+27%), rate-pressure product (+23%), and cardiac output (+14%) in the face of a significant increase in left ventricular end-systolic volume (+5%) and significant decreases in ejection fraction (-6%) and stroke volume (-8%). Blood pressure was virtually unchanged, and total peripheral resistance remained constant. Plasma adrenaline increased by 100%, renin decreased by 21%, and noradrenaline and angiotensin II did not change. The humoral changes were not correlated to changes in any of the haemodynamic variables. Areas of myocardial hypokinesis emerged or widened during smoking in 11 of 12 patients. Thus, in patients with known or suspected ischaemic heart disease, smoking was associated with an acute decrease in systolic ventricular function and development of widespread hypokinesis despite adrenaline stimulation.  相似文献   
58.
Objectives. We assessed if prolonged-release melatonin can facilitate withdrawal of long-term benzodiazepine usage in patients with schizophrenia or bipolar disorder. Methods. Randomised, placebo-controlled, blinded, parallel superiority trial of 24 weeks duration. Participants were randomised to prolonged-release melatonin 2 mg daily versus matching placebo and were continuously guided to gradually reduce their usual benzodiazepine dosage. The primary outcome was mean benzodiazepine daily dosage at 24 weeks. Secondary outcomes included pattern of benzodiazepine dosage over time, benzodiazepine cessation proportion, and benzodiazepine withdrawal symptoms. Results. In total, 86 patients (21–74 years) were enrolled: 42 were randomised to melatonin versus 44 to placebo. We found no significant effect of melatonin on mean benzodiazepine dosage at 24 weeks (melatonin group 8.01 mg versus placebo group 5.72 mg diazepam equivalents; difference between means –2.29; 95% CI –5.78 to 1.21; P = 0.20). Benzodiazepine cessation proportion was 38.1% (16/42) in the melatonin group versus 47.7% (21/44) in the placebo group (OR 0.64; 95% CI 0.26 to 1.56; P = 0.32). Prolonged-release melatonin had no effect on benzodiazepine withdrawal symptoms. Conclusions. Benzodiazepine dosage was comparably low between the groups after 24 weeks of guided gradual dose reduction. In this context, prolonged-release melatonin did not seem to further facilitate benzodiazepine discontinuation.  相似文献   
59.

Background

Optimal surgical management of the buccal mucosa harvest site in patients with urethral stricture disease during buccal mucosa graft urethroplasty (BMGU) remains controversial.

Objective

To analyze in detail intensity and quality of pain as well as oral morbidity following closure (C) versus nonclosure (NC) of the donor site.

Design, setting, and participants

Randomized controlled trial on 135 patients treated with BMGU between October 15, 2014 and December 18, 2015.

Intervention

Following computer-based randomization, 63 and 72 patients, respectively, received C and NC of the donor site at the inner cheek. Preoperatively, on days 1, 5, and 21 as well as at 3 and 6 mo postoperatively, patients completed standardized questionnaires, including validated questions on intensity and quality of pain as well as oral morbidity.

Outcome measurements and statistical analysis

The coprimary end points were intensity and quality of oral pain. Secondary end points included oral morbidity and intensity of pain of the perineogenital region. Generalized linear mixed models evaluated the effect of various covariates on intensity and quality of oral pain, oral morbidity, as well as intensity of pain of the perineogenital region.

Results and limitations

There was noninferiority for NC versus C in intensity and affective quality of oral pain at every time point following BMGU. Oral morbidity and complications included pain, bleeding, swelling, numbness, alteration of salivation and taste, as well as impairment of mouth opening, smiling, whistling, diet, and speech. Time from BMGU had significant effects on intensity (p < 0.001) and quality of oral pain (sensory pain: p < 0.001, affective pain: p < 0.001, total pain: p < 0.001). Length of buccal mucosa graft had significant effects on intensity (p = 0.001) and quality of oral pain (sensory pain: p = 0.020, total pain: p = 0.042).

Conclusions

NC is noninferior to C of the donor site in intensity and quality of oral pain, and offers a treatment alternative. Time from BMGU and length of the buccal mucosa graft have effects on oral morbidity and complications.

Patient summary

We investigated pain, morbidity, and complications following closure (C) versus nonclosure (NC) of the buccal mucosa harvest site in patients undergoing buccal mucosa graft urethroplasty (BMGU). We found that NC is not worse than C regarding oral pain. In addition, time from BMGU and length of the buccal mucosa graft have effects on oral morbidity and complications.  相似文献   
60.
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