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61.
BackgroundEvidence for face-mask wearing in the community to protect against respiratory disease is unclear.AimTo assess effectiveness of wearing face masks in the community to prevent respiratory disease, and recommend improvements to this evidence base.MethodsWe systematically searched Scopus, Embase and MEDLINE for studies evaluating respiratory disease incidence after face-mask wearing (or not). Narrative synthesis and random-effects meta-analysis of attack rates for primary and secondary prevention were performed, subgrouped by design, setting, face barrier type, and who wore the mask. Preferred outcome was influenza-like illness. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) quality assessment was undertaken and evidence base deficits described.Results33 studies (12 randomised control trials (RCTs)) were included. Mask wearing reduced primary infection by 6% (odds ratio (OR): 0.94; 95% CI: 0.75–1.19 for RCTs) to 61% (OR: 0.85; 95% CI: 0.32–2.27; OR: 0.39; 95% CI: 0.18–0.84 and OR: 0.61; 95% CI: 0.45–0.85 for cohort, case–control and cross-sectional studies respectively). RCTs suggested lowest secondary attack rates when both well and ill household members wore masks (OR: 0.81; 95% CI: 0.48–1.37). While RCTs might underestimate effects due to poor compliance and controls wearing masks, observational studies likely overestimate effects, as mask wearing might be associated with other risk-averse behaviours. GRADE was low or very low quality.ConclusionWearing face masks may reduce primary respiratory infection risk, probably by 6–15%. It is important to balance evidence from RCTs and observational studies when their conclusions widely differ and both are at risk of significant bias. COVID-19-specific studies are required.  相似文献   
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The mammalian intestine is home to a dense community of bacteria and its associated bacteriophage (phage). Virtually nothing is known about how phages impact the establishment and maintenance of resident bacterial communities in the intestine. Here, we examine the phages harbored by Enterococcus faecalis, a commensal of the human intestine. We show that E. faecalis strain V583 produces a composite phage (ϕV1/7) derived from two distinct chromosomally encoded prophage elements. One prophage, prophage 1 (ϕV1), encodes the structural genes necessary for phage particle production. Another prophage, prophage 7 (ϕV7), is required for phage infection of susceptible host bacteria. Production of ϕV1/7 is controlled, in part, by nutrient availability, because ϕV1/7 particle numbers are elevated by free amino acids in culture and during growth in the mouse intestine. ϕV1/7 confers an advantage to E. faecalis V583 during competition with other E. faecalis strains in vitro and in vivo. Thus, we propose that E. faecalis V583 uses phage particles to establish and maintain dominance of its intestinal niche in the presence of closely related competing strains. Our findings indicate that bacteriophages can impact the dynamics of bacterial colonization in the mammalian intestinal ecosystem.  相似文献   
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Study Objective1) To quantify the incidence and severity of postdischarge nausea and vomiting (PDNV) for 7 days in adults undergoing outpatient surgeries with general anesthesia; 2) to evaluate whether a risk model previously developed for the first two postoperative days may be used to predict the patient’s risk of PDNV for 7 days; and 3) to verify whether the same risk factors are applicable in the 3 to 7 day period.DesignProspective study.SettingTwo university-affiliated centers.Patients248 adult (> 18 years) surgical outpatients undergoing ambulatory surgical procedures with general anesthesia between 2007 and 2008.MeasurementsThe incidence and severity of PDNV and a simplified risk score for PDNV was assessed prospectively from discharge up to 7 postoperative days.Main ResultsThe overall incidence of nausea was 56.9% and of emesis was 19.4%. The incidence of PDNV was highest on the day of surgery (DOS), with PDNV of 44.8% and decreasing over time to 6.0% on day 7. Using the simplified risk score for PDNV the area under the receiver operating characteristic (ROC) curve was 0.766 (0.707, 0.825). A previous history of postoperative nausea and vomiting (PONV; OR 3.51, CI 1.70 - 7.27), operating room time (odds ratio [OR] 2.19, 95% CI 1.34 - 3.60), use of ondansetron in the Postanesthesia Care Unit (PACU; OR 6.39, CI 1.65-24.79), and pain during days 3–7 (OR 1.67, CI 1.30 - 2.14) were the strongest predictors of PDNV on days 3–7.ConclusionsPDNV affects a significant number of patients after ambulatory surgery, and our simplified PDNV score may be applied to a 7-day population. Pain appears to be a factor in late PDNV. It is possible that the presence of PDNV during days 3–7 has different origins from the PDNV that resolved over the first 48 hours.  相似文献   
68.

Background

Cardiovascular disease is the leading cause of increased mortality for adolescents with advanced kidney disease. The quality of preventive cardiovascular care may impact long-term outcomes for these patients.

Methods

We reviewed the records of 196 consecutive adolescents from eight centers with pre-dialysis chronic kidney disease, on dialysis or with a kidney transplant, who transferred to adult-focused providers. We compared cardiovascular risk assessment and therapy within and across centers. Predictors of care were assessed using multilevel models.

Results

Overall, 58 % (range 44–86 %; p?=?0.08 for variance) of five recommended cardiovascular risk assessments were documented. Recommended therapy for six modifiable cardiovascular risk factors was documented 57 % (26–76 %; p?=?0.09) of the time. Of these patients, 30 % (n?=?59) were reported to go through formal transition which was independently associated with a 21 % increase in composite cardiovascular risk assessment (p?<?0.001). Transfer after 2006 and kidney transplant status were also associated with increased cardiovascular risk assessment (p?<?0.01 and p?=?0.045, respectively).

Conclusions

Adolescents with kidney disease receive suboptimal preventive cardiovascular care, that may contribute to their high risk of future cardiovascular mortality. A great opportunity exists to improve outcomes for children with kidney disease by improving the reliability of preventive care that may include formal transition programs.  相似文献   
69.

Objectives

To determine if brushing dentine with 2 moderate RDA desensitising toothpastes, results in a significant dentine wear difference and whether this difference continues to be relevant when preceded with an erosive challenge.

Methods

An in situ, single centre, single blind, randomised, split mouth study, evaluated the difference in abrasion of 2 toothpastes (SFM - Sensodyne Fresh Mint® RDA 70; CPHM - Crest Pro-Health Clean Mint® RDA 120) in 28 healthy volunteers. Two toothpaste treatments were administered 3×/day, for each of the two 15 day periods, subjects wearing bi-lateral, lower buccal appliances each with 4 dentine sections. A 2 min extra-oral acidic challenge preceded toothbrushing for 2 study arms. Contact profilometry measured samples at baseline, days 5, 10 and 15.

Results

Brushing with SFM was significantly less abrasive than brushing with CPHM at all time points, with or without a preceding acidic challenge (p < 0.0001). The additional dentine loss arising from the erosive challenge prior to brushing with each paste was linear with time and independent of abrasive effect.

Conclusions

The desensiting toothpastes’ RDA, directly related to dentine loss with toothbrushing. An acidic challenge prior to brushing did not negate the benefits of reduced wear from the lower RDA paste compared to the higher RDA paste. When brushing eroded dentine, the additional wear appeared independent of abrasive effect. Dentine hypersensitivity sufferers should be recommended to use a low-moderate RDA toothpaste, not to brush more than 2×/day and not immediately following an acidic challenge.  相似文献   
70.
Background: Brief procedures that reduce smoking behaviour may be useful in reaching the many people that do not seek help for smoking addiction.

Objectives: The current study aimed to determine if one component of Acceptance and Commitment Therapy (ACT), cognitive defusion, could be useful in reducing smoking behaviour in a sample of students.

Methods: The study employed a between-subjects three-arm design. For one week, participants were asked to reduce their cigarette consumption. To aid them in their reduction, participants were randomly allocated to one of three conditions: the first received a defusion procedure, the second received an experiential avoidance procedure and a control condition received no procedure. For a second week, the instruction to reduce cigarette consumption was lifted. During both weeks participants were required to monitor their smoking behaviour via a tally diary system.

Results: The defusion condition smoked significantly less than the control condition during week one and significantly less than the control and experiential avoidance conditions during week two.

Conclusion: Results are discussed in terms of the potential utility of defusion in this domain, and the limitations of this preliminary research that would need to be addressed in future investigations.  相似文献   

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