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91.

Introduction

A decreased frequency of unprotected sex during episodes of concurrent relationships may dramatically reduce the role of concurrency in accelerating the spread of HIV. Such a decrease could be the result of coital dilution – the reduction in per-partner coital frequency from additional partners – and/or increased condom use during concurrency. To study the effect of concurrency on the frequency of unprotected sex, we examined sexual behaviour data from three communities with high HIV prevalence around Cape Town, South Africa.

Methods

We conducted a cross-sectional survey from June 2011 to February 2012 using audio computer-assisted self-interviewing to reconstruct one-year sexual histories, with a focus on coital frequency and condom use. Participants were randomly sampled from a previous TB and HIV prevalence survey. Mixed effects logistic and Poisson regression models were fitted to data from 527 sexually active adults reporting on 1210 relationship episodes to evaluate the effect of concurrency status on consistent condom use and coital frequency.

Results

The median of the per-partner weekly average coital frequency was 2 (IQR: 1–3), and consistent condom use was reported for 36% of the relationship episodes. Neither per-partner coital frequency nor consistent condom use changed significantly during episodes of concurrency (aIRR=1.05; 95% confidence interval (CI): 0.99–1.24 and aOR=1.01; 95% CI: 0.38–2.68, respectively). Being male, coloured, having a tertiary education, and having a relationship between 2 weeks and 9 months were associated with higher coital frequencies. Being coloured, and having a relationship lasting for more than 9 months, was associated with inconsistent condom use.

Conclusions

We found no evidence for coital dilution or for increased condom use during concurrent relationship episodes in three communities around Cape Town with high HIV prevalence. Given the low levels of self-reported consistent condom use, our findings suggest that if the frequency of unprotected sex with each of the sexual partners is sustained during concurrent relationships, HIV-positive individuals with concurrent partners may disproportionately contribute to onward HIV transmission.  相似文献   
92.
Background: Destructive membranous periodontal disease, or ligneous gingivitis, is a rare condition involving nodular gingival enlargement with ulceration and periodontal tissue destruction. This review gives a brief account of the cases reported in the literature. An effort is also made to define the periodontal disease caused by plasminogen deficiency with a view to its potential inclusion in the classification of periodontal diseases. Methods: A MEDLINE/PubMed and manual search was conducted to find papers describing ≥1 case of ligneous disease involving the oral mucosa. Results: We identified 23 articles reporting 35 cases. For each patient, we analyzed various characteristics, including age, sex, age of onset, oral symptoms, histologic features, plasminogen levels (functional activity, plasma antigen), genetic features, treatment, and results of treatment during the reported follow‐up. Conclusions: Ligneous gingivitis is a rare periodontal disorder closely associated with ligneous conjunctivitis and plasminogen deficiency. Its diagnosis may be supported by the finding of genetic mutations responsible for the condition. Research is focusing on the future development of an effective therapy capable of arresting the destructive evolution of the disease. Additional studies, investigating features such as probing depth and attachment loss, are needed for the appropriate classification of this periodontal disease.  相似文献   
93.
Objective: To compare actual antibiotic use to the stratification based on the sepsis calculator in newborns with suspected early onset sepsis (EOS). To investigate differences in EOS risk and vital signs between newborns that received early (<12?h) versus late antibiotics (≥12?h of life).

Methods: Newborns born ≥34 weeks gestation in 2014 treated with antibiotics started within 72?h after birth were included. We calculated the risk per 1000 live births and retrospectively assigned each newborn to one of four recommended categories using the sepsis calculator.

Results: There were 2094 newborns, 111 (5.3%) received antibiotics and 108 newborns were included. The incidence of culture-proven EOS was 0.096%. In 57 newborns, the advice of the sepsis calculator was not to start antibiotic therapy. Antibiotic treatment was started early in 66 (61%) and late in 42 (39%) newborns. In the “late treatment” group, clinical condition deteriorated, including two newborns with culture-proven EOS. Tachypnea and respiratory distress were significantly more present.

Conclusion: Antibiotic use could be reduced by more than 50%. Newborns with initial low sepsis risk score clinically deteriorated beyond 12?h of life. Continuous good clinical observation remains very important. Prospective validation is necessary to evaluate the safety of this approach.  相似文献   
94.
Birth weight is the single most important risk indicator for neonatal and infant mortality and morbidity, which has led to the idiom that 'every ounce counts'. Birth weight in turn, however, tends to vary widely across populations as a result of differential fetal growth velocity with such demographic factors as ethnicity, maternal and paternal height and altitude of residence. Accordingly, it has been acknowledged that the appraisal of birth weight should rely on its position relative to the birth weight distribution of the background population. This is commonly done by standardizing birth weight through its deviation from the population mean in the given gestational age stratum, as can be obtained from population-customized birth weight nomograms. This issue was recently revisited in 'Human Reproduction' through a plea for reporting birth weight as z-scores. In this article, we argue that adjustment for factors, such as gestational age, which may lie on the causal pathway from exposures present at the time of conception [e.g. single-embryo transfer (SET) versus double-embryo transfer (DET)] to birth weight, may induce bias, regardless of whether the adjustment happens via stratification, regression or through the use of z-scores.  相似文献   
95.
96.
Treatment plan optimization is a multi-criteria process. Optimizing solely on one objective or on a sum of a priori weighted objectives may result in inferior treatment plans. Manually adjusting weights or constraints in a trial and error procedure is time consuming. In this paper we introduce a novel multi-criteria optimization approach to automatically optimize treatment constraints (dose-volume and maximum-dose). The algorithm tries to meet these constraints as well as possible, but in the case of conflicts it relaxes lower priority constraints so that higher priority constraints can be met. Afterwards, all constraints are tightened, starting with the highest priority constraints. Applied constraint priority lists can be used as class solutions for patients with similar tumour types. The presented algorithm does iteratively apply an underlying algorithm for beam profile optimization, based on a quadratic objective function with voxel-dependent importance factors. These voxel-dependent importance factors are automatically adjusted to reduce dose-volume and maximum-dose constraint violations.  相似文献   
97.
Diagnosis of adult-onset Still's disease: contribution of biology   总被引:1,自引:0,他引:1  
We report one case of adult-onset Still's disease. The diagnosis of this disease currently requires application of Yamaguchi's criteria and then exclusion of infectious, haematological, autoimmune and neoplasic disorders. The place of biology is enhanced with the use of new markers like ferritin and glycosylated ferritin. Low percentage of glycosylated ferritin (<20%) in presence of very high level of ferritin, unexplained prolonged fever with leukocytosis can help to diagnosis. However, glycosylated ferritin is not yet of in routine use.  相似文献   
98.
99.

Background

Informant discrepancies between mother and child have challenged the assessment, classification, and treatment of childhood anxiety. Despite numerous studies on this matter, the implications and consequences for research and clinical practice remain unclear.

Objective

The present study aimed to obtain meaningful clinical information about informant discrepancies by examining mother–child agreement for anxiety subtypes, and by exploring mother–child discrepancies in relation to independent observer ratings of behavioral anxiety.

Method

The screen for child anxiety related emotional disorders was administered to 79 mothers and clinically referred anxious children aged 7–13 years. Mother–child dyads were observed during an anxiety-provoking task and independent observers rated children’s observed anxiety.

Results

The findings indicated a high level of mother–child disagreement on reports of anxiety. There was variability in levels of agreement between subtypes of anxiety, with significantly stronger mother–child agreement for separation compared to other forms of anxiety. Observed proximity between the mother and child was positively associated with child-reported separation anxiety and children’s observed anxious voice was negatively associated with child-reported panic disorder.

Conclusions

The results highlight the need to incorporate a multi-informant assessment of childhood anxiety in clinical practice and research, in particular for subtypes of anxiety problems that are characterized by less observable and more internally experienced components.
  相似文献   
100.
PURPOSE: The purpose of this prospective randomized controlled clinical study was to evaluate the clinical performance of a "mild" two-step self-etching adhesive, Clearfil SE, in Class V restorations after 5 years of clinical functioning. MATERIALS AND METHODS: Twenty-nine patients received two or four restorations following two randomly assigned experimental protocols: (1) a mild self-etching adhesive (Clearfil SE, Kuraray) was applied following manufacturer's instructions on both enamel and dentin (C-SE non-etch); (2) similar application of Clearfil SE, but including prior selective acid-etching of the enamel cavity margins with 40% phosphoric acid (C-SE etch). Clearfil AP-X (Kuraray) was used as the restorative composite for all 100 restorations. The clinical effectiveness was recorded in terms of retention, marginal integrity, marginal discoloration, caries recurrence, postoperative sensitivity, and preservation of tooth vitality after 5 years of clinical service. The hypothesis tested was that selective acid etching of enamel with phosphoric acid improved retention, marginal integrity, and clinical microleakage of Class V restorations. RESULTS: Only one restoration of the C-SE non-etch group was lost at the 5-year recall. All other restorations were clinically acceptable. Marginal integrity deteriorated with time in both groups. The number of restorations with defect-free margins was significantly lower in the C-SE non-etch group (p = 0.0043). This latter group presented significantly more small incisal marginal defects on the enamel side (p = 0.0169). Superficial marginal discoloration increased in both groups, but was more pronounced in the C-SE non-etch group and was related to the higher frequency of small incisal marginal defects. CONCLUSION: The clinical effectiveness of the two-step self-etching adhesive Clearfil SE remained excellent after 5 years of clinical service. Additional etching of the enamel cavity margins resulted in an improved marginal adaptation on the enamel side; however, this was not critical for the overall clinical performance of the restorations.  相似文献   
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