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排序方式: 共有5137条查询结果,搜索用时 31 毫秒
991.
Bültmann U Rugulies R Lund T Christensen KB Labriola M Burr H 《Social psychiatry and psychiatric epidemiology》2006,41(11):875-880
Background The aim of this paper is to examine the impact of depressive symptoms on long-term sickness absence in a representative sample
of the Danish workforce.
Methods This prospective study is based on 4,747 male and female employees, participating in the Danish Work Environment Cohort Study.
Depressive symptoms were measured at baseline. Data on sickness absence were obtained from a national register on social transfer
payments. Onset of long-term sickness absence was followed up for 78 weeks.
Results The cumulative 78 weeks incidence for the onset of long-term sickness absence was 6.5% in men and 8.9% in women. Both men
and women with severe depressive symptoms (≤52 points) were at increased risk of long-term sickness absence during follow-up
(men: HR = 2.69; 95% CI: 1.18, 6.12; women: HR = 2.27; 95% CI: 1.25, 4.11), after adjustment for demographic, health related,
and lifestyle factors. When we divided the depressive symptom scores into quartiles, we found no significant effects with
regard to long-term sickness absence.
Conclusions Severe depressive symptoms, as measured with the MHI-5, increased the risk of future long-term sickness absence in the general
Danish working population. However, effects were not linear, but occurred mostly only in those employees with high levels
of depressive symptoms. 相似文献
992.
Arne Nørby Rasmussen Poul Aabo Osterhammel Søren Peter Lund Gitte Bondegård Kristiansen Svend Andersen 《International journal of audiology》2013,52(4):237-243
The aim of this work has been to construct and evaluate a system for recording distortion product otoacoustic emissions in rats at ultrasonic frequencies up to at least 50 kHz. The paper primarily describes the design of the acoustic probe system, as this is the most critical part. An acoustic ear simulator was developed and used for the subsequent calibration of the stimulus signals. A detachable probe system was provided in order to allow for visual inspection of the probe fitting in the ear canal prior to the final placement of the acoustic probe.Test/retest performance was evaluated by comparing DP-grams and I/O curves in 12 anaesthetized Wistar rats in two sessions separated approximately by one week. The between subject variance of the 12 tested rats appeared to be very modest, thus making the setup suitable for testing, for instance, ototoxicity of drugs or detection of cochlear damage due to noise exposures in rodents. 相似文献
993.
Tine Rubak Samuel Kock Birger Koefoed-Nielsen Søren Peter Lund Jens Peter Bonde 《International journal of audiology》2013,52(3):109-114
The purpose was to investigate the relationship between noise exposure and tinnitus among workers with normal hearing and hearing loss, respectively. We conducted a cross-sectional survey of 752 workers employed at 91 workplaces, that were investigated by means of full work-shift noise levels, questionnaire data, and bilateral pure-tone audiometry. Tinnitus was not associated with the present noise level, the duration of noise exposure, or the cumulative noise exposure if participants had normal hearing. As expected, such trends were demonstrated if participants had a hearing handicap. Based on these data, we will be cautious in ascribing tinnitus to noise exposure in our patients’ workplaces if they have a normal audiogram. Furthermore our data indicates no risk of noise-induced tinnitus at exposure levels where no hearing loss would be expected, e.g. as usually encountered in non-industrial workplaces. 相似文献
994.
Anne Vested Cecilia H?st Ramlau-Hansen Sjurdur Frodi Olsen Jens Peter Bonde Susanne Lund Kristensen Thorhallur Ingi Halldorsson Georg Becher Line Sm?stuen Haug Emil Hagen Ernst Gunnar Toft 《Environmental health perspectives》2013,121(4):453-458
Background: Perfluorinated alkyl acids (PFAAs), persistent chemicals with unique water-, dirt-, and oil-repellent properties, are suspected of having endocrine-disrupting activity. The PFAA compounds perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are found globally in humans; because they readily cross the placental barrier, in utero exposure may be a cause for concern.Objectives: We investigated whether in utero exposure to PFOA and PFOS affects semen quality, testicular volume, and reproductive hormone levels.Methods: We recruited 169 male offspring (19–21 years of age) from a pregnancy cohort established in Aarhus, Denmark, in 1988–1989, corresponding to 37.6% of the eligible sons. Each man provided a semen sample and a blood sample. Semen samples were analyzed for sperm concentration, total sperm count, motility, and morphology, and blood samples were used to measure reproductive hormones. As a proxy for in utero exposure, PFOA and PFOS were measured in maternal blood samples from pregnancy week 30.Results: Multivariable linear regression analysis suggested that in utero exposure to PFOA was associated with lower adjusted sperm concentration (ptrend = 0.01) and total sperm count (ptrend = 0.001) and with higher adjusted levels of luteinizing hormone (ptrend = 0.03) and follicle-stimulating hormone (ptrend = 0.01). PFOS did not appear to be associated with any of the outcomes assessed, before or after adjustment.Conclusions: The results suggest that in utero exposure to PFOA may affect adult human male semen quality and reproductive hormone levels. 相似文献
995.
996.
Nynke R. Koning Frederike L. Büchner Marjolein E.A. Verbiest Robert R.J.M. Vermeiren Mattijs E. Numans Mathilde R. Crone 《The European journal of general practice》2013,19(3):116-127
Background: Although common and often with long-lasting effects, child mental health problems (MHPs) are still under-recognized and under-treated. A better understanding of the factors associated with the identification of MHPs in primary care may improve the recognition of MHPs.Objectives: To review studies on factors associated with the identification of child MHPs in primary care.Methods: Six leading databases were systematically searched until 1 October 2018. Two independent researchers selected articles and extracted data on study characteristics and factors associated with MHP identification. Inclusion criteria were the investigation of factors associated with MHP identification by primary care professionals (PCPs) in children aged 0–18 years.Results: Of the 6215 articles identified, 26 were included. Prevalence rates of PCP-identified MHPs varied between 7 and 30%. PCPs identified 26–60% of children with an increased risk of MHPs as indicated by MHP assessment tools, but associated factors were investigated in relatively few studies. MHPs were more often identified in children with a family composition other than married parents, with worse mental health symptoms, prior MHPs, among boys in elementary school, when contact with PCPs was related to parental psychosocial concerns or routine health check-ups, when PCPs were recently trained in MHPs or when PCPs felt less burdened treating MHPs.Conclusion: MHP identification varied substantially between studies and PCPs and was related to several child, family and practice factors. Future studies should systematically investigate factors associated with MHP identification by PCPs and specifically in children with an increased risk of MHPs according to mental health assessment tools. 相似文献
997.
998.
The effect of sectioning the trigeminal sensory root on the periodontally-induced jaw-opening reflex
The experiment was designed to determine the pathway taken to the brain stem by periodontal afferents responsible for the digastric jaw-opening reflex induced by tooth-tapping. Cutting the trigeminal sensory roots of anesthetized decerebrate cats eliminated the ipsilateral periodontally-induced reflex, although the stretch reflexes of the jaw-closing muscles were undiminished. These results suggest that periodontal afferents causing the jaw-opening reflex reach the brainstem through the Vth sensory root, and confirm that muscle spindle afferents travel through the Vth motor root. 相似文献
999.
In vitro solubility of human pulp tissue in calcium hydroxide and sodium hypochlorite. 总被引:1,自引:0,他引:1
The tissue solvent capacity of a 2% stabilized sodium hypochlorite solution (Milton) and a commercial calcium hydroxide solution (Calasept) was examined under in vitro conditions where autolyzed human pulp fragments weighing approximately 0.0065 g were immersed in these solutions at 37 degrees C for periods of up to 10 days. It appeared that sodium hypochlorite was able to dissolve half the volume of pulp tissue within 1 h and the remaining tissue after 2-2 1/2 h. Calcium hydroxide dissolved half the pulp volume within 2 h, whereas it took 1 week for the remaining tissue to dissolve. These findings support the use of sodium hypochlorite as an irrigation solution during canal preparation and calcium hydroxide as a canal dressing for the purpose of creating a canal free of pulp remnants before root filling. 相似文献
1000.