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71.
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73.
Tatiana Aminoff Juhani Smolander Olli Korhonen Veikko Louhevaara 《European journal of applied physiology》1996,73(1-2):180-185
Ten young (aged 23–30 years) and nine older (aged 54–59 years) healthy men with similar estimated limb muscle volumes performed, in random order, three different types of ergometer exercise tests (one-arm cranking, two-arm cranking, and two-leg cycling) up to the maximal level. Values for work load (WL), peak oxygen consumption
, peak heart rate (HR), peak ventilation
, respiratory gas exchange ratio (R), recovery blood lactate concentration [La–], and rating of perceived exertion (RPE) were compared between the age-groups in the given exercise modes. No significant age-related differences in WL, peak
, peak HR, R, [La–], or RPE were found in one-arm or two-arm cranking. During one-arm cranking the mean peak
was 1.65 (SD 0.26)1 · min–1 among the young men and 1.63 (SD 0.10)1 · min–1 among the older men. Corresponding mean peak
during two-arm cranking was 2.19 (SD 0.32)1 · min-1 and 2.09 (SD 0.18)1 · min–1, respectively. During one-arm cranking peak
was higher (P < 0.05) among the older men compared to the young men. During two-leg cycling the young men showed higher values in WL (P < 0.001), peak
(P < 0.001), and peak HR (P < 0.001). The mean peak
was 3.54 (SD 0.24)1 · min–1 among the young men and 3.02 (SD 0.20)1 · min–1 among the older men. Corresponding mean peak HR was 182 (SD 5) beats · min–1 and 170 (SD 8) beats · min–1, respectively. During two-leg cycling, peak
, R, [La–], and RPE did not differ between the two age-groups. In summary, the older men with similar sizes of estimated arm and leg muscle volumes as the young men had a reduced physical work capacity in two-leg cycling. In one-arm or two-arm cranking, no significant difference in work capacity was found between the age-groups. These results indicate, that in healthy men, age, at least up to the 6th decade of life, is not necessarily associated with a decline in physical work capacity in exercises using relatively small muscle groups, in which the limiting factors are more peripheral than central. 相似文献
74.
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M Elovainio M Hurme M Jokela L Pulkki-Råback M Kivimäki M Hintsanen T Hintsa T Lehtimäki J Viikari OT Raitakari L Keltikangas-Järvinen 《Psychosomatic medicine》2012,74(7):675-681
Objective To examine whether the activation of indoleamine 2,3-dioxygenase (IDO), an enzyme involved in serotonin production, is associated with depressive symptoms. Methods The participants were 544 women and 442 men (aged 24-39 years) from the population-based Young Finns Study who participated in a medical examination in 2001 (including IDO and depression) and 2007 (follow-up assessment for depression). Results At baseline, IDO was associated with depressive symptoms (in the total cohort: B = 0.23, p < .001; women: B = 0.20, p = .007; men: B = 0.29, p = .002; p for interaction = .19). IDO at baseline was also associated with depressive symptoms at follow-up in women (B = 0.17, p = .03), which remained significant when adjusting for any of the biologic and behavioral risk factors. Adjusting for body mass index attenuated the association by 6%. In the final model including all baseline variables, none of the risk factors (except for baseline depressive symptoms) were associated with depressive symptoms at follow-up. Conclusions These data suggest that IDO activity may be a risk factor for future depression especially in women. IDO-induced alterations in serotonergic function may offer one biologic explanation to the well-established associations between inflammation and depression. 相似文献
76.
Hintsanen M Elovainio M Puttonen S Kivimaki M Koskinen T Raitakari OT Keltikangas-Jarvinen L 《International journal of behavioral medicine》2007,14(4):202-212
Background: Work stress indicated by effort—reward imbalance is hypothesized to cause autonomic arousal, which, if prolonged or frequent, could contribute to cardiovascular pathology. However, only limited empirical evidence on this mechanism is available. Purpose: This study examined associations between effort-reward imbalance, heart rate (HR), and heart rate variability (HRV). Method: The participants were 457 women and 406 men (mean age 32.3 years) derived from the population-based Young Finns Study. Effort—reward imbalance was defined as the ratio between effort and reward, higher efforts compared to rewards indicating greater imbalance. Results: In age-adjusted regression models, higher effort-reward imbalance was associated with lower HRV, and lower reward was associated with higher HR among women. These associations were not attenuated after additional adjustments for demographic characteristics and coronary risk factors. No significant associations of effort—reward imbalance or its components with HR and HRV were found in men. Conclusion: Our finding of lower HRV and higher HR in young healthy women with high effort—reward imbalance and low rewards provides evidence of a potential mechanism that may link effort-reward imbalance to the development of coronary heart disease (CHD) in women. 相似文献
77.
Puttonen S Elovainio M Kivimäki M Koskinen T Pulkki-Råback L Viikari JS Raitakari OT Keltikangas-Järvinen L 《Biological psychology》2008,78(2):204-210
Temperament, as indicated by Cloninger's psychobiological model predicts coronary heart disease risk, but its association with autonomic cardiac regulation, a potential mediating mechanism, is unclear. We examined the associations between temperament traits and autonomic cardiac regulation in a resting situation in 798 women and 580 men derived from a population-based sample. After adjustment for age and sex, harm avoidance was associated with lower level of high-frequency (HF) variation, root mean square successive differences (RMSSDs), the percentage of successive R–R intervals >50 ms (pNN50) and higher heart rate (HR) (all p ≤ 0.005), suggesting that harm avoidance is related to low parasympathetic activity. Additional adjustments for behavioral factors attenuated these associations more than the adjustment for biological risk factors. Novelty seeking was associated with higher RMSSD (p = 0.007) and pNN50 (p = 0.012) and lower heart rate (p < 0.001). With adjustment for behavioral risk factors, the associations with RMSSD (p = 0.136) and pNN50 (p = 0.236) attenuated to the null, but adjustment for biological risk factors had little effect. Reward dependence and persistence were unrelated to indices of cardiac regulation. 相似文献
78.
Anna Serlachius Marko Elovainio Markus Juonala Steven Shea Matthew Sabin Terho Lehtimäki Olli Raitakari Liisa Keltikangas-Järvinen Laura Pulkki-Råback 《International journal of behavioral medicine》2017,24(2):161-170
Purpose
The psychosocial determinants of prediabetes are poorly understood. The aims of our study were (1) to analyse the association between perceived social support in young adulthood and fasting glucose levels and prediabetes in mid-adulthood in a cohort of healthy Finns, (2) to explore whether body mass index (BMI), inflammation or depression mediate this relationship, (3) and to examine the association between social support trajectory groups and fasting glucose.Method
A prospective design was used with an analytic sample of 1250 participants aged 3–18 years at baseline (1980) and aged 12–39 years when social support was measured. Fasting glucose and prediabetes were assessed 32 years after baseline. Linear and logistic regression was used to examine the association between social support and the outcome measures. A bootstrapping technique was used to examine mediation effects.Results
Social support was associated with future glucose levels in women after adjusting for childhood socioeconomic status (SES) and youth depression (β = ?0.136, p = 0.001) and also predicted prediabetes in women after adjusting for childhood SES (β = 1.31, 95 % CI 1.02 to 1.69, p = 0.031). Both associations were attenuated after adjusting for BMI in mid-adulthood. BMI was found to mediate the relationship between social support and prediabetes in women (β for indirect effect β = 0.09, SE = 0.03, CI = 0.03 to 0.16).Conclusion
Low perceived social support in young adulthood is associated with high fasting glucose and prediabetes in mid-adulthood in women but not men. The association between social support and prediabetes in women can be partly explained by BMI.79.
Vainio P Gupta S Ketola K Mirtti T Mpindi JP Kohonen P Fey V Perälä M Smit F Verhaegh G Schalken J Alanen KA Kallioniemi O Iljin K 《The American journal of pathology》2011,178(2):525-536
The arachidonic acid and prostaglandin pathway has been implicated in prostate carcinogenesis, but comprehensive studies of the individual members in this key pathway are lacking. Here, we first conducted a systematic bioinformatic study of the expression of 36 arachidonic acid pathway genes across 9783 human tissue samples. The results showed that the PLA2G7, HPGD, EPHX2, and CYP4F8 genes are highly expressed in prostate cancer. Functional studies using RNA interference in prostate cancer cells indicated that all four genes are also essential for cell growth and survival. Clinical validation confirmed high PLA2G7 expression, especially in ERG oncogene-positive prostate cancers, and its silencing sensitized ERG-positive prostate cancer cells to oxidative stress. HPGD was highly expressed in androgen receptor (AR)-overexpressing advanced tumors, as well as in metastatic prostate cancers. EPHX2 mRNA correlated with AR in primary prostate cancers, and its inhibition in vitro reduced AR signaling and potentiated the effect of antiandrogen flutamide in cultured prostate cancer cells. In summary, we identified four novel putative therapeutic targets with biomarker potential for different subtypes of prostate cancer. In addition, our results indicate that inhibition of these enzymes may be particularly powerful when combined with other treatments, such as androgen deprivation or induction of oxidative stress. 相似文献
80.
Olli Nummela Tommi Sulander Antti Karisto Antti Uutela 《International journal of behavioral medicine》2009,16(2):189-194