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991.
F. PARAZZINI S. FRANCESCHI C. LA VECCHIA L. CHATENOUD & E. DI CINTIO 《International journal of gynecological cancer》1997,7(3):169-181
Endometrial, ovarian and cervical cancer are among the leading causes of death in women. The role of unopposed estrogens in endometrial carcinogenesis is well established. Any factor that increases the exposure of the endometrium to unopposed estrogen, such as menopausal replacement treatment, obesity, or irregular menstrual cycles tends to raise the risk of the disease, while factors that lower exposure to estrogens or increase progesterone levels, such as oral contraceptives (OC) or smoking, decrease the risk. These well-established risk factors can have different effects at different ages, particularly in pre- and postmenopausal women: more generally, the interaction between various factors is still not totally defined. With reference to ovarian cancer, OC and parity, late menopause and lifelong regular menstrual periods increase the risk of the disease. In terms of biologic mechanisms, these factors are thought to act on ovarian cancer risk by affecting lifetime number of ovulations. Along this line, 'incessant ovulation' could be the relevant exposure that defines the incidence of the neoplasm. Among the factors other than reproductive or hormonal, diet is likely to be the most relevant, but it is still. however, poorly quantified. There is now consistent evidence that Human Papillomavirus (HPV) has a causal role in the ethiology of cervical cancer and that sexual habits and reproductive/hormonal factors are associated with the risk of invasive cervical cancer. Less clear is the role of smoking and dietary habits, but recent studies have shown a direct relationship between smoking and the risk of invasive cervical cancer and an inverse one between selected vitamin intake and risk of the disease. In this paper we review and discuss these evidences. 相似文献
992.
Aromatic DNA adducts in foundry workers in relation to exposure, life style and CYP1A1 and glutathione transferase M1 genotype 总被引:3,自引:2,他引:3
Hemminki K; Dickey C; Karlsson S; Bell D; Hsu Y; Tsai WY; Mooney LA; Savela K; Perera FP 《Carcinogenesis》1997,18(2):345-350
Levels of aromatic DNA adducts in foundry workers and controls were
followed at four annual samplings. During this time exposure to polycyclic
aromatic hydrocarbons (PAH) decreased and the level of DNA adducts
decreased accordingly. In the total group exposure was related to the level
of adducts. Adduct levels correlated with urinary 1- hydroxypyrene
(LOGU1OH), air benzo[a]pyrene, weekly working hours and daily cigarette
consumption. In a multivariate model 1-hydroxypyrene had a consistent
effect. Neither glutathione transferase M1 (GSTM1) nor cytochrome P450 1A1
(CYP1A1) genotypes had clear effects. Yet the individuals lacking GSTM1 had
a stronger effect of LOGU1OH and some effect by other sources of PAH, such
as charcoal broiled food, although all these variables were not significant
in the multivariate model. The rare individuals with a CYP1A1 polymorphism
MspI containing an amino acid change at isoleucine had an increased level
of adducts. The results showed that the postlabelling method used was able
to detect an increase in aromatic DNA adducts in leukocytes when exposure
to benzo[a]pyrene in air was approximately 5 ng/m3. At such low levels
smoking and charcoal broiled food may be important contributors to adducts.
相似文献
993.
妊娠肝内胆汁淤积症患者脂质过氧化作用的变化与雌激素水平及受体的关系 总被引:9,自引:0,他引:9
目的 探讨妊娠肝内胆汁淤积症 (intrahepatic cholestasis of pregnancy,ICP)患者血清丙二醛 (MDA)和超氧化物岐化酶 (SOD)含量的变化与游离雌三醇 (E3 )和胎盘雌激素受体 (ER)水平之间的关系。 方法 取 ICP患者 33例为研究组 ,另选同期入院的正常产妇 30例作为对照组 ,两组均在分娩前 30 min内取肘静脉血 3ml,测定 MDA、SOD、E3 及 β- h CG。随机选择 ICP组和正常对照组2 0例测定胎盘组织中 ER和 HCG水平。 结果 ICP组中 MDA为 (6 .4± 2 .1) m ol/L、E3 为 (19± 9)ng/m l高于对照组 (5 .2± 1.4) m ol/L,14± 6 ) ng/ml(P<0 .0 1)。 SOD、β- h CG与对照组相比无显著差异 (P>0 .0 5 )。ICP组中胎盘组织 ER的阳性表达百分比 70 %高于对照组 2 5 % (P<0 .0 5 ) ,而 HCG的阳性百分比在两组间无显著差异 (P>0 .0 5 )。 ICP组 E3 与胎盘 ER水平之间有正相关关系 r=0 .6 3。而 β- h CG与胎盘 HCG水平则无显著相关 (P>0 .0 5 )。 结论 妊娠期 ICP患者体内氧化和抗氧化失衡及雌激素水平升高与胎盘 ER表达增强 ,对 ICP的发生可能起重要的作用 相似文献
994.
Pubertal linear growth of Indian girls adopted in Sweden 总被引:1,自引:0,他引:1
LA Proos J. Karlberg Y. Hofvander T. Tuvemo 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(8):641-644
Pubertal linear growth in 66 adopted Indian girls was studied. The infancy-childhood-puberty standard was used, since it is applicable to Indian girls, and enables determination of the onset and height gain of the pubertal growth phase in an individual. At arrival in Sweden, mean height was —2.8 SDS. Despite rapid catch-up growth, the girls were still below the reference mean (—0.8 SDS) at the onset of the pubertal growth spurt, which occurred approximately 1.5 years earlier than in Swedish girls and also earlier than in Indian girls. The pubertal height gain, however, was equivalent to that in Swedish girls with similar timing of puberty. The short final height found in some of these girls appears to be related to shortness prior to puberty and to very early onset of an otherwise normal pubertal growth component. 相似文献
995.
F Jalil BS Lindblad LA Hanson SR Khan RN Ashraf B Carlsson S Zaman J Karlberg 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S391):3-16
In this paper, details are given of a community based follow up study of four areas: a village, a periurban slum, an urban slum and an upper middle class control group living in and around Lahore, Pakistan. The aim was to characterize the determinants of child health in a rapidly urbanizing community. The study was undertaken in two steps. An initial cross-sectional survey collecting socio-economic and demographic background information was carried out between March to August 1984. This was followed by a longitudinal study of 1476 infants representing the outcome of the pregnancies registered continuously between September 1984 to March 1987 among the 3242 families in the study. These infants were followed monthly from birth to 3 years of age and thereafter less frequently. In this communication we describe the study design, the study population, the organization and the research methodology used, including the reasons for drop outs from birth to 24 months of age. The internal consistency of the data is also presented. After the initial examination of the newborns within between 0–7 days of birth, the infants were visited monthly for 24 months making a total of 20911 examinations. At 24 months of age 70% of the infants were still in the study, 11% had died before reaching this age, 13% had moved from the area and 6% had refused to participate in the study. The economic, conditions, social structure, and the quality of life were found, not surprisingly, to vary significantly among the four areas. This community-based project provides new, critical and reliable information for local health planners. The study highlights the importance of the development of a useful model for research collaboration between institutions in developed and developing countries. 相似文献
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