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41.
In a group of 55 women with chronic pain due to pelvic congestion measurement by ultrasound revealed they had a larger uterus and thicker endometrium as compared with a group of normal women matched for age, parity and the presence of polycystic ovaries found on ultrasound scanning. Many women with pelvic congestion (56%) were found on ultrasound to have cystic changes in their ovaries which ranged from a classic polycystic pattern to the appearance of clusters of 4-6 cysts in bilaterally enlarged ovaries. It is suggested that uterine enlargement and thickening of the endometrium are caused by oestrogen, either from the effects on the target organs of an increased concentration or of hypersensitivity to oestrogen.  相似文献   
42.
Development and behaviour at five years were assessed in children from a national cohort; comparisons were drawn between those living in one-parent families, in step-parent families and with both natural parents. On average, children from one-parent families scored worst and children from two-parent families best on tests of behaviour, vocabulary and visuomotor co-ordination. The differences remained significant after allowing for associated influences. The behaviour of children from one-parent families and step-parent families was perceived on average as more 'anti-social' than that of children from two-parent families. Children in one-parent families were seen on average as marginally more 'neurotic' than children in two-parent families.  相似文献   
43.
TEENAGE MOTHERING: CHILD DEVELOPMENT AT FIVE YEARS   总被引:1,自引:0,他引:1  
Developmental outcome at 5 yr was compared in 1031 singleton children of teenage mothers and 10,950 singleton children of older mothers in a national longitudinal study. Children born to teenage mothers and living with them through the first 5 yr performed less well than other children in tests of vocabulary and behaviour at 5 yr of age; they were also shorter on average and had a smaller head circumference. These differences remained significant after allowing for certain social and biological factors, whereas a difference on visuomotor coordination did not. Teenage mothering thus appears somewhat disadvantageous to children's development.  相似文献   
44.
Research on the causes of psychological distress in women in midlife has focused on current adversity and hormonal changes associated with menopause and paid less attention to possible risk factors across the life course. We examined the factors in childhood, adolescence and earlier adult life that show persisting effects on psychological symptoms reported annually over a 6 year period (47-52 years) using prospective data on a cohort of 1500 British women who have been followed since their birth in 1946. Even after taking into account the powerful effect of recent life stress, this study found that women with a high level of psychological distress had different life course trajectories than those with less distress. They were more likely to have scored highly on the neuroticism scale or exhibited antisocial behaviour when they were teenagers, and to have had prior experience of mental and physical health problems in adult life. Those whose parents had divorced reported more distress in midlife, particularly if they too had experienced marital breakdown. These factors accounted for the associations between some of the adult sources of risk, particularly those to do with interpersonal difficulties or poor adult socioeconomic circumstances, and psychological distress in midlife. There was no evidence that concurrent menopausal status had any effect on the level of psychological symptoms except for those women on hormone replacement therapy who had a small and independent additional risk. More attention to a long term temporal perspective is warranted in research on the causes of psychological distress in women at midlife.  相似文献   
45.
Cellular microtubules, polymers of tubulin, alternate relentlessly between phases of growth and shortening. We now show that noscapine, a tubulin-binding agent, increases the time that cellular microtubules spend idle in a paused state. As a result, most mammalian cell types observed arrest in mitosis in the presence of noscapine. We demonstrate that noscapine-treated murine melanoma B16LS9 cells do not arrest in mitosis but rather become polyploid followed by cell death, whereas primary melanocytes reversibly arrest in mitosis and resume a normal cell cycle after noscapine removal. Furthermore, in a syngeneic murine model of established s.c. melanoma, noscapine treatment resulted in an 85% inhibition of tumor volume on day 17 when delivered by gavage compared with untreated animals (P 相似文献   
46.
OBJECTIVES: The purpose of this study was to characterize sexual behavior and opinions about sex in the United States and Britain; implications are discussed for effective public health policy regarding sexually transmitted diseases (STDs) in the United States. METHODS: Large-scale national probability surveys conducted in the 2 countries detailed sexual behavior, opinions, and the prevalence of STDs. RESULTS: In comparison with that of Britain, the US population has greater variability in sexual behavior, less tolerant opinions about sexual behavior, and a higher STD prevalence and lower condom usage among men. CONCLUSIONS: The survey data show compelling evidence from both countries of a strong association between number of sex partners and STD risk. In the United States relative to Britain, there is both greater dispersion in sexual behavior and a greater incidence of unconditional opposition to certain sexual practices. The former implies a need for strong public health policy to address the risks of STDs, but the latter implies strong opposition to that policy. This disjuncture between public health need and feasibility may contribute to the high US rate of STDs.  相似文献   
47.
48.
In recent years planners of health services have been urged to design a comprehensive range of services which are responsive to the needs of people with HIV infection and AIDS and those who might be worried about HIV transmission. Models of care have been tried and tested and pilot services which aim to inform the development of the services scrutinised. Though in general this community care is seen as the preferred option with adequate backup support from acute services. More than anything, there is a recognition that the service must be responsive to local needs. Because patterns of HIV infection and prevalence of AIDS are so variable there is no substitute for the systematic development of timely local knowledge as the basis of local planning.  相似文献   
49.
A long-term follow up of a personal series of 79 second ear stapedectomies indicates that the procedure can be undertaken with minimal complications. No bilateral dead ears or vestibular disasters have occurred. The results were satisfactory in 87.5% of ears, and bilaterally symmetrical hearing with an air-bone gap of 30 dB or less was achieved in 24% of patients. Whilst the established dictum that only one ear should be operated upon should not be abandoned, the results reported in this paper may encourage the more experienced to operate on the second ear at a later date in carefully selected cases.  相似文献   
50.
1 Valproic acid or phenytoin were added to fresh human serum in varying concentrations and their binding characteristics determined by the method of Scatchard (1949). 2 Changes in serum albumin binding were investigated for phenytoin in the presence of 280, 560, 1050 and 2100 mumol l-1 valproic acid, and for valproic acid in the presence of 40, 120, 280 and 480 mumol l-1 phenytoin. 3 Phenytoin appeared to bind to a single site on the albumin molecule and could be competitively displaced from this site by concentrations of valproic acid above 280 mumol l-1. 4 At high concentrations of valproic acid, the affinity of phenytoin for albumin was greatly decreased but the number of available binding sites was increased from one to four. 5 Valproic acid was bound to two high affinity and five low affinity binding sites but the latter were not detectable at valproic acid concentrations below 2100 mumol l-1. 6 Phenytoin displaced valproic acid from its high affinity binding sites, although this was statistically significant only at a concentration of 480 mumol l-1 phenytoin.  相似文献   
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