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981.
Expanding longevity among the elderly and fertility decline are contributing to an aging US population. The number of persons 65 years or older is projected to double from about 32 million in 1990 to 66 million by 2030; the elderly proportion is expected to increase from 13 to 22 percent over the same period. Chronic illness and functional disability afflicts a significant proportion of older persons. An estimated 80–85 percent of people over age 65 have at least one chronic illness, and nearly one-half of older people report that chronic illness limits their activity to some degree. Altogether, about one-third of the population over 65 may need some kind of medical or social assistance. This paper discusses the three primary modes of care available to older persons: (1) the informal network of the family, (2) the more formal arrangements of home and community care, and (3) the institutionalized care of nursing homes. Of particular policy interest are the questions: Who provides the care? What type of care is available? Who receives the care? How much does each type of care cost? and Who pays? The current patterns and costs especially of long-term care provide a framework for planning future options. A discussion of research and policy recommendations concludes the paper.  相似文献   
982.
African-American marriage in 1910: Beneath the surface of census data   总被引:1,自引:0,他引:1  
This paper examines the quality of information about marital status, marital duration, and marriage order among African-American women in the U.S. Census of 1910. It compares the reported prevalence of widowhood to estimates of widowhood based on the mortality of black men and on the ages of women at first marriage. It also compares the reported distributions of duration of first marriage to estimates based on mortality and on age at first marriage. It concludes that census reports are subject to serious error. Widowhood is overreported, and marital turnover appears to have been faster than implied by census reports. The prevalance of "own children" is used to confirm these conclusions and to suggest motivations for misreporting.  相似文献   
983.
984.
A responsible and comprehensive policy of in vitro fertilization should be preceded by the gathering of empirical information about the application of the procedure in the 138 IVF centers across the country. To date, attention has been directed more to the implications of IVF as a whole than to actual behaviors in the medical community. It is appropriate to survey patients and physicians, examine consent forms, and study guidelines issued by the medical community in order to enhance public knowledge of what has been done voluntarily in the medical community and what remains to be done. Moreover, consumers should be encouraged to speak about their experiences and other groups encouraged to act as advocates for affirmative IVF policy. At present, the interest group spectrum is skewed by physicians' interests groups (speaking for IVF) and other interest groups criticizing the technique. Organized advocates for affirmative IVF policy are less well represented.  相似文献   
985.
    
Summary Experimental results, and interpretation, are presented which relate to oviposition behaviour in four species of parasitic wasp (Hymenoptera: Chalcidoidea). All lay their eggs in pupae of the common house fly (Musca domestica) and of other flies associated with man. Probability models suggested byD. J. Daley for describing the avoidance of superparasitism are used to analyse the data. Certain of the models considered by previous authors appear as specieal cases. A satisfactory fit was obtained either by assuming a fixed probability of oviposition in an already parasitised pupa, or by using a model motivated by supposing that a female will tolerate without oviposition some fixed number of visits to already parasitised pupae. A third model was considered which makes the probability depend on the number of previous ovipositions in the pupae now visited. In all four species the presence of other females (with parasite: host ratio unchanged) increased the probability of oviposition upon encountering an already parasitised pupa. In the presence of other femalesSpalangia endius laid an increased number of eggs, whereas the other three species laid fewer eggs.  相似文献   
986.
In literature serious attention is rarely paid to the theme of "the boy in art," although many artists used and still use boys as a medium for their message. By a detailed analysis of the symbolism in a series of paintings by Ferdinand Hodler (1853-1918), the author attempts a reinterpretation of the pictures this Swiss artist made of his young son Hector. The author rejects traditional Freudian speculations and uses a hitherto neglected and repudiated source for understanding Hodler's symbolism, the social and artistic ideas of a circle of Rosicrucians to which the painter adhered.  相似文献   
987.
Levy and Booth present previously unpublished infant mortality rates for the Marshall Islands. They use an indirect method to estimate infant mortality from the 1973 and 1980 censuses, then apply indirect and direct methods of estimation to data from the Marshall Islands Women's Health Survey of 1985. Comparing the results with estimates of infant mortality obtained from vital registration data enables them to estimate the extent of underregistration of infant deaths. The authors conclude that 1973 census appears to be the most valid information source. Direct estimates from the Women's Health Survey data suggest that infant mortality has increased since 1970-1974, whereas the indirect estimates indicate a decreasing trend in infant mortality rates, converging with the direct estimates in more recent years. In view of increased efforts to improve maternal and child health in the mid-1970s, the decreasing trend is plausible. It is impossible to estimate accurately infant mortality in the Marshall Islands during 1980-1984 from the available data. Estimates based on registration data for 1975-1979 are at least 40% too low. The authors speculate that the estimate of 33 deaths per 1000 live births obtained from registration data for 1984 is 40-50% too low. In round figures, a value of 60 deaths per 1000 may be taken as the final estimate for 1980-1984.  相似文献   
988.
989.
990.
Approximation of molar crowding found in urban centers was studied by using a 2 × 2 × 2 × 2 factorial design. The study involved the simultaneous variation of social density, spatial density, noise, and personality as they affect room affect (physical and psychological). Subjects were 88 undergraduate males pre-tested on the Rotter I-E scale. Other measures used were Marshall's Privacy Preference and Noise Tolerance scales. A scale of Perceptions of the Room was also administered. Results showed main effects of locus of control and spatial density on overall room affect. A Noise × Density interaction approached significance with respect to physical room affect. A main effect of spatial density on physical room affect was also found. Psychological room affect was influenced by spatial density. Theoretical explanations of the results are discussed in terms of dissonance theory, Altman's Social Interaction Model, and the authors' extension of the Worchel and Teddlie two-step model of crowding. It is suggested that introduction of the concept of "appropriate" or "dissonant" space might explain these results and add to our understanding of crowding.Reprint requests should be directed to Ms. Bharucha-Reid.  相似文献   
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