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1.
News wire services were established in the United States in the mid-nineteenth century to gather and distribute news for local newspapers, using the new technology of the telegraph. With that early beginning in the era of electronic communication, the expansion of news wire services spans the change from a society of local communities to a more nationally integrated society. This paper assesses the importanceof changes in the medium's spatial organization which promoted national culture. The first wire services were local, ad hoc groups, organized to achieve greater efficiency in news-gathering. Formal services were first organized on a local basis, but in 1848 they began to sell news to the major urbanized portions of the United States. As the nation grew, the desire for greater efficiency conflicted with the desire for greater autonomy. Regional wire services persisted from the 1860s to the 1880s but after the 1880s, a tenuous national organization was achieved, cementing itself into a national system after the turn of the century. Efficiency in news collection was the primary reason for the increasing scale of news collecting groups. Each step toward larger spatial coverage, fed the growth of a complex interdependent urban system.  相似文献   
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In recent decades the Uruk and Jemdet Nasr periods of the fourth millennium B. C. in Mesopotamia have been the subject of considerable research by scholars of the ancient Near East. Interests in and interpretations of these periods have focused on their credentials as early states, urban societies, and the immediate antecedents of Sumerian civilization. In this overview, I first present a brief historical background on the study of these periods, followed by a critical review of recent approaches that have had significant impacts on current directions of research and understanding of the fourth millennium. Finally, I suggest some research avenues currently being tentatively explored that may be especially appropriate for developing further our understandings of these periods.  相似文献   
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A number of public policy issues have been discussed in this article, the most important of which are: 1. Small business would not need special consideration if our economy were basically a competitive one. 2. A large and growing segment of our economy has sufficient market and political power to make our economy basically non-competitive. 3. Small firms tend to provide price competition, to lead in the development of new products and processes, and to generate new innovations and new employment. 4. Government policy tends to create artificial economies of scale, giving an unwarranted advantage to the very large firm. As a first approximation, a policy of government neutrality on firms of varying size is needed. But, because of discriminations which already exist which favor large firms over small firms, special small business programs may be necessary to provide an equitable policy base. Unfortunately, programs designed to benefit all business, like the investment tax credit, tend to primarily benefit larger firms (Berney, 1979). This is the case for two reasons. First, there is a basic difference in production relationships: large firms tend to be more capital intensive and small firms more labor intensive. Second, the more complex a rule or regulation, the more costly it is for small business to use it. Consequently, even the employment tax credit, which should benefit the small firm is not used by them. Instead, it tends more to benefit the larger firm. Neutrality, as a governmental policy, would appear to demand different treatment for firms of varying size. As an example, the “regulatory flexibility” concept applies different standards to different sized firms so that the burden of regulation is more equitably distributed. The concept of encouraging or requiring financial institutions and other lenders to establish “dual prime rates” is a further example. Since small firms appear to have much higher debt to equity ratios and rely more heavily on shorter-term bank credit, they are more heavily burdened by a tight money policy which forces increases of interest rates. Thus, dual prime rates help to spread the burden of rising interest costs more equally. As many people prefer to work for themselves, equalizing the burden of government policy could only serve to increase the basic growth rate for small business, thus providing an easier start for entrepreneurs and would encourage a more rapid rate of economic growth. None of these discussions, however, argues that small business should be protected from failure. The more efficient firms will succeed and prosper, and the least efficient will not. Many currently successful entrepreneurs learn how to improve their production processes or managerial skills from their failures. What is being recommended as a first step is that government should concentrate on equalizing burdens and benefits in order to achieve true neutrality. If private economies of scale do indeed exist, new firms must grow to survive; what the government should not create are artificial economies of scale with public policy. A strong argument for further action can also be made: it appears that significant external benefits are produced by an economic system with a dynamic small business sector. Since these benefits go to society as a whole rather than entrepreneurs alone in the form of increased profits, a freely operating market without government assistance does not generate as many new small businesses as would be optimal for our society. To internalize the benefits that come from small business, governmental programs need to be devised to increase the rate of return on new, innovative small businesses. Should this happen, we could then anticipate increased rapid rates of innovation and technological change, more rapid rates of employment growth, expanded price competition in all sectors of the economy, and improved export capabilities, in short, true flexibility in our capitalistic system.  相似文献   
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While food allergy prevalence has been studied at the national level, we know little of food allergy prevalence or perceptions of prevalence/management at the local level. This paper uses Waterloo Region as a case study to 1) document self-reported individual and household food allergy and sensitivity prevalence at the local level; 2) investigate perceptions of food allergy prevalence; and 3) explore perceived confidence in anaphylaxis management. Survey data were collected from January to March 2019. Respondents (n = 500) self-reported individual and household food allergy and sensitivity, estimated the percentage of Canadians with food allergy, and were queried about their knowledge of food allergy management. Prevalence estimates were weighted to the structure of the 2016 Canadian Census, and univariate and bivariate analysis were conducted. Prevalence of self-reported food allergy was 12.1% (95%CI, 8.8%-15.3%), and prevalence of self-reported food sensitivity was 26.3% (95%CI, 21.9%-30.7%). When asked to estimate the percentage of Canadians with food allergy, the mean perceived percentage was 35.1% (SD = 22.96). Self-reported prevalence of food allergy appears higher in Waterloo Region, and the estimated percentage of Canadians with food allergy is inflated. Understanding prevalence and perceptions at the local level is important for targeted allocation of public health resources to ensure safe spaces for individuals with food allergy.  相似文献   
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Agentes de su propia libertad. Los esclavos de Lima y la desintegración de la esclavitud, 1821–1854. By CARLOS AGUIRRE. Lima: Fondo Editorial Universidad Católica, 1993. Pp. 333.

Slavery and Abolition in Early Republican Peru. By PETER BLANCHARD. Delaware: Scholarly Resources, 1992. Pp. xx, 247.

Paying the Price of Freedom: Family and Labor among Lima's Slaves, 1800–1854. By CHRISTINE HÜNEFELDT. Berkeley: University of California Press, 1994. Pp. xi, 269.

Safari africano y compra‐venta de esclavos para el Perú (1412–1818). By FERNANDO ROMERO. Lima: IEP‐UNSCH, 1994. Pp. 275.  相似文献   

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Relatively little is known about the possibilities and limitations of voluntary public programs. The so-called 33/50 Program for reducing releases of certain toxic chemicals into the environment provides a useful instance for examination. In an investigation of toxics-reduction outcomes, with states as units of analysis, economic and policy variables help to explain the results. In particular, channels and approaches used In communicating policy intentions are related to outcomes. Voluntary programs can make a difference, but the details of execution, including the extent and nature of field efforts, influence outcomes.  相似文献   
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It is shown that audience members actively select amongst available programmes on television. This selection is based upon the social role and situational characteristics of the viewer and it is also directly related to the reasons given by viewers for watching television.

Patterns of programme selection are related to three clusters of needs and reasons. The two most important of these are composed of needs relating to information and diversion. The least important cluster is concerned with the self and social contact.

Escape and diversion needs are satisfied by almost any programme; selection is minimal by those viewers expressing these needs. Information needs are best satisfied by news and other informational programmes, while social and self needs are best satisfied by quiz and variety programmes, popular drama and movies.  相似文献   

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