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241.
242.
McCoy Clyde B. Metsch Lisa R. McCoy H. Virginia Lai Shenghan 《Population research and policy review》1999,18(1-2):71-87
Despite the central role of women drug users in escalating AIDS statistics, there is still a limited number of studies that examine the roles of gender and drug use type in HIV seroprevalence. This lacuna in the research literature has led to significant gaps in researchers' understanding of how and to what extent women may differ in their drug-using and HIV risk behaviors compared to their better-studied male counterparts. This study, derived from a sample of 3,555 out-of-treatment drug users residing in three South Florida urban and rural communities, attempts to compare the drug usage and needle and sexual risk behaviors of male and female drug users that put them at risk for HIV infection. The overall seropositivity rate for women drug users was 26.5% compared to 19.5% for their male counterparts. Results of multivariate analyses indicate that females compared to males were 1.4 times more likely to be HIV seropositive. Risk behaviors associated with this elevated seropositivity include living arrangements, homeless status, drug use, sexual trading behaviors, and history of STDs. Furthermore, there was a strong linear relationship between drug use type and HIV seroprevalence among women drug users. Compared to those who were neither crack smokers nor injectors of illicit drugs, those who were crack smokers only were 2 times more likely to be HIV seropositive, while those who were both crack smokers and injectors were 5 times more likely to be HIV seropositive, and those who were injectors only were 6 times more likely to be HIV seropositive. These findings indicate that among women, drug abuse and its associated risk behaviors, increase the vulnerability of this population for HIV and thus render them an extremely important priority population on which to focus HIV prevention and public health efforts and programs. 相似文献
243.
R. D. Blanchard-Boehm R. A. Earl J. H. Wachter E. J. Hanford 《Population and environment》2008,29(6):292-312
San Antonio, Texas, the seventh largest city in the United States, has experienced steady population growth, since the “boom”
of the 1960s. Projected water shortages due to this growth were realized as early as the 1970s by city leaders and south-central
Texas regional development decision makers. To reduce dependence on the already over-taxed, Edwards aquifer, a solution, the
Applewhite Dam and Reservoir Project, was developed with wide acceptance by federal, state, and city leaders who regarded
the project as a necessary measure for regional growth and development. However, opposition by taxpayer and environmental
groups led to referendums of 1991 and 1994 in which voters blocked construction of the dam and reservoir leaving the city
with limited options for water provision. This case study investigated the factors which led to a clear mismatch in communication
between decision makers—those who were aware of the actual and quantifiable risk to the region in terms of reduced water supplies—and
the general public, a population that did not have complete and/or adequate knowledge of their actual risk regarding future
water shortages, nor, of solutions being developed, such as the Applewhite project. The findings from this case study indicate
that when municipal leadership fails to adequately communicate risk regarding resource shortage to an affected public, as
well as, openly planned solutions, that voters are likely to underestimate future impacts of water shortages, heed last-minute
opposition, and reject long-standing, publicly proposed projects. The intent of this research is not to support either side
in the Applewhite controversy, but to shed perspective on the process of adequately and effectively communicating future water
needs to an at-risk population. Decision makers in cities across the United States who are faced with solving problems of
limited resources needed by a large populace may be informed by the results of this research. 相似文献
244.
The primary purpose of the present experiment was to examine the effects on the empirical derivation of executive's utility functions caused by the use of random device analogues. The results indicate that utility functions obtained using a random device analogue imply more risk aversion than when these functions are determined by simulating actual decision situations. Furthermore, there is also evidence that the bias is directly related to the monetary amounts involved. 相似文献
245.
Melvin R. Crask 《决策科学》1979,10(1):1-15
This paper presents a micro-analytic store choice model which eliminates the assumptions of homogeneity of stores and homogeneity of shoppers found in earlier models. The model simulates individual shopping trips within a shopping center and was successful in predicting the stores chosen by a sample of shopping center patrons. Two earlier models were also tested, but the proposed model performs better than either of the simpler models. Besides its predictive value, the model suggests a number of strategic implications for retailers and shopping center developers and provides a methodology that may be useful in other areas of behavioral research. 相似文献
246.
Aharon R. Ofer 《决策科学》1979,10(2):258-267
The evaluation of the lease versus purchase alternative by not-for-profit hospitals presents a problem that stems from the interaction between investment and financial decisions. This paper provides an analytical framework that resolves this issue by neutralizing the impact of the lease contract on the hospital's financial structure and debt capacity. The formulation incorporates the special operating characteristics of not-for-profit hospitals: namely, they are not subject to federal income tax, and part of their revenue is generated through cost-based reimbursement. 相似文献
247.
The entropy measure H=−σpi log pi is being used with increasing frequency in the analysis of business and economic data. It is, however, simply another measure of dispersion which can be related to the moments of the probability function. Its virtues stem from its decomposition and interpretative properties. This paper surveys the uses to which the measure has been put in the literature, and discusses whether its use has been appropriate and innovative. 相似文献
248.
This paper presents a comparison of two heuristic methods for assigning a part-time work force to meet varying daily work loads. The authors use actual operating data from Purdue National Bank, Lafayette, Indiana, to make teller staffing decisions. The performance criteria for comparison of the two heuristics is the minimum number of workers employed, minimum number of interbranch transfers, and computer time necessary to attain a solution. 相似文献
249.
To provide effective managerial support for decisions related to production planning and scheduling processes, it is useful to partition the set of decisions into a hierarchical framework. In the resulting system, higher level decisions impose constraints on lower level actions, and lower level decisions provide the necessary feed-back to reevaluate higher level actions. The purpose of this paper is to suggest optimum procedures to deal with the resulting subproblems and to analyze the interaction mechanisms among the different hierarchical levels. Computational results are given. 相似文献
250.