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81.
To inform local and regional decisions about protecting short-term and long-term quality of life, the Consortium for Atlantic Regional Assessment (CARA) provides data and tools (for the northeastern United States) that can help decision makers understand how outcomes of their decisions could be affected by potential changes in both climate and land use. On an interactive, user-friendly website, CARA has amassed data on climate (historical records and future projections for seven global climate models), land cover, and socioeconomic and environmental variables, along with tools to help decision makers tailor the data for their own decision types and locations. CARA Advisory Council stakeholders help identify what information and tools stakeholders would find most useful and how to present these; they also provide in-depth feedback for subregion case studies. General lessons include: (1) decision makers want detailed local projections for periods short enough to account for extreme events, in contrast to the broader spatial and temporal observations and projections that are available or consistent at a regional level; (2) stakeholders will not use such a website unless it is visually appealing and easy to find the information they want; (3) some stakeholders need background while others want to go immediately to data, and some want maps while others want text or tables. This article also compares what has been learned across case studies of Cape May County, New Jersey, Cape Cod, Massachusetts, and Hampton Roads, Virginia, relating specifically to sea-level rise. Lessons include: (1) groups can be affected differently by physical dangers compared with economic dangers; (2) decisions will differ according to decision makers' preferences about waiting and risk tolerance; (3) future scenarios and maps can help assess the impacts of dangers to emergency evacuation routes, homes, and infrastructure, and the natural environment; (4) residents' and decision makers' perceptions are affected by information about potential local impacts from global climate change.  相似文献   
82.
83.
The skin is a route of exposure that needs to be considered when conducting a risk assessment. It is necessary to identify the potential for dermal penetration by a chemical as well as to determine the overall importance of the dermal route of exposure as compared with inhalation or oral routes of exposure. The physical state of the chemical, vapor or liquid, the concentration, neat or dilute, and the vehicle, lipid or aqueous, is also important. Dermal risk is related to the product of the amounts of penetration and toxicity. Toxicity involves local effects on the skin itself and the potential for systemic effects. Dermal penetration is described in large part by the permeability constant. When permeability constants are not known, partition coefficients can be used to estimate a chemical's potential to permeate the skin. With these concepts in mind, a tiered approach is proposed for dermal risk assessment. A key first step is the determination of a skin-to-air or skin-to-medium partition coefficient to estimate a potential for dermal absorption. Building a physiologically-based pharmacokinetic (PBPK) model is another step in the tiered approach and is useful prior to classical in vivo toxicity tests. A PBPK model can be used to determine a permeability constant for a chemical as well as to show the distribution of the chemical systemically. A detailed understanding of species differences in the structure and function of the skin and how they relate to differences in penetration rates is necessary in order to extrapolate animal data from PBPK models to the human. A study is in progress to examine anatomical differences for four species.  相似文献   
84.
Marriage and fertility in the United States have become less firmly entwined as more women bear children without marrying and more couples with children divorce. Today a sizeable number of children are expected to spend a portion of their childhood in one-parent households. Despite the trends in illegitimacy and divorce, the actual effect of out-of-wedlock childbearing on the living arrangements of children has not been fully explicated. Using the National Survey of Family Growth Cycle III, this paper estimates the probability that children aged 0–13 in 1982 are living in two-parent households, controlling for their mothers' marital statuses at their births. We find that marital status at birth is an important predictor of household structure at later ages for both white and black populations; however, the childhood environment is actually quite elastic as women marry, divorce, remarry, and redivorce.  相似文献   
85.
In the design of experiments for estimating the slope of a response surface, slope-rotatability is a desirable property. In this paper, a measure is introduced that enables us to assess the degree of slope-rotatability for a given response surface design. The measure takes the value zero if and only if the design is slope-rotatable, and becomes larger as the design deviates from a slope-rotatable design. Examples of applying this measure to some response surface designs are also given.  相似文献   
86.
This paper documents situations where the variance inflation model for outliers has undesirable properties. The model is commonly used to accommodate outliers in a Bayesian analysis of regression and time series models. The alternative approach provided here does not suffer from these undesirable properties but gives inferences similar to those of the variance inflation model when this is appropriate. It can be used with regression, time series, and regression with correlated errors in a unified way, and adheres to the scientific principle that inference should be based on the data after obvious outliers have been discarded. Only one parameter is required for outliers; it is interpretable as the a priori willingness to remove observations from the analysis.  相似文献   
87.
In multiple linear regression analysis, each observation affects the fitted regression equation differently and has varying influences on the regression coefficients of the different variables. Chatterjee & Hadi (1988) have proposed some measures such as DSSEij (Impact on Residual Sum of Squares of simultaneously omitting the ith observation and the jth variable), Fj (Partial F-test for the jth variable) and Fj(i) (Partial F-test for the jth variable omitting the ith observation) to show the joint impact and the interrelationship that exists among a variable and an observation. In this paper we have proposed more extended form of those measures DSSEIJ, FJ and FJ(I) to deal with the interrelationships that exist among the multiple observations and a subset of variables by monitoring the effects of the simultaneous omission of multiple variables and multiple observations.  相似文献   
88.
Mortality data are often gathered using 5-year age groups rather than individual years of life. Furthermore, it is common practice to use a large open-ended interval (such as 85 and over) for mortality data at the older ages. These limitations of the data pose problems for the actuary or demographer who wishes to compile a full and accurate life table using individual years of life. The author devises formulae which handle these problems. He also devises methods for handling mortality during the 1st year of life and for dealing with other technical problems which arise in the compilation of the full life table from grouped data.  相似文献   
89.
This paper examines the situation and problems of migration on family structure, with emphasis on family reunification. The study is based on conditions and practices in Western Europe and Mediterranean countries relating to temporary labor migration. Most migrant workers have no intention of settling permanently and return to their country within a few years. The International Labour Office estimated in 1974 that at least 1/2 the migrant workers in Western Europe live without their families. Generally, migrants send for their families only when they are employed, earning adequate wages, and have adequate housing. Some reasons why migrants live apart from their families include 1) the receiving country discourages family immigration because it does not coincide with the economic necessities of migration policy and 2) some sending countries discourage it to ensure that the migrant worker returns to his own country. The main danger arising from family separation is that it frequently leads to the break up of the family. The leading European authorities recognize as a fundamental right the freedom of a migrant worker and his family to lead a normal family life in the receiving country. The author outlines the conditions for admission for residence and employment of migrant spouses and children for the Federal Republic of Germany, France, Belgium, Switzerland, the Netherlands, Sweden, Norway, Austria, Luxembourg, and the United Kingdom. All countries require that the head be in regular employment for some time and be able to provide his family with suitable housing. Other problems concerning the arrival of migrant spouses and children include 1) acquiring employment and social information and counseling, 2) education of children, 3) obtaining vocational training and adaptation and 4) achieving entitlement to social security benefits. The effects of migration in the family context in sending countries include 1) providing activities for migrants to maintain cultural links with their countries of origin and 2) acquiring the nationality of the receiving countries. Countries should facilitate the admission to employment of migrant spouses and children, by maintaining provisions for the reuniting of families and imposing no limits on admission to residence; and 2) by overcome obstacles to admission to employment, by observing existing recommendations. In conclusion, governments should give family cohesion 1st priority, regardless of regulations.  相似文献   
90.
To assess the validity and clinical utility of the marital inventory ENRICH, a discriminant validity study was conducted using a national sample of 5039 married couples. The sample was randomly split in order to form a cross-validation group. ENRICH is a multidimensional scale and two types of analysis were conducted to assess the value of these various scales. Results from discriminant analysis indicated that using either the individual scores or couples' scores, happily married couples could be discriminated from unhappily married couples with 85–95% accuracy. These results were cross-validated with a second sample. Using regression analysis, it was clearly demonstrated that background factors account for little of the variance in discriminating happy from unhappily married couples compared to their relationship dynamics, i.e., scale scores. All ENRICH scales except equalitarian roles proved significant, indicating the validity of a multidimensional inventory.  相似文献   
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