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61.
Mutations in the muscle protein titin have been linked to dilated cardiomyopathy, a condition in which the heart chambers are enlarged and blood is ineffectively pumped, in humans and in animal models. This protein, which is a component of sarcomeres, provides essential scaffolding for other muscle proteins and acts as a spring to confer passive elasticity on the cardiomyocyte. Several titin isoforms exist, and they display varying size and degrees of elasticity. We review two interesting reports that show how variations in titin isoforms might be implicated in cardiac failure.  相似文献   
62.
Using an increasing returns specification for distribution, an inverted U pattern between the share of distribution in gross domestic product and the level of development is shown to arise. A cross-section time-series data set is constructed and merged with one used to analyze the service sector. In contrast to the rising pattern found for services, an average time-series relation that exhibits an inverted U pattern is established. The empirical results are robust, for example, to choice of functional form and country and time period coverage. A similar pattern is found in the average cross-section (country) relation between distribution and development.  相似文献   
63.
Correspondence to Dr Roger Manktelow, School of Social and Community Sciences, University of Ulster Magee College, Derry, BT48 7JL, Northern Ireland. Summary This article reports on the first extensive survey of ApprovedSocial Worker (ASW) activity under the Mental Health (NorthernIreland) Order 1986. The integrated health and social servicesorganizational structure, the adverse effects on individualmental health of the legacy of thirty years of civil conflictand the move from hospital to community care are significantfeatures which have influenced the delivery of mental healthsocial work services locally. The practice and experience ofASWs was surveyed by postal questionnaire and user and carerexperience of compulsory hospital admission was investigatedby a series of focus groups. The study revealed that two-thirdsof ASWs had experience of acting as an applicant in compulsoryhospital admission during the past two years. Nearly half (42per cent) of these ASWs had reported experience of between oneand five admissions and one-tenth had completed over twentyadmissions in the two-year period. In only a small minorityof cases did joint face-to-face assessment with the GeneralPractitioner (doctor) take place; nearly half of ASWs reporteddifficulties in obtaining transport; and only one-fifth of ASWshad experience of acting as a second approved social worker.Half of ASWs reported experience of guardianship, either asapplicant or in making the recommendation. Both service usersand carers reported a lack of understanding about the role ofthe ASW and complained about the lack of alternative resourcesthat ASWs could use to prevent hospital admissions. These findingsare discussed and a number of recommendations are proposed forimprovements to approved social worker practice.  相似文献   
64.
The purpose of this study was to determine the number of residents requiring corrective lenses in a youth detention center for juveniles from 12 to 18 years old over a 2-year period. A greater number of adolescents incarcerated for criminal activity in a detention center had uncorrected refractive errors (34.87 %) as compared to a comparable population in the public school system (22 %). The prevalence of significant refractive errors among incarcerated adolescents in this study is significantly higher than has been reported previously. The current study found a refractive error rate of almost 35 %. This difference can be explained by a number of factors in their social environments and identifies an area for potential intervention to reduce antisocial behavior in this population.  相似文献   
65.
Measurement of non-randomness in spatial distributions   总被引:4,自引:0,他引:4  
Summary The measurement of departure from randomness in spatial distributions has widespread application in ecological work. Several “indices of non-randomness” are compared with regard to their dependence on sample number, sample size and density. Criteria for the best choice of index for specific situations are discussed. A new coefficientC x is proposed for use with positively contagious distributions and tests of significance are given. WhenC x and another index (S 2/m−1) are used for positive and negative contagion respectively, values ranging from −1 through 0 (random) to +1 are obtained, regardless of sample number, sample size or density.  相似文献   
66.
Interoutsourcing is a round‐way process in which the vendor is its customer's customer and the customer is its vendor's vendor. While interoutsourcing is emerging as a prominent outsourcing strategy in many industries, there are no rigorous analytical studies focusing on this mechanism. In this article, we analytically demonstrate the efficacy of interoutsourcing by comparing it with normal outsourcing. Our results show that, compared with normal outsourcing, interoutsourcing acts as a self‐enforcer of vendor firms' behaviors toward increasing outsourcing service value. However, in situations where there is a mismatch of outsourcing activities, a high degree of incentive that is based on outsourcing service value, and a high cost of capital, interoutsourcing is not preferred to normal outsourcing. We discuss these results in detail and provide managerial implications for firms involved in interoutsourcing decisions.  相似文献   
67.
To develop a quantitative exposure‐response relationship between concentrations and durations of inhaled diesel engine exhaust (DEE) and increases in lung cancer risks, we examined the role of temporal factors in modifying the estimated effects of exposure to DEE on lung cancer mortality and characterized risk by mine type in the Diesel Exhaust in Miners Study (DEMS) cohort, which followed 12,315 workers through December 1997. We analyzed the data using parametric functions based on concepts of multistage carcinogenesis to directly estimate the hazard functions associated with estimated exposure to a surrogate marker of DEE, respirable elemental carbon (REC). The REC‐associated risk of lung cancer mortality in DEMS is driven by increased risk in only one of four mine types (limestone), with statistically significant heterogeneity by mine type and no significant exposure‐response relationship after removal of the limestone mine workers. Temporal factors, such as duration of exposure, play an important role in determining the risk of lung cancer mortality following exposure to REC, and the relative risk declines after exposure to REC stops. There is evidence of effect modification of risk by attained age. The modifying impact of temporal factors and effect modification by age should be addressed in any quantitative risk assessment (QRA) of DEE. Until there is a better understanding of why the risk appears to be confined to a single mine type, data from DEMS cannot reliably be used for QRA.  相似文献   
68.
The International Agency for Research on Cancer (IARC) in 2012 upgraded its hazard characterization of diesel engine exhaust (DEE) to “carcinogenic to humans.” The Diesel Exhaust in Miners Study (DEMS) cohort and nested case‐control studies of lung cancer mortality in eight U.S. nonmetal mines were influential in IARC's determination. We conducted a reanalysis of the DEMS case‐control data to evaluate its suitability for quantitative risk assessment (QRA). Our reanalysis used conditional logistic regression and adjusted for cigarette smoking in a manner similar to the original DEMS analysis. However, we included additional estimates of DEE exposure and adjustment for radon exposure. In addition to applying three DEE exposure estimates developed by DEMS, we applied six alternative estimates. Without adjusting for radon, our results were similar to those in the original DEMS analysis: all but one of the nine DEE exposure estimates showed evidence of an association between DEE exposure and lung cancer mortality, with trend slopes differing only by about a factor of two. When exposure to radon was adjusted, the evidence for a DEE effect was greatly diminished, but was still present in some analyses that utilized the three original DEMS DEE exposure estimates. A DEE effect was not observed when the six alternative DEE exposure estimates were utilized and radon was adjusted. No consistent evidence of a DEE effect was found among miners who worked only underground. This article highlights some issues that should be addressed in any use of the DEMS data in developing a QRA for DEE.  相似文献   
69.
This study names a pantheon of entrepreneurs and managers who have introduced a range of far‐reaching productivity innovations throughout modern history. The thread tying together all of the innovations, in whatever sector of the economy one examines, is the theory of swift, even flow. The study argues why swift, even flow explains the power and long‐lasting nature of these innovations and why other factors thought by some to affect productivity fall short.  相似文献   
70.
The term ‘end-to-end’ process management is now commonplace in the language and practice of operations. Managers are encouraged to migrate from functional process management to end-to-end process management to realise a range of performance improvements. However, these improvements are often elusive; the specific challenges associated with such a migration are under-researched. This paper uses a cross-sector study to identify the challenges of end-to-end process management and to generate practical managerial guidance. Three areas are identified that demand particular managerial attention: the need to move beyond process mapping, the role of IT in process management and maintaining the process infrastructure as a strategic asset. More significantly, the findings highlight the need for greater conceptual clarity regarding the end-to-end concept itself. The existing literature suggests that scope is the primary differentiator of the end-to-end process – the requirement to manage an extended boundary from customer order through to customer fulfilment. However, this research suggests that the end-to-end concept is more complex, comprising of three core constructs with seven dimensions: scope (boundary conditions, sequence/flow and controls); scale (resources and input/output transformation) and complexity (interrelationships and orientation). End-to-end process management involves much more than an extended boundary. It requires a systemic perspective and clarity regarding controls and transforming resources.  相似文献   
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