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91.
The biology of the gray-sided voleClethrionomys rufocanus in Hokkaido, concerning taxonomy, morphology, phylogeny, distribution, and natural history, is reviewed. Applied issues in forest management (damage, control and census) are also mentioned. AlthoughClethrionomys rufocanus of Hokkaido was originally identified as a distinct species,Evotomys (=nowClethrionomys) bedfordiae Thomas, 1905, current literature generally refers to the gray-sided vole of Hokkaido asClethrionomys rufocanus or asC. rufocanus bedfordiae (vernacular name, the Bedford’s red-backed vole). The gray-sided vole is the most common small mammal in Hokkaido. It inhabits open areas as well as forests, and mainly feeds on green plants. The gray-sided vole has a high reproductive potential; litter size: 4–7; gestation period: 18–19 days; maturation age: 30–60 days old. Although spring-born individuals usually attain sexual maturity in their summer/fall of birth, their maturation is sometimes suppressed under high densities. The breeding season is generally from April to October, but with some regional variation.Clethrionomys rufocanus has a rather specialized diet (folivorous), particularly during winter when it feeds on bamboo grass. Many predators specialize on the grey-sided vole in Hokkaido; even the red fox, which is a typical generalist predator, selectively feeds on this vole. Damage by voles’ eating bark used to be sever on forest plantations in Hokkaido. Censuses of small rodents have been carried out for management purpose since 1954.  相似文献   
92.
It is an undeniable fact that resistance training (RT) is a potent stimulus for muscle hypertrophy and strength gain, but it is less understood whether RT can increase maximal aerobic capacity (VO2max). The purpose of this brief review is to discuss whether or not RT enhances VO2max in young (20–40 years) and older subjects (>60 years). Only 3 of 17 studies involving young subjects have indicated significant increases in VO2max following RT, while six of nine studies in older subjects have reported significant improvements in VO2max following RT. There was a significant negative correlation between the initial VO2max and RT-induced change in VO2max. This result suggests that RT-induced increase in VO2max is dependent upon the subject’s initial VO2max. The RT-induced increase in VO2max may be elicited when their initial relative VO2max is lower than 25 ml/kg/min for older subjects and lower than 40 ml/kg/min for young subjects. Thus, RT can be expected to improve concurrently both muscular and cardiovascular fitnesses within a single mode of RT when young and old persons have initially low fitness levels.  相似文献   
93.
Abstract  The Great Hanshin-Awaji earthquake revealed the inadequacy of research in the area of information studies. There is a lack of research on the availability of information on daily life which could alleviate suffering during the reconstruction period. The purpose of this paper is to confirm whether residents receive sufficient information to assist them in making rational decisions during the Great Hanshin-Awaji Earthquake. Our research findings are as follows: (1) People's capacity to send information was very low early in the emergency period. (2) The channel of communication depended on whether people stayed in their own homes or lived elsewhere during the evacuation period. (3) The use of mass media by the aged (both in terms of receiving and sending information) was low. (4) The higher the damage to utilities, the higher was the levels of dissatisfaction with the existing means of information. Most people wished direct communications between the municipality and the victims. (5) Consummatory information on the actual situation was offered effectively by mass media in the stricken area. Similarly important information to support life in the stricken areas was offered by many volunteer groups.  相似文献   
94.
95.
A placebo‐controlled randomized clinical trial is required to demonstrate that an experimental treatment is superior to its corresponding placebo on multiple coprimary endpoints. This is particularly true in the field of neurology. In fact, clinical trials for neurological disorders need to show the superiority of an experimental treatment over a placebo in two coprimary endpoints. Unfortunately, these trials often fail to detect a true treatment effect for the experimental treatment versus the placebo owing to an unexpectedly high placebo response rate. Sequential parallel comparison design (SPCD) can be used to address this problem. However, the SPCD has not yet been discussed in relation to clinical trials with coprimary endpoints. In this article, our aim was to develop a hypothesis‐testing method and a method for calculating the corresponding sample size for the SPCD with two coprimary endpoints. In a simulation, we show that the proposed hypothesis‐testing method achieves the nominal type I error rate and power and that the proposed sample size calculation method has adequate power accuracy. In addition, the usefulness of our methods is confirmed by returning to an SPCD trial with a single primary endpoint of Alzheimer disease‐related agitation.  相似文献   
96.
Clinical trials with event‐time outcomes as co‐primary contrasts are common in many areas such as infectious disease, oncology, and cardiovascular disease. We discuss methods for calculating the sample size for randomized superiority clinical trials with two correlated time‐to‐event outcomes as co‐primary contrasts when the time‐to‐event outcomes are exponentially distributed. The approach is simple and easily applied in practice. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
97.
We attempt to examine the extent to which poverty in childhood adversely affects success in adulthood, using micro data from nationwide surveys in Japan and taking into account the recursive structure of life outcomes. We use retrospective assessments of income class at the age of 15, because longitudinal data on household income are not available. After controlling for its endogeneity, we confirm that children from poor families tend to have lower educational attainment, face higher poverty risks, and assess themselves as being less happy and as suffering from poorer health.  相似文献   
98.
ABSTRACT

This paper reviews and extends the literature on the finite sample behavior of tests for sample selection bias. Monte Carlo results show that, when the “multicollinearity problem” identified by Nawata (1993 Nawata , K. ( 1993 ). A note on the estimation of models with sample-selection biases . Economics Letters 42 : 1524 . [CSA] [CROSSREF] [Crossref], [Web of Science ®] [Google Scholar]) is severe, (i) the t-test based on the Heckman–Greene variance estimator can be unreliable, (ii) the Likelihood Ratio test remains powerful, and (iii) nonnormality can be interpreted as severe sample selection bias by Maximum Likelihood methods, leading to negative Wald statistics. We also confirm previous findings (Leung and Yu, 1996 Leung , S. F. , Yu , S. ( 1996 ). On the choice between sample selection and two-part models . Journal of Econometrics 72 : 197229 . [CSA] [CROSSREF] [Crossref], [Web of Science ®] [Google Scholar]) that the standard regression-based t-test (Heckman, 1979 Heckman , J. J. ( 1979 ). Sample selection bias as a specification error . Econometrica 47 : 153161 . [CSA] [Crossref], [Web of Science ®] [Google Scholar]) and the asymptotically efficient Lagrange Multiplier test (Melino, 1982 Melino , A. ( 1982 ). Testing for sample selection bias . Review of Economic Studies 49 : 151153 . [CSA] [Crossref], [Web of Science ®] [Google Scholar]), are robust to nonnormality but have very little power.  相似文献   
99.
Model‐based phase I dose‐finding designs rely on a single model throughout the study for estimating the maximum tolerated dose (MTD). Thus, one major concern is about the choice of the most suitable model to be used. This is important because the dose allocation process and the MTD estimation depend on whether or not the model is reliable, or whether or not it gives a better fit to toxicity data. The aim of our work was to propose a method that would remove the need for a model choice prior to the trial onset and then allow it sequentially at each patient's inclusion. In this paper, we described model checking approach based on the posterior predictive check and model comparison approach based on the deviance information criterion, in order to identify a more reliable or better model during the course of a trial and to support clinical decision making. Further, we presented two model switching designs for a phase I cancer trial that were based on the aforementioned approaches, and performed a comparison between designs with or without model switching, through a simulation study. The results showed that the proposed designs had the advantage of decreasing certain risks, such as those of poor dose allocation and failure to find the MTD, which could occur if the model is misspecified. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
100.
Yamato Transport Corporation recently entered the parcels business and has been very successful, taking the largest share of the market, in competition with the Japanese Post Office. By the use of a computerized information system, the company provides a rapid high quality service. Yamoto offers a pick up and delivery service. It uses retail stores for receiving the parcels and every driver has a small ‘point of sale’ terminal. The company has built its transportation network systematically, one step at a time.  相似文献   
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