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1.
To determine whether methotrexate (MTX) maintains its effectiveness in rheumatoid arthritis (RA) in the setting of community based private rheumatology practice we used life table analysis to review the combined experience of a group of these practices. Of 587 patients with RA who started to take MTX, total termination rate at 70 months was 24.4% with most terminations prompted by drug toxicity. Older age (greater than 65 years) was associated with higher rates of toxicity. Treatment termination rates varied substantially between rheumatologists. We conclude that MTX therapy for RA is well tolerated and maintains effectiveness for at least 70 months.  相似文献   
2.
Crowded motions refer to multiple objects moving around and interacting such as crowds, pedestrians and etc. We capture crowded scenes using a depth scanner at video frame rates. Thus, our input is a set of depth frames which sample the scene over time. Processing such data is challenging as it is highly unorganized, with large spatio‐temporal holes due to many occlusions. As no correspondence is given, locally tracking 3D points across frames is hard due to noise and missing regions. Furthermore global segmentation and motion completion in presence of large occlusions is ambiguous and hard to predict. Our algorithm utilizes Gestalt principles of common fate and good continuity to compute motion tracking and completion respectively. Our technique does not assume any pre‐given markers or motion template priors. Our key‐idea is to reduce the motion completion problem to a 1D curve fitting and matching problem which can be solved efficiently using a global optimization scheme. We demonstrate our segmentation and completion method on a variety of synthetic and real world crowded scanned scenes.  相似文献   
3.
We revisit from a fairness point of view the problem of online load balancing in the restricted assignment model and the 1-∞ model. We consider both a job-centric and a machine-centric view of fairness, as proposed by Goel et al. (In: Symposium on discrete algorithms, pp. 384–390, 2005). These notions are equivalent to the approximate notion of prefix competitiveness proposed by Kleinberg et al. (In: Proceedings of the 40th annual symposium on foundations of computer science, p. 568, 2001), as well as to the notion of approximate majorization, and they generalize the well studied notion of max-min fairness. We resolve a question posed by Goel et al. (In: Symposium on discrete algorithms, pp. 384–390, 2005) proving that the greedy strategy is globally O(log?m)-fair, where m denotes the number of machines. This result improves upon the analysis of Goel et al. (In: Symposium on discrete algorithms, pp. 384–390, 2005) who showed that the greedy strategy is globally O(log?n)-fair, where n is the number of jobs. Typically, n?m, and therefore our improvement is significant. Our proof matches the known lower bound for the problem with respect to the measure of global fairness. The improved bound is obtained by analyzing, in a more accurate way, the more general restricted assignment model studied previously in Azar et al. (J. Algorithms 18:221–237, 1995). We provide an alternative bound which is not worse than the bounds of Azar et al. (J. Algorithms 18:221–237, 1995), and it is strictly better in many cases. The bound we prove is, in fact, much more general and it bounds the load on any prefix of most loaded machines. As a corollary from this more general bound we find that the greedy algorithm results in an assignment that is globally O(log?m)-balanced. The last result generalizes the previous result of Goel et al. (In: Symposium on discrete algorithms, pp. 384–390, 2005) who proved that the greedy algorithm yields an assignment that is globally O(log?m)-balanced for the 1-∞ model.  相似文献   
4.
Interorganizational systems (IOS) may provide substantial benefits, however many organizations are reluctant to implement them. This empirical research takes a novel approach and develops a model of IOS feasibility, which is based on the Theory of Constraints (TOC). It introduces the notion of maximal infeasibility, which is the highest among the values of five factors: economic infeasibility, organizational infeasibility, technological infeasibility, risks, and lack of financial resources. The highest value was selected because implementation is hindered even if only one of the feasibility requirements is not fulfilled. Data collected from 139 medium and large Israeli business organizations validated the model, and indicated that strategic motivation is the main driving force for an organization to initiate or to join an IOS, while the main barriers are organizational infeasibility issues such as lack of management support or uninterested potential partners. Adopting a TOC approach to IOS implementation may assist organizations to overcome these obstacles and increase the chance of a successful implementation. An earlier shorter version of this paper was presented at WEB 2006, a pre-ICIS workshop on e-business, in Milwaukee, WI.  相似文献   
5.
The United Parcel Service (UPS)–Motorola case study revolves around two major areas of information technology (IT) management: IT as a competitive tool and global outsourcing of IT projects. It provides an opportunity to become familiar with the decisions and actions taken by UPS to assure their competitive advantage in the turbulent courier services industry. In the IT outsourcing area, the case addresses managerial and technical issues associated with outsourcing IT projects across the global community. The case presents the specific factors that made this outsourcing project successful and discusses the development of the outsourcing relationships between UPS and Motorola (Israel), from initial negotiations to the creation of a strategic alliance between the two companies. A major point in this case is the gradual development of trust between the two sides, trust that led the two firms from being committed to a contract to becoming strategic partners.  相似文献   
6.
Smell and taste are among the basic senses with which we perceive the world around us. In addition to enabling recognition of chemical moieties that provide social or nutritional clues, taste and smell receptors are expressed in many extraoral tissues, including the gastrointestinal, respiratory, and reproductive systems. It is, therefore, likely that taste and smell receptors have additional physiological roles, which are currently under intensive study. Most of the taste modalities, as well as olfaction, are mediated by G-protein coupled receptors (GPCRs). Recent breakthroughs in crystallography and signaling studies of GPCRs (celebrated by the 2012 Nobel Prize in Chemistry to Robert Lefkowitz and Brian Kobilka) provide excellent opportunities for applying this information towards furthering our understanding of taste and smell signaling. No crystal structures of odorant or taste receptors are currently available. However, computational techniques, many of which stem from the pioneering contributions of the 2013 Nobel Prize in Chemistry laureates, Martin Karplus, Michael Levitt, and Arieh Warshel, can shed light on the function of taste and olfactory GPCRs. In this review, we highlight examples of iterative combinations of simulation and experiment that were successfully applied toward delineating binding modes of tastants and odorants and toward predicting additional ligands. Further studies are required in order to answer remaining questions regarding receptor promiscuity versus selectivity, the details of receptor coupling to G-proteins, and the roles of oligomerization and of allosteric modulation in taste and smell transduction.  相似文献   
7.
This paper proposes a metalanguage for representing communication among participants in a session of a group decision support system (GDSS). Such a vehicle can be used for setting standards and designing specific user interfaces with GDSS.Three different roles of participants are identified: chairperson, chauffeur and regular participant. The tasks and activities of each role are analyzed. Based on the analysis, communications requirements are derived. The requirements lead to a design of a metalanguage consisting of 15 different commands. The paper concludes by displaying the structure and syntax of each command.The work described here is conceptual and could be considered as a proposal for GDSS language design.  相似文献   
8.
The reasons for recent declines in AIDS incidence and mortality may include advances in treatment, but these may be confounded by earlier declines in the incidence of human immunodeficiency virus (HIV) infection. To determine whether the declines in AIDS and mortality may, in part, stem from wider use of combination antiretroviral therapy, 622 HIV-positive men with well-characterized dates of seroconversion were followed. In this group, combination therapy came into widespread use in only 1996. In a Cox proportional hazards model, the 1996 calendar period was significantly associated with slower progression to AIDS (relative hazard [RH]=0. 19, 95% confidence interval [CI], 0.05-0.69, P=.01) and death (RH=0. 45, 95% CI, 0.21-0.95, P=.04). Declines in incidence of HIV infection, changes in HIV virulence, and end-point underreporting cannot fully explain the decline in AIDS and death in 1996. The introduction of combination antiretroviral therapy as the standard of care may already have had measurable effects.  相似文献   
9.
The relationship between peripheral lymphocyte apoptosis and human immunodeficiency virus disease progression was studied in infected subgroups with distinct profiles of progression. Long-term nonprogressors (LTNP) and seronegative controls had levels of spontaneous apoptosis significantly lower than those for recent seroconverters who had CD4 cell counts similar to those of nonprogressors but with a high likelihood of disease progression. Lymphocytes from nonprogressors and seronegative controls also showed negligible spontaneous caspase-3 activity, a biochemical indicator for apoptosis, whereas early progressors exhibited substantial activity. In contrast, when activated with mitogens, the lymphocytes from both LTNP and progressors displayed indistinguishable levels of heightened apoptosis. Spontaneous apoptosis and plasma viremia levels correlated positively in progressors, but not in LTNP. These findings demonstrate that increased lymphocyte apoptosis is evident prior to CD4 T cell decline and that LTNP are relatively resistant to the factors that induce accentuated levels of spontaneous but not mitogen-induced cell death.  相似文献   
10.
OBJECTIVE: To clarify the effect of cigarette smoking on the development of conditions associated with HIV infection. DESIGN: Prospective and retrospective cohort study, with interview and examination twice a year since 1988. METHODS: Data on 516 HIV-infected men from cohorts of homosexual and bisexual men in San Francisco, Denver and Chicago, who were repeatedly interviewed and examined between 1988 and 1992, were analysed. After excluding men who did not have well-defined dates of seroconversion and those who were classified as ex- or intermittent smokers, 232 men remained for analysis: 106 were smokers and 126 were non-smokers. Univariate and Kaplan-Meier survival analyses were performed to assess the relationship between cigarette smoking and loss of CD4+ T-lymphocytes, diagnosis of any AIDS-defining illness, and specific diagnosis of Kaposi's sarcoma, Pneumocystis carinii pneumonia (PCP), oral candidiasis, hairy leukoplakia, and community-acquired pneumonia. RESULTS: By univariate analyses, cigarette smoking was not associated with clinical AIDS, loss of CD4+ cells, Kaposi's sarcoma or PCP, but was significantly associated with oral candidiasis [relative risk (RR), 1.32; 95% confidence interval (CI), 1.02-1.70], hairy leukoplakia (RR, 1.51; 95% CI, 1.15-1.99), and community-acquired pneumonia (RR, 2.62; 95% CI, 1.30-5.27). Dose-response effect was also evident for these three conditions (all P < 0.01). Kaplan-Meier survival analysis indicated no association between cigarette smoking and time of progression to clinical AIDS, Kaposi's sarcoma (KS), or PCP (P = 0.62, 0.54 and 0.11, respectively) but showed that cigarette smokers developed oral candidiasis, hairy leukoplakia, and pneumonia more quickly than non-smokers (P = 0.031, 0.006 and 0.009, respectively). CONCLUSIONS: Cigarette smoking was not associated with an increased likelihood or rate of developing KS, PCP or AIDS, but was associated with developing community-acquired pneumonia, oral candidiasis, and hairy leukoplakia in these HIV-infected men.  相似文献   
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