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991.
Onychomycosis is a common and difficult to treat infection, owing predominately to the limited penetration of topical drugs to the site of infection. Systemic drugs are not an option for all patients due to adverse events and drug-drug interactions. In this article, we review the nail penetration and clinical efficacy data of topical drugs, including older agents such as ciclopirox and amorolfine, as well as the newer agents, efinaconazole and tavaborole. Additionally, we describe some unresolved questions in the management of onychomycosis.  相似文献   
992.
Nurses account for approximately 50 % of total hospital budgets and their allocation to medical units and shifts can significantly affect the quality of care provided to patients. The adoption of flexible shift schedules and the assessment of actual nursing time can enable sensible resource planning, balancing the quality of care with efficiency in resource use. Starting from the concept that nurse requirements are triggered by patient needs, which are stochastic in nature both for clinical activities and their duration, this paper proposes an innovative Nurse Requirement Planning model grounded on the concept of the clinical pathway (the “standard” sequence of diagnostic, therapeutic and care activities a patient with certain pathology should undertake over time) with its inner routing probability and patient dependence on nurses, which can be correlated to the time needed to perform nursing tasks. In merging and modelling these two aspects, the method summarizes the best features of acuity-quality and timed-task/activity techniques, well known although not usually applied for reasons of demands on clinicians’ time. Instead, in this paper, for each shift of the day, hospital management is enabled to choose the optimal number of nurses to meet actual requirements according to a desired service level and personnel saturation by means of a tool that simulates the patient flow in a medical unit based on automatic data retrieval from hospital databases. The validation and verification of the proposal were undertaken in a stroke unit.  相似文献   
993.
We present an inquiry-based curriculum based on the digital evolution platform Avida-ED (http://avida-ed.msu.edu). We designed an instructional sequence and lab book consisting of an introduction to Avida-ED and a set of three lessons focused on specific evolutionary concepts. These served to familiarize students with experimental evolution and Avida-ED. Students then developed independent Avida-ED research projects to test their own questions. Curriculum design and implementation occurred over the course or two semesters, with a pilot implementation in the first semester, followed by curriculum revision and full implementation in the second semester. The curriculum was implemented in an undergraduate Introductory Cell and Molecular Biology course at a major research university. Full implementation of the curriculum in semester two involved the use of Avida-ED mainly in the teaching lab in parallel with a bacterial antibiotic resistance experimental research stream, allowing students to draw connections between Avidian digital evolution and the evolution of antibiotic resistance in microbial populations. After carrying out the introductory exercises, students developed independent Avida-ED projects to test their own research questions, and presented their data to researchers in the NSF-funded BEACON Center for the Study of Evolution in Action. Preliminary results of our studies to assess the impacts of an Avida-ED curriculum indicate a positive effect on student learning of evolutionary concepts, particularly in increasing the level of complexity of student explanations about the random nature of mutation.  相似文献   
994.
Grasslands enrolled in the Conservation Reserve Program (CRP) serve as one of the potential national herbaceous resources for use as a dedicated bioenergy feedstock. The goal of this project was to assess the yield potential and suitability of CRP grassland as a bioenergy feedstock source across the USA in regions with significant CRP land resources. In addition to that goal, one major objective of this project was to assess vegetation composition changes that also occurred on these different CRP grasslands over time with different harvest and fertilization management strategies. Three levels of nitrogen fertilization (0, 56, and 112 kg ha?1) and two harvest timings [peak standing crop (PSC) or end of growing season (EGS)] were evaluated for effects on biomass production and resulting species composition changes. Three sites in regions containing concentrated tracts of CRP grassland and representing variable climatic parameters were analyzed for vegetation composition trends over the course of six growing seasons (2008–2013). Specifically, a mixture of warm-season perennial grasses was evaluated in Kansas (KS), while a cool-season mixture was evaluated in Missouri (MO). North Dakota (ND) contained a mixture of both warm- and cool-season grasses. At the MO and KS sites, nitrogen fertilization significantly altered the grass and legume composition over time by lowering the legume percentage in the stand. In KS and ND, the two sites with warm-season grasses, harvesting in mid-summer at PSC, greatly reduced warm-season grass composition over time in favor of annual cool-season grass invaders or perennial cool-season grasses. Any shift to less desirable or less productive species limits the ability of these lands to provide a sustainable or reliable feedstock for bioenergy production.  相似文献   
995.
This work investigated the optimization of sugar and chemical formation from marine macro-green-alga Enteromorpha intestinalis by hydrothermal reaction and a statistical methodology. By this approach, the highest sugar and chemical yields were predicted as follows: glucose 10.42 %, xylose-mannose-galactose (XMG) 18.08 %, total reducing sugar (TRS) 28.61 % (reaction temperature 156 °C, catalyst amount 1.3 %, reaction time 11.4 min), levulinic acid 4.00 % (175.0 °C, 3.7 %, 35 min), 5-hydroxymethylfurfural 1.71 % (186.0 °C, 1.1 %, 37.9 min), and furfural 2.03 % (183.1 °C, 2.2 %, 10.7 min). In terms of the combined severity factor (CSF), the glucose, XMG, and TRS production decreased linearly with increasing CSF and to a high correlation. This application of a marine green-alga shows a high potential for production of fermentable sugars and chemicals suitable for biorefinement processes.  相似文献   
996.
Tactical planning in hospitals involves elective patient admission planning and the allocation of hospital resource capacities. We propose a method to develop a tactical resource allocation and patient admission plan that takes stochastic elements into consideration, thereby providing robust plans. Our method is developed in an Approximate Dynamic Programming (ADP) framework and copes with multiple resources, multiple time periods and multiple patient groups with uncertain treatment paths and an uncertain number of arrivals in each time period. As such, the method enables integrated decision making for a network of hospital departments and resources. Computational results indicate that the ADP approach provides an accurate approximation of the value functions, and that it is suitable for large problem instances at hospitals, in which the ADP approach performs significantly better than two other heuristic approaches. Our ADP algorithm is generic, as various cost functions and basis functions can be used in various hospital settings.  相似文献   
997.
Chemical 2,3-butanediol is an important platform compound possessing diverse industrial applications. So far, it is mainly produced by using petrochemical feedstock which is associated with high cost and adverse environmental impacts. Hence, finding alternative routes (e.g., via fermentation using renewable carbon sources) to produce 2,3-butanediol are urgently needed. In this study, we report a wild-type Klebsiella sp. strain XRM21, which is capable of producing 2,3-butanediol from a wide variety of carbon sources including glucose, sucrose, xylose, and glycerol. Among them, fermentation of sucrose leads to the highest production of 2,3-butanediol. To maximize the production of 2,3-butanediol, fermentation conditions were first optimized for strain XMR21 by using response surface methodology (RSM) in batch reactors. Subsequently, a fed-batch fermentation strategy was designed based on the optimized parameters, where 91.2 g/L of 2,3-butanediol could be produced from substrate sucrose dosing in 100 g/L for three times. Moreover, random mutagenesis of stain XMR21 resulted in a highly productive mutant strain, capable of producing 119.4 and 22.5 g/L of 2,3-butanediol and ethanol under optimized fed-batch fermentation process within 65 h with a total productivity of 2.18 g/L/h, which is comparable to the reported highest 2,3-butanediol concentration produced by previous strains. This study provides a potential strategy to produce industrially important 2,3-butanediol from low-cost sucrose.  相似文献   
998.
Plant biomass offers a renewable and environmentally favorable source of sugars that can be converted to different chemicals, second-generation ethanol, and other liquid fuels. Cellulose makes up approximately 45 % of the dry weight of lignocellulosic biomass. Prior to the enzymatic hydrolysis of cellulose, lignin and hemicellulose must be structurally altered or removed, at least in part, by chemical and/or physical pretreatments. However, the high cost and low efficiency of the enzymatic hydrolysis prevent the process from being economically competitive. For this reason, it is necessary to find enzymes suitable for this type of process, with higher specific activities and greater efficiency. Members of the Bacillus and Paenibacillus genera have been traditionally used for the production of many enzymes for industrial applications. Cellulases produced by both genera have shown activity on soluble and crystalline cellulose and high thermostability and/or activity over a wide pH spectrum. In this review, the most recent information about the characterization of cellulolytic enzymes obtained from new strains of the Bacillus and Paenibacillus genera are reviewed. We focused on the variety of isoenzymes produced by these cellulolytic strains, their optimal production and reaction conditions, and their kinetic parameters and biotechnological potential.  相似文献   
999.
Various software packages for project management include a procedure for resource-constrained scheduling. In several packages, the user can influence this procedure by selecting a priority rule. However, the resource-allocation methods that are implemented in the procedures are proprietary information; therefore, the question of how the priority-rule selection impacts the performance of the procedures arises. We experimentally evaluate the resource-allocation methods of eight recent software packages using the 600 instances of the PSPLIB J120 test set. The results of our analysis indicate that applying the default rule tends to outperform a randomly selected rule, whereas applying two randomly selected rules tends to outperform the default rule. Applying a small set of more than two rules further improves the project durations considerably. However, a large number of rules must be applied to obtain the best possible project durations.  相似文献   
1000.
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