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The importance of phosphonoamidate prodrugs (ProTides) of acyclic nucleoside phosphonate (ANPs) is highlighted by the approval of Tenofovir Alafenamide Fumarate for the treatment of HIV and HBV infections. In the present paper we are reporting an expedient, one-pot, two-steps synthesis of allyl phosphonoamidates and diamidates that offers a time saving strategy when compared to literature methods. The use of these substrates in the cross metathesis reactions with alkenyl functionalised thymine and uracil nucleobases is reported. ANPs prodrugs synthesized via this methodology were evaluated for their antiviral activities against DNA and RNA viruses. It is anticipated that the use of 5,6,7,8-tetrahydro-1-napthyl as aryloxy moiety is capable to confer antiviral activity among a series of otherwise inactive uracil ProTides.  相似文献   
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The International Journal of Life Cycle Assessment - Social sustainability may be assessed using a variety of methods and indicators, such as the social footprint, social impact assessment, or...  相似文献   
996.

Purpose

The aim of this article is to present the first life cycle assessment of chitosan production based on data from two real producers located in India and Europe. The goal of the life cycle assessment (LCA) was to understand the main hot spots in the two supply chains, which are substantially different in terms of raw materials and production locations.

Methods

The LCA is based on consequential modelling principles, whereby allocation is avoided by means of substitution, and market mixes include only flexible, i.e. non-constrained suppliers. The product system is cradle to gate and includes the production of raw materials, namely waste shells from snow crab and shrimp in Canada and India, respectively, the processing of these in China and India and the manufacture of chitosan in Europe and India. Primary data for chitin and chitosan production were obtained from the actual producers, whereas raw material acquisition as well as waste management activities were based on literature sources. The effects of indirect land use change (iLUC) were also included. Impact assessment was carried out at midpoint level by means of the recommended methods in the International Life Cycle Data (ILCD) handbook.

Results and discussion

In the Indian supply chain, the production of chemicals (HCl and NaOH) appears as an important hot spot. The use of shrimp shells as raw material affects the market for animal feed, resulting in a credit in many impact indicators, especially in water use. The use of protein waste as fertilizer is also an important source of greenhouse-gas and ammonia emissions. In the European supply chain, energy use is the key driver for environmental impacts, namely heat production based on coal in China and electricity production in China and Europe. The use of crab shells as raw material avoids the composting process they would be otherwise subject to, leading to a saving in composting emissions, especially ammonia. In the Indian supply chain, the effect of iLUC is relevant, whereas in the European one, it is negligible.

Conclusions

Even though we assessed two products from the same family, the results show that they have very different environmental profiles, reflecting their substantially different supply chains in terms of raw material (shrimp shells vs. crab shells), production locations (locally produced vs. a global supply chain involving three continents) and the different applications (general-purpose chitosan vs. chitosan for the medical sector).
  相似文献   
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998.

Background

Quality Improvement Programs (QIP) in cystic fibrosis (CF) care have emerged as strategies to reduce variability of care and of patient outcomes among centres facilitating the implementation of Best Practices in all centres. The US CF Foundation developed a Learning and Leadership Collaborative program which was transposed in France in 2011. Patient and parent involvement (P&PI) on the local quality teams (QTs) is one dimension of this complex intervention. The conditions and effects of this involvement needed to be evaluated.

Methods

In all settings, patients and parents were recruited by their centre care team. They were trained to QI method and tools and contributed their own expertise to improve the process of care. This involvement has been analyzed in the frame of the whole process evaluation. Observations and interviews conducted during the course of the first training year explored the motivations of the patients and parents to participate and the vision of the health care teams. A research study was carried out after three years with the patients/parents and the professionals to assess the French QIP’s effectiveness using a questionnaire to report their opinions on various components of the program, including their experience of P&PI. Responses were analyzed in view of identifying consensus and dissensus between the two groups.

Results

At the introduction of the program, P&PI was an opportunity for healthcare providers to reflect on their conceptions of these individuals both as patients and as healthcare system users. Curiosity about the teams’ functioning, the various center organizations and outcomes led patients to overcome their initial barriers to participation. Seventy-six people including 12 patients/parents from the 14 pilot centres responded to the questionnaire after 3 years. Consensus between professionals and patients/parents was high on most items characterizing the performance of the QIP, QT effectiveness and QT functioning. Patients, parents and professionals agreed on the main characteristics of care such as an optimized organization, multidisciplinary care and patient-centredness. Regarding the use of patient electronic records, the use of care guidelines or the organization of support in the patient community, responses were not consensual amongst patients/parents and a source of dissensus between the two groups. All agreed that the French QIP created good conditions for their involvement. In the end, both groups agreed that it was difficult to attribute the paternity of some changes specifically to any member in the team.

Discussion

Perspectives such as an educational framework to develop the skills and behaviors of professionals engaged in collaborative practice with patients and families and large patient experience surveys could be used to capture patients’ experience of care in the improvement work.

Conclusion

Success factors for patient/parent long-term involvement in QIPs have been identified. Answers to questions raised by the stakeholders about the feasibility, efficiency and usefulness of P&PI in this CF QIP could be given but new questions arose about the sustainability of continuous quality improvement over time.
  相似文献   
999.
Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their quantitative significance is still only loosely constrained. Although part of this uncertainty can be attributed to the difficulties in measuring highly variable fluxes, it is also the result of a lack of a clear accounting methodology, particularly about what constitutes new emissions and potential new sinks. In this paper, we review the main processes involved in the generation of GHG in reservoir systems and propose a simple approach to quantify the reservoir GHG footprint in terms of the net changes in GHG fluxes to the atmosphere induced by damming, that is, ‘what the atmosphere sees.’ The approach takes into account the pre-impoundment GHG balance of the landscape, the temporal evolution of reservoir GHG emission profile as well as the natural emissions that are displaced to or away from the reservoir site resulting from hydrological and other changes. It also clarifies the portion of the reservoir carbon burial that can potentially be considered an offset to GHG emissions.  相似文献   
1000.

Background

We recently showed that transient warming effects decreased the functional and adhesion properties of mesenchymal stromal cells (MSC) while post-thaw viability remained high. In an attempt to better predict functional impairment of cryopreserved MSC, we further analysed the correlation between viability, immunosuppressive activity and adhesion of cells exposed or not to warming events.

Methods

MSC prepared from six umbilical cords were frozen to ?130°C and immediately transferred in a dry ice container or exposed to room temperature for 2 to 10 min (warming events) prior to storage in liquid nitrogen. Viability, functionality (inhibition of T-cell proliferation), adhesion and expression of various integrins were evaluated.

Results

The monotonic loss of functional activity with time was proportional to the length of warming events to which MSC were subjected and correlated with the monotonic loss of adhesion capacity. In contrast, post-thaw viability assessment did not predict functional impairment. Interestingly, flow cytometry analyses revealed the emergence of a FSClow population present in the viable cell fraction of freshly thawed MSC, which displayed poor adhesion capacity and expressed low levels of integrin β5. The prevalence of this FSClow population increased with the length of warming events and correlated with impaired functional and adhesion properties.

Discussion

Our results reveal that loss of functional activity (4-day test) induced by transient warming events could be predicted by evaluating adhesion (2-hr test) or FSC profile (10-min test) of MSC immediately post-thaw. These observations could lead to the development of surrogate tests for rapidly assessing the functional quality of cryopreserved MSC.  相似文献   
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