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141.
The development of vaccines to prevent infectious diseases has been one of the most important contributions of biomedical sciences. Increasing understanding in biochemistry, molecular biology, molecular genetics and related fields have provided an opportunity for the development of new generation vaccines that are based on rational design approaches. This is possible because of proper understanding of the microbial-genetics, biochemistry, host-pathogen interaction and recent developments in molecular immunology. Another important improvement made in the quality of vaccine production is the incorporation of immunomodulators or adjuvants with modified delivery vehicles viz liposomes, Iscoms and microspheres apart from alum being used as a gold standard. This article reviews the art of vaccination from Jenner period to present day context highlighting all the developments made at each stage of the vaccine development. Various criteria have been discussed regarding the selection of epitopes that expand B & T cells, its linkage with other accessory cells of the immune system, means to overcome MHC linked immune unresponsiveness, enhanced antigen processing and presentations that specially induce either helper or cytotoxic or mucosal immune responses were critically discussed.  相似文献   
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This paper investigates whether performance in progressive assessment necessarily influences the outcome in the end-of-semester final examination using the experience of an introductory postgraduate statistics course at a large Australian university. The average score on progressive assessments was higher than that of the final examination. Students attaining a higher distinction (HD) at the progressive assessment had a 37% chance of securing the same grade in the final examination, while students securing just a pass grade at the progressive assessment had 54 percent chance of failure in the final examination. Multiple regression analysis revealed that students’ performance in progressive assessments had a significant positive impact on final examination, so has the impact of learning diary. Mid-semester tests based exclusively on multiple choice questions (MCQs), more weights in progressive assessment and class-size appeared to have significant negative impact on the performance in the final examination. Focus group discussions suggest that (a) the final examination under timed conditions; (b) competing demands on time for final examination in other courses due contemporaneously; and (c) weaker motivation to sustain the momentum due to pass or near pass based on progressive assessments were the main hurdles in achieving better performance in the final examination.  相似文献   
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Gallbladder cancer has a poor outcome because of its anatomy and location. Often, the diagnosis is made very late due to its silent course. Post-operated cases do respond to chemotherapy but the survival is counted in months and the quality of life is further hampered due to toxicity of drugs. Immunotherapy holds good promise in non-responding cancers treated by conventional chemotherapeutic agents. Among various therapies, dendritic cell therapy is growing at rapid pace due to its acceptable rationale. It has been utilized in treating successfully resected stage Ill (T2, N1, M0) gallbladder cancer in one of our patients. A 48 years old lady treated with this therapy is free of metastasis with ten doses of autologous dendritic cell vaccine constructed by utilizing resected tumor lysate antigen. She has received ten doses of therapy in 14 months of her treatment. This therapy has proven to be safe and without apparent side effects. The positive clinical response obtained supports that autologous dendritic cell-based immunotherapy is a promising therapeutic approach for refractory gallbladder cancers.  相似文献   
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Of 6634 registered industries in Pakistan, 1228 are considered to be highly polluting. The major industries include textile, pharmaceutical, chemicals (organic and inorganic), food industries, ceramics, steel, oil mills and leather tanning which spread all over four provinces, with the larger number located in Sindh and Punjab, with smaller number in North Western Frontier Province (NWFP) and Baluchistan. Hattar Industrial Estate extending over 700 acres located in Haripur district of NWFP is a new industrial estate, which has been developed with proper planning for management of industrial effluents. The major industries located in Hattar are ghee industry, chemical (sulfuric acid, synthetic fiber) industry, textile industry and pharmaceuticals industry. These industries, although developed with proper planning are discharging their effluents in the nearby natural drains and ulti- mately collected in a big drain near Wah. The farmers in the vicinity are using these effluents for growing vegetables and cereal crops due to shortage of water. In view of this discussion, there is a dire need to determine if these effluents are hazardous for soil and plant growth. So, effluents from different industries, sewage and normal tap water samples were collected and analysed for pH electrical conductivity (EC), total soluble salts (TSS), biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen, cations and anions and heavy metals. The effluents ofghee and textile industries are highly alkaline. EC and TSS loads of ghee and textile industries are also above the National Environmental Quality Standards (NEQS), Pakistan. All the effluents had residual sodium carbonates (RSCs), carbonates and bicarbonates in amounts that cannot be used for irrigation. Total toxic metals load in all the effluents is also above the limit i.e. 2,0 mg/L. Copper in effluents of textile and sewage, manganese in ghee industry effluents and iron contents in all the effluents were higher than NEQS. BOD and COD values of all the industries are also above the NEQS. On the whole, these effluents cannot be used for irrigation without proper treatment otherwise that may cause toxicity to soil, plants and animals as well add to the problems of salinity and sododicity. Similarly, these effluents cannot be used for fish farming.  相似文献   
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Brigham Young University's Harold B. Lee Library conducted a time-task cost study to compare the cost and processing time of shelf-ready books to non-shelf-ready books to determine if it could better use its human resources and if it should expand the use of shelf-ready to include its approval books. The results showed that shelf-ready was, on average, 5.7% cheaper, took 47% less processing time, and arrived on the shelves 33 sooner than books processed in-house. Based on the results of the study, the library moved its approval books to the shelf-ready program and was able to reallocate catalogers tasks.  相似文献   
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The study is focused on users' opinion as regards the adequacy of library collection and analyzes the level of users' satisfaction about library collection, organization, facilities and services both traditional as well as, IT enabled services. A well structured questionnaire was administered to faculty members, research scholars and students of the AMU to collect data regarding the adequacy of library collection and analyze the level of users' satisfaction. The survey reveals that the library collection in the AMU library is adequate enough for their users. AMU library users were also satisfied with the existing infrastructure of library and organization of their collections. The researcher observed that the overall satisfaction levels of the users regarding the AMU library is good.  相似文献   
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Organoids are biological systems grown in vitro and are observed to self-organize into 3D cellular tissues of specific organs. Brain organoids have emerged as valuable models for the study of human brain development in health and disease. Researchers are now in need of improved culturing and imaging tools to capture the in vitro dynamics of development processes in the brain. Here, we describe the design of a microfluidic chip and bioreactor, to enable in situ tracking and imaging of brain organoids on-chip. The low-cost 3D printed microfluidic bioreactor supports organoid growth and provides an optimal imaging chamber for live-organoid imaging, with drug delivery support. This fully isolated design of a live-cell imaging and culturing platform enables long-term live-imaging of the intact live brain organoids as it grows. We can thus analyze their self-organization in a controlled environment with high temporal and spatial resolution.  相似文献   
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