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51.
52.
Heat Shock Proteins in Two Lines of Zea mays L. That Differ in Drought and Heat Resistance 总被引:2,自引:0,他引:2 下载免费PDF全文
Synthesis of heat shock proteins (HSPs) in the leaves of a drought- and heat-resistant (line ZPBL 1304), and a drought- and heat-sensitive (line ZPL 389) line of maize (Zea mays L.) was studied under two environmental stress treatments: (a) soil drying and high temperature and (b) high temperature. In the first treatment 13-day-old plants were exposed to 7-day soil drying followed by high temperature stress (45°C), and in the second treatment 20-day-old plants were exposed to high temperature stress (45°C). Second leaves were labeled with [35S]methionine. During the labeling period line ZPBL 1304 showed no signs of leaf dehydration under soil drying and high temperature stress conditions. In contrast, line ZPL 389 was dehydrated 23%, as determined by relative water content. Incorporation of [35S]methionine into protein was greater in the resistant than in the sensitive line in both treatments. The pattern of synthesis of HSPs in the two lines was similar in treatments 1 and 2. Both lines synthesized a high molecular mass set and a low molecular mass set of HSPs. Proteins from both sets from both lines of maize appeared similar to each other, with respect to the molecular mass. Heated plants of the drought- and heat-resistant line ZPBL 1304 synthesized a band of HSP(s) of approximately 45 kilodaltons which was not found in heated plants of the drought and heat sensitive line ZPL 389. This is the first report on qualitative intraspecific difference in the synthesis of HSPs in maize. 相似文献
53.
Glasnović M Bosnjak I Vcev A Soldo I Kosuta M Lenz B Glasnović-Horvatić E Soldo-Butković S Mićunović N 《Collegium antropologicum》2007,31(1):173-177
The aim of the research was to show our diagnostic and therapeutic experience with antiphospholipid syndrome (APS) in pregnant women. 36 pregnant women suspect on APS were included in the study: 32 with primary antiphospholipd syndrome (PAPS) and 4 with secondary antiphospholipid syndrome (SAPS). All pregnant women received low-molecular-weight-heparin (LMWH) and low dose aspirin (LDA) therapy. Control group represented 26 women with SAPS and previous bad reproductive anamnesis. Average pregnancy lasted 37.06 +/- 0.707 weeks. LMWH and LDA therapy was successful in 97.22%. Lupus anticoagulant (LA) was found to be more frequent in PAPS group (71.87%). Anticardiolipin antibodies (aCL) were found to be more frequent in SAPS (26.66%). For three patients (3.37%), PAPS was diagnosed due to a fact that they had positive antibeta2-glycoproteinl (antibeta-GP1). To make APS diagnosis, it is of great importance to search for all antiphospholipid antibodies. LMWH and low dose of acetylsalicylic acid should be the first choice therapy. 相似文献
54.
Fluorescent human RAD51 reveals multiple nucleation sites and filament segments tightly associated along a single DNA molecule 总被引:3,自引:0,他引:3
Modesti M Ristic D van der Heijden T Dekker C van Mameren J Peterman EJ Wuite GJ Kanaar R Wyman C 《Structure (London, England : 1993)》2007,15(5):599-609
The DNA strand-exchange reactions defining homologous recombination involve transient, nonuniform allosteric interactions between recombinase proteins and their DNA substrates. To study these mechanistic aspects of homologous recombination, we produced functional fluorescent human RAD51 recombinase and visualized recombinase interactions with single DNA molecules in both static and dynamic conditions. We observe that RAD51 nucleates filament formation at multiple sites on double-stranded DNA. This avid nucleation results in multiple RAD51 filament segments along a DNA molecule. Analysis of fluorescent filament patch size and filament kinks from scanning force microscopy (SFM) images indicate nucleation occurs minimally once every 500 bp. Filament segments did not rearrange along DNA, indicating tight association of the ATP-bound protein. The kinetics of filament disassembly was defined by activating ATP hydrolysis and following individual filaments in real time. 相似文献
55.
56.
Pavan J Stambuk N Curković T Konjevoda P Pavan-Jukić D Gotovac M Karaman K 《Collegium antropologicum》2005,29(1):315-319
We evaluated the effectiveness of latanoprost (Xalatan) monotherapy in primary open angle glaucoma (POAG). Latanoprost is a prostaglandin analogue, the pure 15(R) epimer of 13,14-dihydro-17-phenyl-18,19,20-trinor-PGF2alpha-isopropyl ester. As a prodrug it is being activated by enzymatic hydrolysis in the cornea after which it becomes active acid of latanoprost. Latanoprost is lowering the intraocular pressure (IOP) by increasing the uveoscleral outflow. In this study, latanoprost was used once daily as monotherapy what offers much better compliance for the patients than other combinations of drugs, preserving good IOP control. Based on the significant reduction of the IOP, measured on the day 60 of the trial (mean change in IOP was -5.1 mmHg, with 95% confidence interval in range from -5.6 to -4.5), it is concluded that use of latanoprost is advisable when calculating better IOP control, few side-effects and reductions in costs of potential surgical procedures. 相似文献
57.
This paper introduces a novel generic approach for classification problems with the objective of achieving maximum classification accuracy with minimum number of features selected. The method is illustrated with several case studies of gene expression data. Our approach integrates filter and wrapper gene selection methods with an added objective of selecting a small set of non-redundant genes that are most relevant for classification with the provision of bins for genes to be swapped in the search for their biological relevance. It is capable of selecting relatively few marker genes while giving comparable or better leave-one-out cross-validation accuracy when compared with gene ranking selection approaches. Additionally, gene profiles can be extracted from the evolving connectionist system, which provides a set of rules that can be further developed into expert systems. The approach uses an integration of Pearson correlation coefficient and signal-to-noise ratio methods with an adaptive evolving classifier applied through the leave-one-out method for validation. Datasets of gene expression from four case studies are used to illustrate the method. The results show the proposed approach leads to an improved feature selection process in terms of reducing the number of variables required and an increased in classification accuracy. 相似文献
58.
Kiebel GR Auberry KJ Jaitly N Clark DA Monroe ME Peterson ES Tolić N Anderson GA Smith RD 《Proteomics》2006,6(6):1783-1790
Advanced proteomic research efforts involving areas such as systems biology or biomarker discovery are enabled by the use of high level informatics tools that allow the effective analysis of large quantities of differing types of data originating from various studies. Performing such analyses on a large scale is not feasible without a computational platform that performs data processing and management tasks. Such a platform must be able to provide high-throughput operation while having sufficient flexibility to accommodate evolving data analysis tools and methodologies. The Proteomics Research Information Storage and Management system (PRISM) provides a platform that serves the needs of the accurate mass and time tag approach developed at Pacific Northwest National Laboratory. PRISM incorporates a diverse set of analysis tools and allows a wide range of operations to be incorporated by using a state machine that is accessible to independent, distributed computational nodes. The system has scaled well as data volume has increased over several years, while allowing adaptability for incorporating new and improved data analysis tools for more effective proteomics research. 相似文献
59.
During the past several decades there has been a substantial increase in the incidence of malignant melanoma worldwide. The highest incidences were reported in New Zealand and Australia. In Europe the northern countries generally have a higher incidence. The aim of this retrospective study was to provide the incidence and mortality for all patients with malignant melanoma diagnosed in Osijek-Baranya County, Eastern Croatia, during 2000-2008. In the past 30 years in the Republic of Croatia the incidence of melanoma increased by 337%. During the period of 2000-2006 in Osijek-Baranja County, the incidence of melanoma increased by 13%. The incidence of melanoma increases with age, but in past decades melanoma is more often diagnosed in people aged 25-40. The mortality between 2000 and 2008 increased by 18%. The incidence of melanoma generally increases equally in men and women. The most common localization of skin melanoma in males was trunk and in females the lower extremities. Presently, in Osijek-Baranya County melanoma is 15th on the list of malignant tumors and represent 2% of all malignant tumors. In New Zealand, Australia and European northern countries mortality is reduced, as result of earlier diagnosis and education of risk groups. Unfortunately, in Osijek-Baranya County, in a comparison with these countries, the mortality is higher although incidence is the same or lower. 相似文献
60.
Cicvarić T Bencević-Striehl H Juretić I Marinović M Grzalja N Ostrić M 《Collegium antropologicum》2010,34(Z2):199-204
Geriatric hip fractures (GHP) are the major problem in the geriatric traumatology and it is estimated that treatment of GHF will spend a large amount of health care resources. The aim of this retrospective study was to compare differences in incidence of operatively treated patients with GHF, type of treatment depending of the type of fracture, early postoperative mortality, length of stay and costs of used implants within a 10 years period. Surgically treated 2478 patients, older than 65 years with hip fractures were included in the study. Patients were grouped according to the type of fracture (femoral neck fracture or intertrochanteric femoral fracture) and used implant. Results showed increasing trend in GHF in our County in the last 10 years. There was a shifting trend in used implants, and new surgical techniques were used more commonly in the last few years. In observed period there were no significant changes in revision surgery and length of hospital stay. The mortality decreased, especially in males, but generally it was not in correlation with used implant. At the 10-years period increase in patients with GHF of 179% was followed with 4 time higher increase in implant prices. Present reimbursement in health care system does not calculate the difference of implant costs in hospital expenses, therefore proper usage of modern implants and careful planning in the treatment of GHF is necessary. 相似文献