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1.
The complexes between the Fab fragments of two monoclonal anti-lysozyme antibodies, Fab10.6.6 (high affinity) and D44.2 (lower affinity), and their specific antigen, hen egg-white lysozyme, have been crystallized. The antibodies recognize an antigenic determinant including Arg68, but differ significantly in their association constants for the antigen. Two crystalline forms were obtained for the complex with FabF10.6.6, the higher affinity antibody. One of them is monoclinic, space group P21, with unit cell dimensions a = 145.6 A, b = 78.1 A, c = 63.1 A, beta = 89.05 degrees, consistent with the presence of two molecules of the complex in the asymmetric unit. These crystals diffract X-rays beyond 3 A making this form suitable for high-resolution X-ray diffraction studies. The second form crystallizes in the triclinic space group P1, with unit cell dimensions a = 134.0 A, b = 144.7 A, c = 98.6 A, alpha = 90.30 degrees, beta = 97.1 degrees, gamma = 90.20 degrees, consistent with the presence of 10 to 12 molecules of the complex in the unit cell. These crystals do not diffract X-rays beyond 5 A resolution. The antigen-antibody complex between FabD44.2, the lower affinity antibody, and hen egg-white lysozyme crystallizes in space group P2(1)2(1)2(1), with unit cell dimensions a = 99.7 A, b = 167.3 A, c = 84.7 A, consistent with the presence of two molecules of the complex in the asymmetric unit. These crystals diffract X-rays beyond 2.5 A resolution.  相似文献   
2.
Five antibodies, 2D.1 (pan-leukocyte), AE-1,3 (anti-keratin), B72.3 (anti-carcinoma), ME 1-14 (alpha-chondroitin sulfate proteoglycan) and polyclonal S-100 protein (P-S100), were tested to determine if this panel could be used immunocytochemically to differentiate melanoma from nonmelanoma. A total of 161 cases were evaluated: 145 fine needle aspirates of various body sites and 16 effusions, consisting of 52 melanomas, 41 adenocarcinomas, 11 squamous cell carcinomas, 14 undifferentiated carcinomas, 8 small cell carcinomas, 8 miscellaneous carcinomas, 8 primary central nervous system (CNS) tumors, 7 lymphomas/leukemias, 4 sarcomas and 8 benign effusions. The 52 melanomas were stained by ME 1-14 (in 31 cases) and by P-S100 (in 39 cases), but not by B72.3, AE-1,3 or 2D.1. The 82 carcinomas reacted with P-S100 (in 25 cases), B72.3 (in 37 cases), AE-1,3 (in 68 cases) and 2D.1 (in 1 case), but not with ME 1-14. Lymphomas were stained only by 2D.1 (5 of 7 cases). The eight primary CNS tumors reacted solely with ME1-14 (in 3 cases) and P-S100 (in 3 cases). The eight benign effusions exhibited staining by ME 1-14 (in 1 case), P-S100 (in 1 case), AE-1,3 (in 3 cases) and 2D.1 (in 8 cases), but not by B72.3. Thirty-six cases (including 11 melanomas) failed to stain with any antibody. In summary, 41 of 52 melanomas and 4 of 8 CNS tumors stained with ME1-14, P-S100 or both and were negative for B72.3, AE-1,3 and 2D.1. Only 2 of 101 other nonmelanomas exhibited this pattern. Thus, this panel distinguishes melanoma from other neoplastic and nonneoplastic processes in the majority of cases.  相似文献   
3.
Microorganisms strongly influence and are required to generate the selective substrate that provides nutrients and support for fungal growth, and ultimately to induce mushroom fructification under controlled environmental conditions. In this work, the fungal and bacterial microbiota living in the different substrates employed in a commercial crop (compost phase I, II and III, flush 1 and 2, and casing material on day 1, 6 and 8 after compost casing and during flush 1 and 2) have been characterized along the different stages of cultivation by metataxonomic analysis (16S rRNA and ITS2), analysis of phospholipid fatty acid content (PLFAs) and RT-qPCR. Additionally, laccase activity and the content of lignin and complex carbohydrates in compost and casing have been quantified. The bacterial diversity in compost and casing increased throughout the crop cycle boosted by the connection of both substrates. As reflected by the PLFAs, the total living bacterial biomass appears to be negatively correlated with the mycelium of the crop. Agaricus bisporus was the dominant fungal species in colonized substrates, displacing the pre-eminent Ascomycota, accompanied by a sustained increase in laccase activity, which is considered to be a major product of protein synthesis during the mycelial growth of champignon. From phase II onwards, the metabolic machinery of the fungal crop degrades lignin and carbohydrates in compost, while these components are hardly degraded in casing, which reflects the minor role of the casing for nourishing the crop. The techniques employed in this study provide a holistic and detailed characterization of the changing microbial composition in commercial champignon substrates. The knowledge generated will contribute to improve compost formulations (selection of base materials) and accelerate compost production, for instance, through biotechnological interventions in the form of tailored biostimulants and to design environmentally sustainable bio-based casing materials.  相似文献   
4.

Introduction  

Intraarticular administration of autologous conditioned serum (ACS) recently demonstrated some clinical effectiveness in treatment of osteoarthritis (OA). The current study aims to evaluate the in vitro effects of ACS on cartilage proteoglycan (PG) metabolism, its composition and the effects on synovial fluid (SF) cytokine levels following intraarticular ACS administration.  相似文献   
5.
The invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to identify the primary abiotic drivers behind abundance patterns of T. granifera, by comparing the current abundance of the snail in three different regions, and at three depths, of the highly modified Nseleni River in KwaZulu-Natal, South Africa. Tarebia granifera was well established throughout the Nseleni River system, with an overall preference for shallow waters and seasonal temporal patterns of abundance. Although it is uncertain what the ecological impacts of the snail in this system are, its high abundances suggest that it should be controlled where possible and prevented from invading other systems in the region.  相似文献   
6.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected.  相似文献   
7.
Water hyacinth Eichhornia crassipes is considered the most damaging aquatic weed in the world. However, few studies have quantified the impact of this weed economically and ecologically, and even fewer studies have quantified the benefits of its control. This paper focuses on water loss saving as the benefit derived from biological control of this plant between 1990 and 2013 at New Year’s Dam, Alicedale, Eastern Cape, South Africa. Estimates of water loss due to evapotranspiration from water hyacinth vary significantly; therefore, the study used three different rates, high, medium and low. A conservative raw agriculture value of R 0.26 per m3 was used to calculate the benefits derived by the water saved. The present benefit and cost values were determined using 10% and 5% discount rates. The benefit/cost ratio at the low evapotranspiration rate was less than one, implying that biological control was not economically viable but, at the higher evapotranspiration rates, the return justified the costs of biological control. However, at the marginal value product of water, the inclusion of the costs of damage to infrastructure, or the adverse effects of water hyacinth on biodiversity, would justify the use of biological control, even at the low transpiration rate.  相似文献   
8.
From 2006 through 2014, we conducted seroepidemiological surveys on non-human primates and sloths to investigate the possible circulation of arboviruses in Bahia Atlantic Forest, Brazil. We collected a total of 196 samples from 103 Leontopithecus chrysomelas, 7 Sapajus xanthosternos, 22 Bradypus torquatus and 7 Bradypus variegatus. Serum samples were tested using neutralization test and hemagglutination inhibition test to detect total antibodies against 26 different arboviruses. The overall prevalence of arboviruses was 36.6% (51/139), with the genus Flavivirus having the highest prevalence (33.1%; 46/139), followed by Phlebovirus (5.0%; 7/139), Orthobunyavirus (4.3%; 6/139) and Alphavirus (0.7%; 1/139). Monotypic reactions suggest that the wild animals were exposed naturally to at least twelve arboviruses. Added results from the neutralization test, animals were exposed to thirteen arboviruses. Most of these viruses are maintained in transmission cycles independent of human hosts, although antibodies against dengue virus serotypes 1, 2 and 3 were found in this study. To our knowledge, this is the first study reporting exposure to arboviruses in L. chrysomelas, S. xanthosternos and B. torquatus. Our results also highlight that the Southern Bahia Atlantic Forest has a variety of vertebrate hosts and potential vectors, which may support the emergence or re-emergence of arboviruses, including those pathogenic to humans.  相似文献   
9.
10.
The cytologic evaluation of poorly differentiated tumors frequently poses a diagnostic dilemma as to the tissue of origin. To assess the diagnostic utility of monoclonal antibodies (MAbs) in these situations, we applied a panel of three highly purified MAbs specific for tumor-associated ganglioside epitopes to a diverse series of cytologic specimens. The panel was composed of DMAb-3, reactive with the epitope GalNAc beta 1-4 (NeuAc alpha 2-3)Gal- of GM2; DMAb-7, reactive with the epitope (NeuAc alpha 2-8NeuAc alpha 2-3)Gal beta 1-4(Glc or GlcNAc)- of GD3 and 3'8'-LD1; and DMAb-20, reactive with the epitope GalNAc beta 1-4(NeuAc alpha 2-8NeuAc alpha 2-3)Gal- of GD2. The cytologic material consisted of air-dried Cytospin preparations prepared predominantly from fine needle aspirates and stained with the ABC immunohistochemical method. Positive reactivity was recognized when greater than 5% of tumor cells stained with the antibody; lesser reactivity was called negative. DMAb-3 stained 9/14 (64%) glial tumors, 4/13 (31%) nonglial central nervous system tumors, 1/21 (5%) melanomas, 7/38 (18%) non-small cell carcinomas (NSCC), 1/15 (7%) small cell carcinomas (SCC), 0/9 (0%) lymphomas/leukemias, 2/10 (20%) sarcomas, 1/7 (14%) miscellaneous tumors and 2/2 (100%) reactive fluids. DMAb-7 recognized 14/14 (100%) glial tumors, 9/13 (69%) non-glial central nervous system tumors, 19/22 (86%) melanomas, 19/43 (44%) NSCC, 5/15 (33%) SCC, 2/9 (22%) lymphomas/leukemias, 6/10 (60%) sarcomas, 1/7 (14%) miscellaneous tumors and 4/4 (100%) reactive fluids. DMAb-20 stained 6/14 (43%) glial tumors, 2/13 (15%) nonglial central nervous system tumors, 1/21 (5%) melanomas, 4/38 (10%) NSCC, 0/15 (0%) SCC, 0/9 (0%) lymphomas/leukemias, 1/10 (10%) sarcomas, 1/7 (14%) miscellaneous tumors and 1/3 (33%) reactive fluids. The GD3-reactive DMAb-7 recognized a large portion of many tumor types and thus is not diagnostically useful alone. DMAb-3 and DMAb-20 were more selective and showed the strongest reactivity for glial tumors and minimal reactivity for melanomas, small cell carcinomas, and lymphomas or leukemias. DMAb-3 and DMAb-20 may be useful as components of a larger panel of MAbs in distinguishing between poorly differentiated tumors in samples derived from the central nervous system.  相似文献   
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