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排序方式: 共有331条查询结果,搜索用时 31 毫秒
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The Flora of the Perivaginal Area: The Normal Flora and the Effect of a Deodorant Spray 总被引:1,自引:1,他引:0
Susan Crowley Catherine T. Murphy Pamela M. White W. C. Noble Elizabeth R. M. Rowell D. Bluett 《Journal of applied microbiology》1974,37(3):385-392
S ummary . The microbial flora of the thigh adjacent to the vaginal labia and of the mucosal surface of the labia has been examined quantitatively and qualitatively in students from Colleges of Education and a University, and in persons attending a Consultant Gynaecologist for non-suppurative conditions. In the 2 student populations, members of the Micrococcaceae and diphtheroids were the most common organisms but all populations yielded many organisms of gut origin. Differences between the populations may relate to social and hygienic conditions and should make us wary of direct comparisons with other, different populations. The effect of intimate hygiene deodorants containing 0.01% or 0.02% of chlorhexidine was compared with a base spray containing no antibacterial agent. No significant effect of these sprays on the microbial flora could be demonstrated. 相似文献
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Anett Richter Will Osborne Sarah Hnatiuk Alison Rowell 《Journal of Insect Conservation》2013,17(6):1093-1104
The conservation and management of endangered species requires an adequate understanding of their biology and ecology. Although there has been an increasing appreciation in Australia of the need for greater efforts to conserve insects, there is only limited information available that can be used to underpin conservation efforts. The endangered golden sun moth, Synemon plana (Lepidoptera: Castniidae) is a flagship species endemic to natural temperate grassland in south-eastern Australia. Most populations of this species are at considerable risk from habitat loss, weed invasion and inadequate management. Despite the considerable knowledge that exists about the species biology and ecology, efforts to improve the species conservation status are hampered because there are still critical gaps in our understanding of the species’ natural history. In particular, the ecology of the larvae is not known. Our study examined the abundance, population structure and reproductive biology of the moths in a broad sample of both natural temperate and exotic grassland remnants in and near Canberra in the Australian Capital Territory (ACT) in south-eastern Australia. The results fill critical gaps in the knowledge needed to achieve effective conservation management. From our findings, it is clear that the species inhabits grasslands dominated by a mixture of native wallaby grasses (Rytidosperma spp. (formerly Austrodanthonia)) and spear grasses (Austrostipa spp.). In contrast to earlier suggestions that S. plana is entirely confined to natural temperate grassland, mature and immature life stages of the species were also present in grasslands comprised entirely of the exotic Chilean needlegrass (Nassella neesiana). Most of the S. plana populations surveyed in the ACT were characterised by low relative abundance with only very few large populations being recorded. The conservation of exotic grasslands as substitute habitat for S. plana is discussed and suggestions regarding future monitoring and research of the species are provided. 相似文献
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Neylen Del Toro Ana Fernandez-Ruiz Lian Mignacca Paloma Kalegari Marie-Camille Rowell Sebastian Igelmann 《Cell cycle (Georgetown, Tex.)》2019,18(6-7):759-770
Senescence is a tumor suppressor program characterized by a stable growth arrest while maintaining cell viability. Senescence-associated ribogenesis defects (SARD) have been shown to regulate senescence through the ability of the ribosomal protein S14 (RPS14 or uS11) to bind and inhibit the cyclin-dependent kinase 4 (CDK4). Here we report another ribosomal protein that binds and inhibits CDK4 in senescent cells: L22 (RPL22 or eL22). Enforcing the expression of RPL22/eL22 is sufficient to induce an RB and p53-dependent cellular senescent phenotype in human fibroblasts. Mechanistically, RPL22/eL22 can interact with and inhibit CDK4-Cyclin D1 to decrease RB phosphorylation both in vitro and in cells. Briefly, we show that ribosome-free RPL22/eL22 causes a cell cycle arrest which could be relevant during situations of nucleolar stress such as cellular senescence or the response to cancer chemotherapy. 相似文献
27.
Nguyen T. Hien Nigel W. Kerby Gordon C. Machray Peter Rowell William D.P. Stewart 《FEMS microbiology letters》1988,56(3):337-341
Abstract The nucleoside analogue ganciclovir has clinical efficacy in the treatment of serious infections with human cytomegalovirus (CMV) in AIDS patients. The mechanism of action of the drug against CMV is different from that described for herpes simplex viruses (HSVs) as the crucial formation of the monophosphate derivative appears to be carried out by cellular rather than virus-coded enzymes. Adenovirus infections also induce the expression of cellular genes including kinase activity and a novel DNA polymerase and the results reported here show that these viruses are sensitive to ganciclovir. The 50% effective dose (ED50 ) range for known serotypes and one clinical isolate was 4.5−33 μM. By comparison with the sensitivity of CMV in vitro and the known clinical response of infections with this virus to ganciclovir, our results suggest that this drug or its analogous may form the basis of chemotherapy for adenovirus infections. 相似文献
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As a step towards developing a biosensor which can detect airborne protease droplets, a biosensor which had previously been developed to detect protease in solution is shown to be capable of detecting different concentrations of protease in liquid films on the sensor surface in air. The biosensor measured impedance change due to proteolytic digestion of its gelatin coating. In saturated air there was a rise in impedance, with a loss in weight of the gelatin, in proportion to collagenase concentration. The addition of glycerol to the gelatin caused a lower impedance response and smaller loss in weight. A critical thickness of the gelatin layer prior to a more rapid change in the rate of impedance was noted, with and without the addition of glycerol. In low air humidity (40%), with gelatin, all collagenase concentrations produced a very similar rapid increase in impedance. However, with glycerol-enhanced gelatin, there was a clear distinction between the extent of impedance change with different collagenase concentrations. The application of these findings for use in the field of bioaerosol sampling is discussed. 相似文献
29.
Urvater JA McAdam SN Loehrke JH Allen TM Moran JL Rowell TJ Rojo S López de Castro JA Taurog JD Watkins DI 《Immunogenetics》2000,51(4-5):314-325
The human major histocompatibility complex (MHC) class I gene, HLA-B27, is a strong risk factor for susceptibility to a group of disorders termed spondyloarthropathies. Rodents that express HLA-B27 develop spondyloarthropathies, implicating HLA-B27 in the etiology of these disorders. To determine whether an HLA-B27-like molecule was associated with spondyloarthropathies
in nonhuman primates, we analyzed the MHC class I cDNAs expressed in a cohort of rhesus macaques that developed reactive arthritis
after an outbreak of shigellosis. We identified several cDNAs with only limited sequence similarity to HLA-B27. Interestingly, one of these MHC molecules had a B pocket identical to that of HLA-B39. Pool sequencing of radiolabeled peptides
bound by this molecule demonstrated that, like HLA-B27 and HLA-B39, it could bind peptides with arginine at the second position.
However, extensive analysis of the MHC class I molecules in this cohort revealed no statistically significant association
between any particular MHC class I allele and susceptibility to reactive arthritis. Furthermore, none of the rhesus MHC class I
molecules bore a strong resemblance to HLA-B27, indicating that reactive arthritis can develop in this animal model in the
absence of an HLA-B27-like molecule. Surprisingly, there was a statistically significant association between the rhesus macaque
MHC A locus allele, Mamu-A*12, and the absence of reactive arthritis following Shigella infection.
Received: 26 July 1999 / Revised: 28 December 1999 相似文献
30.
A key transition in the evolution of the insect suborder Caelifera (Orthoptera; Insecta) was from predominantly non-angiosperm-feeding basal lineages to the modern acridomorph fauna (grasshoppers and related insects). However, because of conflicts in the distribution of several complex morphological characters, the relationships of the presumed intermediates, and in particular of the superfamily Pneumoroidea, are presently unclear. We undertook a phylogenetic study of representatives of all of the transitional acridomorph families using mitochondrial and nuclear DNA sequences. No support for pneumoroid monophyly was obtained from nonparametric bootstrap analysis. Furthermore, adopting a maximum-likelihood approach, specific hypotheses of relationships within the Pneumoroidea were firmly rejected using parametric bootstrapping and Kishino-Hasegawa tests. The results indicate that the Pneumoroidea are at best a grade. This distinction implies that the evolution of the proposed pneumoroid synapomorphies, femoro-abdominal stridulation and simple male genital structure, might previously have been misinterpreted as cases of single character gains or losses within lineages. Reconstructions of character states for the femoro-abdominal stridulation indicate that, in fact, multiple losses or gains are equally likely. An important implication of our findings is that, in grasshoppers, auditory tympana may have evolved before stridulation, supporting the argument that the original function of tympana may have been related not to conspecific communication but to predator detection. Overall, the results of this study emphasize the high information content of these minor groups (in this case, the four intermediate families under consideration contain only 0.2% of extant orthopteran species diversity). Our analyses also demonstrate the advantages of model-based methods in analyzing systematic problems and, in particular, of the importance of testing specific phylogenetic hypotheses when a priori support for groupings (e.g., from nonparametric bootstrapping) is marginal. 相似文献