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31.
Katharine N. Savage Kathy Burek-Huntington Sadie K. Wright Anna L. Bryan Gay Sheffield Marc Webber Raphaela Stimmelmayr Pam Tuomi Martha A. Delaney William Walker 《Marine Mammal Science》2021,37(3):843-869
Presented here is the first comprehensive and updated compilation of history, distribution, and findings of Stejneger's beaked whales (Mesoplodon stejnegeri) in Alaska. Stejneger's beaked whales are a poorly understood, elusive, deep-diving cetacean species found in the North Pacific Ocean. Since Stejneger's beaked whale strandings data in Alaska through 1994 were last published, 35 additional strandings have been documented. Twenty-seven animals stranded in the Aleutian Islands, seven stranded in Southcentral Alaska, and one animal stranded on St. Lawrence Island. Twenty-two carcasses were necropsied, but only four were fresh. Seventeen of the 22 died during mass stranding events and cause of death could not be definitively determined. Barotrauma was suspected in three cases and infectious disease possibly complicated by barotrauma occurred in two cases. We documented an expansion of strandings into the northern Bering Sea, characterized a sex bias, examined stomach contents that included macroplastic, and identified parasites not previously associated with Stejneger's beaked whales. Also included are data on the largest known mass stranding of Stejneger's beaked whales, which occurred on Adak Island in 2018. The history, distribution, and findings presented here are central to further our understanding of this species. 相似文献
32.
Pam Harrison 《CMAJ》1985,132(12):1434-1435
33.
William A Cafruny Richard G Duman Grace HW Wong Suleman Said Pam Ward-Demo Raymond RR Rowland Eric A Nelson 《Virology journal》2006,3(1):1-17
Background
Porcine reproductive and respiratory syndrome virus (PRRSV) is the etiologic agent of PRRS, causing widespread chronic infections which are largely uncontrolled by currently available vaccines or other antiviral measures. Cultured monkey kidney (MARC-145) cells provide an important tool for the study of PRRSV replication. For the present study, flow cytometric and fluorescence antibody (FA) analyses of PRRSV infection of cultured MARC-145 cells were carried out in experiments designed to clarify viral dynamics and the mechanism of viral spread. The roles of viral permissiveness and the cytoskeleton in PRRSV infection and transmission were examined in conjunction with antiviral and cytotoxic drugs.Results
Flow cytometric and FA analyses of PRRSV antigen expression revealed distinct primary and secondary phases of MARC-145 cell infection. PRRSV antigen was randomly expressed in a few percent of cells during the primary phase of infection (up to about 20–22 h p.i.), but the logarithmic infection phase (days 2–3 p.i.), was characterized by secondary spread to clusters of infected cells. The formation of secondary clusters of PRRSV-infected cells preceded the development of CPE in MARC-145 cells, and both primary and secondary PRRSV infection were inhibited by colchicine and cytochalasin D, demonstrating a critical role of the cytoskeleton in viral permissiveness as well as cell-to-cell transmission from a subpopulation of cells permissive for free virus to secondary targets. Cellular expression of actin also appeared to correlate with PRRSV resistance, suggesting a second role of the actin cytoskeleton as a potential barrier to cell-to-cell transmission. PRRSV infection and cell-to-cell transmission were efficiently suppressed by interferon-γ (IFN-γ), as well as the more-potent experimental antiviral agent AK-2.Conclusion
The results demonstrate two distinct mechanisms of PRRSV infection: primary infection of a relatively small subpopulation of innately PRRSV-permissive cells, and secondary cell-to-cell transmission to contiguous cells which appear non-permissive to free virus. The results also indicate that an intact cytoskeleton is critical for PRRSV infection, and that viral permissiveness is a highly efficient drug target to control PRRSV infection. The data from this experimental system have important implications for the mechanisms of PRRSV persistence and pathology, as well as for a better understanding of arterivirus regulation. 相似文献34.
A Hydrophobin of the chestnut blight fungus, Cryphonectria parasitica, is required for stromal pustule eruption 下载免费PDF全文
Hydrophobins are abundant small hydrophobic proteins that are present on the surfaces of many filamentous fungi. The chestnut blight pathogen Cryphonectria parasitica was shown to produce a class II hydrophobin, cryparin. Cryparin is the most abundant protein produced by this fungus when grown in liquid culture. When the fungus is growing on chestnut trees, cryparin is found only in the fungal fruiting body walls. Deletion of the gene encoding cryparin resulted in a culture phenotype typical of hydrophobin deletion mutants of other fungi, i.e., easily wettable (nonhydrophobic) hyphae. When grown on the natural substrate of the fungus, however, cryparin-null mutation strains were unable to normally produce its fungal fruiting bodies. Although the stromal pustules showed normal development initially, they were unable to erupt through the bark of the tree. The hydrophobin cryparin thus plays an essential role in the fitness of this important plant pathogen by facilitating the eruption of the fungal fruiting bodies through the bark of its host tree. 相似文献
35.
Marina García-Llorente Paula A. Harrison Pam Berry Ignacio Palomo Erik Gómez-Baggethun Irene Iniesta-Arandia Carlos Montes David García del Amo Berta Martín-López 《Biodiversity and Conservation》2018,27(7):1575-1597
Biodiversity conservation strategies that overlook the interests of local people are prone to create conflicts. The ecosystem service approach holds potential for more comprehensively integrating the social dimension into decision-making in protected areas, but its implementation in conservation policies is still in its infancy. This research assesses the extent to which ecosystem services have been implemented in conservation strategies in protected areas. The study was conducted in two outstanding Spanish protected areas, covering a wetland (Doñana Natural and National Parks) and a Mediterranean mountain system (Sierra Nevada Natural and National Parks). Data were collected from deliberative workshops with managers and researchers, face-to-face surveys with users and a review of management plans. We found that, beyond intrinsic values of ecosystems and biodiversity, these areas provide multiple ecosystem services that deserve further attention to ensure their sustained delivery. Our research shows that environmental managers and researchers have different perceptions and priorities regarding ecosystem services management compared with ecosystem service users. Environmental managers and researchers in both protected areas perceived that human-nature relationships and ecosystem services are already widely included in management plans, if often not explicitly. We found that different ecosystem service categories receive uneven attention in management plans. These contained measures to manage provisioning and cultural services whereas measures for managing regulating services were perceived to be largely absent. We conclude by summarizing insights on how the ecosystem service approach may enhance the consideration of social interests in the management of management protected areas. 相似文献
36.
M Smith S Smalley R Cantor M Pandolfo M I Gomez R Baumann P Flodman K Yoshiyama Y Nakamura C Julier 《Genomics》1990,6(1):105-114
Tuberous sclerosis (TSC) is a dominantly inherited disorder characterized by hamartomas and hamartias in one or more organs, most often in skin, brain, and kidneys. Analysis of the basic genetic defect in tuberous sclerosis would be greatly expedited by definitive determination of the chromosomal location of the TSC gene or genes. We have carried out genetic linkage studies in 15 TSC families, using 34 polymorphic markers including protein markers and DNA markers. Pairwise lod scores were calculated using LIPED, and multipoint analyses were carried out using MENDEL. In the pairwise linkage analysis, using a penetrance value of 90%, a significant positive lod score was obtained with MCT128.1 (D11S144), 11q22-11q23, Zmax 3.26 at theta = 0.08. The tyrosinase probe TYR (11q14-11q22) gave a maximum lod score of 2.88 at theta = 0. In the multipoint analyses the most likely order is (TYR,TSC)-MCT128.1-HHH172. Homogeneity analysis was carried out using the USERM9 subprogram of MENDEL, which conducts the admixture test of C. Smith (1963, Ann. Hum. Genet. 27: 175-182). This test provided no evidence for genetic heterogeneity (that is, non-11-linked families) in this data set. 相似文献
37.
38.
Beswick P Charrier N Clarke B Demont E Dingwall C Dunsdon R Faller A Gleave R Hawkins J Hussain I Johnson CN MacPherson D Maile G Matico R Milner P Mosley J Naylor A O'Brien A Redshaw S Riddell D Rowland P Skidmore J Soleil V Smith KJ Stanway S Stemp G Stuart A Sweitzer S Theobald P Vesey D Walter DS Ward J Wayne G 《Bioorganic & medicinal chemistry letters》2008,18(3):1022-1026
This article is focusing on further optimization of previously described hydroxy ethylamine (HEA) BACE-1 inhibitors obtained from a focused library with the support of X-ray crystallography. Optimization of the non-prime side of our inhibitors and introduction of a 6-membered sultam substituent binding to Asn-294 as well as a fluorine in the C-2 position led to derivatives with nanomolar potency in cell-based assays. 相似文献
39.
A. Brent Richards Sarah Ward Debora A. Rothmond Pam L. Noble James T. Winslow 《Hormones and behavior》2009,56(1):140-148
Social behavior changes dramatically during primate adolescence. However, the extent to which testosterone and other gonadal hormones are necessary for adolescent social behavioral development is unknown. In this study, we determined that gonadectomy significantly impairs social dominance in naturalistic settings and changes reactions to social stimuli in experimental settings. Rhesus macaques were castrated (n = 6) or sham operated (n = 6) at age 2.4 years, group-housed for 2 years, and ethograms were collected weekly. During adolescence the gonadally intact monkeys displayed a decrease in subordinate behaviors and an increase in dominant behaviors, which ultimately related to a rise in social status and rank in the dominance hierarchy. We measured monkey's reactions to emotional faces (fear, threat, neutral) of conspecifics of three ages (adult, peer, infant). Intact monkeys were faster to retrieve a treat in front of a threatening or infant face, while castrated monkeys did not show a differential response to different emotional faces or ages. No group difference in reaction to an innate fear-eliciting object (snake) was found. Approach and proximity responses to familiar vs unfamiliar conspecifics were tested, and intact monkeys spent more time proximal to a novel conspecific as compared to castrates who tended to spend more time with a familiar conspecific. No group differences in time spent with novel or familiar objects were found. Thus, gonadectomy resulted in the emergence of significantly different responses to social stimuli, but not non-social stimuli. Our work suggests that intact gonads, which are needed to produce adolescent increases in circulating testosterone, impact social behavior during adolescences in primates. 相似文献
40.
Marylène Fortin Hélène D'Anjou Marie-ève Higgins Jasmine Gougeon Paméla Aubé Kamel Moktefi Sonia Mouissi Serge Séguin Rosanne Séguin Paolo M Renzi Luc Paquet Nicolay Ferrari 《Respiratory research》2009,10(1):39