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101.
We addressed the phylogeny of cockroaches using DNA sequence data from a broad taxon sample of Dictyoptera and other non‐endopterygotan insect orders. We paid special attention to several taxa in which relationships are controversial, or where no molecular evidence has been used previously: Nocticolidae, a family of small, often cave‐dwelling cockroaches, has been suggested to be the sister group of the predaceous Mantodea or of the cockroach family Polyphagidae; Lamproblatta, traditionally placed in Blattidae, has recently been given family status and placed as sister to Polyphagidae; and Saltoblattella montistabularis Bohn, Picker, Klass & Colville, a jumping cockroach, which has not yet been included in any phylogenetic studies. We used mitochondrial (COI + COII and 16S) and nuclear (18S and 28S) genes, and analysed the data using Bayesian inference (BI) and maximum likelihood (ML). Nocticolidae was recovered as sister to Polyphagidae. Lamproblatta was recovered as sister to Blattidae, consistent with the traditional placement (not based on phylogenetic analysis). However, because of the limited support for this relationship and conflict with earlier morphology‐based phylogenetic hypotheses, we retain Lamproblattidae. S. montistabularis was consistently placed as sister to Ectobius sylvestris Poda (Blaberoidea: Ectobinae), indicating that the saltatorial hindlegs of this genus are a relatively recent adaptation. Isoptera was placed within Blattodea as sister to Cryptocercidae. Nocticolidae + Polyphagidae was sister to Isoptera + Cryptocercidae, and Blaberoidea was sister to the remaining Blattodea.  相似文献   
102.
The use of structured psychiatric interviews performed by non-clinicians is frequent for research purposes and is becoming increasingly common in clini-cal practice. The validity of such interviews has rarely been evaluated empirically. In this study of a sample of 100 diagnostically heterogeneous, first-admitted inpatients, the results of an assessment with the Structured Clinical Interview for DSM-IV (SCID), yielding a DSM-IV diagnosis and performed by a trained non-clinician, were compared with a consensus lifetime best diagnostic estimate (DSM-IV) by two experienced research clinicians, based on multiple sources of information, which included videotaped comprehensive semi-structured narrative interviews. The overall kappa agreement was 0.18. The sensitivity and specificity for the diagnosis of schizophrenia by SCID were 19% and 100%, respectively. It is concluded that structured interviews performed by non-clinicians are not recommendable for clinical work and should only be used in research with certain precautions. It is suggested that a revival of systematic theoretical and practical training in psychopathology is an obvious way forward in order to improve the validity and therapeutic utility of psychiatric diagnosis.  相似文献   
103.
Cell wall activities which are related to the final stages oflignin biosynthesis, that is the generation of hydrogen peroxideand peroxidase activity, were investigated using biochemicaland histochemical methods. Peroxidases involved in both reactionsappeared to be restricted to lignifying tissues. Isolated cellwalls exhibited a very high affinity for syringaldazine. Cellwalls were able, in vitro as well as in vivo, to oxidize guaiacolin the absence of H2O2 when NADH was present in the incubationmedium together with p-coumarate and MnCl2 as cofactors. Theorigin of the NADH used to form H2O2 is discussed. Key words: Lignin biosynthesis, Oxidative polymerization, Peroxidases  相似文献   
104.
Annals of Botany83: 535–541, 1999 It is regretted that Figure 1 of this paper was incorrect; itshould have appeared as follows: Fig. 1. Genomic organization of new repetitive sequences. Southernblots of field bean genomic DNA digested using various restrictionenzymes (H, Hind III; Hc, Hinc II; T,Taq I; A, Alu I; R, RsaI; M, Mbo I; F, Fok I) were probed with the individual repeats.The bands from which the sequences were isolated are markedby arrows. The bands from which full length sequence of T133and TIII17 repeats were isolated are marked by asterisks.  相似文献   
105.
The hydraulic conductivity of plant roots (Lpr) is determined in large part by the activity of aquaporins. Mechanisms occurring at the post‐translational level, in particular phosphorylation of aquaporins of the plasma membrane intrinsic protein 2 (PIP2) subfamily, are thought to be of critical importance for regulating root water transport. However, knowledge of protein kinases and phosphatases acting on aquaporin function is still scarce. In the present work, we investigated the Lpr of knockout Arabidopsis plants for four Ca2+‐dependent protein kinases. cpk7 plants showed a 30% increase in Lpr because of a higher aquaporin activity. A quantitative proteomic analysis of wild‐type and cpk7 plants revealed that PIP gene expression and PIP protein quantity were not correlated and that CPK7 has no effect on PIP2 phosphorylation. In contrast, CPK7 exerts a negative control on the cellular abundance of PIP1s, which likely accounts for the higher Lpr of cpk7. In addition, this study revealed that the cellular amount of a few additional proteins including membrane transporters is controlled by CPK7. The overall work provides evidence for CPK7‐dependent stability of specific membrane proteins.  相似文献   
106.
Systematic studies on the family Phytoseiidae were first conducted at the beginning of the 20th century but increased greatly after the Second World War. Various classifications have been proposed based on different characters such as: dorsal, ventral, and leg chaetotaxy; the shape of ventrianal and sternal shields; the shape of the insemination apparatus (spermatheca) and spermatodactylus; the number of teeth on the movable digit of chelicera; and dorsal and ventral adenotaxy. The genus concepts developed over the last five decades can be divided into two main categories or hypotheses. The first, supported mainly by Chant and McMurtry, focuses on dorsal and ventral chaetotaxy, and the genera so defined usually include a great number of species. The second category, proposed by Athias‐Henriot, considers the shape of the insemination apparatus as the key character, and the genera so defined usually include a limited number of species. From a diagnostic point of view, both classifications have a valid structure, but the question investigated herein was: which of the two classifications or hypotheses fits phylogenetic evolution? To answer this, we conducted molecular phylogenetic analyses (using the genes ITS and 12S rRNA) on the genus Neoseiulus, which has been subjected to classification based on the two main genus concepts. The results showed that the first hypothesis (Chant and McMurtry) leads to polyphyly of the genus Neoseiulus, while the second (Athias‐Henriot) leads to paraphyly of the genus. The results show that acarologists who first decided that the insemination apparatus was of evolutive importance could be correct as the shape of the insemination apparatus seems to better fit evolutive clades than dorsal and ventral chaetotaxy. The morphology of this organ, however, must be more accurately studied to better define homologies. The present paper investigates the two main hypotheses proposed until now for classification of Phytoseiidae and thereby opens the way for improved classification. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 253–273.  相似文献   
107.
We briefly review the potential history of Madagascar as either a Darwinian or a Wallacean island, summarize the phylogenetic evidence regarding the biogeography of Madagascar spiders, examine the dispersal history of the Madagascar Phyxelididae, and monograph the family in Madagascar. Molecular phylogenetic analyses for 32 Malagasy phyxelidid exemplars, nine confamilial outgroup taxa, and seven other more distant outgroups are performed for three nuclear markers and one mitochondrial genetic marker (28S, 18S, H3 and COI) utilizing Bayesian, maximum‐likelihood and parsimony methods. These analyses suggest that there are 14 species of Phyxelididae that may be recognized from Madagascar, that these may be divided into three genera, and that the Malagasy phyxelidids form a monophyletic group, probably resulting from a single invasion of the island by an ancestor from Africa. Two new genera, ten new species, and two new combinations are proposed: Manampoka atsimo gen. nov., sp. nov. ; Rahavavy gen. nov. , including R. ida sp. nov. and R. fanivelona (Griswold, 1990) comb. nov. and R. malagasyana (Griswold, 1990) comb. nov. ; and Ambohima andrefana sp. nov. , A. antsinanana sp. nov. , A. avaratra sp. nov. , A. maizina sp. nov. , A. ranohira sp. nov. , A. vato sp. nov. , A. zandry sp. nov. and A. zoky sp. nov. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 728–810.  相似文献   
108.
Linear regression and cumulative sum analysis (CUSUM) change point analyses were used to determine whether there had been a significant change in the first flowering date between 1983 and 2006 for 65 species. Both methods agreed that the first flowering date of 47 species did not change and that eight species had a significant change (P < 0.05) in their flowering. Three species shifted to later flowering and five species to earlier. Over the observation period, each method found that the average shift to later flowering was greater (37.4 days or approx. 1.56 days per year for CUSUM change point analysis and 51.4 days or 2.14 days per year for linear regression) than that to earlier flowering (28.4 days or approx. 1.20 days per year for change point analysis and 46.5 days or 1.97 days per year for linear regression). For the remaining 10 species the results of linear regression and change point methods differed. Each method found five species (three earlier flowering and two later) to have a significantly changed first flowering date over their observation period, where the other method did not. Some of these differences can be attributed to the fact that the CUSUM method can detect multiple change points whereas linear regression can not. Significant change points in first flowering date were identified for 13 species between the years 1987 to 1998. The most frequent year identified as a change point year was 1995. The two methods, although not interchangeable, had strong agreement (84.6%) in detecting shifts. This gives greater confidence that a change in flowering has occurred for eight species and equally importantly, that no change in first flowering date has occurred for 47 species.  相似文献   
109.
Background: As actors with the key responsibility for the protection of human research participants, Research Ethics Committees (RECs) need to be competent and well‐resourced in order to fulfil their roles. Despite recent programs designed to strengthen RECs in Africa, much more needs to be accomplished before these committees can function optimally. Objective: To assess training needs for biomedical research ethics evaluation among targeted countries. Methods: Members of RECs operating in three targeted African countries were surveyed between August and November 2007. Before implementing the survey, ethical approvals were obtained from RECs in Switzerland, Cameroon, Mali and Tanzania. Data were collected using a semi‐structured questionnaire in English and in French. Results: A total of 74 respondents participated in the study. The participation rate was 68%. Seventy one percent of respondents reported having received some training in research ethics evaluation. This training was given by national institutions (31%) and international institutions (69%). Researchers and REC members were ranked as the top target audiences to be trained. Of 32 topics, the top five training priorities were: basic ethical principles, coverage of applicable laws and regulations, how to conduct ethics review, evaluating informed consent processes and the role of the REC. Conclusion: Although the majority of REC members in the targeted African countries had received training in ethics, they expressed a need for additional training. The results of this survey have been used to design a training program in research ethics evaluation that meets this need.  相似文献   
110.
Socialization, Land, and Citizenship among Aboriginal Australians: Reconciling Indigenous and Western Forms of Education . Raymond Matthew Nichol. Lewiston, NY: Edward Mellen Press, 2005. 480 pp.  相似文献   
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