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71.
A new species, Paranoplocephala buryatiensis n. sp. (Cestoda:Anoplocephalidae), is described from the grey-sided vole Clethrionomys rufocanus (Sundevall) in the Republic of Buryatia (Russian Federation) and compared with P. longivaginata Chechulin & Gulyaev, 1998, a parasite of the red vole C. rutilus (Pallas) in the same region. P. buryatiensis n. sp. and P. longivaginata both have an exceptionally long vagina and cirrus, unique features among known species of Paranoplocephala Lühe, 1910. The new species differs from P. longivaginata primarily by its wider and more robust body, lower length/width ratio of mature proglottides, tendency of testes to occur in two separate groups, seminal receptacle of a different shape and the position of the cirrus-sac with respect to the ventral longitudinal osmoregulatory canal. The cytochrome oxidase subunit I (COI) sequence data support the independent status of these species, and show that they form a monophyletic assemblage within Paranoplocephala (sensu lato). Assuming cospeciation, an indirect calibration using host speciation dates estimated a rate of mtDNA substitution of 1.0–1.7% pairwise (0.5–0.85% per lineage) sequence divergence per million years. A faunistic review of Paranoplocephala species in C. rufocanus and C. rutilus in the Holarctic region is presented.  相似文献   
72.
The Semliki Forest virus (SFV) replicase protein nsP1 has methyltransferase (MT) and guanylyltransferase-like (GT) activities, which are involved in the capping of viral mRNAs. MT catalyzes the transfer of the methyl group from S-adenosylmethionine (AdoMet) to position 7 of GTP, and this reaction is followed by GT-catalyzed formation of the covalent complex m7GMP-nsP1. These reactions are virus specific and thus potential targets for inhibitors of virus replication. We have mutated residues of SFV nsP1, which are conserved in related proteins of the large alphavirus-like superfamily. Mutations of D64, D90, R93, C135, C142, and Y249 to alanine destroyed or greatly reduced the MT activity of nsP1. All MT-negative mutants lost also the GT activity, confirming that methylation of GTP is an essential prerequisite for the synthesis of the covalent guanylate complex. Mutation of H38 prevented the GT reaction without destroying MT activity. Conservation of residues essential for both reactions in the alphavirus-like superfamily implies that they use a capping mechanism similar to that for the alphaviruses. Residues D64 and D90 were necessary for AdoMet binding, as measured by UV cross-linking. Secondary structure predictions of nsP1 and other proteins of the superfamily place these residues in positions corresponding to AdoMet-binding sites of cellular methyltransferases, suggesting that they all may be structurally related.  相似文献   
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74.
A complete mitochondrial (mt) genome sequence was reconstructed from a 38,000 year-old Neandertal individual with 8341 mtDNA sequences identified among 4.8 Gb of DNA generated from approximately 0.3 g of bone. Analysis of the assembled sequence unequivocally establishes that the Neandertal mtDNA falls outside the variation of extant human mtDNAs, and allows an estimate of the divergence date between the two mtDNA lineages of 660,000 +/- 140,000 years. Of the 13 proteins encoded in the mtDNA, subunit 2 of cytochrome c oxidase of the mitochondrial electron transport chain has experienced the largest number of amino acid substitutions in human ancestors since the separation from Neandertals. There is evidence that purifying selection in the Neandertal mtDNA was reduced compared with other primate lineages, suggesting that the effective population size of Neandertals was small.  相似文献   
75.
Blood vessels of tumors carry specific markers that are usually angiogenesis-related. We previously used phage-displayed peptide libraries in vivo to identify peptides that home to tumors through the circulation and that specifically bind to the endothelia of tumor blood vessels. Here we devised a phage screening procedure that would favor tumor-homing to targets that are accessible to circulating phage, but are not blood vessels. Screening on MDA-MB-435 breast carcinoma xenografts yielded multiple copies of a phage that displays a cyclic 9-amino-acid peptide, LyP-1. Homing and binding to tumor-derived cell suspensions indicated that LyP-1 also recognizes an osteosarcoma xenograft, and spontaneous prostate and breast cancers in transgenic mice, but not two other tumor xenografts. Fluorescein-labeled LyP-1 peptide was detected in tumor structures that were positive for three lymphatic endothelial markers and negative for three blood vessel markers. LyP-1 accumulated in the nuclei of the putative lymphatic cells, and in the nuclei of tumor cells. These results suggest that tumor lymphatics carry specific markers and that it may be possible to specifically target therapies into tumor lymphatics.  相似文献   
76.
An apparently healthy Norwegian lemming (Lemmus lemmus) caught in northern Finland was observed to have a whitish body 0.5 to 1.0 mm in diameter in the external layer of the cerebral cortex. By light microscopy a highly lobulated cyst of Frenkelia sp. was observed. By transmission electron microscopy lemmus) collected in the cyst wall was seen consisting of a parasitophorous vacuolar membrane, an underlying electron-dense layer and a granular layer. The membrane was only slightly convoluted. The protrusions of the cyst wall appeared round but were often not distinctive. A very thin septum divided the interior of the cyst into compartments packed with bradyzoites and maturing zoites. The bradyzoites were elongate measuring 5-8 x 1.5-2 microm. This is the first electron microscopical study of Frenkelia sp. from L. lemmus.  相似文献   
77.
ABSTRACT: BACKGROUND: After diagnosis of a dementing illness patients and their spouses have many concerns related to the disease and their future. This often leads to poor psychological well-being and reduced health related quality of life (HRQoL) of the family. Support for self-management skills has been proven to be an effective method to improve prognosis of asthma, heart failure and osteoarthritis. However, self-management interventions have not been studied in dementia. Therefore, our aim was to examine in an objective-oriented group intervention the efficacy of self-management support program (SMP) on the HRQoL of dementia patients and their spousal caregivers as well as on the sense of competence and psychological well-being of care-givers. METHODS: During the years 2011-12, 160 dementia patients and their spouses will be recruited from memory clinics and randomized into two arms: 80 patients for group-based SMP sessions including topics selected by the participants, 80 patients will serve as controls in for usual community care. Sessions may include topics on dementia, community services, active lifestyle and prevention for cognitive decline, spousal relationship, future planning and emotional well-being. The patients and spouses will have their separate group sessions (10 participants/group) once a week for 8 weeks. Main outcome measures will be patients' HRQoL (15D) and spousal caregivers' HRQoL (RAND-36), and sense of competence (SCQ). Secondary measures will be caregivers' psychological well-being (GHQ-12) and coping resources, patients' depression, cognition and signs of frailty. Data concerning admissions to institutional care and the use and costs of health and social services will be collected during a two year follow-up. DISCUSSION: This is a "proof -of-concept" study to explore the efficacy of group support for self-management skills among dementia families. It will also provide data on cost-effectiveness of the intervention.  相似文献   
78.
ABSTRACT: BACKGROUND: Use of inappropriate drugs is common among institutionalized older people. Rigorous trials investigating the effect of the education of staff in institutionalized settings on the harm related to older people's drug treatment are still scarce. The aim of this trial is to investigate whether training professionals in assisted living facilities reduces the use of inappropriate drugs among residents and has an effect on residents' quality of life and use of health services. Methods and design During years 2011 and 2012, a sample of residents in assisted living facilities in Helsinki (approximately 212) will be recruited, having offered to participate in a trial aiming to reduce their harmful drugs. Their wards will be randomized into two arms: one, those in which staff will be trained in two half-day sessions, including case studies to identify inappropriate, anticholinergic and psychotropic drugs among their residents, and two, a control group with usual care procedures and delayed training. The intervention wards will have an appointed nurse who will be responsible for taking care of the medication of the residents on her ward, and taking any problems to the consulting doctor, who will be responsible for the overall care of the patient. The trial will last for twelve months, the assessment time points will be zero, six and twelve months. The primary outcomes will be the proportion of persons using inappropriate, anticholinergic, or more than two psychotropic drugs, and the change in the mean number of inappropriate, anticholinergic and psychotropic drugs among residents. Secondary endpoints will be, for example, the change in the mean number of drugs, the proportion of residents having significant drug-drug interactions, residents' health-related quality of life (HRQOL) according to the 15D instrument, cognition according to verbal fluency and clock-drawing tests and the use and cost of health services, especially hospitalizations. DISCUSSION: To our knowledge, this is the first large-scale randomized trial exploring whether relatively light intervention, that is, staff training, will have an effect on reducing harmful drugs and improving QOL among institutionalized older people Trial registration ACTRN12611001078943.  相似文献   
79.
An apparatus was designed for mechanical compression of cultured articular cartilage explants with acylindrical plain-ended loading head (diameter 2-5 mm) driven by a stepping motor. A load cell under the culture dish was applied for feedback regulation utilizing a microprocessor-based control unit. The operating programs allowed either continuous or cyclic loading, the latter with adjustable loading/resting ratio. The improvements in the present design compared with previously described apparatuses for similar purposes include: (1) the accurately controlled compression by a load cell and a rapid feedback circuit; (2) the wide range of selectable stresses (25 kPa-12.5 MPa) with both continuous and cyclic loading modes; (3) the ability to handle cycles as short as 1 s with 15 ms peak loading phase. Using a 4 s cycle and 0.5 MPa load for 1.5 h resulted in a significantly enhanced incorporation of radiosulphate in cultured bovine articular cartilage explants, suggesting a stimulation of proteoglycan synthesis. Light and scanning electron microscopic examinations revealed a slight depression and superficial alterations in cartilage structure at the impact site following high pressures. We expect that this apparatus will help in revealing how articular cartilage tissue and chondrocytes respond to external mechanical stimuli.  相似文献   
80.
Hiatella is one of the most widespread marine bivalve genera, occurring in diverse habitats from the temperate to polar latitudes in both hemispheres, and in fossil strata since almost 150 Myr ago. Despite variation in some biological and morphological traits, characters to resolve the current systematic structure consistently across the range of the genus are not known: all samples are often referred to a single species, Hiatella arctica (L.). Exploring the systematics of Hiatella using partial sequences of three genes (mitochondrial COI, and the nuclear ANT and 28S rRNA), we find high diversity of deep lineages (11–22% p‐distance in COI), and identify at least 13 distinct taxa both by heuristic criteria (congruence of the nuclear and mtDNA data) and by coalescence‐based analyses. At several localities, two or three of these cryptic species were found in sympatry. In the framework of previous fossil evidence and of hypotheses of paleoceanographical connections, scenarios of the phylogeny and biogeographical history of the identified species at a range of different time scales are outlined. The distinction between the main North Pacific and North Atlantic Hiatella clades and systematic diversification within each of them seem to have followed a Miocene trans‐Panamanian invasion. Apart from such earlier intra‐basin diversification, the data suggest that three successive counter‐invasions from the Pacific to the Atlantic via the Arctic Ocean route have later contributed to the current North Atlantic Hiatella diversity. These invasions probably took place in connection with (i) the Great Trans‐Arctic Biotic Interchange in the Pliocene, (ii) the last interglacial period c. 120 kya and (iii) the Holocene, postdating the last glaciation. This sequence of trans‐Arctic invasions is largely analogous to that hypothesized for some other boreal‐arctic bivalves.  相似文献   
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