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81.
The purpose of this study was to gain a better understanding of stock-type horse show competitors' understanding of welfare and level of concern for stock-type show horses' welfare. Data were collected through an online questionnaire that included questions relating to (a) interest and general understanding of horse welfare, (b) welfare concerns of the horse show industry and specifically the stock-type horse show industry, (c) decision-making influences, and (d) level of empathic characteristics. The majority of respondents indicated they agree or strongly agree that physical metrics should be a factor when assessing horse welfare, while fewer agreed that behavioral and mental metrics should be a factor. Respondent empathy levels were moderate to high and were positively correlated with the belief that mental and behavioral metrics should be a factor in assessing horse welfare. Respondents indicated the inhumane practices that most often occur at stock-type shows include excessive jerking on reins, excessive spurring, and induced excessive unnatural movement. Additionally, respondents indicated association rules, hired trainers, and hired riding instructors are the most influential regarding the decisions they make related to their horses' care and treatment.  相似文献   
82.
Proteins containing the post-translationally modified amino acid L-3,4-dihydroxyphenylalanine (DOPA) undergo autosclerotization as a means of assuring cohesive resilience in many structural matrices found in nature. To explore the chemical mechanism of sclerotization, we examined the oxidation products of relatively simple analogs of a peptidyl DOPA residue, such as N-acetylDOPA ethyl ester and N-acetyldopamide, together with those of several oligopeptides. Oxidation, induced by either of two catecholoxidases or by sodium periodate, resulted in the Lewis base catalyzed formation of derivatives of the unusual amino acid 3,4-dihydroxy-alpha,beta-dehydroDOPA (delta DOPA). The N-acetyl delta DOPA ethyl ester representative of this group of derivatives was characterized by NMR and uv spectroscopy. A variety of peptides developed analogous uv spectra upon oxidation. A similar reaction was observed upon oxidation of 3,4-dihydroxyphenylpropanoic (dihydrocaffeic) acid, but not after oxidation of N-acetyldopamine. Evidence is presented that this conversion is the result of a rearrangement of the DOPA quinone moiety to its delta DOPA tautomer, and that this tautomerization can be a dominant fate for peptidyl DOPA quinone, provided a Lewis base catalyst is available and competing reactions are minimized. Formation of delta DOPA in natural or synthetic polymers would increase the variety of crosslinks available to sclerotizing matrices. delta DOPA has been found in naturally occurring oligopeptides isolated by other workers from several marine species.  相似文献   
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BackgroundLifestyle modification is widely recommended to kidney allograft recipients post transplantation due to the cardiometabolic risks associated with immunosuppression including new-onset diabetes, weight gain and cardiovascular events. However, we have no actual evidence that undertaking lifestyle modification protects from any adverse outcomes post transplantation. The aim of this study is to compare whether a more proactive versus passive interventional approach to modify lifestyle is associated with superior outcomes post kidney transplantation.Methods/designWe designed this prospective, single-centre, open-label, randomised controlled study to compare the efficacy of active versus passive lifestyle intervention for kidney allograft recipients early post transplantation. A total of 130 eligible patients, who are stable, nondiabetic and between 3 and 24 months post kidney transplantation, will be recruited. Randomisation is being undertaken by random block permutations into passive (n = 65, leaflet guidance only) versus active lifestyle modification (n = 65, supervised intervention) over a 6-month period. Supervised intervention is being facilitated by two dietitians during the 6-month intervention period to provide continuous lifestyle intervention guidance, support and encouragement. Both dietitians are accredited with behavioural intervention skills and will utilise motivational aids to support study recruits randomised to active intervention. The primary outcome is change in abnormal glucose metabolism parameters after 6 months of comparing active versus passive lifestyle intervention. Secondary outcomes include changes in a wide array of cardiometabolic parameters, kidney allograft function and patient-reported outcome measures. Long-term tracking of patients via data linkage to electronic patient records and national registries will facilitate long-term comparison of outcomes after active versus passive lifestyle intervention beyond the 6-month intervention period.DiscussionThis is the first randomised controlled study to investigate the benefits of active versus passive lifestyle intervention in kidney allograft recipients for the prevention of abnormal cardiometabolic outcomes. In addition, this is the first example of utilising behaviour therapy intervention post kidney transplantation to achieve clinically beneficial outcomes, which has potential implications on many spheres of post-transplant care.

Trial registration

This study was registered with the Clinical Trials Registry on 27 August 2014 (ClinicalTrials.org Identifier: NCT02233491).  相似文献   
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Highly purified mitochondria from rat liver contain a phospholipase A that catalyzes removal of 2-fatty acids, with a pH optimum above pH 8.0. Lysosomal preparations appeared to have two phospholipases A associated with them, one with a pH optimum at about pH 4.0, the second between pH 6.0 and 7.0. Mitochondrial phospholipase A hydrolyzed exogenous phospholipid as fast as or faster than endogenous phospholipid. The difference in specific radioactivity of (14)C-ethanolamine-labeled endogenous mitochondrial phospholipid before and after incubation indicates that a fraction of mitochondrial phosphatidyl ethanolamine is hydrolyzed more rapidly than the mitochondrial phospholipids as a whole. Acyl bond hydrolysis of exogenous and endogenous phospholipid by mitochondria was stimulated by free fatty acid, Ca(++), or in certain cases, monoacyl phospholipids or by treatments that disrupt the mitochondrial membrane. Of various fatty acids tested, lauric, myristic, oleic, and linoleic were most effective. ADP and ATP inhibited mitochondrial phospholipase, probably because they compete for Ca(++). Mg(++) also behaved as a competitive inhibitor; the effect was overcome by relatively little Ca(++).  相似文献   
87.
Many investigations have indicated a functional role for carbonic anhydrase in the mediation of hormone-stimulated bone resorption. These studies depend heavily on the use of heterocyclic sulfonamide inhibitors of carbonic anhydrase. These drugs have effects on many tissues other than bone, and some of these effects confound the interpretation of studies of the role of carbonic acid in bone metabolism. A novel, "bone-targeted" sulfonamide has been produced to obviate these extraosseous effects. This compound (designated WP-1) is the combination of tetracycline and acetazolamide, such that the acetazolamide is not an active inhibitor. Hydrolysis of WP-1 yields an active carbonic anhydrase inhibitor. WP-1 has a marked affinity for bone mineral, allowing deposition of the drug in bone. At a concentration of 10(-5) M, WP-1 attenuates parathyroid hormone stimulated net release of calcium from neonatal rat calvaria in culture. WP-1 is the first member of a class of drugs which may prove useful as pharmacological probes in the study of bone metabolism.  相似文献   
88.
Release of Sindbis virus from infected cells is inhibited by lowering the ionic strength of the medium. To determine the nature of the inhibited step, we examined, by electron microscopy, both freeze-etched and thin-sectioned preparations which had been fixed with either glutaraldehyde or formaldehyde. Inhibitory medium had two different effects on Sindbis virus release: virus budding was partially inhibited, and those virions which did mature were precipitated on the surface of the cell. Freeze-etched, inhibited cells showed very few viral buds. After shift to normal medium, the number of budding virions increased dramatically, far exceeding the quantity found in normal controls. Thus, low ionic strength medium clearly inhibited an early stage of virus maturation. The results were the same regardless of the fixative. Thin sections of glutaraldehyde-fixed, inhibited cells contained large extracellular aggregates of mature virus which were not present in similar, formaldehyde-fixed preparations. Fixation of radioactively-labeled, inhibited cultures revealed that approximately half of the virus that could be released from inhibited cells by raising the ionic strength of the medium could also be released by formaldehyde, but not by glutaraldehyde. This fraction probably represents mature virus attached to the cell surface by the ionic conditions.  相似文献   
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90.
The present studies demonstrate that the intracellular fluorochromes calcein and hydroethidine can be used for quantification of effector-target conjugates involving cloned human natural killer (NK) or interleukin-2 (IL-2) activated human lymphokine activated killer (LAK) cells by dual color flow cytometry without potential artifacts that might result from extensive modification of effector and/or target cell membranes. Cloned NK cells and LAK cells form conjugates with cultured cell lines regardless of susceptibility to lysis. The strength of the interactions in these conjugates was investigated using a variable speed vortexer. Even relatively gentle vortexing disrupted most conjugates involving fresh human peripheral blood lymphocytes (PBL) but only about one-fourth of conjugates between K-562 cells and human PBL that had been cultured with or without IL-2 by this treatment. The rate of conjugate formation for LAK cells was determined to be about 3 times faster than for cloned NK cells, and both rates are considerably faster than the reported rate of formation of cytotoxic T lymphocyte (CTL) target conjugates. The differences in the rate of conjugate formation are apparently not related to target cell specificity, since LAK cells form conjugates with susceptible and resistant cell lines at comparable rates. When effector-target conjugates are incubated at 37 degrees C in the absence of calcium--thereby precluding lysis--the percentage of conjugated LAK or cloned NK cells decreases logarithmically with time. These results suggest that an initial equilibrium between free and conjugated lymphocytes gradually shifts in favor of unconjugated cells.  相似文献   
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