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41.
During a four-year study period 43 985 patients were seen in the treatment room and 61 806 coded procedures carried out. Thirty per cent of these procedures were not part of usual nursing curricula and required initial supervision and assessment or training (or both). Nearly 15% of the patients seen were making a first visit and did not require referral to a doctor. A further 17% were also making a first visit but were referred to a doctor. The treatment room made an important contribution to the work of the practice, but this would not have been possible if the staff concerned had been attached nurses requiring area health authority authorisation for procedures carried out as opposed to practice nurses for whom procedures were authorised on a personal basis.  相似文献   
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This study sets out to provide a systematic analysis of the development of the primordial central nervous system (CNS) in embryos of two decapod crustaceans, the Australian crayfish Cherax destructor (Malacostraca, Decapoda, Astacida) and the parthenogenetic Marbled crayfish (Marmorkrebs, Malacostraca, Decapoda, Astacida) by histochemical labelling with phalloidin, a general marker for actin. One goal of our study was to examine the neurogenesis in these two organisms with a higher temporal resolution than previous studies did. The second goal was to explore if there are any developmental differences between the parthenogenetic Marmorkrebs and the sexually reproducing Australian crayfish. We found that in the embryos of both species the sequence of neurogenetic events and the architecture of the embryonic CNS are identical. The naupliar neuromeres proto-, deuto-, tritocerebrum, and the mandibular neuromeres emerge simultaneously. After this “naupliar brain” has formed, there is a certain time lag before the maxilla one primordium develops and before the more caudal neuromeres follow sequentially in the characteristic anterior–posterior gradient. Because the malacostracan egg-nauplius represents a re-capitulation of a conserved ancestral information, which is expressed during development, we speculate that the naupliar brain also conserves an ancestral piece of information on how the brain architecture of an early crustacean or even arthropod ancestor may have looked like. Furthermore, we compare the architecture of the embryonic crayfish CNS to that of the brain and thoracic neuromeres in insects and discuss the similarities and differences that we found against an evolutionary background.  相似文献   
44.
It is commonly assumed that antibody responses against the influenza virus are polarized in the following manner: strong antibody responses are directed at highly variable antigenic epitopes, which consequently undergo ‘antigenic drift’, while weak antibody responses develop against conserved epitopes. As the highly variable epitopes are in a constant state of flux, current antibody-based vaccine strategies are focused on the conserved epitopes in the expectation that they will provide some level of clinical protection after appropriate boosting. Here, we use a theoretical model to suggest the existence of epitopes of low variability, which elicit a high degree of both clinical and transmission-blocking immunity. We show that several epidemiological features of influenza and its serological and molecular profiles are consistent with this model of ‘antigenic thrift’, and that identifying the protective epitopes of low variability predicted by this model could offer a more viable alternative to regularly update the influenza vaccine than exploiting responses to weakly immunogenic conserved regions.  相似文献   
45.
Life‐long neurogenesis is a characteristic feature of many vertebrate and invertebrate species. In decapod crustaceans, new neurons are added throughout life to two cell clusters containing local (cluster 9) and projection (cluster 10) interneurons in the olfactory pathway. Adult‐born neurons in clusters 9 and 10 in crayfish have the anatomical properties and chemistry of mature neurons by 6 months after birth. Here we use 5‐bromo‐2′‐deoxyuridine (BrdU) incorporation to pulse label mitotically active cells in these cell clusters, followed by a survival time of up to 8 months, during which crayfish (Cherax destructor) were sacrificed at intervals and the numbers of BrdU‐labeled cells quantified. We find a decrease in the numbers of BrdU‐labeled cells in cell cluster 10 between the first and second weeks following BrdU exposure, suggesting a period of cell death shortly after proliferation. Additional delayed cell divisions in both cell clusters are indicated by increases in labeled cells long after the BrdU clearing time. The differentiation time of these cells into neurons was defined by detection of the first immunoreactivity for the transmitter SIFamide in cluster 10 BrdU‐labeled cells, which begins at 4 weeks after BrdU labeling; the numbers of SIFamide‐labeled cells continues to increase over the following month. Experiments testing whether proliferation and survival of Cluster 10 cells are influenced by locomotor activity provided no evidence of a correlation between activity levels and cell proliferation, but suggest a strong influence of locomotor activity on cell survival. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 74: 602–615, 2014  相似文献   
46.
In the course of severe pathological conditions, such as acute liver failure and sepsis, toxic metabolites and mediators of inflammation are released into the patient's circulation. One option for the supportive treatment of these conditions is plasmapheresis, in which plasma, after being separated from the cellular components of the blood, is cleansed by adsorption of harmful molecules on polymers or activated carbon. In this work, the adsorption characteristics of activated carbon beads with levels of activation ranging from 0 to 86% were assessed for both hydrophobic compounds accumulating in liver failure (bilirubin, cholic acid, phenol and tryptophan) and cytokines (tumor necrosis factor α and interleukin-6). Progressive activation resulted in significant gradual reduction of both bulk density and mean particle size, in an increase in the specific surface area, and to changes in pore size distribution with progressive broadening of micropores. These structural changes went hand in hand with enhanced adsorption of small adsorbates, such as IL-6 and cholic acid and, to a lesser extent, also of large molecules, such as TNF-α.  相似文献   
47.
1. Relative body condition (the quantity of stored energy) is an important tool in understanding demographic variation and the ability of a population to respond to environmental stressors, varying food availability and competition. 2. A high-resolution database was used to examine causes of variation in the condition of north-east Arctic cod (Gadus morhua L.) for the period 1967-2004, over annual and monthly timescales. Community dynamics and climate variation were also tested as potential causes. 3. Temperature was shown to have a positive impact on condition at both inter- and intra-annual timescales. Inter-annually, temperature may affect stock distribution, in particular its overlap with the capelin stock. At shorter timescales it is likely that temperature directly affects the metabolism of the cod. 4. Intra-annually, the quantity of capelin in cod stomachs positively affected cod condition in the current and the preceding month for all lengths of cod. This indicated a time lag between a change in food consumption and a subsequent change in condition, or 'latency'. 5. Our study has shown that variation in temperature is a vital determinant of changes in condition, both at inter- and intra-annual timescales. Furthermore, the principle of latency has been demonstrated at the population level. Indirect effects of competition for energy-rich resources have been shown to have a negative effect on condition. This study supplements our knowledge of the implications for condition of changes in climate and in potential food resources.  相似文献   
48.

Background  

A close association between Sst I polymorphism in the 3' untranslated region of the apolipoproteinC3 (APOC3 ) gene and levels of plasma triglycerides (TG) had been reported by different investigators. Hypertriglyceridemia(HTG) is a known risk factor for coronary artery disease (CAD) in the context of Asian Indians. We conducted a study on the relationship between APOC3 SstI polymorphism (S1S1, S1S2 and S2S2 genotypes) and plasma TG levels in a group of 139 male healthy volunteers from Northern India.  相似文献   
49.
The brook silverside, Labidesthes sicculus (Cope), is unique in Canadian waters, as it completes its life cycle in 1 year. Previous studies based on scale ageing had suggested the species was an “annual,” but we confirmed this for the first time by otolith analysis. Growth rates from both back-calculation, and the Gompertz model, indicated an asymptote near the end of the summer, and average summer growth rates of 0.77 and 0.70 mm/day, respectively. The Gompertz model gave the best fit (n = 201, r = 0.744) with an L∞ of 85.4 mm TL, and instantaneous growth rate, g, of 0.0264. Back-counting daily growth increments allowed us to show that broods of young fish were produced throughout the summer, from late May to mid August, with maximum hatch taking place in mid-July. The species is a “batch” (serial) spawner, with only a fraction of the eggs ripening in the ovary and being released at as yet undetermined intervals. Eggs of the larger immature fish in the first summer developed from 0.05 to 0.21 mm in diameter (preserved) by fall, and in mature fish of the following spring and summer, developed to 1.2 mm in diameter (preserved), 1.4 mm fresh, at spawning. Attached to each egg was a filament averaging 2.0 cm in length, adhesive in nature, and presumably for attachment to vegetation. The egg also had microscopic hairs on its surface. No evidence was found to support temperature-dependant sex determination, nor were embryos or sperm found in the ovaries of spawning females, unlike Labidesthes sicculus vanhyningi, (the southern subspecies) which has internal fertilization. The Canadian species possesses a genital papilla through which the eggs were released, and an apparently much smaller male genital papilla than the southern subspecies.  相似文献   
50.
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