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151.

Background

Point of care testing (PoCT) may be a useful adjunct in the management of chronic conditions in general practice (GP). The provision of pathology test results at the time of the consultation could lead to enhanced clinical management, better health outcomes, greater convenience and satisfaction for patients and general practitioners (GPs), and savings in costs and time. It could also result in inappropriate testing, increased consultations and poor health outcomes resulting from inaccurate results. Currently there are very few randomised controlled trials (RCTs) in GP that have investigated these aspects of PoCT.

Design/Methods

The Point of Care Testing in General Practice Trial (PoCT Trial) was an Australian Government funded multi-centre, cluster randomised controlled trial to determine the safety, clinical effectiveness, cost effectiveness and satisfaction of PoCT in a GP setting. The PoCT Trial covered an 18 month period with the intervention consisting of the use of PoCT for seven tests used in the management of patients with diabetes, hyperlipidaemia and patients on anticoagulant therapy. The primary outcome measure was the proportion of patients within target range, a measure of therapeutic control. In addition, the PoCT Trial investigated the safety of PoCT, impact of PoCT on patient compliance to medication, stakeholder satisfaction, cost effectiveness of PoCT versus laboratory testing, and influence of geographic location.

Discussion

The paper provides an overview of the Trial Design, the rationale for the research methodology chosen and how the Trial was implemented in a GP environment. The evaluation protocol and data collection processes took into account the large number of patients, the broad range of practice types distributed over a large geographic area, and the inclusion of pathology test results from multiple pathology laboratories. The evaluation protocol developed reflects the complexity of the Trial setting, the Trial Design and the approach taken within the funding provided. The PoCT Trial is regarded as a pragmatic RCT, evaluating the effectiveness of implementing PoCT in GP and every effort was made to ensure that, in these circumstances, internal and external validity was maintained.

Trial Registration

12612605000272695  相似文献   
152.
Zirconyl hematoxylin stains acidic mucins darkly and specifically using a solution of 100 mg hematoxylin, 5 ml ethanol, 5 ml 0.5% sodium iodate, 400 mg zirconyl chloride octahydrate, and 30 ml 25% aqueous glycerol. The stain is especially advantageous for studying goblet cells and Paget cells.  相似文献   
153.
We have developed a digital image processing technique based on highpass filtering of microfluorimetric images for selective transmission of fine image details corresponding to mitochondria. This technique enabled the detection of the mitochondrial calcium signals with high selectivity, simultaneously with the cytosolic calcium signal. The validity of this technique was supported in primary cultures of rat brain capillary endothelial cells loaded with X-rhod-1 by the results that (i) inhibition of the mitochondrial Ca2+ uptake by discharging the mitochondrial membrane potential selectively abolished the transient of the highpass filtered signal evoked by ATP, and (ii) CGP-37157, a selective blocker of the mitochondrial Na+/Ca2+ exchanger, increased the peak amplitude of highpass filtered (mitochondrial) Ca2+ transients and caused a sustained plateau. The highpass filtering technique enabled the analysis of the mitochondrial Ca2+ transients in high temporal resolution. We found a uniform and monophasic rise of [Ca2+] in the mitochondrial population of the cell, following the cytosolic [Ca2+] with a delay at onset and peak. The introduced highpass filtering technique is a powerful tool in the high spatial and temporal resolution analysis of mitochondrial calcium transients, and it could be especially important in specimens where genetically targeted probes fail.  相似文献   
154.
Integrated chorda tympani nerve responses to NaCl were studied in two mouse strains, an NaCl-preferring NZB/B1NJ and an NaCl-avoiding CBA/J. The NaCl responses of both strains had similar magnitude and were suppressed by amiloride to a similar extent. This suggests that peripheral gustatory responsiveness to NaCl is not the only mechanism underlying mouse strain variation in NaCl acceptance.   相似文献   
155.
Higher plant plasma membranes carry receptors of different affinity for the phytotoxin fusicoccin. Reception of fusicoccin involves proteins belonging to the highly conserved 14-3-3 family, but the complete structure of the fusicoccin receptor (FCR) is unknown. Using radiation inactivation analysis, we estimated the molecular masses of low-affinity and high-affinity FCR at 63 +/- 7 and 130 +/- 15 kD, respectively. The dose dependences of receptor inactivation indicate that microsomal specimens contain "silent" FCRs of 420 +/- 90 kD in amounts commensurate with that of the active FCRs. Both low- and high-affinity FCRs are inactivated by hydrolytic enzymes from the outer surface of the plasma membrane, and impairment of protoplast integrity causes an irreversible transition of the low-affinity binding site into the high-affinity one. A scheme is proposed for the organization of different types of FCR in the plasma membrane, implying that the membrane affinity for fusicoccin reflects the interaction between proteins in the FCR complex.  相似文献   
156.
157.
Enhancement of the erythroid maturation in Friend virus-induced leukemic cells has been examined in vitro by the treatment with dimethyl sulfoxide (DMSO). Although the cell growth was inhibited in the medium containing 2% DMSO, many cells remained viable for a week. By the 3rd day of the culture, the cells treated with DMSO became more strongly agglutinated by phytohemagglutinin than the cells incubated without DMSO. Mouse erythrocyte membrane-specific antigens were also detectable at the 4th day. At the 8th day of the culture hemoglobin synthesis was apparently demonstrated in the cells treated with DMSO, which could not be seen in the untreated cells. Maturation or differentiation along the erythroid pathway in Friend leukemic cells by DMSO is discussed on these markers.  相似文献   
158.
A high cell density cultivation (HCDC) for growth of Escherichia coli in an especially designed glucose/mineral salt medium is proposed. The HCDC essentially starts as a batch process which is followed by a two-phase fed-batch cultivation. After unlimited growth at mu max = 0.45 h-1 in the batch part, growth was controlled at a reduced specific growth rate (mu = 0.11 h-1 less than mu max) over a period of 3 doubling times in which the biomass concentration increased from 12 to 95 g 1(-1) (phase 1 of fed-batch cultivation). Control of growth (mu) was realized by a PO2 control loop (by variation of glucose feeding) and a mu control loop (by variation of agitation speed N) while the actual mu was calculated from the off-gas composition. If the agitation rate cannot be increased anymore the mu controller is switched off (end of phase 1). In the following phase 2, mu declines, however, the still acting pO2 (glucose) controller guarantees sufficient O2 supply till the end of the cultivation with a biomass concentration of 110 g 1(-1) (dry mass). The proposed HCDC suppresses generation of inhibitory by-products and the high yield coefficients indicate the economy of the process.  相似文献   
159.
Summary A defined medium was developed which, by means of a specific fed-batch mode, allows growth of the recombinant Escherichia coli strain TG1 (pBB210) up to a cell density of 60 g dry weight/l. Apart from glucose and aqueous ammonia fed as carbon and nitrogen sources, it was unnecessary to supply other nutrients or O2-enriched air. Aqueous ammonia also served for pH control. The pO2 level was kept at 20% saturation via closed-loop controls operating the two output variables of stirrer speed and glucose feeding rate. This fed-batch method prevented significant accumulation of acetate and other metabolic by-products. The recombinant E. coli expressed interferon alpha 1 more efficiently at a lower specific growth rate (Pr 0.15 h–1) than at the maximum specific growth rate (max = 0.45 h–1). Therefore, fermentation in the batch phase at max was only allowed to continue up to a medium cell density. In the succeeding fed-batch phase, the specific growth rate was reduced to Pr by increasing the stirrer speed according to an empirically developed time scale. Offprint requests to: D. Riesenberg  相似文献   
160.

Background

For brown bears (Ursus arctos), hibernation is a critical part of the annual life cycle because energy savings during hibernation can be crucial for overwintering, and females give birth to cubs at that time. For hibernation to be a useful strategy, timing is critical. However, environmental conditions vary greatly, which might have a negative effect on the functionality of the evolved biological time-keeping. Here, we used a long-term dataset (69 years) on brown bear denning phenology recorded in 12 Russian protected areas and quantified the phenological responses to variation in temperature and snow depth. Previous studies analyzing the relationship between climate and denning behavior did not consider that the brown bear response to variation in climatic factors might vary through a period preceding den entry and exit. We hypothesized that there is a seasonal sensitivity pattern of bear denning phenology in response to variation in climatic conditions, such that the effect of climatic variability will be pronounced only when it occurs close to den exit and entry dates.

Results

We found that brown bears are most sensitive to climatic variations around the observed first den exit and last entry dates, such that an increase/decrease in temperature in the periods closer to the first den exit and last entry dates have a greater influence on the denning dates than in other periods.

Conclusions

Our study shows that climatic factors are modulating brown bear hibernation phenology and provide a further structuring of this modulation. The sensitivity of brown bears to changes in climatic factors during hibernation might affect their ability to cope with global climate change. Therefore, understanding these processes will be essential for informed management of biodiversity in a changing world.
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