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1.
ObjectivesWe introduced the cohort studies included in the Korean Cohort Consortium (KCC), focusing on large-scale cohort studies established in Korea with a prolonged follow-up period. Moreover, we also provided projections of the follow-up and estimates of the sample size that would be necessary for big-data analyses based on pooling established cohort studies, including population-based genomic studies.MethodsWe mainly focused on the characteristics of individual cohort studies from the KCC. We developed “PROFAN”, a Shiny application for projecting the follow-up period to achieve a certain number of cases when pooling established cohort studies. As examples, we projected the follow-up periods for 5000 cases of gastric cancer, 2500 cases of prostate and breast cancer, and 500 cases of non-Hodgkin lymphoma. The sample sizes for sequencing-based analyses based on a 1:1 case-control study were also calculated.ResultsThe KCC consisted of 8 individual cohort studies, of which 3 were community-based and 5 were health screening-based cohorts. The population-based cohort studies were mainly organized by Korean government agencies and research institutes. The projected follow-up period was at least 10 years to achieve 5000 cases based on a cohort of 0.5 million participants. The mean of the minimum to maximum sample sizes for performing sequencing analyses was 5917–72 102.ConclusionsWe propose an approach to establish a large-scale consortium based on the standardization and harmonization of existing cohort studies to obtain adequate statistical power with a sufficient sample size to analyze high-risk groups or rare cancer subtypes.  相似文献   
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Fatigability is defined as the extent of fatigue in the context of activity and differs from the term used in exercise literature to describe muscle endurance characteristics. Many fatigability measures are available, but no studies have thoroughly evaluated them for adequate incorporation of fatigability concepts. This integrative review provides an overall assessment of existing fatigability measures and then evaluates each in depth. A database search and hand search produced 14 studies for review. Fatigability measurement took three forms: self-reported fatigability, perceived fatigability (self-reported fatigue following a defined performance test), and performance fatigability (performance deterioration). Of 17 measures identified, validity and/or reliability was reported for six (35.3%), and no measure was used in more than one study. Fatigability measures have been correlated with clinical measures, indicating that fatigability should be measured during routine clinical health screening. Refinement of measures and additional fatigability data collection will improve understanding and treatment of fatigue.  相似文献   
4.

Purpose

Multiple chemical sensitivity (MCS) is a clinical syndrome representing multi-organ and psychological symptoms caused by chronic exposure to various chemicals in low concentrations. We evaluated the prevalence and related factors of MCS targeting Korean adults using the Quick Environmental Exposure and Sensitivity Inventory (QEESI©).

Methods

A total of 446 participants were recruited from Severance Hospital. Participants underwent a questionnaire interview including questions on sociodemographic factors, occupational and environmental factors, allergic diseases, and the QEESI©. Among them, 379 participants completed the questionnaire and the QEESI©. According to the QEESI© interpretation results, participants were divided into very suggestive (VS) group and less suggestive (LS) group.

Results

The estimated prevalence of MCS was higher in allergic patients than non-allergic participants (19.7% and 11.3%, respectively, P=0.04). In the multivariate logistic regression analysis, ages of 30-39 (OR, 2.94; 95% CI, 1.25-6.95) and those of 40-49 (OR, 2.51; 95% CI, 1.02-6.21) were significantly related to MCS compared to those aged less than 30 years. Female sex (OR, 2.16; 95% CI, 1.11-4.18), experience of dwelling in a new house (OR, 2.05; 95% CI, 1.04-4.03), and atopic dermatitis (OR, 1.95; 95% CI, 1.04-3.69) were also significantly related to MCS. However, only age of 30-39 in the allergic group was significant in the stratified analysis.

Conclusions

The estimated prevalence of MCS was higher among allergic patients than non-allergic participants. People with experience of dwelling in a new house and atopic dermatitis were more at risk of being intolerant to chemicals. Further studies to provide the nationally representative prevalence data and clarify risk factors and mechanisms of MCS are required.  相似文献   
5.
BACKGROUND/AIMS: Unilateral ureteral obstruction (UUO) in rats has been used as a model of renal interstitial fibrosis, in which therapeutic trials can be of important clinical relevance. In this study, we investigated the effects of mycophenolate mofetil (MMF), the angiotensin-converting enzyme (ACE) inhibitor lisinopril (L), and the combination of both drugs, given daily for 14 days to UUO rats, on the renal fibrogenic process triggered by UUO. METHODS: Rats underwent surgical UUO, followed by treatment with daily doses of either MMF, lisinopril, or both, and were then sacrificed after 14 days. Kidney fragments were fixed for histopathological examination (hematoxylin-eosin and periodic acid-Schiff reactive) and immunohistochemistry for myofibroblasts (alpha-smooth muscle actin; alpha-SMA) and macrophages (ED-1). Histomorphometrical analysis of collagen was performed with Sirius red staining, and collagen content was assessed by the amount of hydroxyproline. Cortex and medulla were analyzed separately. RESULTS: MMF, lisinopril and MMF+L reduced the density of alpha-SMA- and ED-1-positive cells (p < 0.05), interstitial volume (p < 0.05) and decreased Sirius-red-stained areas by 54.6, 35.6 and 58.0%, and hydroxyproline content by 60.1, 49.7 and 62.7%, respectively. No differences were observed among treated groups. CONCLUSION: MMF and the ACE inhibitor lisinopril attenuated the progression of the fibrogenic process of UUO in an equivalent manner. The combination of both drugs did not add any further improvement in the collagen content.  相似文献   
6.
Lee I  Kesner RP 《Hippocampus》2004,14(3):301-310
The hippocampus is an essential neural structure in developing contextual memory in a situation in which rapid development of associative learning should occur. We tested a subregion-specific contribution in the hippocampus to memory acquisition and retrieval, using the contextual fear-conditioning paradigm. The current results suggest that all three subregions (i.e., CA3, CA1, and dentate gyrus) of the hippocampus contribute to rapid acquisition of contextual memory in the initial phase of acquisition. The involvement of CA3 seems to be important at the earliest stage of acquisition, presumably for developing instant representation of a context. The role of CA3, however, was minimal in retrieving contextual memory after a long time period (i.e., 24 h), whereas the other subregions (i.e., CA1 and dentate gyrus) were critically involved. The results indicate time-dependent differential contributions of the hippocampal subregions to memory acquisition and retrieval in contextual fear-conditioning.  相似文献   
7.
Lee I  Kesner RP 《Hippocampus》2004,14(1):66-76
The hippocampus is an essential neural structure for spatial memory. Computational models suggest that the CA3 subregion of the hippocampus plays an essential role in encoding and retrieval of spatial memory. The perforant path (PPCA3) and dentate gyrus (DG)-mediated mossy fibers (MFs) compose major afferent inputs into CA3. A possible functional dissociation between these afferent inputs was attempted using a simple navigation test (i.e., the modified Hebb-Williams maze). Behavioral testing was combined with electrolytic lesions of PPCA3 or neurotoxic lesions of the DG, to eliminate each afferent input into CA3. Lesions in either afferent input into CA3 affected learning of an effective navigational path on the maze. The contributions of the two CA3 afferent inputs, however, were different regarding encoding and retrieval of memory measured based on indices operationally defined for the behavioral paradigm (i.e., encoding, the number of errors reduced within a day; retrieval, the number of errors reduced between days). The DG-lesioned animals exhibited deficits regarding the encoding index, but not the retrieval index, whereas the PPCA3-lesioned rats displayed deficits regarding the retrieval index, but not the encoding index. The results suggest that the two major afferent inputs of CA3 may contribute differentially to encoding and retrieval of spatial memory.  相似文献   
8.
We examined the iron nutritional status of healthy term infants in a longitudinal study from 15 through 365 days of age. All infants were fed according to the present austrian recommendations. Serum hemoglobin (Hb) decreased from 15 through 122 days of age and remained constant thereafter. At 365 days of age, only 4.7% of the infants had hemoglobin levels below 11 g/dl, which is considered the borderline value for anemia. Mean corpuscular volume (MCV) of erythrocytes was changing during infancy. Free erythrocyte protoporphyrin (FEP) was constant from 122 days through 365 days of age. The upper normal value of 3 micrograms/gHb for infants older than 122 days of age corresponded to that for children older than one year and adults. Serum ferritin (SF) decreased from 15 through 183 days of age and remained constant thereafter. At 365 days of age, only 9.3% of the infants had SF below 10 micrograms/l, which is considered the borderline concentration for depletion of iron stores. We found no differences of iron nutritional status between infants who were breastfed longer than 122 days and infants who were breastfed shorter than 122 days or were fed formula. Our findings indicate that the prevalence of iron deficiency anemia and depletion of the iron stores is lower than in previous studies. Changes in infant nutrition during the last years resulted in higher iron intake and lower prevalence of iron deficiency.  相似文献   
9.
A survey of 25 hospitals in Nigeria has been conducted to assess the level of compliance to the Commission for European Communities (CEC) criteria for good radiographic practice in four adult radiographic examinations. Chest, skull, abdominal and lumbar spine radiographic examinations were assessed. Using a simple scoring system of ‘0’ for unfulfilled and ‘1’ for fulfilled criteria, the results show an average compliance level of 50 ± 8% for chest, 57 ± 8% for skull, 56 ± 10% for abdomen and 51 ± 7% for lumbar spine radiography. Findings show that the level of compliance could be corrected by the adoption of quality control programmes in the country.  相似文献   
10.
Place cells in the hippocampus fire at specific positions in space, and distal cues in the environment play critical roles in determining the spatial firing patterns of place cells. Many studies have shown that place fields are influenced by distal cues in foraging animals. However, it is largely unknown whether distal‐cue‐dependent changes in place fields appear in different ways in a memory task if distal cues bear direct significance to achieving goals. We investigated this possibility in this study. Rats were trained to choose different spatial positions in a radial arm in association with distal cue configurations formed by visual cue sets attached to movable curtains around the apparatus. The animals were initially trained to associate readily discernible distal cue configurations (0° vs. 80° angular separation between distal cue sets) with different food‐well positions and then later experienced ambiguous cue configurations (14° and 66°) intermixed with the original cue configurations. Rats showed no difficulty in transferring the associated memory formed for the original cue configurations when similar cue configurations were presented. Place field positions remained at the same locations across different cue configurations, whereas stability and coherence of spatial firing patterns were significantly disrupted when ambiguous cue configurations were introduced. Furthermore, the spatial representation was extended backward and skewed more negatively at the population level when processing ambiguous cue configurations, compared with when processing the original cue configurations only. This effect was more salient for large cue‐separation conditions than for small cue‐separation conditions. No significant rate remapping was observed across distal cue configurations. These findings suggest that place cells in the hippocampus dynamically change their detailed firing characteristics in response to a modified cue environment and that some of the firing properties previously reported in a foraging task might carry more functional weight than others when tested in a distal‐cue‐dependent memory task. © 2016 Wiley Periodicals, Inc.  相似文献   
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