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排序方式: 共有565条查询结果,搜索用时 15 毫秒
51.
Lisanne M Verweij Karin I Proper Andre NH Weel Carel TJ Hulshof Willem van Mechelen 《BMC public health》2009,9(1):461-17
Background
Occupational health professionals may play an important role in preventive health promotion activities for employees. However, due to a lack of knowledge and evidence- and practice based methods and strategies, interventions are hardly being implemented by occupational physicians to date. The aim of the Balance@Work project is to develop, evaluate, and implement an occupational health guideline aimed at the prevention of weight gain among employees. 相似文献52.
Visual identification of bacterially contaminated red cells 总被引:1,自引:0,他引:1
There have been increasing numbers of reports of transfusion-acquired Yersinia enterocolitica bacteremia (including several fatal cases). Fifteen units of whole blood were inoculated with various concentrations of Y. enterocolitica serotype 0:3 and processed into AS-3 preserved red cells (RBCs). Consistent growth of the organism was found at inoculum concentrations greater than or equal to 10 colony-forming units per mL. In all 13 units of RBCs that supported the growth of Y. enterocolitica, a darkening in color (due to hemolysis and a decrease in pO2) was observed in the bag. The attached sample segments, which were sealed from the main unit, remained sterile and did not darken. This color change was apparent in all the contaminated units by Day 35, which was 1.5 to 2 weeks after the bacteria were first detected in cultures of the blood. Hence, by comparison of the color of the segment tubing with that of the unit itself, units grossly contaminated with Y. enterocolitica can be identified prior to transfusion. Moreover, review of photographs on file at the Centers for Disease Control revealed this dramatic color change in 2 units of blood that caused transfusion-transmitted sepsis (Enterobacter agglomerans and an unidentified gram-negative bacillus, not Yersinia sp.), which demonstrated that the color change was not limited to Y. enterocolitica. This method of visual identification of contaminated units of blood could decrease the incidence of posttransfusion bacterial sepsis. 相似文献
53.
Effects of cholinergic modulation on responses of neocortical neurons to fluctuating input 总被引:1,自引:0,他引:1
Neocortical neurons in vivo are spontaneously active and intracellular
recordings have revealed strongly fluctuating membrane potentials arising
from the irregular arrival of excitatory and inhibitory synaptic
potentials. In addition to these rapid fluctuations, more slowly varying
influences from diffuse activation of neuromodulatory systems alter the
excitability of cortical neurons by modulating a variety of potassium
conductances. In particular, acetylcholine, which effects learning and
memory, reduces the slow alterhyperpolarization, which contributes to spike
frequency adaptation. We used whole-cell patch-clamp recordings of
pyramidal neurons in neocortical slices and computational simulations to
show, first, that when fluctuating inputs were added to a constant current
pulse, spike frequency adaptation was reduced as the amplitude of the
fluctuations was increased. High- frequency, high-amplitude fluctuating
inputs that resembled in vivo conditions exhibited only weak spike
frequency adaptation. Second, bath application of carbachol, a cholinergic
agonist, significantly increased the firing rate in response to a
fluctuating input but minimally displaced the spike times by < 3 ms,
comparable to the spike jitter observed when a visual stimulus is repeated
under in vivo conditions. These results suggest that cholinergic modulation
may preserve information encoded in precise spike timing, but not in
interspike intervals, and that cholinergic mechanisms other than those
involving adaptation may contribute significantly to cholinergic modulation
of learning and memory.
相似文献
54.
Gretchen Swanson Leeanne Carrothers Kristine Mulhorn 《Disability and rehabilitation》2003,25(11):665-675
This paper describes an international effort to compare disability survey questions using the ICF framework. The process included backcoding survey questions to ICF. To establish a meaningful basis for comparison, the original 14 functioning areas were scaled to seven: hearing, seeing, speaking, mobility, body movement, gripping and personal care. The names of disability topics changed reflecting ICF definitions, for example, hearing became receiving spoken messages and gripping became fine hand use . A rigorous backcoding process resulted in a comprehensive set of survey questions with unique ICF codes. It was concluded that the question format and focus must be structured to the ICF in the survey development phase in order to achieve the best possible base for international comparability. 相似文献
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58.
Mike V. Richardson PT DPT GCS COMT Amy Nordon-Craft PT DSc LeeAnne Carrothers PT PhD 《Physiotherapy theory and practice》2017,33(8):670-679
The incidence of postural orthostatic tachycardia syndrome (POTS) is estimated to be at least 500,000 in the United States and is most commonly found in premenopausal females. This syndrome shares clinical features with orthostatic hypotension (OH); however, the inclusion criteria and clinical features for POTS are not well known. The purposes of this case report are to: 1) describe the common clinical features of POTS and highlight the differences to orthostatic hypotension and 2) discuss physical therapy management of patients with POTS using exercise. A 34-year-old female with a POTS exacerbation completed a 4-week physical therapy endurance and strengthening ‘reconditioning’ program. Initial symptoms included the following: dyspnea with mild exertion, light-headedness, fatigue, leg “heaviness,” and the inability to perform normal work duties. One-mile track walk test (1-MWT) estimated VO2max improved from the 45–50th percentile to the 65–70th percentile at 8 weeks post-discharge. She returned to work full-time and resumed all previous fitness activities. The patient demonstrated clinically meaningful improvements in estimated VO2max after the “reconditioning” training. Physical therapists should be able to recognize the clinical features and inclusion criteria for POTS as part of a differential diagnosing process for patients complaining of orthostatic symptoms. 相似文献
59.
Ross AA; Cooper BW; Lazarus HM; Mackay W; Moss TJ; Ciobanu N; Tallman MS; Kennedy MJ; Davidson NE; Sweet D 《Blood》1993,82(9):2605-2610
Although peripheral blood stem cell collections (PBSC) are thought to have less tumor involvement than bone marrow (BM), the incidence of circulating tumor cells in patients with breast cancer has not been widely investigated. We prospectively investigated the incidence and viability of tumor cell involvement in PBSC and BM collections from breast cancer patients undergoing high-dose chemotherapy/hematopoietic stem cell transplantation. Paired samples of PBSC and BM from 48 patients were analyzed using an immunocytochemical technique that detects one epithelial-derived tumor cell per 5 x 10(5) mononuclear cells. Immunostained tumor cells were detected in 9.8% (13/133) PBSC specimens from 9/48 (18.7%) patients and in 62.3% (38/61) BM specimens from 32/48 (66.7%) patients, a significantly higher rate than in PBSC (P < .005). The geometric mean concentration of tumor cells in contaminated PBSC specimens was 0.8/10(5) mononuclear cells (range 0.33 to 2.0/10(5)) compared with 22.9/10(5) mononuclear cells in BM (range 1 to 3,000/10(5), P < .0001). In culture experiments, clonogenic tumor colonies grew in 21/26 immunocytochemically positive specimens. No tumor colony growth was detected in 30/32 immunocytochemically negative specimens. Immunocytochemical detection of tumor involvement in BM and PBSC correlated significantly with in vitro clonogenic growth (P < .0001). We conclude that PBSC contain fewer tumor cells than paired BM specimens from patients with advanced breast cancer and that these tumor cells appear to be capable of clonogenic growth in vitro. 相似文献
60.
Invasion of erythrocytes by Plasmodium falciparum malaria parasites: evidence for receptor heterogeneity and two receptors 总被引:19,自引:0,他引:19
Plasmodium falciparum malaria parasites with different capabilities of invading sialic acid-deficient erythrocytes were identified. Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase-treated and Tn erythrocytes twice as efficiently as Thai-2 parasites cultured in normal erythrocytes and seven to ten times more efficiently than a cloned line of Camp parasites cultured in normal erythrocytes. All three parasite lines required sialic acid for optimal invasion, but Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase- treated erythrocytes with 45% efficiency whereas Camp parasites invaded neuraminidase-treated erythrocytes with less than 10% efficiency. P falciparum malaria parasites probably possess two receptors: one that binds to a sialic acid-dependent ligand and another that binds to a sialic acid-independent ligand. Parasites may differ in the quantity or affinity of their receptors for the sialic acid-independent ligand. 相似文献