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排序方式: 共有579条查询结果,搜索用时 15 毫秒
91.
Trond Nordseth Daniel Bergum Dana P. Edelson Theresa M. Olasveengen Trygve Eftestøl Rune Wiseth Benjamin S. Abella Eirik Skogvoll 《Resuscitation》2013
Background
When providing advanced life support (ALS) in cardiac arrest, the patient may alternate between four clinical states: ventricular fibrillation/tachycardia (VF/VT), pulseless electrical activity (PEA), asystole, and return of spontaneous circulation (ROSC). At the end of the resuscitation efforts, either death has been declared or sustained ROSC has been obtained. The aim of this study was to describe and analyze the clinical state transitions during ALS among patients experiencing in-hospital cardiac arrest.Methods and results
The defibrillator files from 311 in-hospital cardiac arrests at the University of Chicago Hospital (IL, USA) and St. Olav University Hospital (Trondheim, Norway) were analyzed (clinicaltrials.gov: NCT00920244). The transitions between clinical states were annotated along the time axis and visualized as plots of the state prevalence according to time. The cumulative intensity of the state transitions was estimated by the Nelson–Aalen estimator for each type of state transition, and for the intensities of overall state transitions. Between 70% and 90% of patients who eventually obtained sustained ROSC had progressed to ROSC by approximately 15–20 min of ALS, depending on the initial rhythm. Patients behaving unstably after this time period, i.e., alternating between ROSC, VF/VT and PEA, had a high risk of ultimately being declared dead.Conclusions
We provide an overall picture of the intensities and patterns of clinical state transitions during in-hospital ALS. The majority of patients who obtained sustained ROSC obtained this state and stabilized within the first 15–20 min of ALS. Those who continued to behave unstably after this time point had a high risk of ultimately being declared dead. 相似文献92.
The aim of this study was to describe sources of information, as well as barriers and facilitators to the use of research during consultations by public health nurses concerning childhood vaccinations. The study was conducted using semi-structured focus group interviews in a grounded theory approach. Overall 16 public health nurses participated into three focus groups conducted in 2008. We found that the public health nurses' most important sources of information were the National guidelines and other information issued by the National Institute of Public Health. Although they argued that research was important for being able to base practice on solid information, for their own professional development and for meeting parents' demands, they were reluctant to search for such information themselves. This was explained by beliefs about their own role, limited critical appraisal skills and perceived capacity. We conclude with that insight into how knowledge is produced and how to obtain such information is not only a necessity for good quality health care and professional development, but is also a way to address challenges such as time, overload of information and the ability to answer questions parents may have. More emphasis should be given to empowering public health nurses so they can find and critically appraise research, and this should be an integrated part of practice. 相似文献
93.
Osteoclasts promote the formation of hematopoietic stem cell niches in the bone marrow 总被引:1,自引:0,他引:1
Mansour A Abou-Ezzi G Sitnicka E Jacobsen SE Wakkach A Blin-Wakkach C 《The Journal of experimental medicine》2012,209(3):537-549
Formation of the hematopoietic stem cell (HSC) niche in bone marrow (BM) is tightly associated with endochondral ossification, but little is known about the mechanisms involved. We used the oc/oc mouse, a mouse model with impaired endochondral ossification caused by a loss of osteoclast (OCL) activity, to investigate the role of osteoblasts (OBLs) and OCLs in the HSC niche formation. The absence of OCL activity resulted in a defective HSC niche associated with an increased proportion of mesenchymal progenitors but reduced osteoblastic differentiation, leading to impaired HSC homing to the BM. Restoration of OCL activity reversed the defect in HSC niche formation. Our data demonstrate that OBLs are required for establishing HSC niches and that osteoblastic development is induced by OCLs. These findings broaden our knowledge of the HSC niche formation, which is critical for understanding normal and pathological hematopoiesis. 相似文献
94.
A Barratt-Due SE Pischke OL Brekke EB Thorgersen EW Nielsen T Espevik M Huber-Lang TE Mollnes 《Immunobiology》2012,217(11):1047-1056
Attenuating the sepsis-induced systemic inflammatory response, with subsequent homeostatic imbalance, has for years been one of the main tasks in sepsis related research. Complement and the TLR family constitute two important upstream sensor and effector-systems of innate immunity. Although they act as partly independent branches of pattern recognition, recent evidence indicate a considerable cross-talk implying that they can either compensate, synergize or antagonize each other. Combined inhibition of these pathways is therefore a particularly interesting approach with a profound anti-inflammatory potential. In previous preclinical studies, we demonstrated that targeting the key molecules C3 or C5 of complement and CD14 of the TLR family had a vast anti-inflammatory effect on Gram-negative bacteria-induced inflammation and sepsis. In this review, we elucidate the significance of these key molecules as important targets for intervention in sepsis and systemic inflammatory response syndrome. Finally, we argue that a combined inhibition of complement and CD14 represent a potential general treatment regimen, beyond the limit of sepsis, including non-infectious systemic inflammation and ischemia reperfusion injury. 相似文献
95.
Dag Henrik Reikvam Muriel Derrien Rejoanoul Islam Alexander Erofeev Vedrana Grcic Anders Sandvik Peter Gaustad Leonardo A. Meza‐Zepeda Frode L. Jahnsen Hauke Smidt Finn‐Eirik Johansen 《European journal of immunology》2012,42(11):2959-2970
Innate and adaptive mucosal defense mechanisms ensure a homeostatic relationship with the large and complex mutualistic gut microbiota. Dimeric IgA and pentameric IgM are transported across the intestinal epithelium via the epithelial polymeric Ig receptor (pIgR) and provide a significant portion of the first line of natural or adaptive antibody‐mediated immune defense of the intestinal mucosa. We found that colonic epithelial cells from pIgR KO mice differentially expressed (more than twofold change) more than 200 genes compared with cells from WT mice, and upregulated the expression of antimicrobial peptides in a commensal‐dependent manner. Detailed profiling of microbial communities based on 16S rRNA genes revealed differences in the commensal microbiota between pIgR KO and WT mice. Furthermore, we found that pIgR KO mice showed increased susceptibility to dextran sulfate sodium‐induced colitis, and that this was driven by their conventional intestinal microbiota. Thus, in the absence of pIgR, the stability of the commensal microbiota is disturbed, gut homeostasis is compromised, and the outcome of colitis is significantly worsened. 相似文献
96.
97.
Ramm-Pettersen J Berg-Johnsen J Hol PK Roy S Bollerslev J Schreiner T Helseth E 《Acta neurochirurgica》2011,153(7):1367-1373
Background
During trans-sphenoidal microsurgical resection of pituitary adenomas, the extent of resection may be difficult to assess, especially when extensive suprasellar and parasellar growth has occurred. In this prospective study, we investigated whether intra-operative magnetic resonance imaging (iMRI) can facilitate tumour resection. 相似文献98.
99.
The neonatal intensive care unit (NICU) is an environment that provides premature and fragile infants with health provisions needed to make a complete recovery. Premature infants are often born before their auditory systems have had an opportunity to fully mature. Research has shown that the ambient acoustic environment in the NICU exceeds the maximum noise level recommended by the American Academy of Pediatrics, even after measures have been taken to decrease noise levels. The purpose of this study is to evaluate noise levels inside an Ohmeda Medical Giraffe? OmniBed?, the natural attenuation of the incubator, and the effects of modifications on attenuation and reverberation within the Giraffe TM OmniBed?. The normal operation of the Giraffe? OmniBed? is 41.7 dBA which indicates a lower noise of operation than previous studies. The Giraffe? OmniBed? naturally attenuates 12 dBA. Leaving an access latch or portal door open causes a statistically significant (P=.001) increase in sound within the bassinet. All modifications in the no-noise and the noise conditions showed a statistically significant (P=.001) drop in L(eq) when compared to baseline. 相似文献