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This research applied the life table technique to nursing personnel data in two types of hospitals to illustrate how administrators can examine patterns of continued employment. Although a large proportion of nurses were short-stay employees, the teaching hospital was found to have a higher retention rate than the community hospital corporation. The retention patterns are examined by personal and professional characteristics, as well as by reason for termination. Implications of our findings are discussed with respect to policy concerns related to hiring, retention, productivity, and staff development. 相似文献
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CSF rhinorrhea is called spontaneous if it is due neither to a trauma, nor an intracranial tumour or a congenital malformation. Spontaneous CSF rhinorrhea is extremely rare: the fistula is usually found in the roof of the ethmoid sinus, less often in the walls of the sphenoid sinus. There is a striking prevalence of female patients. We describe a female patient who showed spontaneous CSF rhinorrhea from a leak in the anterior roof of the sphenoid sinus. The possible aetiology, diagnostic measures and therapy are discussed. Areas of reduced resistance in the anterior skull base may be congenital, or may be acquired due to later focal atrophy. The diagnosis of CSF rhinorrhea can be established by the glucose test, isotope scanning, immunoelectrophoresis and fluorescence endoscopy. The most reliable methods of distinguishing between a traumatic or neoplastic lesion and a spontaneous CSF rhinorrhea are high-resolution computed tomography (CT) and magnetic resonance tomography. High-resolution CT is also the best method for localization of the bony defect. Elevated intracranial pressure must be ruled out carefully. The treatment of choice is closure of the fistula, preferably by the nasal surgeon, using either the endonasal-transseptal, the endonasal-transethmoidal or the paranasal-transethmoidal approach in order to preserve olfaction and to avoid the risk of a frontal lobe lesion which is a complication of the neurosurgical approach. Interposition of a fascial or dural graft is considered to be an important technical detail for achieving a secure closure of the fistula; packing can be avoided by additional sealing of the patch with fibrinogen glue. 相似文献
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There are several urologic disorders which also involve the eye and orbit. We have compiled examples of these and reviewed the literature. Metastasis from genitourinary malignancy (including neuroblastoma), Wilms tumor, Reiter syndrome, tuberous sclerosis, von Hippel-Lindau disease, and oxalosis may all have ophthalmologic manifestations. Urologists need to be aware of these and obtain appropriate consultation in order to fully care for patients with these diseases. 相似文献
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Takuya Watanabe Keiko Takahashi Tomoko Kanome Shigeki Hongo Akira Miyazaki Shinji Koba Takashi Katagiri Rajbabu Pakara Claude R Benedict 《Hypertension research》2006,29(10):821-831
Human urotensin-II (U-II) is the most potent vasoactive peptide identified to date, and may be involved in hypertension and atherosclerosis. We investigated the effects of the interactions between U-II or other vasoactive agents and mildly oxidized low-density lipoprotein (mox-LDL) or hydrogen peroxide (H2O2) on the induction of vascular smooth muscle cell (VSMC) proliferation. Growth-arrested rabbit VSMCs were incubated with vasoactive agents (U-II, endothelin-1, angiotensin-II, serotonin, or thromboxane-A2) in the presence or absence of mox-LDL or H2O2. [3H]Thymidine incorporation into DNA was measured as an index of VSMC proliferation. On interaction with mox-LDL or H2O2, U-II induced the greatest increase in [3H]thymidine incorporation among these vasoactive agents. A low concentration of U-II (10 nmol/l) enhanced the potential mitogenic effect of low concentrations of mox-LDL (120 to 337%) and H2O2 (177 to 226%). U-II at 50 nmol/l showed the maximal mitogenic effect (161%), which was abolished by G protein inactivator (GDP-beta-S), c-Src tyrosine kinase inhibitor (radicicol), protein kinase C (PKC) inhibitor (Ro31-8220), extracellular signal-regulated kinase (ERK) kinase inhibitor (PD98059), or Rho kinase inhibitor (Y27632). Mox-LDL at 5 microg/ml showed the maximal mitogenic effect (211%), which was inhibited by free radical scavenger (catalase), intracellular and extracellular antioxidants (N-acetylcysteine and probucol), nicotinamide adenine dinucleotide phosphate oxidase inhibitor (diphenylene iodonium), or c-Jun N-terminal kinase (JNK) inhibitor (SP600125). These results suggested that U-II acts in synergy with mox-LDL in inducing VSMC DNA synthesis at the highest rate among these vasoactive agents. Activation of the G protein/c-Src/PKC/ERK and Rho kinase pathways by U-II together with the redox-sensitive JNK pathway by mox-LDL may explain the synergistic interaction between these agents. 相似文献
6.
Elizabeth R Seaquist Wei Chen Luke E Benedict Kamil Ugurbil Jae-Hwan Kwag Xiao-Hong Zhu Charles A Nelson 《Journal of cerebral blood flow and metabolism》2007,27(1):154-160
Functional magnetic resonance imaging (fMRI) based on blood oxygen level-dependent (BOLD) contrast has become an invaluable tool in the assessment of in vivo neuronal activation. Quantification of the BOLD response is determined by the hemodynamic and metabolic changes that occur in response to brain stimulation. However, these changes may vary by changes in insulin, a hormone known to be vasoactive in some tissues. To determine if insulin has an effect on fMRI, we measured the BOLD response to a visual stimulus in five normal volunteers in which insulin was first suppressed and then brought to a high physiological concentration. In addition, we also examined the effect of insulin on activation of the visual cortex as measured by the visual-evoked potential (VEP). We found that the BOLD response measured in the presence of insulin (serum insulin=236+/-29 pmol/L) was significantly lower (P<0.001) than that measured in its absence (serum insulin=8+/-2 pmol/L). Insulin was without effect on P100 amplitude or latency acquired in the presence or absence of insulin in 28 subjects using the same stimulus as that used for the fMRI experiments. Our observations suggest that insulin may have effects on cerebral blood flow and/or metabolism that affect the BOLD signal that are independent of its effects on neuronal activation identified by event related potentials (ERP). These findings highlight the complexity that must be considered when interpreting differences in fMRI responses between groups of subjects that differ in insulin concentration and/or insulin sensitivity. 相似文献
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Leo Andrew Benedict Joseph A. Sujka Justin A. Sobrino Hanna Alemayehu Pablo Aguayo Richard Hendrickson Shawn D. St. Peter Tolulope A. Oyetunji 《Journal of pediatric surgery》2021,56(4):663-667
PurposePrevious reports in the literature demonstrate racial and ethnic disparities for children diagnosed with acute appendicitis, with minorities experiencing worse outcomes. At our institution, we have developed an evidence based patient driven protocol for children following laparoscopic appendectomy. However, the influence of such protocol on mitigating racial and ethnic disparities in outcomes remains unknown. The purpose of our study is to assess the impact of our protocol by evaluating the influence of race and ethnicity on surgical outcomes among children treated for acute appendicitis.Material and methodsA retrospective review of prospectively collected data was conducted. Children undergoing a laparoscopic appendectomy at our freestanding children's hospital between December 2015 and July 2017 were included. Demographic data, post-operative length of stay, same day discharge rates and hospital readmission rates were abstracted from patient medical records. Patients were classified by their race and ethnic background. Comparative analysis was performed in STATA with a p value < .05 determined as significant.ResultsA total of 786 children were included, with the majority being either White (70%, n = 547), Black (8%, n = 62) or Hispanic (17%, n = 133); 569 patients (72%) were found to have non-perforated appendicitis. There was no statistically significant difference in the rates of same day discharge among White, Black or Hispanic children respectively (88% vs. 77% vs. 86%, p = .126). Of the 217 children with perforated appendicitis, Hispanic children had increased rates of perforation (41%, n = 55) compared to White and Black children respectively (23%, n = 128 and 29%, n = 18, p = .001). However, average post-operative length of stay were similar among White, Black and Hispanic children (96 h vs. 95 h vs. 98 h, p = .015). On multivariate analysis, the only significant risk factor for an elevated post-operative length of stay was the presence of a perforation.ConclusionOur evidence based patient driven protocol effectively mitigates racial and ethnic disparities found in children with acute appendicitis. Further prospective investigation into the role of such patient-driven protocols to mitigate healthcare disparities is warranted.Levels of EvidenceTherapeutic study; Level 3. 相似文献
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