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1.
Eimeria (s. l.) vanasi n. sp. is described from the intestine of a variety of cichlids in Israel and South Africa. Merogony and gamogony stages are both intra- and epiepithelial, Sporogony is exogenous with young zygotes being released from the fish in the faeces. Fully developed sporocysts are ellipsoid and apparently lacking both a Stieda body (characteristic of Eimeria s. st. and Epieimeria species) and a suture line (characteristic of Goussia species). In view of the present controversial generic status of piscine coccidia, the species is tentatively designated as Eimeria (s. l.) vanasi n. sp. (Eimeriidae, Apicomplexa, Protozoa). 相似文献
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Michael Friedman MD Darius Bliznikas MD Ramakrishnan Vidyasagar MBBS MS Roee Landsberg MD 《Operative Techniques in Otolaryngology》2004,15(1):23
Endoscopic frontal sinus surgery is still considered difficult, risky to perform, and likely to result in a high failure rate. We have previously reported on our technique of endoscopic frontal sinus surgery, stressing the importance of identification and preservation of natural outflow tract. Our study of frontal sinus anatomy shows that the mean frontal ostium anterior—posterior and transverse dimensions are 7.22 ± 2.78 mm and 8.92 ± 2.95 mm, respectively; therefore, dissection of obstructive structures in frontal recess leads to a wide opening of frontal sinus outflow. A key surgical landmark in our technique is the superior attachment of the uncinate process. This article provides an update of the surgical anatomy of the frontal recess region and our surgical technique, as well as a discussion of our approach to frontal sinus revision surgery. 相似文献
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Heather G. Allore PhD Keith S. Goldfeld DrPH Roee Gutman PhD Fan Li PhD Joan K. Monin PhD Monica Taljaard PhD Thomas G. Travison PhD 《Journal of the American Geriatrics Society》2020,68(Z2):S68-S73
There is overwhelming need for nonpharmacological interventions to improve the health and well-being of people living with dementia (PLWD). The National Institute on Aging Imbedded Pragmatic Alzheimer's Disease (AD) and AD-Related Dementias Clinical Trials (IMPACT) Collaboratory supports clinical trials of such interventions embedded in healthcare systems. The embedded pragmatic clinical trial (ePCT) is ideally suited to testing the effectiveness of complex interventions in vulnerable populations at the point of care. These trials, however, are complex to conduct and interpret, and face challenges in efficiency (i.e., statistical power) and reproducibility. In addition, trials conducted among PLWD present specific statistical challenges, including difficulty in outcomes ascertainment from PLWD, necessitating reliance on reports by caregivers, and heterogeneity in measurements across different settings or populations. These and other challenges undercut the reliability of measurement, the feasibility of capturing outcomes using pragmatic designs, and the ability to validly estimate interventions' effectiveness in real-world settings. To address these challenges, the IMPACT Collaboratory has convened a Design and Statistics Core, the goals of which are: to support the design and conduct of ePCTs directed toward PLWD and their caregivers; to develop guidance for conducting embedded trials in this population; and to educate quantitative and clinical scientists in the design, conduct, and analysis of these trials. In this article, we discuss some of the contemporary methodological challenges in this area and develop a set of research priorities the Design and Statistics Core will undertake to meet these goals. J Am Geriatr Soc 68:S68–S73, 2020 . 相似文献
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Shani Golan Igal Leibovitch Roee Landsberg 《European archives of oto-rhino-laryngology》2014,271(11):3053-3058
The objective of this study is to describe a series of patients with different pathologies mimicking nasolacrimal duct obstruction (NLDO), diagnosed with the use of a computed tomography (CT) scan prior to a scheduled endoscopic dacryocystorhinostomy (DCR). This study is a retrospective report. We reviewed the medical records of 47 consecutive patients (57 sides) with long-standing epiphora between 2007 and 2012. All patients were referred to our tertiary Medical Center with a diagnosis of NLDO and were expected to undergo endoscopic dacryocystorhinostomy (DCR). They all underwent routine sinus CT scan prior to surgery. All scans, as well as the demographic and medical characteristics of these patients were reviewed. Of all 47 patients enrolled, in 4 patients (7 % of all sides), unexpected pathologies, other than nasolacrimal system distention, inflammation or infection were identified preoperatively. These included squamous cell carcinoma of the lacrimal sac and nasolacrimal duct, rhinoscleroma at Hasner’s valve region, a compressing ethmoidal mucocele and a case of dacryocystocele. These unusual pathologies mandated a different management and surgical approach. In all four cases, a preoperative CT scan helped in identifying the pathology and in localizing the lacrimal apparatus in relation to the paranasal sinuses. Different nasal, paranasal and lacrimal pathologies may mimic primary acquired NLDO. A high index of suspicion, a thorough clinical evaluation and utilizing preoperative imaging may lead to an alteration of patient management and to a completely different surgical approach. 相似文献
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Metabolic studies in human obesity during overnutrition and undernutrition: thermogenic and hormonal responses to norepinephrine 总被引:1,自引:0,他引:1
H L Katzeff M O'Connell E S Horton E Danforth J B Young L Landsberg 《Metabolism: clinical and experimental》1986,35(2):166-175
Overfeeding increases the thermogenic response of norepinephrine (NE) in normal but not in certain genetically obese rodents. It has been suggested that human obesity may be associated with a similar thermogenic defect. To determine whether there are differences in the thermogenic sensitivity to NE in human obesity, energy expenditure in response to graded infusions of NE (0.05, 0.10, 0.15, 0.20 micrograms/min/kg fat-free mass) was measured in six lean and six obese subjects (9.5 +/- 1.8 v 36.3 +/- 3.8% body fat P less than 0.005). Resting metabolic rate (RMR), thermogenic response to NE, and thermogenic response to exercise were measured during weight maintenance and during the third week of feeding 1000 extra Kcal/d in the lean and obese subjects. These components of energy expenditure were also measured in the obese subjects during the third week of a 589 Kcal/d diet. Resting metabolic rate increased during overfeeding in lean (6.6%, P less than 0.05) but not in the obese subjects (2.7%, P = NS) and fell during underfeeding in the obese (-9.1%, P less than 0.02). There was a logarithmic increment above baseline in VO2 v plasma NE concentration during the NE infusions (r = 0.75, P less than 0.005) in lean subjects which was unaltered by overfeeding. The obese exhibited equivalent VO2 responses to NE to that measured in the lean. Supine plasma NE concentrations were lower but metabolic clearance rates (MCR) of NE were similar in the obese compared to lean subjects during both weight maintenance and overfeeding. Overfeeding minimally increased plasma concentration but not MCR of NE in both groups. The thermogenic response to exercise was similar in the lean and obese subjects and was unaltered by overfeeding or underfeeding. The increments in plasma glycerol and free fatty acid in response to the NE infusions were proportional to the total fat mass of each individual and were greater in the obese subjects. Overfeeding partially suppressed the lipolytic response to NE in both groups and underfeeding increased the lipolytic response in the obese. There are no differences in thermogenic responses to NE in human obesity to account for excessive fat deposition. Overfeeding does not increase the thermogenetic responses to NE in humans as has been reported in small mammals. 相似文献
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Roee Admon Dmitry Leykin Gad Lubin Veronika Engert Julie Andrews Jens Pruessner Talma Hendler 《Human brain mapping》2013,34(11):2808-2816
Previous studies have shown that people who develop psychopathology such as posttraumatic stress disorder (PTSD) following stress exposure are characterized by reduced hippocampal (HC) volume and impaired HC functional connectivity with the ventromedial prefrontal cortex (vmPFC). Nevertheless, the exact interrelationship between reduced HC volume and HC‐vmPFC connectivity deficits in the context of stress has yet to be established. Furthermore, it is still not clear whether such neural abnormalities are stress induced or precursors for vulnerability. In this study, we combined measurements of MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI) to prospectively study 33 a priori healthy Israeli soldiers both pre‐ and post‐exposure to stress during their military service. Thus, we were able to assess the contributions of structural and functional features of the HC and its connectivity to the onset and progression of maladaptive response to stress (i.e., increased PTSD symptoms post‐exposure). We found that soldiers with decreased HC volume following military service (i.e., post‐exposure) displayed more PTSD‐related symptoms post‐exposure as well as reduced HC‐vmPFC functional and structural connectivity post‐exposure, compared to soldiers with increased HC volume following military service. In contrast, initial smaller HC volume pre‐exposure did not have an effect on any of these factors. Our results therefore suggest that reduction in HC volume and connectivity with the vmPFC together mark a maladaptive response to stressful military service. As stress‐induced HC volume reductions were previously shown to be reversible, these localized biological markers may carry valuable therapeutic potential. Hum Brain Mapp 34:2808–2816, 2013. © 2012 Wiley Periodicals, Inc. 相似文献