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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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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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HDAC6 inhibition results in tau acetylation and modulates tau phosphorylation and degradation in oligodendrocytes 下载免费PDF全文
Histone deacetylase 6 (HDAC6) is a unique member of the HDAC family. It is localized within the cytoplasm and has unique substrate specificities for nonhistone proteins, such as α‐tubulin. Furthermore, it plays a major role in protein aggregate formation and recently was demonstrated to interact with the microtubule associated protein tau and tau was identified as a possible substrate for HDAC6 in neurons. This study was undertaken to investigate whether HDAC6 is present in oligodendrocytes and whether it is involved in tubulin and tau acetylation in these cells. We show for the first time that HDAC6 is expressed in cultured rat brain oligodendrocytes. Its inhibition by the specific HDAC6 inhibitor tubastatin A (TST) leads to morphological alterations, microtubule bundling, and tubulin acetylation, and changes in tau‐isoform expression and phosphorylation. Furthermore, the microtubule binding activity of tau was reduced. Using the oligodendroglial cell lines OLN‐t40 and OLN‐t44, which were genetically engineered to express either the longest human tau isoform with four microtubule binding repeats (4R‐tau), or the shortest tau isoform with three repeats (3R‐tau), respectively, we demonstrate that tau is acetylated by HDAC6 within the 4R‐binding domain. Tau acetylation reduced its turnover rate and acetylated tau was degraded slower in these cells. TST and shRNA‐mediated knockdown of HDAC6 in oligodendroglia cells caused an increase in pathological hyperphosphorylated tau detectable with the 12E8 antibody. Hence HDAC6 and dysregulation of the deacetylation and acetylation process in oligodendrocytes may contribute to diseases with oligodendroglial pathology. GLIA 2014;62:535–547 相似文献
8.
BACKGROUND: Therapeutic paratracheal neck dissection for patients with papillary carcinoma of the thyroid is standard treatment. Its use as an elective procedure is controversial. METHODS: Thirty-seven patients with papillary carcinoma of the thyroid and evidence of positive adenopathy at levels II-V underwent selective neck dissection and elective/therapeutic paratracheal neck dissection. Results of preoperative ultrasonography of the neck were compared with the dissection specimens. RESULTS: Morbidity of the surgical procedure was minimal (1 permanent hypocalcemia). All specimens showed metastases from papillary thyroid carcinoma: 100% (37/37) in the jugular chain of lymphatics and 83.7% (31/37) in the paratracheal region. The rate of occult (negative physical examination and ultrasonography) metastases in the paratracheal region in the presence of metastases in the ipsilateral jugular chain was 83.3% (20/24). CONCLUSION: The high rate of occult metastases in the paratracheal region and the low rate of surgical morbidity speak in favor of elective paratracheal neck dissection in patients with metastatic papillary carcinoma of the thyroid. 相似文献
9.
Aim of the study: Is it possible to use the Internet as a secure media for transport of telemedicine? Which risks exist for routine use? In this article state of the art methods of security were analysed. Telemedicine in the Internet has severe risks, because patient data and hospital data of a secure Intranet can be manipulated by connecting it to the Web. Conclusions: Establishing of a firewall and the introduction of HPC (Health Professional Card) are minimizing the risk of un-authorized access to the hospital server. HPC allows good safety with digital signature and authentication of host and client of medical data. For secure e-mail PGP (Pretty Good Privacy) is easy to use as a standard protocol. Planning all activities exactly as well as following legal regulations are important requisites for reduction of safety risks in Internet. 相似文献
10.
Catecholamines and hyperthyroidism. 总被引:2,自引:0,他引:2
L Landsberg 《Clinics in endocrinology and metabolism》1977,6(3):697-718