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81.
82.
Although sarcoidosis is predominantly a pulmonary disorder, it often produces disease in the head and neck. For this reason, otolaryngologists should be comfortable in evaluating and treating the disease. The diagnosis of sarcoidosis often can be made with a biopsy of conjunctival or oral mucosa, even when disease manifestations are not apparent in those parts of the body. In a case of sarcoidosis involving the nose, a 54-year-old black man had a proliferation of small lumps on the tip of his nose. For many years, he had had daily epistaxis, anosmia and severe difficulty breathing through this nose. The bridge of his nose was deformed, and he had a large anterior septal perforation. Physical examination revealed palpable bilateral cervical lymphadenopathy. Laboratory test results were, for the most part, normal; however, fine-needle aspiration of one of the cervical lymph nodes showed multiple epithelioid granulomas with interspersed lymphocyte, and an incisional biopsy of the nasal tissue was highly suggestive of sarcoidosis. Unenhanced computed tomography also revealed widespread nasal inflammation and an abnormal soft tissue mass anterior to the maxilla consistent with chronic osteomyelitis. The patient's condition dramatically improved following treatment with oral prednisone; however, he considered undergoing reconstructive surgery for the noticeable nasal septal deformity. 相似文献
83.
A carnivore, the ferret possesses a vomeronasal organ--accessory olfactory bulb (VNO-AOB) projection to the hypothalamus; however, little is known about its function. Pheromones in soiled bedding from estrous female ferrets or an artificial peppermint odor significantly augmented nuclear Fos protein immunoreactivity (Fos-IR), a marker of neural activation, in several main olfactory bulb (MOB) sites but not in the AOB of gonadectomized male and females. Testosterone propionate (TP) significantly augmented the MOB's neuronal Fos responses to estrous females' pheromones, but not to peppermint. Estrous odors, but not peppermint, also augmented neuronal Fos-IR in the medial preoptic area (mPOA) of female, but not male, subjects. Pheromones in soiled bedding from breeding male ferrets significantly augmented neuronal Fos-IR in the MOB and in the medial amygdala of gonadectomized, TP-treated male and female subjects. Again, male pheromones failed to influence neuronal Fos-IR in the AOB of either sex, and only females showed significant increases in neuronal Fos-IR in the lateral aspect of the ventromedial nucleus and mPOA. These results point to an essential role among higher mammals of the main olfactory epithelium-MOB projection to the hypothalamus in detecting and processing pheromones. Gonadectomized ferrets showed significant increases in sniffing behavior when placed on either female or male bedding. This occurred regardless of whether they had received TP or oil vehicle, suggesting that testosterone's facilitation of neuronal Fos responses to estrous females' odors in the MOB of both sexes cannot be attributed to increased scent gathering. Androgen receptor-IR was present in the MOB granule cell layer of male and female ferrets, raising the possibility that testosterone acts directly on these cells to augment their responsiveness to pheromones. 相似文献
84.
JE Ruiz JY Kwak L Baum A Gilman-Sachs KD Beaman YB Kim AE Beer 《Canadian Metallurgical Quarterly》1996,31(1-2):125-141
Intravenous immunoglobulin (IVIg) has been used to treat women with recurrent spontaneous abortion (RSA), particularly for women with elevated natural killer (NK) cells. We investigated the effect of IVIg on peripheral blood NK cell activity in vitro in women with RSA. 51Cr-release assays using K562 in the presence of varying concentrations of IVIg were performed using PBL from 16 women with RSA. Antibody dependent cellular cytotoxicity (ADCC) was evaluated using Daudi cells. Effectors and targets were preincubated with IVIg. Binding of IVIg to K562 and Daudi was evaluated by flow cytometry. The effect of K562 absorbed IVIg on NK activity was compared to that of non-absorbed IVIg. NK cytotoxicity and ADCC in the presence of F(ab')2 fragments were compared with those in the presence of intact IVIg. IVIg produced a significant, dose dependent inhibition of NK activity in vitro. Inhibition of NK activity occurred when effectors but not targets were preincubated with IVIg. IVIg binds to K562 and Daudi. IVIg increased ADCC when targets but not effectors were incubated with IVIg. K562 absorbed IVIg produced more inhibition of NK cytotoxicity than non-absorbed IVIg. Suppression of NK cytotoxicity by F(ab')2 was as effective as that of IVIg. However, F(ab')2 did not increase ADCC. IVIg effectively reduces peripheral blood NK cytotoxicity in vitro. Inhibition of NK cytotoxicity is mediated at the effector cell level through the antigen binding portion of the immunoglobulins. Women with RSA and elevated NK cells may benefit from IVIg treatment. 相似文献
85.
Translated from Izmeritel'naya Tekhnika, No. 2, pp. 51–53, February, 1991. 相似文献
86.
Leigh Irene W.; Smith I. Leon; Bebeau Muriel J.; Lichtenberg James W.; Nelson Paul D.; Portnoy Sanford; Rubin Nancy J.; Kaslow Nadine J. 《Canadian Metallurgical Quarterly》2007,38(5):463
This article describes characteristics of alternative assessment models deployed in the measurement of professional competencies across the professional life span based on the work of the American Psychological Association Task Force on the Assessment of Competence in Professional Psychology. Assessments of knowledge, decision making, performance and personal attributes, as well as integrated practice-based skills and tasks are described and compared on the basis of their validity, feasibility and practicality, fidelity, and relevance at difference stages of professional development. It is acknowledged that no single assessment can evaluate all competencies and that assessments can be combined in complementary ways. Assessments deployed in the nursing, dental, and medical professions are reviewed and contrasted with current practices in psychology. At the licensure level, differences in the assessments deployed among the 4 healthcare professions are described, and their candidate fees and number of candidates assessed annually are documented. Ideas for developing new assessments in psychology are discussed on the basis of the needs and financial resources available to psychology and the experiences of other healthcare professions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
88.
In contrast to the many neural studies into the mechanisms of sleep onset and maintenance, few studies have focused specifically on awakening from sleep. However, the abrupt electrographic changes and large brief cardio-respiratory activation at awakening suggest that a distinct, transiently aroused, awake state may exist compared to later wakefulness. To test this hypothesis we utilized the acoustic startle reflex, a standard un-conditioned reflex elicited by a sudden loud noise. This reflex is modulated under specific conditions, one being a diminution of startle when a quieter pre-stimulus is presented immediately before the loud stimulus. This pre-pulse inhibition (PPI) is used as a measure of sensorimotor gating, with smaller PPI indicating less filtering of sensory inputs and increased responsiveness to external stimuli. Eight rats with electrodes for recording sleep-wake state were studied. An accelerometer measured startle responses. The startle reflex was elicited by 115 dB, 40 ms tones. PPI was produced by 74 dB, 20 ms tones preceding the 115 dB tone by 100 ms. Responses within 100 ms were measured. Stimuli were applied either 3-10 s after spontaneous awakenings, or in established wakefulness (> 30 s). Responses to the startle stimuli alone were similar in the different awake states (P = 0.821). However, PPI was smaller at awakening from non-REM sleep compared to established wakefulness (45.4 +/- 7.5% vs. 74.3 +/- 6.1%, P = 0.0002). PPI after awakening from REM sleep (52.8 +/- 17.9%) was not significantly different than established wakefulness (P = 0.297). Reduced PPI of the startle reflex at awakening from non-REM sleep supports the hypothesis that wakefulness immediately after spontaneous sleep episodes is neurophysiologically distinct from later wakefulness and associated with reduced gating of motor responses to sensory inputs. Spontaneous activation of this distinct, transiently aroused, state upon awakening may serve a protective function, preparing an animal to respond immediately to potentially threatening stimuli. 相似文献
89.
90.
Lindmark B. Lundgren S. Sanford J.R. Beckman C. 《Antennas and Propagation, IEEE Transactions on》1998,46(6):758-763
A novel dual-polarized antenna array designed for a spatial division multiple access (SDMA) system working in the 1850-1990-MHz band is designed and built. The antenna is designed to have similar element patterns, and measurements of S-parameters and radiation patterns are presented. The array signal processing performance of the array using all elements and with no compensation for mutual coupling or differences in element patterns is studied through direction-of-arrival (DOA) estimation using total least squares estimation of signal parameters via rotational invariance techniques (TLS-ESPRIT). The results show that the accuracy of the DOA estimates is quite acceptable for wireless communication applications 相似文献