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111.
112.
Lauren E. Yue Sarah L. Spaulding Fred M. Baik Azita Khorsandi Margaret Brandwein-Weber Mark L. Urken 《Head and neck pathology》2021,15(1):323
Multifocal cystic oncocytosis (MCO) is a rare, benign process accounting for approximately 0.1% of salivary gland lesions. Salivary oncocytosis is characterized by multiple unencapsulated solid nodules of oncocytic cells derived from transformed striated ducts. MCO is a variant of salivary oncocytosis which manifests as cystically dilated striated ducts. It is difficult to obtain a definitive preoperative diagnosis of MCO; therefore, these lesions are commonly treated with surgery. We report the unique case of a 66-year-old male who previously underwent a superficial left parotidectomy for a pleomorphic adenoma. Four years later, he presented with clinical and radiographic suspicion of a multifocal recurrent pleomorphic adenoma. The patient subsequently underwent a revision parotidectomy. However, final pathology confirmed a diagnosis of MCO. Although MCO is commonly treated with surgery due to lack of a definitive preoperative diagnosis, surgery is unnecessary outside of diagnostic, functional or cosmetic considerations. Thus, if a patient with parotid oncocytosis treated by superficial parotidectomy develops disease re-manifestation in the residual deep lobe, further surgery is not indicated. There is no risk of malignant progression in this process. We report on this unusual entity as it may mimic salivary malignancy or, as in this case, recurrence of benign disease. 相似文献
113.
114.
Foxp3 and natural regulatory T cells: key to a cell lineage? 总被引:22,自引:0,他引:22
Ramsdell F 《Immunity》2003,19(2):165-168
115.
Finkelman FD Rothenberg ME Brandt EB Morris SC Strait RT 《The Journal of allergy and clinical immunology》2005,115(3):449-57; quiz 458
Studies with murine models demonstrate 2 pathways of systemic anaphylaxis: one mediated by IgE, Fc epsilonRI, mast cells, histamine, and platelet-activating factor (PAF), and the other mediated by IgG, Fc gammaRIII, macrophages, and PAF. The former pathway requires much less antibody and antigen than the latter. As a result, IgG antibody can block IgE-mediated anaphylaxis induced by small quantities of antigen without mediating Fc gammaRIII-dependent anaphylaxis. The IgE pathway is most likely responsible for most human anaphylaxis, which generally involves small amounts of antibody and antigen; similarities in the murine and human immune systems suggest that the IgG pathway might mediate disease in persons repeatedly exposed to large quantities of antigen. Mice, like human subjects, can experience IgE/Fc epsilonRI/mast cell-mediated gastrointestinal and systemic anaphylaxis in response to ingested antigen. Gastrointestinal symptoms depend on serotonin and PAF; mediator dependence of systemic symptoms has not been determined. Both local and systemic anaphylaxis induced by ingested antigens might be blocked by IgA and IgG antibodies. IL-4 and IL-13 signaling through the IL-4 receptor alpha chain, in addition to promoting the mastocytosis and IgE antibody production that mediate most human anaphylaxis, exacerbates the effector phase of anaphylaxis by increasing target cell responsiveness to vasoactive mediators. As a result, IL-4 receptor alpha chain antagonists might be particularly effective suppressors of anaphylaxis. 相似文献
116.
Fred Paccaud 《Sozial- und Pr?ventivmedizin》1993,38(5):288-293
Summary For several years now, substantial efforts have been devoted to the development and the implementation of a screening program for breast cancer in the Canton of Vaud. A four-year pilot phase is now starting, involving two regional hospitals with their catchment areas; women over 50 and under 70 years old will be invited to participate in the program. A double view mammography will be made, with a double reading made by the hospital radiologists; a third reading will be made in case of discrepancy between the two first radiologists. Patients classified as positive for screening (e.g., with a suspect radiological image) will be referred to their practitioner for further diagnosis and treatment. The medical and public health background of this program is discussed, more specifically the reasons for developing a screening program, the choice of mammography rather than other tools, and the need to implement screening as an organized program.
Paper presented at a symposium on The Public Health Perspective of Social and Preventive Medicine, in celebration of the 20th anniversary of the Department of Social and Preventive Medicine, University of Berne, 25 June 1992 in Berne. 相似文献
Zusammenfassung Vertreter verschiedener medizinischer Fachgebiete bemühen sich seit einigen Jahren darum, für den Kanton Waadt ein Früherfassungsprogramm für den Brustkrebs auf die Beine zu stellen. In zwei Regionen des Kantons wird nun ein Pilotprojekt gestartet, das sich an die 50 bis 70jährigen Frauen richtet und vier Jahre dauern soll. Angeboten wird eine Mammographie in zwei Ebenen, die von zwei Röntgenologen unabhängig voneinander beurteilt werden wird (kommen die beiden Experten zu unterschiedlichen Beurteilungen, wird eine dritte Meinung eingeholt). Bei einem positiven Befund wird die betroffene Frau dem Hausarzt überwiesen, der die diagnostischen Abklärungen und nötigenfalls die Behandlung einleiten wird. Die medizinischen Grundlagen und der epidemiologische Hintergrund werden dargestellt; speziell erwähnt werden die Gründe für die Entwicklung eines Früherfassungsprogrammes und für die Wahl der Mammographie als Screeningmethode.
Résumé Depuis plusieurs années, un groupe réunissant les compétences de plusieurs disciplines médicales examine les possibilités d'implanter le dépistage du cancer du sein dans le Canton de Vaud. Un projet-pilote d'une durée de 4 ans va démarrer dans deux zones sanitaires du canton, adressé aux femmes âgées entre 50 et 70 ans: il s'agira d'une mammographie à double incidence et double lecture (avec une troisième lecture en cas de discordance entre les radiologues hospitaliers). Les femmes classées positives après l'examen de dépistage seront transférées à leur médecin traitant pour le diagnostic et, le cas échéant, le traitement. Le contexte médical et sanitaire de ce programme est discuté, en particulier les raisons spécifiques qui ont poussé les promoteurs à développer un programme organisé de dépistage par mammographie.
Paper presented at a symposium on The Public Health Perspective of Social and Preventive Medicine, in celebration of the 20th anniversary of the Department of Social and Preventive Medicine, University of Berne, 25 June 1992 in Berne. 相似文献
117.
Rainer Amann Carlo Alberto Maggi Sandro Giuliani Josef Donnerer Fred Lembeck 《Naunyn-Schmiedeberg's archives of pharmacology》1990,341(6):534-537
Summary In the superfused isolated rat urinary bladder, capsaicin as well as electrical field stimulation evoked the release of calcitonin gene-related peptide-like immunoreactivity (CGRP-IR). Carbonyl cyanide p-trichloromethoxyphenylhydrazone (CCCP, threshold 2 M) reduced both, the capsaicin- and the electrical field stimulation-evoked release of CGRP-IR while a low concentration of Ruthenium Red (RR, 0.6 M and 2 M) selectively attenuated the capsaicin-evoked release of CGRP-IR but did not influence the effect of electrical field stimulation. 20 M RR nearly abolished the capsaicin-evoked release, but also attenuated the effect of electrical field stimulation.In the isolated guinea-pig bronchus, electrical field stimulation and capsaicin induced non-cholinergic contractions which are known to be caused by tachykinin release from afferent nerve terminals. CCCP (0.6 M) only reduced the response to field stimulation; a ten-fold higher concentration of CCCP attenuated field stimulation as well as capsaicin-induced contractions. This is in contrast to the reported selective inhibition of capsaic-ininduced contractions by RR.The present data demonstrate that CCCP generally inhibits evoked neuropeptide release, regardless of the kind of stimulation used while low concentrations of RR preferentially inhibit capsaicin-evoked neuropeptide release.Send offprint requests to: R. Amann at the above address 相似文献
118.
Preventive effect of magnesium supplement on noise-induced hearing loss in the guinea pig 总被引:1,自引:0,他引:1
The effect of magnesium (Mg) on noise-induced hearing loss was investigated in two groups of adult pigmented guinea pigs
maintained either on optimal or suboptimal (physiologically high or low) Mg produced by different diets. The total Mg concentrations
of the perilymph (PL), cerebrospinal fluid, blood plasma and red blood cells were measured by atomic absorption spectrometry
and were found to differ significantly between the two groups (P < 0.01). One ear of each animal was exposed to either a single shooting impulse at a peak pressure level of 187 dB or two
impulse noise series at a rate of 1/s and peak pressure levels of 150 dB (1,000 impulses) and 167 dB (2,280 impulses), respectively.
Temporary (TTS) and permanent (PTS) hearing threshold shifts in anesthetized animals were measured 2 h and 1 week after the
noise exposure, using auditory brain stem response (ABR) audiometry at a frequency range from 3.75 to 30 kHz. Exposure to
the single noise impulse resulted in a mean TTS that was significantly lower in the high Mg group than that in the low Mg
group (P < 0.05), although no substantial PTS was observed in either group. In the animals exposed to 150 dB noise, the TTS showed
a tendency towards an Mg-related reduction at the higher frequencies. A small difference in PTS was found between the low
Mg and high Mg groups, but was not significant. Exposure to the 167-dB noise series caused a considerable TTS, which was significantly
lower in the high Mg group at 7.5 and 15 kHz than in the low Mg group (P < 0.05). The mean PTS showed a significant difference between the two Mg groups over the whole frequency range (P < 0.05) and was found to correlate negatively with the total Mg concentrations of both PL and plasma (P < 0.05). Moreover, the high Mg group showed a faster recovery from the hearing threshold shift than the low Mg group. The
present findings show that preventive oral Mg supplements can significantly reduce the rate of acoustic trauma caused by high-level
impulse noise exposure in the guinea pig.
Received: 23 March 1999 / Accepted: 15 April 1999 相似文献
119.
Marttin Emmeline Verhoef J. Coos Cullander Christopher Romeijn Stefan G. Nagelkerke J. Fred Merkus Frans W. H. M. 《Pharmaceutical research》1997,14(5):631-637
Purpose. To visualize the transport pathway(s) of high molecular weight model compounds across rat nasal epithelium in vivousing confocal laser scanning microscopy. Furthermore, the influence of nasal absorption enhancers (randomly methylated -cyclodextrin and sodium taurodihydrofusidate) on this transport was studied.
Methods. Fluorescein isothiocyanate (FITC)-labelled dextrans with a molecular weight of 3,000 or 10,000 Da were administered intranasally to rats. Fifteen minutes after administration the tissue was fixed with Bouin. The nasal septum was surgically removed and stained with Evans Blue protein stain or DiIC18(5) lipid stain prior to visualization with the confocal laser scanning microscope.
Results. Transport of FITC-dextran 3,000 across nasal epithelium occurred via the paracellular pathway. Endocytosis of FITC-dextran 3,000 was also shown. In the presence of randomly methylated -cyclodextrin 2% (w/v) similar transport pathways for FITC-dextran 3,000 were observed. With sodium taurodihydrofusidate 1% (w/v) the transport route was also paracellular with endocytosis, but cells were swollen and mucus was extruded into the nasal cavity. For FITC-dextran 10,000 hardly any transport was observed without enhancer, or after co-administration with randomly methylated -cyclodextrin 2% (w/v). Co-administration with sodium taurodihydrofusidate 1% (w/v) resulted in paracellular transport of FITC-dextran 10,000, but morphological changes, i.e. swelling of cells and mucus extrusion, were observed.
Conclusions. Confocal laser scanning microscopy is a suitable approach to visualize the transport pathways of high molecular weight hydrophilic compounds across nasal epithelium, and to study the effects of absorption enhancers on drug transport and cell morphology. 相似文献
120.
Boddy Alexander W. Snikeris Fred C. Kringle Robert O. Wei Greg C. G. Oppermann James A. Midha K. K. 《Pharmaceutical research》1995,12(12):1865-1868
Purpose. Highly variable drugs pose a problem in bioequivalence assessment because they often fail to meet current regulatory acceptance criteria for average bioequivalence (80–125%). This paper examines alternative approaches to establishing bioequivalence.
Methods. Suggested solutions have included alternate study designs, e.g., replicate and multiple dose studies, reducing the level of the confidence interval, and widening the acceptance limits. We focus on the latter approach.
Results. A rationale is presented for defining wider acceptance limits for highly variable drugs. Two previously described methods are evaluated, and a new method having more desirable properties is proposed.
Conclusions. We challenge the one size fits all current definition of bioequivalence acceptance limits for highly variable drugs, proposing alternative limits or goal posts which vary in accordance with the intrasubject variability of the reference product. 相似文献