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81.
We report two patients with paraneoplastic limbic and brainstem encephalitis associated with occult nonmetastatic testicular seminoma. In each patient, the neoplasm was detectable only by testicular ultrasonography. Male patients with this syndrome in whom lung cancer is not found should undergo testicular ultrasonography as part of the search for an extrapulmonary neoplasm. A normal clinical testicular examination is insufficient to exclude an occult seminoma. 相似文献
82.
Isolation of porcine circovirus-like viruses from pigs with a wasting disease in the USA and Europe 总被引:3,自引:0,他引:3
GM Allan F McNeilly S Kennedy B Daft EG Clarke JA Ellis DM Haines BM Meehan BM Adair 《Canadian Metallurgical Quarterly》1998,10(1):3-10
Sinus pericranii is an anomalous extracranial vascular malformation that is in continuity with the intracranial dural venous sinuses. Five case reports, three congenital and two traumatic, are described. Clinical management, including evaluation, diagnosis, and treatment, is discussed. Awareness of this entity by plastic surgeons will allow for earlier diagnosis and appropriate surgical management, resulting in decreased risk of complications. 相似文献
83.
The effect of external calcium concentration ([Ca2+]o) on membrane potential-dependent calcium signals in isolated tiger salamander rod and cone photoreceptor inner segments was investigated with patch-clamp and calcium imaging techniques. Mild depolarizations led to increases in intracellular Ca2+ levels ([Ca2+]i) that were smaller when [Ca2+]o was elevated to 10 mM than when it was 3 mM, even though maximum Ca2+ conductance increased 30% with the increase in [Ca2+]o. When external calcium was lowered to 1 mM [Ca2+]o, maximum Ca2+ conductance was reduced, as expected, but the mild depolarization-induced increase in [Ca2+]i was larger than in 3 mM [Ca2+]o. In contrast, when photoreceptors were strongly depolarized, the increase in [Ca2+]i was less when [Ca2+]o was reduced. An explanation for these observations comes from an assessment of Ca2+ channel gating in voltage-clamped photoreceptors under changing conditions of [Ca2+]o. Although Ca2+ conductance increased with increasing [Ca2+]o, surface charge effects dictated large shifts in the voltage dependence of Ca2+ channel gating. Relative to the control condition (3 mM [Ca2+]o), 10 mM [Ca2+]o shifted Ca2+ channel activation 8 mV positive, reducing channel open probability over a broad range of potentials. Reducing [Ca2+]o to 1 mM reduced Ca2+ conductance but shifted Ca2+ channel activation negative by 6 mV. Thus the intracellular calcium signals reflect a balance between competing changes in gating and permeation of Ca2+ channels mediated by [Ca2+]o. In mildly depolarized cells, the [Ca2+]o-induced changes in Ca2+ channel activation proved stronger than the [Ca2+]o-induced changes in conductance. In response to the larger depolarizations caused by 80 mM [K+]o, the opposite is true, with conductance changes dominating the effects on channel activation. 相似文献
84.
Nature-nurture in the classroom: entrance age, school readiness, and learning in children 总被引:1,自引:0,他引:1
The impact of entrance age on reading and mathematics achievement in 1st grade was examined. Methodological problems with past research were identified, including small size of achievement differences, failure to take background variables into account, and confusion of achievement levels with degree of learning. Using a pre-post design, growth of reading and mathematics was examined in younger 1st graders, older 1st graders, and older kindergarteners. Comparisons of background information on these groups with children who were either held out prior to or retained an extra year in kindergarten, produced minimal background differences. Results revealed that younger 1st graders made as much progress over the school year as did older 1st graders and made far more progress than older kindergarteners. Overall, findings demonstrated that, in itself, entrance age was not a good predictor of learning or academic risk. 相似文献
85.
A Mitchener DJ Wyper J Patterson DM Hadley JT Wilson LC Scott M Jones GM Teasdale 《Canadian Metallurgical Quarterly》1997,62(6):633-636
We report a case of cervicofacial necrotizing fasciitis that developed after blepharoplasty, an occurrence that, to our knowledge, has not previously been reported in the medical literature. A patient who presented to our institution 3 days after undergoing blepharoplasty of the upper eyelid was diagnosed as having fulminant fasciitis involving extensive areas of the face, scalp, and neck. We review the case in detail and discuss clinical and radiological clues to diagnosis, surgical and medical management, wound care, and subsequent scar contracture. This case emphasizes the need for individualized, appropriate postoperative care and for an awareness of this rare, potentially fatal complication. Early recognition and aggressive treatment of cervicofacial fasciitis can arrest its rapid progression and prevent devastating sequelae. 相似文献
86.
DM Kulibaba VN Novozhilov EG Tsvetkov VG Medvedev 《Canadian Metallurgical Quarterly》1997,156(2):117-118
Access and visualization in the implant-abutment area are often compromised. Tissue impingement and lack of abutment position verification may result in inaccurate fit. 相似文献
87.
DM Clark PM Salkovskis LG Ost E Breitholtz KA Koehler BE Westling A Jeavons M Gelder 《Canadian Metallurgical Quarterly》1997,65(2):203-213
Cognitive accounts of panic predict that panic disorder patients will be particularly prone to misinterpret autonomic sensations. Several studies have produced results consistent with this prediction, but each is open to alternative interpretation. To clarify matters, 2 studies administered the Body Sensations Interpretation Questionnaire (BSIQ) to panic patients and controls. Panic patients were more likely to interpret ambiguous autonomic sensations as signs of immediately impending physical or mental disaster and were more likely than other anxiety disorder patients and nonpatients to believe these interpretations. In a 3rd study, a brief version of the BSIQ was shown to have satisfactory test-retest reliability, to change with treatment, and to discriminate treatments that varied in their effects on panic. 相似文献
88.
MD Medlock JR Madsen PD Barnes DS Anthony LE Cohen RM Scott 《Canadian Metallurgical Quarterly》1997,27(3):121-128
There are many in vivo animal models for studying airway mucus secretion and hypersecretion, each with advantages and disadvantages. Use of a particular test system will depend upon the aspect of secretion to be modelled. Airway hypersecretory diseases exhibit chronic mucus hypersecretion, of which the clinical impact is predominantly in the distal airways. The majority of documented test preparations study acute secretion, invariably using tracheal preparations, but have been invaluable in elucidating the normal physiology of airway mucus secretion. Chronic models of the hypersecretory state in the distal airways have been developed, but are predominantly histologic in nature (for example quantification of increased goblet cell number). There are few investigations of mucus hypersecretion. Examination of the 'antisecretory' potential of pharmaceutical compounds has been investigated predominantly in chronic histologic models with the drug being given 'prophylactically' rather than 'therapeutically'. Refinement of chronic hypersecretory models should lead to elucidation of the connection between airway irritation, inflammation, MUC gene expression, mucous cell hyperplasia/metaplasia, airway hypersecretion and bronchial hypersecretory disease. 相似文献
89.
90.