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LEARNING OBJECTIVES: After studying this article, the reader should be able to: 1. Describe the soft-tissue, cartilaginous, and bony anatomy of the nose. 2. Describe the anatomy and function of the nasal valves. 3. Discuss the governing physiologic principles responsible for airflow dynamics. 4. Discuss the various functions of the nose. 5. Demonstrate an appropriate evaluation of the nasal airway. 6. Discuss the differential diagnosis of nasal obstruction. 7. Discuss appropriate management options for nasal airway obstruction.The nose is a complex, multifunctional organ that requires respect and understanding from the rhinoplasty surgeon. The etiologic and pathologic characteristics of each patient's nasal airway problem determine the treatment of the nasal airway. Frequently, medical management is sufficient without operative intervention. Recent advances have shown that nasal valves in airway patency may play a more important role than the septum. The rhinoplasty surgeon's understanding of the anatomy and physiology of the nasal airway, along with the causes of obstruction, can pave the way for a proper evaluation and appropriate management of nasal airway problems. Lack of understanding can result in misdiagnosis and mismanagement. This article outlines current concepts of medical and surgical management of nasal airway problems and discusses in detail the key concepts and principles in the practical management of the nasal airway. 相似文献
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Life-history characteristics of the double-ended pipefish, Syngnathoides biaculeatus (Bloch), were investigated to determine growth rate, degree of sexual dimorphism, size at maturity, and reproductive biology. Growth rates of wild juveniles and adults calculated from monthly progression of length-frequency modes ranged from 0.8mmd–1 (fish lengths 120–145mm standard length (SL)) in summer to 0.2mmd–1 in winter (185–200mm SL). Growth of laboratory-reared juveniles up to 63d old was greater, ranging from 0.8 to 2.3mmd-1. The von Bertalanffy growth constant K was estimated at 0.0076d- 1, or 2.8year–1. Morphological differentiation between the sexes based upon abdominal pattern was possible for fish larger than 120mm SL, with females possessing a zigzag pattern on the abdomen. The association between this pattern and sex was confirmed by histological gonad analysis. Males were significantly longer than females during four of seven seasons examined, and a 1:1 sex ratio was determined for all seasons except autumn when the ratio was female biased. The breeding season was marked by the appearance of pregnant males between October and April, and during courtship both species exhibited increased pigmentation. The minimum paternal size at maturity was 185mm, the maximum length recorded 260mm. Clutch size ranged between 60 and 200 eggs, with a mean of 153. Ovaries had a sequential pattern of egg development, resulting in egg batches that approximated the number of eggs carried by brooding males. Additionally, all eggs in a brood were at the same developmental stage. This suggests that one female provides all of the eggs for one male per breeding event in a monogamous mating system. 相似文献
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The induction of flowering by one long day (LD) in the grass Lolium temulentum is most closely mimicked by application of the gibberellins (GAs) GA(5) or GA(6), both of which occur naturally. These gibberellins promote floral development but have little effect on stem elongation. Endogenous GA(5) and GA(6) contents in the shoot apex double on the day after the LD and, for GA(5) (and we presume for GA(6) as well) reach a concentration known to be inductive for the excised shoot apex in vitro. They are, therefore, strong candidates as LD floral stimuli in this grass. The synthesis of GA(6) and an examination of its florigenic properties in L. temulentum are described. 相似文献
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