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71.
Haemangiomas are the most common tumours of infancy. They typically proliferate then involute with considerable variation as regards to their rates of proliferation and involution. Haemangioma of the nasal tip is a lesion of special characteristics. During proliferation, it expands, contracts and deviates the nasal cartilages. Particularly, it regresses slowly and frequently involutes incompletely. That is why excision of the lesion is frequently suggested. The present study was conducted to evaluate open rhinoplasty after initial non-excision treatment modalities namely, intra-lesional corticosteroid injections and laser treatment, as a protocol of treatment for nasal tip haemangiomas. Twelve patients with nasal tip haemangiomas were included in the present study. Patients of both sexes, of different ages, with deep and mixed haemangiomas were studied. Disfigurement was the constant presenting symptom. Initial non-excision treatment reported different responses as denoted by the regression of the lesions’ size. Haemangiomas constantly extended between the medial crura of the alar cartilages as noted by the constant widening of the columella pre-operatively and the obvious separation of the nasal cartilages intra-operatively. This separation was constantly found to require approximation by sutures. The results of the present study concluded that whenever an early presentation with nasal tip haemangioma could be established, initial non-excision treatment followed by open rhinoplasty could be a useful protocol of treatment. Within the limitations of the present study, this protocol could achieve an early, safe and effective treatment for nasal tip haemangiomas with provisionally acceptable cosmetic outcomes so far.  相似文献   
72.
This study investigates whether tissue recoil or patient intrinsic factors influence the final position of the nipple areola complex (NAC) after reduction mammoplasty. The age, pre-operative ptosis, BMI and weight of the tissue resected were recorded as patient intrinsic factors in 37 patients undergoing reduction mammoplasty. The “spring-back” value was defined as the distance from the sternal notch to a nipple landmark on the breast meridian with the patient sitting up, minus the same measurement repeated with the patient recumbent to eliminate the pull of gravity on the breast. Spring back was measured pre-operatively for the nipple and nipple mark then post-operative for the nipple. The difference in centimeters between the final post-operative distance from the sternal notch to the nipple and the level intended by the pre-operative nipple mark was termed the “judgment error.” The final position of the post-operative nipple and the judgment error was compared to the spring-back values and patient intrinsic factors. Pre-operative ptosis was statistically related to increasing patient BMI and mass of tissue resected per breast. Pre-operative spring-back values for the nipple increased with increasing ptosis, BMI and decreasing age. Spring-back values were greater in the lower pole of the breast than in the upper pole. The final position of the nipple was higher than the pre-operative mark in 65% of cases, lower in 8% and as marked in 27% of cases. The post-operative NAC was, on average, 0.6 cm higher than planned pre-operatively. The post-operative distance from the sternal notch to the nipple increased with increasing pre-operative ptosis, mass of breast tissue resected per breast and all three spring-back values. The difference between the level of the pre-operative mark and the final nipple position showed a weak correlation with post-operative spring-back values. The parameters of ptosis, BMI, weight of tissue resected per breast and pre-operative nipple spring back reflect body habitus and breast size. Spring-back values vary between the upper and lower pole of the breast. The final NAC position was higher than that intended at pre-operative marking in the majority of cases. The surgeon instinctively marks the nipple lower in patients with greater pre-operative ptosis and in whom a larger resection is anticipated. Judgment error did not relate to intrinsic factors nor to pre-operative spring-back values; hence, these parameters cannot be applied as predictive tools for more accurate pre-operative marking of the nipple position. This study suggests that the pre-operative nipple mark should be placed, with the patient sitting up, at least 23 cm from the sternal notch and 0.6 cm lower than the final position estimated using the inframammary crease as a landmark. An invited commentary on this paper is available at .  相似文献   
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74.
Conclusions  Noninvasive imaging of neurohumoral upregulation in remodeled myocardium suggests that an imaging strategy can be developed for predicting the rate of remodeling and likelihood of HF development. This should allow a more judicious use of neurohumoral antagonists especially in subjects who do not have manifest HF.74 In others specific targeted imaging may allow timely selection of individualized treatment strategies and ensure optimization of therapeutic intervention. Similar to ACE and AII receptors, multiple other targets in the hormonal cascades can identify the likelihood of adverse and favorable remodeling.74  相似文献   
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The neurotransmitter biosynthetic enzymes, tyrosine hydroxylase (TH), and tryptophan hydroxylase (TPH) are each composed of an amino-terminal regulatory domain and a carboxylterminal catalytic domain. A chimeric hydroxylase was generated by coupling the regulatory domain of TH (TH-R) to the catalytic domain of TPH (TPH-C) and expressing the recombinant enzyme in bacteria. The chimeric junction was created at proline 165 in TH and proline 106 in TPH because this residue is within a conserved five amino-acid span (ValProTrpPhePro) that defines the beginning of the highly homologous catalytic domains of TH and TPH. Radioenzymatic activity assays demonstrated that the TH-R/TPH-C chimera hydroxylates tryptophan, but not tyrosine. Therefore, the regulatory domain does not confer substrate specificity. Although the TH-R/TPH-C enzyme did serve as a substrate for protein kinase (PKA), activation was not observed following phosphorylation. Phosphorylation studies in combination with kinetic data provided evidence that TH-R does not exert a dominant influence on TPH-C. Stability assays revealed that, whereas TH exhibited a t1/2 of 84 min at 37°C, TPH was much less stable (t 1/2=28.3 min). The stability profile of TH-R/TPH-C, however, was superimposable on that of TH. Removal of the regulatory domain (a deletion of 165 amino acids from the N-terminus) of TH rendered the catalytic domain highly unstable, as demonstrated by at 1/2 of 14 min. The authors conclude that the regulatory domain of TH functions as a stabilizer of enzyme activity. As a corollary, the well-characterized instability of TPH may be attributed to the inability of its regulatory domain to stabilize the catalytic domain.  相似文献   
78.
A New York court recently struck down state Office of Mental Health regulations governing research involving subjects with impaired decisionmaking capacity. The court held that neither incapacitated adults nor minors could participate in any research protocol that contained a nontherapeutic element, irrespective of possible benefits to the subject or the importance of the knowledge to be gained. Although the decision rested on a technical point of law and dealt only with psychiatric research, the court's holding has significantly broader implications.  相似文献   
79.
The clinical research coordinator plays a crucial role in organizing a site's participation in the expanding arena of multicenter medical and pharmacologic clinical trials. This summary clarifies the role of the clinical research coordinator for inexperienced staff members assuming these responsibilities and outlines planning procedures leading to successful implementation. Emphasis is placed on establishing an interdependent relationship with the principal investigator, careful protocol assessment, team building, and staff feedback. Useful tools such as study manuals and physicians' study orders are described.  相似文献   
80.
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