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91.
It is not known how well nasopharyngeal swab culture represents pneumococcal carriage status. We tested this by comparing swab culture to quantitative culture and quantitative PCR of mucosal tissue in a rat model of pneumococcal carriage. Quantitative culture and quantitative PCR identified significantly more carriers compared to swab culture (differences 15% and 33%, 95% CI 1-28% and 16-47%, p=0.04 and 0.001, respectively). The sensitivity and specificity of swab culture was 75/92% and 63/100% compared to quantitative tissue culture and quantitative PCR, respectively. The quantitative estimates of culture and PCR were very similar (Pearson correlation coefficient 0.79, p<0.001). In conclusion, even a well-controlled swab sampling markedly underestimates pneumococcal carriage rate, and simultaneous use of quantitative culture and PCR increases the number of positive samples by about one third.  相似文献   
92.
Glucocorticosteroids are the most effective drugs for controlling inflammation of allergic rhinitis (AR). Because of their strong pharmacological action, which can be a so-called 'double-edged sword', glucocorticosteroids are usually taken intranasally so as to reduce their potential for eliciting adverse effects. Accumulating evidence suggests that intranasal glucocorticosteroids control not only nasal symptoms but also ocular symptoms. In contrast to sedating H1-receptor antagonists, intranasal glucocorticosteroids can improve impaired performance such as daytime sleepiness associated with AR. In Japanese cedar pollinosis, treatment begun immediately after initiation of pollen release or onset of initial symptoms, known as prophylactic (initial) treatment, is recommended. The current version of the practical guideline for management of allergic rhinitis in Japan recommends the use of chemical mediator release inhibitors, second-generation H1-receptor antagonists, or leukotriene receptor antagonists for prophylactic treatment. However, recent evidence suggests that intranasal glucocorticosteroids might also be useful as first-line drugs for prophylactic treatment. The molecular mechanism of anti-inflammatory action of glucocorticosteroids supports this contention. Moreover, a meta-analysis of studies of intranasal glucocorticosteroids given as monotherapy has revealed that these agents are superior to oral H1-receptor antagonists and leukotriene antagonists for controlling major symptoms of AR. These findings suggest that glucocorticosteroids, especially intranasal glucocorticosteroids, might be positioned as first-line drugs for the treatment of both perennial and seasonal AR.  相似文献   
93.
目的:为鼻内镜下额隐窝区域手术提供相应的解剖基础。方法:(1)成人干颅骨5例(10侧),从正中矢状位锯开,观察额窦、额隐窝及毗邻骨性解剖结构;(2)成人湿性尸头5例(10侧),从正中矢状位锯开,观察额窦引流部位,以量角器、直尺等测量工具测量相关解剖数据;(3)另选成人湿性尸头标本5例(10侧),模拟经鼻内镜鼻丘径路额窦开放术,鼻内镜下观察额隐窝及毗邻结构解剖特征。结果:(1)额隐窝作为额窦引流通道,具有复杂的三维空间结构;(2)鼻内镜下经鼻丘径路额窦开放手术可充分暴露额隐窝范围,鼻丘、钩突和毗邻结构的解剖关系决定了具体的手术方式;(3)筛前动脉距鼻小柱与鼻翼交点(58.0±2.9)mm,与鼻底夹角(51.0±3.9)°,是辨认额窦口及前颅底的重要标志。结论:鼻丘、钩突及筛前动脉为鼻内镜下额隐窝区域手术的重要解剖标志,准确辨认额隐窝及毗邻结构的解剖关系,有助于提高手术的彻底性及避免严重的手术并发症。  相似文献   
94.
BACKGROUND: Involvement of paranasal sinuses has been suggested in allergic rhinitis but not clearly demonstrated. AIMS: To investigate the relationship between intermittent allergic rhinitis and computerized tomography (CT). METHODS: Twenty patients with intermittent rhinitis and sensitized to cypress pollens underwent unilateral nasal provocation tests (NPTs) using increasing concentrations of cypress pollens out of the pollen season. Sinus CT-scans were carried out just before a NPT and 24 h later. Nasal lavage was carried out just before a NPT, 30 min after a positive challenge and again 24 h later. Leucotriene C4/D4, intracellular adhesion molecule-1 and eosinophil cationic protein were measured in nasal secretions. RESULTS: Thirteen patients (65%) showed an alteration in their CT-scans after allergen challenge. Ten of them showed sinus changes controlateral to their allergenic provocation. Radiological changes mainly affected the osteomeatal complex and the ethmoid sinuses. Pre-existing abnormalities (13 of 20 cases) mainly concerned the maxillary sinuses. There was no correlation between CT-scan abnormalities and levels of mediators released in nasal secretions. CONCLUSIONS: We have shown that nasal allergen challenge can produce radiological changes in the paranasal sinuses. This mainly concerned the ethmoid sinuses.  相似文献   
95.
Aims : To evaluate the clinicopathological profile of 14 cases of nasal and paranasal sinusal adenocarcinoma, and to assess the usefulness of immunohistochemistry in the differential diagnosis of primary and metastatic intestinal-type adenocarcinoma.
Methods and results : Fourteen cases of nasal and paranasal adenocarcinoma, treated at IPOFG, Lisbon, between 1976 and 2002, were studied. Clinical records were reviewed and expression of cytokeratin (CK)7 and CK20 and of neuroendocrine markers was evaluated. The male : female ratio was 3 : 1, and the mean age of the patients was 65.3 years. Ten cases occurred in the paranasal sinuses. There was a history of professional exposure to dust in three patients. Twelve cases were high-grade intestinal type adenocarcinomas (ITAC) and two were low-grade. CK7 was present in 2/9 ITAC cases and CK20 in 8/9 ITAC and in cases of mixed and mucinous histology. All high-grade cases showed neuroendocrine differentiation. Seven of the 12 patients with high-grade adenocarcinoma died of the disease, with a mean follow-up of 47.4 months.
Conclusions : Nasal and paranasal adenocarcinoma mostly occurs in men in the 7th decade. ITAC is the most frequent histological type. The pattern of CK7/CK20 was not useful in the distinction between primary and metastatic intestinal adenocarcinoma. However, in the former, neuroendocrine differentiation proved to be a valuable tool in that distinction.  相似文献   
96.
In vitro diagnosis of chronic nasal inflammation   总被引:6,自引:0,他引:6  
BACKGROUND: Differential diagnosis of chronic nasal inflammation is insufficient when based solely on clinical examination and radiography of paranasal sinuses. Patients complain about more or less similar symptoms. Activation of mast cells and eosinophils is pivotal in nasal inflammation. OBJECTIVE: To compare tryptase and eosinophilic cationic protein (ECP) in nasal secretions in different forms of chronic nasal inflammation and to establish norm values. METHODS: The study included 1710 patients presenting with nasal complaints. Nasal secretions were gained by the cotton wool method and analysed for tryptase, as a marker of mast cell activation, and for ECP, as a marker of tissue eosinophilia and activation. Patients were grouped according to their diagnosis: chronic, non-allergic rhinosinusitis (sinusitis, n=194), non-allergic nasal polyposis (polyposis, n=138), non-allergic rhinitis with eosinophilia syndrome (NARES, n=198), isolated perennial allergic rhinitis (AR) (n=126), isolated seasonal AR (n=132), and patients allergic to both, seasonal and perennial allergens (n=193). Seven hundred and twenty-nine patients with nasal complaints due to a deviated septum and without any nasal inflammation served as controls. RESULTS: Nasal tryptase was highly significantly (P<0.001) elevated in polyposis, NARES, and in AR. ECP was highly significantly (P<0.001) elevated in all groups of patients suffering from chronic nasal inflammation. Based on our data and method we established norm values (95% confidence interval of mean value) for nasal tryptase in healthy adults, ranging from 12.0 to 18.7 ng/mL and for ECP ranging from 84.4 to 102.6 ng/mL. CONCLUSION: Mast cells and eosinophils are involved in non-allergic and allergic forms of chronic nasal inflammation. We established an in vitro assay for tryptase and ECP in nasal secretions and defined norm values based on our data and method. In vitro measurement of biological markers in nasal secretions provides important information for differential diagnosis and therapeutic strategies of chronic nasal inflammation.  相似文献   
97.
BACKGROUND: Clinical documentation about effects on local markers of inflammation of sublingual immunotherapy (SLIT) in children is still poor. METHODS: Twenty-four children (age range 4-16 years, average 8.5 years) monosensitized to house dust mites (HDMs) were randomized to receive active or placebo SLIT for this allergen according to a double-blind, placebo-controlled design. Before treatment and 10-12 months later the following parameters were checked: ECP and tryptase in sputum and nasal secretion, serum and nasal mite-specific IgE (sIgE), allergen-specific nasal challenge test (sNCT), nasal symptoms and tryptase after sNCT. RESULTS: Nasal tryptase and nasal IgE in basal conditions were unchanged in treated children but significantly increased in untreated children (P = 0.0156 and P = 0.0313, respectively). The threshold for sNCT was unchanged in both groups of children, but the symptom score after sNCT was unchanged in the placebo group and significantly decreased in the active group (P = 0.0084). The nasal tryptase after sNCT was unchanged in the active group and significantly increased in the placebo group (P = 0.0218). Intergroup comparison showed a significant difference in oral tryptase and nasal tryptase after sNCT in favour of the active group. CONCLUSIONS: These interim results after only 1 year of treatment show that SLIT in children monosensitized to HDMs is able to avoid the spontaneous increase in both nasal sIgE antibodies and in local allergic inflammation in basal conditions. These outcomes are confirmed and supported by the decrease of symptoms in the active group combined with the increase of nasal tryptase only in the control group in both cases after sNCT.  相似文献   
98.
BACKGROUND: Studies suggest that nasal treatment might influence lower airway symptoms and function in patients with comorbid rhinitis and asthma. We investigated the effect of intranasal, inhaled corticosteroid or the combination of both in patients with both pollen-induced rhinitis and asthma. METHODS: A total of 262 patients were randomized to 6 weeks' treatment with intranasal fluticasone propionate (INFP) 200 microg o.d., inhaled fluticasone propionate (IHFP) 250 microg b.i.d., their combination, or intranasal or inhaled placebo, in a multicentre, double-blind, parallel-group study. Treatment was started 2 weeks prior to the pollen season and patients recorded their nasal and bronchial symptoms twice daily. Before and after 4 and 6 weeks' treatment, the patients were assessed for lung function, methacholine responsiveness, and induced sputum cell counts. RESULTS: Intranasal fluticasone propionate significantly increased the percentages of patients reporting no nasal blockage, sneezing, or rhinorrhoea during the pollen season, compared with IHFP or intranasal or inhaled placebo. In contrast, only IHFP significantly improved morning peak-flow, forced expiratory volume in 1 second (FEV1) and methacholine PD20, and the seasonal increase in the sputum eosinophils and methacholine responsiveness. CONCLUSIONS: In patients with pollen-induced rhinitis and asthma, the combination of intranasal and IHFP is needed to control the seasonal increase in nasal and asthmatic symptoms.  相似文献   
99.
经鼻内窥镜选择性鼻中隔粘膜下切除术   总被引:4,自引:0,他引:4  
目的:探讨经鼻内窥镜选择性鼻中隔粘膜下切除术的意义及手术方法。方法:根据不同的手术目的对204例需要行鼻中隔手术的病人,经鼻内窥镜实施选择性鼻中隔粘膜下切除术。结果:采用该技术对单纯性鼻中隔偏曲患者手术临床治愈率100%,其手术有效治愈头痛、鼻阻及鼻出血等鼻中隔偏曲临床症状,达到临床治疗目的。未出现鼻腔粘连、鼻中隔穿孔等并发症。有2例形成鼻中隔血肿,经放置引流管处理后治愈。对于解除高位鼻中隔偏曲解剖异常引发的鼻窦炎,手术后效果良好。取鼻中隔软骨做为修补材料手术效果满意。结论:经鼻内镜选择性鼻中隔粘膜下切除术目的性强、方法灵活、创伤小、并发症少、手术效果确切。  相似文献   
100.
BACKGROUND: Studies have suggested that topical corticosteroids are effective in the treatment of nasal polyps; however, this has yet to be confirmed in a large, robust clinical trial. OBJECTIVE: To evaluate the efficacy and safety of mometasone furoate nasal spray (MFNS) for nasal polyposis. METHODS: A total of 354 subjects with bilateral nasal polyps and clinically significant congestion/obstruction participated in this multinational, randomized, double-blind, placebo-controlled study. Subjects received MFNS 200 microg once or twice daily or placebo for 4 months. Coprimary endpoints were (1) change from baseline to last assessment in physician-evaluated bilateral polyp grade score and (2) change from baseline averaged over month 1 in subject-assessed nasal congestion/obstruction. ANOVA was used for all efficacy endpoints, except for change in bilateral polyp grade score, for which baseline polyp grade was added as a covariate. RESULTS: Compared with placebo, MFNS 200 microg administered once or twice daily produced significantly greater reductions in bilateral polyp grade score (P < .001, P = .010, respectively) and congestion/obstruction (P = .001, P < .001), as well as improvement in loss of smell (P < .001, P = .036), anterior rhinorrhea (P < .001 for both), and postnasal drip (P < .001, P = .001) over month 1. MFNS 200 microg twice daily was superior to MFNS 200 microg once daily in reducing congestion/obstruction (P = .039), and there were more improvers in the MFNS 200 microg twice daily group (P = .035). MFNS was well tolerated in both groups. CONCLUSION: MFNS 200 mug, once or twice daily, was safe and significantly superior to placebo in reducing polyp grade (size and extent) and improving congestion/obstruction and return of sense of smell. MFNS is an effective medical treatment for nasal polyposis and may reduce or delay the need for surgery.  相似文献   
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