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81.
82.
The value of Politzerization as a method of treatment in atelectatic ears and secretory otitis media is controversial. In some places it has been used routinely for decades, in others it has been almost forgotten. A quantitative study of its therapeutic value has been difficult to find. The present study is an attempt to evaluate the therapeutic value of such an 'air douche' in atelectatic ears. Thirteen middle ears with atelectasis were Politzerized daily with air or N2 for up to five consecutive days. Once Politzerized, the atelectasis and retraction pockets disappeared in all the ears examined. However, continuous observation of the Politzerized ears with the surgical microscope revealed that all the ear drums returned swiftly to their retracted position. The time it took for a drum to return to its original place varied from 15 minutes up to a maximum of 335 minutes. Our observations show that even an increased number of Politzerizations did not alter the speed of reappearance of the atelectasis. It would therefore seem that the therapeutic value of Politzerization in atelectatic ears is doubtful. 相似文献
83.
The ex vacuo theory, claiming that in cases of middle ear underaeration air enters the middle ear through the Eustachian tube in diminished amounts while oxygen continues to leave it into the blood by diffusion as in normal condition, does not provide a complete explanation for the aeration problems encountered in middle ear pathology. This study shows that when atelectatic ears are politzerized (hyperinflated) with different gases, these gases disappear with a speed that correspond to the diffusion coefficient of the different gases. This finding together with the fact that the composition of middle ear gases is very similar to that found in the venous circulation suggests that it is a diffusional process of several gases from the middle ear into the blood and in the opposite direction that mainly determines the middle ear pressure. 相似文献
84.
Purpose. To define sequence motifs that can be used to identify peptide ligands of the melanocortin receptor (MCR).
Methods. Screening of combinatorial libraries has led to identification of D-Trp-Nle-NH2 (Nle, norleucine) and D-Trp-Arg-NH2 as the smallest structures known to antagonize the amphibian MCR (1). As the basis of a search paradigm, peptide-ligands containing these or similar motifs within their larger primary structure were examined for ability to antagonize amphibian and recombinant human MCRs. Compounds examined include analogs of substance P, leutinizing-hormone releasing-hormone, endothelin, neurotensin, and opioid-somatostatin.
Results. Of seven compounds tested containing the predetermined search motif D-Trp-AAx (where AAx is Arg, Leu, Nle, or Ile), six were found to have previously unrecognized antagonist activity at the amphibian MCR (K
d 30 to 5000 nM). In contrast, of 14 similar control peptides lacking the D-Trp-AAx search motif, only somatostatin displayed measurable antagonist potency. The anticancer peptide, [Arg8, D-Trp7,9, N-methyl-Phe8]-substance P, was the most potent of the motif-containing peptides with a K
d of 31 nM. The µ-opioid antagonist D-Phecyclic[Cys-Tyr-D-Trp-Arg-Thr-Pen]-Thr-NH2 (CTAP) also blocked the amphibian MCR (K
d 1 µM), but the related µ-antagonist CTOP, different only by only by substitution of Arg with ornithine within the search motif, was found to agonize the amphibian MCR (EC50 67 nM). CTAP and the anticancer peptide were also tested on human MCRs (hMCRs); while CTAP competed with -MSH at the hMC1 receptor, the anticancer peptide had no effect or was slightly stimulatory.
Conclusions. We have identified dipeptide motifs that help distinguish antagonist ligands of the amphibian MCR from ligands known to interact with other G-protein coupled receptors. This approach might be generally applicable if motifs can identified for other receptors and their subtypes. In studies employing CTAP and CTOP, analogs previously considered highly selective for the µ-opioid receptor, cross-reaction with MCRs must be considered. 相似文献
85.
Treatment of cholesteatoma and retraction pockets 总被引:2,自引:0,他引:2
J. Sadé 《European archives of oto-rhino-laryngology》1993,250(4):193-199
Summary Treatment of retraction pockets (RP) and cholesteatomas depends on their nature and evolvement and the size of mastoid pneumatization. RP are secondary to vacillating middle ear negative pressure. Treatment when necessary consists of placing a ventilating tube, excision of the RP or both. In most children and adults, cholesteatoma is derived from RP (or atelectasis) of the tympanic membrane, where it can be termed retraction pocket cholesteatoma or secondary cholesteatoma. This type of cholesteatoma is associated with a non-pneumatized mastoid coupled by negative pressure. Approximately one-third of children's cholesteatomas present clinically behind an intact drum despite a pneumatized mastoid. Pathogenetically this type may be congenital or metaplastic and should be best termed primary cholesteatoma. Central perforations associated with cholesteatoma are probably derived from continuous tympanic membrane destruction by infection in cases of RP cholesteatomas or due to a primary cholesteatoma bursting out from the tympanic cavity. Canal-up surgery of cholesteatoma fails in 60% of cases at Tel Aviv University because of the inherent tendency of the tympanic membrane to retract once again. Residual disease was found in our cases to be a lesser cause for failure. Treatment depends on the type of cholesteatoma, emphasizing small radicals in sclerotic mastoids. When a pneumatized mastoid is encountered, a posterior tympanotomy should be considered.Presented at the Fourth International Conference on Cholesteatoma and Mastoid Surgery, Nigata, Japan; September 1992 相似文献
86.
87.
Sad?k Kadri A??kg?z Burak A?ar Selahattin Ayd?n Eser A??kg?z Okan Er Bar?? ?ensoy Mustafa Mücahit Balci ?a?r? Yayla Fatih ?en Salih Topal Sinan Aydo?du 《Medical principles and practice》2015,25(1):31-35
Objective
In the present study, the association between red cell distribution width (RDW) with functional significance of intermediate coronary artery lesions was investigated.Materials and Methods
Two hundred and forty-six consecutive patients, 168 males and 78 females, who underwent fractional flow reserve (FFR) measurement for angiographically intermediate coronary stenosis (40-70% in quantitative coronary analysis) in the left anterior descending coronary artery were enrolled into the study. The functional significance of intermediate coronary artery lesions was determined by FFR measurement. An FFR value <0.75 was defined as functionally significant. Venous blood samples were taken within 48 h before the FFR measurement, and RDW levels were determined by a Coulter LH Series hematology analyzer. Logistic regression analysis was used to examine the association between functional significance in FFR measurement and other variables.Results
Of the 246 patients, 62 (25.2%) exhibited significant functional stenosis (FFR <0.75) in the FFR measurement. The mean RDW level was significantly higher in patients with significant stenosis (14.19 ± 0.73 vs. 13.69 ± 0.77, p < 0.001). In stepwise multivariate logistic regression analysis, RDW (OR = 2.489, 95% CI = 1.631-3.799, p < 0.001) and male gender (OR = 2.826, 95% CI = 1.347-5.928, p = 0.006) were independent predictors of significant functional stenosis.Conclusion
Increased RDW levels were associated with functional significance of angiographically intermediate coronary artery stenoses.Key Words: Coronary artery stenosis, Fractional flow reserve, Erythrocyte indices, Red cell distribution width 相似文献88.
Isolated congenital nasal anomalies that cause remarkable aesthetic deformities are extremely rare, and only a few cases have been reported in the literature. In this study, we present the case of a patient with nonsyndromic congenital isolated absence of the nasal lower lateral cartilage and the subsequent esthetic surgical correction. A satisfactory result was achieved. Level of Evidence: Level V, therapeutic study. 相似文献
89.
Myocardial Fibrosis Is the Key Component of Hypertrophied Myocardium That Cause Fragmented QRS in Aortic Stenosis 下载免费PDF全文
90.
Ahmet Peker Okan ?i?ek ?i?dem Soydal Nuriye ?zlem Kü?ük Sad?k Bilgi? 《Diagnostic and interventional radiology (Ankara, Turkey)》2015,21(1):54-59