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61.
OBJECTIVE: Auditory testing is not routinely performed within 4-6 weeks after stapedotomy, because hearing acuity is thought to be transiently depressed. In rare circumstances, postsurgical auditory and vestibular complaints may lead one to test hearing soon after stapedotomy. The early postoperative effects of carbon dioxide (CO2) and potassium titanyl phosphate (KTP) lasers, which now are routinely used to perform stapedotomies, have not been reported. The purpose of this report is to present normative data for auditory thresholds measured within 2 weeks of laser stapedotomy. STUDY DESIGN: The study design was a prospective, unblinded study. SETTING: The study was conducted at three academic medical centers. PATIENTS: Thirty-six subjects undergoing 38 stapedotomies for otosclerosis by 5 surgeons participated. MAIN OUTCOME MEASURES: Behavioral audiometry was performed using standard techniques beginning before surgery and continuing through > 1 year after surgery. RESULTS: The CO2 laser was used in 26 stapedotomies and the KTP laser was used in 12. Nine cases were revision procedures. Bone conduction pure-tone averages and speech discrimination scores did not worsen during the early postoperative period. Bone conduction at 250 and 4,000 Hz dropped slightly within the first 2 weeks (-4.3 and -6.7 dB) but recovered thereafter. Bone conduction at 1,000 Hz actually improved within the first week after surgery (+6.2 dB, p = 0.021). Significant improvements in air conduction thresholds (and air-bone gap) were seen at the second week and late audiometry. The results for CO2 and KTP laser-treated groups were not significantly different. CONCLUSIONS: Cochlear function is not significantly depressed in the early postoperative period after laser (CO2 or KTP) stapedotomy.  相似文献   
62.
The removal of tooth structure during preparation results in varying degrees of pulpal hyperemia. The ability of the pulpal tissue to respond either by recovery or degeneration depends in part upon the adequacy and fit of the provisional restoration. The response of the gingival tissue also depends on a large degree on the success of the temporary coverage. Provisional restorations are commonly given less attention and importance thereby biologic, mechanical, and esthetic considerations are not adequately met. Since a provisional restoration must be made or improvised during the same appointment in which the abutment teeth are prepared, costly chairside time most often leads to an unacceptable restoration. Failures such as color instability, color incompatibility, inappropriate anatomic contours, fractures, occlusal disharmony, changes in tooth position, gingival inflammation, and unhealthy periodontal conditions are usually encountered. A technique of fabricating an exacting provisional restoration with compliance to optimum quality is presented.  相似文献   
63.
Ninety-two-kilodalton type IV collagenase (MMP-9) is present in aortic aneurysms and may be important to the pathogenesis of this disease. Alteration in expression of MMP-9 or its inhibitor, the tissue inhibitor of metalloproteinase type 1 (TIMP-1), could increase degradation of extracellular matrix and lead to aneurysm formation. The purpose of this study was (1) to measure tissue levels of MMP-9 and TIMP-1 mRNA in aneurysmal (AAA), atherosclerotic occlusive (AOD), and normal (NL) human infrarenal aorta; (2) to test for their expression by cultured AAA and NL vascular smooth muscle cells (VSMCs); and (3) to locate in situ the cells responsible for mRNA production within AAA, AOD, and NL aortic wall. Total RNA extracted from AAA (n = 8), AOD (n = 8), and NL (n = 7) tissue was subjected to Northern analysis. Signals for MMP-9 and TIMP-1 were normalized to alpha-tubulin. Mean values +/- SEM were compared by ANOVA. NL and AAA VSMCs were cultured, passaged, and grown to confluence before RNA extraction and Northern analysis. In situ hybridization with digoxigenin-labeled RNA probes localized cells responsible for MMP-9 and TIMP-1 mRNA expression within sections of AAA (n = 5), AOD (n = 2), and NL (n = 2) aorta. MMP-9 mRNA levels were significantly greater in AAA (0.855 +/- 0.180) than NL (0.046 +/- 0.23) (P < .02), but differences between AOD (0.406 +/- 0.196) and AAA or AOD and NL were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
64.
New trends in surgical treatment of purulent tendovaginitis of the hand are described on the basis of clinical data of 295 patients with purulent tendovaginitis and its complications. A sparing operation technique was used as well as the fractional bathing of the purulent focus and regional antibacterial therapy at the postoperative period. This method of surgical treatment resulted in a shorter first stage of inflammation, less risk of complications (dermatogenic contracture, limited mobility in the joints of the fingers and toes, trophoneurotic disturbances) and less influence of injurious factors on the tendon in the process of treatment.  相似文献   
65.
The experience and the technique of cholecystectomy from mini-approach with elements of open laparascopic technique (MSE) in 102 patients with choledocholithiasis and calculous cholecystitis is descubed. In 99 cases the operation was carried out for chronic calculous cholecystitis, in 3 cases--for acute calculous cholecystitis. The patients were aged from 23 to 76 years (mean age 59.3 +/- 3.4 years). The average length of the incision in performing MSE made up 4.1 +/- 0.3 cm. Mean duration of the operation 42.4 +/- 5.3 min. In 5 cases (4.9%) intraoperative cholangiography was performed. The possibility to avoid the use of narcotic analgetics in postoperative period in patients who underwent MSE is demonstrated. Postoperative period made up 3.8 days. Social and cost-effect aspects of different modes of surgical treatment of patients with cholelithiasis are considered. The study of quality of life index makes it possible to come to conclusion about quicker return of the patients who underwent MSE to their habitual social and intellectual activities, practically complete absence of the influence of negative factors of conventional treatment (pains, dyspepsial, cosmetic defects) higher appreciation of their health conditions, well being, which manifests in higher quality of life in operated patients.  相似文献   
66.
The 37-kDa recombinant protein Asp f 2, encoding an allergen of Aspergillus fumigatus, was expressed in a prokaryotic expression system and immunologically evaluated for its functional and structural properties. The open reading frame for a 310-amino-acid-long protein was shown to encode a signal peptide of 31 amino acids. A native 37-kDa culture filtrate protein and a 55-kDa mycelial glycoprotein (gp55) exhibited complete N-terminal sequence homology to Asp f 2. A GenBank search for homologous proteins revealed 60 and 44% sequence homologies to the cytosolic protein ASPND1 from Aspergillus nidulans and fibrinogen binding protein from Candida albicans, respectively. The glycosylation sites and cysteine molecules are conserved in all the three proteins. The extracellular matrix protein laminin showed a dose-dependent interaction with Asp f 2. This protein, expressed as a major cell-associated protein within 24 h of in vitro fungal culture, comprises 20 to 40% of total fungal protein. Furthermore, both native and recombinant Asp f 2 exhibited specific immunoglobulin (IgE) binding with allergic bronchopulmonary aspergillosis (ABPA) and cystic fibrosis-ABPA patients, whereas A. fumigatus-sensitized allergic asthma and normal control subjects failed to show IgE binding with Asp f 2. These results indicate that Asp f 2 is a major allergen of A. fumigatus exhibiting IgE antibody binding with sera from patients with ABPA. The antigen should be explored further for its potential role in the differential diagnosis of A. fumigatus-associated allergic diseases.  相似文献   
67.
68.
Bone morphogenetic proteins (BMPs) and their receptors (BMPRs) are thought to play an important role in bone morphogenesis. The purpose of this study was to determine the locations of BMP-2/-4, osteogenic protein-1 (OP-1, also termed BMP-7), and BMP type II receptor (BMPR-II) during rat fracture healing by immunostaining, and thereby elucidate the possible roles of the BMPs and BMPR-II in intramembranous ossification and endochondral ossification. In the early stage of fracture repair, the expression of BMP-2/-4 and OP-1 was strongly induced in the thickened periosteum near the fracture ends, and coincided with an enhanced expression of BMPR-II. On day 7 after fracture, staining for BMP-2/-4 and OP-1 immunostaining was increased in various types of chondrocytes, and was strong in fibroblast-like spindle cells and proliferating chondrocytes in endochondral bone. On day 14 after fracture, staining with OP-1 antibody disappeared in proliferating and mature chondrocytes, while BMP-2/-4 staining continued in various types of chondrocytes until the late stage. In the newly formed trabecular bone, BMP-2/-4 and OP-1 were present at various levels. BMPR-II was actively expressed in both intramembranous ossification and endochondral ossification. Additionally, immunostaining for BMP-2/-4 and OP-1 was observed in multinucleated osteoclast-like cells on the newly formed trabecular bone, along with BMPR-II. In reference to our previous study of BMP type I receptors (BMPR-IA and BMPR-IB), BMPR-II was found to be co-localized with BMPR-IA and BMPR-IB. BMP-2/-4 and OP-1 antibodies exhibited distinct and overlapping immunostaining patterns during fracture repair. OP-1 may act predominantly in the initial phase of endochondral ossification, while BMP-2/-4 acts throughout this process. Thus, these findings suggested that BMPs acting through their BMP receptors may play major roles in modulating the sequential events leading to bone formation.  相似文献   
69.
Papain, thermitase and pepsin at pH 4.0 hydrolyze ovalbumin to low molecular weight peptides. Simultaneously a stepwise formation of several short fragments resulting in the appearance of a group of high molecular weight fragments and a subsequent splitting of the latter into two fragments of intermediate molecular mass takes place. The fragments are retained in the molecule by noncovalent bonds. The fragments formed under the action of different enzymes are similar in size, which is suggestive of splitting in the same narrow segments of the ovalbumin polypeptide chain. The results obtained indicate that during proteolysis of the native ovalbumin two extreme types of the proteolysis--the one-by-one and zipper types--occur in parallel, while the course of the latter is largely determined by the ovalbumin structure.  相似文献   
70.
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