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21.
Silvio Taschieri Massimo Del Fabbro Tiziano Testori Luca Francetti Roberto Weinstein 《Journal of oral and maxillofacial surgery》2006,64(2):235-242
PURPOSE: The introduction of microsurgical instruments and magnification devices has brought advantages in root-end management and the application of root-end filling materials. The main purpose of this prospective clinical study was to monitor the outcome of ultrasonic root-end preparation using magnification loupes or an endoscope. Tooth location and the presence of post restoration were also examined as potentially affecting the outcome. MATERIALS AND METHODS: Teeth treated surgically showed a periradicular lesion of strictly endodontic origin. A total of 59 patients were included in the study, according to specific selection criteria. Following the reflection of a full mucoperiosteal tissue flap, residual soft tissues were curetted, root ends were resected, and root-end cavities were prepared ultrasonically with a zirconium nitrate tip, and zinc oxide EBA-reinforced cement root-end fillings were placed. Thirty-two root-end management procedures were performed using magnification loupes and 39 using an endoscope. All cases followed for a period of 1 year were classified into 3 groups (success, uncertain healing, and failure) according to radiographic and clinical criteria. RESULTS: Of the 71 teeth evaluated at 1-year follow-up, 67 teeth (92.95%) successfully healed, 3 teeth had uncertain healing, and 2 failed. In the group using endoscopy, 94.9% of successful healing was achieved, while for the other group, 90.6% was recorded. We found no statistically significant differences in treatment results related to the arch (P = .20), post restoration (P = .21), or type of magnification device (P = .08). CONCLUSIONS: In the present study, adherence to a strict endodontic surgical protocol and the use of modern surgical endodontic procedures, together with visual magnifications, resulted in an overall high success rate. 相似文献
22.
Massimo Lemma Andrea Mangini Guido Gelpi Andrea Innorta Paolo Danna Francesco Lavarra Emanuela Piccaluga Carlo Antona 《European journal of cardio-thoracic surgery》2003,24(1):81-5; discussion 85
OBJECTIVE: It is not well established whether the blood flow of arterial composite Y-grafts can efficiently respond to the flow demand of the coronary system early postoperatively. The aim of this study was to evaluate if soon after the operation, arterial composite Y-grafts can increase blood flow in response to an increase in myocardial oxygen consumption (MVO2). METHODS: Twenty-seven patients who received complete arterial myocardial revascularization using the left internal thoracic artery (LITA) and the radial artery (RA) as composite Y-graft gave their consent to a pre-discharge coronary angiography and intravascular flow velocity measurements using a Doppler guide wire. Flow measurements were performed in the LITA main stem, the distal LITA and the RA, both at rest and during atrial pacing at the 85% of the patient age-predicted maximum. The heart rate-systolic blood pressure product was considered as an indirect index of MVO2. Hyperemic flow was determined after injection of adenosine. The flow reserve (FR) was defined as the ratio of blood flow during maximal hyperemia (Qmax) to baseline flow (Qbasal). RESULTS: Atrial pacing increased MVO2 significantly (P<0.000). None of the patients developed ischemic S-T segment modifications or complained of chest pain. Q(basal) increased significantly in the LITA main stem (P=0.001), distal LITA (P=0.041) and RA (P=0.004) while Qmax did not change significantly. As a consequence, the FR decreased in the LITA main stem (P=0.002), distal LITA (P<0.000) and RA (P<0.000) but was not completely exhausted. CONCLUSIONS: Soon after the operation, arterial composite Y-grafts can significantly increase blood flow in response to conditions of increased MVO2, keeping normal the myocardial O2 supply-to-demand ratio. 相似文献
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Walter Daghino MD Luigi Milano MD Sergio Ronco MD Giorgio Ronco MD Angelo Dettoni MD Massimo Cartesegna MD 《The Journal of foot and ankle surgery》2003,42(3):155-160
This article is a retrospective study comparing the efficacy of Regnauld arthroplasty to first ray osteotomies for the treatment of hallux valgus. One hundred consecutive cases of Regnauld arthroplasties were compared with 100 consecutive first ray osteotomies. One hundred fourty-one patients were available for follow-up, and based on clinical/radiographic examinations, 72 were treated with the osteotomy protocol (group A) and 69 with Regnauld arthroplasty (group B). Age at surgery, clinical symptoms, and preoperative radiologic findings were similar for the 2 groups; there was a preponderance of female patients (90%). The average follow-up was 49 months in group A and 51 months in group B. Clinical evaluation showed in the osteotomy group a more stable correction (79% v 49%), greater pain reduction (measured in a visual analog scale from 0 = pain free to 10 = deep intolerable pain), increased residual articular excursion of the first metatarsophalangeal joint (27 degrees of active dorsiflexion from neutral position v 8 degrees ), and less presence of central metatarsalgia (15% v 34%) (P <.05). The radiographic evaluation expressed more stable correction values in group A for the following parameters: joint preservation, sesamoid position, intermetatarsal angle (7 degrees v 12 degrees ), abduction angle of the hallux (14 degrees v 20 degrees ), and proximal articular set angle (8 degrees v 18 degrees ) (P <.05). 相似文献
26.
Liviana Da Dalt Silvia Callegaro Silvia Carraro Barbara Andreola Massimo Corradi Eugenio Baraldi 《Pediatric allergy and immunology》2007,18(2):100-104
Respiratory syncytial virus (RSV) bronchiolitis is a very common infection in infants and, after the acute phase, a number of patients develop a reactive airway disease that lasts for years. Although the pathogenesis of the lung damage after RSV bronchiolitis is still largely unknown, previous studies suggest that leukotrienes may play an active part in it. The aim of this study was to measure leukotriene levels in the nasal lavage fluid (NLF) collected in infants during RSV bronchiolitis and 1 month later. Cysteinyl leukotrienes (Cys-LTs) and leukotriene B(4) (LTB(4)) were measured in the NLF of 22 infants with their first episode of RSV bronchiolitis and 16 healthy infants. A second NLF sample was collected to measure leukotriene levels 1 month after the acute disease. NLF Cys-LT levels were significantly higher in infants with RSV bronchiolitis than in healthy controls [950 pg/ml (285.5-2155.9) vs. 110.5 pg/ml (66.5-451.3), p = 0.01], and they remained so a month after the acute infection (p = 0.02). A subanalysis showed no difference in Cys-LTs concentrations, either between bronchiolitis infants with and without a family history of atopy, or between those with and without passive exposure to cigarette smoke. No significant difference was found between the LTB(4) levels measured in the bronchiolitis cases and the control children. Cys-LTs are significantly increased in the NLF of infants with acute RSV bronchiolitis, and remain so at 1-month follow-up, suggesting a possible role of these eicosanoids in the pathogenesis of the disease. 相似文献
27.
Giuseppe Galardi Silvestro Micera Jacopo Carpaneto Silvana Scolari Massimo Gambini Paolo Dario 《Movement disorders》2003,18(11):1358-1367
We developed an automated and objective method to measure posture and voluntary movements in patients with cervical dystonia using Fastrack, an electromagnetic system consisting of a stationary transmitter station and four sensors. The junction lines between the sensors attached to the head produced geometrical figures on which the corresponding aspects of the head were superimposed. The head position in the space was reconstructed and observed from axial, sagittal, and coronal planes. Four patients with cervical dystonia and 6 healthy subjects were studied. Each patient was representative of one of the typical patterns of cervical dystonia. The study allowed the authors to collect quantitative data on posture and range of motion of the head. This pilot study demonstrates the efficacy of the Fastrack system to objectively measure the head position in cervical dystonia patients. 相似文献
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29.
R D Blumenthal R M Sharkey R Kashi A M Natale D M Goldenberg 《International journal of cancer. Journal international du cancer》1992,51(6):935-941
We evaluated the accretion of 131I-labeled NP-4 anticarcinoembryonic antigen (CEA) into 4 size-matched human colonic carcinomas grown s.c. in nude mice. Antibody uptake for LS174T and GW-39 tumors was relatively high (19 to 23% ID/g on day 3), whereas moderate uptake was seen in the Moser tumor (7.5% on day 3) and low uptake was detected in the GS-2 tumor (1.8% on day 3). Blood clearance of radioantibody was twice as fast in mice with GS-2 tumors than in mice with GW-39, LS174T or Moser tumors. Seven physiological parameters that might influence radioantibody accretion were evaluated in order to better understand the differences in observed tumor targeting: vascular volume, blood flow rate, vascular permeability, tumor antigen content, serum antigen content and complexation of radioantibody, intratumoral antigen distribution, and intracellular antigen distribution. Although marked variability in vascular physiology, antigen content and antibody complexation of the 4 tumors grown in the same host and site existed, it was insufficient to explain the differences in antibody uptake. However, intra-tumoral distribution of antigen, and sub-cellular accessibility of antigen for radioantibody were important considerations. GS-2 tumors are well differentiated and have polarized cells. CEA in GS-2 is largely inaccessible to radioantibody; most of the antigen is located in the lumen of the glands or on the apical surface of gland cells and most of the antibody distributes to the stromal region on the basolateral surface. The low antibody targeting in GS-2 could therefore be explained by restricted intra-tumor accessibility of antibody. Scatchard analysis of NP-4 binding to Moser cells under non-internalizing and internalizing conditions revealed that 90% of the antigen is found within the cell, unavailable to bind with the NP-4 antibody, which is slow to internalize. In contrast, CEA in LS174T cells was almost entirely accessible. The reduced antibody targeting to Moser xenografts might therefore, be explained by restricted antibody accessibility at the cellular level. 相似文献
30.
F Marchionni F Lannutti P Natale E Marchese G Bonetti D Troilo N Quadrini A Gadaleta F Volpe 《Minerva chirurgica》1992,47(21-22):1737-1740
The authors report a case of extrinsic stenosis of the sigmoid colon due to inflammation of the uterus and adjoining parts. Attention is drawn to the possibility that the radiological images of this condition may be similar to neoplastic diseases. 相似文献