328 research outputs found

    BEVATRON OPERATION AND DEVELOPMENT. 64. October--December 1969.

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    Immediate implant placement and provisionalization:Aesthetic outcome 1 year after implant placement. A prospective clinical multicenter study

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    Contains fulltext : 220439.pdf (Publisher’s version ) (Closed access)BACKGROUND: Prospective aesthetic outcomes on a high number of patients after immediate implant placement and provisionalization (IIPP) are lacking. PURPOSE: To analyze the aesthetic outcome after IIPP. MATERIALS AND METHODS: One hundred consecutive patients with a failing maxillary incisor were provided with an immediately placed and provisionalized nonloaded implant using a flapless procedure and palatal implant positioning. The remaining gap buccally was filled with a bone substitute. Preoperatively (T0), 2 weeks postoperatively (T1), direct after placement of the permanent crown (T2), and 1 year after IIPP (T3), standardized light photographs were made. Change in aesthetic score was the primary outcome measure. Both the white aesthetic score (WES) and pink aesthetic score (PES) were used. RESULTS: In the first year postsurgery, the mean total-WES and total-PES scores raised from 4.5 to 8.2, and from 9.9 to 12.1, respectively. The mean PES scores for mesial and distal papilla, soft tissue marginal level, contour, color, and texture, raised significantly (P < .05), while the alveolar process contour, on average, remained stable from T0 to T3. CONCLUSIONS: Within the limitations of this 1-year research, it may be concluded that, following this minimal invasive IIPP procedure, a high aesthetic outcome was achieved

    In-Situ Nuclear Magnetic Resonance Investigation of Strain, Temperature, and Strain-Rate Variations of Deformation-Induced Vacancy Concentration in Aluminum

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    Critical strain to serrated flow in solid solution alloys exhibiting dynamic strain aging (DSA) or Portevin–LeChatelier effect is due to the strain-induced vacancy production. Nuclear magnetic resonance (NMR) techniques can be used to monitor in situ the dynamical behavior of point and line defects in materials during deformation, and these techniques are nondestructive and noninvasive. The new CUT-sequence pulse method allowed an accurate evaluation of the strain-enhanced vacancy diffusion and, thus, the excess vacancy concentration during deformation as a function of strain, strain rate, and temperature. Due to skin effect problems in metals at high frequencies, thin foils of Al were used and experimental results correlated with models based on vacancy production through mechanical work (vs thermal jogs), while in situ annealing of excess vacancies is noted at high temperatures. These correlations made it feasible to obtain explicit dependencies of the strain-induced vacancy concentration on test variables such as the strain, strain rate, and temperature. These studies clearly reveal the power and utility of these NMR techniques in the determination of deformation-induced vacancies in situ in a noninvasive fashion.

    Разработка импульсной системы питания сварочной дуги на базе искусственной формирующей линии

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    Объектом исследования является импульсная система питания сварочной дуги, горящей в динамическом режиме. Предмет исследования – система импульсного питания сварочной дуги на базе искусственной формирующей линии неплавящимся электродом. Цель работы – анализ и разработка импульсной системы питания сварочной дуги на базе искусственной формирующей линии неплавящимся электродом в аргоне. Создана действующая экспериментальная установка для сварки дугой горящей в динамическом режиме с униполярными импульсами. Достоверность результатов и выводов подтверждена их сходимостью с экспериментальными данными, полученными методом осциллографированияSubject of research – power system for welding in dynamic mode nonconsumable electrode unidirectional pulses of current. Purpose of research – research and development of the power system for non-consumable electrode arc welding in argon in dynamic mode. The acting experimental setup for non-consumable electrode arc welding in argon in dynamic mode was created. The validity of results and inferences was confirmed by their convergence with experimental data obtained by oscillographic testing of developed power system for non-consumable electrode arc welding in argon in dynamic mode

    Biochemical and developmental characterization of carbonic anhydrase II from chicken erythrocytes

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    <p>Abstract</p> <p>Background</p> <p>Carbonic anhydrase (CA) of the chicken has attracted attention for a long time because it has an important role in the eggshell formation. The developmental profile of CA-II isozyme levels in chicken erythrocytes has not been determined or reported. Furthermore, the relations with CA-II in erythrocyte and egg production are not discussed. In the present study, we isolated CA-II from erythrocytes of chickens and determined age-related changes of CA-II levels in erythrocytes.</p> <p>Methods</p> <p>Chicken CA-II was purified by a combination of column chromatography. The levels of CA-II in the hemolysate of the chicken were determined using the ELISA system in blood samples from 279 female chickens, ages 1 to 93 weeks, 69 male chickens, ages 3 to 59 weeks and 52 weeks female Araucana-chickens.</p> <p>Results</p> <p>The mean concentration of CA-II in hemolysate from 1-week-old female was 50.8 ± 11.9 mg/g of Hb. The mean levels of CA-II in 25-week-old (188.1 ± 82.6 mg/g of Hb), 31-week-old (193.6 ± 69.7 mg/g of Hb) and 49-week-old (203.8 ± 123.5 mg/g of Hb) female-chickens showed the highest level of CA-II. The levels of CA-II in female WL-chickens significantly decreased at 63 week (139.0 ± 19.3 mg/g of Hb). The levels of CA-II in female WL-chicken did not change from week 63 until week 93.The mean level of CA-II in hemolysate of 3-week-old male WL-chickens was 78.3 ± 20.7 mg/g of Hb. The levels of CA-II in male WL-chickens did not show changes in the week 3 to week 59 timeframe. The mean level of CA-II in 53-week-old female Araucana-chickens was 23.4 ± 1.78 mg/g of Hb. These levels of CA-II were about 11% of those of 49-week-old female WL-chickens. Simple linear regression analysis showed significant associations between the level of CA-II and egg laying rate from 16 week-old at 63 week-old WL-chicken (p < 0.01).</p> <p>Conclusions</p> <p>Developmental changes and sexual differences of CA-II concentration in WL-chicken erythrocytes were observed. The concentration of CA-II in the erythrocyte of WL-chicken was much higher than that in Araucana-chicken (p < 0.01).</p

    CLC-2 single nucleotide polymorphisms (SNPs) as potential modifiers of cystic fibrosis disease severity

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    BACKGROUND: Cystic fibrosis (CF) lung disease manifest by impaired chloride secretion leads to eventual respiratory failure. Candidate genes that may modify CF lung disease severity include alternative chloride channels. The objectives of this study are to identify single nucleotide polymorphisms (SNPs) in the airway epithelial chloride channel, CLC-2, and correlate these polymorphisms with CF lung disease. METHODS: The CLC-2 promoter, intron 1 and exon 20 were examined for SNPs in adult CF dF508/dF508 homozygotes with mild and severe lung disease (forced expiratory volume at one second (FEV1) > 70% and < 40%). RESULTS: PCR amplification of genomic CLC-2 and sequence analysis revealed 1 polymorphism in the hClC -2 promoter, 4 in intron 1, and none in exon 20. Fisher's analysis within this data set, did not demonstrate a significant relationship between the severity of lung disease and SNPs in the CLC-2 gene. CONCLUSIONS: CLC-2 is not a key modifier gene of CF lung phenotype. Further studies evaluating other phenotypes associated with CF may be useful in the future to assess the ability of CLC-2 to modify CF disease severity

    Association between expression of the Bone morphogenetic proteins 2 and 7 in the repair of circumscribed cartilage lesions with clinical outcome

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    <p>Abstract</p> <p>Background</p> <p>Although there is much known about the role of BMPs in cartilage metabolism reliable data about the <it>in vivo </it>regulation in natural and surgically induced cartilage repair are still missing.</p> <p>Methods</p> <p>Lavage fluids of knee joints of 47 patients were collected during surgical therapy. 5 patients had no cartilage lesion and served as a control group, the other 42 patients with circumscribed cartilage defects were treated by microfracturing (19) or by an Autologous Chondrocyte Implantation (23). The concentrations of BMP-2 and BMP-7 were determined by ELISA. The clinical status was evaluated using the IKDC Score prior to and 1 year following the operation.</p> <p>Results</p> <p>High level expression in the control group was found for BMP-2, concentrations of BMP-7 remained below detection levels. No statistical differences could be detected in concentrations of BMP-2 or BMP-7 in the lavage fluids of knees with cartilage lesions compared to the control group. Levels of BMP-7 did not change after surgical cartilage repair, whereas concentrations of BMP-2 statistically significant increased after the intervention (p < 0.001). The clinical outcome following cartilage regenerating surgery increased after 1 year by 29% (p < 0.001). The difference of the IKDC score after 1 year and prior to the operation was used to quantify the degree of improvement following surgery. This difference statistically significant correlated with initial BMP-2 (R = 0.554, p < 0.001) but not BMP-7 (R = 0.031, n.s.) levels in the knee joints.</p> <p>Conclusions</p> <p>BMP-2 seems to play an important role in surgically induced cartilage repair; synovial expression correlates with the clinical outcome.</p
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