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1.
Objectives:To reassess the long-term camouflage effects of resin infiltration (Icon, DMG, Hamburg, Germany) of white spot lesions (WSL) and sound adjacent enamel (SAE) achieved in a previous trial. The null hypothesis was tested that there were no significantly different CIE-L*a*b*-ΔE-values between WSL and SAE areas of assessment after at least 24 months (T24) compared to those at baseline (T0).Materials and Methods:Of twenty subjects who received previous resin infiltration treatment of nteeth = 111 nonrestored, noncavitated postorthodontic WSL after multibracket treatment during a randomized controlled trial and were contacted 20 months after baseline, eight subjects (trial teeth nteeth = 40; m/f ratio 1/7; age range (mean; SD) 12–17 [15.25; 2.12] years); response rate: 40%) were available for follow-up after at least 24 months (T24). CIE-L*a*b* differences between summarized color and lightness values (ΔEWSL/SAE) of WSL and SAE were assessed using a spectrophotometer and compared to baseline data assessed prior to infiltration (T0), and those after 6 (T6), and 12 (T12) months using paired t tests at a significance level of α = 5%.Results:T24 assessments were performed after a mean 33.86 (SD: 8.64; Min: 24; Max: 45) months following T0. Mean (SD) ΔEWSL/SAE units of available teeth were 8.76 (5.33) at baseline; 5.5 (2.75) at T6; 5.2 (2.41) at T12; and 5.57 (2.6) at T24. Comparisons of T6, T12, and T24 with T0 yielded highly significant differences, whereas T6–T24 and T12–T24 differences were found to be not significant.Conclusions:Assimilation of infiltrated WSL to the color of adjacent enamel by resin infiltration is considered to be suitable for the long-term improvement in the esthetic appearance of postorthodontic WSL. 相似文献
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Marc Bischof MD Jürgen Debus Klaus Herfarth Thomas Muley Jutta Kappes Konstantina Storz Hans Hoffmann 《Strahlentherapie und Onkologie》2007,183(12):679-684
PURPOSE: To analyze the effectiveness of surgery and chemotherapy with or without radiotherapy in the management of limited small cell lung cancer (LSCLC) in stages I and II. PATIENTS AND METHODS: 39 patients (median age 62 years) with LSCLC in stages pT1 or pT2 and pN0 or pN1 (stages IA-IIB) who had a tumor resection and systematic lymph node dissection were reviewed retrospectively. The median follow-up period was 29 months. 35 patients (90%) received a median of four cycles of a platinum-containing chemotherapy postoperatively. 16 patients (41%) received an adjuvant thoracic radiotherapy (TRT, median 50 Gy); 21 patients (54%) received a prophylactic cranial irradiation (PCI, median 30 Gy). RESULTS: The median overall survival for all patients was 47 months, resulting in actuarial 1-, 3-, and 5-year survival rates of 97%, 58%, and 49%, respectively. Distant metastases were found in 13 patients (33%) after a median of 16 months. Patients who received an adjuvant TRT showed a trend toward improved thoracic recurrence-free survival (p = 0.06) and improved overall survival (p = 0.07) compared to those treated with surgery and chemotherapy only. Brain metastasis-free survival (p = 0.01) and overall survival (p = 0.01) were improved significantly in patients who received a PCI. CONCLUSION: Surgical tumor resection may be considered for carefully selected patients. Adjuvant chemotherapy and PCI are recommended for all patients. Adjuvant TRT is currently used in patients with positive lymph nodes (pN1), because the probability of a subclinical involvement of the mediastinal lymphatic system appears to be increased in these patients. 相似文献
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Zusammenfassung GRUNDLAGEN: Die endoskopische thorakale Sympathektomie (ETS) existiert seit 60 Jahren als effektive Therapie der primären Hyperhidrose. Nach wie vor gibt es in der medizinischen Welt teils Vorbehalte, teils Unwissen über die Methode selbst, ihre Erfolgs- und Komplikationsraten sowie Nebenwirkungen. METHODIK: Nach Einführung in die Symptome und Behandlung der primären Hyperhidrose (konservativ und chirurgisch) werden Operationsmethoden und Langzeitergebnisse der ETS-Operation vorwiegend anhand der Daten aus der eigenen Abteilung präsentiert. ERGEBNISSE: Von 1965–2001 wurden 734 Sympathikotomien (ETS2–4) und bis 2003 weitere 103 Sympathikusblockaden (ESB4) bei Patienten mit primärer palmarer und axillärer Hyperhidrose durchgeführt. Die Konversionsrate betrug 0,1 %. Seit Einführung der Video-Thorakoskopie 1991 trat kein postoperatives Horner-Syndrom auf (zuvor 2,2 %), Drainage-pflichtige Pneumothoraces waren in 1,1 % zu verzeichnen. Nach einem medianen Follow-up von 16 Jahren waren 93 % der Extremitäten trocken, 5 % fast trocken und 2 % feucht. Nebenwirkungen traten in Form von kompensatorischem Schwitzen am Stamm (55 % insgesamt, davon 5 % stark) und gustatorischem Schwitzen (33 %) auf. Seit Einführung der limitierten Sympathikusblockade auf Höhe T4 (ESB4) konnte (bei naturgemäß kurzer Nachbeobachtungszeit) das kompensatorische Schwitzen auf 8,5 % und das gustatorische Schwitzen auf 2,1 % gesenkt werden. Mit dem postoperativen Ergebnis waren 100 % der Patienten nach ESB4 zufrieden, nach ETS2–4 waren 80 % zufrieden, 14 % teilweise zufrieden und 6 % unzufrieden (meist wegen starken kompensatorischen Schwitzens). SCHLUSSFOLGERUNGEN: Die ETS-Operation bietet hohe langfristige Erfolgsraten bei niedrigen Komplikationsraten. Patienten sollten über die zu erwartenden Nebenwirkungen genau aufgeklärt werden, für unzufriedene Patienten mit starkem kompensatorischem Schwitzen besteht nun die Möglichkeit der thorakoskopischen Klip-Entfernung. 相似文献
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The rate of development and time of transfer play different roles in influencing the viability of human blastocysts 总被引:7,自引:6,他引:1
Shoukir Y; Chardonnens D; Campana A; Bischof P; Sakkas D 《Human reproduction (Oxford, England)》1998,13(3):676-681
Improved embryo culture protocols now render more feasible the possibility
of obtaining human blastocysts after in-vitro fertilization. In this study
we present: (i) results of blastocyst development from supernumerary
embryos after co-culture on green monkey kidney epithelial cells and (ii)
pregnancy rates after transfer of frozen blastocysts. In addition, we have
examined the influence of the day of blastocyst freezing and the day of
transfer after the luteinizing hormone (LH) peak on pregnancy and
implantation rates. Of 423 supernumerary embryos, 200 developed to the
blastocyst stage (47.3%). By days 5 and 6, 67% of the blastocysts had
reached the blastocyst stage, and were frozen, compared to 28.5% by day 7.
When we compared the cases where only blastocysts frozen on days 5 and 6
were transferred compared to those frozen and transferred on or after day 7
the pregnancy rates were 7/18 (38.9%) and 1/16 (6.2%) respectively. In
contrast, when we examined the influence of the day of transfer we found
that pregnancies were established from day 5 up to day 9 post LH peak.
Based on these results, we suggest that every attempt should be made to
increase the development rate of supernumerary embryos to the blastocyst
stage, as it appears that the quality of blastocysts transferred, as shown
in this study by rate of development, plays a more crucial role than the
timing of transfer.
相似文献
7.
Normative values of bone parameters of children and adolescents using digital computer-assisted radiogrammetry (DXR). 总被引:2,自引:0,他引:2
Ansgar Malich Martin G Freesmeyer Hans-Joachim Mentzel Dieter Sauner Joachim Boettcher Alexander Petrovitch Werner Behrendt Werner A Kaiser 《Journal of clinical densitometry》2003,6(2):103-111
PURPOSE: To verify whether estimation of bone mineral density (BMD) using digital X-ray radiogrammetry (DXR) is possible on children and to determine normative values of both such a DXR-BMD estimate and a corresponding metacarpal index (DXR-MCI) on. PATIENTS AND METHODS: In retrospect, X-rays were selected of the hands of 200 healthy Caucasian children (120 boys and 80 girls, aged 4-18 yr). The involved children were selected among a larger group of children submitted to the surgical department of our institute for evaluation of a suspected fracture after an occurred trauma. All children with a verified fracture or a chronic bone-related disease, including bone age retardation or acceleration, were excluded from the study. Furthermore, only conventional X-rays with the same film and capture parameters were included. The images were scanned and analyzed using the Pronosco X-posure system V.2 (Sectra Pronosco, Denmark). DXR-BMD, DXR-MCI, and a porosity index (DXR-PI) were automatically calculated using the midshafts of the metacarpals II-IV. Mean values of DXR-BMD and DXR-MCI were calculated separately for girls and boys in 2-yr intervals. RESULTS: In the present study the system has been demonstrated to be capable of calculating DXR-BMD from conventional X-rays of the hand from children down to approx 6 yr of age. This ability depended somewhat on the diameter and the length of the involved metacarpals. The success rate was higher for large bones than for small bones. The system succeeded in analyzing the images of 110 boys and 68 girls. Values of DXR-BMD were observed to increase with age from 0.40 g/cm2 to 0.62 g/cm2 in the male group and from 0.39 g/cm2 to 0.54 g/cm2 in the female group. Girls aged 11-12 yr had a higher DXR-BMD than did boys, corresponding to the earlier entry to puberty of girls. Standard deviations (SDs) reached values of up to 0.05 g/cm2. DXR-MCI increased with age from 0.36 to 0.47 for boys and from 0.34 to 0.49 for girls with a maximum SD of 0.06. The correlation between DXR-BMD and age was r=0.83 and r=0.84 for boys and girls, respectively. The corresponding correlations for DXR-MCI was lower, with observed correlations of r=0.63 (boys) and r=0.68 (girls), respectively, with p<0.01 in all cases. The DXR-PI did not reveal a significant correlation to age (r=-0.31 and r=0.04. respectively) and showed SDs marginally higher than the calculated mean values. CONCLUSION: The newly available DXR-methodology seems to offer the ability to determine DXR-BMD and DXR-MCI in children starting with a bone age of 6. This possibility may be of special relevance for children suffering from chronic bone diseases that require repeated X-rays of the hand (e.g. to determine bone age). The acquired normative data suggest that the measurements are of clinical value owing to low age-dependent variability (SDs) relative to an observed high increase with age. The clinical value of the porosity index (DXR-PI) remains uncertain and is limited owing to a high inter-individual variability. 相似文献
8.
P A Brioschi P Bischof C Delafosse F Krauer 《International journal of cancer. Journal international du cancer》1991,47(3):376-379
The serum concentration of squamous-cell carcinoma antigen (SCC-A), a subfraction of tumour antigen, was determined by RIA from healthy donors (control group) and from patients with malignant cervical disease. Ninety-six percent (173/180) of the healthy patients had squamous-cell carcinoma antigen serum levels below 2 ng/ml. Ten of 70 (14.3%) patients with CIN III, 53.8% (34/62) of patients with invasive squamous-cell carcinoma stage I, 85.8% (30/35) with stage II and 96.5% (27/28) with stage III/IV had squamous-cell carcinoma antigen serum levels above 2 ng/ml. We observed that 22.5% (11/49) of patients with a tumour volume below 10 ml and 92.6% of patients with a tumour volume greater than 10 ml had squamous-cell carcinoma antigen levels above 2 ng/ml (p less than 0.005). SCC-A was correlated with recurrence or progressive disease in 90.0% of cases. Other risk factors such as depth of invasion, microscopic parametrial involvement, lymphatic and/or vascular space permeation and histological grade were not correlated with squamous-cell carcinoma antigen. Furthermore, this marker increased 4.3 +/- 2.7 months before clinical evidence of recurrence or progressive disease. We conclude that serial serum levels of squamous-cell carcinoma antigen provide a means for early detection of recurrence or progressive disease. This tumour marker might also be useful for monitoring the treatment effects and has some prognostic value. 相似文献
9.
Hans-Joachim Wallny Olaf Rtzschke Kirsten Falk Günther Hmmerling Hans-Georg Rammensee 《European journal of immunology》1992,22(3):655-659
DBA/2-derived mouse tumor cells were transfected with the H-2 Kb gene. Naturally processed minor histocompatibility (H) peptides were extracted from both transfected and non-transfected cells by acid elution, and were separated by high-performance liquid chromatography. Kb-restricted minor H epitopes corresponding to H-4b and mapki, both encoded by non-major histocompatibility complex genes of DBA/2, were readily detected by the respective cytotoxic T lymphocyte in peptides extracted from Kb-transfected, but not from non-transfected or Db-transfected cells. Titration experiments indicated at least 3000-fold less copies of correctly processed Kb-restricted epitopes in cells without Kb as compared to cells with Kb. Since we estimate the copy number of Kb-restricted H-4b epitopes in Kb-expressing transfectants to be less than 1000 per cell, the pool size of H-4b epitopes correctly processed in the absence of Kb should be less than 1/3 copy per cell. 相似文献
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