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61.
Angiogenesis in Vulvar Intraepithelial Neoplasia   总被引:1,自引:0,他引:1  
Vulvar intraepithelial neoplasia (VIN) has been reported to be a precursor of invasive vulvar cancer. Switching to the angiogenic phenotype is considered a key step in tumor growth. Microvessel density (MVD) and vascular endothelial growth factor (VEGF), a highly angiogenic peptide, are important parameters of tumor angiogenesis. Forty-three histologic slides with 38 VIN I–III lesions were immunohistochemically stained for factor VIII-related antigen (F8-RA) and 44 slides with 37 VIN I–III for VEGF, since F8-RA reliably highlights tumor microvessels. Determination of MVD and VEGF expression was done by counting microvessels and VEGF-positive cells at a magnification of 200× and 400×. The highest concentration of F8-RA-stained MVD and VEGF expression was found at a small subepithelial area at the border of the VIN lesion to the stroma underneath but concentrations were low in all specimens of normal epithelium. High VEGF expression was significantly correlated to high MVD. For both MVD and VEGF expression the differences between VIN I and VIN III and between VIN II and VIN III were statistically significant (P< 0.0001). VIN III lesions are the clinical relevant precursors of invasive cancer of the vulva, as outlined by intense expression of VEGF protein and a highly dense network of microvessels underlying the dysplastic epithelium.  相似文献   
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Objective: The combination of transvaginal sonography and serum hCG measurement is reliable in the diagnosis of ectopic pregnancy (EP) in spontaneous pregnancies. In patients who became pregnant through IVF-ET, transfer of multiple embryos after IVF could be responsible for the different performance of these tests. We evaluated the discriminative capacity of transvaginal sonography in combination with hCG measurement in the diagnosis of EP after IVF-ET.

Design: Prospective cohort study.

Setting and Patient(s): Consecutive patients, pregnant through IVF-ET, who presented with clinically suspected EP.

Intervention(s): Transvaginal sonography, serum hCG measurement at 6, 9, and 15 days after ET and after a negative transvaginal sonography.

Main Outcome Measure(s): Ectopic pregnancy confirmed at laparoscopy.

Result(s): Between September 1993 and May 1996, 86 women were included in the study, of whom 24 had an EP. Transvaginal sonography identified 46 intrauterine pregnancies and 5 EPs, but serum hCG could not diagnose EPs in patients in whom transvaginal sonography did not show a gestational sac. Serum hCG measurement 9 days after ET could identify pregnancy failure with 100% specificity at a cut-off value of 18 IU/L, but it could not identify patients with EP with enough certainty to justify immediate treatment.

Conclusion(s): We recommend single serum hCG measurement 9 days after ET to discriminate between viable and nonviable pregnancies. Transvaginal sonography can be postponed until 5 weeks after ET, except for patients with abdominal pain and/or vaginal bleeding, or patients with a serum hCG level of <18 IU/L.  相似文献   

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BACKGROUND AND PURPOSE: In 1990 the skin source measuring bridge was proposed as a tool to measure (1) the distance between the interstitial implant and the overlying skin during brachytherapy boost treatment as well as (2) the distances between the lateral source end and the exit point of the guide needle. The present study reports on the clinical experience using the source skin measuring bridge with respect to incidence and grade of teleangiectasia, and their relation to source skin distances and doses. PATIENTS AND METHODS: Two hundred and twenty-two breast cancer patients (229 breasts) treated between 1983 and 1996 with breast conserving therapy including a brachytherapy boost were scored on the occurrence of teleangiectasia. The minimum distance between the sources (above implant and laterally) and the skin surface were measured. RESULTS: If no bridge was used the appearance of teleangiectasia in the epiderm above the implant is 77, 63 and 50% for boost doses of 25, 20 and 15 Gy, respectively. For brachytherapy boost doses of 25 and 20 Gy and distances smaller than 10mm between the implant and the overlying epiderm, as determined with the skin source measuring bridge, the appearance of teleangiectasia was 78 and 46%, respectively. When respecting provisional dosimetry to spare the skin for a boost dose of 15 Gy, resulting in distances between 10 and 15 mm for the implant overlying skin and distances between 5 and 10 mm for the lateral skin, teleangiectasia can be reduced to a minimum (6.3% above and 3.3% laterally). While in a univariate analysis several parameters (use of the bridge, boost dose, boost modality, external beam therapy modality) were predictive factors, the use of the bridge remained the only significant variable in a multivariate analysis. CONCLUSIONS: The skin source measuring bridge reduces teleangiectasia after interstitial brachytherapy boost treatment. A hypothesis made previously relating teleangiectasia and source skin distances was verified and extended. Even when 3D planning is used, the bridge allows for a provisional calculation of the security margins between source positions and the skin at the time of BT implantation to assure a correct needle positioning from the beginning, instead of correcting dwell times later on to avoid unnecessary high skin doses.  相似文献   
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BackgroundThe question of how to deal with B3 lesions is of emerging interest.MethodsIn the breast diagnostics of 192 patients between 2009 and 2016, a minimally invasive biopsy revealed a B3 lesion with subsequent resection. This study investigates the malignancy rate of different B3 subgroups and the risk factors that play a role in obtaining a malignant finding.ResultsThe distribution of B3 lesions after minimally invasive biopsy was as follows: atypical ductal hyperplasia (ADH), 7.3%; flat epithelial atypia (FEA), 7.8%; lobular neoplasia (LN), 7.8%; papilloma (Pa), 49.5%; phylloidal tumour (PT), 8.9%; radial sclerosing scar (RS), 3.1%; mixed findings, 10.4%; and other B3 lesions, 5.2%. Most B3 lesions were detected by stereotactic vacuum-assisted biopsy (44.3%), 36.5% by ultrasound-assisted biopsy, and 19.3% by magnetic resonance imaging-assisted biopsy. Most B3 lesions (55.2%) were verified by surgical resection, whereas 30.7% were downgraded to a benign lesion. About 14.1% of the cases were upgraded to malignant lesions, 9.4% to ductal carcinoma in situ and 4.7% to invasive carcinoma. In relation to individual B3 lesions, the following malignancy rates were found: 28.6% (ADH), 13.3% (FEA), 33.3% (LN), 12.6% (Pa), 5.9% (PT), and 0% (RS). The most important risk factor was increasing age. Postmenopausal status was considered an increased risk for an upgrade (p = 0.015). A known malignancy in the ipsilateral breast was a significant risk factor for a malignant upgrade (p = 0.003).ConclusionIncreasing knowledge about B3 lesions allows us to develop a “lesion-specific” therapy approach in the heterogeneous group of B3 lesions, with follow-up imaging for some lesions with less malignant potential and concordance with imaging or further surgical resection in cases of disconcordance with imaging or higher malignant potential.  相似文献   
68.
The Mediterranean diet (MD) is known to be one of the healthiest dietary patterns. Despite the significance of a healthful diet during the early stage of life, data for young individuals indicate that nutrition problems are common. This cross-sectional study aimed to determine parental factors associated with MD adherence in children and adolescents living in the Mediterranean region in Croatia. In total, 2623 children aged 2 to 18 years and their parents participated in this study. Data were collected during the period from September 2021 to February 2022 by using an anonymous questionnaire. We used KIDMED and MEDAS questionnaires for assessing MD adherence in young individuals and their parents, respectively. To assess the association of children’s MD adherence categories with the parental predictors, we performed multivariate multinomial logistic regression. Results showed that the children of parents with a low MD adherence are much more likely to have poor MD adherence than good (OR = 47.54 (95% C.I 18.24, 123.87), p < 0.001) or average (OR = 5.64 (95% C.I 3.70, 8.6), p < 0.001) MD adherence. Further, children of fathers with higher BMI (OR = 1.035 (95% C.I 1.0, 1.071)) and those who do not live with both parents (OR = 1.703 (95% C.I 0.994, 2.916), p = 0.053) are more likely to have poor MD adherence than good MD adherence. These results indicate that interventions focusing on enhancing the quality of both parents’ diets could effectively improve their children’s eating habits.  相似文献   
69.
Timely follow‐up for positive cancer screening results remains suboptimal, and the evidence base to inform decisions on optimizing the timeliness of diagnostic testing is unclear. This systematic review evaluated published studies regarding time to follow‐up after a positive screening for breast, cervical, colorectal, and lung cancers. The quality of available evidence was very low or low across cancers, with potential attenuated or reversed associations from confounding by indication in most studies. Overall, evidence suggested that the risk for poorer cancer outcomes rises with longer wait times that vary within and across cancer types, which supports performing diagnostic testing as soon as feasible after the positive result, but evidence for specific time targets is limited. Within these limitations, we provide our opinion on cancer‐specific recommendations for times to follow‐up and how existing guidelines relate to the current evidence. Thresholds set should consider patient worry, potential for loss to follow‐up with prolonged wait times, and available resources. Research is needed to better guide the timeliness of diagnostic follow‐up, including considerations for patient preferences and existing barriers, while addressing methodological weaknesses. Research is also needed to identify effective interventions for reducing wait times for diagnostic testing, particularly in underserved or low‐resource settings. CA Cancer J Clin 2018;68:199–216 . © 2018 American Cancer Society .  相似文献   
70.
Although the chromosome 18 alpha-satellite probe is considered to have a very low polymorphism rate, the routine use of this probe in prenatal diagnosis revealed rare variants in size and copy number of these sequences. A polymorphic signal was detected in preimplantation genetic diagnosis (PGD) for aneuploidy, in a patient with repeated early miscarriages. A third small signal of chromosome 18 alpha-satellite probe was observed in two of four evaluated embryos. Hybridization to the woman's metaphasic lymphocytes revealed that the small signal was localized in the pericentromeric region of chromosome 1. Reanalysis of blastomeres with telomeric probes for chromosome 18q confirmed the presence of only two copies of chromosome 18. Options for verifying PGD analysis results, to prevent misdiagnosis in cases of suspected polymorphism, are discussed. Although some authors speculate about a possible role of heterochromatin polymorphism in infertility, this rare polymorphism of 18 alpha-satellite sequences is in itself probably a normal variant. This is the third report of a cross-hybridization of the chromosome 18 alpha-satellite probe and the first report of the localization of the polymorphic 18 alpha-satellite signal to chromosome 1.  相似文献   
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