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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   
62.
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   

63.
64.
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   
65.
66.
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   
67.
Flavonoids are found universally in plants and act as free radical scavenging and chelating agents with antiinflammatory, antiischemic, vasodilating and chemoprotective properties. In this study, the antilipoperoxidative and cytoprotective effects of apigenin, baicalein, kaempferol, luteolin and quercetin against doxorubicin-induced oxidative stress were investigated in isolated rat heart cardiac myocytes, mitochondria and microsomes. After preincubation of cardiomyocytes with the test compounds for 1 h the cardiomyocytes were treated with the toxic agent, doxorubicin (100 micro M for 8 h). Cardiomyocyte protection was assessed by extracellular LDH and cellular ADP and ATP production. Cytoprotection was concentration dependent for baicalein > luteolin congruent with apigenin > quercetin > kaempferol. All test compounds had signi fi cantly better protective effects than dexrazoxan, an agent currently used for adjuvant therapy during anthracycline antibiotic therapy. In microsomes/mitochondria the IC(50) values of lipid peroxidation inhibition for quercetin, baicalein, kaempferol, luteolin, and apigenin were 3.1 +/- 0.2/8.2 +/- 0.6, 3.3 +/- 0.3/9.6 +/- 0.5, 3.9 +/- 0.3/10.1 +/- 0.8, 22.9 +/- 1.7/18.2 +/- 0.7, and 338.8 +/- 23.1/73.1 +/- 6.4 mM, respectively. The antilipoperoxidative activity of apigenin differed from its cytoprotective effects, but correlated with the free radical scavenging of 2,2-diphenyl-1-picrylhydrazyl radical and half peak oxidation potential (E(p/2)). Apigenin was the least effective of the flavonoids studied in all models except the cardiomyocyte model where its cardiomyocyte cytoprotective effect was comparable to other compounds.  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.
Dietary supplements used by women during menopause are usually based on plant extracts containing isoflavonoids, daidzein and genistein. Genistein is a known inhibitor of many enzymes, including thyroid peroxidase (TPO). In the thyroid follicle, genistein acts as its alternate substrate for the formation of genistein iodinated derivatives. The aim of this study was to search for daidzein- and genistein-iodinated derivatives in urine of isoflavonoid-supplemented women. Additionally, selected phytoestrogens, steroid and thyroid hormones before and after three months of phytoestrogen supplementation were estimated. Urinary levels of free phytoestrogen increased significantly after therapy. They ranged between 0.3–1600, 0.6–670 and 0–206 nmol/L for daidzein, genistein and S-equol, respectively. Monoiodinated derivatives of genistein were observed (0–504 pmol/L) in 60% of the investigated samples. Steroid and thyroid hormone levels were within the normal range and were not significantly altered. The presence of monoiodinated derivates in human urine confirmed that genistein and daidzein may enter human thyroid follicles and influence TPO. Since the levels of the free thyroid hormones were not affected, we propose that the use of phytoestrogen dietary supplements is not associated with the development of thyroid-gland disorders in subjects with adequate iodine intake.  相似文献   
70.
捷克作为欧洲内陆的议会共和制国家,实施强制保险模式以保障民众健康。导致人口死亡的主要疾病为缺血性心脏病、脑卒中和肺癌,而糖尿病、AD及COPD近年来发病率显著增加。捷克的传统医学包括巴赫花疗法、特异性免疫调节自我疗法、法国耳针治疗等。中医药在捷克具有一定的接受度,尤其是针灸已在神经性疾病中得到广泛应用。但中草药在捷克的使用受到限制,且中医药执业尚未合法化。建议深化多层次、多领域交流合作,并通过加强高水平中医药学位教育,加大中药与非药物疗法宣传和普及力度,推动中医药在捷克的发展。  相似文献   
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