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21.
OBJECTIVE: There is an increasing evidence that genetic factors play a role in the etiology of malignant tumors. Mutations of BRCA1 and BRCA2 genes are responsible for an increased risk of ovarian cancer. The role of mutations in NOD2 gene in this type of neoplasm is still under investigation. THE AIM: The aim of this study was to determine: 1. incidence of NOD 2 3020insC constitutional mutation in a group of consecutive women with ovarian cancer, 2. risk of developing ovarian cancer in patients with NOD2 gene mutation, 3. clinical and pathological features of ovarian cancer in NOD2 gene mutation carriers. PATIENTS AND METHODS: Clinical and pathological data were collected from 257 non-selected patients with primary epithelial ovarian cancer. The researches identified NOD2 3020insC gene mutation. On the basis of patient source documentation we obtained the data concerning the age of patients at diagnosis, histopathological recognition, FIGO stage and morphological grade G. RESULTS: 19 out of 257 women were identified with germ-line 3020insC mutation of NOD2 gene (7.39%). An increased risk of ovarian cancer in NOD2 mutation carriers was not revealed (OR=1.01; p=0.928; 95% Cl=0.61-1.66). The mean age at diagnosis of patients with NOD2 mutation was 54.8 (SD=9.9), while for non-carriers it was 53.2 (SD=10.2). The difference between these frequencies was statistically irrelevant (p=0.550). Clinical and pathological profile of ovarian cancer was made. We assessed the following features: age at disease onset, histopathology, FIGO stage and morphological grade G. For NOD2 mutation carriers no statistically significant features of ovarian cancer were revealed. CONCLUSION: 1. Despite high frequency of constitutional mutations occurrence in NOD2 gene in women with ovarian cancer, genetic testing seem not to be justified in all women diagnosed with this disease. 2. Due to a lack of increased risk of ovarian cancer in NOD2 gene mutation carriers, proceedings for them may not differ from recommendations for general population. 3. It is difficult to determine characteristic clinical and pathological features of ovarian cancer for NOD2 gene mutation carriers.  相似文献   
22.
OBJECTIVES: The demand for genetic amniocentesis in case of young pregnant women has significantly increased due to various new indications. Moreover, nowadays a growing number of women aged > or =35, who required genetic amniocentesis, get pregnant The aim of the following study has been to compare the course of the pregnancy, the delivery and the condition of the newborn in two groups of patients: 18-34 years old and > or =35 years old. MATERIAL AND METHODS: 783 women underwent the procedure of amniocentesis at the Department of Obstetrics of Medical University of Gdansk in 1996-2003. A group of 540 women, who answered the questionnaire about the course of the pregnancy and the delivery after the procedure, has been isolated. RESULTS: Fetal loss occurred in 2 cases (1.6%) in the group of the younger women and in 8 cases (0.8%) in the group of > or =35 year-olds (p=0.84). There was no statistically significant difference between younger and older patients when comparing complications after the procedure in the first three weeks following amniocentesis: spotting, bleeding, leakage of amniotic fluid. Frequency of late complications such as gestational diabetes mellitus, pregnancy induced hypertension and urinary tract infections were comparable in both age groups women. Cesarean section has been more frequently performed in case of the older women than in the group of younger patients, with statistical difference p=0.003. In most cases (33.9%) it has been an elective cesarean section, performed due to advanced maternal age rather than any obstetric cause. Frequency of pneumonia and the number of respiratory infections in the newborns have been comparable in both groups. CONCLUSIONS: Prenatal invasive diagnosis has no influence on frequency of complications during pregnancy and delivery in the group of women less than 35 years old and more than 35 years old.  相似文献   
23.
DNA adducts, one of genetic damages markers, precede and finally can lead to oncogenic mutations. They appear in genome as a result of DNA bases damages caused by various and numerous environmental factors eg. ultraviolet light, ionic radiation, toxins and also endogenic substances, for example estrogens. It is believed that the creation of DNA adducts is a necessary but insufficient process for the neoplastic transformation of the cell. The following review presents concise knowledge about the DNA adducts creation and their sequels served in healthy and cancerous tissues of the female genital organs, on the base of the available data.  相似文献   
24.
A diagnostic procedure in the medical treatment of middle hydrothorax at haemodynamically efficient fetus has been presented in the research. Container of the liquid in the fetal thorax has been observed since the eleventh week of pregnancy. Infection by TORCH viruses has been excluded and typical 46,XX female karyotype has been found in the cytogenic test. A liquid in the pericardial sack (without any sings of the fetal heart defect) was observed in the ECHO examination from 23 to 37 week of pregnancy. Cesarean section was made after 37 weeks of pregnancy and the new-born baby was found to be in good condition, with body mass of 3130g and 9 points in the Apgar scale. The child cardiologist did not diagnose any heart disorders. Awaiting attitude, while monitoring the state of the fetus, seems to be the right course of action in cases of haemodynamically efficient fetus with isolated hydrothorax.  相似文献   
25.
26.
OBJECTIVE: The purpose of the research was to provide a review of the efficacy of the TVT-O technique for the surgical treatment of stress urinary incontinence (SUI) and to assess surgical and postsurgical complications related to this technique. STUDY DESIGN: An initial assessment was carried out on 44 women who underwent TVT-O surgery between 16 September 2004 and 1 February 2005. The follow-ups after 3 and 12 months were attended by 37 and 35 patients, respectively. All 44 patients were included for the statistical estimation of intra- and postoperative complications, whereas improvement in the quality of life was assessed only in those patients who came for a follow-up visit. To assess the efficacy of the treatment, the participants were surveyed using the King questionnaire on the day preceding surgery and during a follow-up visit 3 and 12 months after surgery. The participants whose scores from the two questionnaires changed > or =90% were deemed to be cured. A considerable improvement in quality of life was recorded when the score was 89-75%. With scores of 74-50%, there was a reduction in SI symptoms. However, when the score was 50-0%, no improvement in quality of life was reported, and in participants with scores <0% the quality of life deteriorated. Statistical analysis was carried out using the Statistical Package for Social Sciences (SPSS) V. 10.0, with the Spearman correlation and Chi-squared tests. The results were considered statistically significant when P<0.05. RESULTS: After 12 months, total cure was achieved in 15 participants (42.8%), significant improvement was noted in 6 (17.1%), SUI symptoms abated in 4 (11.4%), no improvement was noted in 7 (20%), and quality of life deteriorated in 3 (8.7%). CONCLUSION: TVT-O surgery is an efficient and reasonably safe method of SUI treatment in women. The ease of use, short duration of surgery and hospitalisation, minor postsurgical discomfort and a small proportion of complications make this method acceptable to patients. With regard to the results of treatment, additional patients should be analysed for a longer period of time.  相似文献   
27.
28.
Tetrahedrites, due to their promising thermoelectric properties, are one of the materials being investigated for use in thermoelectric generators. One problem is the lack of n-type tetrahedrites, which would be beneficial for the design of tetrahedrite thermoelectric modules. Preliminary theoretical studies have shown that elements from groups I and II can be introduced into the structural voids of tetrahedrite, acting as donor dopants, and should enable n-type conductivity. Therefore, in this work, an attempt was made to obtain and study magnesium-doped tetrahedrites. A series of samples, MgxCu12Sb4S13, with different magnesium contents were obtained and their phase and chemical compositions were characterized. It was observed that the structural changes occurring upon doping indicate that Mg atoms are likely to be embedded in the structural voids. The experimental studies have been supported by electronic structure calculations indicating that the most likely location of Mg is in the structural voids at the 6b Wyckoff position. Seebeck coefficient and resistivity measurements showed that doping with Mg reduces the concentration of holes, which is consistent with the predicted donor character of the dopant. However, the introduction of magnesium in sufficient amounts to achieve n-type conductivity was not successful.  相似文献   
29.
Due to their properties, porous sliding bearings are considered to be maintenance-free, which means that no lubrication is required during operation. Their design enables operation at low rotational speeds with high load. Another effect of this bearing design is the lubrication continuity in the tribological pair. In this study, the selected tribological properties (such as load capacity and permeability) of new-generation iron porous bearings with boron nitride powder were experimentally investigated. Tests were carried out under various conditions, using unique test apparatus. The addition of 3% (weight) of hexagonal boron nitride (hBN) significantly increased the load capacity of tested porous bearings in comparison to the same standard bearings containing 2.5% copper. The obtained pgr·v rating reached almost 7 MPa, which is a value almost three times higher than the requirements for this type of bearing. It is worth emphasizing that such a result was obtained despite a noticeable deterioration in the air and oil permeability of the bearing.  相似文献   
30.
The article presents research on the potential use of organometallic compounds with the addition of antimony (III) oxide Sb2O3 as a coating additive that will make coatings susceptible to electroless metallization after prior surface irradiation with 193 nm wavelength laser radiation and a different number of laser pulses. The surface modification and activation effects were assessed by optical-imagining as well as by scanning electron microscopy (SEM) with energy dispersive analysis (EDX). It was found that the presence of Sb2O3 in the coating made it possible to reduce the content of the copper complex, causing an intensive surface ablation, resulting in the formation of a conical structure with a higher content of metallic copper nuclei.  相似文献   
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