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1.
Background: During labor, ephedrine is widely used to prevent or to treat maternal arterial hypotension and restore uterine perfusion pressure to avoid intrapartum fetal asphyxia. However, the effects of ephedrine on uterine blood flow have not been studied during uterine contractions. The purpose of the study was to assess the effects of ephedrine on uterine artery velocities and resistance index using the Doppler technique during the active phase of labor.

Methods: Ten normotensive, healthy parturients with uncomplicated pregnancies at term received intravenous ephedrine during labor to increase mean arterial pressure up to a maximum of 20% above their baseline pressure. Peak systolic and end-diastolic Doppler flow velocities and resistance indices were measured in the uterine artery before and immediately after administration of bolus intravenous ephedrine and after ephedrine washout. Umbilical and fetal middle cerebral arterial resistance indices and fetal heart rate were also calculated.

Results: After ephedrine administration, mean arterial pressure increased by 17 +/- 4%. End-diastolic flow velocity in the uterine artery at peak amplitude of uterine contraction was restored to 74% of the value observed in the absence of contraction. The systolic velocity was totally restored, and the uterine resistance index was significantly decreased, compared with the values in the absence of contraction. Between uterine contractions, ephedrine induced similar but less marked effects. Fetal hemodynamic parameters were not altered by ephedrine administration.  相似文献   

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Resumé Dans le but d'analyser les besoins d'une population en matière de dépistage des cancers, les attitudes, connaissances et comportements des femmes à propos des cancers du sein et du col utérin sont étudiées, auprès d'un groupe de consultantes tout venant de 3 centres de santé tunisiens (Kalaa-Kebira). Les résultats soulignent la nécessité d'informer la population concernant les facteurs de risque de ces maladies, particulièrement en ce qui concerne le cancer du sein, (1er cancer de la femme en Tunisie) mais surtout sur les signes d'appel et les moyens de dépistage disponibles. Le rôle des professionnels de la santé, plus du généraliste et de la sage-femme que du gynécologue apparait clair auprès des consultantes. L'éducation individuelle et de masse doit cependant aller de pair avec une sensibilisation et une formation des professionnels de la santé eux-mêmes en matière de dépistage.
Knowledges, attitudes and behaviors of Tunisian women about gynaecologic cancers
Summary With the aim to analyze population needs in the field of cancer screening (cervical and breast cancer), attitudes, behaviors and knowledge of a tunisien women group of health service user's were studied. Results clearly demonstrate the necessity to inform the concerned population about risk factors particularly concerning breast cancer (the most frequent cancer in Tunisia) but also early symptoms and available screening methods. This role is alloted to health professionals, more for general practitioners and midwives than for gynaecologists. Health education for women and groups, however, have to go hand in hand with training of health professionals in matter of test screening.

Kenntnisse, Haltung und Verhalten der tunesischen Frauen in Bezug auf gynäkologische Krebse
Zusammenfassung Haltung, Kenntnisse und Verhalten der Frauen gegenüber dem Brustkrebs und dem des Uterushalses wurden an Hand einer Patientinnengruppe in Tunesischen Gesundheitszentren (Kalaa-kebira) erlangt. Die Ergebnisse bestätigen die Notwendigkeit, die Bevölkerung über die Risikofaktoren dieser Krankheiten zu unterrichten, besonders was den Brustkrebs betrifft (den verbreitetsten Krebs bei Frauen in Tunesien), aber vor allem über die Krankheitsanzeichen und die verfügbaren diagnosemethoden. Die Rolle der Gesundheitskräfte, insbesondere die des Allgemeinarztes und der Hebamme, noch vor derjenigen des Frauenarztes, sind den Patientinnen verständlich. Die individuelle sowie die massenhafte Gesundheitserziehung muss Hand in Hand gehen mit einer Sensibilisierung und einer Ausbildung des Gesundheitspersonals in Sachen Diagnosemethoden.
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Comparative genomic hybridization on a microarray (microarray-CGH) allows to detect genomic chromosome imbalances. In order to assess its value to detect small chromosome imbalances observed in a clinical setting, using a DNA chip available commercially (Spectral Genomics, Houston, Texas, USA), we studied the DNA of 9 patients carrying a well characterized chromosome imbalance and the DNA of 11 patients where cytogenetic techniques such as high resolution banding karyotype, FISH using subtelomeric probes and comparative genomic hybridization on metaphase chromosomes conclude to a normal and/or balanced karyotype. A result was obtained for 19/20 patients. Failure of hybridization was observed for one patient. For all the other cases the sex of patients was correctly identified. Microarray-CGH was able to correctly diagnose the chromosome imbalance in 6/8 patients carrying such a defect i.e 9/11 imbalances (deletion or duplication) were detected. No chromosome imbalance was observed in 11 patients considered normal and/or balanced using cytogenetic techniques. Several clones were found to be polymorphic and required FISH studies to eliminate duplication or deletion. In conclusion, we think that this commercially available DNA chip might be useful to screen for chromosome imbalances. However, technical improvements are still necessary before using it in a clinical setting. Also, further studies are necessary to assess its sensitivity and specificity.  相似文献   
5.
Peeva E  Zouali M 《Immunology letters》2005,101(2):123-143
Pathogenic autoimmunity requires a combination of inherited and acquired factors. In as much as hormones influence the sexual dimorphism of the immune system, it is possible that they can initiate or accelerate an autoimmune process, and contribute to gender-biased autoimmune disorders. Not only natural hormones, but also endocrine disruptors, such as environmental estrogens, may act in conjunction with other factors to override immune tolerance to self-antigens. In lupus, murine and human studies demonstrate that female sex hormones are implicated in disease pathogenesis. In the B cell compartment, both prolactin and estrogen are immunomodulators that affect maturation, selection and antibody secretion. Their impact may be based on their capacity to allow autoreactive B cells to escape the normal mechanisms of tolerance and to accumulate in sufficient numbers to cause clinically apparent disease. Both hormones lead to the survival and activation of autoreactive B cells, but they skew B cell maturation towards different directions, with prolactin inducing T cell-dependent autoreactive follicular B cells and estrogen eliciting T cell-independent autoreactive marginal zone B cells. Differential modulation of the cytokine milieu by hormones may also affect the development and activation of specific mature B cell subsets. This novel insight suggests that targeted manipulation of these pathways may represent a promising avenue in the treatment of lupus and other gender-biased autoimmune diseases.  相似文献   
6.
Genotype-phenotype correlation in women with an abnormal phenotype associated with a duplication of the long arm of the X chromosome remains unclear. We report on prenatal diagnosis and follow-up of a girl with an Xq duplication and dysmorphic features. The abnormal phenotype included growth retardation, hypotonia, and nystagmus. In order to improve the resolution of the cytogenetic analysis, we used both conventional and array-based comparative genomic hybridization to perform a global molecular cytogenetic analysis of the genome. These molecular cytogenetic analyses showed a direct duplication Xq21.1 --> q25 without other chromosomal abnormalities. This duplication was originating from the paternal X chromosome. Moreover, a skewed X-inactivation pattern was observed leading to a partial functional disomy of the chromosomal region Xq21.1q25. This report and review of the literature suggest that functional disomy for chromosome X could explain the abnormal phenotype. In prenatal diagnosis, this can have implication for patient management and genetic counseling.  相似文献   
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Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete.  相似文献   
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Hydatidiform moles (HM) are characterized by an abnormal proliferating trophoblast with a potential for a malignant transformation. Similar to other human tumors, trophoblastic pathogenesis is likely a multistep process involving several molecular and genetic alterations. The study was performed to investigate the expression patterns of c-erbB-2 and Bcl-2 oncoproteins, p53, p21WAF1/CIP1 and p63 tumor suppressor proteins and Ki-67 cell proliferation marker in HM.We conducted a retrospective study of 220 gestational products, including 39 hydropic abortions (HA), 41 partial HM (PHM) and 140 complete HM (CHM). The expression of c-erbB-2, Bcl-2, p53, p21WAF1/CIP1, p63 and Ki-67 was investigated by immunohistochemistry on archival tissues. c-erbB-2 expression was observed in three PHM and 10 CHM. Bcl-2 immunostaining was significantly higher in PHM (61%) and CHM (70.7%) compared with HA (7.7%, p?=? 0.001 and p?<? 0.0001, respectively). p53 expression was stronger in CHM (73.6%) compared with PHM (24.4%, p < 0.0001) and HA (12.8%, p < 0.0001). p21WAF1/CIP1 staining was observed as well in molar and non-molar gestations (p?>? 0.05). p63 immunoexpression was significantly described in CHM (85.7%) and PHM (78%) compared with HA (10.2%, p < 0.0001 and p = 0.0001, respectively). Ki-67 was significantly expressed in CHM (72.1%) compared with HA (46.2%, p = 0.005).Altered expression of Bcl-2, p53, p63 and Ki-67 reflects the HM pathological development. Immunohistochemical analysis is beneficial to recognize the HM molecular and pathogenic mechanisms. Furthermore, it could serve as a useful adjunct to conventional methods for refining HM diagnosis.  相似文献   
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