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BACKGROUND: The prevalence of menstrual pain in Western societies is relatively high and has been shown to be related to many factors (e.g. age, menarche age, parity, menstrual cycle regularity, cigarette smoking, dietary habits). However, less data are available for traditional societies, within which there are, presumably, not as many potentially disturbing factors that could influence menstrual symptoms as in Western societies. AIM: The study seeks to determine the prevalence of dysmenorrhoea, and the factors related to menstrual pains in women with natural fertility (i.e. without hormonal forms of contraception). SUBJECTS AND METHODS: 177 non-smoking women between 18 and 45 years of age living in one Mayan village (Yaxcaba, Yucatan, Mexico) were the subjects of this study. The method of logistic regression was used with the dichotomous dependent variable being the presence or absence of menstrual pain together with such independent variables as age, age at menarche, number of pregnancies, age when giving birth to the first child, the weight at interview and BMI. RESULTS: The general prevalence of the menstrual pains was 28%. There was only one variable influencing dysmenorrhoea, namely the age at which women give birth to their first children. Those mothers who gave birth to their first child at an earlier age (at mean age of 19.4 vs 21.1 years) had a lower prevalence of dysmenorrhoea. CONCLUSION: In the studied traditional society the main factor related to menstrual pain was the age at which woman first gave birth. It is hypothesized that an earlier start to reproductive life in some way decreases the sensitivity of the uterus to prostaglandins.  相似文献   
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Vascular endothelial growth factor-receptors (VEGF-Rs) are pivotal regulators of vascular development, but a specific role for these receptors in the formation of heart valves has not been identified. We took advantage of small molecule inhibitors of VEGF-R signaling and showed that blocking VEGF-R signaling with receptor selective tyrosine kinase inhibitors, PTK 787 and AAC 787, from 17-21 hr post-fertilization (hpf) in zebrafish embryos resulted in a functional and structural defect in cardiac valve development. Regurgitation of blood between the two chambers of the heart, as well as a loss of cell-restricted expression of the valve differentiation markers notch 1b and bone morphogenetic protein-4 (bmp-4), was readily apparent in treated embryos. In addition, microangiography revealed a loss of a definitive atrioventricular constriction in treated embryos. Taken together, these data demonstrate a novel function for VEGF-Rs in the endocardial endothelium of the developing cardiac valve.  相似文献   
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Laparoscopy was first performed at the turn of the century, but it was not until the introduction of laparoscopic cholecystectomy that the procedure became widely adopted by general surgeons. Since then, traditional open procedures, including cholecystectomy, exploratory laparotomy, colectomy, hernia repair, and appendectomy, are being widely performed laparoscopically. The advantages of laparoscopic surgery, including less postoperative pain due to smaller surgical incisions, shorter hospital stay, quicker return to preoperative activity, and superior cosmesis, resulted in widespread popularity with both surgeons and patients. In certain situations, the traditional method may be superior to the laparoscopic approach, as may be the case with laparoscopic hernia repair. It is difficult to justify converting a local, extraperitoneal, 45-minute, outpatient inguinal hernia repair in a virgin groin into a general anesthetic, transperitoneal, 2-hour plus, possibly inpatient laparoscopic procedure with the implantation of mesh. However, data may indicate that this operation does indeed have benefits. We must, therefore, carefully study such new operations. With the advent of a new surgical procedure, both surgeons and anesthesiologists must be familiar with the various complications unique to this technique. If recognized early, potentially life-threatening complications, including gas embolization and tension pneumothorax, can be corrected.  相似文献   
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B. Kasztelewicz, I. Jankowska, J. Paw?owska, J. Teisseyre, R. Grenda, M. Pronicki, K. Dzier?anowska‐Fangrat. Epstein–Barr virus DNA load in peripheral blood mononuclear cells and whole blood from pediatric transplant recipients.
Transpl Infect Dis 2011: 13: 471–479. All rights reserved Abstract: Monitoring of circulating Epstein–Barr virus (EBV) DNA in pediatric transplant patients has been shown to be useful in post‐transplant patient management. It still remains unclear which blood sample type is more suitable, and how EBV DNA levels in whole blood (WB) correlate with those in peripheral blood mononuclear cells (PBMCs). The aim of this study was to compare EBV DNA load in WB and PBMCs of pediatric transplant recipients. After liver, kidney, or combined liver–kidney transplantation, 172 matched WB and PBMCs samples were collected from 84 children (130 samples from 42 patients consisted of multiple collections). The EBV DNA level in PBMCs was determined by home‐made real‐time polymerase chain reaction using TaqMan chemistry. In parallel, the viral load (VL) in WB was measured by a commercial LightCycler EBV Quant Kit. The EBV DNA levels and dynamics of VL changes were assessed and compared between WB and PBMCs. The overall correlation between EBV DNA level in PBMCs and WB was statistically significant and high, r2=0.87 (P<0.001). However, the sensitivity of EBV detection was lower in WB (93.9%). Longitudinal analysis of EBV DNA load dynamics in PBMCs and WB indicated that EBV DNA load fluctuations were larger in WB, but the trend of decreases and increases, with minor exceptions, was similar in both sample types. The high correlation of EBV DNA levels, as well as the similar dynamics of EBV DNA changes in both sample types, make WB a good alternative to EBV DNA monitoring in PBMCs of pediatric transplant recipients. However, the subtle increase of the VL may be detected earlier in PBMCs.  相似文献   
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Zebrafish: a genetic approach in studying hematopoiesis   总被引:3,自引:0,他引:3  
The zebrafish (Danio rerio) has emerged in recent years as an exciting animal model system for studying vertebrate organ development and, in particular, the development of the hematopoietic system. The combined advantages of developmental biology and genetic screens for mutations in zebrafish have provided insights into early events in hematopoiesis and identified several genes required for normal blood development in vertebrates. As a result of the large-scale mutagenesis screens for developmental mutants, several zebrafish mutants with defects in blood development have been recovered. This review discusses how these blood mutations in zebrafish have given new perspectives on hematopoietic development.  相似文献   
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IL-28B polymorphisms are predictors of response to therapy in adults infected with hepatitis C. We do not know whether they are markers of response to therapy in children and adolescents. The aim of this study was to determine whether single-nucleotide polymorphisms (SNPs) in the IL-28B gene could influence the probability of response to therapy compared with other known baseline prognostic factors and correlate with clinical findings in pediatric patients infected with hepatitis C virus (HCV) genotypes 1 or 4. We determined three SNPs of IL-28B (rs12979860, rs12980275, and rs8099917) in 82 patients with chronic HCV infection treated with pegylated interferon alpha and ribavirin (peg-IFNα/RBV). Treatment response and clinical data were analyzed. Overall, sustained virological response (SVR) was achieved by 45 % of patients infected with difficult-to-treat HCV genotypes 1 and 4. Except for IL-28B polymorphisms, there was no association of SVR with any other clinical data. IL-28B rs12979860 CC [odds ratio (OR), 6.81; p?=?0.001] and rs8099917 TT (OR,?3.14; p?=?0.013) genotypes were associated with higher SVR rates. IL-28B rs12980275 was not significantly associated with SVR (p?=?0.058). Only the distribution between CC and CT–TT genotypes of rs12979860 significantly differentiated patients achieving early virological response (EVR) (OR,?10.0; p?=?0.011). Children with the rs12979860 CC genotype had significantly higher baseline viral load compared with CT–TT patients (p?=?0.010). In children and adolescents chronically infected with HCV genotypes 1 and 4, IL-28B rs12979860 and rs8099917 polymorphisms were the only predictors of response to peg-IFN/RBV.  相似文献   
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