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51.

Background  

Relatively little is known about the significance of normal variation in objectively assessed sleep duration and its regularity in children's psychological well-being.  相似文献   
52.
Retinoblastoma family proteins pRb, p107 and p130 are differentially expressed in the rat testis. They function in specific cell types during testicular development and spermatogenesis, participating in the control of proliferation, differentiation, and survival. Their expression levels and phosphorylation status are modulated during germ cell cycle progression and apoptosis. Hyperphosphorylated states and elevated levels of p107 are correlated with cell cycle progression, whereas hypophosphorylated states and reduced levels are associated with suppression of proliferation and apoptosis in germ cells and Leydig cells. These proteins may also serve as markers of cell cycle status of germ cells during spermatogenesis.  相似文献   
53.
Transforming growth factor-betas (TGF-beta) regulate a wide variety of cellular functions in normal development and are involved in both tissue homeostasis and disease pathogenesis. The regulation of the TGF-beta family of growth factors is unique because they are targeted to the extracellular matrix in a biologically inactive form. The release from pericellular matrices and the activation of TGF-beta are important mechanisms in several pathophysiologic conditions. Reactive oxygen species (ROS) can activate TGF-beta either directly or indirectly via the activation of proteases. In addition, TGF-beta itself induces ROS production as part of its signal-transduction pathway. The lung is a unique organ, because its structures act as boundaries between gaseous and aqueous phases, allowing the utilization of inhaled oxygen. However, this renders pulmonary tissues vulnerable to the toxic effects of inhaled air. The oxidant pathways are especially relevant in the lung, where TGF-beta is known to have a role in tissue repair and connective tissue turnover. In pulmonary fibrosis, TGF-beta activation is considered as a hallmark of disease progression. More recently, the oxidative effects of cigarette smoking have been found to activate TGF-beta in chronic obstructive pulmonary disease (COPD), a disease consisting of emphysema, airway fibrosis, and focal lung fibrosis.  相似文献   
54.
Current perspectives on HER2 testing: a review of national testing guidelines.   总被引:14,自引:0,他引:14  
Knowledge of HER2 status is a prerequisite when considering a patient's eligibility for Herceptin (trastuzumab) therapy. Accurate assessment of HER2 status is essential to ensure that all patients who may benefit from Herceptin are correctly identified. There are several assays available to determine HER2 status: the most common in routine clinical practice are immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Various factors can affect the results achieved with these assays, including the assay antibody/probe, the methodology and the experience of personnel. Many countries have implemented national testing guidelines in an attempt to standardize testing procedures and make results more accurate. These guidelines vary in the level of detail and the number of recommendations. This review looks at areas of consensus between the different national testing guidelines and highlights where errors may arise during the testing procedure. The key point underlined by this review is that whatever method is used to test for HER2 status, the technology must be validated first, and there must be regular internal and external quality control and quality assurance procedures.  相似文献   
55.
Sleep problems in young children are among the most common concerns reported to paediatricians. Sleep is thought to have important regulatory functions, and sleep difficulties in early childhood are linked to several psychosocial and physiological problems. Moreover, several prenatal factors have been found to influence infants’ sleep. Among them, most of the studies have been focused on maternal prenatal depression and/or anxiety as potential risk factors for sleep problems in childhood, whereas other relevant psychological factors during pregnancy have not received as much attention. Therefore, we aimed to examine the effect of several psychiatric maternal risk factors during pregnancy (i.e. symptoms of anxiety, depression, insomnia, alcohol use, seasonality, attention deficit and hyperactivity disorder and/or stressful life events) on the onset of some sleep problems related to sleep quality and sleep practices in 3‐month‐old infants. We examined 1,221 cases from a population‐based birth cohort, with subjective measures during pregnancy in mothers, and at 3 months after birth in the infants. The findings showed that all the maternal risk factors during pregnancy, except for symptoms of alcoholism and sleepiness, were related to sleep difficulties in infants. Interestingly, attention deficit and hyperactivity disorder symptomatology in mothers during pregnancy was the only variable that predicted more than two sleeping difficulties (i.e. long sleep‐onset latency, co‐sleeping with parents and irregular sleeping routines) at 3 months old. Our results highlight the relevance of maternal risk factors during pregnancy, and not only prenatal depression and/or anxiety, as variables to be considered when examining sleep difficulties in infants.  相似文献   
56.

Objective

Aurora-A is a potential oncogene and therapeutic target in ovarian carcinoma. It is involved in mitotic events and overexpression leads to centrosome amplification and chromosomal instability. The objective of this study was to evaluate the clinical significance of Aurora-A and DNA ploidy in serous ovarian carcinoma.

Methods

Serous ovarian carcinomas were analysed for Aurora-A protein by immunohistochemistry (n = 592), Aurora-A copy number by CISH (n = 169), Aurora-A mRNA by real-time PCR (n = 158) and DNA ploidy by flowcytometry (n = 440).

Results

Overexpression of Aurora-A was found in 27% of the tumors, cytoplasmic overexpression in 11% and nuclear in 17%. The cytoplasmic and nuclear overexpression were nearly mutually exclusive. Both cytoplasmic and nuclear overexpression were associated with shorter survival, high grade, high proliferation index and aberrant p53. Interestingly, only cytoplasmic expression was associated with aneuploidy and expression of phosphorylated Aurora-A. DNA ploidy was associated with poor patient outcome as well as aggressive clinicopathological parameters. In multivariate analysis, Aurora-A overexpression appeared as an independent prognostic factor for disease-free survival, together with grade, stage and ploidy.

Conclusions

Aurora-A protein expression is strongly linked with poor patient outcome and aggressive disease characteristics, which makes Aurora-A a promising biomarker and a potential therapeutic target in ovarian carcinoma. Cytoplasmic and nuclear Aurora-A protein may have different functions. DNA aneuploidy is a strong predictor of poor prognosis in serous ovarian carcinoma.  相似文献   
57.
Serum low-density lipoprotein (LDL) particle composition varies according to lifestyle and age. To analyze its long-term tracking, we studied LDL particle size consecutively in 100 children at the ages of 7, 9 and 11 years using a high-resolution 3% polyacrylamide gel tube, electrophoresis method, searching also for long-term determinants of the particle size. The mean LDL particle sizes at 7 and 9 years, and at 7 and 11 years correlated directly (r = 0.72 and 0.39, respectively). The probability that children would remain in the same LDL particle size tertile between 7 and 11 years of age was 48% (p = 0.008). Longitudinally, total, high-density lipoprotein (HDL) and LDL cholesterol concentrations and body mass index (BMI) associated directly with mean LDL particle size, and triglyceride concentration and triglyceride/HDL cholesterol ratio correlated inversely. A shift from pre-puberty to puberty was associated with an increase in LDL particle size. Sex, serum insulin concentration, or energy nutrient intakes did not associate with LDL particle size. In conclusion, although mean LDL particle size tracks in 7- to 11-year-old healthy children, changes in serum triglycerides, HDL, LDL, and total cholesterol concentration, BMI, and pubertal status all modify LDL particle size.  相似文献   
58.
OBJECTIVE: To evaluate the longitudinal impact of dietary counseling on children's nutrient intake. DESIGN: A prospective, randomized, clinical trial. PARTICIPANTS: Children were recruited to the study between December 1, 1989, and May 30, 1992. At the age of 7 months, children were randomized to the intervention group (n = 540) or the control group (n = 522) and were followed up until the age of 10 years.Intervention Families in the intervention group have, since randomization, received regularly individualized counseling about how to modify the quality and quantity of fat in the child's diet, the goal being an unsaturated-saturated fat ratio of 2:1. MAIN OUTCOME MEASURES: Nutrient intakes between the ages of 4 and 10 years based on annual 4-day food records. RESULTS: The fat intake of the intervention children was constantly around 30% of the calorie (energy) intake, while that of the control children was 2 to 3 calorie percentage units higher (P<.001). The intervention children received 2 to 3 calorie percentage units less saturated fats and 0.5 to 1.0 calorie percentage unit more polyunsaturated fats than the control children (P<.001 for both). However, neither group reached the 2:1 goal set for the unsaturated-saturated fatty acid ratio. The vitamin and mineral intakes of the intervention and control children closely resembled each other despite the marked differences in fat intake. CONCLUSION: Individualized, biannually given, fat intake-focused dietary counseling that began at the child's age of 8 months continued to influence favorably the diet of 4- to 10-year-old intervention children without disadvantageous dietary effects, but the 2:1 goal for unsaturated-saturated fat ratio was not reached.  相似文献   
59.
60.
In previous studies, we have reported endoscopic and histological alterations locally on the gastrointestinal (GI) tract associated with a gastrointestinal type of cow's milk allergy. In this study, we sought to further characterize endoscopic, and immunological findings in these children. We also hypothesized that the same type of immune responses might also be found in children with unexplained and recurrent abdominal pains. We did a gastroduodenoscopy for persistent GI symptoms, examined the mucosal histology of the small intestine and measured the antibodies to whole cow's milk and its fractions with an enzyme‐linked immunosorbent assay (ELISA) in a consecutive series of 22 subjects with untreated and 14 with treated cow's milk allergy (CMA) and 44 with recurrent abdominal pains (RAP). The immunological findings of the study subjects were compared with 54 controls. Lymphonodular hyperplasia (LNH) of the duodenum was the main endoscopic finding in 11 subjects (50%) with untreated and 5 (36%) with treated CMA. It was also found in 6 of 44 subjects with RAP. Compared with the controls, the patients with CMA showed significantly higher levels of IgA class antibodies to whole milk (p = 0.003) and βLG (p < 0.0001). Of the IgG class antibodies to βLG (p = 0.032), BSA (p < 0.0001) and αCAS (p < 0.0001) were significantly higher. The patients with LNH of the duodenal bulb as the main endoscopic finding showed significantly higher values of IgG class antibodies to βLG (p = 0.01) and αCAS (p = 0.005). Interestingly, the patients examined for RAP showed a similar increment in the pattern of whole milk and specific milk protein antibodies as the CMA children. In conclusion this study showed that gastrointestinal CMA beyond infancy is significantly associated with high levels of IgG and IgA class antibodies to milk and its fractions. As high levels of these antibodies and LNH of the duodenal bulb were also found in subjects with RAP, the study further suggests that gastrointestinal CMA might be one major reason for RAP.  相似文献   
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