In order to identify risk factors for preterm birth in singletons, data from a population-based case control survey on the island of Curacao were re-analysed. Both medical and sociodemographic variables were examined. Overall, a history of previous preterm birth and severe hypertension during the index pregnancy were indicators of adverse pregnancy outcome, in terms of preterm birth. The contribution of sociodemographic factors to the risk of preterm birth is relatively low. 相似文献
STUDY OBJECTIVE: To identify factors associated with smoking behaviour in primary school children in Hong Kong. DESIGN: A cross sectional survey in which both children and parents completed questionnaires. The main outcome measure was the smoking status of the children; and risk factors (knowledge of and attitude to smoking and demographic and socioeconomic background) were identified as predictors of ever/never smoking. SETTING AND SUBJECTS: Altogether 9598 primary school children, aged 8-13 years, and attending 27 schools from two districts in Hong Kong participated. MAIN RESULTS: The prevalence of ever-smoking was 12% (1119)-15% (760) in boys and 7% (359) in girls. It ranged from 3% in 8 year old girls to 52% in 13 year old boys. The factors associated with ever-smoking included the following: being a boy (adjusted odds ratio 2.21; 95% confidence interval 1.89, 2.59), increasing age per year (1.48; 1.40, 1.57), living in Kwai Tsing district (1.29; 1.10, 1.50), having one or more smokers at home (2.07; 1.78, 2.39), and having a father who was not working (1.41; 1.19, 1.67). Children who were ever-smokers had both seen and approved of their friends' smoking (8.79; 5.33, 14.50), had a more positive attitude towards smoking (3.35; 2.21, 5.09), and were more successful in recognising cigarette brand names and logos (1.67; 1.42, 1.96), but they lacked confidence (1.78; 1.32, 2.39). CONCLUSIONS: The influences on child smoking are multifactorial and programmes in Hong Kong are falling to curb them. The control of these risk factors must be incorporated in the smoking prevention policy of Hong Kong and supported by future enforced legislation. 相似文献
Alkylating agent-sensitive and -resistant L1210 leukemia cell lines were used to determine the tumor response to dose levels of drugs that exceeded conventional doses up to a factor of 10. Since those dose levels were lethal to the host mice, tumor response was based on the results of in vivo bioassays of spleen and/or tumor from drug-treated and control mice. When mice bearing about 10(8) drug-sensitive leukemic cells were treated with a single, conventional (approximately 10% lethal) dose of cis-diamminedichloroplatinum, L-phenylalanine mustard (melphalan), or 1,3-bis(2-chloroethyl)-1-nitrosourea, 10(1) to 10(4) tumor cells were recovered by bioassay. Treatment at doses that were 2 to 8 times the 10% lethal dose of either of those drugs resulted in no recoverable cells and survival of all bioassay recipient mice. Mice bearing advanced L1210 leukemia resistant to cis-diamminedichloroplatinum (L1210/DDPt), 1,3-bis-(2-chloroethyl)-1-nitrosourea (L1210/BCNU), cyclophosphamide (L1210/CPA), or melphalan(L1210/L-PAM) also were treated with a 10% lethal dose and greater doses of the drug to which the tumor line was resistant. Bioassay results indicated a direct correlation between dose intensity and tumor cell kill, the response being linear. Similarly, when mice with L1210/BCNU were treated with high doses of N-(2-chloroethyl)-N'-(2,6-dioxo-3-piperidinyl)-N-nitrosourea or 1,1',1'-phosphinothioylidynetrisaziridine (thioTEPA) and when mice with L1210/DDPt were treated with cyclophosphamide, an increasing, linear cell kill resulted throughout the high-dose range. Overall, these results indicate that resistance to these alkylating agents can be overcome by dose intensification and that the tumor response is linear in relation to increasing dose level. 相似文献
Invasive pulmonary aspergillosis is characterized by radiological signs allowing a correct diagnosis, including differentiation from pulmonary candidiasis, when they are associated with appropriate clinical symptoms (neutropenia and fever persisting despite broad-spectrum antibiotics). In particular the formation of a pulmonary mycetoma in a previously normal lung is one of these signs. Unlike a simple fungus ball (the saprophytic form of aspergillosis), the rounded density of invasive pulmonary aspergillosis consists of sequestrum of devitalized lung tissue owing to blood vessel invasion by Aspergillus hyphae. This morphologic phenomenon is demonstrated in the present case report and is discussed together with the other roentgenological signs of the invasive aspergillosis. 相似文献
The effect of valproic acid on the distribution of gavaged 65Zn in maternal and embryonic tissue of Sprague-Dawley rats was examined 24 h after gavaging of the drug on d 13 of pregnancy. Valproic acid treatment resulted in a significantly higher retention of 65Zn in maternal liver and lower amounts in uterus, placenta and embryos than in controls. Compared to controls, gel chromatography of maternal liver from valproic acid-treated dams showed higher 65Zn counts associated with a protein peak of molecular weight of 6,500, the approximate molecular weight of the Zn-binding protein metallothionein. These results support the idea that the teratogenicity of valproic acid is in part due to an induction of embryonic Zn deficiency secondary to a drug-induced sequestering of Zn into maternal liver that results in a decrease in maternal plasma Zn and subsequent reduction in embryonic Zn uptake. 相似文献
Polymer-associated infection is a problem of increasing importance in modern medicine. In a new approach to prevent such infections we have modified polyvinylfluoride (TEDLAR) films by graft copolymerization with N-vinylpyrrolidone to which iodine can be complexed. Grafting reaction was performed by the preirradiation technique using an electron accelerator. Grafted films were then treated in Lugol's solution for at least 24 h. Release of free iodine from the films was determined either by titration or using the agar disc diffusion test, showing an iodine release for up to 4-5 days. The antimicrobial activity of the films was tested in bacterial adhesion measurements. Bacterial and fungal cells in the range of 10(3) to 10(6) cfu/cm2 polymer were found on control samples without iodine, whereas on iodine-complexed films no viable cells could be detected at least for 5 days or even longer. Thus, microbial adhesion and growth can be inhibited by iodine-containing polymers. 相似文献
Background. We developed a method of closed-chest cardiopulmonary bypass to arrest and protect the heart with cardioplegic solution. This method was used in 54 dogs and the results were retrospectively analyzed.
Methods. Bypass cannulas were placed in the right femoral vessels. A balloon occlusion catheter was passed via the left femoral artery and positioned in the ascending aorta. A pulmonary artery vent was placed via the jugular vein. In 17 of the dogs retrograde cardioplegia was provided with a percutaneous coronary sinus catheter.
Results. Cardiopulmonary bypass time was 111 ± 27 minutes (mean ± standard deviation) and cardiac arrest time was 66 ± 21 minutes. Preoperative cardiac outputs were 2.9 ± 0.70 L/min and postoperative outputs were 2.9 ± 0.65 L/min (p = not significant). Twenty-one-French and 23F femoral arterial cannulas that allowed coaxial placement of the ascending aortic balloon catheter were tested in 3 male calves. Line pressures were higher, but not clinically limiting, with the balloon catheter placed coaxially.
Conclusions. Adequate cardiopulmonary bypass and cardioplegia can be achieved in the dog without opening the chest, facilitating less invasive cardiac operations. A human clinical trial is in progress. 相似文献
Disseminated Strongyloides stercoralis infection is a rare and severe but treatable complication of AIDS. We present a case where this infection was successfully treated and review the available literature. Cases may present many years after they have left an area endemic for Strongyloides infection, emphasizing the need for a full travel history. Symptoms are typically gastrointestinal and pulmonary, with infiltrates often seen on chest radiography. Diagnosis requires stool examination and biopsy of affected sites. Treatment with repeated courses of thiabendazole (25 mg/kg twice daily for 5 days) was successful in our case, but maintenance regimens have not yet been defined. The relative rarity of this complication of AIDS suggests that, where both infections are present, disseminated strongyloidiasis only arises either when HIV-induced immunodeficiency is profound or, possibly, when it is accompanied by impaired granulopoiesis. 相似文献