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81.
82.
We evaluated whether the presence of polycystic ovaries in adolescent girls as a cause of oligomenorrhoea and amenorrhoea would pose any protective effect against osteoporosis or low bone mineral density (BMD) compared with girls having similar menstrual dysfunction but normal ovaries. A cross-sectional observational study was done in consecutive girls, aged between 16 and 19 years, presenting to the adolescent gynaecology clinic with oligomenorrhoea or amenorrhoea. All patients underwent full hormonal profile assessment, pelvic ultrasound for ovarian morphology, bio-impedance estimation of body fat, and dual-energy X-ray absorptiometry and quantitative peripheral computed tomography scans to determine BMD in axial and appendicular skeletal sites. Polycystic ovaries were diagnosed according to ultrasound morphology. These were then compared with an age-matched eumenorrhoeic control group that had undergone the same evaluation. Of 45 patients with oligomenorrhoea or amenorrhoea, 14 (31%) were diagnosed to have polycystic ovaries, while the other 31 had normal ovaries. The control group consisted of 45 age-matched eumenorrhoeic girls. The group with normal ovaries had lower BMD at the lumbar spine and hip, as well as lower total tibial volumetric BMD, than the eumenorrhoeic controls, but there were no significant differences between the group with polycystic ovaries and eumenorrhoeic controls. We conclude that adolescents with oligomenorrhoea and amenorrhoea with normal ovaries had lower BMD than eumenorrhoeic ones, but those with polycystic ovaries had BMD values comparable to those of eumenorrhoeic controls despite their menstrual dysfunction. 相似文献
83.
84.
Smith JR Edland SD Novotny TE Hofstetter CR White MM Lindsay SP Al-Delaimy WK 《American journal of public health》2011,101(10):1876-1879
Hookah use is gaining popularity nationwide. We determined the correlates and trends for hookah use from the California Tobacco Survey. Between 2005 and 2008 hookah use increased more than 40%, and in 2008, 24.5% of young men reported ever using a hookah. Hookah use was more common among the young (18-24 years), the educated, the non-Hispanic Whites, and the cigarette smokers. Hookah use is increasing in California, especially among young adults, and in 2008 reached the highest prevalence ever reported for both genders. 相似文献
85.
Overview on SARS in Asia and the World 总被引:1,自引:0,他引:1
Severe Acute Respiratory Syndrome (SARS) is the first major novel infectious disease to hit the international community in the 21st century. It originated in southern China in November 2002, reached Hong Kong in February 2003 and spread rapidly thereafter to 29 countries/regions on five continents. At the end of the epidemic, the global cumulative total was 8098 with 774 deaths. Seven Asian countries/regions were among the top ten on the list. Mainland China and Hong Kong, SAR, accounted for 87% of all cases and 84% of all deaths. Severe acute respiratory syndrome is caused by a novel coronavirus. It has alarmed the world with its infectivity and significant morbidity and mortality, its lack of a rapid, reliable diagnostic test and lack of effective specific treatment and vaccination. The adverse impact on travel and business around the world, particularly in Asia, has been enormous.
Some lessons learnt from this epidemic included: (1) any outbreak of infectious disease can rapidly spread around the world by air travel; (2) early reporting of the outbreak to neighbouring countries/regions and the World Health Organization is essential to prevent international spread; and (3) infection control, tracing and quarantine of contacts are essential to control the epidemic. Many questions remain unanswered, including the origin and pathogenesis of the novel coronavirus, the natural history and the best specific treatment of the disease. The SARS-CoV has probably jumped from an animal host to humans. There is an urgent need to evaluate the human–animal habitat in southern China and to remove animal reservoirs if found. 相似文献
Some lessons learnt from this epidemic included: (1) any outbreak of infectious disease can rapidly spread around the world by air travel; (2) early reporting of the outbreak to neighbouring countries/regions and the World Health Organization is essential to prevent international spread; and (3) infection control, tracing and quarantine of contacts are essential to control the epidemic. Many questions remain unanswered, including the origin and pathogenesis of the novel coronavirus, the natural history and the best specific treatment of the disease. The SARS-CoV has probably jumped from an animal host to humans. There is an urgent need to evaluate the human–animal habitat in southern China and to remove animal reservoirs if found. 相似文献
86.
87.
朝藿素B和朝藿素C的结构 总被引:3,自引:0,他引:3
从朝鲜淫羊藿(Epeimedium koreanum Nadai)地上部分中分离得到二个新黄酮成分:朝藿素B(epimedokoreanin B)(Ix)和朝藿素C(epimedokoreanin C)(XV),经光谱分析证明,朝藿素B(IX)的结构为5,7,3`,4`-tetrahydroxyl-8,5`,-diprenylflavone;朝藿素c(xv)的结构为5,7,31`,7`-tetrahydroxyl-8-prenyl-2{[2`-(l-hydroxyl-l-methylethyl)-2`,3`-dihydrobenzofuran]-5`-yl}-chromone. 相似文献
88.
J Verspeelt P De Locht WK Amery 《Cephalalgia : an international journal of headache》1996,16(5):328-336
A comparative post-marketing surveillance study of the safety and efficacy of flunarizine and propranolol in the treatment of migraine was carried out. General practitioners in Belgium and the Netherlands each recruited patients for whom they would prescribe one of the study medications in the normal course of their treatment and recorded all medical events on follow-up forms for up to 8 months. A total of 1601 migraine patients were enrolled; 838 in the flunarizine cohort and 763 in the propranolol cohort. Propranolol was somewhat better than flunarizine in reducing the severity of migraine attacks, although this may have been due to a selection bias. Discontinuations of therapy due to events considered likely to be treatment-related were mostly due to the recognized side effects of the two drugs. As regards the occurrence of depressions, a total of 58 patients had depressive events, 34 in the flunarizine cohort and 24 in the propranolol cohort. Whereas migraine itself appears to be associated with an increased risk of depression, the number of previous migraine treatments was shown to be an additional risk factor for the development of depression in patients receiving flunarizine as was a history of depression. Overall, there was no appreciable difference in the risk/benefit ratio between flunarizine and propranolol. 相似文献
89.
Abstract Bronchiectasis is defined in current medical parlance as the abnormal and permanent dilatation of one or more bronchi, and in clinical practice, the condition is often characterized by features of chronic bronchial infection. Apart from occurring as a primary lung disease, bronchiectasis is a major component of two other disease entities, cystic fibrosis and diffuse panbronchiolitis. Although the three conditions have distinctly different underlying causes, they share the similarity of a predominantly neutrophilic airways inflammation, and the persistent bronchial infection by bacteria, in particular Pseudotnonas aeruginosa . Hence, new knowledge in one disease may be explored and applied in the others. 相似文献
90.
The typical CT appearance of a duodenal diverticulum is of a rounded air collection with or without fluid or contrast. An unusual case in which gas bubbles mixed with particulate matter mimicked faecal material in the large bowel is presented here. A similar appearance has been described in abnormally dilated small bowel, usually associated with obstruction, and is probably due to stasis of undigested food. 相似文献