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41.

Background  

Children in urban public housing are at high risk for asthma, given elevated environmental and social exposures and suboptimal medical care. For a multifactorial disease like asthma, design of intervention studies can be influenced by the relative prevalence of key risk factors. To better understand risk factors for asthma morbidity in the context of an environmental intervention study, we conducted a detailed baseline evaluation of 78 children (aged 4–17 years) from three public housing developments in Boston.  相似文献   
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An orthotopic, isogenic rat model was used to determine the potential of chemoembolization (CHE) for reducing the tumor cell load of a diffusely metastatic liver. Seven days after injecting CC531-lac-Z cells intraportally to male WAG/Rij rats, tumor positive animals were treated by injection into the hepatic artery with solvent (n=17), degradable starch microspheres (DSM, 30 mg/kg; n=16), DSM plus 5-fluorouracil (5-FU, dosages: 90, 60, and 40 mg/kg) or DSM plus gemcitabine (Gem, dosages: 100, 80, 50, and 10 mg/kg). After 3 more weeks the experiment was terminated, the livers were weighted and the number of CC531-lac-Z cells per liver was determined. Injection of DSM reduced the tumor cell load by 21% (T/C%=79), the combination with 5-FU caused a stimulation of growth at 40 mg/kg (T/C%=291; n=10), but effected dose-dependent reductions in tumor cell number at 60 mg/kg (T/C%=86; n=16), and 90 mg/kg (T/C=19; n=17). None of these effects was significantly different from controls. The combination of DSM plus Gem was toxic at the highest dose (100 mg/kg), but well tolerated and highly effective at 80 mg/kg (T/C%= 16; n=12), 50 mg/kg (T/C%=9; n=12), and 10 mg/kg (T/C%=26; n=14). These results were significantly different from controls (p<0.05), respectively. In summary, the comparison of CHE with 5-FU or Gem shows that the efficacy of Gem in reducing the hepatic tumor cell load was significantly higher and its therapeutic ratio was greater than that of 5-FU.  相似文献   
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Treatment of achalasia: recent advances in surgery   总被引:14,自引:0,他引:14  
Achalasia is an uncommon motility disorder of the esophagus with an uncertain etiology. Considerable debate exists regarding the most effective treatment for long-term relief of symptoms. For decades, pneumatic dilatation has been the primary treatment option, and surgery was reserved for patients who required repeated dilations or for those who were not willing to undergo the risk of perforation associated with dilatation. Recently botulinum toxin injection of the lower esophageal sphincter has been shown to provide substantial short-term relief from dysphagia; however, its effect only lasts for a short period of time. Recently, minimally invasive surgical techniques have been developed to perform a Heller myotomy effectively with an antireflux procedure. This has become a primary treatment option for many patients. We present a review of the outcome of different therapeutic options of achalasia with a special focus on laparoscopic procedures.  相似文献   
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Undislozierte Densbasisfrakturen k?nnen nativradiologisch ohne Berücksichtigung des zugrundeliegenden Unfallmechanismus eine Stabilit?t vort?uschen, die bei konservativer Therapie zu sekund?ren Dislokationen führen k?nnen. Dies wird vor allem bei der Klassifikation der Dens Frakturen nach Anderson und D'Alonzo leicht übersehen. Anhand einer Kasuistik wird diese Problematik aufgezeigt, der operative Anspruch einer vermeidbaren, risikoreichen transoralen Korrekturosteotomie dargelegt und auf eine aussagekr?ftigere Klassifikation der Densfrakturen verwiesen.  相似文献   
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Prophylactic treatment of postmenopausal osteoporosis with oestrogen and calcium, often in combination, disregards the likelihood that an excess of each agent may increase magnesium requirements and decrease serum Mg levels. Relative or absolute Mg deficiency, which is likely in the Occident where the Mg intake is commonly marginal, can militate against optimal therapeutic bone response, Mg being important for normal bone structure, and can increase the risk of adverse effects. Although oestrogen has cardiovascular protective effects (expressed by the lower incidence of heart disease in premenopausal women than in men, and also in postmenopausal women given low dosage oestrogen replacement treatment), high dosage oestrogen oral contraceptives have caused increased intravascular blood clotting with resultant thromboembolic cardio- and cerebrovascular accidents. This might be contributed to by the oestrogen-mediated shift of circulating Mg to soft and hard tissues, which in persons with marginal Mg intakes may lead to suboptimal serum levels. If the commonly recommended dietary Ca/Mg ratio of 2/1 is exceeded (and it can reach as much as 4/1 in countries with low to marginal Mg intakes), relative or absolute Mg deficiency may result, and this may increase the risk of intravascular coagulation, since blood clotting is enhanced by high Ca/Mg ratios. Mechanisms by which Ca activates the various steps in blood coagulation that are also stimulated by oestrogen are considered here, as are the multifaceted roles of Mg that favourably affect blood coagulation and fibrinolysis, through its activities in lipoprotein and prostanoid metabolism.  相似文献   
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